Pump system for food machine

Dual foods pump arrangement that includes a pump manifold, two food pumps, and a rotary valve element removably located within the manifold. The rotary valve element is operated to selectively direct the flow of food product from the two food pumps in alternating fashion through a single manifold outlet. The food pumps are driven by servo actuated cylinders. A tool is provided for lifting the valve element from the manifold that includes a pivotal removal bar that can be attached to a top of the valve element.

BACKGROUND OF THE INVENTION

Food material pumps using overlapping, alternating plungers that pressurize alternating supplies of food material are known.

The FORMAX® F-26™ reciprocating mold plate forming machine has enjoyed widespread commercial success for many years. A typical FORMAX® F-26™ molding machine can operate at 90 strokes per minute and produce about 32,400 patties per hour based on the standard width mold plate for the F-26™ which is about 27 inches wide and can include 6 mold cavities.

The FORMAX® F-26™ molding machine is generally described in U.S. Pat. Nos. 3,887,964; 4,356,595 and 4,996,743. The FORMAX® F-26™ includes a supply system for supplying a moldable food material, such as ground beef, fish, or the like, to the processing mechanisms of the machine. The supply system comprises a large food material storage hopper that opens into the intake of a food pump system. The food pump system includes at least two food pumps that continuously pump food, under pressure, into a manifold connected to a cyclically operable molding mechanism.

In the operation of a FORMAX® F-26™ patty-forming machine, a supply of ground meat or other moldable food material is disposed into the hopper from overhead. The floor of the hopper comprises a conveyor belt for moving the food material longitudinally of the hopper toward the other components of the food material supply system.

At the forward end of the hopper the food material is fed downwardly by the supply system into the intake of the reciprocating pumps constituting the pumping system. The pumps operate in overlapping alteration to each other; at any given time when the machine is in operation at least one of the pumps is forcing food material under pressure into the intake of the manifold.

The manifold comprises a valving system for feeding the food material, still under relatively high pressure, into the molding mechanism. The molding mechanism operates on a cyclic basis, first sliding a multi-cavity mold plate into receiving position over the manifold and then away from the manifold to a discharge position wherein a knock out system removes the molded products from the mold cavity.

The molding mechanism further comprises a knockout system. The knockout system comprises knockout cups, which are affixed to a carrier bar that is removably mounted upon a knockout support member. The knockout cups are coordinated in number and size to the mold cavities in the mold plate; there is one knockout cup aligned with each mold cavity and the mold cavity size is somewhat greater than the size of an individual knockout cup.

Although the FORMAX® F-26™ patty-forming machine includes an integrated overlapping, alternating dual food pumps, the present inventor has recognized the advantages of an improved food pumping system with more flexibility of application that can be incorporated into a food patty molding machine or another food processing machine such as a separator. The present inventor has recognized the need for a pumping system that had a reduced cost of maintenance and a rugged construction.

SUMMARY OF THE INVENTION

A pumping system for a food machine such as a food patty molding machine has two reciprocating food pumps for pumping food product in an alternating fashion. The reciprocating food pumps are located horizontally and adjacent to each other. Each food pump comprises an actuating cylinder connected to a piston rod. The distal end of the piston rod is connected to a plunger. The plunger moves within a pump cavity to receive and push food product into a manifold.

Within the manifold is a valve which alternates between two positions to channel food product from a first pump cavity into the manifold, and to channel food product from a second pump cavity into the manifold. The rotary valve element rotates horizontally between the two positions to receive food product from the food pumps and to channel the food product through the manifold and into a downstream food machine such as into mold cavities. The rotating movement of the rotary valve element is actuated by a linkage system comprising an actuating arm connected to a shaft with which the rotary valve element moves.

The rotary valve element is disposed within the manifold between a fan shaped receiving area which receives food material from each of the pumps, and the manifold outlet. The rotary valve element is supported in position within the manifold by a bottom cover. The top of the rotary valve element is beneath a top cover. Both the bottom and top covers of the rotary valve element are secured to the manifold housing by fastening mechanisms such as screws or bolts.

