US3557688A

US3557688A - Bundle-forming apparatus

Info

Publication number: US3557688A
Application number: US678955A
Authority: US
Inventors: Ellsworth A Hartbauer; Richard Shankel
Original assignee: Crown Zellerbach Corp
Current assignee: James River Corp of Nevada
Priority date: 1967-10-30
Filing date: 1967-10-30
Publication date: 1971-01-26
Anticipated expiration: 1988-01-26

Abstract

A machine for accumulating groups of collated paper grocery bags into bundles, compressing the bundles, and transferring each compressed bundle into a banding mechanism which wraps a securing band about the bundle. The machine includes an accumulator section which receives successive groups of collated bags constituting the discharge from a collating mechanism and organizes such groups into bundles, it also includes a compression section for squeezing each bundle to reduce the plane-to-plane dimension thereof, and it further includes a transfer section which receives the compressed bundles from the compression section and displaces each compressed bundle along an arcuate path and into a banding mechanism.

Description

United States Patent [72] inventors Ellsworth A. Hartbauer Concord; Richard Shankel. Antioch. Calif. [21] Appl. No. 678,955 [22 Filed Oct. 30. 1967 [451 Patented Jan. 26.1971 [73] Assignee Crown Zellerbach Corporation San Francisco, Calif. a corporation of Nevada [54] BUNDLE-FORMING APPARATUS 21 Claims, 22 Drawing Figs.

[52] US. Cl 100/218, 53/124. 93/93, 100/3. 100/264. 198/106, 214/7 [51] Int. Cl B30b 15/32, B65b 13/02 [50] Field of Search 100/215. 218, 264. 35. 2. 3; 93/931. 93.2, 93.3; 53/124; 198/106. 34; 214/7 [56] References Cited UNITED STATES PATENTS 2,729,151 l/1956 Evers 93/93 Primary ExaminerPeter Feldman Attorney-Stanley Bialos ABSTRACT: A machine for accumulating groups of collated paper grocery bags into bundles, compressing the bundles, and transferring each compressed bundle into a banding mechanism which wraps a securing band about the bundle. The machine includes an accumulator section which receives successive groups of collated bags constituting the discharge from a collating mechanism and organizes such groups into bundles. it also includes a compression section for squeezing each bundle to reduce the plane-to-plane dimension thereof, and it further includes a transfer section which receives the compressed bundles from the compression section and displaces each compressed bundle along an arcuate path and into a banding mechanism.

PATENTEU mas l97| SHEET PATENTED JAN26 IHYI SHEET 0% OF 15 PATENTED JANZSIQII 3557 688 sum as or 16 irramviy PATENTEU JAN26 I971 sum as or 1 BM/t IrraeA/ PATENTEU JANZ s zen sum as or 1a [3% 4r roe/vi) PATENTEUJANZBIQH 3557.688

SHEET 10UF16 PATENTEU JAN26 I9?! 8; 557.688

sum 13 uF 16 ja /a,

irraeA PATENIEU JANZSISYI SHEET 1a or 16 BUNDLE-FORMING APPARATUS This invention relates to apparatus for arranging articles into bundles, and it relates more particularly to bundle-form ing apparatus operative to accumulate into bundles articles such as paper grocery bags and the like, which maybe collated into groups or hands, and to transfer the accumulated bundles into a banding machine.

The particular embodiments of the invention considered in detail herein are especially adapted for use in processing paper grocery bags which have been collated into groups or hands, each hand of which constitutes a predetermined number of bags which, by way of example, may be taken to be 50 bags. Bags collated into groups or hands of this character usually constitute the discharge of a bag-collating machine, and for information, a specific example of such a machine is disclosed in pending application Ser. No. 494,742, filed Oct. I1, 1965, now U.S. Pat. No. 3,404,609, dated Oct. 8, I968. The bundle-forming apparatus is operative to accept the group-by-group discharge from such collating machine and to accumulate or collect such groups into bundles, each bundle of which constitutes a predetermined number of groups which, by way of example, may be taken to be lO-bag groups (500 bags).

