US3870166A

US3870166A - Stacking and transferring unit

Info

Publication number: US3870166A
Application number: US213886A
Authority: US
Inventors: Iii Herbert G Tull
Original assignee: Hoerner Waldorf Corp
Current assignee: Stone Container Corp; Hoerner Waldorf Corp
Priority date: 1970-09-21
Filing date: 1971-12-30
Publication date: 1975-03-11
Anticipated expiration: 1992-03-11

Abstract

Generally rectangular objects are delivered to an elevator platform and lifted past a series of supporting plates which pivot to let them pass, butt swing down to prevent them from lowering with the elevator platform. When a stack is complete, it is transferred laterally into a hopper. Retractable means are provided to engage and support the trailing edges of the objects during the transfer operation.

Description

United States Patent [191 Tull, III

[ Mar. 11, 1975 1 STACKING AND TRANSFERRING UNIT [75] Inventor: Herbert G. Tull, III, Charlottesvill [7 3] Assignee: Hoerner Waldorf Corporation, St.

Paul, Minn.

[22] Filed: Dec. 30, 1971 [211 Appl. No.: 213,886

Related U.S. Application Data [63] Continuation-impart of Ser. No. 73,967, Sept. 21,

1970, Pat. No. 3,701,314.

521 U.S. c1 214/6 BA, 271/212 [51] Int. Cl. B65g 57/30 [58] Field of Search 214/6 BA, 6 H, 6 DK, 6 B; 271/212 [56] References Cited UNITED STATES PATENTS 3,013,369 12/1961 Wilson et a1. 214/6 BA 3,124,059 3/1964 Labombarde 214/6 DK Groll 214/6 DK 3,451,562 6/1969 Sjostrom 214/6 BA 3,486,636 12/1969 Stroup 214/6 BA 3,519,144 7/1970 Calistrat 214/6 BA 3,545,367 12/1970 Smith et al.. 214/6 BA 3,622,017 11/1971 Mueller 214/6 BA 3,659,728 5/1972 Reinecke 214/6 H Primary Examiner-Robert G. Sheridan Assistant Examiner-Leslie .1. Paperner Attorney, Agent, or Firm-Robert M. Dunning; Jerry F. Best [57] ABSTRACT Generally rectangular objects are delivered to an elevator platform and lifted past a series of supporting plates which pivot to let them pass, butt swing down to prevent them from lowering with the elevator platform. When a stack is complete, it is transferred laterally into a hopper. Retractable means are provided to engage and support the trailing edges of the objects during the transfer operation.

2 Claims, 8 Drawing Figures PATENTED'MRI H915 3', 870, 1 66 sum 1 of 3 INVENTOR HERBERT G. 721M. 122' BY iZ lm mQng ATTORNEY PATENTEDHARI 1 I975 sum 2 o 3 INVENTOR HERBERT G. TULL ZZZ' BY 831mg ATTORNEY PATENTED 1 I975 3, 870.156

'sum 3 a; 3

i4 INVENTOR HERBERT 6. 7211.1. 112' u ja j w g ATTORNEY STACKING AND TRANSFERRING UNIT BACKGROUND OF THE INVENTION Various means have been provided for stacking items one above another. Devices such as container sealers apply adhesive to the closure flaps of the containers and then stack the closed containers one above the other to hold the flaps closed until the adhesive has set. Means are usually provided for pushing the uppermost container off the stack and onto a suitable slide or conveyor.

For example, in Pat. No. 2,997,830 issued Aug. 29, 1961, to Iver L. Nelson, corrugated folders are closed, and are stacked one above another. Lugs are provided for engaging beneath opposite sides of the lowermost folder for holding the folders from dropping in the stack. However, I do not know of any previous structure embodying the stacking features of the present invention.

SUMMARY OF THE INVENTION The present structure comprises a stacking apparatus capable of stacking and transferring material such as hands of bags or similar products which are relatively flexible. The present device receives hands of bags,

each hand including, for example, 25 bags in superimposed relation. Due to the fact the closed ends of the bags are substantially thicker ,than the open ends thereof, the groups or hands of bags are alternated so that the closed ends of alternate hands overlie the open ends of bags of the intermediate hands. This is accomplished by a collator which acts to collect a predetermined number of bags and turn them in one direction or another for delivery to the stacker. Obviously, such an apparatus is not necessary if the objects being stacked are of equal thickness throughout their area.

A feature of the present invention resides in the provision of pivotally mounted supporting plates designed to engage all four edges of the lowermost rectangular bag of each hand. This is desirable in view of the fact that the flexibility of the bags may otherwise cause them to sag sufficiently to pass between the supports if supported only on two opposite sides. These plates are normally horizontal, but swing upwardly as each hand of bags is raised by a suitable elevator means. When the elevator means is lowered, the edges of the bags rest upon the supporting plates and the bags are supported thereby on all four edges.

