US2530312A

US2530312A - Wire stitching mechanism

Info

Publication number: US2530312A
Application number: US105621A
Authority: US
Inventors: Nasmith John Irving
Original assignee: Vickers Armstrongs Ltd
Current assignee: Vinters Armstrongs Ltd
Priority date: 1948-07-29
Filing date: 1949-07-19
Publication date: 1950-11-14
Anticipated expiration: 1967-11-14
Also published as: DE929663C; FR991051A; CH279382A

Description

J. l. NASMITH WIRE STITCHING MECHANISM Nov. 14, 1950 3 Sheets-Sheet 1 Filed July 19 1949 M W: a W, a, w k I u N. f

Filed July 19, 1949 3 Sheets-Sheet 2 S r n z 6 4 275w [xv/Ms MIM/TH NOV. 14, 1950 J, N M T 2,530,312

WIRE STITCHING MECHANISM Filed July 19, 1949 V s Sheets-Sheet a zl llErlrolt: r700! [Av N0 llnpmlra Patented Nov. 1 4, 1950 WIRE STITCHING MECHANISM" John Irving Nasmith, London, England-,assignorto Vickers-Armstrongs Limited, London, England, aBritish company Application July19, 1949; Serial No. 105,621

In Great Britain July 29', 1948 7 Claims. (Cl. 12)

In the functioning of discontinuous -wire stitching mechanism, it is always necessary to feed and cut: olf from the supply spool a length of wire, hereinafter also called a staple blank, from which the staple issubsequently formed.

In the general case, the position of the. cutting mechanism and the amount of wire fed to form the staples, must be varied to suit thethicknessof work being operated upon. In known wire stitching mechanism, when short staples are used for small thicknesses, the cut-off mechanism has to be brought close in towards'the central axis along which the staple is formedand driven, and this introduces constructive disadvantages in that the Various members operative in forming and driving the staple cannot be made as robust and durable as desirable, these deficiencies being particularly felt when thick or otherwise difficultly penetrable materials have also. to be operated upon.

It is one object of the present invention to provide means whereby these constructive deficiencies are avoided.

According to the invention, wire stitching mechanism comprises means whereby the fed and cut staple blank required to form the staple is bodily transported from a position in which it is severed from the stock to another functionally unrelated position in which it is subsequently formed and driven. 7

Such transporting of the cut length of wire may vary in nature according to the. type of wire stitching mechanism adopted or according to the means available for driving the transporting member or mechanism, subject ,to the condition necessary to carry the invention into practical effect, namely that the longitudinalaxis of the blank is moved between planes not parallel to one another.

In. one of the possible modes of applying the invention the staple blank is transported by rotatic-nal-motion about asuitably chosen. axis-dirooted at right-angles to the length of the staple blank. Such axismay beisituated' at a, position removed from the axis in which the forming takes placeby a distance sufficient to allow theobenefits of the invention to be realised, aconvenientl con,- struction being one in which the said rotation axis is parallel to the forming axis and cuts the long axis of the blank.

A new transporting element. and its operating mechanism are introduced for this transporting purpose into the stitching mechanism. Alternatively one of the elements taking part in the forming of the staple may be modified tofulfill also the function of the transporting element.

In this example the verticalplanethrough the line of feed, in which wire'stockisfediand cut ofI, is situated at rightangles to the verticalplane in which the staple is formedfand to'one sideof the axis of the formed staples these positions being constructively, but not functionally, related, the wire transporting element thus carrying the cut blank between position at right angles to each other and being. mounted for. this purpose on a suitably disposed vertical axis in the ma chine framing.

In the example referred tothe transporting element, operating as described, is also adapted to co-operate in forming the staple in conjunction with the member known. and referred toiherein after as the upper staple former, and also known as the outside former. i

The transporting element thus performs also the oiiice of the member referred to hereinafter as the lower forming element and commonly known as the bending block, loop. bar or inside former of known wire stitching mechanism In practice, cases may occur in which the introduction of a transporting element separatev from' the head of a wire stitching machine incorporating mechanism; according to the present invention,

Figure 2 is a side elevation of a cam and an actuating member therefor appearing in Figurel. Figure 3 is a side elevation of the, stitching headand associated parts of the machine frame, and taken partly in section along, theline III-III of Figure 1. i, a

Figure 4 is a fragmentary plan viewtaken partly in section along the line IV-IV of Figure 3 and indicating the two end positions of the transporting element. I c

