Tray And Pad Interleaving Apparatus

Abstract

In accordance with this invention, single absorbent pads are interleaved between adjacent food packaging trays of the type used in packing and displaying chickens and the like. The trays are in nested condition and are moved along an upwardly inclined first guide chute and in a substantially vertical position to an interleaving station. The trays leaving the interleaving station are in nested condition and are moved along a downwardly inclined second guide chute to provide a substantially V-shaped opening at the interleaving station and between the leading tray of the approaching group and the trailing tray of the leaving group of trays so that the upper ends of these trays are separated and moved out of their nesting relationship. An absorbent pad is fed in a substantially vertical position and into the V-shaped opening prior to the movement of each tray through the interleaving station so that an absorbent pad is interleaved between the successive trays leaving the interleaving station.

Description

The present invention relates generally to an apparatus for interleaving a single absorbent pad between adjacent trays and more particularly to such an apparatus for interleaving single absorbent pads between adjacent trays of the type which are normally used in the packaging and displaying of food products, such as chickens and the like.

Certain food products, such as chickens, are packaged for display and sale in molded trays with an absorbent pad in the bottom to take up liquid which drains from the product. It has been the practice for the person forming the package to select a tray, place an absorbent pad in the lower portion thereof, than place the food product on the pad in the tray and enclose the entire package with a transparent, heat-sealable film. The placement of the absorbent pad in the tray requires an extra operating step, thereby increasing the time required to package the products.

Accordingly, it is an object of the present invention to provide an apparatus for automatically interleaving a single absorbent pad between adjacent trays so that a stack of trays is provided with an absorbent pad already placed in the position in each tray.

This object is accomplished in accordance with the present invention by providing an apparatus for feeding the trays in a substantially vertical position and past an interleaving station. The group of trays approaching the interleaving station are in nested condition and inclined upwardly while the group of trays leaving the interleaving station are in nested condition and inclined downwardly to provide a substantially V-shaped opening at the interleaving station and between the two groups of trays so that the upper ends of the trays at each side of the V-shaped opening are separated and moved out of their nesting relationship. Means is provided for successively moving the leading tray of the approaching group across the V-shaped opening at the interleaving station to become the trailing tray of the leaving group. Absorbent pad feeding means is provided to operate in timed relationship to the movement of the trays across the V-shaped opening and to feed a pad into the V-shaped opening prior to the successive movement of each leading tray of the approaching group to become the trailing tray of the leaving group so that an absorbent pad is interleaved between the successive trays leaving the interleaving station.

The apparatus preferably includes a single drive motor and an interleaving station at each side of the apparatus. Both interleaving stations are normally operated by the single motor and either of the stations may be disengaged without stopping the operation of the other interleaving station.

Other objects and advantages of the invention will appear as the description proceeds, when taken in connection with the accompanying drawings, in which --

FIG. 1 is a front elevational view of the interleaving apparatus and illustrating substantially identical interleaving stations at opposite sides of the apparatus;

FIG. 2 is a side elevational view of the apparatus, looking at the right-hand side of FIG. 1;

FIG. 3 is an enlarged fragmentary elevational view of the central portion of FIG. 2 and illustrating the manner in which the groups of approaching and leaving trays provide a substantially V-shaped opening at the interleaving station;

FIG. 4 is an enlarged fragmentary vertical sectional view being taken substantially along the line 4--4 in FIG. 1;

FIG. 5 is a vertical sectional view taken substantially along the line 5--5 in FIG. 4;

FIG. 6 is an enlarged fragmentary elevational view of the pad feeding mechanism;

FIG. 7 is a vertical sectional view taken substantially along the line 7--7 in FIG. 6;

FIG. 8 is a sectional plan view of the drive mechanism, being taken substantially along the line 8--8 in FIG. 2;

FIG. 9 is a fragmentary plan view looking downwardly on the V-shaped opening formed between the group of trays approaching the interleaving station and the group of trays leaving the interleaving station, being taken substantially along the line 9--9 in FIG. 3; and

FIG. 10 is an isometric view of one of the packaging trays with an absorbent pad being positioned therein.

The apparatus illustrated includes a pair of identical interleaving stations at opposite sides and these interleaving stations are selectively operable from a single drive motor 10 (FIGS. 2 and 8) which is fixed on a rectangular base plate 11 supported on a rectangular frame 12. The motor 10 is drivingly connected to the input side of a gear reduction unit 13 by means of a drive chain 14. Drive chains 15, 15' are driven from opposite output sides of the gear reduction unit 13 and in turn are drivingly connected to electric clutches 16, 16' which are supported on respective drive shafts 17, 17', supported for rotation on the base plate 11.

