| 摘要 |
<p>In gas springs, shock absorbers and the like, the cylinder member may be provided with an interconnection groove on its internal face. This groove is to interconnect two working chambers on both sides of a piston member movably received within the cylinder member. This interconnection groove is produced by a roller member introduced into the cavity of the cylinder member and having an axis substantially perpendicular to the axis of the cylinder member. The roller member has an annular elevation on its circumferential surface which is to engage the internal face of the cylinder member. A support face profiled according to the profile of the external face of the cylinder member is brought into contact with the external face of the cylinder member. The elevation of the roller member is angularly aligned with a metal receiving groove of the support face. The roller member is hereupon radially pressed against the internal face of the cylinder member and axially moved corresponding to the axial length of the interconnection groove to be obtained. So, the interconnection groove is generated by an embossing action and the metal corresponding to the interconnection groove being obtained is urged to flow into the metal receiving groove.</p> |
