US3405932A

US3405932A - Apparatus for folding and stacking flexible material

Info

Publication number: US3405932A
Application number: US570642A
Authority: US
Inventors: Stanley P Dame
Original assignee: Thompson Manufacturing Co Inc
Current assignee: Thompson Manufacturing Co Inc
Priority date: 1966-08-05
Filing date: 1966-08-05
Publication date: 1968-10-15
Anticipated expiration: 1985-10-15
Also published as: DE1660126A1

Description

Oct. 15, 1968 s. P. DAME 3,405,932

APPARATUS FOR FOLDING AND STACKING FLEXIBLE MATERIAL Filed Aug. 5, 1966 5 Sheets-Sheet 1 INVENTOR. STANLEY P. DAME ATTORNEYS Oct. 15, 1968 S. P. DAME 3,405,932

APPARATUS FOR FOLDING AND STACKING FLEXIBLE MATERIAL Filed Aug. 5, 1966 5 Sheets-Sheet 2 FIG.2

.m uu .u .luuuuuuu uuuuuuuuuu INVENTOR STANLEY P. DAME BY wow, QZZL1J T ATTORNEYS s. P. DAME 3,405,932

APPARATUS FOR FOLDING AND STACKING FLEXIBLE MATERIAL Oct. 15, 1968 5 Sheets-Sheet 3 Filed Aug. 5, 1966 F I G. 3 INVENTOR.

STANLEY P. DAME ATTORNEYS Oct. 15, 1968 S. P. DAME APPARATUS FOR FOLDING AND STACKING FLEXIBLE MATERIAL Filed Aug. 5, 1966 5 Sheets-Sheet 4 FIG. 4

INVENTOR.

STANLEY P. DAME WW, amwa;

ATTORNEYS Oct; 15, 1968 s. P. DAME 3,405,932

APPARATUS FOR FOLDING AND STACKING FLEXIBLE MATERIAL Filed Aug. 5, 1966 5 Sheets-Sheet 5 INVENTOR. STANLEY P. DAME WM, Olazufir 0d;

ATTORNEYS United States Patent 3,405,932 APPARATUS FOR FOLDING AND STACKING FLEXIBLE MATERIAL Stanley P. Dame, Somersworth, N.H., assignor, by mesne assignments, to Thompson Manufacturing Company, Inc., Somersworth, N.H., a corporation of Massachusetts Filed Aug. 5, 1966, Ser. No. 570,642 8 Claims. (Cl. 270-68) ABSTRACT OF THE DISCLOSURE Flexible materials such as leather hides are folded and stacked by means of an endless conveyor which delivers the material onto a horizontally reciprocating table. The table moves in under the conveyor to pickup the first half of the material and then moves in an opposite direction to pick up the remaining half which folds down over the first half. The table carries the folded material into a clamp which grabs the folded end of the article and the table then reciprocates away from the clamp which then releases the folded material onto a stack of previously folded materials.

This invention relates generally to material handling and more particularly is directed towards a novel method and associated apparatus for folding and stacking flexible material such as large sections of leather hides or the like.

In certain material handling applications there is a need to fold and then to stack pieces of flexible material. By way of example, in the leather industry hides undergo a splittin process and then are folded in half before being transferred to a subsequent operation. Since these hides are usually of irregular outline, long, wide and heavy, they are quite difiicult to handle manually. It is therefore a rather arduous manual operation to fold each hide as it comes from the splitting machine and then stack it on a pallet. This is particularly true if the hide is in a slippery condition.

Accordingly, it is an object of the present invention to provide a novel method and associated apparatus for folding and stacking flexible materials.

Another object of this invention is to provide poweroperated apparatus for automatically folding and stacking large flexible sheet form items such as animal hides and the like.

Still a further object of this invention is to provide a folding and stacking apparatus for flexible sheet items which is capable of handling items in a variety of sizes and shapes.

