Wheel for a track laying vehicle

Abstract

A road wheel for a track laying vehicle comprising a metallic disc and rim part wherein the rim portion of the part is of toroidal geometry. An elastomeric tire tread part is bonded to the outer surface of the rim part and has a tread with a cylindrical outer face adapted for engagement with the track treads of the track laying vehicle. The cross sectional thickness of the metallic disc and rim part is substantially uniform throughout the same. The rim portion has a radially in-turned flange at the free end thereof extending at an acute angle to the axis of the road wheel. The disc portion merges with the rim portion integrally through a bend portion and extends radially inwardly a given distance to provide a track lug wear surface. The disc portion also has a reverse bend offset axially toward the outer free edge of the rim portion to provide clearance for track guide lugs in the operation of said wheel. The rim portion has a radius of curvature taken in radial cross section in a plane including the wheel axis generally equal to the radius of the disc-rim wheel part measured in a plane at right angles to the wheel axis from the wheel axis to the other curved surface of the rim part. The tire tread has axially opposite sloping side walls inclined in a radially inward divergent relationship to one another. A method of making the road wheel is also disclosed.

Description

This is a continuation Ser. No. 06/869,388, filed on 05/30/86 now abandoned .

The present invention relates to wheels for track laying vehicles and, more particularly, to improvements in road wheels for military tanks and other heavy track laying vehicles.

In track assemblies of crawler-type vehicles a plurality of wheels are provided in a tandem row on each side of the vehicle to contact and run upon the associated track and carry the vehicle weight through the associated suspension systems. One type of known track or bogie wheel assembly comprises a dual wheel set in which two wheels, each having a mounting disc or body and a peripheral rim, are mounted back-to-back onto a hub or spindle, and solid elastomeric tread treads significantly reduces the maximum stress concentrations in the rubber tire, and the toroidal shape of the rim section likewise minimizes maximum stress concentrations and improves the strength to weight ratio of the metal part of the wheel. Overall reduction in weight or an improvement in strength to weight ratio is thus obtained by the present invention in a very economical fashion.

Although the present invention is particularly designed and adapted for use with military-type armored or heavy track laying vehicles, it should be understood that the invention may be used with other types of crawler vehicles, such as those utilized in earth moving operations.

In one working example of the present invention constructed in accordance with FIGS. 1 through 4 of the drawings, wheel embodiment 20 is made to the following specifications:

EMBODIMENT SPECIFICATIONS

______________________________________
Embodiment Specifications
______________________________________
Overall wheel diameter  25.00"
Radius of rim 40 measured to its
11.81"
outer surface apex
Radius of curvature of toroidal rim section
11.12"
40 in the axial plane of the drawing
Angle of flange 44 relative to axis 58
55°
of the wheel
Minimum radial thickness of tread tire 50
.94"
Maximum axial dimension of tread tire 50
6.81"
Axial dimension of flat tread surface 52
5.73"
tread tire 50
Composition of tread 50 per MIL-W-3100
or equivalent
______________________________________

EMBODIMENT SPECIFICATIONS ______________________________________ Embodiment Specifications ______________________________________ Material specification of disc-rim part 22 SAE 950 HSLA Mod. Radius of curvature of bend 42 1.06" Radius of curvature of bend 38 1.06" Radius of curvature of reverse backbone 32 1.20" Thickness of steel stock in disc-rim part 22 .300 min" ______________________________________

In accordance with another working example of the wheel constructed in accordance with the present invention pursuant to the alternate wheel embodiment 100 of FIGS. 5, 6,and 7, the following specifications were employed:

EMBODIMENT SPECIFICATIONS ______________________________________ Embodiment Specification ______________________________________ Overall wheel diameter 28" Radius of rim 40' measured to its 12.95" outer surface apex Radius of curvature of toroidal rim 4.35" section 40' in the axial plane of the drawing Radius of curvature of bend 42' .735" Angle of flange 44' relative to axis 58 35° of the wheel ______________________________________

PAC EMBODIMENT SPECIFICATIONS ______________________________________ Minimum radial thickness of tread tire 104 (28"-25.90") Maximum axial dimension of tread tire 104 3.66" Axial dimension of flat tread surface 108 3.25" of tread tire 104 Composition of tread tire 104 per MIL-W-3100 or equiv Material specification of disc-rim part 102 SAE 950 HSLA modified Radius of curvature of bend 38' .59" Radius of curvature of reverse backbone 106 1.46" Thickness of steel stock in disc-rim part 102 .229" min ______________________________________

It will also be understood that, although the foregoing description and drawings describe and illustrate in detail successful working embodiments of the present invention, to those skilled in the art to which the present invention relates the present disclosure will suggest many modifications in construction as well as widely differing embodiments and applications without hereby departing from the spirit and scope of the invention. The present invention, therefore, is intended to be limited only by the scope of the appended claims and the applicable prior art.

