A transmission device includes a first element having rolling surfaces of revolution on a first axis, a second element having surfaces of revolution on a second axis intersecting the first axis at an acute angle equal to or slightly larger than an apex half-angle of each of a pair of generally conical surfaces on one of the elements. The rolling surfaces of both elements are symmetrically disposed axially on each side of the point of intersection. The second element is mounted such that its axis may perform conical movement about the axis of the other element. The second element may be allowed a degree of freedom to pivot about the point of intersection of the axes and in the plane containing the axes, so that during operation of the device, a gyroscopic couple of the body causes it to pivot so that the cone surfaces and their respective rolling surfaces come into rolling engagement at points one each side of the point of intersection of the axes. Alternatively, the same gyroscopic couple may be used to counterbalance forces by which the rolling surfaces are held in frictional contact by mechanical means where no pivotal freedom is provided. The annular rolling surfaces may be axially movable apart to alter the transmission ratio. Drive input and output means are coupled to either the rotation of the body about its axis, rotation of the second element conically about the point on the first axis and circumferentially of the longitudinal axis, or the rotation of the rolling surfaces about their axes. Two or more rotating units may be coupled together in such a way that the resultant or composite moment along the axis of the transmission is zero.
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1. A transmission device comprising a frame, drive input means, drive output means, and means interconnecting said input and output means including a first element having a first axis fixed relative to the frame, and a second element rotatable about a second axis intersecting said first axis at a point thereon, said second element being driven conically about said point on the first axis and circumferentially of said first axis, said first element having a pair of rolling surfaces disposed about said first axis one each side of the plane passing through the point of intersection of said axes and perpendicular to said first axis, said second element having a pair of rolling surfaces disposed about said second axis, one each side of the plane passing through the point of intersection of said axes and perpendicular to said second axis, rolling surfaces of one of said elements being the surfaces of cones having an apex half-angle substantially equal to the angle of intersection of said first and second axes, a gyroscopic action of said second element producing a couple bringing holding the respective rolling surfaces on said first and second elements into in rolling engagement at two points located one each side of the plane passing through the point of intersection of said axes and perpendicular to said first axis.
20. A transmission comprising a frame, drive input means, drive output means, and means interconnecting said input and output, said interconnecting means comprising a plurality of transmission devices each including a first element having a first axis fixed relative to the frame, and a second element rotatable about a second axis intersecting said first axis at a point thereon, said second element being driven conically about said point on the first axis and circumferentially of said first axis, said first element having a pair of rolling surfaces disposed about said first axis one on each side of the plane passing through the point of intersection of said axes and perpendicular to said first axis, said second element having a pair of rolling surfaces disposed about said second axis, one on each side of the plane passing through the point of intersection of said axes and perpendicular to said second axis, the rolling surfaces of one of said elements being the surfaces of cones having an apex half-angle substantially equal to the angle of intersection of said first and second axes, a gyroscopic action of said second element producing a couple bringing respective rolling surfaces on said first and second elements into rolling engagement at two points located one on each side of the plane passing through the point of intersection of said axes and perpendicular to said first axis, and the transmission devices being coupled so that the resultant of the gyroscopic couples to which the second elements of the transmission devices are subjected is substantially zero.
23. A transmission device comprising: a frame, drive input means, drive output means, and means interconnecting said input and output means including a first element having a first axis fixed relative to the frame, and a second element having a second axis intersecting said first axis at a point thereon, and support means to engage said second element on said second axis at opposite sides of said point, said support means being rotatable on said first axis under a torque couple driving said second element being driven conically about said point on said first axis and circumferentially of said first axis, said first element having a pair of rolling surfaces disposed about said first axis, one on each side of a first plane passing through said point of axes intersection and perpendicular to said first axis, said second element having a pair of rolling surfaces disposed about said second axis, one on each side of a second plane passing through said point of axes intersection and perpendicular to said second axis, the respective rolling surfaces on said first and second elements being in rolling frictional engagement at two points in a third plane containing said first and second axes and located one on each side of said first plane, and the rolling surfaces of one of said elements being the surfaces of cones having an apex half-angle related to the angle of intersection between said first and second axes in a manner to enable the spacing between said respective two points of rolling frictional engagement and said point of axis intersection to be adjusted along the length of said rolling surfaces for any given angle of said first and second axes intersection, and means for forcing said respective rolling surfaces of said first and second elements into rolling friction engagement with each other at said two points.
69. In a transmission device having a frame, drive input means and drive output means, means interconnecting said input and output means comprising:
a first element on a first axis fixed in the frame and having rolling surfaces of revolution about said first axis, one such rolling surface on each side of a first plane perpendicular to said first axis at a point of axes intersection; a second element having rolling surfaces of revolution about a second axis intersecting said first axis at said point of axes intersection and at an angle of axes intersection, the rolling surfaces of said second element being disposed one one each side of a second plane passing through said point of axes intersection and perpendicular to said second axis; means to support said second element symmetrically on opposite sides of said point of axes intersection from the frame to establish fix said angle of intersection and so that the rolling surfaces on said elements may be in rolling friction engagement at two points of contact in a third plane containing said first and second axes, said points of contact being located symmetrically with respect to said point of axes intersection; the rolling surfaces of both said elements being symmetrical with respect to said point of axes intersection and the rolling surfaces of at least one of said elements being defined by generatrices inclined oppositely with respect to the axis of revolution thereof, the rate of inclination of said generatrices being related to said angle of intersection so as to effect a ratio of rolling surface radii at said points of contact dependent on the spacing of said points of contact from said point of axes intersection; means for forcing said respective rolling surfaces on said first and second elements into rolling frictional engagement with each other at said two points; and means to adjust simultaneously the spacing of said points of contact from said point of axes intersection thereby to vary the speed ratio of the drive input and drive output means.
41. In a transmission device having a frame, drive input means, and drive output means, means interconnecting said input and output means comprising:
a first element on a first axis fixed in the frame and having rolling surfaces of revolution about said first axis, one such rolling surface on each side of a first plane perpendicular to said first axis at a point of axes intersection; a second element on a second axis intersecting said first axis at said point of axes intersection and having concentric journal and rolling surfaces of revolution about said second axis, the rolling surfaces of said second element being disposed one on each side of a second plane passing through said point of axes intersection and perpendicular to said second axis said journal surfaces also being disposed one on each side of said second plane; support means rotatable on said first axis and journalled with said journal surfaces to support said second element in a manner to positively establish the angle of intersection between said first and second axes and for movement of said second element and said second axis in a biconical path circumferentially of said first axis, the apex of said biconical path being having a central apex coincident with said point of axes intersection and diverging oppositely from said central apex at a rate of divergence established by the support of said second element from said support means; the respective rolling surfaces on said first and second elements being symmetrical with respect to said point of axes intersection and being in rolling frictional engagement at two points of contact in a third plane containing said first and second axes and located one on each side of said first plane; the rolling surfaces of at least one of said elements being defined by generatrices inclined oppositely with respect to the axis of revolution thereof, thereby to provide in the respective rolling surfaces of said first and second elements a variable ratio of rolling surface radii at said points of contact for variation in the spacing of said points of contact from said first plane; and means for forcing said respective rolling surfaces on said first and second elements into rolling friction engagement with each other at said two points.
