WO1999062648A1 - Automatic loader for food processing machines - Google Patents

Abstract

A tiltable tray (20) is loaded, either manually or automatically, with food products. When signalled by a central computer (19) of the need for a food product, such as a food log, in a cluster box of a food slicing machine (30), the tray is moved linearly to the edge of the cluster box's top openings (32, 34, 36, 38). The tray is then tilted to drop the food log into the cluster box, permitting food to be continuously sliced. The tray is preferably loaded by an automatic loader having a lower horizontal conveyor (52), a vertical conveyor (54), and an upper horizontal conveyor (80). The vertical conveyor has paddles (68) that pick up food logs from the lower horizontal conveyor and drop them onto the upper horizontal conveyor. The food logs are then dropped into the tray by the upper horizontal conveyor when the tray is empty.

Description

TITLE OF THE INVENTION: AUTOMATIC LOADER FOR FOOD

PROCESSING MACHINES

CROSS-REFERENCES TO RELATED APPLICATIONS This application claims the benefits of U.S. Provisional Application No. 60/088,299 filed June 5, 1998.

BACKGROUND OF THE INVENTION

Field Of The Invention

This invention relates generally to food processing machines, and more particularly to an apparatus for automatically loading food products into food processing machines.

Description Of The Related Art Conventional food processing machines slice or otherwise process food products placed in a workpiece retaining carriage. For example, food log slicing machines have a vertically aligned tube receptacle, called a cluster box, which retains an elongated food log while the food log is sliced.

The lower end of a conventional cluster box reciprocates along an arcuate or linear path, and the lower end of the food log protrudes therefrom and is reciprocated against a blade to form a slice of the log in a conventional manner. As the log is sliced, it becomes shorter, and eventually an additional food log must be added to the cluster box in order to continue producing slices after the first food log is gone. Conventionally, human workers insert food logs into the cluster boxes as needed, but sometimes the need for a food log goes unnoticed for too long.

Additionally, the slices formed are affected to some extent by the weight pressing down upon the portion of the food log that is being sliced. The weight affects the density of the sliced portion, which can affect the slice thickness due to compressibility of some food products. Too much variation in weight on the sliced portion can produce an inconsistent slice thickness, and it is therefore desirable to maintain the weight upon the sliced portion within an acceptable range. Control and consistency in the maintenance of food logs within the cluster boxes is desired, and therefore an apparatus which exerts such control is desirable.

SUMMARY OF THE INVENTION

The invention is an automatic loading mechanism for a top-loaded food processing machine, preferably a reciprocatable food slicing machine. The loading mechanism includes, broadly, a tiltable tray. The tray is designed to hold an elongated food product, such as a log of processed meat or a stick of butter, but can also hold other shapes, such as spherical or irregularly shaped workpieces .

Upon reaching the opening into which the log is desired to be placed, the tray is tilted upwardly at the outboard end and drops the inboard end of the log down into a conventional reciprocating cluster box. After the tray has emptied its contents into the assigned cluster box, it returns to a home position, and in a preferred embodiment it is refilled by an elevating conveyer.

The machine which the invention loads could, alternatively, distribute shredded food, such as cheese or some other product, from its lower end. In the preferred embodiment, the cluster box, blade and reciprocating mechanism comprise the slicing machine shown in U.S. Patent Number 4,436,012, or alternatively, the machines shown in U.S. Patent Numbers 4,543,864, 4,230,007, 3,760,715 or 4,145,990, all of which are incorporated by reference, or machines which perform similar functions .

BRIEF DESCRIPTION OF THE DRAWINGS The invention operates with reference to the following drawings:

Fig. 1 is a top view illustrating the tray and carrier, and the drive mechanism;

Fig. 2 is an end view illustrating the tray and carrier mounted to an exemplary conventional slicing machine;

Fig. 3 is a side view illustrating the preferred embodiment of the present invention mounted to an exemplary conventional slicing machine ;

Fig. 4 is an end view illustrating the apparatus shown in Fig . 3 ; and Fig. 5 is a side view illustrating the preferred scale conveyor.