More particularly, this invention features the method of folding and stacking flexible sheet form articles comprising the consecutive steps of advancing the whole article edgewise in one direction through a horizontal plane, dropping the leading edge of the article below the plane, then moving the leading edge of the article in a direction opposite to that of the remainder of the article and in a plane below the plane of the article and at the same speed, then reversing the direction of the leading portion of the article when the leading edge is substantially even with the trailing edge thereof, then moving the both portions of the article in the same direction at substantially the same speed and then finally dropping the now folded article.

This invention also features an apparatus for folding and stacking flexible sheet articles, comprising a first conveyor for advancing the article edgewise in one plane and in one direction at a certain speed, a second conveyor adapted to reciprocate in a plane below the plane of the first conveyor but parallel thereto. The two conveyors are timed so that the leading edge of the article is fed onto the second conveyor so that the leading half is carried under the first conveyor in a direction opposite the movement of the trailing half of the article. When the two edges are substantially even, the second conveyor is reciprocated in the opposite direction and at substantially the same speed as the first conveyor whereby the article is delivered in a folded condition onto the second conveyor. At the end of the stroke of the second conveyor, there is located a gripping mechanism for grabbing the creased end of the article whereby, as the second conveyor is again reciprocated to move out from under the article, it will then be released by the gripping mechanism thus droppin the folded article onto a pile located therebelow.

However, these and other features of the invention, along with further objects and advantages thereof, will become more fully apparent from the following description of a preferred embodiment of the invention with reference being made to the accompanying drawings, in which:

FIG. 1 is a view in perspective of a folding and stacking apparatus made according to the invention,

FIG. 2 is a view in side elevation partly in section of the apparatus,

FIG. 3 is a top plan view thereof,

FIG. 4 is a sectional side elevation of the conveyor drive mechanism, and

FIG. 5 is a detailed sectional view in side elevation of the gripping and dumping mechanism.

Referring now to the drawings, the folding and stacking apparatus is generally organized about an open rectangular frame it mounted in a horizontal plane by means of upright legs 12. The frame and legs form a table-like structure having a forward overhang 14 which supports an endless conveyor belt 16 between a pair of side rails 18 and 29. The leading edge of the overhang 14 carries a lateral nose piece 22 which is positioned at the discharge of a hide splitting apparatus (not shown). It will be understood that when a hide is fed into the splitting machine, it is cut edgewise from end to end with the split or bottom portion being discharged below the overhang 14 to be carried away by a conveyor, for example, while the top portion of the hide, usually known as the side indicated by the reference character 24, is carried onto the conveyor belt 16 in the direction indicated by the arrow 26.

By Way of a general description of the operation of the apparatus, the side 24 is carried rearwardly along the conveyor 16 and is transferred to a horizontally movable carriage 28 mounted rearwardly and below the conveyor 16. The carriage is arranged to be reciprocated from a. position underneath the conveyor 16 to a position over a stack 3G of folded sides 24 piled on a pallet carried by an elevator 32. The carriage 28 is timed so that a left-hand stroke, as viewed in FIGS. 1 and 2, will start the leading edge of the carriage under the conveyor 16 at substantially the same time that the leading edge of the side 24 is being discharged downwardly and to the right from the conveyor 16. The carriage 28 will continue moving to the left as the side is fed onto the carriage until the leading end of the side is substantially even with the trailing end of the side still on the conveyor 16. At this point the carria-ge 28 will retract towards the right at substantially the same speed as the conveyor 16. This retraction of the carria ge will carry the side to the right with the upper and trailing half of the side coming down on top of the lower leading half of the side to thereby fold the side in half.

The folded side is carried to the extreme right by the carriage and against a clamping mechanism indicated generally by the reference character 34. This clamping mechanism will grab the folded end of the side and hold it as the carriage 28 again reciprooates to the left, moving out from under the folded side. When the carriage has moved fully out from under the side, the gripping mechanism will pivot and release the side 'down onto the stack 30. A tamping mechanism 35 associated with the gripping mechanism will push down against the folded edge of the side to keep the top of stack of hides level. The elevator 32 is timed with the driving mechanism to drop in predetermined increments for each cycle so that the top level of the stack is maintained at substantially the same height.