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CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of U.S. application Ser. No. 598,625 filed on July 24, 1975 by the present inventor, now abandoned.
This invention relates to transmission devices. More particularly the invention relates to transmission devices of the type including a frame, a first element having a first axis fixed relative to the frame, and a second element rotatable about a second axis intersecting the first axis, the second axis being arranged for nutation about the first axis with the apex of the cone of nutation being the point of axes intersection. The first element has rolling surfaces of revolution disposed about the first axis and the second element has rolling surfaces of revolution disposed around the second axis. Provision is made for bringing the rolling surfaces of revolution around the axes into rolling engagement and drive input or output means is connected to at least one of the first and second elements.
In U.S. Pat. No. 3,955,432 issued May 11, 1976 to the present inventor, there is disclosed a transmission having a first element defining a pair of rolling surfaces of revolution about a first axis, a second element having a pair of rolling surfaces of revolution on a second axis intersecting the first axis and including a mechanical system for urging the rolling surfaces of the second element against those of the first element, which system is gyroscopic in origin. Specifically, gyroscopic means are associated with the second element to develop a gyroscopic couple which acts to retain the rolling surfaces of the second element against the rolling surfaces of the first element at two points located one on each side of a plane perpendicular to the first axis at the point of intersection thereof with the second axis. The gyroscopic forces thus developed are a combined function of the moment of inertia of the second element with respect to the second axis, the angle at which the first and second axes intersect, the rotational velocities of the second element around the second axis and nutational velocity of the second axis around the first axis. In this transmission, the gyroscopic force couple operates to both rock the second element around the point of axes intersection and maintain both rolling surfaces of the second element against both such surfaces of the first element in rolling friction contact.
To vary the ratio of input and output speeds of the transmission disclosed in this patent, provision is made to modify the angle of inclination of the second axis with respect to the first axis. As a result, the ratio of the radii of circles described by the points of rolling surface contact between the first and second elements, respectively, will be modified. Such a transmission is particularly well suited for the transmission of large forces due to the development of normal contact pressure by the gyroscopic forces while avoiding excessive axial forces on the transmission gear shafts as well as radial forces on the bearing supporting the second element.
Although the transmission disclosed in U.S. Pat. No. 3,955,432 possesses many desirable features, it is subject to certain drawbacks particularly when it necessary to vary the input and output speeds of the transmission over large ranges. This drawback is due primarily to the necessity for variation of the angle of inclination of the second axis with respect to the first axis. In other words, to obtain the rotary motion of the second element about its own axis as well as nutational movement of the second axis about the first axis, it is necessary to employ relatively complex mechanical coupling connections to the second element such as homokinetic joints, etc. In addition, the transmission of this patent is subject to drawbacks when the rotational velocity of the second axis about the first axis varies through transient ranges. During these transient ranges, the gyroscopic couple assumes values different from the nominal value in normal operation. The result is that the normal force creating the contact pressure deviates from its optimum value in such transient ranges. Although this drawback is of minor importance when the transmission operates continuously under normal conditions, it becomes a more serious problem when the transient ranges are more frequently incurred.
In U.S. Pat. Nos. 2,319,319, 2,405,957 and 2,535,409 transmission devices are described which comprise a plurality of second elements which are conical and convex in form and arranged in satellite manner about a first axis. The rolling surfaces of revolution formed on these conical elements are held in contact with an annular, toric, concave part at points of contact identical in number to the number of conical satellite elements. Each of these conical satellites is supported either at its two extremities by bearings located inside support plates having as their axis the first axis, as in U.S. Pat. No. 2,319,319, or at its small conical extremity by bearings located inside a support plate having as its axis the first axis, as in U.S. Pat. Nos. 2,405,957 and 2,535,409.
The pressure at the point of contact between the various conical satellites and the toric ring with which they cooperate is obtained by the combined effect of the centrifugal force acting on the conical satellites when the support plate or plates rotate and by a possible additional force applied radially to each of the satellites, such as springs, for example. In the transmission devices described in U.S. Pat. Nos. 2,319,319 and 2,405,957, the bearings are rotatably mounted inside the support plate so as to permit the satellite a certain degree of liberty in a radial plane. This arrangement allows the conical satellite to abut on the toric ring under the action of centrifugal force. In the transmission described in U.S. Pat. No. 2,535,409, the bearing in the support plate is blocked by means of a wedge system of such dimensions that it presses the conical satellites against the toric ring with a contact force which allows the transmission device to function in the absence of centrifugal force.
The concave toric ring is movable along its longitudinal axis, i.e. along the first axis, so as to modify the ratio of the radius R1 of the circles described by the points of contact on the reaction surfaces of the satellites to the constant radius R2 of the circles described by the points of contact of the reaction surface of the toric ring.
The rotation of the satellite support plate or plates draws each of these satellites in a movement around the surface of a cone with an apex angle a and having as its axis the first axis. Each of these satellites abuts on the rolling surface of the ring at a single point of contact. As the ring is immobile, when rotating about the axis of the ring (the first axis), the satellites react by starting to turn on themselves about their own axis (the second axis). The combination of the driving speed of the conical movement of each of these satellites and its rotational speed about its own axis is transmitted, by a planetary geartrain, to a drive transmission shaft coaxial with the first axis.
The transmission devices of these last mentioned U.S. patents have the following features:
(a) The force perpendicular to the rolling surfaces and exerted at the point of contact is minimum when the R1 :R2 ratio is high (point of contact at the large base of the cone, large contact surface), and is maximum when the R1 :R2 ratio is low (point of contact at the small base of the cone, small contact surface). This results in considerable variations in the specific contact pressure.
(b) The axial and radial reaction forces balancing out the contact pressure are accommodated by the bearing blocks supporting the conical satellites. These forces are directed in one direction or the other, depending on whether the points of contact are located on one side or the other of the satellite center of gravity. These forces are generally considerable, as they are of the same order of magnitude as the perpendicular contact force. The result is that the bearing blocks supporting the satellites must be designed and dimensioned so as to accommodate substantial forces during operation. Accordingly, it is difficult to exert very large forces at the point of contact.
(c) In addition to the centrifugal force which helps to keep the conical satellite lying in frictional rolling contact with the toric ring, a gyroscopic couple is also generated. In the case of these known transmission devices, this couple produces an undesirable effect, as its influence reduces the pressure at the point of contact and increases the radial force to be accommodated by the bearing blocks supporting the conical satellites.
The aim of the invention is to eliminate or at least substantially reduce the drawbacks mentioned hereinbefore while retaining the advantages of transmission devices of these general types. More particularly, the invention concerns a transmission of these general types comprising a new mechanism for varying the speed ratio of the transmission.