Figure 5 is a front elevation showing the parts at a time in the'working cycle difierent from. that inFigure 1. L V i In these figures the fixed parts of the machine frame, indicated by the reference I, are shown only insofar as necessary to make clear the construction and operation of the mechanism acf cording to the invention. i W indicates the wire stock, which is fed'i'nter mittently by feed gripper 2 and non-return gripper 3, through wire guiding

devices

4, 5. and

i these defining a horizontal line of feed indi- A typical example of a construction, carrying cated in the drawing by X--X. The lengths of wire from which the staples are formed are sevcred from the stock by a knifel'. The mechanism for actuating the feed grippers, the non-return grippers, and the knife 'I form no part-of the 3 scribed. Similarly it is to be understood that means are provided for adjusting the length of wire to be fed.

The arrangement of the staple forming and driving elements, and the transporting element, and the actuating mechanism therefor is as follows.

A horizontal cam shaft 8 rotating in fixed bearings in the stitching head carries

cams

9 and 10, for controlling, in the manner hereinafter described, the motion of an outside staple former I l and also actuating by means to be further described a staple driver l2, the said former and driver being guided for vertical movement in the stitching head along a common axis and defining a vertical plane, indicated by Y-Y, in which the staple is formed. The rear side of the staple former is recessed to take a cross-head I3, carried at the top of the staple driver and having a substantially horizontal track [4 for a cam roller mounted on a pin [5 secured to the earn 9. The centre of the cam track is dipped at the parts 3|, 32 for a purpose to be described.

A pin ll, fast to the former H passes through a vertical slot I8 in the driver l2, and carries a cam roller l9 co-operating with the periphery of cam It for controlling the down stroke of the former I l.

A cam roller 20, mounted on a pin 2| at the top of. the former ll, co-operates with the periph'ery of cam 9 for controlling the return stroke of the former ll.

A barrel cam 22, has a peripheral groove 23 covering an angle of 90, and is rotatable, in fixed bearings in the frame, about a vertical axis cutting the line of feed of the wire.

The transporting element 24, which also fulfils the function of an inside former, is keyed fast to the bearing spindle 25 of the barrel cam. The head 26 of the transporting element has a Wire receiving groove 21', and is otherwise shaped as aninside former, being of the necessar width to allow the forks of the outside former H to pass on either side when forming the staple,

" A'cam roller 28 runs in the cam groove 23, and is carried at the end of a cam actuating member in the form of a connecting rod 28, vertically guided in the frame and grooved at 33] to receive the end of the cross-head l3 carried by the staple f The cam groove 23 is cut so that when the connecting rod 29 is vertically reciprocated b the staple driver 52, the barrel cam, and the transporting element 24, swings between two end positions at right-angles, in one of which, shown in s;

full lines in Figures 1, 3 and 4 the groove 2'! of thetransporting element is in the forming plane YY, and in the other position, shown in broken lines inFigure i, the groove 2? is in line with the line of feed X--X. In each of these positions the transporting element is stationary for a pcriod representedby the straight portions of the cam groove 23. The cycle of operations is. as follows:

Assuming the parts are in the forming position,shown in full lines in Figure 4, a staple blank A, has been fed to the element 24, cut off, and transported into position beneath the outside staple former and staple driver. The blank A is now about to be formed and driven. On cam shaft 8 and the cam assembly 9, [B rotating clock-wise, cam roller l5 begins to move to the right in the cam track [4. Whilst the cams are rotating through somewhat less than 90, correequivalent position on the right-hand side of the forming axis, cam roller28 moves a small distance up and down in the upper straight portion of cam groove 23, the transporting element remaining stationary. During this time the periphery of cam ID has moved cam roller l9, and with it the upper former II, a suflicient distance downward to form the staple, the head of which is still held in the groove 21.

On continued rotation of cam shaft 8, the cam roller l5 and driver [2 move down on the driving stroke, and when the cams have moved 180 from the position of Figure 1, the cam roller 28 has travelled into the lower straight portion of cam groove 23, therebyturning the barrel cam and the element 2d counterclockwise through 90 to the feeding position shown in chain lines in Figure 4. During and after this time the formed staple is being driven into the fork, the outside staple former ll meantime remaining in its lowest position due to the shape of the periphery of the cams.

In the feeding position a fresh length of wire is fed by the feed grippers 2 and 3 to the transporting element 2% and is out on.

