US3601390A

US3601390A - Sheet separating apparatus

Info

Publication number: US3601390A
Application number: US854225A
Authority: US
Inventors: Kenneth O Morton
Original assignee: Cluett Peabody and Co Inc
Current assignee: Cluett Peabody and Co Inc
Priority date: 1969-08-29
Filing date: 1969-08-29
Publication date: 1971-08-24
Anticipated expiration: 1988-08-24
Also published as: DE2042562B2; CA923156A; GB1296816A; FR2059231A5; DE2042562A1; ZA705694B; BE755474A; JPS4913180B1

Abstract

Apparatus for separating layers of limp fabric from a stack, including an angular lifting needle and a second, upright, needle. The lifting needle typically penetrates the top layer and then lifts it onto the second needle. The separated layer, secured on the needles, is transported to a work station where castoff means serve to disengage the fabric from the needles. By adjustment of the lifting needle, more than one layer can be separated from the stack in a single operation. An additional element may be used to physically restrain the stack from moving up with the ply to be separated.

Description

United States Patent Kenneth 0. Morton [72] Inventor 793,009 6/1905 Miller 271/18 T N Y, 1,394,202 10/1921 Leumann 271/26 [21} Appl. No. 854,225 2,003,698 6/1935 Remington 271/25 [22] Filed Aug. 29, 1969 2,374,838 5/l945 Russell et a1 271/29 [45] Patfmted 1971 Primary Examiner-Joseph Wegbreit [73] Ass'gnee Chen Peabody Anorneys- Leo Fornero and Robert J. Dockery Troy, N.Y.

[54] SHEET SEPARATING APPARATUS 11 Claims 14 Drawing Figs. ABSTRACT: Apparatus for separatlng layers of limp fabric from a stack, including an angular lifting needle and a second, [52] [1.5. CI 271/18 upright, needle. The lifti needle typically Penetraes the top l B651 3/22 layer and then lifts it onto the second needle. The separated [50] Field of Search 271/18, 21, layer, Secured on the needles, is transported to a work station 19 where castoff means serve to disengage the fabric from the needles. By adjustment of the lifting needle, more than one [56] References cued layer can be separated from the stack in a single operation. An UNITED STATES PATENTS additional element may be used to physically restrain the stack 142,822 9/1873 Thian 271/18 from moving up with the ply to be separated.

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w z ATTORNEY SHEET SEPARATIING APPARATUS BACKGROUND OF THE INVENTION The field of the present invention is ply separation and more particularly separation of one or more layers of porous material from a stack. The invention is particularly useful in separating a layer of fabric from a stack of many pieces. Particular problems presented by fabric pieces are that they are limp;

porous and are often cut in such a way that the layers are bound together at the edges by the cutting. Vacuum systems have been used to separate sheets of paper from a stack but are generally considered unreliable for separating cloth pieces because of the porosity of cloth. Needles have been used to deliver fabric plies from a stack one at a time. One such arrangement is shown in US. Pat. No. 3,406,961. Another development is illustrated in U.S.- Pat. No. 3,386,763and utilizes angled pins which are urged into the fabric by means of inflatable elements disposed in the pickup head.

These latter mentioned methods are an improvement over vacuum for the most part; however, they tend to pick up or deliver more than one ply due to the tendency of the plies to cling to each other, particularly at their cut edges. the problem is made simpler by initially dissociating the layers after cutting; but in a manufacturing operation this is an expensive proposition, and there is a need for an apparatus which can deliver sheets one at a time directly from the stack as cut. The problem of edge clinging is particularly acute where heated blades are used to cut fabrics having thermoplastic threads since the'threads fuse together making discrete separation of plies difficult.

SUMMARY OF THE INENTION The present invention overcomes various disadvantages found in prior art devices. In the invention, lifting and locking needles are used in conjunction with an element which has been termed a holddown finger. The complete apparatus might utilize several pickup heads or modules operating on the material at different points to achieve an even lifting.

Pressure from a picking or lifting needle is brought to bear against the top sheet of material. This needle is meant to penetrate only the top ply if only that ply is to be picked up. The sheet caught by the lifting needle is then typically penetrated by a set of two locking needles, disposed on either side of the picking needle, as the picking needle is raised in .relation to the locking needles. This action pushes away all but the sheet that is engaged by the picking needle. A cavity is now formed locally at the needles between the top sheet and the rest of the stack. A holddown finger is inserted in the cavi ty to hold the remaining plies as the top ply is pulled away. The

top sheet is then moved to a work station or a separate delivery means such as a belt feed. The material is disengaged from the pickup heads by drawing back the picking needle and pushing the sheet off the locking needles.