In describing the preferred embodiment of the invention which is illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific terms so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. For example, the word connected or terms similar thereto are often used. They are not limited to direct connection but include connection through other elements where such connection is recognized as being equivalent by those skilled in the art.

BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENT Fig. 1 shows a pair of low friction plastic bushings 12 and 14 mounted to the linearly drivable carrier 10. The bushings 12 and 14 slidably engage a pair of parallel guide rails 16 and 18. One of the bushings is rigidly mounted to the carrier 10, and the other is slidably and pivotably mounted to the carrier 10 to accommodate any small misalignment between the guide rails 16 and 18. The tiltable tray 20 is pivotably mounted to the carrier 10, although the tray 20 and carrier 10 could be one piece. When the carrier 10 is driven along the rails 16 and 18 the tray 20 stays in the same linear position relative to the carrier 10.

Linear driving of the carrier 10 is accomplished by a linear actuator including a servo mechanism. An endless loop, toothed belt 22 extends from a gear 25 connected to a drive motor, preferably the servo motor 24, to the carrier 10 and the idler gear 26 to drive the carrier 10 linearly along the guide rails 16 and 18 to predetermined positions. The predetermined positions along the guide rails correspond to the top openings of cluster boxes 32, 34, 36 and 38 in the slicing machine 30, but could correspond to any position selected by the user. Once driven to the predetermined position, the attached tray 20 is tilted to discharge its cargo into the cluster box at the predetermined position. The predetermined positions are preferably programmed into a central computer 19, or, alternatively, sensors can be mounted to the carrier 10 to sense indicators at the location at which the tray 20 should be tilted. The tray 20 is tilted by rotating a square shaft 40 which extends perpendicularly and slidably through a square aperture at the inboard end of the tray 20. The shaft 40 could, of course, be any polygonal shape. The square shaft 40 is parallel to the guide rails 16 and 18, mounting to a bearing 42 at one shaft end and a rotary actuator 41 near the opposite shaft end. The rotary actuator 41, shown in Figs. 1 and 2, rotates the shaft 40 approximately 90 degrees, tilting the tray 20 from its rest (horizontal) position to its unload (vertical) position. The preferred rotary actuator 41 is a rack type, but could alternatively be a paddle type if the torque generated is sufficient.

A conventional encoder (not shown) is mounted near the end of the shaft 40 to detect the position of the shaft 40 at all times. As the shaft 40 is being rotated, the encoder transmits the shaft's angular position to the central computer 19. The rotary actuator is controlled by the central computer 19 to rotate the shaft 40 in one direction to raise the tray 20, halt the rotation or rotate the shaft 40 in the opposite direction to lower the tray 20, whichever the central computer signals the rotary actuator to do. The encoder, the rotary actuator 41 and the central computer 19 comprise a feedback control system, which could be substituted by any suitable conventional feedback control system.

In the embodiment shown in Fig. 1, the slicing machine has four cluster boxes 32-38, each of which can hold a food product workpiece, such as a log of meat, cheese, etc. The cluster boxes 32-38 are part of a workpiece-retaining carriage that moves the lower end of the workpiece through a blade for forming slices.

At the top end of each cluster box 32-38, which is shown more clearly in Fig. 2, is a hopper 33, 35, 37 and 39, which directs replacement logs into correct alignment in the cluster box. After the carrier 10 and tray 20 are conveyed to a predetermined position corresponding to a cluster box, the tray 20 is tilted upwardly by rotation of the shaft 40, and the inboard end of the log drops downwardly into the cluster box under the force of gravity. Any misalignment between the log and the cluster box opening is corrected by the wide opening of the hopper, which guides the lower end of the log downwardly into the top opening of the cluster box.

