Loin pull and rib cut machine

[57] ABSTRACT

A machine for automatically performing loin pulling and rib cutting operations on pork sides, the loin pulling operation including a rib sawing operation, a loin cutting operation and a loin push-off operation, and the rib cutting operation leaving the ribs on the belly part of the pork side. The machine automatically feeds pork sides, and cuts, saws and mechanically separates portions thereof.

Claims, 26 Drawing Figures

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v dni/enioro:

JiichardDddehel, C/arerceLJfar-zzzs; damecD. dlhebel xEichard D. Do er her

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Clarence (tfaj-nes' CD. rt/lfeebel

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Jrit/cnbors: RichardJR.d^ebel, Ciarc/iceD/far/nd, daraesl). dteebd _&amp; Richard£Doerfer

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LOIN PL'LL AND RIB CUT MACHINE

Matter enclosed in heavy brackets appears in the original patent but forms no part of this reissue specification; matter printed in italics indicates the additions made by reissue.

BACKGROUND AND SUMMARY OF THE INVENTION

One object of the invention is to provide a functional machine for automatically completing all of the above enumerated operations with less manual labor and more uniformity of the resulting pork cuts than arc possible by trained operators.

Another object is to provide a mechanism to saw through the ribs in a self-determined direction depending on the size and shape of the pork sides.

Still another object is to cut the loin in a predetermined pattern conforming to the natural configuration of the pork side and with a controlled quantity of fatback.

A further object is to automatically remove the loin from the remainder of the side and allow such remainder to proceed to the rib cutting mechanism of the machine.

Still a further object is to automatically cut out the remaining ribs from the side in a plane as close to the ribs as possible and with a blade which is withdrawn in a line corresponding with the ends of the ribs, thus minimizing the meat lost with the ribs.

With these and other objects in view, our invention consists in the construction, arrangement and combination of the various parts of our loin pull and rib cut machine, whereby the objects above contemplated are attained. as hereinafter more fully set forth, pointed out in our claims and illustrated in detail on the accompanying drawings, wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a loin pull anti rib cut machine embodying our invention, slightly more than onehalf (the right half) of the machine being.shown;

FIG. 2 is a vertical sectional view on the line 2—2 of FIG. 1;

FIG. 3 is an enlargement of a portion of FIG. 2 showing mechanism for initially advancing a pork side into the machine;

FIG. 4 is a vertical sectional view on the line 4—I of FIG. 3;

FIG. 5 is a vertical sectional view on the line 5—5 of FIG. 3;

FIG. 6 is an enlargement of a transversely mounted tapered lug shown in FIGS. 4 and 5;

FIG. 7 is an enlarged vertical sectional view on the lines 7—7 of FIGS. 1 and 2;

FIG. 7A is a diagrammatic view representing a continuation of the left hand end of FIG. 7 and showing an arrangement for permitting both vertical and horizontal movements of a secondary carriage member;

FIG. 8 is a detail sectional view on the line 8—8 of FIG. 7;

FIG. 9 is a plan view of the parts of our machine shown in FIG. 7 and shows a loin scribe saw, a scribe saw shoe and a loin pull knife in an initial position during the operation of the machine;

FIG. 10 is a vertical sectional view on the line 10—10 of FIG. 1 1 shotting a pork side operated switch;

FIG. 11 is a view similar to FIG. 9 showing the saw.

shoe and knife in a different position during a further operation of the machine;

FIG. 12 is a view similar to a portion of FIG. 11, and as taken on the line 11 —11 of FIG. 7 to show more clearly the relation of details of the saw. shoe and knife:

FIG. 13 is an enlarged side elevation of a portion of FIG. 2 above the bracket 13 thereof and as taken on the line 13—13 of FIG. 9;

FIG. 14 is an enlarged elevation of a portion of FIG. 2 as taken on the line 14—14 thereof;

FIG. 15 is a sectional view taken on the line 15—15 of FIG. 14;

FIG. 16 is a sectional view taken on the line 16—16 of FIG. 14;

FIG. 17 is an end view of a drive drum shown in FIG. 14 and as viewed at the line 17—17 thereof;