A primary feature of the invention is that it will separate a selected number of sheets effectively and efficiently with the required reliability. The invention may be used to separate sheets ofvarying porosity.

Another feature is that the separated sheets may be delivered to a working station at a point away from the stack.

THE DRAWINGS The invention will be more easily understood with reference to the drawings whereini FIG. 1 is a view of a pickup module partially in section;

FIG. 2 is a plan view of a lever arm holding picking needles;

FIG. 3 is an elevation ofthe lever ofFIG. 2;

FIG. 4 is a plan view of the module of FIG. 1;

FIG. 5 is a side elevational view of the module of FIG. 1; FIG. 6 is a detail showing a sheet being separated from a stack;

FIGS. 7a and 7b are views of a typical picking needle;

FIGS. 80 and 8b are views of a typical. locking needle;

FIGS. 9a and 9b are views of a holddown mechanism;

FIG. 10 is a side elevational view of an apparatus employing several of the modules of FIG. 1; and 1 FIG. 11 is a plan view of the apparatus of FIG. 10.

The drawings should be understood to be more or less of a schematic representation. Like numerals identify like elements in the several views.

DESCRIPTION OF PREFERRED EMBODIMENTS FIG. 1 shows a picking module designated as M which includes lever arm 10 pivotally mounted on crank 11 at pin 12. The crank is secured to a plate 14 by pin 15 so that the crank is free to rotate about the pin. A spring 17 is carried in housing 18 at an end and engages a notch 19 in the crank arm. The spring is shown under partial compression so that crank 11 will tend to rotate clockwise about pin 15 unless restrained in some fashion. Since arm 10 floats on the crank at the end opposite the spring, the entire lever arm 10 will move generally to the left (as seen in the drawing) as the crank rotates clockwise and will move generally to the right as the crank rotates counterclockwise. The motion of arm 10 is controlled additionally by spring 20 which exerts a downward force on the working end of the arm, by stop 21 and by actuator 22. The whole assembly is mounted between plate 14 and a second plate which is not shown in the drawing.

When the bearing surface 23 of the assembly, which is formed by the bottom-most edge of the plates and the housing,

. is held stationary the actuator is free to move up and down in .10 as the actuator moves up and down. The actuator arm restrains the crank from rotation when in its up position and in its downward travel operates to swing the working end of the lever arm 10 up by reason-0f the rotation of the lever about its 7 pivot 12.

Referring now to FIG. 2, two picking needles designated as 30 are shown located in the working end of the lever arm 10. Alternately a single picking needle or a plurality of needles could be used. The needles are clamped in place by clamp portion 31 which is held by bolt 32.

FIG. 3 shows the shape of the clamp portion of the lever. Preferably an open throat 33 is formed between the needle and the clamp portion. This throat may typically be formed by cutting back the part of the clamp near the head of the picking needles. The throat allows the fabric being lifted to ride up on the needle without restraint, thereby reducing the tendency of the needle to tear the threads of the fabric. A cavity 34 may be included in order to prevent lint from collecting in the throat and to further prevent any restraint on the fabric other than that provided by the penetration of the needles. It has been found advantageous to have the throat clearance about onehalf the thickness of the plies being separated. The lever should be so shaped that there are bearing

surfaces

35a and 35b in front and in back of the needles. These surfaces serve to flatten out any puffing of the plies of fabric in the area of the needles which might be caused by the action of surface 23 (FIG. 1) as the latter surface is urged down against the stack of fabric sheets. In the discussion, reference will generally be to a situation where only a single ply is separated from a stack as this is the usual case, however, several plies can be picked simultaneously if it is desirable to do so in a particular instance. The number of plies separated will depend upon the amount the picking needles extend beyond the bearing surfaces 35a and 3511.

FIG. 4 illustrates the disposition of a second set of needles 36 utilized in the picking module. These needles cooperate with the picking needles and are termed locking needles because they assist in holding the separated ply during carriage of the ply from the stack to a new position. The locking needles are spaced far enough apart that the lever 10 with its picking needles can move up and down between the locking needles and are secured to the module by clamp 53 which defines a U-shaped slot 52 (FIG. 1). The locking needles serve additionally to discourage picking of more than the desired number of plies.