The need in a particular cluster box for another food log is sensed by receptacle sensors 42, 44, 46 and 48 (see Fig. 3) . Preferably one sensor is mounted at each cluster box 32-38. The preferred type of sensor for the receptacle sensors 42-48 is a photovoltaic cell, positioned with its detecting surface facing into the interior of the cluster box through a hole formed through the cluster box sidewall. An aligned hole (not shown) formed on the opposite sidewall of the cluster box permits a greater amount of light to strike the photovoltaic sensor when a food log has passed below the sensor. The sensor's signal to the central computer indicates that the upper end of the food log has dropped below the sensor, and therefore a food log is needed in that cluster box. The invention operates as follows: the cluster boxes 32-38 are continuously operating in a cyclical manner to cut slices off of the food logs, thereby causing the upper ends of the food logs to descend slightly lower into the cluster boxes with every slice cut. When an upper end of a food log drops below a receptacle sensor 42-48, the central computer receives a signal from the sensor that causes the central computer to actuate the servo motor 24 to linearly displace the tray 20 and carrier 10 to the hopper that feeds the cluster box in need of another food log.

Once the carrier 10 and tray 20 are positioned at the upper end of the desired cluster box, the central computer, which tracks the position of the carrier 10 at all times, causes the rotary actuator 41 to rotate the shaft 40. This rotation of the shaft 40 causes the sides of the square shaft 40 to abut the sides defining the square aperture on the tray 20 through which the shaft 40 extends. Further rotation of the shaft 40 tilts the tray's outboard end upwardly about the axis of the shaft 40 until the tray 20 is approximately vertical for a short time period. The position of the tray is directly related to the position of the shaft 40, the position of which is communicated to the central computer by the encoder. Tilting of the tray 20 approximately 90 degrees from its horizontal, rest position (as detected by the encoder) causes the food log to drop into the cluster box when the force of gravity overcomes frictional forces retaining the food log in the tray.

After the tray 20 dwells in the vertical position a predetermined time period, the central computer causes the rotary actuator 41 to tilt the tray 20 back down to its approximately horizontal rest position. As the tray 20 is dropping back to its rest position, the carrier 10 and tray 20 are driven along the guide rails 16 and 18 back toward the home position. The tilted position of the tray 20 is constantly monitored by the central computer, as communicated to the central computer by the encoder near the end of the shaft 40. The position of the carrier 10 is also constantly monitored by the central computer, as communicated to the central computer by the servo mechanism. If the tray 20 has not pivoted back to its horizontal position as it and the carrier 10 approach the home position, the central computer will slow the movement of the carrier 10 and tray 20 by controlling the servo mechanism. This avoids contact between the tray 20 and the preferred tray-loading mechanism shown in Figs . 3 and 4.

In the preferred embodiment, the tray 20 is loaded with a food log as soon as it returns to its home position. This can be manually performed by a person standing near the tray's home position, or, more preferably, by the elevating conveyor 50 shown in Figs. 3 and 4. The elevating conveyor 50 has a lower, horizontal conveyor 52 which is manually loaded by hand with a plurality of food logs, and which advances the food logs toward the vertical conveyor 54 as the central computer actuates the lower, horizontal conveyor's conventional drive system to do so. At least one sensor 56, preferably the capacitive cell shown in Fig. 4, is mounted facing just above the top surface of the lower horizontal conveyor 52. When a food log is driven to a predetermined distance from the sensor 56, preferably onto the fixed lip 58 shown in Fig. 3, the sensor 56 signals the central computer, which halts the drive mechanism of the lower horizontal conveyor 52.

The vertical conveyor 54 conveys the food logs from the fixed lip 58 to an upper horizontal conveyor 80. The vertical conveyor 54 comprises an endless loop chain 60 that is driven by a servo motor drive mechanism 62 that is controlled by the central computer 19. A plurality of platform pairs 66 with radial paddles 68 are mounted to the chain 60 at spaced intervals. The chain 60 is advanced by the drive mechanism 62, and as the chain 60 is driven, the platform pairs that are proceeding upwardly ride in tracks 61 and 63 to prevent dipping of the paddles due to chain slack that might otherwise cause food logs to be dropped prematurely.

