US 3386763 A
Description (OCR text may contain errors)
June 4, 1968 R. w. OTTAWAY ETAL 3,386,763
FLAT PIECE PICKUP HEADS 2 Sheets-Sheet 1 Filed Oct. 21, 1966 [mien f0 rs Robert h/Ottaway Paul G. Rumba]! By theirAttorney June 1968 R. w. o'r'rAwAY ETAL 3,386,763
FLAT PIECE PICKUP HEADS 2 Sheets-Sheet Filed Oct. 21, 1966 United States Patent 3,386,763 FLAT PIECE PICKUP HEADS Robert W. Ottaway, outh Hamilton, and Paul G.
Rumbail, Beverly, Mass, assignors to United Shoe Machinery Corporation, Boston, Mass, a corporation of New Jersey Filed Get. 21, 1966, Ser. No. 588,615 8 Claims. (Cl. 294-611) This invention relates to devices for handling flexible flat sheet material and more particularly to devices for removing such material one piece at a time, from a pile containing many layers of the material.
For handling sheets of relatively impervious material such as paper, cardboard, metal and the like, suction devices are commonly employed. Such devices are generally satisfactory for this purpose but are not satisfactory if the material to be handled is sufliciently porous because of the obvious problem of picking from a pile only one sheet at a time without disturbing the underlying layer or layers of material.
An object of the present invention is to provide an improved pickup head of simplified construction capable of removing one at a time from a pile, a layer of flexible air pervious material such as cloth without disturbing the underlying layer or layers of the material.
To this end and in accordance with a feature of the invention, the pickup head comprises a main body portion carrying fabric impaling means which are movable relatively to the body portion into and out of fabric engaging positions, there being infiatable means which act directly on the impaling means to control the movements thereof into and out of the fabric engaging positions.
The inflatable means, in accordance with a further feature of the invention, comprises a tube or tubes which act directly on structure by which impaling prongs are carried for movement into and out of operative positions so that expansion or contraction of the tube or tubes acts directly to control the positions of the prongs.
The above and other objects of the invention including various novel details of construction and combinations of parts will now be more particularly described with reference to the accompanying drawings and pointed out in the claims.
In the drawings:
FIG. 1 is a perspective view partially broken away of one form of pickup head embodying the invention;
FIG. 2 is a partial section through the front of the pickup head along line IIII of FIG. 1 showing the means for closing the ends of the pneumatic tubes;
FIG. 3 is a sectional view of the head of FIG. 1 with the pickup prongs retracted;
FIG. 4 is a sectional view of the head of FIG. 1 with the pickup prongs extended embodying an alternative prong controlling mechanism;
FIG. 5 is a sectional view of a pickup head similar to that shown in FIG. 1 but with the prongs diverging instead of converging when extended;
FIG. 6 is a perspective view partially in section of yet another form of pickup head;
FIG. 7 is a sectional view of the pickup head of FIG. 6 with the pickup prongs extended; and
FIG. 8 is a sectional view of the pickup head of FIG. 6 with the pickup prongs retracted.
Referring to FIG. 1, it will be seen that the pickup head, which is the subject matter of this invention, is of simple construction and has few parts. Although the pickup head shown consists of several elements fastened together, it will be understood that the major portion of the pickup head could be a unitary molded piece formed of any suitable material such as plastic, cast metal or epoxy filled aluminum. The pickup head as pictured comprises an ir- 3,386,763 Patented June 4, 1968 regularly shaped main body piece 2 having secured thereto a pair of L-shaped side members 4. It is to be noted that the member 2 has a pair of right-angular grooves on each side, which when enclosed by the L-shaped members 4 form rectangular channels to receive the pickup elements 6.
The pickup elements 6 are generally inverted T-shaped members each having a portion 8 slightly extended and terminating in a series of spiked prongs 10 at its outer edge. The uniplanar surface of each of the portions 8 of the T-shaped pickup elements 6 is in slidable engagement with a surface of the pickup head. The mounting allows the elements to move along supporting surfaces of the pickup head to move the prongs between the positions of FIGS. 3 and 4. The stem of the T-shaped pickup element 6 extends upwardly into the rectangular channel formed by the body member 2 and the side members 4 and is flanked by pneumatic tubes 12 and 14, FIGS. 1, 3 and 5, one on either side of the stem or as an alternative, the pneumatic tubes 12 may be replaced by springs 13.
The position of each pickup element 6 is controlled by the associated pneumatic tubes 12 and 14 so that when one of said tubes is inflated the pickup element will slide within the pickup head. The simple alternate expansion of the tubes 12, 14 allows the prongs to extend from and retract into the body of said head. In the alternative assembly, FIG. 4, the tubes 14 will extend the prongs 10 but upon deflation thereof, the prongs will automatically be retracted by means of the springs 13.
It will be seen that by reason of its simplicity, the present device provides not only a pickup device which is reliable without constant attention, but also capable of simple repair in the event of a breakdown.