Since the interleaving stations at each side of the apparatus are identical, only the interleaving station on the right-hand side of FIG. 1 will be described in detail and the corresponding parts of the interleaving station on the left-hand side of FIG. 1 will bear like reference characters with the prime notation added. A vertical support plate 20 is fixed at its lower end to the frame 12 and its upper end is connected to the upper end of the corresponding support plate 20' by means of cross plates 21.

Means is provided for supporting and moving the nested trays, indicated at T, along in a substantially vertical position and past the interleaving station and includes a first tray guiding chute, broadly indicated at 22. The chute 22 supports and directs an approaching group of substantially vertically disposed and nested trays T along an upwardly inclined path of travel to an interleaving station, to be presently described. As illustrated in FIG. 10, the trays T have upstanding sides and the bottom portion of one tray fits within and is "nested" in the upstanding sides of the next tray (FIGS. 2 and 3) when they are moved along in a substantially vertical position.

The first tray guiding chute 22 includes a pair of spaced apart lower support rails 23 (FIG. 5), on which the lower edges of the trays T are supported, and a pair of opposed side rails 24 which maintain the trays moving in a straight line path toward the interleaving station. The tray guiding chute 22 is supported on shafts 25, 26 (FIG. 2) which are respectively supported on the machine frame 12 and the support plate 20.

A second tray guiding chute, broadly indicated at 30, guides the interleaved pads and trays away from the interleaving station and is inclined downwardly therefrom. The chute 30 includes a pair of spaced apart downwardly extending lower support rails 31 (FIG. 1) for engaging and supporting the lower edges of the trays leaving the interleaving station and a pair of spaced apart side rails 32 for maintaining the interleaved pads and trays in a straight line path as they leave the interleaving station. The second chute 30 is supported on support shafts 33, 34 which are respectively supported by a support bracket 35 fixed on the frame 12 and the support plate 20 (FIG. 2).

Means is provided for moving the group of nested trays T upwardly along the chute 22 and comprises a pressure plate 36 (FIG. 3) which is supported on the medial portion of a shaft 37. One end of the shaft 37 is provided with a roller 38 which is adapted to move along on top of the side rail 24 and the other end of the shaft 37 is fixed in a slide bracket 40 which is supported for sliding movement along a guide shaft 41. A cable 42 is connected to the slide bracket 40 and extends partially around the lower side of a guide pulley 43 (FIG. 4) which is supported on the support plate 20, and over a guide pulley 44 which is supported for rotation on a bracket 45 fixed on the cross plate 21. The opposite end of the cable 42 is attached to a weight 46 which hangs downwardly inside of a guide tube 47, fixed on the front of the frame 12. Thus, the weight 46 supplies pressure on the plate 36 to urge the vertically nested groups of trays T upwardly along the inclined first tray guiding chute 22 toward the upper end thereof and toward the interleaving station.

Means is provided for successively moving the leading tray of the approaching group, supported in the first guide chute 22, to become the trailing tray of the leaving group, supported in the second tray guide chute 30, and comprises a notched rocking shaft 48 (FIG. 3) positioned between the first and second tray guide chutes 22, 30. As illustrated in FIG. 3, the rocking shaft 48 engages the lower edge of the leading tray of the approaching group of trays and cooperates in moving the same from nested condition with the approaching group to nested condition with the leaving group, in a manner to be presently described. Rotatable release means, in the form of a rotating shaft 50 having a notched sleeve thereon, is positioned at the upper edge of the leading tray of the approaching group and is operable to maintain the leading tray in an inclined and nest position. The shaft 50 is rotated in timed relationship to rocking movement of the rocking shaft 48 to release the upper edge of the leading tray as the lower edge is moved by the rocking shaft 48.

