Abstract:
A practice of severing a length of chain wherein the chain is supported and an interior link of the chain is severed at the link portion which passes through the central opening of an immediately adjacent link.

Description:
BACKGROUND OF THE INVENTION 
     This invention pertains to jewelry manufacture and, in particular, to the manufacture of jewelry chains. 
     Jewelry chains typically comprise a succession of chains links, with the end links of the chain being adapted to connect to a latch for latching the chain together. Typically, the latch comprises loops connected to each end link, one loop then being provided with a latching member which can detachably connect to the other loop. 
     The interior chain links are typically annular in configuration with the interior of the loop annulus defining the link open area. Each interior link has first and second courses which strongly couple with the preceding and succeeding chain links, respectively. The first course extends through the open area of the preceding link from one side of that link to the other side and the second course extends through the open area of the succeeding link from one side of that link to the other side. The open area of each interior link thus contains the strongly coupled first course of the succeeding link and the strongly coupled second course of the preceding link. 
     In the manufacture of chains of the above type, a section of chain is pulled from a chain roll past a severing location to a stop member. The distance between the severing location and the stop member represents the desired chain length. At the severing location, a cutting edge is passed transverse to the chain links severing same. 
     While the above procedure results in a chain of desired length, the cut end of the chain and the cut end of the chain roll are not usually in condition for immediate processing. More particularly, the last link of the chain and the first link of the roll are strongly coupled to and, therefore, retain the second course and the first course, respectively, of a cut link. These link courses must, therefore, be removed before a latch can be attached to the chain and before the chain roll can be unrolled to provide the next chain length. 
     Generally, removal of the retained link courses is effected by a hand reaming operation. As can be appreciated, such a procedure is exceedingly difficult and time-consuming and significantly slows down the overall production process. This is particularly true in the production of flat chain, since with flat chain the link courses are tightly held by the respective end links. 
     It is therefore a broad object of the present invention to provide a method and apparatus for severing chain which is improved over prior art practices. 
     It is a further object of present invention to provide a method and apparatus for severing chain which is more rapid and requires less manpower than prior art practices. 
     SUMMARY OF THE INVENTION 
     In accordance with the principles of the present invention the above and other objects are realized in a practice wherein the chain to be severed is supported and the supported chain then severed at a first or second course or link portion of a chain link. 
     In the present practice, severing is thus effected at a course of a chain link (i.e., first or second course or link portion) which is strongly coupled to an adjacent end link. As a result, separation of the cut link from such adjacent end link occurs readily without the need of significant further processing. The chain forming procedure is, therefore, greatly simplified and an overall more rapid operation results. 
     In the embodiment of the invention to be disclosed hereinafter, severing occurs at a first course or link portion of a link and at a second course or link portion of the same link or a succeeding link of the supported chain section. This results in both the end link of the cut chain and the end link of the chain supply being left free of cut links. Furthermore, in this embodiment, the supported chain is engaged by means which functions to hold the chain as it is being severed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above and other features and aspects of the present invention will become more apparent upon reading the following detailed description in conjunction with the accompanying drawings, in which: 
     FIG. 1 illustrates a die press incorporating a chain severing apparatus in accordance with the invention; 
     FIG. 2 shows a plan view of the lower section of the press of FIG. 1; 
     FIG. 3 illustrates the chain severing apparatus of the invention in greater detail; 
     FIG. 4 illustrates an exploded view of a section of chain; 
     FIGS. 5 and 6 show the severing apparatus in its operating sequence of first engaging the chain and then servering same; and 
     FIG. 7 illustrates the bottom section of the severing apparatus showing the severed chain link. 
    
    
     DETAILED DESCRIPTION 
     In FIG. 1, a conventional pneumatic press 1 incorporates a chain servering apparatus 2 in accordance with the present invention. The press 1 includes a pneumatic supply system 3 which operates a ram 4 to which is mounted an upper platen 5. The platen 5 is slidably mounted on a guide 6 which extends between the upper platen and a lower platen 7. The lower platen is mounted to the press frame 9 via threaded screw 11. 
     Chain 12 to be severed into specified lengths is conveyed from a chain roll 13 (see, FIG. 2) over a front guide roller 14 forward of the press 1 onto a chain entry track 15 having laterally spaced guide members 15a and 15b. A clamp assembly 16 follows the guide members 15a and 15b. Forward of the assembly 16 the track 15 seats in a recess 31 at the front end of the bottom section 2a of the severing apparatus 2. A chain exit track 17 extends outwardly of a second recess 32 at the back end of the section 2a. Along the track 17 a stop member 18 is slidably mounted to permit adjustment of the length of chain to be severed. 
     The severing apparatus 2 of the invention is shown in greater detail in FIG. 3. The apparatus comprises a lower section 2a having front and rear support members 33 and 34 and opposing side support members 35 and 36. These members when bolted together via screws 37 support a lower removable severing assembly 38. The assembly 38 comprises a block or plate 38a which supports front and rear guide plates 38b and 38c for guiding the central section 12c of the chain length supported on the severing section 2a. A locating pin 38d depends upwardly from the block slightly above the block surface and is supported in a first bore 38e. Two further bores 38f and 38g are situated immediately adjacent to and on opposite sides of the pin 38d. Slots 38h and 38pass through the plate 38c and into the block 38a. The function of the pin 38d, the bores 38f and 38g and the slots 38h and 38i will become apparent from the discussion below. 