A further feature of the present invention resides in the provision of a means for supporting the rear edges of the stack of bags as the bags are transferred from stacking position to a suitable receiving hopper. The elevator which lifts the bags is raised to the level of the floor of the hopper and the stack is moved laterally into the hopper. It is desirable to lower the elevator during the time the bags are moving laterally into the hopper in order to speed up the operation of the apparatus and to permit the lowering of the elevator to receive another hand of bags. In order to support the trailing edge of the bags as they are moved, hook means are provided on the lower edge of the bag moving or transferring apparatus which engage beneath the trailing edge of the lowermost bag of the stack to hold the bags from dropping. Means are provided for normally retracting these hooks during the stacking operation, and automatically projecting the hooks beneath the bag stack as the transfer movement of the stack starts.

These and other object and novel features of the present invention will be more clearly and fully set forth in the following Specification and Claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view showing the end portion of the collator, the stacker, and hopper, showing the general arrangement of parts.

FIG. 2 is a perspective view of the end of the collator and intake end of the stacker.

FIG. 3 is a horizontal sectional view through the stacker, the position of the section being indicated by the line 3-3 of FIG. 2.

FIG. 4 is a sectional view through the lower portion of the stacker, the position of the section being indicated by the line 44 of FIG. 3.

FIG. 5 is a view similar to FIG. 1 showing the stack being transferred to the hopper.

FIG. 6 is an enlarged vertical sectional view showing the stack being transferred into the hopper, and the elevator in lowered position.

FIG. 7 is a diagrammatic perspective view of the lower portion of the transfer mechanism in stack transferring position.

FIG. 8 is an enlarged sectional detail showing one of the hooks for supporting the trailing edge of the stack during the transfer thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION The transfer and stacking unit is indicated in general by the letter A. The unit A includes a frame which is indicated in general by the numeral 10 and includes supporting

legs

11 and 12 which form a part of the frame. Generally horizontal frame members 13 at the top of the legs 11 supports a conveyor chute 14 through which the hands of bags are pushed, the collator and the means for transferring the hands not being illustrated in the drawings. The hands of bags are illustrated in general by the number 15. Due to the fact that the bags are thicker at one end than at the other, the hands are alternated,'with the closed ends of the bags of alternate hands overlying the open ends of the bags of the intermediate hands.

An elevator platform which is indicated in general by the numeral 16 is diagrammatically shown in FIGS. 1, 4, 5 and 6 of the drawings. As shown in FIGS. 1 and 5, the elevator platform 16 is supported by a pair of generally L shaped legs 17 having horizontal arm portions 19 at their lower ends attached to vertical tubular slides 20. The slides 20 are slideably supported by slide rods 21 extending between a lug 22 on the frame leg 11. and the horizontal frame member 13 as indicated at 23. An arm 24 is pivotally connected at 25 to the upper end of a link 26, the lower end of which is connected at 27 to a lug 29 on a plate 30 connecting the ends 19 of the legs 17. Oscillation of the arm 24 about a pivot axis acts to raise and lower the supporting legs 17 and to raise and lower the elevator platform 16. The means for oscillating an arm such as 24 is well known, and not illustrated.

As indicated in FIG. 1, in the lowered position of the platforms 16, the platform is substantially coplanar with the bottom of the chute 14. As is indicated in FIG.

5 of the drawings, in the elevated position of the elevator 16, the top of the elevator is substantially coplanar with the lower plate 31 of a hopper 32. The hopper 32 is designed to accommodate the stack of bags. In actual practice, the hopper is pivotally supported in a manner illustrated in my previous application for patent which is referred to above. As the present application refers only to the stacking and transferring apparatus. the means of supporting the hopper is not disclosed in detail in the present application. The hopper supporting arm is indicated in FIGS. 4 and 6 of the drawings by the numeral 33.

The hopper 32 includes partial side plates such as 34 between which the stack is forced. As indicated in 2 and 3 of the drawings, a side plate 35 is also provided on the frame between which the bags are stacked. The trailing edges of the bags are also held in position during the stacking operation by a pair of transfer bars 36 which are held in spaced relation by a transverse bracket 37 and other means to be described. The bracket 37 is connected at each end to slides 39, each ofwhich is slideable in a horizontal generally U-shaped frame 40. The bracket 37 is moved horizontally by a piston rod 41 connected to a piston in the cylinder 42 mounted on the frame 10.