The means for successively moving the leading tray of the approaching group to become the trailing tray of the leaving group also includes resiliently supported fingers 52 (FIG. 9) which are positioned intermediate the upper and lower ends of the trays and at opposite sides thereof. The fingers 52 are supported for limited pivoting movement and are normally urged to the position shown in FIG. 9 by torsion springs 52a. The fingers 52 are supported on the upper ends of corresponding operating arms 53. The lower ends of the arms 53 are fixed on a rocking drive shaft 54 which is supported on the support plate 20. The inner end of the rocking drive shaft 54 (FIG. 4) has a slotted lever arm 55 fixed thereto. A drive pin 56 is fixed in off-center relationship on a wheel 57 which is fixed on one end of a stub shaft 58, supported for rotation in the support plate 20. A gear 59 is supported on the shaft 58 and meshes with a gear 60 (FIG. 3) which is fixed on a stub shaft 62, rotatably supported in the support plate 20. Rotation is imparted to the gears 60, 59 and respective shafts 62, 58 by means of a drive chain 63 which is driven from a sprocket on the lower drive shaft 17 (FIG. 3).

A crank wheel 64 (FIG. 4) is fixed on the inner end of the shaft 62 and has the lower end of a connecting rod 65 connected thereto in off-center relationship. The upper end of the rod 65 is connected to the outer end of a crank arm 66 which is fixed on the inner end of the notched rock shaft 48. Thus, the drive from the main drive shaft 17 is transmitted through the chain 63 and gears 60, 59 (FIG. 3) to drive wheels 57, 64 (FIG. 4) and to impart reciprocation to the notched rock shaft 48 and the fingers 52 in timed relationship to each other.

Another drive chain 70 is rotated by the main drive shaft 17 (FIG. 8) and extends upwardly therefrom and surrounds an upper sprocket 71 (FIGS. 4 and 5) which is fixed on one end of a drive shaft 72. The drive shaft 72 is rotatably supported in a support bracket 73 which forms the means for supporting the stack of horizontally positioned absorbent pads, in a manner to be presently described. A drive sprocket 75 (FIGS. 4 and 5) is rotated by the drive chain 70 and is fixed on the rotatable release shaft 50. The shaft 50 is supported for rotation in a bracket 76 fixed on the plate member 20.

Stacked absorbent pads P are supported at their rear lower portion on a support plate 80 (FIG. 3) and are maintained in vertical alignment by a feed chute including a pair of front rails 81 and a pair of side rails 82 extending upwardly in front and on one side of the stack of pads P. An adjustable side rod 83 extends upwardly along the opposite side of the pads P and is supported on the front rails 81. Spaced apart feed wheels 84, 85 (FIG. 7) are fixed on the drive shaft 72 and on opposite sides of a cam wheel 86, maintained in a nonrotating position by a support bracket 87 (FIG. 6). The feed wheel 84 is provided with a serrated pad feed shoe 90 (FIGS. 6 and 7) which is pivotally supported at one end as at 91 and has an operating roller 92 supported thereon for engagement with the cam 86. A tension spring 93 maintains the roller 92 in contact with the cam 86 as rotation is imparted to the feed wheels 84, 85 by means of the drive chain 70. As the feed wheel 84 rotates, in a counterclockwise direction in FIG. 6, the feed shoe 90 is raised by the cam wheel 86 as it approaches the stack of pads P to engage the forward end of the lowermost pad and remove it from the stack. The upper end of a guide plate 95 is supported on the lower end of the pad feed chute and is spaced from and extends downwardly by the feed wheel 84 to guide the pad P into a vertical position as it is moved around by the feed shoe 90. As the pad P reaches a substantially vertical position, the roller 92 moves onto the low part of the cam 86 and moves out of gripping engagement with the pad to release the same so that it will fall into the V-shaped opening provided at the interleaving station and between the leading tray of the approaching group and the trailing tray of the leaving group.

As illustrated in FIG. 3, the lower end of the guide plate 95 supports the forward end of a tray support and guide, in the form of a leather apron 96 which rests by gravity on the upper edges of the group of leaving trays being moved downwardly along the second chute 30. A resilient locking finger 97 is also supported at the lower end of the guide plate 95 and is adapted to engage the rear upper edge of the trailing tray of the leaving group so that it is maintained in the position shown in FIG. 3 after being moved to this position by the resilient fingers 52.

METHOD OF OPERATION

To operate the interleaving apparatus, the operator loads the first chute 22 with nested trays T and loads the upper pad chute with absorbent pads P at opposite sides of the machine. If it is desired to operate both sides of the machine at the same time, the electric clutches 16, 16' (FIG. 8) are activated so that both main drive shafts 17, 17' rotate. The leading tray T of the approaching group is maintained in an inclined and nested position, as shown in FIG. 3 by the notched rocking shaft 48 and the upper release shaft 50. A single tray may be positioned in the chute 30 and inclined as shown in FIG. 3 to provide the trailing tray of the leaving group and to form a V-shaped opening between the separated upper ends of the trays approaching the interleaving station and the trays leaving the interleaving station.

