Methods for handling masa

Abstract

Mass handling methods for the continuous processing of masa type dough in conjunction with commonly available feed processing equipment, such as a masa extruder, an oven, or cooling apparatus. One masa handling method includes a masa separator having a pair of opposed, endless belt conveyors having facing surfaces spaced apart to receive a generally continuous masa stream output from a nozzle on the masa extruder. When the masa stream moves between the conveyors, it is gripped by their facing surfaces and moved away from the nozzle, causing the masa to be separated into individual pieces, or logs. The masa handling method can also include feeding the masa to masa hoppers fed by at least two endless belt conveyors arranged in upstream and downstream positions relative to each other. The masa is transported along the conveyors and is automatically diverted into one masa hopper by a diverter gate operated by a controller that receives a signal from a sensor sensing a masa level within an associated one of the hoppers. The hopper has one or more rotating shafts having projections to remove gas bubbles from the masa and force it toward the sheeter rollers. A pair of primary rollers with scrapers can be provided within the hopper to roll the masa to an intermediate thickness before it passes between the sheeter rollers.

Description

adetector deflector plate 41 guides the masa logs 74 onto the horizontal portion 38 of the “L” shaped separator conveyor 24. The masa logs 74 then moves towards the selectively operable diverter gates 42. The photo-sensor 106 mounted adjacent to each masa hopper 40 senses the level of masa 74 therein. If the level of the masa 74 within any one masa hopper 40 drops below a predetermined level, the sensor 106 associated with that mass hopper 40 changes the state of its signal which is sent to the PLC 104. The PLC 104 then commands the pneumatic cylinder 102 to provide the diverter gate 42 located above that masa hopper 40. That diverter gate 42 pivots into an open gap position and the masa logs 74 then fall into that the intermediate masa hopper 40. The photo-sensor 106 then signals the PLC 104 when the level of masa 74 within that mess hopper 40 rises above a certain predetermined level. The PLC 104 then commands the pneumatic cylinder 102 to extend, thereby closing that diverter gate 42 and allowing the masa logs 74 to travel on the next masa hopper 40 48.

An advantage associated with the diverter gates 42 is the corresponding labor savings due to their automatic operation. Normally, human attendants would be necessary to ensure that the masa hoppers 40 each had a proper supply of masa 74. By utilizing the photo-sensors 106, the PLC 104, and the pneumatic cylinders 102, the diverter gates 42 operate automatically and supply of masa logs 74 within each masa hopper 40 is maintained without costly human labor. It should be understood that, while a PLC 104 is preferably used to control the diverter gates 42, a corresponding logic system having electronic relays could also be used to perform the same control functions as the PLC 104. Once the masa logs 74 have been fed to the apparatus masa hopper 40, they must be compressed to remove gas bubbles which cause voids in the rolled masa (not shown).

The self feeding masa hopper 40 compresses and removes the unwanted gas bubbles from the masa 74. The masa is fed, via gravity, to the rotating shafts 52. The projections 122 on the rotating shafts 52 compress the masa 74 and force it through the slot 116 towards the primary rollers 54. The projections 122 on the rotating shafts 52 advantageously remove gas bubbles by compressing the masa 74 without requiring any human labor. Accordingly, the costs associated with the human attendants required by the prior art masa hoppers are avoided. Once the gas bubbles are removed from the masa 74, the masa must be rolled into a generally uniform curtain (not shown).

The primary rollers 54 compress the masa 74 into the generally uniform curtain suitable for feeding to the sheeter rollers 56. Both primary rollers 54 are driven by the masa hopper A/C motor 148 and have different sized drive gears 120 so the primary rollers 54 rotate at different speeds. This arrangement is especially advantageous because, as compared to rollers driven at the same speed, the masa 74 is less likely to stick to the lower surface of the primary rollers 54 when they rotate at different speeds. If the masa 74 sticks to the lower surface 136 of one of the primary rollers 54, it is carried around and will not be fed into the sheeter rollers 56. Accordingly, it is desirable to prevent the masa 74 from becoming stuck to the lower surface of the primary rollers 54. However, if, despite the differential speed, the masa 74 becomes stuck to one of the lower surfaces 136 of the primary toilers 54, it must be removed.