FIG. 18 is an enlarged elevation of a portion of our machine adjacent the line 18—18 of FIG. 2;

FIG. 19 is an enlarged sectional view of a portion of FIG. 18 found in the lower left quadrant thereof;

FIG. 20 is a detail sectional view on the line 20—20 of FIG. 19;

FIG. 21 is an enlarged elevation of a portion of FIG. 2 above the bracket 21 and shows the parts in reverse to better illustrate details thereof;

FIG. 22 is an enlarged end view of a roller illustrated in FIG. 21;

FIG. 23 is an enlarged elevation of the portion of FIG. 2 above the bracket 23 thereof;

FIG. 24 is a diagrammatic view of eight air cylinders and the controls therefor used in our machine; and

FIG. 25 is a plan view of the portion of the machine shown in FIG. 23.

LOIN PULL OPERATION

On the accompanying drawings we have used the reference numeral 26 to designate a pork side convevor to which right pork sides (RS) may be delivered by an infeed conveyor 27. A series of rollers 29 are illustrated in FIGS. 1 and 2 to span the space between the discharge end of the conveyor 27 and the intake end of the conveyor 26. The conveyors 26 and 27 mav be driven in synchronism with each other and in any suitable manner such as· by a motor 31 driving a speed reducer 33, and through a chain 35 driving a shaft 37 as shown in FIG. 1. FIG. 1 also illustrates a chain drive 39 between the intake end of the conveyor 26 and the discharge end of the conveyor 27.

The direction of travel of the conveyors is in accordance with an arrow 43 adjacent the right hand end of FIG. 1. Considering our machine as oriented in accordance with the arrow 43, the left hand edges of the conveyors 26 and 27 are cut off with broken lines 26a and 27a. At 41 the fore-and-aft center line of the machine is indicated.

The mechanism of our machine in FIG. 1 is somewhat diagrammatically illustrated with reference characters F indicating various parts of a stationary frame. Such mechanism is for the purpose of automatic loin pulling and rib cutting operations for right pork sides whereas the rest of the machine (to the left of the center line 41 ) is identical except it is a mirrored opposite of that portion of the machine to the right of the center line and is for left pork sides. We therefore deem it unnecessary to illustrate the left half of the machine.

In FIG. 1 we show right pork sides RS to indicate the position thereof on the infeed convevor 27 in relation

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:o a side rail 28 against which the operator of the ma chine holds the side RS with the backbone of the side ying parallel to and in full length contact with the rail. This rail is corrugated in vertical cross section as shown n FIG. 4 to reduce fractional drag on the sides RS .is hey move through the machine. The ribs 45 of the &gt;ork side RS (shown in FIGS. 5 anti 13) are uppermost ind are transverse to the direction of travel of the ineed conveyor 27 and the pork side conveyor 26.

The pork side RS is moved toward the cutting and awing section of the machine, which will later be.decribed, by the pork side conveyor 26. The side RS is icld down and pulled toward a cutter arm 30 (which :arries a loin scribe saw 40 and a loin pull knife 42 ) by tud ponts 32 mounted on a gripper chain 34. The peed of the pork side conveyor 26 and the. gripper :hain '34 are synchronized, and a gripper chain rider irm 36 is inclined downwardly in the direction of travel o better hold the side RS in a firm position against conveyor lugs 38 (see FIGS. 3. 4, 7 and 11 ) as it reaches ind passes through the loin scribe saw 40 and the loin lull knife 42 (see FIGS. 7, 9. 11 and 13).

The gripper chain 34 contains transversely mounted ugs 44 with five of the pointed studs 32 mounted on :ach lug. The lugs 44 are tapered as shown in FIGS. 4, i and 6 in order to better conform to the contour of the lack bone of the side RS which is pulled by them hrough the loin scribe saw 40 and the loin pull knife 12. The rider arm 36 is forced down against the center if the side RS by its own weight as well as by an adjustiblc pneumatic cylinder Cl acting as an air spring. Adustment is accomplished by supplying compressed air :o the cylinder through an adjustable pressure regulator PR1 as shown diagrammatically in FIG. 24. This action teips to position and hold the side RS for better sawing ,md cutting action.