To remove the rotary valve element from the manifold for cleaning, maintenance, or for other purposes, the top cover is removed to allow the top of the rotary valve element to be accessible. A valve removal tool engages with the top of the pump to form a connection which allows the tool to lift the rotary valve element from its position within the manifold.

Numerous other advantages and features of the present invention will be become readily apparent from the following detailed description of the invention and the embodiments thereof, and from the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The directions “left” side and “right” side of the patty-forming machine are according to the convention shown inFIG. 3.

The General Organization and Operation of the Patty Molding Machine

A high speed food patty molding machine20is illustrated inFIGS. 1 and 2. The FORMAX® F-26™ patty-forming machine is generally described in U.S. Pat. No. 3,887,964 (RE 90,036), U.S. Pat. No. 4,356,595 and U.S. Pat. No. 4,996,743. These patents are herein incorporated by reference to assist in the understanding of the basic operation and configuration of the machine20, except as modified herein.

As shown inFIG. 1, molding machine20includes a machine base21, preferably mounted upon a plurality of rollers or wheels22. Machine base21comprises an external skin21aand an internal frame21band supports the operating mechanism for machine20. The base21comprises a mechanical compartment that contains hydraulic actuating systems, electrical actuating systems, and most of the machine controls.

Molding machine20includes a supply system24for supplying a moldable food material, such as ground beef, fish, or the like, to the processing mechanisms of the machine. As generally illustrated inFIG. 1supply system24comprises a large food material storage hopper25that opens into the intake of a food pump system26. The exterior surface of the storage hopper has a hygienic logo25apermanently etched into stainless steel surface. The food pump system26includes at least two food pumps that continuously pump food, under pressure, into a manifold27connected to a cyclically operable molding mechanism28. Molding mechanism28can be provided with an elevator system for use in changing the molding mechanism from one product to another, as described in detail.

In the operation of machine20, a supply of ground meat or other moldable food material is disposed into hopper25from overhead. The floor of hopper25comprises a conveyor belt31for moving the food material longitudinally toward the other components of the food material supply system24. An elevated mirror25gallows operating personnel to view inside the hopper25.

At the forward end of the hopper25, as seen inFIG. 1, the food material is fed downwardly by the supply system24into the intake of the reciprocating pumps constituting pumping system26. The pumps of system26operate in overlapping alteration to each other; at any given time when machine20is in operation at least one of the pumps is forcing food material under pressure into the intake of manifold27.

The manifold27comprises a valve system for feeding the food material, still under relatively high pressure, into the molding mechanism28. Molding mechanism28operates on a cyclic basis, first sliding a multi-cavity mold plate into receiving position over manifold27and then away from the manifold to a discharge position aligned with a series of knockout cups as described in U.S. Patent Application Publication No. 2008/0233226, herein incorporated by reference.

The food supply system24and associated hopper25are illustrated inFIG. 1. Conveyor belt31extends completely across the bottom of hopper25, around an end roller35and a drive roller36, to convey food towards the forward end of the hopper and the vertical pump feed opening.

The drive roller36can comprise a sealed drum motor. The sealed drum motor is located inside the roller. Such drum rollers are available from ITOH DENKI. The use of a drum motor eliminates the need for chains and sprockets such that the roller could be driven from the machine motor. Furthermore, the use of a drum motor allows the drive to be more effectively sealed since only an electrical connection need be connected.

Feed Screw System

The forward end of hopper25communicates with a vertical pump feed opening39that leads downwardly into a pump intake chamber41. An inverted U-shaped frame42is mounted on machine base21, extending over hopper25.

As shown inFIG. 2, three electric feed screw drives45,46and47are mounted upon a motor mount plate48that is mounted to and above the support plate43by long bolts48aand end walls49a,49b. The plate43includes tapped holes to engage the bolts48a. Bolts50aand sleeves48bextend down from the support plate43to hold a cover or shield48caround and above the feed screws51-53. The feed screw drives45,46,47may be compact, integrated electric motor/gearbox assemblies such as SUMITOMO model #CNVMO5-6100YC.-35, 0.5 horsepower.