The driver l2 in the meantime is completing its down stroke. In this portion of the cycle the crank pin 56 and roller 15 are moving from right to left in the cam track l4, and, when passing the central curved portions 3!, 32 of the cam track, whose curvatures correspond to the circular are described by the roller is on the cam shaft centre, the driver l2 remains stationary and the roller 28 remains stationary in the lower straight portion of cam groove 23. During this part of the stationary dwell period the driven staple is clinched, Figure 5 shows the position of the parts when the cam roller (5 is approaching the end of the curved portion 3| of the track.

When the cam roller it has reached the left hand end of the circular portion of the cam track id, the driver 52 rises and completes its return stroke to the position of Figure 1, the former I! meanwhile also assuming its uppermost position, and the element 24 after a further stationary period moving again into the forming position to present the fresh blank in position beneath the upper forming and driving elements. The cycle of forming, driving, and feeding as above described is now repeated.

With the construction according to the invention, the cutting off mechanism need never be brought close to the central forming axis of the formed staple and the cutting off and forming and driving elements can be made as robust as desirable without restriction.

The invention may be carried into effect and adapted to the various types of Wire stitching mechanism in different constructive ways subject to the introduction of a transporting element or the constructive modification of an existing element to operate between the two independent positions and so transport the cut blanks as and when required.

I claim:

1. In wire stitching mechanism of the kind in which an outside staple former and a staple driver reciprocate along a common axis to form and drive staples, means for intermittently feeding wire stock along a line removed from said common axis and substantially at right angles thereto, a transporting element adapted to receive and hold the fed wire in the line of feed, means for cutting off a staple blank from the fed p nd ng to the travel of cam roller [5 to an wire, and means for moving the transporting element from the feeding position in which the wire is fed and cut into the forming position in which the blank is formed into a staple and driven into thework, the said feeding and forming positions being such that the longitudinal axis of the staple blank is moved between vertical planes rotationally removed from each other.

2. Wire stitching mechanism according to claim 1, wherein the transporting element incorporates an inside staple forming element which when in the forming and driving position co-operates with the said outside staple former in the forming of the staple.

3. In wire stitching mechanism of the kind in which an outside staple former and a staple driver reciprocate along a common axis to form and drive staples, means for intermittently feeding wire stock along a line removed from said common axis and substantially at right-angles thereto, a transporting element adapted to receive and hold the fed wire in the line of feed, means for cutting oh? a staple blank from the fed wire, cam mechanism for moving the transporting element in timed relationship with the working cycle of the outside staple former and driver, from the feeding position in which the wire is fed and cut, into the forming position in which the blank is formed into a staple and driven into the work, said cam mechanism comprising a member connected to the transporting element and another member connected to the driver and adapted to convert a portion of the reciprocatory motion of the driver into oscillatory motion in a plane at right-angles thereto, so that the longitudinal axis of the staple blank is moved between vertical planes rotationally removed from each other.

4. Wire stitching mechanism according to claim 3 wherein the motion of the transporting element is timed in relationship with the working cycle of the staple former and driver so as to have stationary dwell periods in two end positions, one of said periods corresponding with the feeding and severing of a length of wire from stock and the other of said periods corresponding with the subsequent forming of the staple.

5. Wire stitching mechanism according to claim 3, wherein one of the members of the cam mechanism is connected to a cross-head carried by the driver, which cross-head has a cam track traversed by a crank pin and cam roller driven by a cam shaft controlling the motion of the former and driver.

6. Wire stitching mechanism according to claim 3, wherein the mechanism for actuating the transporting element comprises a barrel cam mounted for rotation with the transporting element on a common axis parallel with the line of motion of the staple driver, said barrel cam being driven by a cam roller and pin reciprocated by the said staple driver.

, 7. In wire stitching mechanism the combination of a'supporting frame, wire feeding elements disposed in said frame defining a horizontal line of feed of the wire stock, a wire cutter for cutting blank lengths of wire from said stock, an outside staple former and a staple driver reciprocated along a common vertical axis laterally removed from said line of feed, and a transporting element adapted to receive and hold the blank in the feeding position and to transport the cut off blank to the forming position in which the staple is formed and driven, said transporting element thereby performing rotational motion about a vertical axis common to the respective planes of the feeding and forming positions.

JOHN IRVING NASMITI-I.

REFERENCES CITED UNITED STATES PATENTS Name Date McClure Dec. 4, 1934 Number