After a plurality of bag groups have been so accumulated into a bundle, the bundle is compressed to squeeze air therefrom and thereby reduce the plane-to-plane dimension thereof. Thereafter, the bundles are advanced by the apparatus one by one into a banding machine which places a wrapper or securing band about each bundle to maintain the bags therein in a confined or bundled state. Evidently, the bagcollating machine and banding machine must have their operations synchronously related and, accordingly, the bun tile-forming apparatus has its operational cycle timed to each since it constitutes an intermediate apparatus with respect to these two machines.

Bundle-forming apparatus of the general type being considered herein has been known heretofore, and an object, among others, of the present invention is to provide an improved bundle-forming apparatus especially suited to processing bags at the relatively high rates of delivery provided by a collating machine of the type noted. The improved bundle-forming apparatus constituting'the present invention includes a bundle-forming section which collects into bundles the bag hands or groups continuously discharged by the bag collating machine, it further includes a compression section in which the collected bundles are reduced in dimension, and it still further includes a transfer section which advances the compressed bundles one by one into a banding machine whereat each bundle is equipped with a wrapper. As concerns specific objects and advantages of the invention, many will become apparent as the various sections of the apparatus are considered in detail hereinafter in the specification.

DRAWING DESCRIPTION Embodiments of the invention are illustrated in the accompanying drawings, in which:

FiG. i is a diagrammatic side view in elevation of apparatus embodying the invention;

H6. 2 is an enlarged, broken top plan view taken along the plane 2-22 of FIG. ll;

FIG. 3 is a broken longitudinal sectional view taken through the center of the apparatus along the vertical plane 3-3 of FIG. 2;

H6. 4 is a broken longitudinal sectional view taken along the generally horizontal plane M of FIG. 3;

FiG. 5 is a broken longitudinal sectional view taken along the line 5-5 of FIG. 2; I

F iG. 6 is a broken transverse sectional view taken along the plane 5-!) of FIG. 3;

FIG. 7 is a broken transverse sectional view taken along the plane '7--7 of FIG. 3;

FIG. 8 is a broken vertical sectional view illustrating the shield or shutter used in association with the optical counter;

FIG. 9 is a broken side view in elevation of the compression and transfer sections of the apparatus;

FIG. I0 is an end view in elevation of the compression and transfer sections shown in FIG. 9, the view being taken from the left looking toward the right as the sections are depicted in FIG. 9;

FIG. III is an enlarged top plan view of the compression and transfer sections taken along the plane 11-11 of FIG. I;

FIG. 12 is a transverse sectional view taken along the plane l212 of FIG. 11-,

FIG. 13 is a broken transverse sectional view taken along the plane 13-l3 of FIG. 12;

FIG. I4 is a broken longitudinal sectional view taken along the plane ltd-l4 of FIG. I1;

FIG. 15 is a diagrammatic side view in elevation somewhat similar to FIG. I and illustrating the location of the various switches used to control a cycle of operation of the apparatus;

FIG. 16 is a schematic circuit diagram illustrating the control circuitry of the apparatus;

FIG. 17 is a broken horizontal sectional view taken through the center of a modified embodiment of the apparatus, the view being generally similar to that of FIG. 3;

FIG. I8 is an enlarged broken top plan view of the infeed end portion of the accumulator section of the modified apparatus illustrated in FIG. I7;

FIG. I9 is a broken top plan view illustrating the mergence of the discharge end of the accumulator section and infecd end of the compression section of the modified apparatus;

FIG. 20 is an enlarged broken side view in elevation of the compression section illustrated in FIG. 19 of the modified apparatus, the orientation of the compression section being shifted to a horizontal position for illustrative convenience;

FIG. 21 is an enlarged vertical sectional view taken along the line 21-21 of FIG. 20; and

FIG. 22 is an enlarged vertical sectional view taken along the line 22-22 of FIG. 20.