FIG. 5 shows the picking module with both face plates in place and with the lifting lever arm in a down position. Actuator 22 is up and the hidden (or back) end of the lever 10 is resting against the stop 21 (FIG. 1). This is the normal position of the lever prior to picking.

The figure shows a trip mechanism which includes two trip levers 40a and 40b carried on a bushing located on the hous- 7 ing. Lever 40a acts against a pin 41 pressed into a hole in the crank. Upward movement of 40a causes a counterclockwise rotation of the crank, which in turn pulls the lifting needles to the right. This action is utilized to disengage the picking needles from the fabric and willbe discussed later in relation to operation of the module. Lever 40b includes a cam 42 which acts against latch 25 to cause the latch to disengage the actuator 22, allowing spring (FIG. 1) to push the picking needles downward as actuator 27 is forced upward by the action of the actuator spring. The downward movement of the bearing surfaces 35 provides a means of casting off the ply from the locking needle after the lifting needles have been disengaged from the fabric.

The operation of the module may be better understood with reference to a description of the interaction of the various elements during a pickup and castoff sequence. Referring now to the drawings discussed hereinbefore and particularly to FIGS. 1 and 5, the module is brought down against the top ply F ofa stack of fabric sheets with the picking needle being the first part of the module to touch the top sheet or ply of fabric. This may be accomplished by letting the lever arm carrying the needle extend slightly below bearing surface 23 as depicted in HQ 5. Since the picking needle is on the end of a pivot arm with a pivot point above the needle when the needle first engages the fabric, there is, in addition to upward movement, a slight forward (to the left in the drawing movement which assists in providing a good pick. The bearing surface of the module then Comes to rest against the stack and serves to hold the stack in place against the force exerted by the picking needle which now starts a movement to the left as the movement of the actuator 22 allows crank 11 to rotate clockwise. The picking needle, having engaged the layers to be separated, will move upward as the actuator on which the module is carried is pushed down against the lever 10. The top ply is now securely on the picking needle and is pulled up and onto the locking needles.

The preferred movement of the picking needle is first generally down and against the stack and then with a component of movement generally parallel to the stack and finally upward. The main problem is to have the angled picking needle penetrate to the desired depth depending on how many layers of fabric are to be separated from the stack. The picking needles might, for example, be initially pushed into the cloth in a direction along the axis of the needle shaft until the desired penetration is achieved and then moved up and away from the stack.

There may be a slight movement of the picking needle away from the locking needle as the picking needle lifts in order to create tension on the cloth between the needles which will more securely lock the sheet on the needles Another way of encouraging a slight tension is to angle the locking needles such that, as the cloth rides up the needle, it is carried away from the lifting needle.

Preferably the locking needles do not extend down to the level of the bearing surface 23. It is desirable that on the downward movement of the module the locking needles do not engage any of the other plies as this would interfere with the action of the picking needle and might cause undesirable localized stretching in holding the fabric against the forward motion of the picking needle when the picking needle first engages the top ply. Additionally, the locking needles are held above surface 23 to prevent them from being forced through sheets of fabric which are not to be separated on the particular cycle. Should the locking needles initially engage sheets other than those to be separated, their ability to push away unwanted layers would be impaired.

Referring now to FIG. 6, when the picking needle is fully raised the fabric is disposed as shown in FIG. 6, being held securely in place on the needles. The latch 25 (FIG. 1) locks the actuator arm down which in turn secures the picking needle in the up position.

The needles used may have a variety of shapes, however, certain shapes are preferable. FIGS. 7a and 7b show the preferred shape for the picking needle (or needles). The needle is ground to a fine point and has a flat triangular shape on either side. The needle should have a flat top side in order to form an even throat dimension when installed in the clamp of the picking lever. The bottom of the needle exhibits a very then portion 70 which creates a shoulder 71. This shape allows a minimum resistance to penetration of the needle up to the shoulder which then provides abruptly a greatly increased resistance to further penetration. Thus, the shape of the picking needle may be utilized to assist in obtaining the desired picking characteristics. The amount of diagonal penetration is controlled by the restrictive shape of the picking needles and/or by the extension of the needle beyond surface 35b.

Referring now to FIGS. 8a and 8b, the locking needle (or needles) has a flat top like the picking needle but has a gradually sloping bottom surface 72. When the picking needle engages the top ply and begins to raise it, the ply is stretched somewhat so that there is some looseness created about the point where the locking needles first engage the fabric. Therefore, the top ply will more easily move up the locking needles then will lower plies and so the locking needles serve the additional function of discouraging picking of more plies than are engaged by the picking needle.