Claims

1. A support wheel for a vehicle comprising a disc part and a rim part , said rim part having a rim portion of toroidal geometry, said rim portion toroidal geometry being defined by a radially outermost surface of said rim portion having a uniform radius of curvature taken in radial cross section in a plane including the axis of rotation of said wheel and being symmetrical about a radially outermost apex of said toroidal rim portion, said rim portion being joined to and extending generally axially from the radially outermost portion of said a disc portion of said part and having at least only one free end portion spaced axially of si said wheel remote from said radially outermost portion of said disc portion, and a non-pneumatic elastomeric tire tread part having a curved inner surface complimentarily matching and being bonded to said outermost surface of the said rim portion and centered on ad and also being symmetrical about the apex of said toroidal rim portion, said tire comprising a tread having a smooth circumferentially continuous cylindrical tread outer face adapted for engagement with a hard, flat supporting surface for the vehicle.

2. A wheel as set forth in claim 1 wherein the cross sectional thickness of said rim portion is substantially uniform throughout the same.

3. A wheel as set forth in claim 2 wherein said rim portion has a radially in-turned flange at said one free end thereof extending convergently toward said disc portion at an acute angle to the axis of the road wheel.

4. A wheel as set forth in claim 3 wherein said radially in-turned flange angle ranges between about 35° to 55°.

5. A wheel as set forth in claim 4 for use as a road wheel with a track laying vehicle having track treads which define the hard flat supporting surface for the vehicle, said tire tread being adapted for engagement with the track laying vehicle track treads, and wherein said disc portion merges with said rim portion integrally through a bend portion and extends radially inwardly a given distance to provide a track lug wear surface, said disc portion having a reverse bend portion merging with said wear surface portion and being offset axially toward the outer free edge of the rim portion to provide clearance for track guide lugs in the operation of said wheel, said reverse bend portion also merging with a wheel hug mounting portion in the central area of said disc part, said wheel hub mounting portion being offset axially farther from the free end of said rim port portion than said radially extending disc wear surface portion.

6. A road wheel as set forth in claim 5 wherein said tire tread has axially opposite sloping side walls inclined in a radially inward divergent relationship to one another.

7. A road wheel as set forth in claim 6 wherein the one of said tire tread side walls closest to the wheel hub mounting portion of said disc-rim part terminates at its radially inwardly edge with a slight axially outward offset from the junction of the rim portion with the disc portion of said disc and rim part.

8. A road wheel as set forth in claim 6 wherein said side walls slope at an angle to the axis of the wheel ranging from about 3° to 7°.

9. A wheel as set forth in claim 2 wherein said radius of curvature is generally equal to the radius of the disc-rim wheel part measured in a plane at right angles to the wheel axis from the wheel axis to said outer curved surface of said rim portion.

10. The wheel as set forth in claim 2 wherein said tire tread has axially opposite side walls extending radially inwardly from said tread outer face to respective junctions with said rim portion outermost surface, and wherein the ratio of the minimum thickness of said tire tread radially of the wheel to the maximum radial dimension of said tread tire measured from said cylindrical outer face of the tread to the junction of the side walls of the tread tire with the rim portion of the disc-rim part is approximately 1.2.

11. A wheel as set forth in claim 10 wherein the ratio of the uniform radius of curvature of said radially outermost surface of said rim portion of the maximum axial dimension of said tire tread is in the range of about 11.12:6.81 to about 4.35:3.66.

12. A wheel as set forth in claim 4 wherein said wheel is adapted for use as a road wheel on a track laying vehicle having track treads which define the supporting surface for the vehicle, said tire tread being adapted for engagement with the track treads of the track laying vehicle and said cylindrical outer face of said tire tread is adapted for engagement with the treads of the track of the track laying vehicle.

13. The wheel as set forth in claim 12 wherein said tire tread has axially opposite side walls extending radially inwardly from said tread outer face to respective junctions with said rim outermost surface, wherein the ratio of the minimum thickness of said tire tread radially of the wheel to a maximum radial dimension of said tread tire measured from said cylindrical outer face of the tread to the junction of the side walls of the tread wit tire with the rim portion of the disc-rim part is approximately 1:2 and wherein the ratio of the uniform radius of curvature of said radially outermost surface of said rim portion to the maximum axial dimension of said tire tread is in the range of about 11.12:6.81 to about 4.35:3.66.

14. The wheel as set forth in claim 13 wherein said radius of curvature is generally equal to the radius of the disc-rim wheel part measured in a plane at right angles to the wheel axis from the wheel axis to said outer curved surface of said rim portion.

15. The wheel as set forth in claim 13 wherein said tire tread side walls are inclined in a radially inward divergent relationship to one another.

16. The wheel as set forth in claim 11 wherein said disc and rim parts are formed integrally as one piece from sheet metal, said rim portion extending generally axially in only one direction from the radially outermost portion of said disc part to said one free end portion so as to be cantilevered from said disc part.

17. The wheel as set forth in claim 13 wherein said disc and rim parts are formed integrally as one piece from sheet metal, said rim portion extending generally axially in only one direction from the radially outermost portion of said disc part to said one free end portion so as to be cantilivered from said disc part.