According to the invention, there is provided a transmission device having a frame, a first element having a first axis fixed relative to the frame, and a second element rotatable about a second axis intersecting the first axis at a point thereon, the second axis being driven conically about the point on the first axis and circumferentially of the first axis. The first element has a pair of rolling surfaces of revolution disposed about the first axis, one on each side of a plane passing through the point of intersection of the axes and perpendicular to the first axis. The second element has a pair of rolling surfaces of revolution disposed about the second axis, one on each side of another plane passing through the point of intersection of the axes and perpendicular to the second axis. The rolling surfaces of revolution of one of the elements are essentially the surfaces of cones having an apex half-angle substantially equal to or less than the angle of intersection of the first and second axes. Drive input or output means is connected to at least one of said first and second elements.
The transmission of the present invention comprises also a mechanical system for creating the pressure contact between the rolling surfaces. This mechanical system may be realized in different ways. Preferentially this mechanical system comprises gyroscopic means or is associated with gyroscopic means. In fact, a complementary aim of the present invention is the advantageous deployment of the inertia phenomenon which occur in a body moving about a fixed point, the classic example of such phenomenon being identified in the operation of a gyroscope. The second element in the transmission of the invention is a body having a rotational movement about its axis (the second axis), such axis in turn having a conical rotation movement about the first axis (normally the general transmission axis), with the apex of such conical movement on the point of intersection of the two axes. This cone of movement is generally termed the cone of nutation.
The elemental inertia forces generated in the mass of the second element may be reduced--using the general laws of mechanics--to a couple and an applied force at the point of intersection of the axes.
(a) The applied force:
When the center of gravity of the second element substantially coincides with the point of intersection of the axes, the applied force is substantially zero. In the opposite case, the applied force is a turning force located in the plane perpendicular to the general transmission axis (the first axis). According to a preferred feature of the present invention therefore, the center of gravity of the second element is at or adjacent to the point of intersection of the axes so as to limit the intensity of the applied force.
It should be noted, on the other hand, that in the case of the transmission devices described in the above-mentioned U.S. patents, the center of gravity of the second element is very remote from the point of intersection of the axes, so as to create the greatest possible applied force. In fact, in the known transmission devices, it is chiefly because of this applied force that the second element is kept in rolling frictional contact with the first element.
(b) The couple:
The gyroscopic couple may be mathematically represented by a vector, the direction of which is perpendicular to the plane containing the first and second axes. Accordingly, this couple has the effect of pivoting the second element about an axis perpendicular to the plane containing the first and second axes.
In accordance with another desired feature of the invention, the second element is a substantially solid body rotating about the second axis having a transverse plane of symmetry perpendicular to the second axis at the point of intersection of the axes.
By applying the classic laws of the mechanics of solids, it is possible to calculate the moment of this couple (i.e. the modulus of the vector) in the case of a rotating solid body. This moment is given by the following formula:
CI=(I1 -I3)Wa2 sin a cos a-I3 Wa(Wa-Wb) sin a
In this formula:
I1 and I3 designate the moments of inertia of the second element relative to the second axis and relative to an axis passing through the point of intersection of the axes and perpendicular to the second axis;
a designates the angle of inclination of the second axis relative to the first axis;
Wa designates the angular velocity of the second element about the first axis; and
Wb designates the angular velocity of the second element about the second axis in a frame of reference which is fixed relative to the assembly.
The notation Wb*, though not used in the formula, but which will also be used below, designates the angular velocity of the second element about the second axis in a frame of reference which is linked to the rotating plane containing the first and second axes. Thus, in terms of Wb* and Wb, Wb*=Wb-Wa.
Similarly, the notation W, where used hereinafter, designates the velocity of the first element about the first axis.
The formula gives the intensity of the moment of the gyroscopic couple resulting from the total inertia forces. The formula is written in two parts so as to show, in the first part, the contribution made by inertia effects which may be termed "centrifugal". In fact, when Wa=Wb, the second part of the expression disappears, leaving only the first part, independent of the value of the angular velocity of the second element about its rotational axis (the second axis).
It should be generally noted that, in transmission devices according to the invention, Wa≠Wb (Wb*≠0).
The expression for the moment of the gyroscopic couple is an algebraic total. Consequently and depending on the value of each of the parameters, this couple may either act in a direction to press the second element against the first, or, on the other hand, act in a direction tending to oppose movement of the second element against the first.
In other words, the different parameters, such as the shape of the second element affecting (I1, I3), the angular velocity (Wa, Wb), and the angle of conical movement a for each embodiment, may be proportioned so as to obtain a couple with an intensity equal to that needed to hold the second element in place against the first and variable in proportion to the power to be transmitted by the transmission device.
Calculation of the structural and kinematic parameters of the aforementioned second element to determine the gyroscopic properties thereof and in particular, the direction and intensity of the force couple developed by movement of the second element, lies within the capability of one skilled in the art relating to the gyroscopic devices by direct application of the aforementioned formula. In accordance with one of the basic principles underlying the present invention, therefore, the direction and intensity of the gyroscopic force couple are selected either to hold directly the force transmitting rolling surfaces of the respective first and second elements one against the other or to counter-balance the forces under which such surfaces are held one against the other by mechanical means incorporated in certain embodiments of the invention.
It is contemplated that many embodiments of the present invention are possible and may differ in that the direction of the gyroscopic couple is employed to retain the respective rolling surfaces of the first and second element one against the other or in that the same couple is deployed to counter-balance the forces by which said rolling surfaces are retained against each other. In the preferred embodiments of the present invention, however, one of the elements is of generally biconical configuration to establish generally conical surfaces of revolution symmetrical about a transverse axis passing through the axes of intersection of the first and second elements, each such conical surface having an apex half-angle no greater than the angle at which the axes of the first and second elements intersect.
It is not essential for the second element to be located inside the first element or that the second element be convex and the first element concave in the transverse plane. A transmission device is contemplated according to the invention wherein the first element is located inside the second element, i.e. a transmission device wherein the rolling surfaces of the first element are generally convex in shape and those of the second element are generally concave in shape in the transverse plane. Similarly, a transmission device according to the invention might be such that, in a meridian plane (i.e. a radial plane including the first axis), the general forms of the rolling surfaces would be concave or convex rather than linear. In other words, a surface which may appear generally conical in illustrative drawings is not restricted to the surface generated solely by revolution of a straight line, but rather is inclusive of surfaces which may be slightly convex or concave, such as where the generatrix of the surface is a curve. Such convex or concave surfaces may be employed so long as they permit the transmission ratio to be varied without changing the angle of inclination of the axis of the second element with respect to the axis of the first. When used in this specification and claims, therefore, a reference to cones or to conical surfaces shall be construed as embracing not only cones whose surface is linear but convex or concave subject to the foregoing limitation. In the case of such convex or concave surfaces, the apex half-angle of the cone shall be treated as the average value of the angle of the tangents to the generatrix of each said surface with respect to the axis of revolution of the surface.
The choice of the radii of curvature of the reaction surfaces in the transverse and meridian planes, all other factors being equal, permits ranges of variation in output velocity which are different for a given breadth of variation of the ratio (R1/R2), different laws of variation of the power transmitted as a function of the output velocity, and different load transmissions. Thus, it is possible to adapt a transmission device according to the invention to the desired operating conditions.
