Vertical valve food patty molding machine

A high speed food patty molding machine capable of handling whole-fiber food products has two food pumps, each pump having a cavity with an inlet at once end, an outlet at the other end, and a plunger movable through the cavity. The two pump cavities are located adjacent to each other and separated by a common wall; a moldable food product is supplied into the inlet of each pump cavity. A manifold connects the outlets of the two pump cavities to a molding mechanism; a pump drive reciprocates the pump plungers in overlapping alternation and a valve seals off the outlet of each pump cavity whenever the plunger of that pump is moving toward its retracted refill position, so that there is a continuous pressurized supply of food product to the molding mechanism. Each pump cavity outlet is located at the juncture of the cavities common separation wall and the discharge end of its cavity. The outlets merge to form a common inlet to center of the manifold. A rotary valve member in the manifold inlet is reciprocally rotated between one operating position in which one pump cavity outlet is closed and the other pump cavity outlet is opened and another operating position in which the pump cavity outlet conditions are reversed. the food product must make a greater change of direction to flow to the portion of the manifold closer to the open outlet than to the portion of the manifold farther away from that outlet.

BACKGROUND OF THE INVENTION 
Food patties of various kinds, including hamburgers, molded "steaks", fish 
cakes, poultry patties, pork patties, and various vegetable patties are 
frequently molded in high volume automated molding machines Patty molding 
machines successfully adaptable to the forming of any of these food 
products are described in Richards Reissue U.S. Pat. No. Re. 30,096, 
reissued Sep. 18, 1979; Sandberg et al U.S. Pat. No. 4,054,967, issued 
Oct. 25, 1977; LaMartino et al U.S. Pat. No. 4,128,003, issued Jan. 8, 
1980; Sandberg et al U.S. Pat. No. 4,356,595, issued Nov. 2, 1982; 
Sandberg U.S. Pat. No. 4,697,308, issued Oct. 6, 1987 and Lindee U.S. Pat. 
No. 4,872,241, issued Oct. 10, 1989. 
Although any of these machines, and others as well, are capable of 
producing food patties of consistent size, weight and configuration on a 
high volume basis, substantial problems may be encountered when the 
machines are required to mold patties from food products which, unlike 
hamburger, have not been ground to relatively small particle size. Thus, 
it may be desirable to form patties from a food product that has not been 
chopped or ground; the starting material may consist of whole poultry 
breasts, large segments of pork or other meat, large fish fillets, or 
relatively large pieces of almost any food product that has an appreciable 
fiber content. Even in those machines specifically adapted to processing 
whole-fiber food products (e.g., Sandberg U.S. Pat. No. 4,697,308) 
maintenance of good texture in the finished patties may be a continuing 
problem. 
The molding mechanism of the Richards reissue U.S. Pat. No. Re. 30,096, 
also used in the specific machine illustrated in Sandberg U.S. Pat. No. 
4,697,308, utilizes a horizontally oriented manifold valve cylinder having 
two longitudinally displaced inlet slots which are alignable with 
respective outlet slots of two of side-by-side food pump cavities. The 
manifold valve cylinder has an elongated outlet slot which is angularly 
skewed longitudinally of the manifold valve cylinder to control the outlet 
pressure from the manifold to a molding mechanism. In later modifications 
of this molding mechanism, which are shown in U.S. Pat. Nos. 4,356,595; 
4,697,308 and 4,872,241, the elongated outlet slot from the manifold valve 
cylinder to the mold cavities is angularly enlarged to better handle 
fibrous food products containing large pieces with minimum deterioration 
of the large pieces and with no more than minimum distortion of the food 
patties when later cooked. The flow path of the food product through the 
modified manifold valve cylinder, whether ordinary hamburger or a 
high-fiber product, still requires a reversal of the direction of flow of 
the food product as one pump cavity outlet is closed by rotation of the 
manifold valve cylinder and the other outlet is opened, because each 
outlet discharges directly into only one end of the manifold valve 
cylinder, the end adjacent to its cavity. 