18. The wheel as set forth in claim 15 wherein said disc and rim parts are formed integrally as one piece from sheet metal, said rim portion extending generally axially in only one direction from the radially outermost portion of said disc part to said one free end portion so as to be cantilivered from said disc part.

19. A one piece metal support wheel for a vehicle comprising a metallic disc and rim part having a vehicle mounting disc portion and a non-pneumatic tire mounting rim portion of toroidal geometry, said rim portion toroidal geometry being defined by a radially outermost convex surface of said rim portion having a generally uniform radius of curvature taken in radial cross section in a plane including the axis of rotation of said wheel, said outermost surface of said rim portion extending generally axially from the radially outermost portion of said disc portion of said disc and rim part to a radially in-turned free end flange portion of said rim portion spaced axially of said wheel remote from said disc portion, said rim portion extending generally axially in only one direction from the radially outermost portion of said disc portion to said free end flange portion so as to be cantilevered from said disc portion, said disc portion merging with said rim portion integrally through a bend portion in said radially outermost portion of said disc portion and extending radially inwardly therefrom to define a bolt circle mounting portion of said disc portion adapted for removable mounting of said wheel via wheel fastener means to a vehicle wheel mounting part, said rim portion outermost surface being disposed radially outwardly of said bend portion and adapted to receive thereon by bonding thereto a non-pneumatic tire having a tread defining an outer peripheral surface adapted for engagement with a supporting surface for the vehicle. 20. A wheel as set forth in claim 19 wherein said radially in-turned flange portion extends convergently toward said disc portion at an acute angle to the

axis of the road wheel. 21. A wheel as set forth in claim 20 wherein said radially in-turned flange portion acute angle ranges between about 35° to about 55°. 22. A wheel as set forth in claims 20 and 21 wherein said wheel is formed from sheet metal such that the cross sectional thickness of said rim portion is substantially uniform throughout at least a major portion of the same. 23. A wheel as set forth in claim 21 for use with a track laying vehicle having track treads which define a hard flat supporting surface for the vehicle, said wheel further including a tire part having a tread defining an outer peripheral surface adapted for engagement with the track laying vehicle track treads, said tire having an inner surface complimentarily matching and being bonded to said outermost surface of said rim portion. 24. A wheel as set forth in claim 23 wherein said disc portion extends radially inwardly a given distance from said bend portion to provide a track lug wear surface, said disc portion having a reverse bend portion merging with said wear surface portion and being offset axially toward the outer free edge of the rim portion to provide clearance for track guide lugs in the operation of said wheel, said reverse bend portion also merging with said wheel mounting portion in the central area of said disc and rim part, said wheel hub mounting portion being offset axially farther from the free end of said rim portion than said radially extending disc wear surface portion. 25. A wheel as set forth in claim 23 wherein said tire has axially opposite sloping side walls inclined in a radially inward divergent relationship to one another. 26. A wheel as set forth in claim 25 wherein the one of said tire side walls closest to the vehicle wheel mounting part terminates at its radially inwardly edge with a slight axially outward offset from the junction of the rim portion with the disc portion of said disc and rim part. 27. A wheel as set forth in claim 25 wherein said side walls slope at an angle to the axis of the wheel ranging from about 3° to 7°. 28. A wheel as set forth in claim 23 wherein said outer peripheral surface of said tire tread is cylindrical, and wherein the radio of the minimum thickness of said tire radially of the wheel to the maximum radial dimension of said tire measured from said cylindrical outer tread face to the junction of side walls of the tire with said rim portion of said disc

and rim part is approximately 1:2. 29. A wheel as set forth in claim 23 wherein the ratio of the uniform radius of curvature of said radially outermost surface of said rim portion to the maximum axial dimension of said tire is in the range of about 11.12:6.81 to about 4.35:3.66. 30. A wheel as set forth in claim 19 wherein said radius of curvature is generally equal to the radius of said disc and rim part measured in a plane at right angles to the wheel axis from the wheel axis to said outer curved surface of said rim portion. 31. A wheel as set forth in claim 20 further including a non-pneumatic elastomeric tire part having an inner surface complimentary matching and being bonded to said outermost surface of the rim portion and having an outer tread surface adapted for engagement with a supporting surface for the vehicle. 32. A wheel as set forth in claim 31 wherein said tire tread outer surface comprises a generally cylindrical outer tread face adapted for engagement with the supporting surface for the vehicle. 33. A wheel as set forth in claim 31 wherein said rim portion convex surface is generally symmetrical about an apex of

the arch of said toroidal rim portion. 34. The wheel as set forth in claim 33 wherein said radially in-turned flange portion acute angle ranges between about 55° to about 35°. 35. The wheel as set forth in claim 33 wherein said tire is generally centered on and also generally symmetrical about the apex of said toroidal rim portion. 36. The wheel as set forth in claim 35 wherein said wheel is formed from sheet metal such that the cross sectional thickness of said rim portion is substantially uniform throughout at least as major portion of the same.