Although it is obviously necessary for the transmission device to comprise at least two drive transmission shafts, one for input and one for output, it is not essential that these drive transmission shafts be rotatably connnected to the first and second elements respectively. In fact, it is perfectly possible for one of the drive transmission shafts to be linked to the rotational movement of angular velocity Wb* of the second element about its axis (i.e. the second axis) and for the other drive transmission shaft to be linked to the rotation, of angular velocity Wa, of the second element about the first axis (i.e. the second axis about the first axis).
The first element may be either fixed, or rotatable about the first axis. If it is necessary for the second element to be rotatable, with a velocity Wa, about the first axis, it is still not essential for the first element to be rotatable about this axis. By contrast, it shold be noted that where the first element is rotatable about the first axis, it is possible to link it rotatably to a drive transmission shaft and to block the rotation of the drive transmission shaft linked to the movement of rotation, of angular velocity Wb*, of the second element about its axis (i.e. the second axis).
The first and second elements could be linked in other different ways to drive transmission shafts. It should be specified here that the expression "rotatably linked," as used in the present description and in the claims, refers to identical angular velocities or angular velocities in a given constant ratio or in a given variable ratio, while the expression "mounted for rotation with" refers to identical angular velocities.
According to a further subsidiary feature of the invention, the drive transmission shaft (the first shaft) may be rotatably linked to the second element by providing the first drive transmission shaft with a single truncated cylindrical part having as its axis the said first axis, and having at each end a respective support plate, the second element being provided with a pair of coaxial half shafts fixed relative thereto and rotatably supported in bearings on the respective support plates, the axis of the half shafts being the said second axis. Preferably in this embodiment, the bearings in which the two half-shafts are supported are mounted inside sleeves which are prismatic in their external shape. The sleeves are mounted in said support plates with play in the plane containing the first and second axes, and with substantially no play in the direction perpendicular to this plane, whereby the second element is mounted on the support plates with a sufficient degree of freedom for it to be able to pivot about an axis perpendicular to the plane containing the first and second axes to bring the rolling surfaces of said first and second elements into engagement.
In another embodiment and according to another subsidiary feature of the invention, the first shaft is rotatably linked to the second element in that the first drive transmission shaft includes a first support plate having as its axis the first axis, and being immovably secured to one end of a support shaft having as its axis the second axis. The other end of the support shaft is immovably secured to a second support plate freely pivotable about the first axis independently of said first support plate, the second element being freely rotatable about the support shaft. Preferably in this embodiment, the support shaft passes through bearings mounted in a cage which is prismatic in its external form, and in turn mounted in said second element with play in the plane containing said first and second axes, but with no substantial play in the direction perpendicular to this plane, whereby the second element is mounted on the support shaft with a sufficient degree of freedom for it to pivot about an axis perpendicular to the plane containing the first and second axes.
When the second element is movable by rotation, with a velocity Wb* about the second axis, it may be rotatably linked to a second shaft in different ways, and all the more simply because the angle of inclination a of the second axis relative to the first axis is substantially constant (excluding the adequate play in certain embodiments giving the second element the required degree of freedom in the radial plane). It may be rotatably linked to the second shaft via a gear-train, constant velocity joint, etc.
More particularly, in certain embodiments a linking gear-train comprises three conical convex gears having a common apex at the point of intersection of the first and second axes, a first of such gears having as its axis the second axis and being mounted for rotation with the second element about the second axis, a second of the gears meshing with the first, and being carried by a shaft on an axis passing through the point of intersection of the first and second axes, the shaft being rotatably mounted by bearings in a satellite support plate in turn rotatable about the first axis. The third of the gears meshes with the second gear and has as its axis the first axis. The third gear is carried by a second drive transmission shaft.
In other embodiments, the linking gear-train comprises two conical convex gears having a common apex at the point of intersection of the first and second axes, a first of these gears having as its axis the second axis and being mounted for rotation with the second element about the second axis. The second of the gear meshes with the first and has as its axis the first axis, the second gear being borne by the second drive transmission shaft.
In a still further embodiment, the linking gear-train includes two conical gears having a common apex at the point of intersection of the first and second axes, a first of the gears being convex and having as its axis the second axis, such first gear being mounted for rotation with the second element about said second axis. The second of these gears meshes with the first and is concave. The second gear has as its axis the first axis and is mounted for rotation with the second drive transmission shaft.
In a still further alternative arrangement, drive transmission shafts are respectively rotatably linked to the angular velocity of the first element about the first axis, the angular velocity of the second element about the second axis, and the angular velocity of nutation of the second axis about said first axis, rotational coupling means being provided between at least two of the shafts.
Such coupling means should be understood in the broadest possible sense of the term. They may comprise, in particular, gear-trains or any other appropriate means enabling the velocities to be linked in a fixed or variable ratio.
These coupling means have particular advantages in the effective deployment of the gyroscopic force couple. As is well known, the gyroscopic couple varies as a function of the angle a and the velocities of the second element about the second axis, and the second axis about the first axis. Consequently, the coupling means enable the evolution of the gyroscopic couple to be modified as a function of the output velocity, thus making it possible to obtain available output couples which are better adapted to different uses (constant couple, constant power, etc.).
In order to permit continuous variation of the ratio of change of the output velocities relative to the input velocities, the transmission device also comprises a means to move the rolling surfaces of at least one of the two pairs axially relative to one another. Operation of this means is simplified because the angle of inclination a of the second axis relative to the first axis is substantially constant and equal to the apex half-angle of the conical surfaces.
In a particular variant, in order to make construction of this means simpler, the first element comprises two parts axially movable relative to each other and on which the two rolling surfaces of the first element are formed, the two parts of the first element being mounted in slidable fashion in a support casing having as its axis said first axis. The means for varying the relative axial position of the two reaction surfaces of the first element comprises a rod parallel to the first axis, such rod having two indentical portions of opposite thread and being rotatable about its axis by a control member. This embodiment is particularly suitable when the first element is rotatable about the first axis and is rotatably linked to a third drive transmission shaft. In this case, it is sufficient to link a support casing in rotational manner with the third shaft. Advantageously, the control means effecting axial displacement of the rolling surfaces of the first element by rotating the rod may be an electric motor.
The invention also contemplates a transmission system comprising at least two transmission devices wherein the transmission devices are coupled in such a way that the resultant of the gryoscopic couples to which the second elements of the transmission devices are subjected is substantially zero. Preferably in this case, three transmissions are mounted in a star shape at intervals of 120° about a general axis of the transmission system, the two movable rolling surfaces of the first elements being common and blocked against rotation on the frame about the said general axis.
In each of the previously mentioned embodiments, at least one of the elements is generally biconical in shape, the respective conical rolling surfaces thus provided on such one element having an apex whose half-angle approximates the angle of inclination of the second axis with respect to the first axis. Due to this arrangement, the angle of inclination of the second axis with respect to the first axis is essentially constant so that the transmission ratio may be varied by movement of the rolling surfaces of the first and second elements axially with respect to each other by sliding them along the generatrix of the cone which is essentially parallel to the corresponding axis of revolution. Nevertheless, it is important in the foregoing embodiments that the second element possess a certain degree of freedom in a direction parallel to the plane containing the first axis and the second axis so that it may be able to pivot against the rolling surface of the first element when it is influenced by the gyroscopic forces.