At the outgoing end of the gripper chain 34 there is i loin depressor foot 48 (FIGS. 1 and 3) carried by a frame 55 for the gripper chain, which forces the side RS off the gripper chain 34 and down against the pork ode conveyor 26, and also holds the side RS in position for sawing and cutting.

The gripper chain 34 as shown in FIGS. 3 and 4 is of Jual character and is trained around a pair of dual tprockets 47 and 49, shafts 51 and 53 being provided therefor. The frame 55 is associated with the gripper ehain. its sprockets and shafts, and is pivoted about the axis of the shaft 51. The left hand end of the frame 55 is supported by a yoke 57, a piston rod 59 and a pneumatic cylinder C2. The cylinder C2 also acts as an air spring, a pressure regulator PR2 being provided therefor as shown in FIG, 24. The rider arm 36 is supported by a piston rod 63 and the pneumatic cylinder Cl, the right hand end of the arm being mounted on a bracket 55 pivoted about the axis of the shaft 51. The frame 55 is provided with three spring biased hold-down rollers 67 (see FIG. 5) so as to variably conform the successive stud points 32 to the side RS as it passes under them as shown by dot-and-dash lines in FIGS. 3 and 4.

For rotating the shaft 51 and thereby actuating the gripper chain 34 a drive chain 69 shown in FIG. 1 is driven from a cross shaft 71 which is the output shaft from a speed reducer 73 driven by an electric motor 75. Between the chain 69 and the shaft 51 a safety slip clutch 25 is preferably provided for protection of the drive mechanism for the loin pull and rib cut operations. The shaft 71 extends transversely of the machine .508 to drive the left side mechanism in synchronism with the right side mechanism, and the speed reducers 33 and 73 are adjusted for Obtaining the same surface speed for the gripper chain 34 as for the conveyors 26 and 27.

An interval of at least 24 is allowed betw een successive sides RS on the conveyors 26 and 27 as shown in FIG. 1 in order that the cutter arm 30 shown and the loin scribe saw 40 shown in FIGS. 7, 9, 11 and 12 can he returned to their starting position by the automatic action of mechanical linkage including a lex er 50 secured to the cutter arm 30 and actuated by a [hydraulic J pneumatic cylinder C3 acting as an air spring through the action of a pressure regulator PR3 shown in FIG. 24. The entire assembly is pivotally mounted by securing the arm 30 to a vertical shaft 77 shown in FIGS. 7, 9 and II, the shaft 77 being journalled in a bracket 79 secured to a secondary carriage member 76, as shown in FIG. 7A. the carriage member 76 has a pair of rods 81 which arc freely and vertically slidable in a primary carriage member 83. The carriage member 83 is freely and horizontally slidable on a pair of rods 85 carried by the frame F of the machine.

FIGS. 11 and 12 show a normal position for the saw 40 parallel to the travel of the pork side conveyor 26, and FIG. 9 shows an angularly disposed position relative thereto for purposes which will hereinafter appear. The cutter arm 30 also carries a scribe saw shoe 52 (FIGS. 7 and 12) which functionally positions both the loin scribe saw' 40 and the loin pull knife 42 for their initial cuts. The shoe 52 is held down by the weight of the cutter arm 30 and the elements 76 and 81 shown in FIG. 7A, and is pulled horizontally by a cable 54 terminating in a counterweight 56 shown diagrammaticallv in FIG. 7. The angle of the cable 54 is such that vertical as well as a horizontal pull is obtained, the vertical pull involving the rods 81 sliding in the primary carriage member 83 and counteracting to some extent the weight of the arm 30, etc. as above referred to. and the horizontal pull involving the member 83 sliding on the rods 85. Thus, the dual purpose of the counterweight 56 is to off-set the weight of the cutter arm 30, etc. for easier maneuverability and to pull the scribe saw shoe 52 against the up-curved portion of the ribs 45 of the side RS according to the arrow 87 in FIG. 7. FIG. 7 also has legends as to parts of the side RS to clarify reference to the operations on the side hereinafter referred to.