Preferably, one platform pair's paddles align flush with, or slightly below, the upper surface of the lip 58 when the chain 60 stops. The central computer subsequently signals the lower horizontal conveyor's drive mechanism to drive a food log beyond the edge of the lower horizontal conveyor 52, causing it to fall onto the lip 58. When a food log is detected by the sensor 56, on the lip 58, the paddles, which are registered just below the upper surface of the lip 58, are subsequently driven through openings provided in the lip 58 to lift the food log off of the lip 58 when the drive mechanism 62 of the vertical conveyor 54 is actuated by the central computer. This drives the paddles upwardly until the next pair of paddles registers with the lip 58. Once this registration occurs, the vertical conveyor 54 is halted and the lower horizontal conveyor advances a food log onto the lip 58. Thus, each upwardly proceeding platform on the vertical conveyor 54 has a food log on its paddle . A sensor 78 is positioned to detect the position of each platform's paddle, although a servo mechanism could, alternatively, track the paddles' positions, providing the central computer with data that can be used to keep track of the position of each platform.

Each vertically lifted food log is conveyed in sequence onto the upper horizontal conveyor 80. The upper horizontal conveyor 80 is drivingly linked to the same drive mechanism 62 that drives the vertical conveyor 54. Therefore, the upper horizontal conveyor 80 preferably advances horizontally at the same speed that the vertical conveyor 54 advances vertically, and both conveyors 54 and 80 do so whenever the drive mechanism 62 is operating. When a food log reaches the peak of the vertical conveyor 54, it is carried over the vertical conveyor by the paddle pair and dropped onto the upper horizontal conveyor 80. The upper horizontal conveyor 80 transports the food log away from the still-moving paddles, which pass through openings between the conveyor belts of the upper horizontal conveyor 80. Once it is supported by the upper horizontal conveyor, the food log travels horizontally away from the vertical conveyor 54 at the same speed that the vertical conveyor 54 drives the paddles. Therefore, contact between the paddles and food log is negligible or nonexistent. The rounded edges of the paddles may contact the sides of the food log to further propel it away from the paddles if desired. Once the food log is on the moving upper horizontal conveyor 80, it is transported toward an outer edge until the sensor 82 (see Fig. 3) detects its presence. The sensor 82 signals the central computer as to the presence of the food log, and the central computer stops the upper horizontal conveyor 80 by stopping the drive mechanism 62. This leaves a food log, for example the food log 84, on the edge of the upper horizontal conveyor. Preferably, food logs will also be on each of the paddle pairs of the vertical conveyor (assuming the lower horizontal conveyor has enough food logs to fill these paddle pairs) . All of these food logs stay in place until the tray 20 can accept one of them. When the tray 20 is emptied and returns to its home position, a second sensor 83 (see Fig. 3) on the vertical conveyor detects that no food log is present in the tray 20 and signals the central computer accordingly. The central computer actuates the drive mechanism 62 to drive the upper horizontal conveyor 80, thereby depositing the food log 84 into the tray 20. The actuation of the drive mechanism 62 drives the vertical conveyor 54, thereby picking up another food log from the lip 58 and placing another on the upper horizontal conveyor 80.

The filling and unloading of the tray 20 and the advancing of the upper horizontal conveyor 80, the vertical conveyor 54 and the lower horizontal conveyor 52 are all controlled by the central computer to maintain the height of food logs in the cluster boxes within a predetermined range. The central computer actuates the drive systems to keep the food logs that are manually placed upon the lower horizontal conveyor 52 advancing into the slicing machine 30 to produce consistent slices. Therefore, all that is necessary to keep four cluster boxes as full as necessary to slice food products is a person who manually loads the food logs onto the lower horizontal conveyor 52. Each slice formed by the slicing machine 30 must be removed eventually from the machine 30. The removal can be performed by a conventional horizontal conveyor or similar device, but is preferably performed by the conveying scale 90 shown in Fig. 5. The conveying scale 90 is positioned beneath the cluster boxes 32-38 to receive the downwardly falling, just-formed slices of food. Of course, the food slices could be dropped onto any conventional stacking or interleaving mechanism prior to being placed on the conveyor.

