Catch at a pressring

[0002] The invention is relative to a catch (clasp) on a pressring (shaping ring) with several cheek plate elements connected to each other in an articulated fashion, with a coupling element with which the cheek plate elements adjacent to a closed position and comprising a coupling bolt for a closing device can be provisionally connected.

[0003] A clasp of this type is known in the state of the art from EP 0671984. It comprises a coupling element which has a first coupling shackle articulated to a cheek plate element and a second coupling shackle connected to the other cheek plate element. These two coupling shackles can be connected by a coupling bolt which engages into both and which must be rotated to close the coupling member. In the coupled state, the coupling member is designed to be flexible.

[0004] The present invention creates a clasp of the cited type which can be produced in a simpler and more economical manner and, in addition, is simpler to manipulate.

[0005] The present invention solves the problems of a generic clasp in that the coupling element of the present invention is a bracket [curved piece of metal] mounted so that it can pivot on its one end on the coupling bolt of the one cheek plate element and which can be connected by its other end to the other cheek plate element in such a manner that this other end is movably mounted on the other cheek plate element in the coupled position.

[0006] In the clasp according to the invention the coupling element is a bracket movably mounted on its pivotable end in the locking position on the shaping ring. During the closing of the shaping ring a shifting occurs between the bracket and the one cheek plate element of the shaping ring. This has the significant advantage that the coupling element does not have to be designed to be flexible. This can avoid expensive articulations. The bracket can be produced in a very simple manner from a rigid wire. In a preferred embodiment the bracket is a wire bracket which is essentially U-shaped when viewed in the radial direction of the cheek plate. The bracket can therefore be manufactured in a very simple manner from a piece of wire. Even the manipulating of the clasp in accordance with the invention is very simple. In order to provisionally close the shaping ring all that is necessary is to pivot the bracket into the locking position. To open it the bracket is pivoted in the opposite direction.

[0007] The manufacture is particularly simple if the bracket is mounted on the coupling bolts provided for the closing device. One of these coupling bolts serves with its projecting ends consisting of joint bolts for the bracket and other coupling bolt serves in cooperation with the bend of the bracket to determine the opening width of the shaping ring in the coupled position.

[0008] According to a further development of the invention at least one cheek plate element adjacent to the closed position comprises at least one projection with which the bracket is locked in its closed position. During the closing of the shaping ring the bracket slides along this projection. The bracket thus remains fixed during the closing of the shaping ring and can be loosened after the pressing procedure by being pivoted. Such a projection can be realized, for example, in a very economical manner as a comparatively short, formed-on cam.

[0009] The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.

[0010] In the drawings:

[0011] FIG. 1 shows a view of a shaping ring with a clasp in accordance with the invention.

[0012] FIG. 2 shows a schematic view of a known locking device.

[0013] FIG. 3 shows another view of the shaping ring with a clasp in accordance with the invention, which shaping ring is placed around a pipe shown in section here.

[0014] FIG. 4 shows a view of the shaping ring with a clasp in accordance with the invention as well as with a locking device according to FIG. 2 placed on the coupling bolt.

[0015] FIG. 5 shows another view corresponding to FIG. 3 but with a closed shaping ring.

[0016] FIG. 6 shows a view corresponding to FIG. 4 but after the shaping ring has been closed.

[0017] Shaping ring, or pressring, 2 shown in FIG. 1 comprises a central cheek plate element 6 which is pivotably connected by two symmetrically arranged joint bolts 8 to other cheek plate elements 5,7. Each cheek plate element 5,7 comprises a coupling bolt 9 and 10 on which locking device 25 shown in FIG. 2 can be set for closing shaping ring 2.

[0018] Locking device 25 is a known commercial product and comprises two levers 26 mounted on a part 27 and pivotable about joint bolts 29 by means of a drive (not shown here). The two levers 26 rest with recesses 32 on the outside of coupling bolts 9, 10. Driver rollers 30 indicated in FIGS. 4,6 attack inclined surfaces 28 of the two levers 26 and as a result pivot the two levers 26 in such a manner that recesses 32 and joint bolts 9, 10 are moved against each other. FIGS. 3,4 shows shaping ring 2 on a pipe 31 and before the locking or pressing of pipe 31. An intermediary space or locking position 4 is located between the two cheek plate elements 5,7. FIGS. 5,6 show shaping ring 2 in a locked, or closed, position. Pipe 31 or a press fitting (not shown here) is pressed around its entire circumference after the locking procedure. Front sides 18, 19 of the two cheek plate elements 5,7 are in contact, as can be seen from FIGS. 5,6.

[0019] If shaping ring 2 is placed like a saddle as shown in FIGS. 3,4 on pipe 31 for pressing it, the ring is provisionally locked at the lower ends of the two cheek plate elements 5,6 by clasp 1. This avoids having to hold massive shaping ring 2, which is made of metal and is comparatively heavy, thus leaving both hands free for operating the locking device. Clasp 1 consists essentially of bracket 3, which is preferably a wire bracket. As FIG. 3 shows, the bracket is essentially U-shaped viewed in the radial direction of shaping ring 2 and comprises two shanks 15 running essentially parallel to one another and comprises crosspiece 16. The ends of shanks 15 surround projecting end 9aof coupling bolt 9 form an articulation which permits a limited pivoting of bracket 3 about coupling bolt 9.

[0020] In FIG. 1 shaping ring 2 is open and can be placed like a saddle on a pipe 31 in order to press a press fitting (not shown here). Locking ring 2 can be provisionally closed by pivoting bracket 3 into the position shown in FIGS. 3 and 4, during which closing position 4 is present between cheek plate elements 5,7 which position is closed, as explained above, with clasping device 25. As FIGS. 3 and 4 clearly show, bracket 3 is approximately Z-shaped and in particular has an angled shape in the view according to FIG. 4. In the locking position bracket 3 rests with two essentially 90° bends 20 on projecting ends 10aof coupling bolt 10. Two comparatively short projections 17 are formed on the outside of the cheek plate element at an interval to coupling bolt 10 on which projections bracket 3 rests. Projections 17 form catch cams which bracket 3 can jump over by virtue of a resilient extension when being pivoted in and out. The positions at which projections 17 rest on bracket 3 are designated in FIG. 3 with A. Positions A together with positions B form engagement sites which are formed by bent-out sections 15cof shanks 15.

[0021] When shaping ring 2 is being closed the two shanks 15 slide between a coupling bolt 10 and a projection 17 along cheek plate element 7 and remain thereby in the engaged position. After the pressing procedure projections 17 rest at the bracket positions designated with B. Bracket 3 has a bend between the two positions A and B. After the shaping ring has been closed it therefore continues to be locked by bracket 3 and can therefore not slide off pipe 31. Locking device 25 is removed from shaping ring 2 after the pressing procedure. Shaping ring 2 can be opened again by pivoting bracket 3 counterclockwise and removed from pipe 21. Shaping ring 2 is now ready for another pressing procedure.

[0022] According to FIG. 6 bracket 3 extends over shaping ring 2 with its pivotable end 3aand can be reliably grasped on this end 3a.

[0023] While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.