During initial contact of the saw blade 40 with the side RS, it is diagonal (FIG. 9) to the line of conveyor 26 travel and the horizontal direction of its cut is determined by the position of the scribe saw shoe 52 at it rests on the side and follows the contour of the back bone of the side. The vertical level of the saw cut is determined by the elevation of the scribe saw shoe 52 throughout the entire travel of the side RS thereunder. The scribe saw 40 is a circular saw blade driven by an angle head drixe 130 anil a flexible power cable 58 (see FIGS. 1 and 13) from a motor 60 centrally mounted above the work area on an upper portion of the frame F. A scribe saw arm 64 which carries the shoe 52 and the saw 40 are horizontally stabilized by a pair of rollers 66 which ride up and down in a straddling position on the left hand (considered according to arrow 43) vertical side 42a of the loin pulling knife 42 as shown in FIGS. 7 and 12. The loin pull knife 42 is mounted on the cutting arm 30 but during part of the cutting cycle it is indepcndcntK controlled as to direction and elex.i·

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tion of cut by mechanical linkage 68 ( FIGS. 7, 9 and 11) pivoted to a bracket 62 mounted on the secondary carriage member 76. The loin pull knife 42 is positioned slightly behind the scribe saw 40 with the vertical portion 42a always following directly behind and in line with the scribe saw through the cut made through the rib bones 45 by the saw. In FIG. 9 it will be noted that the vertical portion 42b of the knife 42 is parallel to the arrow 43 but the portion 42a is diagonal (the initial contact mentioned at the beginning of this paragraph). During the last part of the loin cut operation shown in FIG. 11 both portions 42a and 42b are parallel to the arrow 43 as permitted by flexibility of the knife 42.

A unique feature of the vertical positioning mechanism for the loin pull knife 42 is a stationary cam track 70 (FIG. 13) and a roller 72 which serve to lift the knife 42 at the moment coinciding with the position of the side RS when the.shoukier thereof has passed the knife. In this way the knife rises to follow the contour of the side RS and is then lowered to resume cutting the loin. The roller 72 is carried by dual arms 46 pivoted at 61 on a bracket 89 carried by the cutter arm 30, and is operatively connected by links 91 to the upper end of a piston rod 93 in a cylinder C4. The piston rod 93 acts normally as a supporting guide rod for the scribe saw 40 and the shoe 52 through the scribe saw arm 64. The cylinder C4 can be pneumatically actuated by the operation of a jam valve J ( FIG. 24) for lifting the saw and shoe as will hereinafter appear.

The initial position (FIG. 9) of the loin knife 42 is determined by the vertical and horizontal position of the scribe saw^: shoe 52. However, as the side RS is moved further along by the pork side conveyor 26 it depresses a wire loop switch actuator 74 (FIGS. 9, 10 and 11 ) of a micro-switch SW1 which then activates the hydraulic cylinder C3 (see FIG. 24) which repositions the entire cutter arm and thereby the saw 40 and the knife 42 into another position shown in FIG. 11 by the switch opening a solenoid valve SV1. FIGS. 7 and 13 also show the parts in this other position.

The solenoid valve SV1 is a double acting type with spring return, supply inlet 1, normal outlet 2, operated outlet 3 and exhaust 4. Solenoid, valves SV2 and SV3 referred to later, are the same type. The cylinder C3 is also under control of the switch SMI and the solenoid valve SV1 (sec FIG. 24).

In changing from the initial position of FIG. 9 to this other position shown in FIG. 11, the roller 72 passes over the hump of the cam track 70 as further explained hereinbefore. Thus, a momentary lifting of the loin pull k'nife 42 is effected and it is then returned to its previous elevation but in its new direction of cutting action shown in FIG. 11. This is necessary in order to follow the natural contour of the side RS at that point. The saw and knife are now in a position to continue cutting down the length of the side RS in the direction of the conveyor 26 instead of diagonally. This change in cutting direction is necessary due to the fact that the loin (shaded area on the sides RS in FIG. 1 ) is broader at the lead end than it is shortly thereafter. The result is. first a curved saw cut path, and then a straight saw cut path down the length of the side RS.