The rotation of the manifold valve cylinder to open and cylinder to open 
and close the pump cavity outlets tends to reduce the muscular texture of 
large pieces of a fibrous food product, due to shearing of these large 
pieces. The relatively small inlet and outlet openings in the manifold 
valve cylinder may create a large pressure drop as food products are 
pumped through this valve. Another problem which occurs because of the use 
of the relatively small inlet and outlet openings in the manifold valve 
cylinder is the tendency of large segments, in fibrous food products, to 
clog the manifold valve cylinder because of the inability to easily pass 
through these openings. Other operating problems with this basic mechanism 
may include undue "working" of the food product due to repeated reversals 
in flow direction, a need for higher pump pressures than desirable, and a 
tendency for some part of the food product to remain stationary or 
"freeze" in the manifold valve cylinder. 
SUMMARY OF THE INVENTION 
It is a principal object of the present invention, therefore, to provide a 
new and improved fibrous food product manifold and valve construction for 
a food patty molding mechanism that effectively minimizes the problems and 
difficulties heretofore described. 
Another object of the invention is to provide outlets for the food pump 
cavities of a molding mechanism that are adjacent to each other and 
discharge into the center of a mold plate manifold to minimize or 
eliminate reverse flow of the food product in the manifold as the outlet 
from one food pump cavity closes and the other opens. 
Yet another object of the invention is to provide a manifold inlet valve 
which affords a practically unobstructed passage for each pump outlet to 
discharge food product directly to an end of the manifold remote from the 
pump outlet. 
Still another object of the invention is to provide a manifold for a food 
patty molding mechanism that has diverging walls leading from its inlet 
valve to the filling ports of the mold mechanism and has walls that direct 
the flowing food product more efficiently to those mold filling ports. 
Accordingly, the invention relates to a high speed food patty molding 
machine comprising a food product molding mechanism and two food pumps, 
each pump comprising a cavity of predetermined width having an inlet and 
an outlet at opposite ends of the cavity and a plunger movable between a 
retracted position and a pressure position in which the plunger is 
advanced into the cavity. The pump cavities are located side-by-side with 
a common wall separating them. A supply means is provided for supplying 
moldable food product into the inlet of each pump cavity; a manifold 
connects the outlets of the two pump cavities to the molding mechanism, 
the manifold extending across the outlet ends of the pump cavities. Pump 
drive means are provided for driving the pump plungers in overlapping 
alternation so that at least one pump cavity always contains moldable food 
product under pressure. Valve means are provided for sealing off the 
outlet of each pump cavity from the manifold whenever the plunger for that 
pump is moved towards its retracted position, affording a continuous 
pressurized supply of moldable food product to the molding mechanism. In 
the improved manifold and valve means of this invention, each pump cavity 
outlet is located at the juncture of the common cavity wall and the 
discharge end of its cavity outlet, the two outlets merging to form a 
common inlet to the manifold. A rotary valve member is positioned in the 
manifold inlet and is reciprocally rotatable between one operating 
position in which one cavity outlet is closed and the other is open to the 
manifold inlet and another operating position in which the one pump cavity 
outlet is open and the other is closed.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 1 illustrates a food pump system 26 of the type shown and described in 
Richards U.S. Pat. No. Re. 30,096 which machine has been marketed for many 
years as the Formax F-26 machine of Formax, Inc. of Mokena, Ill. The 
disclosure of the Richards U.S. reissue patent is incorporated herein by 
reference and familiarity with it is assumed. 
The food pump system 26 is supplied with ground meat or other food product 
from a hopper that opens into the intake of the food pump system. The food 
pump system 26 includes two pump plungers 68 and 88 driven by piston rods 
67 and 87 actuated by hydraulic cylinders (not shown). Plungers 68 and 88 
are reciprocated in overlapping alternation in two pump cavities 69 and 
89, respectively, of a pump cavity enclosure 71. The pump cavity enclosure 
71 is divided into the two cavities 69 and 89 by a central divider wall 
72. The forward ends of the cavities 69 and 89 are closed by end walls 74 
and 94, respectively, which in the embodiment shown in FIG. 1 is a unitary 
wall. Relatively narrow slots 73 and 93 are formed, respectively, in each 
of the end walls 74 and 94. The slots 73 and 93 feed a manifold valve 
cylinder 101 which is horizontally mounted in manifold 27. 
