US 2972747 A
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Description (OCR text may contain errors)
Feb. 28, 1961 H. Kl-:LEM 2,972,747
MACHINE FOR TYING CASINGS 2 Sheets-Sheet 1 Filed Aug. 19, 1958 INVENTOR. Howard K elem BY v 7A Tomvfy Feb.28, 1961 H. KELEM 2,972,747
MACHINE FOR TYING CASINGS INVENTOR. Howard K elem BY a z 7 A TORNEY United States Patent() 2,972,741 e MACHINE Fon TYING cAsINGs Howard Kelem, Far Rockaway,.N.Y. Global Indusgis# )Machinery Corp., 686 Henry St., Brooklyn 31,
Filed Aug. 19,1958, Ser. No. 755,945
18 Claims. (Cl. 1-95) This invention relates to machines for applying a metallic fastener to the `otherwise open end of a food holding casing and particularly to that type capable vof tying and sealing the twisted or pleated end portion .of a filled or empty casing.
K The invention contemplates the provision vof a simple machine adapted to compact an end portion, to feed automatically initially U-shaped metallic fasteners around and out o-f contact with the compacted casing .end portion, then to bring the squared olf end edges of the fastener into pressed fitted contact with each other to form a cylindrical ring aro-und said end portion, and finally to indent the fastener to an extent sufficient to effect a permanent seal and to attach the fastener immovably to the casing end portion.
The invention further contemplates the provision of a fastener applying machine wherein the operator'need merely supply fasteners to a hopper and insert the compressed `or crimped casing end into the machine and operate a handle control to a valve, to seal adequately casing made of a considerable variety of materials and in a considerable range of sizes without danger of damaging casings even of fragile materials such as cellulose, the machine being adjustable to conform to the particular type of casing operated upon.
The invention further contemplates the provision lof simple and dependable air operated means for aligning in a row and for feeding fasteners automatically to the setting and indenting means therefor, as well as means for quickly and 'easily adjusting the depth of the indent sectional view of the machine taken on the line 1 1 of Fig. 3 is'a side elevational view of the fastener hopper and feed chute with parts brokenaway.
Fig. 4 is a fragmentary enlarged sectional view similar to Fig. 1 showing a somewhat advanced position of the driver. Fig. 5 is a vertical sectional view of Fig. 4.
Fig. 6 is 'a view similar to Fig. 4 of the driver, indenter and anvil 'showing the position of the parts during the compacting' of the `casing end and the beginning of the setting of the fastener. Y u
Fig. 7 is a similar view showing the fastener end edges brought together and the fastener rbent into a ring.
Fig. 8 is a similar view showing the Vfastener indented.
Fig. 9 is a sectional view of therfastener in the ringlike stage of the application thereof shown in Fig. 7.
Fig. 10 is a similar view of the indented fastener.
Fig. 11 is a fragmentary elevational view of a casing showing the end edges of the fastener.
Fig. 12 is a similar view showing the indent. V
Fig. 13 is an elevational view of the preferred form of an initially U-shaped fastener operated on by the machine.
Fig. 14 is a side elevational view thereof partly in section. v y
Figf'lS is a fragmentary side elevational view of the dial for indicating the adjustment of the depth of the ,indent in the fastener made by the machine.
The machine is intended to operate preferably upo the initially U-shaped ribbed sheet metal fastener 16 (Figs. 13-14)` a supply of which is inserted into a suitable hop-per which stacks the fasteners in a chute and feeds them to a driver. Said fastener has spaced apart legs 17 and 18 diverging toward the respective end edges 19 and 20 thereof. Each of said end edges is yliat and square, lying in a plane perpendicular to both faces of its leg. The .driver of the machine operates to bring said edges into pressed abutting relation (Figs. 9 and l0) to form a cylindrical ring around and out of Contact with the compactedcasing end, the ring having subustantially uninterrupted continuous inner and outer surfaces across said end edges. All other edges of the fastener, including the ribs, vare rounded to avoid pressing into, pinching or cutting fragilecasing material. After the formation ofthe ring, the indenter of the machine indents the fastener on the side opposite the abutting end edges. -By adjusting the depth of the indent 21 (Figs. l0 and 12) the machine can operate effectively and safely on casingsy made of cellulose or other materials which are easily damaged, or made of paper, cloth, polyethylene, fiber or any of the other materials customarily used to hold such food products as fresh or smoked meats including hams, calas, Canadian bacon, or grease including lard, butter, margarine or the like, or poultry, cheese, fruit and vegetables.