GENERAL DESCRIPTION The bundle-forming apparatus is operative to accumulate or collect into bundles of predetermined number, articles delivered thereto in quantities less than such number. In the case of the articles being paper grocery bags, they will be collated so that a bundle of uniform dimensions can be formed; and as a specific example, such bags may be delivered to the apparatus in groups or hands by collating mechanism of the group-processing type as disclosed in pending application, Ser. No. 494,742, filed Oct. II, 1965, now U.S. Pat. No. 3,404,609, dated Oct. 8, I968. Such collator mechanism is indicated generally in FIG. 1 by the brokenline block designated in its entirety with the numeral 20, and it is opera' tive to orient bags into groups each of which comprises a predetermined number of bags, 50 for example, with the bottom ends thereof all disposed in the same direction. Alternate groups are oriented with the bag ends in opposite directions so that several groups may be brought into compressed juxtaposition to form a bundle of substantially uniform dimensions. The apparatus of the present invention is operative to accumulate such collated groups, compress or form the same into bundles constituted of a predetermined number of bag groups, 10 groups or hands of 50 bags each for example, and to transfer each compressed bundle into a banding machine operative to wrap a securing band about the bundle. The banding machine may be completely conventional as, for example, the banding press sold by the American Manufacturing Company of Portland, Ore, under the designation Banding Press, Model APB-3." The banding machine is also illustrated diagrammatically in FIG. I by the broken-line block designated with the numeral 2ll.

The bundle-forming apparatus is disposed intermediate the group collator 20 and bander 2I and is designated in its entirety in the drawings with the numeral 22. For convenience of description, the apparatus may be taken to comprise three separate sections which will be considered in the functional order thereof; and such sections include an accumulator section 2.3, a compression section 24, and a transfer section 25 operative between the full-line and broken-line positions shown in FIG. l to transfer or displace a bundle of compressed groups from the compression section 24 and into the bander 2i, A plurality of bag groups at are shown in FlG. l in association with the apparatus 22, and it will be noted that successive groups as disposed along the accumulator section 23 and along the compression section 24 are oppositely oriented so that in one instance the closed bottom ends ofthe bags face outwardly and in the other instance the open upper ends thereof face outwardly.

Successive bag groups 203 are delivered to the accumulator section 23 in spaced-apart relation, and are maintained in such spaced relation while being advanced by the accumulator section 23 to the compression section 2d. The spacing between groups is utilized in controlling the automatic functioning of the apparatus in that each bundle displaced by the transfer section 25 to the bander 21 is intended to be constituted of a fixed or predetermined number of bag groups. in this respect, counter mechanism 27 in the form of an optically actuated system is employed to count the number of groups advanced by the accumulator section 2.3 into the compression section 24 and to initiate a cycle of operation following the advancement of each such bundle-forming predetermined number of groups into the compression section. in each cycle of operation, a compressed bundle of bag groups is displaced by the transfer section 25 into the bander 2i, and after the bander has processed such bundle, the transfer mechanism 25 returns to its starting position which is depicted in full lines in H0. ll.

ACQUMULATQR SECTKON in describing the details of the accumulator section, reference will be made in particular to FlGS. ll through d; and referring thereto the accumulator section 23% is seen to include frame structure in the form of transversely spaced

sideplates

28 and 29 which are adapted to be supported upon a suitable pad or floor structure and are tied together in part by a plurality of longitudinally spaced and transversely extending bars Trill, 31 and 32. Disposed between the

frame plates

28 and 29 and extending longitudinally of the apparatus is a track which supports the bag groups as thereon. Such track, as seen best in H65. 4 and 5, is defined by a pair of transversely spaced and substantially parallel rails 33 and 3d secured to and carried by the frame bars 3b and fil Adjacent the entrance end of the accumulator section, the rails 33 and 341 have respectively bolted thereto extensions 33' and 34' which define a transition between the aforementioned group collator 2% and the accumulator section 23 so as to blend the mergence of the horizontally disposed collator track with the angularly oriented accumulator track, which in the particular apparatus being considered has an angular disposition of approximately from the horizontal.

The bag groups as are delivered onto the track defined by the

rails

33 and 3 in spaced-apart relation and are advanced along the track by conveyor structure in the form of a pair of endless chains respectively disposed along opposite sides of the track and each equipped with lugs or fingers which enter the space between adjacent bag groups and engage the forwardrnost group to push the same forwardly. The conveyor structure is symmetrical as respects the centerline of the apparatus; and accordingly, the mechanism on one side is a substantial duplication of that on the other side. Consequently, in the following description, only the conveyor components on one side of the apparatus will be considered in detail, it being understood that the description applies equally to the duplicates of such components; and for purposes of identifying the respectively corresponding parts, the suffixes a and I; will be appropriately added to the parts numerals.