Although the module previously described may be utilized alone, for many situation an additional element may be used in conjunction with the picking module to assure that only the desired number of plies will be separated from the stack.

When fabric plies are to be separated from a stack which has been die cut, there is a pronounced tendency of the plies to stick together at the edges. In such a situation, the picking module can successfully separate the plies at a point away from the edge but the edges may remain stuck, making it difficult to transport only the top ply away from the stack, especially without disturbing the stack.

A second element termed a holddown finger may be utilized to aid in obtaining positive ply separation even when the edges stick together. Referring now to FIGS. 9a, 9b, 10 and 11, the holddown finger 50 is connected to a suitable actuating mechanism designated generally as 51. Preferably the finger is mounted with some play up and down through spring pressure so that it can engage the slot 52 formed by the clamp 53 which secures the locking needles. (FIG. 1).

One method of mounting the holddown finger is illustrated in FIGS. 9a and 9b. The finger 50 rides in slot on roller 81 and cam 82. A link 83 is attached to piston 85. As the piston 85 extends, the link attached to cam 82, urges the finger up and back. The upward movement is stopped when the cam 82 bears on the top edge of the slot 80. When the piston 85 retracts, the finger moves out and down, passing through the U-shaped slot 52 formed in the clamp 53. (See FIG. I).

In instances where the finger may have to go through a seam formed at the cloth edges by fusing or entanglement of the fibers during cutting, the locking needles will act to keep down all but the picked sheets. The finger may actually turn back the plies before it breaks the edge seam, but this will cause no problem since the finger will simply be urged into the cavity formed between the picked ply or plies and the rest of the stack.

Referring back to FIG. 1, a slotted cap 105 is screwed to the top of the actuator 22. The leg of an L-shaped arm extends into the slot of the cap at one end and is swingably attached at its other end to mounting bracket 86. A spring :91 provides I sufficient tension to keep key 90s in engagement with slot 22s.

respective actuators 22 by virtue of the position of rods 92 in relation to the top of the actuator. As the pistons of cylinders 102 extend, the rods 92 push the actuators down. The rods are so located that at the picking station, the actuators are unlocked and are free-to move up and down, the rods having pushed arms 90 (FIG. 1) to the left as the modules move to the right and into position for pickup. The modules move down until they come to rest against the stack F after which the ac tuators continue downward, causing the lever arms 10 (FIG.

1') to lift. Once the separation is accomplished and the top ply is securely on the needles, the cylinders 102 retract and pull the modules up. When the modules are fully raised the indexing belt 103 moves, carrying the modules laterally toward the discharge station. The spring-actuated locking arm 90 (FIG. 1) secures each module in the up position of transport to the discharge station. I

Castoff at the discharge station is accomplished when trips 104 actuate arms 40b (FIG. .5) causing the trip levers 40a to contact and rotate crank pins 41 clockwise thereby disengaging the picking needles and causing the picking levers 10 to snap down so that the fabric is pushed off the locking needles. The lower arms 40b are similarly actuated by trip 104 when the modules are mounted in a position 180 from that shown in FIG. 5.

FIG. 11 is a plan view of the pickup and

discharge stations

100 and 101 The figure shows one possible arrangement of modules to lift a large piece. Four modules are used, one near each corner. The figure also shows the location of the holddown fingers 50 in relation to the modules.

Means may be provided as shown in FIG. 10, to maintain the stack at a particular level as layers are removed. Rack 106 and pinion 107, connected to motor 108 operate platform 109 such that the level of the top layer of the stack remains constant as pieces are picked from the stack.

' It will be appreciated from the foregoing that-there are a variety of ways of achieving the interaction of the various parts described and it will be appreciated that a wide variety of changes may be made without departing from the scope of the invention. For example, certain features of the apparatus may be used independently of others and equivalents may be sub- .stituted for the various elements and steps all within the spirit and scope of the invention.

Iclaim:

1. Work handling apparatus for separating a predetermined number of sheets from a stack of many sheets, comprising in combination: a picking needle for engaging and lifting said predetermined number of sheets away from the stack; and a locking needle projecting generally vertically toward the top surface of the stack and located in the vicinity of the picking needle such that the predetermined number of sheets lifted away from the stack by the picking needle is carried up the locking needle by the upward movementof the picking needle.