In a further variation of the invention, the necessity for play in the bearing support for the second element is avoided by employing means for supporting the second element and for fixing the angle of inclination a without any degree of freedom and by employing mechanical means to develop the contact forces by which the respective rolling surfaces are urged into rolling friction engagement and deploying the aforementioned gyroscopic force couple to counterbalance these contact forces. Thus, all of the advantages of the previous embodiments may be retained but with a greatly simplified and more durable bearing system.
As mentioned above, the deployment of the gyroscopic force couple, particularly the effective direction thereof, is accounted for by calculation of the structural and kinematic parameters of the second element. The mechanical system to develop the force necessary to retain the rolling surfaces of the respective first and second elements in frictional contact may take a variety of forms. Generally, such systems are predicated on the ability of relative axial movement of the points of rolling surface contact between the first and second elements and develop a radial force component as a result of the relative axial movement.
It will be appreciated that axial positioning of the points of rolling surface contact may be achieved by (1) actuating the rolling surfaces of the second element, (2) actuating the rolling surfaces of the first element or (3) actuating the rolling surfaces of both elements simultaneously. Such actuation, in turn, may be achieved in several ways, for example:
(a) The mechanical system may be an inertial system, particularly of a type comparable to the gyroscopic means described above. In this case, the geometry of annular rings defining the rolling surfaces on the second element and movable with respect thereto and the profile of the rolling surfaces of the first element are fitted in such a manner as to create two axial forces which are capable of actuating the rolling surfaces of the second element towards the rolling surfaces of the first element with an intensity that is sufficient to exert the specific contact pressure necessary.
(b) The mechanical system may be composed of two elastic systems in which case, the contact pressure created by the elastic system is independent of operational conditions during transient ranges.
(c) The mechanical system may be also composed of a systems of ramps forming part of a shaft that is coaxial with the element considered and works together with the complementary ramps of the rolling surfaces of this element. In this case, these ramps may be helicoidal.
Several embodiments of the invention are described below, by way of example, and with reference to the accompanying drawings, in which like parts are designated by like reference numerals.
FIG. 1 is an axial section of a first embodiment of a transmission device according to the invention;
FIG. 2 is a transverse section on the line II--II in FIG. 1;
FIG. 3 is an axial section of a second embodiment of a transmission device according to the invention;
FIG. 4 is an axial section of a third embodiment of a transmission device according to the invention;
FIG. 5 is an axial section of a fourth, embodiment of a transmission device according to the invention;
FIG. 6 is a transverse section on the line III--III in FIG. 5;
FIG. 7 is a persepective view of the transmission device shown in FIGS. 1 and 2;
FIG. 8 is a perspective view of the transmission device shown in FIGS. 5 and 6;
FIG. 9 is a longitudinal section, cut by a plane passing through the first and second axes, of another alternative embodiment of the invention;
FIG. 10 is a cross-section on line 10--10 of FIG. 9;
FIG. 11 is a longitudinal section, cut by a plane passing through the first and second axes, of a further embodiment like that of FIG. 9 but with an inertial mechanical system;
FIG. 12 is a force diagram illustrating operation of the inertial mechanical system illustrated in FIG. 11;
FIG. 13 is a longitudinal section, cut by a plane passing through the first and second axes, of a still further constructional variation comprising a mechanical system composed of a system of helical ramps;
FIG. 14 is a cross-section on line 14--14 of FIG. 13;
FIG. 15 is a longitudinal section, cut by a plane passing through the first and second axes of still another constructional variation comprising another mechanical system of helixes;
FIG. 16 is a perspective view of the maneuvering component of the variation shown in FIG. 15;
FIG. 17 is a longitudinal section, cut by a plane passing through the first and second axes, of a constructional variation of the type illustrated in FIGS. 10 and 11;
FIG. 18 is a longitudinal section, cut by a plane passing through the first and second axes, of a constructional variation of the type illustrated in FIGS. 13 and 15; and
FIG. 19 is a perspective view of the control component of the constructional variation shown in FIG. 18.
FIG. 20 is a longitudinal section of still another embodiment of a transmission in accordance with this invention;
FIGS. 21, 22 and 23 show respectively, in perspective and on a larger scale, three components of the embodiment of FIG. 20 which differ from similar components of previous embodiments;
FIG. 24 is a longitudinal cross section through one embodiment of an engine incorporating a transmission of the invention;
FIG. 25 is a cross section on line b--b of FIG. 24;
FIG. 26 is a fragmentary cross section on line c--c of FIG. 24;
FIG. 27 is an enlarged fragmentary cross section taken on line d--d of FIG. 24;
FIG. 28 is a cutaway perspective view illustrating the movable components of the embodiment of FIG. 24;
FIG. 29 is a longitudinal cross section taken through an alternative combined engine and transmission of the present invention;
FIG. 30 is a similar cross section illustrating a variant of the embodiment of FIG. 29;
FIG. 31 is a line diagram illustrating the orientation of axes and pivot points of various of the components in the embodiment of FIG. 29; and
FIG. 32 is a longitudinal cross-section of a structural variation of the embodiment of FIGS. 29-31.
The device according to the invention shown in FIGS. 1, 2 and 7 comprises a second element 3 having two conical convex surfaces 19, 20, r 1 (=∞) and r 3 designating the radii of curvature of the surface considered in a meridian plane passing through second axis 12 and in a transverse plane orthogonal to the first, respectively, disposed about second axis 12. These two conical surfaces 19, 20 are both symmetrical relative to a point S located on the second axis 12. Each of these conical surfaces 19, 20 is in frictional contact with a respective one of two annular concave rolling surfaces 8, 9, being of convex toric section in the peripheral direction, r 2 and r 4 designating the radii of curvature of the surface considered in a meridian plane passing through a first axis 7 and in a plane orthogonal to the first, respectively. These surfaces are formed on two parts 4, 5 respectively of a first element 2; the two surfaces 8, 9 are disposed about a first axis 7 and are both symmetrical relative to the point S also located on the first axis 7. The conical surface 19 of the element 3 and the surface 8 of the element 2 make contact at a single point P1 located on the surface 19. The conical surface 20 of the element 3 and the surface 9 of the element 2 make contact at a single point P2 located on surface 20. These two points of contact (P1, P2) are symmetrically disposed relative to the point S. The axes 12 and 7 which intersect at the point S are inclined relative to each other at an angle a.
The second element 3 is drawn in a movement defining a cone with axis 7 and with an angle 2a at the apex S, under the influence of a first shaft 18 coaxial with the axis 7. For this purpose, the shaft 18 pivots about the axis 7 in the casing 1, 97, 105, 107 via bearings 27 and 30 and includes two plates 18a and 18b having an axis coaxial with the axis 7, the plates being connected to each other by a truncated cylindrical portion 18c passing round the element 3. The two plates 18a and 18b support two half-shafts 50 and 51 respectively, coaxial with axis 12 and mounted for rotation with the element 3. These half-shafts 50 and 51 are mounted in the plates 18a and 18b via bearings 14, for example, needle bearings. The bearings 14 consequently permit the second element 3 to rotate freely about axis 12 while being drawn into conical rotation by the plates 18a and 18b.