The machine will now be described in detail.
On the relatively wide raised platform 22 forming the top of a box-like support, is fixed the anvil support 23 carrying the anvil which has the anvil cavity 24 therein. The cavity has a relatively wide mouth and outwardly converging sides 25 joined by the cylindrical surface 26. To receive the ribs 27, 28 of the fastener 16 during the setting operation, the anvil is 'provided with upright slots 29, 29a (Fig. 2). A horizontal extension 30 on the anvil suppofrt provides a xed guide on which slides the horizontally reciprocating frame 31.
Cooperating'm'eans are provided on the fixed anvil support 23 and thereciprocating frame 31 to compact the casing end portion 32 and then to advance and bend the fastener. Said end portion, as is usual in the sealing or'tying of food casings, is iirst reduced quite substantially in diameter by twisting or pleating to compress it before it is inserted into the machine. Thereafter it is inserted through the opening 33 to the bottom edge 34 of said opening as formed by the projecting part 35 (Fig. l) of each of the spaced apart side plates 36, 37 fastened to the opposite parallel faces of the anvil support (Fig. 2). forming the opening 33 each has 'a lower concave portion 38 and an upper convex portion 39 overhanging the portion 38 and part of the bottom 34. Cooperating with the fixed plates 36, 37 are the similar parallel spaced apart movable plates or plate-like extensions 40, 41 on the sliding frame 31. The upper part of the end edge of each plate 40, 41 is convex and overhangs the lower adjacent concave part 43. At the lower part of each of the plates `40 and 41 is the forward or outward projection, the upper horizontal edge 42 of which is coplanar with the bottom 34 of the opening 33 between the fixed and movable plates when said plates are separated.
The inner edges of the ixed plates aora-vez As shown in Figs. 4-8, the upper parts 44 of the movable plates overlap the respective upper parts 39 of the fixed plates 36, 37 in the most forward or advanced position of the frame 31, while the edges 34 -and t2 form a support of substantial area for the casing V.end portion. In said Vadvanced position, the concave parts 38 and 43 are brought toward each other with the end portion lof the ycasing therebetween. Said parts compact the 'casing end to the required density and maintain 1t in its compacted condition, as bestseen in Fig. 6, before the fastener is applied thereto.
A horizon-tal groove 46 is made in the relatively thick forward part 45 of the frame 31, in'which slides the fastener driver soon to be described, while the frame itself slides on the xed extension 36 of the anvil support 23. To reciprocate the fram-e together with its side plates, a link 47 is pivoted at one end 48 to the rear end of the frame (Fig. 1) and is pivoted at its other end to the lever 49 pivoted at 5t) to the channel S1 secured to the under face of the platform 22. At its lower end, the lever carries lthe roller 52 adapted to be engaged by the reciprocating piston rod 53 of the air cylinder 54. As said rod moves rearwardly, it pushes the roller 52 `toward the right as viewed in Fig. 1, rotating the lever' e9 in a counter clockwise direction and drawing the link 47 and the frame 31 toward the left until the end portion of the piston rod has passed the roller, Whereupon the frame is locked in its thus advanced position until the piston rod is retracted. In said position, the casing end portion 4is co-mpacted and held compacted.
Simultaneously, a fastener Vis advanced toward the left Vinto a position (Fig. 6) part way around and out of contact with Vthe casing end but ready to be bent completely thereabout into the form of a ring. The advance A of the fastener is accomplished by the driver 60 reciproeating 'horizontally in the groove 46 of and relatively to the frame 31. A suitable cover plate 6 1 secured to the 4open side of =t-he frame (Fig. 5) retains the driver in .its groove and permits access thereto when removed. The forward or left end of the driver is shaped concavely to fit the arcuate end portion of the fastener and is suitably slotted to receive and to fit the ribs of the fastener deposited by the chute 62 in the groove 46 in front of the driver. Said chute is arranged sufficiently behind the opening 33 to permit said opening to be sub- .stantially closed by the overlapping plates 36, 40 and 37, 41, thereby' to compact the casing before the fastener reaches the casing end. Since the height of the concave parts 38 and 43 of the plates is less than the leastwidth of the space 63 between the legs 17, 18 of the fastener, I
the fastener does not touch the casing end until the ends of the fastener legs engage and are bent to a material extentby the converging sides 25 of the anvil cavity 24. During the final part of the advance of the driver, the fastener legs follow the cylindrical surface 26 of the anvil cavity and are bent into corresponding cylindrical form (Fig. 7) with `the flat and squared end edges 19 and 20 thereof firmly pressed together and held in tight fitting abutting relation7 thereby to provide concentric and substantially continuous and uninterrupted smooth cylindrical inner and outer surfaces on the resulting loose ring 64 around the casting end.