The scrapers 130 will advantageously separate the masa curtain if it becomes stuck to the lower surface 136 of one of the primary rollers 54. The springs 144 bias the blades 132 so that they ride on the lower surfaces 136 of the primary rollers 54. Accordingly, when the masa curtain becomes stuck to the lower surface 136 of one of the primary rollers 54, the blade 233 scrapes it off and is continues to travel towards the sheeter rollers 56.

The sheeter rollers 56 counter rotate at the same speed and compress the masa into its final thickness. The rotary cutter (not shown) cuts circular tortillas 60 from the masa on the underside of one of the sheeter rollers 56. The tortillas 60 then fall onto the tortilla conveyor 58 and are moved towards other feeding processing equipment, such as an oven.

It should be appreciated from the foregoing description that the present invention provides a masa handling system 10 having the following features: the safe separation of the masa stream 20 into individual logs 74; the automatic distribution of those logs 74 to the masa hoppers 40 requiring resupply; the automatic removal of gas bubbles from the masa within the masa hoppers; and the prevention of the masa curtain from becoming stuck to the primary rollers 54.

While a particular form of the invention has been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is not intended than the invention be limited, except as by the appended claims.

Claims

1. A method for handling masa with a food processing system having a pair of aligned, opposed separator conveyors having facing surfaces, the longitudinal ends of the separator conveyors positioned adjacent to a nozzle connected to a masa producing device, the food processing system further having at least two masa hoppers, the masa hoppers and the separator conveyors connected by at least two endless belt feed conveyors having upper surfaces moving in the same direction, the feed conveyors positioned in an upstream and downstream relationship relative to each other, at least one feed conveyor positioned adjacent to the other longitudinal ends of the separator conveyors, each masa hopper having an associated sensor for sensing, the level of the mass and an opening positioned below a diverter gate located between the feed conveyors, each diverter gate connected to an associated mechanism and pivotable between an open position, where the masa is guided from the upstream feed conveyor to the downstream conveyor, and a closed position, where the masa is guided into the masa hopper, each masa hopper located adjacent to a pair of aligned, opposed sheeter rollers, the sheeter rollers located adjacent to a masa hopper having side walls and a bottom wall defining a slot, the masa hopper also having at least one shaft above the bottom wall, each shaft having projections, the method comprising the steps of:

moving the facing surfaces of the separator conveyors at equal speed away from the nozzle;

feeding a generally continuous masa stream through the nozzle such that the masa stream contacts at least one of the facing surfaces of the separator conveyors and is guided between the facing surfaces of the separator conveyors;

gripping the masa stream between the facing surfaces of the separator conveyors pulling the masa stream such that the masa stream is separated into masa logs;

feeding the masa logs onto the upstream end of a feed conveyor; moving the masa logs from the separator conveyors along the upper surfaces of the feed conveyors;

sensing the level of masa within an associated masa hopper;

causing a signal to change its state when the level of masa within the masa hopper is below a predetermined level;

selectively opening and closing the diverter gate to control the flow of masa logs to the masa hopper in response to said change in signal;

placing the masa logs through the opening of one of the masa hoppers;

feeding the masa logs to at least one shaft within the masa hopper; rotating the shaft;

removing gas bubbles from the masa with the projections on at least one shaft; and

forcing the masa through the slot, toward the sheeter rollers, with the projections on at least one shaft.

2. The method as defined by claim 1, wherein the method further comprises the steps of;

arranging the facing surfaces of the separator conveyors to curve toward each other such that a cradle is formed to securely grip the masa.

3. The method as defined by claim 1, wherein the method further comprise the steps of;

adjusting the speed of the facing surfaces of the separator conveyors to change the length of the masa logs.