The external cages of the bearings 14 include sleeves 15 mounted in the plates 18a, with play in the plane containing the axes 7 and 12 and in a direction perpendicular to the axis 12. This gives the element 3 a degree of freedom enabling it to pivot about the axis 22 passing through S and perpendicular to the rotating plane of the axes 7 and 12, under the effect of the gyroscopic couple about axis 22 (in the direction of the arrow f) to which the element 3 is subjected owing to its nutational or conical movement. This causes surfaces 19 and 20 of the element 3 to contact, at points P1 and P2 respectively, surfaces 8, 9 of the element 2. The two surfaces 8, 9 of the element 2 are formed, respectively, on radial portions 4a, 5b, of the two parts 4, 5 of the element 2. These two parts 4, 5 of the element 2 are mounted for rotation about the axis 7, by means of keys 4d, 5d with an element 1, forming a cylindrical casing with axis 7, which is secured on one side at 98 to a lid 97 and on the other side at 99 to a hollow shaft 105, or third shaft, secured at 106 to a flange 107, having axis 7.
The casing rotates freely about the axis 7, in the frame A via bearings 29 and 31, and about the shaft 18 and hollow cylindrical extension 18d of the plate 18b via bearings 27 and 30. The element 3 is rotatably linked to a shaft 21, or a second shaft, with axis 7, via three conical convex gears having a common apex S. The first of these gears, 47, has as its axis the axis 12 and is mounted for rotation with the element 3 about axis 12 by being attached to the half-shaft 51. This gear 47 is moreover drawn by the shaft 51 in the conical movement which the element 3 undergoes about the axis 7. Gear 47 cooperates with a second gear 45 which acts as an intermediary and which is carried by a shaft 46, the axis of which passes through S. This shaft 46 is carried by the plate 18b, and is therefore drawn by the latter about the axis 7 while rotating freely about its axis via bearings housed in the plate 18b. In FIG. 1, the axis of this shaft 46 is not shown. This second gear 45 co-operates with a third gear 44 of the linking gear-train. This third gear 44 has as its axis the axis 7 and is carried on the end of the second shaft 21 to constitute the central planetary arrangement of the linking gear-train. The shaft 21 rotates freely about axis 7 in the cylindrical extension 18d of plate 18b, via bearings 40. The three shafts 18, 21 and 105-107 of the variator may or may not rotate, may or may not be coupled to one another by mechanical connections (gears, etc.), and may each have one of the three functions of input, output or reaction.
The two parts 4, 5 of the element 2 are axially movable relative to one another along the axis 7 and movable symmetrically relative to the plane 10 perpendicular at S to the axis 7. Thus, the points of contact P1, P2 remain symmetrical relative to the point S so that the ratio R1:R2 is always identical at these two points. In this particular case, the casing 1 being rotational about the axis 7, the means used for varying the axial spacing of the parts 4, 5 is an electric micromotor M fixed on the casing 1. Motor M is controlled from outside the casing by push-buttons B1, B2 connected to a source of electric current, and which co-operate via rods T1, T2 with annular conducting tracks D1, D2, with axis 7, formed in the lid 105. These tracks are connected to the motor M by conducting wires passing through the cylindrical wall of the casing 1. The motor M drives a rod, the axis of which is parallel to the axis 7, formed of two threaded parts with an identical but opposite thread at 48 and 49, which co-operates with the two parts 4, 5 of the element 2. Depending on whether B1 or B2 is pressed, the motor M drives the rod 48, 49 in one direction or the other, in order to simultaneously move the two parts 4, 5 of the element 2 away from or towards each other.
FIG. 2 represents a section through FIG. 1 on a plane passing through the point of contact P2 and perpendicular to the meridian plane of the axes 7 and 12 (the line II--II in FIG. 1). This figure shows the radii of curvature r3 and r4 transverse to the point of contact.
FIG. 3 represents a mechanical speed variator which comprises two biconical convex elements 3A and 3B each in contact, at two points P1, P2, and P3, P4 respectively, with two sets of annular surfaces 8A, 9A, and 8B, 9B, formed on the two parts 4A and 4B. The two elements 3A and 3B are mounted opposite each other on the same bent shaft forming a crank-shaft and having two parts 51A and 51B, with axes 12A and 12B inclined at equal but opposite angles a to the axis 7. These elements 3A and 3B are drawn about the axis 7 in conical movement having apices SA and SB with apex angles 2a, by a common shaft 18, or first shaft coaxial with the axis 7. This shaft 18 is pivotably mounted in the casing 1-105 via bearings 27, to form a drive input or output.
For this purpose, the two parts 51B and 51A are carried by two support plates 71 and 63. The plate 71 extends the shaft 18 and receives the end of the shaft 51B, joining it at 55. The plate 63 is freely mounted for rotation about axis 7 via bearings 78 and receives the end of the shaft 51A, joining it at 54. Each element 3A and 3B has a sufficient degree of freedom to pivot about respective axes 22A and 22B passing through points SA and SB and perpendicular to the rotating plane containing the axes 7, 12A and 12B. This degree of freedom is obtained by mounting the bearings 14A and 14B which support the elements 3A and 3B on the shafts 51A and 51B, in outer cages 56A and 56B which are prismatic (e.g. squares) in cross section. These cages 56A and 56B are housed in the elements 3A and 3B with some play in the meridian plane and in the direction perpendicular to the axes 12A and 12B respectively. The gyroscopic couples to which the elements 3A and 3B are subjected (arrows fA and fB) press the element at the points of contact P1, P2, P3, P4, against the annular surfaces of the elements 2A and 2B. These annular surfaces are locked against rotation about axis 7, for they are mounted for rotation with a common casing 1-105-97 which is itself fixed.
By reaction, the elements 3A and 3B rotate about their respective axes 12A, 12B, with identical angular velocity and in the same direction. The two elements 3A and 3B are linked in rotation by conical gears 69 and 70 and rotatably connected to a common shaft 21 (or second shaft) having axis 7 for its axis, which rotates in 97 via bearings 57, to form a drive input or output. The rotational connection between the shaft 21 and the element 3A is effected by two conical gears having a common apex SA, the first 47 being convex, with apex 12A and formed in 3A, the second 53, which co-operates with 47 at 52, being concave, with axis 7 and secured at 60 to the shaft 21 for rotation therewith to form the outer crown of the linking gear-train. This crown 53 is held in the casing 1 by bearings 62.
The surfaces 8A and 9A are symmetrical relative to the plane 10A, and the surfaces 8B and 9B are symmetrical relative to 10B. Since the casing 1 is fixed, the speed variation may be controlled directly from outside, either manually or by electric means or the like. The arrangement with two biconical elements 3A and 3B is used so that the resulting gyroscopic couple on the frame is substantially zero. It should be noted that the four points of contact P1, P2, P3, and P4 all work in parallel, not in series, in power transmission.