Further to be seen in FIG. 1 is a sensing bore 16 which is designed to detect the time when the pickup prongs should be extended. In operation, when the pickup head comes into contact with the flat piece to be picked up, a jet of air passing through the bore 16 is impeded, thus providing a back pressure and thus activating a fluidic switch or other similar component (not part of this invention), directing fluid into the tubes 14 and permitting exhaust of air from the tubes 12, forcing the pickup prongs beyond the lower surface of the pickup head. When the head has transferred the piece to the appropriate place, the fluidic switch will be again activated by any appropriate means, forcing fluid into the tubes 12, and exhausting it from the tubes 14 or in the embodiment of FIG. 4 simply exhausting tubes 14, allowing the pickup prongs to retract, and thus discharging the piece (see FIG. 3).
Whereas it is entirely possible and feasible to use separate individual tubes for elements 12 and 14, it is within the contemplation of this invention to use a single tube securely pinched, see FIG. 2, by plates 18 and 20 at the outer end of the pickup head. This method is particularly desirable in that it does not require any actual sealing means. The exposed ends of the tubes 12 and 14 will be attached to an appropriate fluid source and the joining portions securely clamped to prevent leakage.
As can be seen in FIG. 5, the prongs may protrude outwardly as opposed to inwardly as in FIGS. 1, 3 and 4. The operation of this device is identical to that above described and the description will not be repeated.
This form, FIG. 5, of the pickup head is particularly valuable when it is desirable to pick up highly flexible material. The converging prongs might well cause the material to bunch, preventing a positive grip. The diverging prongs will place a tension upon the material, assuring a positive grip during the transfer as well as during the pickup.
FIGS. 6 to 8 show yet another form of a pickup head using the concepts above described. The head uses a unitary molded plastic main body 30 having fingers 32 integrally molded therein. The plastic material may be any one of many which are commercially available, the only requirement being that the material be sufiiciently resilient to withstand repeated flexings. For the purpose of increasing the useful life of the fingers, the work engaging portions are formed of prongs 34 embedded in the fingers 32. The prongs 34 may be of any material which has sufficient resistance to wear.
The operation of the unitary molded specie relies upon the inherent resilience of the finger members 32 to impale the fabric F and partially deflate the tubes 36, 38. When the air blast through sensor 40 is impeded a switch is activated exhausting tubes 36, 38, allowing the prongs 34 to imbed themselves in the fabric F to be transported. When it is desired to release the grasped material, the pneumatic tubes 36, 38 are inflated, expanding fingers 32 and releasing the transported material.
In each of the above disclosed pickup devices the pickup prongs should be of such a length that they will not pass through the top piece of a stack and thus, inadvertently, pick up more than one piece. The amount of penetration is dependent upon both the length of the prongs and the amount of pressure introduced into the pneumatic tubes or, in the case of the head including the integral fingers, the extent of deflation of the tubes or the positions of the fingers when the tubes exert no force. The versatility of the present pickup head enables it to be successfully and efliciently used in a great variety of situations.
It will be understood that the particular machine embodying the invention is shown by way of illustration only and not as a limitation of the invention. The principles and features of this invention may be employed in varied and numerous embodiments without departing from the scope of the invention.
Having thus described our invention, what we claim as new and desire to secure by Letters Patent of the United States is:
1. A pickup head for use in lifting and transporting flexible, flat, air pervious sheet material from a stack of such material comprising a main body portion, material impaling means carried by said body portion for move ment relatively thereto into and out of material engaging positions, and inflatable means acting directly on said impaling means to control the movement thereof into and out of material engaging position.
2. A pickup head as in claim 1 wherein the main body portion and the impaling means are of unitary construction.
3. A pickup head as in claim 1 wherein the main body portion and the impaling means are separate relatively movable units.
4. A pickup head as in claim 1 wherein the head includes as an integral part a sensing device to actuate the impaling means at an appropriate time.
5. A pickup head as in claim 2 wherein the main body portion is of a plastic material and the impaling means are resilient inwardly biased fingers which carry relatively rigid prongs, the inflatable means being used to expand the inwardly and downwardly biased resilient fingers which carry the pickup prongs to release a carried sheet whereas the contraction of said fingers and thus the pickup operation is accomplished by releasing the pressure within said inflatable means.
6. A pickup head as in claim 3 wherein the impaling means converge as they extend.
7. A pickup head as in claim 3 wherein the impaling means diverge as they extend.
8. A pickup head as in claim 4 wherein the sensing device comprises a jet of air passing through the bottom of the pickup head.
References Cited UNITED STATES PATENTS 1,790,688 2/1931 Willer 294-63 2,604,351 7/1952 Rose et a1. 294-61 2,823,947 2/1958 Delzer 294-88 3,176,979 4/1965 Engelrnann 271-18 3,285,649 11/ 1966 Harton 294-61 ANDRES H. NIELSEN, Primary Examiner.