As indicated in FIGS. 2 and 3 of the drawings, the platform 16 includes a central plate 43 and a pair of side plates 44 connected in spaced parallel relation by connecting members 45. The reason for this arrangement is to provide slots in the upper surface of the platform for a purpose which will be later described. The collator chute 14 is provided with a pair of laterally extending wings 46 which act to support a pair of vertical angle brackets 47. A cross bar 49 is pivotally connected as indicated at 50 to the upper ends of the angle brackets 47. A pair of vertical mounting bars 51 extend downwardly from the cross bar 49, the upper ends of which are engageable with the transfer bars 36. Pivot blocks 52 are provided on the lower ends ofthe mounting bars 51. Stacking guides 53 extend downwardly from the blocks 52 and curve outwardly at their lower ends in order to assist in guiding the hands of the bags as they are elevated.

A bag support plate 54 is pivotally supported between the pivot blocks 52. The bag supporting plate 54 is held from movement in a clock-wise direction from the position indicated in FIG. 4 of the drawings by a suitable stop 55 or other such means. The bag supporting plate 54 is free to pivot in a counter clockwise direction toward vertical position so as to permit the bags to move upwardly.

A frame member 56 is supported beneath the lower plate 31 of the hopper. An L-shaped block 57 is mounted on each side of center of the hopper, the position of these blocks being indicated in FIG. 3 of the drawings. A bag supporting plate 59 is pivotally supported as indicated at 60 between the blocks 57, the plate 59 normally resting upon a cross bar 61 connecting the blocks 57. The bag supporting plate 59 is pivotal in a clockwise direction from the position shown in FIGS. 4 and 6 so as to permit bags to swing the bag supporting plates upwardly, but to hold the bags from moving downwardly with the elevator platform 16.

As indicated in FIG. 3 of the drawings, brackets 63 are fixedly supported in spaced opposed relation upon frame members 64 arranged on opposite sides of the elevator platform 16. These brackets 63 pivotally support bag supporting plates 65 as indicated at 66. The plates 65 normally rest upon the frame member 64 and are held in horizontal position thereby. However the plates 65 are free to pivot upwardly in the manner of the other

bag supporting plates

54 and 59.

The elevator platform 16 is of somewhat smaller dimensions than the bags, the outline size of the bags being indicated by the broken line 67 in FIG. 3. Ac cordingly, the hands of bags may be elevated by the platform 16, the bags pivoting the various bag supports upwardly to permit passage thereof. The platform 16 is reciprocated upwardly until it is substantially coplanar with the lower plate 31 of the hopper 32. As the platform 16 is lowered, the hands of bags are engaged by the various bag supporting plates so as to hold the bag in an elevated position. The platform 16 may then move downwardly to the dotted outline position in FIG. 4 of the drawings and as shown in full lines in FIG. 6 thereof. In this position they are adapted to receive another hand of bags. It is important to note in FIG. 4 of the drawings that the hands of bags 15 which are supported by the pivotal plates tend to sag downwardly at the center although the sag is insufficient to disengage the bags from the pivotal supporting plates. This sagging of the lowermost hands of the bags is of assistance to the operation of the apparatus as the bags rest upon the top of the hand being elevated and tend to hold the hands in vertical alignment. The tendency for the hands to shift in any direction is prevented by the engagement with the hand being lifted as is indicated in FIG. 4.

When a sufficient number of hands has been accumulated, transfer means is actuated to transfer the stack of bags into the hopper 32. When the stack is complete, fluid is directed to the cylinder 42 which moves the transfer bars 36 to the right as indicated in the drawings, forcing the hands of bags 15 into the hopper 32. The transfer operation is initiated while the elevator platform 16 is in an elevated position. Means are provided to support the trailing edges of the bags as they are transferred, and once the forward or leading edges of the bags are engaged by the bottom plate 31 of the hopper, the elevator platform 16 may move downwardly to receive another hand of bags.

With reference now to FIG. 8 of the drawings, the lower ends of the transfer bars 36 are provided with generally L-shaped notches 70. Hook elements 71 are pivotally supported as indicated at 72 to the transfer bars, the hook elements being urged in a counter clockwise direction by a suitable spring 73. The lower ends of the hook elements 71 are provided with hook projections 74 designed to extend beneath the lowermost bag of the lowermost hand. The rear surface 75 of each hook element 71 is normally flush with the rear edge 76 of the transfer bar 36.

As is indicated in FIG. 4 of the drawings, when the transfer bars 36 are in normal or in retracted position, the upper corner 77 of each hook element 71 has engaged the surface of a corresponding vertical mounting bar 51, and the hook element 71 has been swung into vertical position in the notch as is indicated in this Figure. However, as soon as the transfer bars 36 start into motion, the springs 73 expand and pivot the lower end of the hook elements beneath the trailing edges of the bags 15, as indicated in FIGS. 6 and 8 of the drawings. FIG. 7 indicates in perspective the position of the hook elements when the transfer bars are in movement.