FIG. 4 shows a mechanical variator which is different from that in FIG. 3 only in that the second shaft 21 is locked against rotation, being in effect portion 65 of the frame A, while the first shaft 18, mounted in bearings 67, still constitutes an input or output shaft 18 secured to plate 71 which is mounted in bearings 66 carried by the casing. A third shaft 105 mounted in bearing 29 and being an extension of the casing, rotates and constitutes an input or output. Communication of the conical movement by the shaft 18 to the two elements 3A and 3B, the mountings of the elements 3A and 3B providing a degree of pivotal freedom, and the gear-train with two conical gears forming a link with the shaft 21 (i.e. casing portion 65) are equivalent to those described in FIG. 3. Since the casing 1 rotates, the speed variation is controlled by means of a micro-motor M.
FIGS. 5, 6 and 8 show a transmission consisting of 3 biconical elements 3A, 3B 3C mounted in a star shape, spaced by 120° from each other about common general axis 7. Thus the resultant of the 3 gyroscopic couples communicated by the three elements 3A, 3B and 3C to the two common parts 4 and 5 and then from these parts 4 and 5 to the casing 1 is substantially zero. Each of these three elements 3A, 3B, 3C is drawn in a conical movement with an apex angle 2a about its respective axis 7A, 7B, 7C parallel to the general axis 7. For this purpose, each of the elements 3A, 3B, 3C is mounted on a shaft 51A, 51B, 51C inclined to the respective axis 7A, 7B, 7C, each of these shafts being supported by two plates 71A and 63A, 71B and 63B, 71C and 63C, respectively, as in the arrangement in FIGS. 3 and 4.
Each of the elements 3A, 3B, 3C has the necessary degree of freedom for pivoting about the axes 22A, 22B, 22C, since they are mounted on bearings 14A, 14B, 14C in an identical manner to that shown in FIGS. 3 and 4. Each element 3A, 3B, 3C abuts, at a fifth point on the annular, concave, toric surface corresponding thereto, the surfaces being 8A with axis 7A, 8B with axis 7B, and 8C with axis 7C respectively, and at a second point on surface 9A with axis 7A, 9B with axis 7B, and 9C with axis 7C respectively. The three annular surfaces 8A, 8B, 8C are formed by cutouts spaced at 120° intervals, in a common member 4 with axis 7, and the three annular surfaces 9A, 9B, 9C are similarly cut out in a member 5 also with axis 7. Members 4 and 5 are secured at 4d and 5d to an intermediate cylindrical casing 1e, with axis 7, for rotation therewith about axis 7, this casing in turn being secured at 79 to a general casing 1-97-105 also with axis 7.
In this arrangement, the casing 1-105 is locked against rotation about the axis 7, and thus the two parts 4 and 5 are also locked against rotation about this axis, although being axially movable relative to the axis 7 and remaining symmetrical relative to the plane 10, for the purpose of speed variation. Independent plates 63A, 63B, and 63C are freely mounted for rotation about their respective axes via bearings 78A, 78B, 78C, carried by a fixed support plate 80 with axis 7 and fixed at 81 to the intermediate casing 1e. The plates 71A, 71B, 71C are mounted in bearings 67A, 67B, 67C on a fixed support plate 94 with axis 7, fixed at 79 to the casing 1. The three shafts 18A, 18B, 18C of these plates 71 rotate at the same speed and in the same direction about their respective axes 7A, 7B, 7C, by being rotatably linked by gears 76A, 76B, 76C to a gear 71 provided on the shaft 18, which constitutes an input or output in this arrangement. This shaft 18 is rotatably mounted in the casing 1-105 by means of bearings 27.
By reaction, at six points of contact on the six annular surfaces 8A, 9A, 8B, 9B, 8C, 9C, the three elements 3A, 3B, 3C rotate about their respective axes 12A, 12B, 12C at the same speed and in the same direction. Each of these three elements 3A, 3B, 3C is linked in rotation to common shaft 21 with axis 7, which is rotatably mounted in the casing 97-1-105 by means of bearings 57. This rotational linking is provided by conical gears 91A, 91B and 91C having apices SA, SB, SC and axes 7A, 7B, 7C, respectively, carried by annular pieces 90A, 90B, 90C with axes 7A, 7B, 7C respectively. Three gears 91A, 91B and 91C co-operate with conical gear teeth 93A, 93B, 93C having apices SA, SB, SC and axes 12A, 12B, 12C respectively, which are formed in the two conical halves of each of the elements 3A, 3B, 3C.
The annular pieces 90A, 90B and 90C co-operate via gears on their periphery with gear teeth 89 of a crown 88 with axis 7, said crown being mounted for rotation about axis 7 with the shaft 21, via sections 87, 86 and 85. It should be noted that the six points of frictional contact of this arrangement all work in parallel, and not in series in power transmission.
FIG. 6 represents a section through the transmission device in FIG. 5, on a plane perpendicular to the axis 7 and passing through three of the points of contact (line III--III in FIG. 5) FIG. 5 is a biradial section on the line IV--IV in FIG. 6.
In each of the embodiments thus described, the rolling surfaces of the first and second elements are pressed against each other solely by the aforementioned gyroscopic force couple with sufficient force to enable the transmission of constant high power without need for additionally supporting the rolling surfaces and without producing axial reaction forces.
FIGS. 9 and 10 show a longitudinal view and a cross-sectional view, respectively, of an alternative embodiment of the invention and in which the gyroscopic force couple previously described is deployed to counterbalance a mechanically developed force for frictional rolling engagement of the elements of the transmission. This transmission includes a fixed frame 200 composed of two essentially flat sides 200A and 200B at the end of the frame joined by a crankcase 200C of an approximately cylindrical shape. The frame thus constituted supports a first element 202 and a second element 203.
The first element 202 is rotatable around a first axis 207, which is the longitudinal axis of the transmission and is fixed with respect to frame 200. The first element is composed of two half-sections 204 and 205 defining two conically shaped rolling surfaces 208 and 209. The two half-sections are mounted on a shaft 211 (output shaft) which is coaxial with the first axis 207 and are axially movable with respect to each other in the longitudinal direction of the first axis 207. Keys 222a and 222b lock the two half-sections 204 dto of magnitude and of an order of magnitude indicated by the transverse dimensions of the transmission. The radius of this curvature is about equal to between 10 and 100 times the maximum transverse diamter of the rolling surfaces of the second element.
In a variant shown in FIG. 30, components described with reference to FIG. 29 are designated by reference numbers and no further explanation of such components is believed necessary. In this instance, two of the cylinders and pistons are located symmetrically in relation to point S. The extensions 821 are therefore mounted at opposite ends of the second element 807. This symmetrical position of the cylinders augments synchronization of their thermal cycle. In particular, this head-to-foot position of the cylinders allows an automatic compensation of the axial component of the piston thrust. Consequently, the system of links 825 and 826 described previously is not needed.
Otherwise, the functioning of this transmission is comparable, if not identical, to that of the first solution.
This invention has been illustrated in detail by two solutions for construction of a heat engine. It is obvious that the present invention covers any other coupling means having reciprocating motion. Specifically, in place of the receiver shaft 801 may be a motor shaft and the pistons 822 may be those of a compressor.