Drive45drives a feed screw51that extends downwardly through opening39in alignment with a pump plunger. Drive46drives a centrally located feed screw52, whereas drive47drives a third feed screw53, located at the opposite side of hopper25from screw51and aligned with another pump plunger.

The feed screws51,52,53include heavy wall thickness flights of about 0.25 inches.

The drives45-47are substantially identical and the feed screws51-53are substantially identical.

The feed screw system as illustrated inFIG. 2is enclosed in a one piece stainless steel feed screw drive enclosure57. The support plate43is placed within the enclosure57as part of the assembly. A cover57ais fastened onto the enclosure57.

The feed screw system can comprise two independent level sensing elements54,55extending downwardly from shafts54a,55aas shown in FIG.2. The level sensing elements are pneumatically biased and configured as described in U.S. Pat. No. 7,255,554, herein incorporated by reference.

When machine20is in operation, the feed screw drives45and46are energized whenever plunger is withdrawn, so that feed screws51and52supply food product from hopper25downwardly through opening39and into one side of the intake41of the food pumping system26. Similarly, drives46and47actuate feed screws52and53to feed meat to the other side of intake41whenever plunger is withdrawn. In each instance, the feed screw drives are controlled to shut off shortly after the plunger is fully retracted, avoiding excessive agitation of the meat. As the supply of food material in the outlet39of hopper25is depleted, conveyor belt31continuously moves the food forwardly in the hopper and into position to be engaged by feed screws51-53. If the level of meat at the outlet end39of hopper25becomes excessive, conveyor31is stopped, as described above, until the supply at the hopper outlet is again depleted. The wall of the hopper outlet39immediately below conveyor drive roller36comprises a belt wiper blade57that continuously engages the surface of belt31and prevents leakage of the meat or other food material from the hopper at this point.

The Food Pump System

A new pump system26′ is illustrated inFIGS. 3 to 18. This pump system26′ can be a stand-alone unit that is connected as desired to another downstream food processing machine such as a separator, or incorporated into a forming machine such as the machine20shown inFIGS. 1 and 2.

As shown inFIGS. 3 and 4, pump system26′ comprises two reciprocating food pumps61and62mounted upon the top of machine base21. The first food pump61includes a servo actuated cylinder64. A piston (not shown) in cylinder64is connected to an elongated piston rod67; the distal end of piston rod67is connected to a large plunger68. Plunger68is aligned with a first pump cavity69formed by a pump cavity enclosure71that is divided into two chambers by a central divider wall72. The pump cavity has an outlet which allows food material to flow into a receiving channel73of a manifold27′.

The second food pump62is essentially similar in construction to pump61and comprises a servo actuated cylinder84. Cylinder84has a piston rod87, shown in its retracted position, connected to a large plunger88that is aligned with a second pump cavity89in housing71. The pump cavity has an outlet which allows food material to flow into a receiving channel73aof manifold27′.

FIG. 5illustrates one of the servo actuated cylinders64. Piston rod67is shown in its extended position (“B”), and retracted position (“A”). A motor64adrives the actuating cylinder64. A drive belt64bis coupled to a toothed gear64dof the motor64a, and a toothed gear64dof the actuating cylinder such that rotation of the gear64ccauses the gear64dto rotate in a corresponding rotation to retract or extend the piston rod67.

InFIGS. 3 and 4, the pumping system26′ is illustrated with the first pump61compressing food material to the desired pressure prior to pumping the moldable food material into manifold27′, and with the second pump62ready to receive a supply of the moldable food material for a subsequent pumping operation. The supply can be though an opening89ain the top of the cavity89, such as the vertical pump feed opening39, described above with respect to the embodiments ofFIGS. 1 and 2. A hopper and feed screws for holding and transferring food material down into the pump cavity, such as described above with respect to the embodiments ofFIGS. 1 and 2, can also be associated with the pumping system26′. Alternately, other methods of refilling the pump cavities are incorporated by the invention.

Pump61has begun its pumping stroke, and is compressing the food product in pump cavity69by pressing the food material against the closed valve, in anticipation of forcing the moldable food material into the receiving channel when the valve is opened.