Considering the conveyor component disposed along the rail 33, the endless chain thereof is denoted with the numeral 35 and is entrained at its forward end about a drive sprocket so and at its rear end about an idler sprocket 37. Each chain 35, as shown best in H6. 5, rides between the sprockets 3n and 37 in a pair of stationary guide and support structures Elf and 39 which at one end are bolted to an upwardly extending post lt) bolted to the frame bar 3t), and intermediate the ends thereof are bolted to a support block 41 secured to the frame bar 33 and extending upwardly therefrom. Evidently, the support structures and 3 9 terminate adjacent each end a spaced distance from the sprockets as and 37 so as to provide adequate clearance therefor. Also, while the support structures 33 and 39 may be fabricated in any suitable manner, in the form shown they are comprised of three generally planar plates configurated so as to define a channel adjacent the upper ends thereof which receives the associated chain 35 therein and supports the same in a horizontal sense. The three plates forming each support may be affixed to each other as by means of the aforementioned bolts which secure each entity to the support members an and ll.

Secured to each chain 35 at spaced-apart locations therealong are a plurality of lugs or flights 42. each of which comprises an inverted, Ushapcd bracket 43 bolted or otherwise secured at one end to the chain and extending laterally outwardly therefrom and further comprises a pusher finger 44 affixed to the bracket adjacent its opposite end. Each linger 441 is oriented in a generally vertical plane so as to define a firm engagement with a group of bags to be advanced thereby, which bags are also disposed in a generally vertical direction. As illustrated in HQ. 5, the fingers 44 incline downwardly and outwardly with respect to the associated chain 35 which, as illustrated in FIG. 3, enables such fingers to assist transition of the bag groups 26 from the horizontally disposed discharge end of the collator 20 onto the inclined track of the accumulator apparatus 23.

The conveyor chains 35 are continuously driven in timed relation with the associated collator mechanism, and in the bundle-forming apparatus being illustrated and described, the timed relationship is enforced upon the conveyor chains by driving the same directly from the collator mechanism. ln this respect and referring especially to H65. 3 and 4, the drive assembly for the conveyor chains includes a main shaft 45 which is transversely disposed with respect to the apparatus and is journaled for rotation adjacent its opposite ends in suitable bearing structure (not shown) mounted on the frame plates 23 and 29). Mounted upon the shaft 45 so as to rotatably drive the same is a sprocket as having an endless drive chain 47 entrained thereabout. Such chain is adapted to be driven by suitable sprocket structure provided by the collator apparatus 2d, and since the interconnection of such apparatus may be conventional, such drive sprocket is not illustrated.

Mounted upon the drive shaft 45 inwardly of the frame plates 2% and 29 are a pair of sprockets lda and dflb respectively associated with the chains 35a and 35b, and such sprockets are affixed to the shaft &5 so as to be driven thereby. Each of the sprockets %3 has entrained thereabout an endless drive chain 49 which is also entrained about a sprocket 50 mounted upon a stub shaft 51 journaled for rotation in bearing structure provided by the spaced legs of a generally U-shaped bracket 52 bolted to the frame bar 30. Each stub shaft 51 is equipped intermediate the ends thereof with a vertically disposed bevel gear 53a which drivingly meshes with a horizontally disposed bevel gear 54 secured to a vertically oriented shaft 555 rotatably supported in a bearing block as fixedly secured to the aforementioned post so. At its upper end, the shaft 55 is equipped with the aforementioned drive sprocket 36 which is keyed or otherwise fixed thereto to constrain the same against relative rotation.