4. The method as defined by claim 1, wherein the mechanism is a pneumatic cylinder connected to a controller, the method further comprising;

programming the controller to compare said signal to a predetermined value,

selectively commanding the operation of the pneumatic cylinder to control said selective opening and closing of the diverter gate.

5. The method as defined by claim 1, wherein said feeding is accomplished by gravity.

6. The method as defined by claim 1, wherein said rotating is accomplished by an A/C motor.

7. The method as defined by claim 1, wherein the masa hopper also has a pair of opposed, horizontally, aligned primary rollers between the slot and the sheeter rollers, the primary rollers each having a generally cylindrical surface and two ends, the method further comprising the steps of;

rotating the primary rollers;

drawing the masa between the primary rollers;

compressing the masa into a generally uniform curtain; and

feeding said uniform curtain into the sheeter rollers.

8. The method as defined by claim 7, wherein the masa hopper also has two endcaps, each endcap mounted around the ends of the primary rollers, the method further comprising the steps of;

preventing the generally horizontal movement of the masa past the ends of the primary rollers.

9. The method as defined by claim 7, wherein there is a scrapper for each primary roller, each scrapper having a blade pivotally mounted and biased to longitudinally ride on the lower surface of its associated primary roller, the method further comprising the step of:

separating masa from the lower surface of each of the primary rollers.

10. A method for separating a stream of masa utilizing a pair of aligned, opposed separator conveyors having facing surfaces, the longitudinal ends of the separator conveyors positioned adjacent to a nozzle connected to a masa producing device, the method of separating the masa stream comprising the steps of:

moving the facing surfaces of the separator conveyors at equal speed away from the nozzle;

feeding a generally continuous masa stream through the nozzle such that the masa contacts at least one of the facing surfaces of the separator conveyors and is guided between the facing surfaces of the separator conveyors; and

gripping the masa stream between both the facing surfaces of the separator conveyors, pulling the masa stream such that the masa stream is separated into masa logs.

11. The method as defined by claim 10, wherein the method further comprises the steps of:

arranging the facing surfaces of the separator conveyors to curve toward each other such that a cradle is formed to securely grip the masa.

12. The method as defined by claim 11, wherein the method further comprises the step of:

adjusting the speed of the facing surfaces of the separator conveyors to change the length of the masa logs.

13. A method of feeding masa to masa hopper within a food processing system, the food processing system further having a masa producing device and at least two masa hoppers, the masa hoppers and the masa producing device connected by at least two endless belt feed conveyors having upper surfaces moving in the same direction, the feed conveyors positioned in an upstream and downstream relationship relative to each other, each masa hopper having an associated sensor for sensing the level of masa and an opening positioned below a diverter gate positioned between the feed conveyors, each diverter gate connected to an associated mechanism and pivotable between an open position, where the masa is guided from the upstream feed conveyor to the downstream conveyor, and a closed position, where the masa is guided into the masa hopper, the method comprising the steps of:

moving masa logs, previously separated from a stream of masa produced from the masa producing device, along the upper surfaces of the feed conveyors;

sensing the level of masa within an associated masa hopper;

causing a signal to change its state when the level of masa within the masa hopper is below a predetermined level; and

selectively opening and closing the diverter gate to control the flow of masa logs to the masa hopper in response to said change in signal.

14. The method of feeding masa as defined in claim 13, wherein the mechanism is a pneumatic cylinder connected to a controller, the method further comprising the steps of:

programming the controller to compare said signal to a predetermined value; and

selectively commanding the operation of the pneumatic cylinder to control said selective opening and closing of the diverter gate.

15. A method for feeding masa to a pair of aligned, opposed sheeter rollers, the sheeter rollers located adjacent to a masa hopper having an opening for receiving masa and side walls and a bottom wall defining a slot, the masa hopper also having at least one shaft above the bottom wall, each shaft having projections, the method comprising the steps of:

placing the masa through the opening in the masa hopper;

feeding the masa to at least one shaft;

rotating the shaft;

removing gas bubbles from the masa with the projections on at least one shaft; and

forcing the masa through the slot, toward the sheeter rollers, with the projections on at least one shaft.