The ring 64 is of course ineffective to maintain the casing end compacted and sealed, for which reason the ring is indented and thereby brought into firmly pressed immovable engagement with the compacted casing end to seal the casing. The means for indenting the ring comprises the indenter 65 mounted for a limitedl reciprocation within and relatively to the driver 6i), but recprocating as a unit therewith prior to the formation of the ring. The indenter is operated by the rack 66 (Fig. l) secured thereto and meshing with the pinion 67 provided with the lnon-radial slot 68 therein. Arranged to enter the slot and to engage the edge 69 thereofV is the roller 70 suitably mounted at an intermediate point of the piston rod 53 and rotating the pinion in a counterclo-ckwise direction on the rearward movement of the piston rod. The pinion drives the rack and the indenter forwardly or to the left as viewed in Fig. l. Through the medium of the spring 71, which is arranged around the indenter and which engages the rear end of the driver 6i), said driver is moved toward the left with the indenter as la unit, the spring being strong enough to insure such movement until the fastener is formed into the ring `64 bythe driver.
Since the driver moves a greater distance than that required for the compacting of the casing end by the plates of the frame 31, the compacting operation is substantially completed before the ring forming operation, the frame 31, therack and the pinion moving as required for that purpose. However, after the movements of the frame and driver have been completed and the end edges 19 and 20 of the fastener brought together, the force required to move the ydriver against the resistance to Vdeformation of the ring 64 is greater than the resistance of the spring 71. Consequently, the indenter continues to move forwardly relatively to the driver and the frame, against said ring, thereby compressing the spring and forming the indent 21 between the ribs of the fastener at .a point opposite the abutting end edges 19, 2i?.
The depth of the indent depends on the size of the compacted casing end within the loose ring 64. Means are therefore provided to adjust the effective stroke of the indenter to determine such depth. Said means cornprises the rotatable cylindrical cam`75 (Fig. l) on the shaft 76 and serving as a stop to limit the travel of the piston rod rearwardly thereby limiting the forward move ment of the indenter into the ring. A visible dial 77 on the shaft 76 (Fig. 15) and cooperating `scale indicate the adjusted position of the cam and the depthvof the resulting indent. The maximum movement lof the indenter relatively to the driver is determined by the pin 78 (Fig. 4l) secured in and arranged transversely ofthe Slot 79 in the indenter and carried by the driver. On the retraction of the piston rod Within the air cylinder, the roller 52 is released by the rod to free the lever 49 to rotate in a clockwise direction toward the initial position thereof. The second roller 70 engages the forward edge of the slot 68 of the pinion and rotates the pinion in a clockwise direction until it leaves the slot.v During the initial part of the forward movement ofthe piston rod and the rack, the compressed spring 71 is permitted to expand and to move the indenter toward'the right. When the indenter engages the pin 78, the indenter "and" driver move together until the head of the adjusting screw 80, projecting from the rear end of the indenter, strikes the frame 31. Then the frame moves with the indenter and driver as a unit toward the right until the piston rod is completely retracted or the roller 70 leaves the pinion slot. Obviously, movement of the frame swings the lever 49 back into its initial position ready for the repetition of the operation.
An important advantage of the roller-slot operation of the pinion is the increasing pressure on the indenter and on the fastener during the indenting operation. In other words, the deeper the indent, the more pressure is exerted by the indenter to bend the initially arcuate end of the fastener into a reverse curve. Such increasing pressure is attainedl as the roller moves rearwardly and exerts a force horizontally against the edge of the pinion slot, the circumferential component of which force increases until the roller is below the center of the pinion.