The associated sprocket 37 is mounted upon a stationary shaft or post 57 (lFlG. 55) carried by and extending upwardly from a support plate supported for adjustment by a mounting block 5% confined between the associated support guides 38 and 39. The plate 58 serves as a tension adjustment for the associated chain 35 and-can be selectively displaced longitudinally with respect to the apparatus by an adjustment screw 60 and then affixed in any position of adjustment by a clamping screw 61. Each of the endless drive chains 49 is also provided with a tension device in the form of a takeup sprocket 62, as shown in FIGS. 3 and 9. Such takeup sprocket 62 is mounted upon a bracket 63 pivotally supported on the associated stub shaft 5l bolted to the associated bracket 52. An elongated arcuate slot formed in the bracket 63 permits angular displacements thereof about the axis defined by the shaft 51 so as to selectively establish the tension imparted to the associated chain 49.

Evidently, the main drive shaft 45 is continuously driven because of its interconnection with the collator and necessarily then is driven in an enforced time relationship therewith. The shaft 45 in turn continuously drives the

chains

49a and 49b which drive the respectively associated sprockets 36a and 36b through the aforementioned sprockets 50, shaft 51, bevel gears 53 and 54, and shaft 55. Therefore, the conveyor chains 35a and 35b are continuously driven in an enforced time relationship, and it will be noted especially in FIG. 2 that the flights or lugs 42a and 42b are arranged in aligned pairs so that each bundle 26 is engaged along the opposite end portions thereof by a pair of flights 42a and 42b so as to be advanced along the track defined by the

rails

33 and 34. As is most evident in FIG. 9, each of the sprockets 50 is angularly adjustable with respect to the associated stub shaft 51 by mounting structure which includes an elongated slot and capscrew arrangement of substantially conventional character, which arrangement permits manual tailoring of the apparatus to enforce a condition of precise alignment as between the paired conveyor lugs or flights 42a and 42b respectively carried by the endless chains 35a and 35b.

Considering FIG. 2 in particular, each group 26 is advanced into the accumulator section 23 by mechanism comprising a part of the aforementioned collator and the details of such mechanism may be obtained by reference to the aforementioned Pat. application, Ser. No. 494,742. However, for illustrative purposes, such mechanism is shown in FIG. 2 in largely diagrammatic form as a pair of fingers or holders 64a and 6411 which are cyclically reciprocable longitudinally so as to displace each group of bags in the direction of the arrows into a forwardmost position such that the trailing or rearmost bag in such group is disposed generally along the line 65. At such location of a group 26, the conveyor chains 35a and 3512 are able to advance a pair of lugs or flights 42a and 42b into engagement with the rearmost bag in such group and thereby initiate continuous movement of the group toward the discharge end of the accumulator apparatus.

To confine each group 26 of bags in a transverse sense and support and guide the same along the ends thereof, a pair of guides 66a and 66b are provided adjacent the infeed end of the apparatus and are spaced apart by a distance substantially equivalent to the length of the bags comprising a group 26 thereof. The guides may diverge outwardly along the entrance ends thereof to form an enlarged mouth through which the bag groups are advanced. The guides 66 are respectively carried by the adjustable plates 58, and in this respect may be secured to the associated sprocket shafts or posts 57 as by means of capscrews which are received within threaded openings provided therefor in such shafts or posts.

As the groups 26 are advanced along the

rails

33 and 34 from the infeed end of the accumulator section to the discharge end thereof, the bags in each group have a vibratory motion imparted thereto both in vertical and transverse directions so as to effect uniformity in the disposition of the bags in each group thereof. That is to say, the intent is to have the bags in each group thereof accurately aligned from end to end and from edge to edge so that a bundle of uniform dimensions can be formed from a plurality of such bag groups; and such alignment of the bags can be effected by imparting motion thereto of a character which will cause relative movement between the bags until a condition of alignment thereof is realized.

In this respect and considering first the mechanism by which a horizontally oriented vibratory motion is imparted to the bags, it is seen especially in FIGS. 2 and 5 that a pair of joggers or vibration-imparting side rails 67a and 67b are disposed generally along the

rails

33 and 34 and at an elevation slightly thereabove. Each of the side rails is substantially U-shapcd in cross section with the base thereof being vertically disposed to define the sidewalls along which the bag groups are moved. Each side rail 67 adjacent the forward end thereof is pivotally supported on a post 68 secured to a mounting plate 69 carried by the associated chain guides 38 and 39 in underlying relation therewith. Clearly, such pivotal supports for the side rails 67 are located adjacent the discharge end of the accumulator section (i.e., adjacent the drive sprockets 36) and the side rails are angularly displaceable toward and away from each other about the axes respectively provided by the posts 68.

