US 3902750 A
A device for gripping a piece of cloth or fabric particularly the top piece of cloth of a pile of pieces of cloth or the like flexible material in sheets, characterised in that it comprises a gripper having two flat tapered jaws forming between them an acute dihedral angle, one of which jaws terminates in a pointed tooth situated opposite the gap between two adjacent pointed teeth terminating the other jaw, the said teeth beeing of general triangular configuration and their edges being bevelled towards the interior of the combination formed by the two jaws.
Claims available in
Description (OCR text may contain errors)
United States Patent [191 Roitel [4 1 Sept. 2, 1975 [5 DEVICE FOR GRIPPING PIECES OF CLOTH FABRIC OR THE LIKE  Inventor: Jean Claude Roitel, Paris, France  Assignee: Centre dEtudes Techniques des Industries de lHabillment, Paris, France 221 Filed: Jan. 8, 1974 211 Appl.No.:43l,7v01
 Foreign Application Priority Data Jan. 16, 1973 France 73.01399  US. Cl. 294/88; 271/18.3; 294/104  Int. Cl. B25B 5/06  Field of Search 294/65.5, 88, 103 R, 104,
 References Cited UNITED STATES PATENTS Gottlieb 81/43 Starnborski 294/ 104 4/ l 970 Dawson 3,588,091 6/1971 Stone et al.. 271/19 3,588,092 6/1971 Dubas 271/19 3,712,611 l/l973 Jacquot et a1. 271/11 I Primary ExaminerEvo n C. Blunk Assistant Examiner.leffrey V. Nase Attorney, Agent, or FirmV. Alexander Scher [5 7 I ABSTRACT I A device for gripping a piece of cloth or fabric partic- I ularly the top piece of cloth of a pile of pieces of cloth I or the like flexible material in sheets, characterised in that it comprises agripper having two flat tapered jaws forming between them an acute dihedral angle, one of which jaws terminates in a pointed tooth situated opposite the gap between two adjacent pointed teeth terminating the other jaw, the said teeth beeing 'of general triangular configuration and their edges being bevelled towards the interior of the combination I formed by the two jaws.
4 Claims, 9 Drawing Figures Stewart et a1 271/19 DEVICE FOR GRIPPING PIECES OF CLOTH FABRIC OR THE LIKE The invention concerns devices for gripping pieces of cloth or fabric, particularly the top piece of a pile of pieces of cloth or the like flexible material in sheets, such as plastics material for example. I
Various known devices have already been used, but all of them have disadvantages.
Thus, devices are know which consist essentially of suction nozzles, but their effectiveness is not absolute and the separation of the top piece of cloth is not done without difficulty.
Devices are also known which make use of a member provided with a piece of adhesive tape that is renewed for each gripping operation, or a piece of glass-paper or carding-engine lining, but their operation is still not more reliable.
Another known device comprises a cylindrical tubular member connected to a source of low pressure and having its end provided with teeth, gripping being effected by a sudden pivotal movement of small amplitude of the toothed cylinder, but gripping is again uncertain. 7
Finally, devices are also known which are provided with needles penetrating the .cloth obliquely in either divergent or convergent directions, but such devices are complicated, delicate and very difficult to adjust so that the top piece is always gripped and the piece directly underneath is not gripped also, whereby reliability of the operation is not ensured.
It is the object of the invention to provide a gripping device which does not have the aforesaid disadvantages of the know devices.
For this purpose, the device according to the invention consists of a gripper having two flat tapered jaws forming between them an acute dihedral angle, one of which jaws terminates in a pointed tooth situated opposite the gap between two adjacent pointed teeth terminating the other jaw, the said teeth being of general triangular configuration and their edges being bevelled towards the interior of the combination formed by the two jaws. When such a tool is placed against cloth and the gripper is closed, a thread seized by the points of the teeth of the two jaws respectively, commences to be slightly raised by the effect of the approach of the said teeth, then effectively clamped in an undulated configuration between each of the two bevelled edges of the single tooth and the adjacent bevelled edges of the other two teeth, respectively.
Such a device has a low cost price and a small bulk. It is easy to operate and may be manipulated by hand, but it is advantageously incorporated in a machine having an automatic cycle because it is particularly very sure in operation. It is suitable for dealing with very different cloths or like materials of close or open texture and whose surface condition is even slippery, sized or finished, for example.
The invention will be better understood on perusal of the following description and examination of the accompanying drawings which show by way of nonrestrictive example one embodiment of a gripping device according to the invention. In the drawings:
FIG. 1 is a side view of the device.
FIG. 2 is a corresponding front view.
FIG. 3 is a side view on a larger scale of the two jaws of the tool.
FIGS. 4 and 5 are,,r espectively, corresponding internal front views of the two jaws,
FIG. 6 is aside view of both of the two jaws clamped together, I FIG. 7 shows on a still larger scale a section along the line VII'-VII of FIG. .6 with a thread assumed to be gripped, and
FIGS. 8 and 9 illustrate in side view the gripping'of a thread. I
The device shown in FIGS. 1 and 2 is intended for seizing the top piece of cloth or fabric from a pile 2 of pieces of cloth of any nature, woven or non-woven or even a pile of flexible material in sheets, for example, sheets of plastics material.