The means for feeding fasteners tothe driver will now be described. The fasteners are supplied to the xed hopper 81 within which is arranged the fixed inclined guide rod 82 adapted to fit theinside surface of the fastener. The fixed llpuight chute 62 extends upwardly toward the under sidey of the guide rod, the lower end edgevof whichl is in vsufficiently spaced relation to the'adjacent hopper wall to permit the lowermost fastener of the row on the rod-tozslid'e off the rodinto the open top of the chute-if otherwise permitted to do so. However, the last fastener is not permitted to drop directly into the chute. Simple means are provided to force the fastener to turn by gravity into the proper position to be stacked and fed for drivingby the driver. As best seen in Fig. 4,
said means comprises the plate, lip or projection 84 extending from the wall 85 of the chute and slightly overhanging the top opening of the chute. The lip is of suffrcient width to engage andto obstruct the directfall into the chute of the end edge portion as 19 of the leg as 17v of the last fastener as the latter leaves the rod 82. As shown in Fig. 4, the other leg 18 of the fastener, being in the open chute and unsupported, falls further further into the chute and the fastener pivots about the edge 19 of the leg 17 as a fulcrum on the lip 84. The fastener consequently turns through an` angle of about 90 into the position shown wherein its longitudinal axis is horizontal, the temporarily obstructed leg leaving thelipfduring the turn. The bottom fastener falls out of the chute into the adjacent opening 85 in the frame 31 and into the groove 46 of the frame in front of the retracted driver as shown in Fig. 1.
A yieldable bevelled pin 86 serves to insure the maintenance of the longitudinal axis of the fastener horizontal or parallel to the sides of the groove 46. Said pin is provided with a conical head which, in the retractedlor rearward position of the driver (Fig. l) projects into the groove 46 into the path of the arcuate end portion of the fastener whereby said portion rests on the apex of the pin head in a proper driving position. As the driver advances to the position shown in Fig. 4, the pin is depressed out of the way againstthe action of its spring 87 which raises the pin again after the setting operation hasbeen completed and the driver has been retracted to a point behind the pin.
To agitate the fasteners within the hopper so that a sufcient number fall on to and stay on the guide rod, the exhaust blast-from the air cylinder is utilized. The exhaust is controlled by the relief port of the four-way valve 90 which port is connected by the pipe 91- (Fig. 2) to the bottom of the hopper. At each reciprocation of the piston of the air cylinder the blast blows the fasteners upwardly and a certain number fall on the guide rod in the positions shown in Fig. 3. Air is supplied to and exhausted from the forward side of the piston through the pipe 92 which is alternately connectable tothe supply port and to the `relief port of the valve 90 by Ia suitable manually operable handle or lever not shown and operating the valve. Similarly, the pipe 93 alternately connects the rear side of the piston -to the supply port and to te relief port, while the pipe 94 supplies air under pressure to the valve 90.
It will now be seen that the machine is simple and reliable, that it is capable of compacting, tying and sealing the crimped end portions of casings of various materials and sizes without danger of damage to the casing and by a simple adjustment `and that the intended purposes of the invention have been adequately attained.
While a certain specific form of the invention has herein been shown and described, various obvious changes may be made therein without departing from the spirit of the invention defined by the appended claims.
1. In a machine for compacting the end portion of a flexible casing and for applying to said end portion a U-shaped fastener having a pair of legs joined by an arcuate connecting portion, an anvil having a cavity therein, the walls of the cavity comprising an uninterrupted cylindrical surface joining a pair of converging at surfaces, means to compact said end portion at a point in inward spaced relation to the cavity walls, means to advance the fastener into the cavity and to cooperate with the surfaces of the cavity to bend the fastener into a closed ring around and in outward spaced relation to the compacted end portionv of the casing and with the end edges of the legs in pressed abutting contact, said advanc-I ing means'comprising a driver, and an indenter slidable within and projectable out of the driver and against the connecting portion of the fastener to indent said portion.
2. The machine of claim l, means for feeding fasteners to the driver Ycomprising a hopper, means for agitatingV the fasteners in the hopper, a rod for aligning the fasteners in a row, a chute communicating with the hopper and adjacent the rod, and means for turning the fasteners as the fasteners leave the rod and enter the chute.