A detailed description of the construction of the various portions of the apparatus will now be given.

Starting with the conveyor belt 16, the entire conveyor assembly, which is carried by the

side rails

18 and 20, is mounted to the frame so as to permit the conveyor assembly to be displaced to the right as viewed in FIGS. 1 and 2. It should be noted that sliding capability is not utilized during operation of the machine but is provided only to facilitate access to the discharge end of the slitting machine which is normally mounted in close relation to the stacker and requires frequent servicing. In any event, the conveyor system comprises the belt 16 and a series of

rollers

36, 38,

4t

44 and 46 over which the belt 16 is roven. The belt follows an inclined portion at its feed end with the upper reach being horizontal. The belt then moves downwardly over roll 40 and then rearwardly under roll 42 where it is carried back and around roll 44, again forwardly to roll 46, and then rearwardly to the leading roll 36. The roll 46 is the driving roll and roll 44 is the tension roll which maintains a constant tension on the belt by means of power cylinders 50 engaging each end thereof. In practice, the power cylinders 50 are actuated edge guiding devices, well known in the art, which respond to the position of the edge of the moving conveyor. With this arrangement the cylinders 50 will respond to maintain an even tension on the belt and also will cause the belt to track through a substantially straight path.

The side 24 is fed over the nose 22 and carried up the inclined portion of the belt, along the fiat upper reach and is then delivered downwardly onto the carriage. In order to guide the side downwardly a funnel or bafiie 52 is mounted over the discharge end of the conveyor 16. Spaced across the discharge end of the conveyor is a series of trips or first timing means 54 in the form of elongated fingers which extend into close relation to the belt. The fingers are actuated by the presence of a side on the conveyor and it will be understood that as the side is guided downwardly through the funnel, the leading edge of the side will strike the trip fingers and the fingers in turn will actuate an associated switching mechanism to simultaneously pivot the finger counterclockwise and out of the way of the side and start the carriage 28 reciprocating to the left as viewed in FIG. 2. In practice, the switches for the detecting fingers 54 are connected in parallel pairs so that at least two switches will have to be closed before the machine is cycled. Otherwise, small bits of leather, for example, may strike one 'of the fingers to start a cycle when no hide is present or when the hide is in an incorrect position.

The several trips are moved out of position by means of a power cylinder 56 drivingly connected to a rocker arm 58 keyed to a horizontal rod 60 supporting the several trips.

When the trips 54 are actuated, they commence a cycling operation of the carriage 2-8. The carriage 28 which at the start of the cycle is in a right hand position as viewed in the FIG. 1, will start moving to the left at substantially the same speed as the conveyor belt 16, the upper reach of which will be moving to the right. The carriage 28 rides on parallel tracks 62 mounted oppositely one another on the inner sides of the frame 10. These tracks extend in under the conveyor belt assembly and engage rollers 64 mounted to the carriage. The carriage is also provided with an elongated rack 66 along either side thereof which rack meshes with a :gear 68 driven by a motor 70 through a chain drive 72. It will be understood that the motor 70 is reversible in order to reciprocate the carriage back and forth as-required. Otherreversible driving arrangements may be provided to actuate the carriage.

In any event, the operation of the carriage is timed to coincide with the side 24 as it is discharged down from the conveyor 16 as it moves past the roller 42. The carriage 28 as it starts moving to the left as in FIG. 4 picks up the leading edge of the side coming otfthe conveyor 16. The carriage starts to move in under the lower reach of the conveyor 16 carrying with it the leading portion of the side. In this fashion the leading or lower portion of the side is carried in a direction'opposite to the trailing upper portion still on the conveyor 16. The carriage continues to move until it reaches the end'of its left hand stroke. At the end of its stroke it will trip a limiting switch causing the motor to reverse the direction of rotation of the gear 68 thereby starting the carriage on a return stroke to the right. The stroke of the carriage is such that it will star-t its return stroke to the right when approximately one half of the side has been deposited on the carriage with the other half still remaining on the conveyor. In this condition the side should come out folded substantially in half. In any event, as the carriage starts moving to the right on its return stroke at substantially the same speed as the conveyor 16 or slightly in excess thereof, the trailing upper half of the side will continue to be fed down onto the carriage only it will now come down on top of the leading lower half of the side already on the carriage and in this manner the side is folded in half.