The valve cylinder 101 includes longitudinally displaced inlet slots (not 
shown), alignable with the outlet slots 73 and 93, respectively. Cylinder 
valve 101 also has an outlet slot (not shown), which delivers food product 
to fill ports 111 leading to mold cavities in a mold plate; again, the 
mold cavities and mold plate are not illustrated. 
The food pump mechanism 26 is well known in the art from the aforementioned 
reissue patent to Richards and from the Formax F-26 patty molding machines 
manufactured and sold by Formax, Inc. of Mokena, Ill. This food pump 
mechanism is subject to the problems referred to above. 
FIGS. 2, 3, 4 and 5 illustrate a modification of the food pump mechanism 26 
that incorporates features of the present invention. In the modified food 
pump mechanism 126, FIG. 2, the mold cavities 169 and 189 are separated by 
a central divider wall 172 which terminates short of the forward end walls 
174 and 194 of the cavities. The forward end walls 174 and 194 of the 
cavities are inclined to converge at the divider wall 172, but terminate 
short of wall 172 to form adjacent discharge openings 173 and 193 at the 
center of a manifold 127. End walls 174 and 194 terminate in arcuate noses 
175 and 195, respectively, shown most clearly in FIG. 3 of the drawings, 
with each nose blending, respectively, into diverging walls 176 and 196 
leading into the manifold 127. The divider wall 172 between the cavities 
169 and 1893 also terminates in a nose 177 which is slightly concave; see 
FIG. 3. Plungers 168 and 188 reciprocate in alternation in the pump 
cavities 169 and 189. 
As can be seen most clearly in FIGS. 2-4 a rotary valve member 201 is 
mounted at the convergence of noses 175, 177 and 195. Valve member 201 
rotates about a vertical axis 200 to open and close communication between 
the pump cavities 169 and 189 and the manifold 127. Valve member 201 has a 
top wall 203, a bottom wall 205 and a partial circumferential side wall 
207, preferably a circular arc, joining the top and bottom walls. The side 
wall 207 has a sufficient circumferential extent to close either discharge 
opening 173 or 193 at any one time as can be clearly seen in FIGS. 2 and 3 
in which the discharge opening 193 from the pump cavity 189 is blocked but 
the outlet 173 of pump cavity 173 is open. The bottom wall 205 of the 
valve member 201 is journalled in a base plate 211 that is a part of the 
manifold 127 and is attached to a disk 213 which is in turn connected to a 
shaft 215 which is reciprocated angularly to rotate the valve member 201 
between alternate positions, closing and opening the outlet openings 173 
and 193 of the pump cavities 169 and 189 in alternation. The top wall 203 
of the cylindrical valve is formed with a step 217 which is journalled in 
a ring 219 bolted to the manifold 127. 
Thus, the valve member 201 is reciprocally rotatable between two operating 
positions which alternately open one pump cavity outlet, such as outlet 
173, and close the other pump cavity outlet, such as outlet 193, and vice 
versa. In the positions shown in FIGS. 2, 3 and 4 of the drawings, the 
arcuate wall 207 of the valve 201 closes the discharge outlet 193 of the 
pump cavity 189 and provides an unobstructed passage from discharge outlet 
173 of the pump cavity 169 into the manifold 127. When the valve member 
201 is rotated to its other position (about 90.degree. in the illustrated 
embodiment) the arcuate wall 207 closes the discharge outlet 173 of the 
pump cavity 169 and provides an unobstructed passage from discharge outlet 
193 of the pump cavity 189 into manifold 127. In either operating position 
of the valve, the flat chordal surface 221 of arcuate wall 207 of valve 
201 provides a smooth continuity between the nose 177 of central divider 
wall 172 and one or the other of the diverging walls 176 and 196 of the 
manifold 127, thereby permitting an unobstructed flow of food product from 
either one of the pump cavity discharge outlets 173 and 193 into the 
manifold 127. 
It should be noted that because of the central location of the pump cavity 
discharge outlets 173 and 193 and the canted alignment of discharge of 
each outlet relative to the manifold 127, each pump cavity discharge 
outlet has almost a straight line of discharge flow into the end of the 
manifold 127 which is not immediately adjacent its pump cavity; the path 
of travel of food product from a pump outlet to the end of the manifold 
127 opposite its pump cavity requires a slight turn in direction of flow. 