The operation of the apparatus is believed evident from the foregoing explanation. The hands of bags are delivered from the collator chute l4 unto the elevator platform 16. The hands of bags are then elevated past the bag supporting plates, swinging these plates upwardly in order to pass by them. The elevator platform 16 then descends into position to pick up another hand of bags. The bags are supported by the bag supporting plates during the downward movement of the platform 16.

When the stack is completed, the transfer bars 36 are moved to the right to slide the stack of bags unto the hopper bottom plate 31. As the transfer bars start to move, the hook elements 71 swing beneath the trailing edges of the bags to support the bags during the remainder of the operation. The hook elements 71 are aligned with the space between the

platform plates

43 and 44 so that the hooks may move while the platform is still in elevated position or until the bags are forced sufficiently unto the operable bottom plate 31 to insure there movement into the hopper.

In accordance with the Patent Statutes, l have described the principles of construction and operation of my improvement in STACKING AND TRANSFER- RlNG APPARATUS; while I have endeavored to set forth the best embodiment thereof, I desire to have it understood that obvious changes may be made within the scope of the following Claims without departing from the spirit of my invention.

I claim: 1. A stacking apparatus for use in combination with generally flexible rectangular objects including:

an elevator platform, two pairs of supporting plates, the plates of each pair being in spaced parallel relation with the plates of one pair in substantially right angular relation to the plates of the other pair, said plates engaging all four edges of said objects,

means pivotally supporting each of said plates adjacent the outer edges thereof for movement from a generally horizontal position to an upwardly and inwardly inclined position, said platform being of proper dimensions to pass between said plates in horizontal position thereof,

guide means guiding the objects against said plates upon upward movement of said platform, pivoting said plates upwardly as they pass the plates, said plates swinging downward to horizontal position after the objects pass therebetween, whereby the flexible objects will sag downwardly near the central portions thereof,

means for reciprocating said platform,

transfer means engageable with a series of objects stacked upon said supporting plates to move said objects out of alignment with said elevator platform,

said transfer means including laterally spaced bars,

5 and including,

hook-shaped elements pivotally secured to the lower ends of said bars,

said elements, in one position, engaging beneath the trailing edges of said stacked objects during move- 10 ment thereof by said transfer means, and are retracted in a second position, means urging said hook-shaped elements toward said one position, and means holding said hook-shaped elements in said second position prior to movement of said transfer means.

2. A stacking apparatus for use in combination with generally flexible rectangular objects including a pair of supporting plates, said plates being in spaced parallel relation engaging opposite edges of said objects,

means pivotally supporting each of said plates adjacent the outer edges thereof for movement from a generally horizontal position to an upwardly and inwardly inclined position,

an elevator platform supported for vertical reciprocation,

said platform being of proper dimensions to pass between said plates in horizontal position thereof,

upward movement of said platform raising said objects against said plates, pivoting said plates upwardly as they pass the plates, said plates swinging downwardly to horizontal position after the objects pass therebetween,

said transfer means including laterally spaced bars.

and including,

hook-shaped elements pivotally secured to the lower ends of said bars,

said elements, in one position, engaging beneath the trailing edges of said stacked objects during movement thereof by said transfer means, and are retracted in a second position,

means urging said hook-shaped elements toward said one position, and

means holding said hook-shaped elements in said second position prior to movement of said transfer means.

Claims

1. A stacking apparatus for use in combination with generally flexible rectangular objects including: an elevator platform, two pairs of supporting plates, the plates of each pair being in spaced parallel relation with the plates of one pair in substantially right angular relation to the plates of the other pair, said plates engaging all four edges of said objects, means pivotally supporting each of said plates adjacent the outer edges thereof for movement from a generally horizontal position to an upwardly and inwardly inclined position, said platform being of proper dimensions to pass between said plates in horizontal position thereof, guide means guiding the objects against said plates upon upward movement of said platform, pivoting said plates upwardly as they pass the plates, said plates swinging downward to horizontal position after the objects pass therebetween, whereby the flexible objects will sag downwardly near the central portions thereof, means for reciprocating said platform, transfer means engageable with a series of objects stacked upon said supporting plates to move said objects out of alignment with said elevator platform, said transfer means including laterally spaced bars, and including, hook-shaped elements pivotally secured to the lower ends of said bars, said elements, in one position, engaging beneath the trailing edges of said stacked objects during movement thereof by said transfer means, and are retracted in a second position, means urging said hook-shaped elements toward said one position, and means holding said hook-shaped elements in said second position prior to movement of said transfer means.