In FIG. 32, a constructional variation of the linkage and transmission of FIGS. 29-31 is combined with a Sterling engine. The reference numeral 951 thus generally designates the heat engine which employs the Sterling cycle previously described with respect to FIG. 24. In FIG. 32, most of the components already described in relation to FIGS. 24-31 are shown in FIG. 32 and designated by reference numerals having the same ten and unit integers but in a 900 series. The ensuing description, therefore, will be confined to the connections between the inwardly curved extensions 920 and 921.
It is to be noted with respect to FIG. 31, that the projecting ends of the extension describe a path around axes 843 and 844 of the cylinders which defines a circle when projected on a transverse plane and having a diameter D in the formula D=E (1-cos a) where E represents the distance between the axis 843 of the cylinder and the first axis 840. It is desirable, if not dispensable, therefore, to either design the joint of the projecting ends of the bell-crank like extensions in such a manner that the center of the joint will describe a circle around the axis of the piston or to design the piston in such a manner that the center of the joint will describe a circle around the axis of the piston or to design the piston in such a manner that the assembly of extension, joint and piston can describe a circle around the axis of the cylinder. Such a design may reside theoretically in providing a cylinder whose diameter is slightly larger than that of the piston in accordance with the above formula.
Thus in FIG. 32, dynamic coupling devices are shown to include a slide 989 which is at least partially cylindrical. This slide glides along the axis of the cylinder of the heat engine with a guide 990 which is at least partially cylindrical. The diameter of the slide is slightly smaller than the diameter of the guide. This difference in diameter is equal to D and is given by the formula D=E (1-cos a). The slide assembly is mounted at the end of the rod 933 that is connected to the piston 930 of the heat engine. It is mounted in such a manner that the slide can move freely in a transverse plane while still being linked with the rod in an axial direction. On the slide is mounted (in a well-known manner) a Cardan joint, one of whose parts is connected to the end of extension 921, the center of the Cardan joint being located in plane 942. Due to the ability of the slide to move laterally, it can follow the circular motion of the end of extension 921 while still being supported by one of its generatrices in cylindrical guide 990. Thus, the second element is constrained to rotate together with the frame. (Wb=0 and Wb*=Wa).
Thus it will be seen that by the foregoing inventions there is provided a highly effective transmission having broad application to many uses and environments. That the invention may be manifested by numerous and diverse specific embodiments is evident from the numerous embodiments described. It is contemplated, however, that still further variations of the transmission as disclosed herein will be apparent to those skilled in the art from the preceding description. For example, it is fully within the contemplation of the present invention that the aforementioned generally conical surfaces be located on the innermost surface of the outermost cylindrical element rather than on the element which is positioned inside of such cylindrical element. Similarly, while the preferred embodiments of the present inventions are all restricted to a structure in which one of the first or second elements has rolling surfaces which, generally speaking, are the surfaces of cones having an apex half-angle equal to or slightly smaller than the angle of intersection of the first and second axes, certain features of the present inventions are themselves novel and patentable per se without regard to such conical arrangement. An example of such a per se novel feature is the provision for eliminating the degree of freedom of the second element so as to prevent it from pivoting about the point of axes intersection, the result of such freedom being to utilize the gyroscopic couple to counterbalance forces by which the rolling surfaces are held in frictional contact by mechanical means. Such feature could, accordingly, be used with advantage not only in the conical transmissions of the present application but in transmissions such as are disclosed in applicant's aforementioned U.S. Pat. No. 3,955,432. A further example of a per se novel feature is the use of a reciprocable input in combination with applicant's transmissions. While such reciprocable input is preferably used in combination with the conical arrangement described in the instant specification, it can also be used with transmissions such as are described in applicant's U.S. Pat. No. 3,955,432. Accordingly it is expressly intended that the described embodiments are exemplary only, not limiting, and that the true spirit and scope of the present inventions be determined by reference to the appended claims.
| Patent | Priority | Assignee | Title |
| 4369667, | Jul 10 1981 | CATERPILLAR TRACTOR CO | Traction surface cooling method and apparatus |
| 4495829, | May 19 1980 | IPANEMA COMPANY, A MI LIMITED PARTNERSHIP | Power drive line having a wide range of speed ratios |
| 4572015, | Apr 04 1984 | CATERPILLAR INC , A CORP OF DE | Nutating traction drive transmission |
| 4630494, | Jan 25 1985 | TRACTIONTEC CORP , A MICHIGAN CORP | Radially oriented nutational traction drive transmission |
| 4745821, | Nov 21 1986 | Bloomfield Research Limited Partnership | Speed ratio adjusting system for nutational traction drive transmissions |
| 7411312, | May 31 2002 | SHEPPARD, MULLIN, RICHTER & HAMPTON LLP | System and method for powering accessories in a hybrid vehicle |
| 7492055, | May 31 2002 | SHEPPARD, MULLIN, RICHTER & HAMPTON LLP | System and method for powering accessories in a hybrid vehicle |
| 7690451, | May 31 2002 | SHEPPARD, MULLIN, RICHTER & HAMPTON LLP | System and method for powering accessories in a hybrid vehicle |
| 9587721, | Oct 20 2011 | Infinitely variable traction drive employing alternate steerable rollers |
| Patent | Priority | Assignee | Title |
| 1771806, | |||
| 1981910, | |||
| 2178399, | |||
| 2203637, | |||
| 2319319, | |||
| 2328536, | |||
| 2405957, | |||
| 2457431, | |||
| 2535409, | |||
| 2682776, | |||
| 2974547, | |||
| 3108496, | |||
| 3207004, | |||
| 3224285, | |||
| 3224300, | |||
| 3242748, | |||
| 3261219, | |||
| 3298238, | |||
| 3302474, | |||
| 3413864, | |||
| 3677109, | |||
| 3793910, | |||
| 3955432, | Jul 13 1973 | Vadetec S.A. | Transmission device |
| AU151142, | |||
| FR1227486, | |||
| JP4628931, | |||
| JP4628932, |
| Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
| Jun 13 1979 | Vadetec Corporation | (assignment on the face of the patent) | / | |||
| Oct 22 1982 | IPANEMA LIMITED, A PRIVATE COMPANY OF THE BRITISH VIRGIN ISLANDS | IPANEMA COMPANY, A MI LIMITED PARTNERSHIP | ASSIGNMENT OF ASSIGNORS INTEREST | 004190 | /0879 | |
| Mar 07 1983 | IPANEMA COMPANY, 525 NORTH WOODWARD AVE , STE 2300, BLOOMFIELD HILLS, MI 48013 A MI LIMITED PARTNERSHIP | ISHIKAWAJIMA-SHIBAURA MACHINERY CO , LTD , 6-8, 1-CHOME, NISHISHINJUKU, SHINJUKU-KU, TOKYO 160, JAPAN A CORP OF | LICENSE SEE DOCUMENT FOR DETAILS | 004196 | /0382 | |
| Aug 11 1983 | VADETEC CORPORATION, | IPANEMA LIMITED, A CORP OF BRITISH VIRGIN ISLANDS, | LICENSE SEE DOCUMENT FOR DETAILS | 004192 | /0408 | |
| Apr 19 1984 | Vadetec Corporation | CATERPILLAR TRACTOR CO | ASSIGNMENT OF ASSIGNORS INTEREST | 004289 | /0254 |
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