Also when the cutter arm 30 is riioved into this final position of FIG. 11,, the vertical portion 42b of the loin pull knife 42 contacts a stop button 78 as in FIG. 7 to close the loin knife (spring its rides closer together) so it will cut a. narrower horizontal portion of the loin from

Copy the side RS as shown. The knife will be found more open in FIG. 9. Such closing of the knife is possible because of its flexible character and is permitted by the mechanical linkage 68. During this time the knife 42 is also positioned closer to the side rail 28.

The stop button 78 is automatically adjusted by means of a cam lever 127 shown in FIG. 7 pivoted to the frame F and carrying a cam roller 128. One of the rods 81 as shown in FIG. 7 has a roller engaging arm 10 129 which at times engages the roller 128. The stop button 78 controls the amount of fat left on the loin. This is accomplished by the variation in elevation of the scribe saw shoe 52 which rides on the rib section. As the scribe saw shoe 52 changes elevation the cutter arm 15 30 also changes elevation. This in turn actuates the stop button 78 to control the horizontal location of the knife, thus controlling the fat thickness left on the loin after cutting. Normally the heavier or thicker the side RS is, the thicker the fat back. Thus, distance 100 in20 creases on heavier sides to adjust for the thicker fat backs.

When the side RS has tripped the switch wire 74 to close the switch SW1, a loin drive-drum 80 (FIGS. 14 and 17) is automatically forced down on the already 25 cut portion of the loin which is still lying on top of the remainder of the side RS in order to help pull the entire side through the loin cutting and sawing operation and on to the next station of the machine. This is accomplished through a pressure regulator PR5 by a cylinder ^3&lt;) C5 also actuated by the switch SW1 and the solenoid valve SV1 as illustrated diagrammatically in FIG. 24. The cylinder C5 normally keeps the drum 80 raised by flow of compressed air from outlet 2 of the valve SV1.

Two sizes of loin knives 42 may be used on our ma³-^s chine depending on whether regular or heavy sides RS are being processed. With respect to these pork sides, regular sides are 24 to 30 inches long and heavv sides are 30 to 40 inches long as a general rule. A heavier and wider knife is used for heavy sides and requires an ⁴⁰ adjustment along the arm 30 which holds the scribe saw 40 in order to cut a wider loin portion. A wing nut 82a is provided for this purpose (FIGS. 7, 9, 11 and 13). The knives 43 themselves are secured to the cutter arm 30 for quick exchange by a wing nut 82.

Preceding the wire loop switch actuator 74 and extending from the lower edge of the corrugated side rail 28 is a deflector bar 84 (FIGS. 7 and 8) which forces the fatback of the side RS up against the loin knife 42, thus giving a maximum sized cut of loin by preventing the fatback from packing down into the adjacent corner between the frame F and the rail 28.

After the side RS has passed by the wire loop switch actuator 74 and the actuator has returned to its normal ,.,. position, the cylinder C3 which controls the two positions ( FIG. 9 and 11 ) of the saw 40 and the knife 42 automatically returns the saw and knife to their respective starting positions of FIG. 9 through the action of the switch SW1 and the solenoid valve SV1 and at the same time the loin drive-drum 80.is raised through the action of the same switch and valve shown in FIG. 24.

In an emergency the machine operator can raise ( and later lower) the gripper chain rider arm 36 (Cl ). the gripper chain 34 (C2). the saw 40 and shoe 52 ( C4 ) ₆- and the drum 80 (C5 ) pneumatically by closing (and later opening) the jam valve J as evident in FIG. 24.

The drive drum 80 as shown in FIGS. 1. 2 and 14 to 16 inclusive is mounted on a shaft 86 connected bv universal joint 101 with a shaft 122 which is journalled in

Re. 28.508 the frame F. The shaft 122 is driven by a chain 121 as shown in FIG. 1 from a counter shaft 97 which in turn is driven by a chain 99 front the shaft 51. A bearing 103 is supported by a yoke 105 and a piston rod 107 of the cylinder C5, and the shaft 86 is guided by a bearing 109 thereof movable in a slot 111 of a portion of the frame F of the machine.