Although the angle of displacement of the side rails remains the same along the entire lengths thereof, the stroke or magnitude of the arc transversed by the side rails becomes progressively greater as the distance from the pivot axes thereof increases. Thus, and by way of example, if the side rails 67 are displaced inwardly through an angle of a few degrees, the corresponding transverse movement of the rails would be substantially zero at the pivot axes thereof but could increase to a significant amount adjacent the infeed end of the apparatus, depending of course on the precise length of the side rails.

Displacements are imparted to each of the side rails 67 by cam structure in the form of a sawtooth-type cam 70 secured to the side rails and extending therealong adjacent the infeed end of the accumulator section. The precise length of each cam 70 and the depth or magnitude and pitch or frequency of the cam will depend upon any particular installation, and the cam structure illustrated has three rises and four falls along the length thereof. Each cam 70 is actuated by engagement therewith of one of a plurality of cam followers 71 respectively carried by the aforementioned lugs or flights 42. Thus, as each flight traverses the arcuate path of travel defined by the associated sprocket 37, the cam follower 71 carried by such lug is advanced into engagement with the cam 70 and displaces the same in lateral directions as the cam follower rides therealong.

The cam 70 is resiliently biased outwardly by a helical spring 72 (FIG. 5) which at one end thereof is secured to the associated side rail and at its other end is anchored to a clip 73 affixed to the outer chain 38. The spring is effective to enforce engagement between the cam and a cam follower moving therealong and enables each such cam follower to displace the cam inwardly against the biasing force imparted thereto by the spring. Evidently, the vibratory motion imparted to each of the side rails 67 is intermittent in the sense that the flights or lugs 42 are spaced apart and are moved in sequence one after another into engagement with the cam. it will be apparent that as each group 26 moves through the accumulator section 23, the transverse dimension through which the group passes diminishes progressively toward the terminal ends of the side rails 67 so that when each group is adjacent such terminal ends, the bags should be closely aligned in a transverse sense.

As indicated hereinbefore, the bag groups also have a vertically oriented vibratory motion imparted thereto by a pair of vibration-imparting joggers 74a and 74b which extend generally along the

rails

33 and 34 exteriorly thereof. The joggers 74 are pivotally secured by posts 750 and 75b to the respectively associated rails adjacent the forward ends thereof to enable the joggers to be swung upwardly and downwardly about the axes respectively defined by such posts 75. Vibratory displacements are imparted to the joggers by cam structure which includes a generally square-shaped cam 76 (FIG. 3) mounted upon the drive shaft 45 so as to be rotatably driven thereby.

Claims

1. In bundle-forming apparatus, a compression section having an infeed end through which successive groups of collated bags or the like are transferred for collection and formation along said section into a compressed bundle, said compression section comprising longitudinally extending rail structure defining a track along which such successive groups are collected, a transfer device adjacent the infeed end of said compression section and being provided with pusher finger structure movable into engagement with each successive group arriving at such infeed end and being displaceable along said track for advancing each successive group therealong, and movement-limiting stop means provided adjacent the terminal end of said compression section forwardly of such infeed end thereof and defining a limiting position for the advancement of such groups along said track, whereby at cyclically repetitive times occurring whenever the aggregate number of groups being collected along said track is sufficient to define a bundle, the bundle-completing group then being advanced by said transfer device together with the groups forwardly thereof will be compressed between said stop means and pusher finger structure, drive mechanism for said transfer device to cyclically and repetitively displace the same along said track, and clamping means for maintaining such bundle in the compressed condition thereof following withdrawal therefrom of said pusher finger structure.

2. The bundle-forming apparatus of claim 1 and further comprising guide structure extending along said track for confining in transverse directions each such group being advanced along said track.