The device comprises a gripper 3 having two jaws 4, Srespectively secured to the fixed armature 6 and the movable armature 7 of an electromagnet, denoted in its entirety by 8 and carried, for example, by an arm 9 which may belong, inter alia, to an automatic machine.
The two jaws 4, 5 are tapered and of flat section; they form between them an acute dihedral angle A (FIG. 3), and one of them, for example the jaw 5, terminates in a single pointed tooth 11 (see also FIG. 4), while the other jaw 4 terminates in two adjacent pointed teeth 12, 13 (FIG. 5), between which the single tooth ll of the jaw 5 comes into position when the gripper is closed, as shown in FIGS. 6 and 7.
The teeth 11, 12, 13 are of general triangular configuration and their edges are bevelled towards the interior of combination formed by the two jaws, as shown at l4, 15 for the tooth 11 (FIG. 4) and at 16, 17 for the two teeth 12, 13 (FIG. 5).
Conventional supporting means are used for the pivoting of one jaw relatively to the other jaw. The movable armature 7 of the electromagnet 8 is provided with two apertures 7A which are engaged on two studs 6A of the fixed armature of the electromagnet 8. This arrangement provides for possible pivoting movement of the movable armature 7 with respect to the fixed armature 6. The movable armature 7 is urged for pivoting movement in the direction fl which moves jaw 5 away from jaw 4 by a spring 10, one end of which is attached to a lug 7B of the movable armature 7 while the other end is attached to a further lug 6B of the fixed armature 6. The amplitude of such pivoting movement in the direction of the arrow fl (FIG. 1) is limited by two further lugs 7C which form extensions of the movable armature 7 beyond the pivoting elements formed by the apertures 7A and 6A and which are adapted to engage the adjacent face 6C of the fixed armature 6. The electromagnet 8 is secured to the arm 9 by means of a screw, and the fixed and movable jaws 4 and 5 are respectively secured to the fixed armature 6 and to the movable armature 7 of the electromagnet also by means of screws illustrated in the drawings.
For use, the apparatus is thrust in the open position in the direction of the arrow f (FIG. I) perpendicularly to the surface of the pile 2 of pieces of cloth or fabric, the teeth of the two jaws entering the top piece 1 of the pile of cloth as shown in FIG. 8. The gripper is then closed and there is practically always at least one thread, such as 21, imprisoned between the teeth of the two jaws and which, consequently, is raised slightly between the latter during their closure, and at the same time assumes the undulated configuration shown in FIG. 7 under the effect of the pressure to which it is subjected by the single tooth ll of the jaw 5 engaged between the two teeth 12, 13 of jaw 4. Thus, the thread is not only supported by the ends of the teeth of the two jaws which cross one another, but in addition is clamped between the bevelled face 14 of the single tooth 11 and the bevelled face 17 of the tooth 13 of the other jaw, as well as between the bevel 15 of the single tooth and the bevel 16 of the other tooth 12 of the jaw with two teeth. The thread 21 is therefore very effectively seized by the gripper 3 such that the piece of cloth 1 is lifted off the pile 2, whereupon it can be led to any desired place for undergoing the required treatment.
Furthermore, the apparatus may be used equally well for seizing a piece of cloth already isolated.
Of course, the invention is not limited to the embodiment described and shown; modifications made be made in it according to the applications contemplated without departing from the scope of the invention for that purpose.
1. A device for gripping a piece of cloth made of threads, comprising first and second jaw elements each tapering toward one end, said first element terminating in a triangula'rly pointed tooth, said second element terminating in two spaced triangularly pointed teeth defining therebetween a gap into which said generally triangular pointed tooth of said first element is adapted to fit snugly, and means supporting said jaw elements so that they incline toward one another and toward said tapered ends and so that said tapered ends can be 4 brought together with said tooth on said first element entering said gap between said teeth on said second element, the edges of each of said teeth on each one of said first and second elements being bevelled toward each other, said supporting means comprises an electromagnet having a fixed armature and a movable armature, said fixed armature being connected to said second jaw element, said movable armature being connected to said first jaw element, whereby upon thrusting said device toward a piece of cloth with said tapered jaw elements foremost and separate from each other, activating said electromagnet to bring said tapered jaw elements toward and against each other to cause one thread of said cloth to be held between the teeth of the two jaws and slightly slidingly raised away from said cloth by virtue of said jaw elements being inclined toward one another, said thread finally being clasped in an undulated configuration between said bevelled edges of said pointed tooth 'of said first jaw element and said bevelled edges of said two spaced pointed teeth of said second jaw element.
2. A device as claimed in claim 1 wherein said jaw elements consist of plate members.
3. A device as claimed in claim, 1 wherein said supporting means provide for one of said jaw elements pivoting with respect to the other of said elements.
4. A device according to claim 1 including means resiliently resisting movement of said jaw elements toward one another.