This pattern of flow of the fibrous food products from the pump cavity 
discharge outlets 173 and 193 (see arrows A in FIG. 2) virtually 
eliminates the problem of reverse flow of food product in the manifold 127 
in those intervals when the arcuate wall 207 of the control valve member 
201 is reciprocated to open one discharge outlet and close the other. 
Further, because the food product does not experience a change in 
direction of flow as it passes valve member 201 into manifold 127, as was 
the case with previous horizontally oriented manifold cylindrical valves, 
there is an apparently lower pressure drop through the manifold inlet 
valve and less tendency for large segments of the food product to clog the 
manifold inlet. The tendency to clog the vertical cylindrical valve of 
this invention is eliminated in comparison with previously used horizontal 
valves because the passage adjacent the flat chordal surface 221 of the 
arcuate wall is essentially unrestricted. 
To more efficiently direct the flow of food product from the vertical valve 
member 201 to the filling ports 231, which are located at the top of the 
manifold 127 (FIGS. 2-4) and to fill the mold cavities 233 (FIGS. 3, 4) of 
the mold plate 291 (FIG. 4), the wall of the manifold located opposite to 
the diverging walls 176 and 196 is formed with horizontally extending 
peaks and valleys facing the valve member 201, as shown in FIGS. 3 and 4. 
These peaks and valleys form channels that direct the fibrous food 
products from the cylindrical valve 201 to the filling ports 231. The 
centrally positioned horizontally extending peak 241 is located directly 
opposite the valve member 201 and extends the greatest horizontal distance 
towards the pump cavity discharge outlets 173 and 193. A pair of peaks 243 
of mirror image asymmetrical shapes are positioned on opposite sides of 
the central peak 241 to form valleys 245, with a filling port 231 located 
above each valley. The walls of the peaks 243 which face the peak 241 
extend generally at right angles to the longitudinal side of the manifold 
127 while the outer walls 246 of the peaks 243 are inclined to the 
longitudinal wall of the manifold. Peaks 243 extend a shorter horizontal 
distance towards the valve 201 than does the central peak 241. The 
outermost peaks 247 form pockets or valleys 251 with their adjacent peaks 
243. A filling port 231 is located above each pocket or valley 251. 
Valleys 253 are formed between the peaks 249 and the end walls 255 of the 
manifold. Each peak other than the central peak 241 has an inwardly facing 
straight wall and an outwardly facing inclined wall to form channels or 
valleys with the walls of adjacent peaks to direct the flow of fibrous 
products to the filling ports 231 with a minimum of resistance to flow and 
a minimum tendency for reverse flow. The channels or valleys between the 
adjacent peaks lie generally on a straight line relative to one of the 
discharge outlets 173 or 193 from the pump cavities 169 and 189 
respectively. 
As can be best seen in FIG. 4, the mold cavities 233 are formed in a mold 
plate 291 which is reciprocally mounted for movement from left to right as 
viewed in FIG. 4. The mold plate 291 is shown in its discharge position in 
phantom lines to the right of FIG. 4. In the discharge position, the mold 
cavities 233 align with knockout cups 293 of the same shape as the mold 
cavities. The knockout cups 293 move up and down to knock a patty out of 
the mold cavity 233 for movement away from the molding mechanism. 
FIG. 5 of the drawings is a chart showing how the movement of pump cavity 
plungers 168 and 188 maintains pressure on the food product in the 
manifold 127. Plunger 168 is exerting maximum pressure on the food product 
in its cavity 169 and continues to maintain this pressure as plunger 188 
reaches its maximum pressure. Shortly after plunger 188 starts to exert 
its maximum pressure, plunger 168 is withdrawn to refill its pump cavity 
with food product and the pressure in its cavity drops to its minimum, 
effectively zero. This cycle continues as plunger 168 again starts to 
increase pressure and reaches its maximum pressure slightly before plunger 
188 is retracted to reduce the pressure it exerts against the food product 
and permit refilling of its pump cavity 189. Thus, with the overlap of the 
food plungers a substantially constant pressure is maintained on the 
fibrous food products in manifold 127.