After the loin has been pulled, the side RS (now in two pieces) proceeds with the pork side conveyor 26 toward the next (loin push-off) operation. As the corrugated side rail 28 ends, the back bone side of the side RS is held in position by a horizontal guide rail bar 88 (FIGS. 18 and 21) located in line with the railing 28 and above the conveyor 26. This guide rail bar is movable. pivoting outward from an axis 113 the same as a pair of spring loaded kick off shoes 90. FIG. 19 shows a spring 119 to effect such loading.

The kick off shoes 90 are inclined upwardly at their lead ends (see FIG. 21 wherein the view is from the side of the machine opposite that shown in FIGS. 1,2, 3 and 13 so travel is opposite as indicated by an arrow 120 in FIG. 13) so that they may ride up on the side RS as it proceeds down the conveyor 26. The shoes 90 arc located on either side of a pair of freely rotating knob covered drums 92 as shown in FIG. 21. The kick off shoes 90 are slidably supported in a welded tube assembly 94 and the pair of shoes and the guide rail bar 88 move together as a unit about the axis as shown by solid and dot-and-dash lines in FIG. 18. Also the shoes 90 have limited oscillation possibilities as illustrated in FIG. 20 to allow them to align themselves for the purpose of dropping into the scribe saw cut at 123 FIGS. 7 and 13).

When the side RS actuates a trip arm 96 shown in FIG. 21, an actuating arm 98 forming part of the assembly 94 is pivoted from the full line position in FIG. 18 to the dot-and-dash line position thereof by a cylinder C6 so that the kick off shoes 90 will drag transversely across the side RS, drop into the saw cut at 123 and push the pulled lion 124 off the side of the conveyor 26 and onto a chute 125 where it falls into a loin cart or onto a loin conveyor 131 or the like. The trip arm 96 closes a switch SW2 which through a solenoid valve SV2 as shown in FIG. 24 controls the flow of compressed air to the cylinder C6 for moving the actuating arm 98 from the full line position to the dot-and-dash line position of FIG. 18. At the same time the switch SW2 effects lowering of the knob covered drums 92 (controlled by a pressure regulator PR7a) which are normally in the raised position through the action of a cylinder C7 and a pressure regulator PR7 (see FIGS. 18, 21 and 24).

Slightly proceeding the above operation and in order to hold the side RS in position during the loin push-off operation, the pair of transversely mounted knob covered drums 92 drop onto the remaining rib section of the side RS under the pressure of the pneumatic cylinder C7. The two drums 92 are supported on a side mounted frame 102 which pivots up and down. This holding operation is thus also triggered by the trip arm 96 of the switch SW2. The knob covered drums 92 are raised automatically after the side RS has passed by and allowed the trip arm 96 to resume its normal vertical position shown in FIG. 21.

RIB CUT OPERATION

After the loin has been removed, the remaining por lion of the side RS proceeds down the conveyor 26 and is contacted by the first of two knobbed drive drums 104 (larger than the first pair of drums 92) powered to propel the side RS through a rib cutting knife 106 (see FIGS. 23 and 25 ) at a speed synchronized with the conveyor drive. Such synchronized drive is attained by a chain 126 from the shaft 97 as shown in FIGS. 1 and 2. This portion of the conveyor has a side rail 28a similar to the side rail 28. The rib cutting knife 106 is arranged diagonally to the direction of conveyor travel as shown in FIGS. 1 and 25 for two reasons;

(1) By entering the side RS at one corner rather than along the entire leading edge of the knife, the meat is more easily drawn past the knife.

(2) The ends of the ribs are diagonal to the side RS itself and thus when the knife 106 is elevated to withdraw it from the side RS it leaves the meat on a diagonal line corresponding to the ends of the ribs.