3. The bundle-forming apparatus of claim 1 in which the pusher finger structure of said transfer device is selectively movable between an extended group-engaging position and a retracted position remote from any such group, and further comprising motor means connected with said pusher finger structure and operable to enforce such movements of said pusher finger structure with respect thereto.

4. The bundle-forming apparatus of claim 3 in which said pusher finger structure comprises a pair of transversely spaced pusher fingers each movable in enforced synchronism by said motor means between the aforesaid extended and retracted positions.

5. The bundle-forming apparatus of claim 1 in which said movement-limiting stop means includes a stop selectively movable between an extended position in which it projects above said track for engagement by such group and a retracted position below said track and further includes clamping fingers also selectively movable between a group-engaging extended position above said track and a retracted position therebelow, and in which said apparatus further comprises motor means for selectively displacing said stop and clamping fingers in timed relation between the extended and retracted positions thereof.

6. The bundle-forming apparatus of claim 1 in which said compression section further comprises a trolley mechanism movable along said track and having retaining finger structure selectively displaceable between an extended position in which it projects above said track for engagement by the leading bag in the forwardmost group and a retracted position below saId track, and motor means for selectively displacing said retaining finger structure between the extended and retracted positions thereof.

7. The bundle-forming apparatus of claim 6 in which said track is inclined upwardly toward the terminal end thereof, and in which said trolley mechanism is freely movable along said track and is gravity biased toward the infeed end of said compression section.

8. The bundle-forming apparatus of claim 7 in which said movement-limiting stop means includes clamping fingers selectively movable between a group-engaging extended position above said track and a retracted position therebelow, and motor means for selectively displacing said clamping finger between such positions thereof.

9. In bundle-forming apparatus, a compression section having an infeed end through which successive groups of collated bags or the like are transferred for collection and formation into a compressed bundle and a transfer section operative to displace each such compressed bundle into a banding mechanism or the like, said sections comprising a longitudinally extending rail structure defining a track along which successive groups transferred through such infeed end are collected, a transfer device adjacent the infeed end of such compression section and being provided with pusher finger structure movable into engagement with each successive group arriving at such infeed end and being displaceable along said track for advancing each successive group therealong, drive mechanism for said transfer device to cyclically and repetitively displace the same along said track, longitudinally extending transfer rails extending generally along the aforesaid rail structure and being adapted to remove therefrom a bundle collected therealong and to transfer such removed bundle from the bundle-receiving position of said transfer rails to a bundle-discharge position adjacent such banding mechanism, motor means for selectively moving said transfer rails between such positions thereof, a pair of clamping structures for confining such a bundle therebetween and being respectively disposed adjacent opposite end portions of said transfer section and movable with said transfer rails thereof between such bundle-engaging and bundle-dishcarge positions, and motor means for selectively displacing said clamping structures between an extended bundle-engaging location above said rails and a retracted bundle-releasing location therebelow.

10. The bundle-forming apparatus of claim 9 in which said transfer rails are transversely displaceable relative to each other between an inner bundle-receiving position for engagement with such bundle supported upon said track to remove the bundle therefrom and an outer position free of any such bundle supported upon said track, and in which said apparatus further comprises motor means for selectively displacing said transfer rails between such inner and outer positions thereof.

11. The bundle-forming apparatus of claim 10 in which said transfer rails are pivotally supported adjacent an end portion thereof for angular displacements between such bundle-receiving and bundle-discharge positions thereof, and in which said apparatus further comprises support structure for such transfer rails including a pivotal support therefor defining an axis about which said transfer rails are angularly displaceable.

12. The bundle-forming apparatus of claim 11 in which said compression section further comprises a trolley mechanism movable along said track and having retaining finger structure selectively displaceable between an extended position in which it projects above said track for engagement by the leading bag in the forwardmost group and a retracted position below said track, and motor means for selectively displacing said retaining finger structure between the extended and retracted positions thereof.

13. The bundle-forming apparatus of claim 12 in which said track is inclined upwardly toward the terminal end thereof, and in which said trolley mechanism iS freely movable along said track and is gravity biased toward the infeed end of said compression section.