     The upper section 2b of the severing apparatus also comprises front (not visible) and rear plates 39 and 41 and opposing side plates 42 and 43 which when bolted support an upper removable severing assembly 44. Assembly 44 includes a block 44a having bores 44f and 44g on opposite sides of a block position 44d which aligns with the bore and pin 38e and 38d. The bores 44f and 44g support slender severing rods 44b and 44c having severing edges 44j and 44k which extend outward of the block 44a. 
     Cylindrical rods 44l and 44m depend outwardly from slots 44h and 44i in block 44a, the former rods and slots being in alignment with the mating slots 38h and 38i of the block 38a. A plate 44e is resiliently supported by springs 44n and 44o which are arranged in encircling relationship with rods 44l and 44m, respectively. These rods pass through passages (not visible) 44p and 44q in plate 44e and extend slightly below the plate bottom. Severing rods 44b and 44c likewise extend into passages 44r and 44s of the plate 44e, these rods being slightly above the plate bottom. 
     FIG. 4 shows in exploded fashion a number of links 101-105 of the chain section 12c. As can be seen, each link is of annular configuration having an open area 110 defined by the inner annular surface of the link. Each link includes a first course or link portion 111 which strongly couples with the preceding link and a second course or link portion 112 which strongly couples with the succeeding link. Each first course or link portion 111, moreover, extends through the open area 110 of the respective preceding link from the front to the rear side of that link, while each second course or link portion 112 extends through the open area 110 of the succeeding link from the front to the rear side of that link. The open area 110 of each link is thus occupied by first and second courses of the succeeding and preceding links. 
     In accordance with the present invention, it has been recognized that severing of the chain section 12c to provide end links for the resultant chain and for the chain roll which are free of cut links can be realized by severing a link of the section 12c at its first course or link portion 111 (e.g., link 103 at A) and by severing the same link or a suceeding link at its second course or link portion (e.g., the link 103 at B). This is so because the strongest coupling between links and link retention occurs at these link courses. 
     Accordingly, the positioning of the severing surfaces 44j and 44k in block 44a is such that the surface 44j is aligned with the first course of a link of the section 12c and the surface 44k with a second course of the same or a succeeding link of such section. In the present illustrative case, the surfaces are aligned with the first and second courses of the same link, i.e., link 103, as above described. In general, however, whether the surface 44k aligns with the second course of the same or succeeding link will depend upon the particular characteristics (thickness, etc.) of the chain being cut. If a succeeding link is to be cut, it is preferable that it be as close as possible to the first cut link, since this will minimize discarded chain (i.e., chain between the first and second cut links). 
     The above-discussed positioning of the severing surfaces 44g and 44k, is obtained in the embodiment of FIG. 3 by situating the slots 38f and 38g at preselected distances relative to the pin 38d. In particular, such preselected distances are such that with the pin 38d seated in the recess between first and second courses occupying the open area 110 of a link (i.e., the link 103 in the present case), the slots 38f and 38g align, respectively, with the first course of a link adjacent the pin (i.e., the link 103 in the present case) and with the second course of that link or a succeeding link. Situating slots 38f and 38g at such preselected positions, in turn, situates the corresponding slots 44f and 44g and, therefore, the severing surfaces 44j and 44k thereat. 
     Operation of the severing apparatus 2 is illustrated by FIGS. 5-7. More particularly, the free end of the chain 12 is first pulled from the roll 13 over the track 15, past the severing apparatus 2 and over the track 17 to the stop 18. This places the chain section 12c on the block 38a. The chain is then moved slightly back and forth until the pin 38d seats in the recess between the first and second link courses. This aligns the severing surfaces 44j and 44k as above-described. 
     The ram 4 then moves the upper platen and, therewith, the upper section 2a downward towards the section 2b. This downward movement brings the rods 441l and 44m into the slots 38h and 38i, thereby ensuring correct alignment of the severing surfaces 44j and 44k and their supported rods with the slots 38f and 38g. 
     The plate 44e then engages the plates 38b and 38c and the chain section 12c. The plate is thereupon urged upward against the springs 44n and 44o and forcefully holds the chain. The rods 44b and 44c thereafter pass out of the plate slots and engage, in the present case, the first and second courses of 111 and 112 of link 103 with sufficient force to sever these link courses. The rods then continue downward pushing the severed link courses 111 and 112 into the bores 38f and 38g, which are then also entered by the rods. 
     Movement of the ram 4 in the reverse direction brings the upper section 2a back to its initial position. The chain section 12c remains on the lower section 2b with the remaining pieces of link 103 now being freely removable from the preceeding and succeeding chain lengths 102 and 104. The latter link now forms the last link of the cut chain and has an open area previously occupied by the second course 112 of the severed link 103. This open area enables direct receipt by the chain of a ring of a latching assembly. Moreover, the link 102 now serves as the first link of the chain roll. As a result, the roll can now be immediately used to cut the next chain length, since the link 102 is free of the cut link and also has an open area previously occupied by the first course 111 of the severed link 103 for receipt of a ring of a latching assembly. 
     As can be appreciated, the present severing apparatus provides a rapid and relatively simple mechanism for severing chains to desired chain lengths, while at the same time providing terminal links for the chain lengths suitable for immediate attachment of latching rings. Costly and lengthy manual reaming procedures are, therefore, avoided resulting in a considerable overall savings. 
     In all cases, it is understood that the abovedescribed arrangements are merely illustrative of the many possible specific embodiments which represent applications of the present invention. Numerous and varied other arrangements can readily be devised in accordance with the principles of the present invention without departing from the spirit and scope of the invention.