The horizontally driven belt 92 of the conveying scale 90 receives slices of food product from the cluster boxes, transports them to the far edge 94, and drops them into a hopper 95, which feeds the slices into a container 96 on the scale 98. Because the conveying scale 90 is connected to the central computer, the weight data of the slices in the container 96 can be sent to the computer, which stops the driven belt 92 when the container's weight reaches a predetermined amount in order to prevent additional slices from being added to a filled container 96. A human-perceptible signal, such as a bell or buzzer, is emitted to indicate to the operator of the machine to remove the filled container 96 and replace it with an empty container. A switch (not shown) is then depressed by hand, signaling the central computer that the conveying scale has an empty container and can receive more slices. The driven belt 92 is then actuated by the central computer to again begin dropping slices into the container.

While the driven belt 92 is stopped so that no slices drop into the container, the slicing machine 30 can continue dropping slices onto the driven belt 92. The number of slices that can be dropped onto the driven belt 92 while it is stopped is determined according to variables such as slice thickness, food type, clearance between the conveyor and the slicing machine, etc. For example, it may be that the slicing machine can complete 6 strokes while the conveyor is not moving, which will afford the operator about 6 seconds (on conventional slicing machines at 60 strokes per minute) to remove the filled container, replace it with an empty container and depress the switch to reactivate the system. This permits an average person to operate the entire machine, by loading it with food logs on the lower horizontal conveyor 52 and removing the full container 96 of slices. The machine shown is designed to load, slice and transport butter into containers. However, it also can, after slight modifications to accommodate different shapes and sizes, perform the same function on meats, cheeses, vegetables, other foods and processed logs and other workpieces . Furthermore, the central computer is programmed to effectively carry out the efficient processing of loaded food logs. This includes such features as halting the machines described when no food logs are present (and possibly before if certain conditions exist) , and preventing operation of any machine if less than all safety precautions, such as housing guards, are in place, etc. Of course, anyone familiar with related technology could imagine an unlimited number of circumstances in which certain machine operations should be prescribed or proscribed, and the central computer programmed accordingly. Such variations will be obvious from the present description.

While certain preferred embodiments of the present invention have been disclosed in detail, it is to be understood that various modifications may be adopted without departing from the spirit of the invention or scope of the following claims.

Claims

1. An automatic loader for a food processing machine having a food product workpiece-retaining receptacle that receives a food product workpiece near a top receptacle end, the automatic loader comprising:

(a) a tiltable tray mounted adjacent the food processing machine with a first tray end closer to the receptacle than an opposite, second tray end, said tray having an upper, workpiece-supporting surface; and

(b) a rotary actuator drivingly linked to the tray for rotating the tray into a tilted position in which the first tray end is below the second, opposite tray end, wherein a food product workpiece supported on the upper tray surface is dropped into the receptacle.

2. An automatic loader in accordance with claim 1, further comprising: (a) a receptacle sensor mounted to the receptacle for detecting a workpiece in the receptacle; and

(b) a processor connected to the receptacle sensor and the rotary actuator for signaling the rotary actuator to tilt the tray if the workpiece in the receptacle falls below a predetermined height.

3. An automatic loader in accordance with claim 2, further comprising a linear actuator drivingly linked to the tray for driving the tray between a tray home position and a receptacle-filling position in which the first tray end is directly adjacent the upper end of the receptacle.

4. An automatic loader in accordance with claim 3, further comprising multiple, spaced, receptacle- filling positions corresponding to second, third and fourth food product workpiece-retaining receptacles.