16. The method for feeding masa as defined in claim 15, wherein said feeding is accomplished by gravity.

17. The method for feeding masa as defined in claim 15, wherein said rotating is accomplished by a motor.

18. The method for feeding masa as defined in claim 17, wherein there is a scrapper for each primary roller, each scrapper having a blade pivotally mounted and biased to longitudinally ride on the lower surface of its associated primary roller, the method further comprising the steps of:

separating masa from the lower surface of each of the primary rollers.

19. The method for feeding masa as defined in claim 15, wherein the masa hopper also has a pair of opposed, horizontally, aligned primary rollers between the slot and the sheeter rollers, the primary rollers each having a generally cylindrical surface and two ends, the method further comprising the steps of:

rotating the primary rollers;

drawing the masa between the primary rollers;

compressing the masa into a generally uniform curtain; and

feeding said uniform curtain into the sheeter rollers.

20. The method for feeding masa as defined in claim 19, wherein the masa hopper also has two endcaps, each endcap mounted around the ends of the primary rollers, the method further comprising the step of:

preventing the movement of the masa past the ends of the primary rollers.

21. A method for feeding masa to a pair of aligned, opposed sheeter rollers, the sheeter rollers located adjacent to a masa hopper having an opening for receiving masa and a slot for dispensing masa, the masa hopper also having at least one shaft above the slot, each shaft having a projection, the method comprising the steps of:

placing the masa through the opening in the masa hopper;

feeding the masa to at least one shaft; and

forcing the masa through the slot, toward the sheeter rollers, with the projection on at least one shaft.

22. The method for feeding masa defined in claim 21 comprising the further step of:

removing gas bubbles from the masa with the projection on at least one shaft.

23. The method for feeding masa as defined in claim 21, wherein said feeding is accomplished by gravity.

24. The method for feeding masa as defined in claim 21, wherein said rotating is accomplished by a motor.

25. The method for feeding masa as defined in claim 21, wherein the masa hopper also ha a pair of opposed, horizontally, aligned primary rollers between the slot and the sheeter rollers, the primary rollers each having a generally cylindrical surface and two ends, the method further comprising the steps of:

rotating the primary rollers;

drawing the masa between the primary rollers;

compressing the masa into a generally uniform curtain; and

feeding said uniform curtain into the sheeter rollers.

26. The method for feeding masa defined in claim 25, wherein there is a scraper for each primary roller, each scraper having a blade pivotally mounted and biased to longitudinally ride on the lower surface of its associated primary roller, the method further comprising the step of:

separating masa from the lower surface of each of the primary rollers.

27. The method for feeding masa as defined in claim 25, wherein the masa hopper also has two endcaps, each endcap mounted around the ends of the primary rollers, the method further comprising the step of:

preventing the movement of the masa past the ends of the primary rollers.

28. A method for feeding masa to a pair of aligned, opposed sheeter rollers, the sheeter rollers located adjacent to a masa hopper having an opening for receiving masa, walls, and a bottom wall defining a slot, the masa hopper also having at least one shaft above the slot, each shaft having a projection, the method comprising the steps of:

placing the masa through the opening in the masa hopper;

feeding the masa to at least one shaft; and

removing gas bubbles from the masa with the projection on at least one shaft.

29. The method for feeding masa defined in claim 28 comprising the further step of:

forcing the masa through the slot, toward the sheeter rollers, with the projection on at least one shaft.

30. The method for feeding masa as defined in claim 28, wherein said feeding is accomplished by gravity.

31. The method for feeding masa as defined in claim 28, wherein said removing is accomplished by rotating the shaft with a motor.