The cam wheels 84, 85 are rotated so that the shoe 90 removes the lowermost pad P and deposits it in the V-shaped opening at the interleaving station and in a substantially vertical position. The operating arms 53 swing in a clockwise direction so that the fingers 52 are moved behind the opposite side edges of the leading tray. The rock shaft 48 is reciprocated as the upper release shaft 50 is rotated and the fingers 52 move the leading tray forwardly so that it becomes the trailing tray of the leaving group. The trailing tray is held in this position as the upper edge is engaged and held in position by the locking finger 97.

This operation continues with a pad being deposited in the V-shaped opening just prior to each successive movement of a tray from the nested position with the approaching group to the nested position with the leaving group so that a pad P is interleaved between each of the nested trays T as they move down the second chute 30. The pressure plate 36 continuously applies pressure on the nested trays of the approaching group so that the next tray is moved into position against the rock shaft 48 and the upper release shaft 50 each time the leading tray is removed from the approaching group. The operator removes groups of the trays from the lower end of the second chute 30 and stacks them in a horizontal position so that each tray is provided with a pad P, as illustrated in FIG. 10, and the stack of trays is ready to have food products packaged therein, such as chickens and the like, so that any liquid from the food product will be absorbed by the pad P in the lower portion of the tray T.

In accordance with the method of the present invention, a line of nested trays is moved along and past an interleaving station where absorbent pads are successively inserted between the trays as they are successively moved out of nesting relationship. After the pads are inserted, the trays are successively moved back into nested relationship. The nested trays are moved along a substantially horizontal path of travel with the trays approaching the interleaving station moving along an upwardly inclined path and the trays leaving the interleaving station moving along a downwardly inclined path to provide a substantially V-shaped opening at the interleaving station with the lower ends of the leading tray and the leaving tray remaining in at least partially nested condition. Absorbent pads are successively dropped into the opening and their downward movement is limited by the nested lower ends of the trays at the interleaving station.

The apparatus of the present invention is adapted to operate at a high rate of speed and may accommodate a large number of trays and pads for interleaving. If it is necessary to stop the interleaving operation at one side of the machine, the other side may continue to operate. Since the clutches 16, 16' may be operated to selectively drive the main drive shafts 17, 17', either side of the machine may continue to operate while the other side is stopped.

In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

That which is claimed is:

1. An apparatus for interleaving absorbent pads between adjacent trays, said apparatus comprising

a. means for moving a line of nested trays along a predetermined path of travel and past an interleaving station,

b. means for successively moving the leading tray out of nesting relationship with the remaining trays at the interleaving station to form an opening therebetween,

c. means for successively inserting absorbent pads into the opening formed between the trays, and

d. means operating in timed relationship to said means (b) for successively returning the trays to nested relationship as they leave the interleaving station and with the absorbent pads therebetween.

2. An apparatus for interleaving absorbent pads between adjacent trays, said apparatus comprising

a. means for supporting and moving the trays along in a substantially vertical position and past an interleaving station, said support means being inclined upwardly to the interleaving station and being inclined downwardly from the interleaving station so that the group of trays approaching and the group of trays leaving the interleaving station are inclined in opposite directions to provide a substantially V-shaped opening at the interleaving station and between the two groups of trays,

b. means for successively moving the leading tray of the approaching group to become the trailing tray of the leaving group,

c. means supporting a stack of horizontally positioned absorbent pads above the interleaving station, and

d. means operating in timed relationship to said means (b) for successively removing the lower pad of the stack and positioning the same in a substantially vertical position in the V-shaped opening prior to the successive movement of each leading tray of the approaching group to become the trailing tray of the leaving group so that an absorbent pad is interleaved between successive trays leaving the interleaving station.

3. Apparatus according to claim 2 wherein each of said means (a) through (d) is provided on each side of said apparatus to simultaneously interleave absorbent pads between successive trays moving along in parallel rows of trays at each side of said apparatus, and including a single drive motor supplying motion to each of said means at each side of said apparatus.

4. Apparatus according to claim 3 including clutch means interposed between said single drive motor and said interleaving means at each side of said apparatus, said clutch means each being independently operable so that the interleaving operation at one side of the apparatus may be stopped while the interleaving operation at the other side of the apparatus may continue.

5. An apparatus according to claim 2 wherein said means (a) comprises a first tray guiding chute inclined upwardly to the interleaving station, and a second tray guiding chute spaced from said first chute and inclined downwardly from the interleaving station.