14. The bundle-forming apparatus of claim 13 in which the pusher finger structure of said transfer device is selectively movable between an extended group-engaging position and a retracted position remote from any such group, and further comprising motor means connected with said pusher finger structure and operable in timed relation with the displacements of said transfer device to enforce movements of said pusher finger structure with respect thereto.

15. In bundle-forming apparatus, an accumulator section having an infeed end and a discharge end and being operative to advance therebetween successive groups of collated bags or the like delivered to such infeed end, a compression section having an infeed end adjacent the discharge end of said accumulator section and through which such successive groups are transferred for collection and formation into a compressed bundle, and a transfer section operative to displace each such compressed bundle into a banding mechanism or the like, said apparatus comprising bag-supporting means interposed between such infeed and discharge ends of said accumulator section and along which such successive bag groups are advanced, conveyor mechanism located along said supporting means for advancing each such group delivered to the infeed end of said accumulator section toward said discharge end thereof, drive means for said conveyor, longitudinally extending rail structure defining a track along which successive groups transferred through the infeed end of said compression section are collected, a transfer device adjacent the discharge end of said accumulator section and infeed end of such compression section and having pusher finger structure movable into engagement with each successive group arriving at said discharge end, said transfer device being displaceable between a group-engaging position adjacent the discharge end of said accumulator section and a group-releasing position adjacent the infeed end of said compression section for transferring each such engaged group therebetween, drive mechanism for said transfer device to cyclically and repetitively displace the same between such group-engaging and group-releasing positions, longitudinally extending transfer rails extending generally along and adjacent the rail structure of said compression section and being adapted to remove therefrom a bundle collected along said rail structure and to transfer such removed bundle from the the bundle-receiving position of said transfer rails to a bundle-discharge position thereof adjacent such banding mechanism, motor means for selectively moving said transfer rails between such positions thereof, a pair of clamping structures for confining such a bundle therebetween and being respectively disposed adjacent opposite end portions of said transfer section and movable with said transfer rails thereof between such bundle-engaging and bundle-discharge positions, and motor means for selectively displacing said clamping structures between an extended bundle-engaging location above said rails and a retracted bundle-releasing location therebelow.

16. The bundle-forming apparatus of claim 15 in which such successive bag groups are delivered to said accumulator section in spaced-apart relation, and in which said conveyor mechanism is equipped with a plurality of spaced-apart fingers carried thereby for movement into a space provided between successive groups and into engagement with the trailing bag of the group forwardly thereof so as to push the same toward such discharge end.

17. The bundle-forming apparatus of claim 16 and further comprising a delay mechanism located adjacent the infeed end of said accumulator section and being equipped with constraining finger structure cyclically displaceable into the path of movement of such successively delivered bag groups in timed relation with the delivery thereof to momentarily restrict movement of eacH such group and thereby provide a relatively large space between successive groups.

18. The bundle-forming apparatus of claim 17 in which the pusher finger structure of said transfer device is selectively movable between an extended group-engaging position and a retracted position remote from any such group, and said apparatus further comprising motor means connected with said pusher finger structure and operable to extend such pusher finger structure when said transfer device is in the group-engaging position thereof and to retract such pusher finger structure following transfer thereby of a bag group into said compression section.

19. The bundle-forming apparatus of claim 18 in which said transfer rails are transversely displaceable relative to each other between an inner bundle-receiving position for engagement with such bundle supported upon said rail structure to remove the bundle therefrom and an outer position free of any such bundle supported upon said rail structure, and in which said apparatus further comprises motor means for selectively displacing said transfer rails between such inner and outer positions thereof.

20. The bundle-forming apparatus of claim 19 in which said transfer rails are pivotally supported adjacent an end portion for angular displacements between such bundle-receiving and bundle-discharge positions thereof, and in which said apparatus further comprises support structure for such transfer rails including a pivotal support therefor defining an axis about which said transfer rails are angularly displaceable.

21. The bundle-forming apparatus of claim 20 and further comprising a trolley mechanism movable along said track and having retaining-finger structure selectively displaceable between an extended position in which it projects above said track for engagement by the leading bag in the forwardmost group and a retracted position below said track, and motor means for selectively displacing said retaining finger structure between the extended and retracted positions thereof.