Arrangement for a lock cylinder for a blocking cylinder

The invention relates to an arrangement for a fluid-driven lock cylinder for the actuation of moving parts such as slides, cores and corresponding units on press tools and injection moulding tools for metal or plastic materials. A piston is accommodated in a displaceable fashion in a piston cylinder. A divided ring forms an end stop for the piston. The stop ring exhibits a maximum diameter which exceeds the diameter of the piston. An inclined external axial part of the stop ring forms a stop for making contact with a counter-pressure part of the piston cylinder. The counter-pressure part is inclined to a degree corresponding to the inclination of the end stop on the stop ring.

The present invention relates to an arrangement for a fluid-driven lock
 cylinder for the actuation of moving parts such as slides, cores and
 corresponding units on press tools and injection moulding tools for metal
 or plastic materials, comprising a piston accommodated in a displaceable
 fashion in a piston cylinder, in conjunction with which a divided ring
 forms an end stop for the piston.
 Previously disclosed arrangements of the aforementioned kind cannot be
 manufactured and installed in a simple fashion so as to function in an
 effective and safe manner.
 The principal object of the present invention is thus, in the first
 instance, to solve said problem by simple and efficiently functioning
 means.
 Said object is achieved by means of an arrangement in accordance with the
 present invention, which is characterized essentially in that the stop
 ring exhibits a maximum diameter which exceeds the diameter of the piston,
 and in that an inclined outer axial part of the stop ring forms a stop for
 making contact with a counter-pressure part of the piston cylinder, in
 conjunction with which the counter-pressure part is inclined to a degree
 corresponding to the inclination of the end stop on the stop ring.

An arrangement 1 for a lock cylinder 3 driven by a fluid such as oil 2 or
 air 2.sup.1, for the actuation of moving parts 4 such as slides, cores and
 a corresponding unit on a press tool or an injection moulding tool 5 for
 metal or plastic materials, comprises a piston 6 accommodated in a
 displaceable fashion in a piston cylinder 7. In conjunction with this, a
 ring 8 forms an end stop for the piston 6.
 In accordance with the invention, said stop ring 8 exhibits a maximum
 diameter D which exceeds the diameter d of the piston 6. An inclined
 external axial part 9 of the stop ring 8 forms a stop for making contact
 with an inclined counter-pressure part 10 of the piston cylinder 7. The
 counter-pressure part 10 is inclined in this case to a degree
 corresponding to the inclination of the end stop 9 on the stop ring 8.
 Said ring 8 is formed by at least two, but preferably more segment-forming
 ring parts 8A, 8B . . . 8n, for example five pieces as in the present
 example. Said ring parts 8A-8n are held together at mutually touching end
 parts 8.sup.1, 8.sup.2 . . . 8.sup.n and are guided in a direction towards
 11 and away from 12 one another by means of a guide pin 13. Said guide pin
 13 is accommodated in tangential holes 14, 15 which extend through pairs
 of ring parts, for example 8B, 8C, as illustrated in FIG. 6. In this case,
 one of the holes 14, 15 is a so-called bottom hole 15, while the other of
 the pair of holes 14, 15 is a transcurrent hole 14.
 The ring 8 is so arranged as to be accommodated in a ring-shaped groove 17
 formed in the piston 6.
 The piston 6 is appropriately divided at its free end 6B and exhibits a
 projecting stroke-limiting end part 19 capable of being secured with a
 central screw 18, which end part is so arranged as to make the piston 6
 higher in order to strike the top 20 of the cylinder 7 earlier.
 Said securing screw 18 is accommodated in a central hole 21, which also
 extends into a piston rod 22.
 The piston 6 accommodates an o-ring seal 24 in a ring-shaped groove 23, and
 a means 26 for checking self-actuation in the form of a sprung,
 ring-shaped, divided 27 check ring 26 is accommodated in an externally
 situated ring-shaped groove 25. Said check ring 26 is so arranged as to be
 capable of springing apart and being accommodated in a wider ring-shaped
 accommodating part 28 of the piston cylinder 7.
 Present here is an inclined part 29, 30 of both the check ring 26 and the
 accommodating part 28, enabling them to interact and pass down into the
 internal space 31 of the piston cylinder. This check ring 26 prevents the
 piston 6 from moving unintentionally in its outer position I, as
 illustrated in FIG. 3.
 The piston 6 exhibits an inclined part 6A for the purpose of forming said
 ring-shaped groove 17 therein, together with a wider space 32 in a
 cylinder housing 33 accommodating said piston cylinder 7; see FIG. 7.
 The stop ring 8 exhibits an internally conical hole 34, in which said
 conical part 6A of the piston 6 can be accommodated.
 Finally, the inclined external axial counter-pressure part 10 is formed by
 the end edge of a part 7 of the composite piston cylinder 3.
 The function of the lock cylinder illustrated by way of example in FIGS. 7
 and 8 remains the same, regardless of the driving fluid 2, 2.sup.1, which
 is supplied to either side of the piston 6, and resembles that of
 conventional piston cylinders.