6. An apparatus according to claim 5 wherein said means (b) comprises a notched rocking shaft positioned between said first and second tray guiding chutes and engaging the lower edges of successive trays for moving the same from the approaching group to the leaving group, rotatable release means positioned at the upper edge of the leading tray of the approaching group and being operable to maintain the leading tray in inclined position, said release means being rotated in timed relationship to rocking movement of said rocking shaft to release the upper edge of the leading tray as the lower edge is moved by said rocking shaft, resiliently supported fingers engageable with opposite sides of the leading tray and intermediate the upper and lower ends, and means for reciprocating said fingers in timed relationship to rotation of said release means and to movement of said rocking shaft, said fingers being operable to successively move the leading tray of the approaching group of trays across the interleaving station to become the trailing tray of the leaving group.

7. An apparatus according to claim 6 wherein said means for reciprocating said fingers includes an operating arm supported adjacent each side of the interleaving station and supporting said fingers on the upper ends thereof, a rocking drive shaft supporting the lower ends of said operating arms, a lever arm fixed at one end on said rocking drive shaft and having a slotted lower end, a drive pin in the slotted lower end of said lever arm, and a rotating wheel supporting said drive pin in off-center relationship to impart reciprocation to said lever arm with rotation of said wheel.

8. An apparatus according to claim 6 including locking means engageable with the upper rear edge portion of the trailing tray of the leaving group for holding the upper portion in position when the leading tray of the approaching group is moved through the interleaving station to become the trailing tray of the leaving group.

9. Apparatus according to claim 2 wherein said means (c) includes an open frame substantially vertically extending chute adapted to maintain absorbent pads in substantially vertical alignment above the interleaving station, and a support plate extending across the lower rear portion of said chute for supporting the lowermost pad of the stack and leaving the forward end free.

10. Apparatus according to claim 9 wherein said means (d) comprises a pair of spaced apart feed wheels supported for rotation beneath said chute, a guide plate spaced from said feed wheels and fixed at its upper end on the lower portion of said vertically extending chute, and pad gripping means supported on said feed wheels for frictionally engaging and removing the lowermost pad from the stack and directing it vertically into the V-shaped opening between the two groups of trays at the interleaving station.

11. Apparatus according to claim 10 wherein said pad gripping means comprises a serrated feed shoe supported between said feed wheels a cam wheel fixed between said feed wheels and being operable to raise said feed shoe beyond the periphery of said feed wheels as said feed shoe passes beneath said stack of absorbent pads for engaging and withdrawing the lowermost absorbent pad from the stack, said cam wheel being operable to withdraw said feed shoe between said feed wheels as the absorbent pad is moved to a substantially vertical position to release the same.

12. A method of interleaving absorbent pads between adjacent trays comprising the steps of

a. moving a line of nested trays along a predetermined path of travel and past an interleaving station,

b. successively moving the leading tray out of nesting relationship with the remaining trays at the interleaving station to form an opening therebetween,

c. successively inserting absorbent pads into the opening formed between the trays, and

d. successively returning the trays to nested relationship as they leave the interleaving station and with the abosrbent pads therebetween.

13. A method according to claim 12 including moving one side of the leading tray out of nesting relationship while maintaining the other side of the leading tray in at least partially nested condition to form a substantially V-shaped opening therebetween.

14. A method according to claim 13 wherein the line of nested trays are moved along a substantially horizontal path of travel, the upper side of the leading tray is moved out of nested condition and the lower side of the leading tray remains in nested condition with the next tray, and the absorbent pad is dropped in a substantially vertical position into the opening so that the lower end of the absorbent pad engages the nested lower portions of the adjacent trays to limit downward movement of the absorbent pad.

15. A method of interleaving absorbent pads between adjacent trays comprising the steps of

a. moving a group of nested trays along an upwardly inclined path with the trays being perpendicular to the upwardly inclined path,

b. successively moving the upper end of the leading tray of the upwardly inclined group of trays out of nested position with the next tray and to a position perpendicular to a downwardly inclined path to provide a substantially V-shaped opening between the moved tray and the remaining trays of the group moving along the upwardly inclined path and to form a group of nested trays moving along the downwardly inclined path, and

c. positioning an absorbent pad in a substantially vertical position in the V-shaped opening following each successive movement of the leading tray of the upwardly inclined group of trays to interleave a single absorbent pad between the nested trays moving along the downwardly inclined path.