3. In a machine `for applying a fastener to a casing, means for compacting the end portion of a casing, means for advancing a U-shaped fastener having legs each ending in a flat edge to a position wherein the legs are around and in outward and forward spaced relation to the compacted casing end, fixed anvil means cooperating with the advancing means for bending the fastener into a closed ring around the casing end and for bringing the fiat end edges of the legs into coplanar pressed contact with each other while the casing end at the front part thereof is in rearward spaced relation to the front part of the anvil, and means for indenting the ring concavcly outwardly at an area diametrically opposite the kcoplanar end edges to secure the fastener in tight contact with the compacted casing end.
4. In a machine for applying a fastener to a casing, means for compacting the end portion ofa casing, means for advancing a U-shaped fastener having legs each ending in a flat edge to a position around `and in outward spaced relation to the compacted casing end and for bending the fastener into a closed ring Iaround the casing end by bringing flat end edges of the legs into pressed abutting relation, and means for indenting the ring to secure the fastener in tight contact with the compacted casing end, the compacting means comprising a frame having a longitudinal groove therein for the reception of the fastener and having spaced apart side plates, and a fixed anvil support having spaced apart side platesv arranged to be overlapped by the side plates of the frame on the advance of the frame, the plates being shaped to receive the end portion of the casing therebetween on the retraction of the frame.
5. The machine of claim 4, the fastener advancing means comprising a driver carried by the frame yand slidable in the groove thereof, and the indenting means comprising an indenter carried by and slidable in the driver.
6. In a machine for applying a fastener to a casing, means for compacting the end portion of a casing, means for advancing a U-shaped fastener having legs each ending in a flat edge to a position around :and in out- Ward spaced relation to the compacted casing end and for bending the fastener into a closed ring around the casing end by bringing flat end edges of the legs into pressed abutting relation, and means for indenting the ring to secure the fastener in tight contact with the compacted casing end, =a fastener hopper, a chute leading from the hopper to the fastener advancing means, means in the hopper for aligning fasteners in 'a row, means for turning the leading fastener of the row in the hopper about the end edge of one leg as a pivot and for restraining the movement of said one leg as the fastener leaves the aligning means thereby permitting the fastener to turn and to drop by gravity out of the hopper and into the chute in a predetermined position.
7. In a machine for Kapplying a fastener to a casing, means for compacting the end portion of a casing, means for advancing a U-shapedy fastener having legs each ending in a flat edge to a position around and in outward spaced relation to the compacted casing end and for bending the fastener into a closed ring around the casing end by bringing at end edges of the legs into pressed abutting relation, and means for indenting the ring to secure the fastener in tight contact with the compacted casing end, a fastener hopper, the fastener advancing means including a compressed air cylinder` agravar having ya reciprocating piston rod, and also including a fastener driver carried by and reciprocating with the cornpacting means, means operatively connecting the piston rod to the driver, and means responsive to air exhausted from the cylinder for intermittently agitating the fasteners in the hopper.
8. In a machine for applying a fastener to a casing, a hopper for independent and loose U-shaped fasteners each having a pair of legs, a hollowv chute extending within the hopper and having a passage therein for the reception of a row of aligned contacting fasteners, means for guiding the fastenersr in a row toward the chute, fastener-leg-obstructing means at the top of the chute to engage and halt one leg only of the leading fastener of the row on the guiding means thereby to turn the fastener as the fastener leaves the guiding means and drops into the chute, means for advancing a fastener from the bottom of the chute, and means for first bending the fastener into a completely closed and uninterrupted circular ring around the compacted end portion of a casing and for then indenting the ring convexly inwardly atan area opposite the ends of the legs.
9. The machine of claim 8, and means for compacting the casing end including a reciprocating frame and transversely spaced apart plates carried by the frame, the
` fastener bending and indenting means being carried by and slidable in the frame.
l0. In a machine for applying a fastener to a casing, means for compacting the crimped end portion of a casing including a fixed part and a reciprocating part, means for feeding a fastener into the reciprocating part and in front of a driver, a driver reciprocating in andv relatively to the reciprocating part, the fixed part having lan anvil cavity therein cooperating with the driver to bend the fastener into a ring around and in outward spaced relation to the compacted casing end, and an indenter reciproctaing in and relatively to the driver sufficiently to indent the ring and thereby to secure the fastener immovably around the compacted casing end.