5. An automatic loader in accordance with claim 3, further comprising: (a) an upper, substantially horizontal conveyor mounted above the tray home position;

(b) a lower, substantially horizontal conveyor mounted below the upper horizontal conveyor; and

(c) a substantially vertical conveyor mounted between the upper horizontal conveyor and the lower horizontal conveyor, the vertical conveyor having radial paddles mounted to a drivable, closed loop for lifting a food product workpiece from the lower horizontal conveyor to the upper horizontal conveyor.

6. An automatic loader in accordance with claim 5, further comprising:

(a) a first workpiece sensor connected to the processor and mounted near an intersection of the vertical conveyor and the lower horizontal conveyor for detecting a workpiece at said intersection;

(b) a second workpiece sensor connected to the processor and mounted near the upper horizontal conveyor for detecting a workpiece on the upper horizontal conveyor; and

(c) a third workpiece sensor connected to the processor and mounted near the upper surface of the tray for detecting a workpiece on the upper surface of the tray.

7. An automatic loader in accordance with claim 3, wherein the linear actuator comprises:

(a) a rotary motor including a driven gear mounted to a rotary motor driveshaft;

(b) an idler gear mounted on the opposite side of the tray as the rotary motor; and

(c) a toothed belt connected to the tray, extending around the driven gear and the idler gear.

8. An automatic loader in accordance with claim 3 , further comprising a polygonal shaft extending from the rotary actuator near one end to a bearing near the opposite end, said shaft extending slidably through a polygonal aperture formed in the tray.

9. An automatic loader in accordance with claim 8, wherein the tray is supported by a pair of guide rails that are substantially parallel to each other and the polygonal shaft .

10. An automatic loader for a food processing machine having a food product workpiece-retaining receptacle that receives a food product workpiece near a top receptacle end, the automatic loader comprising:

(a) a receptacle sensor mounted to the receptacle for detecting a workpiece in the receptacle;

(b) a tiltable tray mounted adjacent the food processing machine with a first tray end closer to the receptacle than an opposite, second tray end, the tray having an upper, workpiece-supporting surface;

(c) a rotary actuator drivingly linked to the tray for rotating the tray into a tilted position in which the first tray end is below the second, opposite tray end, wherein a food product workpiece supported on the upper tray surface is dropped into the receptacle;

(d) a processor connected to the receptacle sensor and the rotary actuator for signaling the rotary actuator to tilt the tray if a workpiece in the receptacle falls below a predetermined height;

(e) a linear actuator drivingly linked to the tray for driving the tray between a tray home position and a receptacle-filling position in which the first tray end is directly adjacent the upper end of the receptacle;

(f) an upper, substantially horizontal conveyor mounted above the tray home position;

(g) a lower, substantially horizontal conveyor mounted below the upper horizontal conveyor;

(h) a substantially vertical conveyor mounted between the upper horizontal conveyor and the lower horizontal conveyor, the vertical conveyor having radial paddles mounted to a drivable, closed loop for lifting a food product workpiece from the lower horizontal conveyor to the upper horizontal conveyor;

(i) a first workpiece sensor connected to the processor and mounted near an intersection of the vertical conveyor and the lower horizontal conveyor for detecting a workpiece at said intersection;

(j) a second workpiece sensor connected to the processor and mounted near the upper horizontal conveyor for detecting a workpiece on the upper horizontal conveyor; and

(k) a third workpiece sensor connected to the processor and mounted near the upper surface of the tray for detecting a workpiece on the upper surface of the tray.

11. An automatic loader in accordance with claim 10, wherein the linear actuator comprises:

(a) a rotary motor including a driven gear mounted to a rotary motor driveshaft; (b) an idler gear mounted on the opposite side of the tray as the rotary motor; and

(c) a toothed belt connected to the tray, extending around the driven gear and the idler gear.

12. An automatic loader in accordance with claim 10, further comprising a polygonal shaft extending from the rotary actuator near one end to a bearing near the opposite end, said shaft extending slidably through a polygonal aperture in the tray.

13. An automatic loader in accordance with claim 12, wherein the tray is supported by a pair of guide rails that are substantially parallel to each other and the polygonal shaft.