2. The method of separating a predetermined number of sheets from a stack of many sheets including the steps of lifting only the predetermined number of sheets from the stack on an 3. Work handling apparatus for separating a predetermined number of sheets from a stack of many sheets, comprising in combination: a picking element having at least one picking needle projecting therefrom; means for moving the element with respect to the stack first generally downwardly and then with a component of movement substantially parallel to the stack such that the needle engages at least the predetermined number of sheets, and then away from the top surface of the stack, to lift said predetermined number of sheets away from the other sheets in the stack; at least one locking needle projecting generally downwardly toward the top surface of the stack and located in the vicinity of the picking needle such that the predetermined number of sheets lifted away from the stack by the picking needle is carried up the locking needle by the upward movement of the picking element; whereby the predetermined number of sheets is secured on said needles by reason of the tension created between the picking needle and the locking needle.

4. Work handling apparatus for separating a predetermined number of sheets from a stack of many sheets, comprising in combination: a picking element having a needle projecting therefrom at an angle of less than with respect to the top surface of the stack; means for moving the element with respect to the stack first generally downwardly and then with a component of movement substantially parallel to the stack such that the needle engages at least the predetermined number of sheets, and then away from the top surface of the stack, to lift said predetermined number of sheets away from the other sheets in the stack; at least one locking needle projecting generally downwardly toward thetop surface of the stack and located in the vicinity of the picking needle such that the predetermined number of sheets lifted away from the stack by the picking needle is carried up the locking needle by the upward movement of the picking element; whereby the predetermined number of sheets is secured on said needles by reason of the tension created between the picking needle and the locking needle.

5. Work handling apparatus for separating a predetermined number of sheets from a stack of many sheets, comprising in combination: a picking element having at least one picking needle projecting therefrom; means for moving the element, with the needle disposed at an angle of less than 90 with respect to the top of the stack, first generally downwardly and then with a component of movement substantially parallel to the stack such that the needle engages at least the predetermined number of sheets, and then away from the top surface of the stack, to lift said predetermined number of sheets away from the other sheets in the stack; at least one locking needle projecting generally downwardly toward the top surface of the stack and located in the vicinity of the picking needle such that the predetermined number of sheets lifted away from the stack by the picking needle is carried up the locking needle by the upward movement of the picking element; whereby the predetermined number of sheets is secured on said needles by reason of the tension created between the picking needle and the locking needle.

6. The'apparatus of claim 3 including means for securing the sheets of said stack from sliding movement at least during the time when the movement of said needle has a component substantially parallel to the top surface of the stack.

7. The apparatus of claim 3 including means, in addition to any of said needles, from restraining the sheets of the stack other than said predetermined number of sheets from upward movement away from the stack, and means for inserting said restraining means between said other sheets and said predetermined number ofsheets during the separating.

8. The apparatus of claim 1 including means for moving the needles, without changing their position relative to each other, laterally to a point remote from the stack, means for disengaging the picking needle from the separated sheets, and means for pushing the separated sheets off the locking needle.

9. The method of separating a predetermined number of sheets from a stack of many sheets including the steps of lifting only the predetermined number of sheets from the stack on an angled needle and, during the lifting, drawing the said predetermined number of sheets up a second needle disposed generally vertically, transporting the said number of sheets to a location remote from the stack, disengaging the angled needle from said sheets and then pushing the sheets offsaid second needle.

10. Work handling apparatus for separating a predetermined number of fabric sheets from a stack of many sheets comprising in combination: a picking needle for engaging and lifting said predetermined number of sheets away from the stack; and a locking needle adapted to project generally vertically downward and in the vicinity of the picking needle such that the locking needle engages the said sheets only as the predetermined number of sheets is lifted away from the stack by the picking needle, and such that the predetermined number of sheets lifted away from the stack by the picking needle is carried up the locking needle by the upward movement ofthe picking needle.

11. Work handling apparatus for separating a predetermined number of sheets from a stack of many sheets, comprising in combination a picking element having at least one needle, means for moving the picking element first generally downward and then with a component of movement which is substantially'horizontal such that the needle is adapted to engage said predetermined number of sheets, and then upward, to lift said predetermined number of sheets away from the rest of the stack; at least one locking needle projecting generally downward and located near the picking needle such that said predetermined number of sheets is carried upward against the point of the locking needle.

Claims

1. Work handling apparatus for separating a predetermined number of sheets from a stack of many sheets, comprising in combination: a picking needle for engaging and lifting said predetermined number of sheets away from the stack; and a locking needle projecting generally vertically toward the top surface of the stack and located in the vicinity of the picking needle such that the predetermined number of sheets lifted away from the stack by the picking needle is carried up the locking needle by the upward movement of the picking needle.