The now folded side is carried away from the conveyor 16 to the right towards the gripping mechanism 34. The gripping mechanism may be selectively positioned lengthwise of the frame by manipulation of a pair of lead screws mounted on the insides of the frame 10 and engaging followers 82 supporting the gripping mechanism. The lead screws are operated by means of a hand crank 84 located at one corner of the frame and connected to the lead screws by means of an extension rod 86 and bevel gears 88.

The carriage is moved to the right towards the gripping mechanism until it reaches the end of its stroke determined by the position of the gripping mechanism, where it trips another limiting switch or second timing means to again reverse the motor 70 and reciprocate the table 28 to the left back towards the conveyor.

The gripping mechanism 34 includes an elongated scoop 90 mounted to a rotatable support 92. The support 92 is drivingly connected by a rocker arm 94 to a power cylinder 96. Actuation of the cylinder 96 will cause the arm 94 and the scoop 90 to rotate counterclockwise as viewed in FIG. 5 for reasons that will presently appear. Concen trically rotatable about the support 92 is another pair of rocker arms 98 which carry a bar 100. The rocker arms 98 are drivingly connected to power cylinders 102 and by actuation of the cylinders 102 the rocker arms 98 will bias the bar counterclockwise down against the scoop 90. It will be understood that the bar 100 is timed to come down against the scoop when the folded end of the side 24 has been carried up into the scoop as suggested in dotted line in FIG. 5. The bar will come down and grip against the folded end of the side and pinch it against the scoop. Once this has been accomplished, the carriage 28 will start its stroke to the left as viewed in FIG. 5 and move out from under the folded side which is held by the scoop and bar. The side will drape down onto the stack 30 and once the carriage is moved fully out from under the side the cylinder 96 will. be actuated to bias the scoop 90 counterclockwise dropping the folded edge down onto the stack. Once the side is fully released, the cylinder 96 again actuates to bias the scoop back into position to pick up the next side.

Also shown in FIG. 5 is a braking cylinder 104 which serves to bring the carriage 24 to a controlled stop at the end of its stroke.

In order to protect against damage to the scoop or carriage in the event that the side 24 should accidentally get caught between the scoop and the carriage, the leading end of the carriage, indicated at 106, may be in the form of the spring loaded hinge whereby that portion of the carriage will pivot down in the event that a side should jam between the scoop and the carriage.

Once the side is fully released and laid onto the stack the tamping mechanism 35 is automatically actuated so as to press the folded end of the side down fiat against the stack so as to form a smooth even pile of sides. This tamping mechanism comprises a pair of power cylinders 108 which carry a tamping plate 110 positioned over the edge of the stack. Actuation of the cylinders 108 will reciprocate the plates 110 downwardly to push against the top of the stack of sides under pressure and flatten out the top of the stack. In order to insure that the plate moves smoothly under the action of the two cylinders a pair of vertical racks 112 is provided, one rack being associated with each cylinder 108. The lower end of each rack is connected to the plate 110 and moves up and down with the plate. The rack rides in suitable bearings and each rack meshes with a pinion 114. The pinions are keyed to a common cross shaft 116 whereby operation of one rack and cylinder will follow the operation of the other rack and cylinder for smooth operation of the reciprocated plate.