32. The method for feeding masa as defined in claim 28, wherein the masa hopper also has a pair of opposed, horizontally, aligned primary rollers between the slot and the sheeter rollers, the primary rollers each having a generally cylindrical surface and two ends, the method further comprising the steps of:

rotating the primary rollers;

drawing the masa between the primary rollers;

compressing the masa into a generally uniform curtain; and

feeding said uniform curtain into the sheeter rollers.

33. The method for feeding masa defined in claim 32, wherein there is a scraper for each primary roller, each scraper having a blade pivotally mounted and biased to longitudinally ride on the lower surface of its associated primary roller, the method further comprising the step of:

separating masa from the lower surface of each of the primary rollers.

34. The method for feeding masa as defined in claim 32, wherein the masa hopper also has two endcaps, each endcap mounted around the ends of the primary rollers, the method further comprising the step of:

preventing the movement of the masa past the ends of the primary rollers.

35. A method for feeding masa to a pair of aligned, opposed sheeter rollers, the sheeter rollers located adjacent to a masa hopper having an opening for receiving masa, walls, and a bottom wall defining a slot, the masa hopper also having at least one shaft above the slot, each shaft having a projection, the method comprising the steps of:

placing the masa through the opening in the masa hopper;

feeding the masa to at least one shaft;

removing gas bubbles from the masa with the projection on at least one shaft; and

forcing the masa through the slot, toward the sheeter rollers, with the projection on at least one shaft.

36. The method for feeding masa as defined in claim 35, wherein said feeding is accomplished by gravity.

37. The method for feeding masa as defined in claim 35, wherein said rotating is accomplished by a motor.

38. The method for feeding masa as defined in claim 35, wherein the masa hopper also has a pair of opposed, horizontally, aligned primary rollers between the slot and the sheeter rollers, the primary rollers each having a generally cylindrical surface and two ends, the method further comprising the steps of:

rotating the primary rollers;

drawing the masa between the primary rollers;

compressing the masa into a generally uniform curtain; and

feeding said uniform curtain into the sheeter rollers.

39. The method for feeding masa as defined in claim 38, wherein there is a scraper for each primary roller, each scraper having a blade pivotally mounted and biased to longitudinally ride on the lower surface of its associated primary roller, the method further comprising the step of:

separating masa from the lower surface of each of the primary rollers.

40. The method for feeding masa as defined in claim 38, wherein the masa hopper also has two endcaps, each endcap mounted around the ends of the primary rollers, the method further comprising the step of:

preventing the movement of the masa past the ends of the primary rollers.

41. A method for feeding masa to a pair of aligned, opposed sheeter rollers, the sheeter rollers located adjacent to a masa hopper for receiving masa and an opening at a bottom end of the hopper for dispensing masa, the masa hopper also having at least one shaft above the opening, each shaft having a projection, the method comprising the steps of:

placing the masa into the masa hopper;

feeding the masa to at least one shaft; and

moving the masa out of the opening of the hopper, toward the sheeter rollers, with the projection on at least one shaft.

42. The method for feeding masa as defined in claim 41, wherein said feeding is accomplished by gravity.

43. The method for feeding masa as defined in claim 41, wherein said moving is accomplished by rotating the shaft with a motor.

44. The method for feeding masa as defined in claim 41, wherein the masa hopper also has a pair of opposed, horizontally aligned, primary rollers between the opening and the sheeter rollers, the primary rollers each having a generally cylindrical surface and two ends, the method further comprising the steps of:

rotating the primary rollers;

drawing the masa between the primary rollers;

compressing the masa into a generally uniform curtain; and

feeding said uniform curtain into the sheeter rollers.

45. The method for feeding masa defined in claim 44, wherein there is a scraper for each primary roller, each scraper having a blade pivotally mounted and biased to longitudinally ride on the lower surface of its associated primary roller, the method further comprising the step of:

separating masa from the lower surface of each of the primary rollers.

46. The method for feeding masa as defined in claim 44, wherein the masa hopper also has two endcaps, each endcap mounted around the ends of the primary rollers, the method further comprising the step of:

preventing movement of the masa past the ends of the primary rollers.