2. The method of separating a predetermined number of sheets from a stack of many sheets including the steps of lifting only the predetermined number of sheets from the stack on an angled needle at a point near an edge of said stack and, during the lifting, drawing said predetermined number of sheets up a second needle disposed generally vertically to form a cavity near the edge, inserting a restraining element into the cavity to hold down the remaining sheets in the stack, and then completing the separation of the predetermined number of sheets from the stack by moving both of said needles away from the stack.

3. Work handling apparatus for separating a predetermined number of sheets from a stack of many sheets, comprising in combination: a picking element having at least one picking needle projecting therefrom; means for moving the element with respect to the stack first generally downwardly and then with a component of movement substantially parallel to the stack such that the needle engages at least the predetermined number of sheets, and then away from the top surface of the stack, to lift said predetermined number of sheets away from the other sheets in the stack; at least one locking needle projecting generally downwardly toward the top surface of the stack and located in the vicinity of the picking needle such that the predetermined number of sheets lifted away from the stack by the picking needle is carried up the locking needle by the upward movement of the picking element; whereby the predetermined number of sheets is secured on said needles by reason of the tension created between the picking needle and the locking needle.

4. Work handling apparatus for separating a predetermined number of sheets from a stack of many sheets, comprising in combination: a picking element having a needle projecting therefrom at an angle of less than 90* with respect to the top surface of the stack; means for moving the element with respect to the stack first generally downwardly and then with a component of movement substantially parallel to the stack such that the needle engages at least the predetermined number of sheets, and then away from the top surface of the stack, to lift said predetermined number of sheets away from the other sheets in the stack; at least one locking needle projecting generally downwardly toward the top surface of the stack and located in the vicinity of the picking needle such that the predetermined number of sheets lifted away from the stack by the picking needle is carriEd up the locking needle by the upward movement of the picking element; whereby the predetermined number of sheets is secured on said needles by reason of the tension created between the picking needle and the locking needle.

5. Work handling apparatus for separating a predetermined number of sheets from a stack of many sheets, comprising in combination: a picking element having at least one picking needle projecting therefrom; means for moving the element, with the needle disposed at an angle of less than 90* with respect to the top of the stack, first generally downwardly and then with a component of movement substantially parallel to the stack such that the needle engages at least the predetermined number of sheets, and then away from the top surface of the stack, to lift said predetermined number of sheets away from the other sheets in the stack; at least one locking needle projecting generally downwardly toward the top surface of the stack and located in the vicinity of the picking needle such that the predetermined number of sheets lifted away from the stack by the picking needle is carried up the locking needle by the upward movement of the picking element; whereby the predetermined number of sheets is secured on said needles by reason of the tension created between the picking needle and the locking needle.

6. The apparatus of claim 3 including means for securing the sheets of said stack from sliding movement at least during the time when the movement of said needle has a component substantially parallel to the top surface of the stack.

7. The apparatus of claim 3 including means, in addition to any of said needles, from restraining the sheets of the stack other than said predetermined number of sheets from upward movement away from the stack, and means for inserting said restraining means between said other sheets and said predetermined number of sheets during the separating.

9. The method of separating a predetermined number of sheets from a stack of many sheets including the steps of lifting only the predetermined number of sheets from the stack on an angled needle and, during the lifting, drawing the said predetermined number of sheets up a second needle disposed generally vertically, transporting the said number of sheets to a location remote from the stack, disengaging the angled needle from said sheets and then pushing the sheets off said second needle.

10. Work handling apparatus for separating a predetermined number of fabric sheets from a stack of many sheets comprising in combination: a picking needle for engaging and lifting said predetermined number of sheets away from the stack; and a locking needle adapted to project generally vertically downward and in the vicinity of the picking needle such that the locking needle engages the said sheets only as the predetermined number of sheets is lifted away from the stack by the picking needle, and such that the predetermined number of sheets lifted away from the stack by the picking needle is carried up the locking needle by the upward movement of the picking needle.

11. Work handling apparatus for separating a predetermined number of sheets from a stack of many sheets, comprising in combination a picking element having at least one needle, means for moving the picking element first generally downward and then with a component of movement which is substantially horizontal such that the needle is adapted to engage said predetermined number of sheets, and then upward, to lift said predetermined number of sheets away from the rest of the stack; at least one locking needle projecting generally downward and located near the picking needle such that said predetermined number of sheeTs is carried upward against the point of the locking needle.