The elevator 32 on which the sides are stacked is essentially a platform provided with threaded followers 118 at each corner thereof engaging vertical lead screws 120. The lead screws 120 are actuated in unison to turn a predetermined amount upon each operating cycle of the apparatus. Each time the lead screws are actuated, the elevator 32 drops for a distance substantially corresponding with the thickness of a folded side deposited thereon. In this fashion the top level of the stack of sides remains substantially constant. When the elevator reaches the bottom most position, the pile of sides is removed and the elevator returned to a starting position. A motor 122 is drivingly connected to the lead screws 120 and is actuated by suitable switches so as to move the elevator in proper timed sequence.

While the invention has been described with particular reference to the illustrated embodiment, it will be understood that numerous modifications thereto will appear to those skilled in the art. Accordingly, the above description and accompanying drawings should be taken as illustrative of the invention and not in a limiting sense.

Having thus described the invention, what I claim and desire to obtain by Letters Patent of the United States is:

1. Apparatus for folding and stacking a flexible sheet article, comprising:

(a) a first conveyor adapted to carry said article in a fiat open condition in one direction through a first horizontal plane,

(b) a second conveyor mounted in a second horizontal plane below said first plane for reciprocation in said one direction and in an opposite direction,

() means for feeding the leading end of said article from said first conveyor to said second conveyor,

((1) first timing means for moving said second conveyor in said opposite direction to receive the leading end of said article and carry it in said opposite direction until the leading end is abreast the trailing end on the first conveyor and then reversing the second conveyor to move in said one direction whereby said trailing end will fold down on said leading end, and

(e) a clamp located adjacent said second conveyor when said second conveyor has reached the extent of its travel in said one direction whereby said article may be held by said clamp as said second conveyor reciprocates in said other direction moving out from under the folded article.

2. Apparatus according to claim 1 including a tamping mechanism having a plate mounted for vertical reciprocation and power means drivingly connected to said plate and timed to move said plate against said article after said article is released by said clamp.

3. Apparatus according to claim 1 including an elevator mounted below said second conveyor in position to receive articles released by said clamp and adapted to support said stack of articles.

4. Apparatus according to claim 3 including elevator control means drivingly connected to said elevator for lowering said elevator in predetermined increments each cycle of operation of said conveyors.

5. Apparatus according to claim 1 including a lead screw and follower operatively connected to said clamp for selectively positioning said clamp with respect to said second conveyor.

6. Apparatus according to claim 1 wherein said first timing means includes an array of article sensing devices arrayed across the discharge end of said first conveyor and adapted to respond to the presence of an article on said first conveyor.

7. Apparatus according to claim 1 wherein said clamp includes a scoop extending across the path of said article in said second plane to pick up the folded end of said article as it is carried in said one direction and a bar coextensive with said scoop mounted for pivotal movement down against said scoop to clamp the folded end of said article and means for pivoting said scoop downwardly to release said article.

8. Apparatus for folding and stacking a flexible sheet article, comprising:

(a) a first conveyor adapted to carry said article in a flat open condition in one direction through a first generally horizontal plane,

(b) a conveyor table mounted in a second generally horizontal plane below said first plane for reciprocation in said one direction and in an opposite direction,

(c) means for feeding the leading end of said article from said first conveyor to said conveyor table,

(d) first timing means for moving said conveyor table in said opposite direction to receive the leading end of said article and carry it in said opposite direction until the leading end is abreast the trailing end on the first conveyor and then reversing the conveyor table to move in said one direction whereby said trailing end will fold down on said leading end, and,

(e) a clamp located in a position adjacent said conveyor table when said conveyor table has reached the extent of its travel in said one direction,

(f) said clamp being adapted to engage said article whereby said article may be held by said clamp when said conveyor table is withdrawn in said other direction.

References Cited UNITED STATES PATENTS 1,270,334 6/1918 Schumacher 27 l84 2,015,550 9/1935 Elberty 270-68 2,549,202 4/1951 Idelman 27188 3,003,760 10/1961 Scheu et a1 27082 EUGENE R. CAPOZIO, Primary Examiner.

P. V. WILLIAMS, Assistant Examiner.