When the valve710is rotated into its open position, the food product in the pump cavity69passes through the receiving channel73, past the open region730of the valve, and through the manifold27′ towards a manifold outlet727. As operation of pumping system26′ continues, pump61advances plunger68to compensate for the removal of food material through manifold27′, maintaining a relatively constant pressure on the remaining food in chamber69.

As plunger68advances, servo actuated cylinder64senses that plunger68is near the end of its permitted range of travel. When this occurs, pump62is actuated to advance plunger88through pump cavity89, compressing the food material in the second pump cavity in preparation for feeding the food from that cavity into manifold27′. When the rotary valve element is in a position to allow the contents in a pump cavity69to pass through the manifold, the rotary valve element is also in a position to prevent the contents of pump cavity89from passing through the manifold, thus allowing the contents of pump cavity89to be compressed due to a buildup of pressure.

When the food in the second pump cavity89is under adequate pressure, the input to manifold27′ is modified so that subsequent feeding of food product to the manifold is effected from the second pump cavity89with continuing advancement of plunger88of the second pump62. After the manifold intake has been changed over, pump61is actuated to withdraw plunger68from cavity69and to allow the pump cavity69to be once again filled with food product through top opening69a. The manifold intake is changed over using a rotary valve system which is discussed in further detail below.

Thereafter, when plunger88nears the end of its pressure stroke into pump cavity89, pumping system machine control transfers pumping operations to pump61again. The changeover process described immediately above is reversed; pump61begins its compression stroke, manifold27′ is changed over for intake from pump61, and pump62subsequently retracts plunger88back to the supply position shown inFIGS. 3 and 4to allow a refill of pump cavity89. This overlapping alternating operation of the two pumps61and62continues as long as the pumping system26′ is in operation.

The Manifold and Rotary Valve System

The pump manifold27′, shown inFIGS. 3,4, and7comprises a rotary valve system700(FIG. 6). The rotary valve system700comprises a rotary valve element710which is disposed within a fan shaped manifold27. The rotary valve element710rotates within the manifold27′ to direct the flow of food product from pump cavity69,89to the manifold outlet727. The rotary valve element comprises a solid portion720and an open region730. Rotation of the solid portion720into the first receiving channel73closes off communication between the first pump cavity69and the manifold outlet727, thus preventing the food product in the first pump cavity69from flowing into the pump manifold27. The extension of the plungers into the pump cavity while the solid portion720is turned toward the pump cavity allows the pressure to increase in the pump cavity to the desired level. When the solid portion720is within the first receiving channel73, the open region730is in communication with the second pump cavity89, which allows the food product in the second pump cavity to flow into the manifold outlet727. Once food product in the first pump cavity69reaches the desired level, the valve element is rotated such that the open region730is in communication with the first pump cavity, and the solid portion720is in position to allow the food product in the second pump cavity89to be compressed against it.

When pumping system26′ changes over between pump61and pump62, the input into the manifold27is accordingly changed to receive food product from pump62. The rotational position of the rotary valve element710, is actuated to its alternate operating conditions by actuator106(FIGS. 7 and 8). Actuator106retracts and extends piston rod105, to rotate the rotary valve element710. On one end106a, the actuator106is pivotally connected to a pin107(FIGS. 7 and 8). Extending from the actuator is a piston rod which is connected to a coupling member105awhich joins to the linkage member108.

FIGS. 8 and 9illustrate the piston rod105in its extended105band retracted105cstates. Linkage member108has an actuator connection end108a, and a rotary valve shaft connection end108b(FIG. 10). The linkage member108is connected to the actuator106at the actuator connection end108aby a pin109which extends through hole108band coupling member105ato allow the linkage member and the piston rod105to pivot relative to each other as illustrated inFIG. 8. The linkage member108is connected to the rotary valve element at the rotary valve connection end108bby a rigid connection to a shaft110(FIG. 11).

As illustrated inFIGS. 10 and 11, the rotary valve connection end108bof the linkage member108has a longitudinal groove111along the height of the linkage member108which is keyed to receive a protrusion112from the shaft110. The protrusion112allows the shaft to rotate with the linkage member108such that rotational movement of the linkage member108as a result of the extension or retraction of the actuator106, rotates the shaft110. The linkage member108is secured to the shaft110by surrounding the shaft110and is tightened about the shaft using fastening mechanisms such as screws113(FIG. 11).