11. The machine of claim l0, air controlled means for operating the compacting means, the driver and the indenter, a hopper for fasteners, and au air conduit between the air-controlled operating means and the hopper t agitate the fasteners by an air blast through the conduit, the fastener feeding means including a fixed chute leading from the hopper toward the driver.
l2. In a machine for applying a fastener to a casing, means for compacting the end portion of a crimped casing, means for arranging U-shaped fasteners in a row and for feeding the fasteners, means for advancing a fastener and for bending the fastener into a tightly closed ring around and in spaced relation to the compacted end portion of the casing and for maintaining the ring closed, means for indenting the ring sufficiently to secure the fastener against movement on the compacted end portion, the compacting means comprising a reciprocating frame and a cooperating member, the fastener bending means comprising a driver carried by and reciprocating in the frame, the indenting means comprising an indenter carried by and reciprocating in the driver, and a spring interposed between the indenter and the driver to cause operation of the driver and the indenter as a unit until the resistance of the spring is overcome.
13. In a machine for applying a fastener to a casing, means for compacting the end portion of a crimped casing, means for arranging U-shaped fasteners in a row and for feeding the fasteners, means for advancing a fastener and for bending the fastener into a tightly closed ring around and in spaced relation to the compacted end portion of the casing and for maintaining the ring closed, means for indenting the ring suiciently to secure the fastener against movement on the compacted end portion, the compacting means and the bending means being movable relatively to each other, and means to adjust the amount of the relative movement of the compacting means and the bending means. i
14. The machine of claim 13, the indenting meanscomprising a reciprocating indenter having a convex end edge, and means to adjust the depth of the indent made by the indenting means.
15. Inl a machine for applying a U-shaped sheet metal fastener to the crimped end portion of a fragile casing, a fixed anvil having a U-shaped cavity therein comprising outwardly diverging sides joined at the inners thereof by an arcuate end wall, a driver having a concavely rounded end wall, means for reciprocating the driver toward and from the anvil thereby to bend the diverging sides of a fastener into the arcuate form of the arcuate end wall of the anvil, and an indenter having a convexly rounded end edge reciprocating in and relatively to the driver.
16. In a machine for applying a fastener to a fragile casing, means for compacting theend portion of the casing, meansfor advancing around the casing a U-shaped fastener having a pair of legs joined by a connecting arcuate bend, fixed anvil means engaging the end portions of the legs of the fastener on the advance of the fastener to bendy and close said end portions of the legs into pressed end to end contact and into the form of the anvil bend to form a smooth closed circular ring, means for exerting increasing indenting pressure on the arcuate bend of the fastener to indent a circumferential middle part of said connecting bend between the side edges of the connecting bend convexly inwardly, and means for reciprocating the compacting means as well as the fastener vadvancing means and the indenting means inthe same direction and as a unit for part of each forward and backward stroke thereof.
17. In a machine for applying a fastener to a casing, means for compacting the crimped end portion of a fragile casing, means for feeding a U-shaped fastener having legs joined by a bend, to a position around and out of contact with the compacted end portion, means including a fixed anvil for bending the legs into arcuate form and for closing the fastener into a completely closed circular ring in which the end edges of the legs meet smoothly, means for reciprocating the compacting means and the fastener closing means, and means for applying gradually increasing pressure to the closed ring to indent the bend of the fastener convexly inwardly and to move the compacted casing toward the meeting ends of the closed legs.
18. In a machine for applying a fastener to a casing, means for compacting the end portion of a crimped casing, means for arranging U-shaped fasteners having a pair of legs and a leg-connecting part, in a row and for feeding the fasteners, means movable relatively to the cornpacting means for advancing a fastener and for bending the fastener into a tightly closed circular ring around and in spaced relation at the forward part thereof to the compacted end portion of the casing and` for maintaining the ring closed and with the end edges of the legs thereof in contact with each other, and means for indenting the leg-connecting part of the fastener convexly inwardly substantially to eliminate the initial space between the closed ring and such compacted end portion for securing the fastener against movement on the compacted end portion.
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