The rib knife 106 is sharpened with the bevel on the upper side and is mounted with the leading edge of the knife higher than the trailing edge in respect to the pork side conveyor 26 as shown in section at 106a in FIG. 23. This arrangement provides an angle of attack which forces the knife up in a plowing effect which forces it to cut close to the bottom of the ribs 45. A hold down plate 108 is mounted at the bottom of and between the two drive drums 104. Its purpose is to prevent the side RS from sticking to the first drive drum and to force the side RS against the lugs 38 of the conveyor 26. The rib cutting knife 106 is automatically positioned vertically by the thickness of the side RS and it cuts immediately under the ribs. The angle at which the rib cutting knife 106 is set and the angle at which the edge is sharpened as above described satisfies a requirement that the knife cut as close to the under side of the ribs as possible. This knife is designed with a curvature throughout its length which corresponds to the natural curvature of the ribs and thus provides most effective cutting.

When the leading edge of the side RS strikes an actuator wire 110 located downstream of the second drive drum 104 (see FIGS. 23 and 25), there is a delayed action pneumatic force supplied to a pair of arms 116 and 116a on which the drive drums 104, hold down plate 108 and rib cutting knife 106 are mounted by a pneumatic cylinder C8 (normally under control of a pressure regulator valve PR8), lifting the arm 116-116a upward and pulling the knife 106 free from the meat. This withdrawal of the knife 106 is so timed as to cut off the ribs on a line corresponding to the upstream ends thereof. Part of the arm 116a serves as a housing for the chain 126.

The delayed action referred to may be had by the arrangement shown diagrammatically in FIG. 24, a switch SW3 being actuated by the wire 110 and in turn energizing a solenoid valve SV3( D). the “D” indicating a delayed action type of valve.

Since the knife 106 is the lowest member attached to the arm 116-116a, the side RS (FIGS. 23 and 25) is no longer propelled by the pair of drive drums 104. Therefore. an independently mounted drive wheel 114 continues to pull the side RS down the conveyor and free of the rib cutting knife 106. The drive wheel 114 and its drive motor 115 are mounted in a separate pair of arms 132 and 132a which are free to move up and down, loosely pivoting on pivot pins 118 at opposite sides or the right and left sides of the machine. The two

Re. 28,508 arms 132 ami 132a. and a cross member 117, form a frame for mounting the wheel 114 for the side RS, a similar wheel (not shown ) for the other pork side ( also not shown) and its motor 115. The loose pivoting referred to allows either of the drive wheels 114 (the right hand one shown) or the left hand one (not shown) to independently seek their own elevation as dictated by the right and left pork sides respectively.

An operator at the discharge end of the machine can lift the ribs from the remaining portion of the side RS and place them in a separate container, conveyor or the like, thus completing the rib cutting operation.

With further reference to FIG. 24, only the essential operation of the pneumatic circuit is disclosed. Solenoid valves arc indicated as actuated by switches without going into detail with respect to electric circuits therefore. Since circuitry of this character is well known in the automatic machine art. we deem it unnecessary to illustrate the same in detail. FIG. 24 also serves as a summary of the machine as all operations arc shown in sequence, cylinders Cl and C2 representing a preliminary feed station, cylinders C3 and C4 a loin pull station, cylinder C5 an intermediate feed station. cylinder C6 a push-off station, cylinder C7 a second intermediate feed station, and cylinder C8 a rib cut station. Beyond the rib cut station, the independent motor driven wheel 114 of FIG. 23 constitutes a final feed station.

From the foregoing specification it will be obvious that we have provided a loin pull and rib cut machine which greatly reduces the normal work and hand labor Of loin pulling and rib cutting operations, thus reducing the labor force. At the same time the quality of the loin pulled and the ribs cut are maximum and labor costs are reduced because of reducing the amount of subsequent hand trimming of fat from the loins and ribs. The operation by our machine are performed in such manner that the parts thereof are automatically adjusted for each cutting operation to the individual size and shape of each side RS. While these operations are being performed by the right side of the machine, the left side is simultaneously performing the same operations on left sides in an obvious manner, and the only attention required by operators is one to feed the right and left sides onto the infeed conveyor 27 and another to remove the ribs and rib meat from the fat backs which are discharged off the pork side conveyor 26 (upper left hand end in FIG. 1).