The shaft110extends upwards from a lower machine housing. Within the lower machine housing, the shaft110is secured within a receiving member120to an attachment plate130by bolts131(FIGS. 12A-12E). A bearing shaft140is disposed within the receiving block120to receive the bottom end of the shaft110. The bearing shaft140receives a ball bearing150disposed around the bottom end115(FIG. 12A) of the shaft. The bearing shaft140is held in place by two bolts141which are disposed to overlap a portion of the bearing shaft and secure it in position within the receiving member120. The shaft110is then disposed within the bearing150and secured to the bearing150with a bolt151. Thus, when the shaft110is rotated by the actuating mechanism106, the shaft110is able to pivot about the bearing shaft140.

The shaft110on its top end116(FIG. 13) is connected to a rotary valve engagement member117. The top end116of the shaft extends upwards from the lower housing and is received by the rotary valve engagement member117. The top end116of the shaft passes through a bearing block118to extend above the lower housing.

As illustrated inFIGS. 4 and 14, the rotary valve engagement member117comprises a cylindrical top200with a rectangular perimeter extension210which extends from either side of the cylindrical top section200. The cylindrical top section200fits within the bottom section300of the rotary valve element710. The bottom section300of the rotary valve element has contoured recesses310which are snugly complementary in shape to the top of the cylindrical top section200and the rectangular perimeter extension210. The rectangular perimeter extension210that is snugly complementary with the contoured recesses310in effect key the engagement member117to the rotary valve element710to force the rotary valve element to move with the movement of the shaft110.

The manifold27′ wherein the rotary valve element is received comprises a top cover740and a bottom cover750(FIG. 14). Both the top cover and the bottom cover are secured to the manifold housing27aby fastening mechanisms such as bolts741and751. The bottom cover receives the bottom section300of the rotary valve element. The bottom section of the rotary valve element comprises a stepped section760which is circular and smaller in diameter than the diameter of the rotary valve element. The stepped section760is disposed in a complementarily shaped recessed section761in the bottom cover750. The bottom cover750has an opening766which allows the stepped section760to extend through the thickness of the bottom cover750to receive the cylindrical top200and its associated rectangular perimeter extension210.

The top cover740is disposed over the top745of the rotary valve element, and has a bottom surface742contoured to complementarily receive the stepped top surface of743the rotary valve element. The rotary valve element has a support rod780which extends between the bottom of the rotary valve element to the top of the rotary valve element. The support rod780is disposed off center from a central axis800of the rotary valve element. The support rod780is secured to the bottom of the rotary valve element by a threaded fastening mechanism781. The support rod780extends to the top of the rotary valve element wherein the top end of the support rod has a threaded bore790accessible from the top745of the rotary valve element.

The Removal Tool

The removal tool as illustrated inFIGS. 15-18comprises a removal bar800and vertical removal rod810. The removal bar800has a plate821with a longitudinal slot820through which the vertical removal rod810is passed. The vertical removal rod810has a handle portion811which does not pass through the longitudinal slot due to its larger size. The rest of the vertical removal rod810is passed through the longitudinal slot820and fastened to the threaded bore790at the top745of the rotary valve element. Once the vertical removal rod800is secured to the top745of the rotary valve element, the user raises the removal bar800to lift up the rotary valve element from its position within the manifold.FIG. 15illustrates the removal bar in position before and after the rotary valve element is removed. The vertical removal of the rotary valve element from its position within the manifold minimizes the number of parts that need to be removed to access the rotary valve element. Only the cover of the rotary valve element needs to be removed to allow the top surface of the cylindrical valve to be accessible to the removal tool.

The removal bar800is pivotally connected at a base end800ato a vertical support bar830which extends from the top surface of the manifold27′. As the removal bar830is lifted at a distal end800b, a rotational motion about the base end800ais translated to a vertical lifting motion at the vertical removal rod810by the sliding movement of the vertical removal rod810within the longitudinal slot820. To this end the handle portion811has a rounded bottom811athat slides on the plate821, through the slot820.