Fluid pressure cylinder

Patent metadata

Field	Value
Publication number	US-10677270-B2
Application number	US-201615580124-A
Country	US
Kind code	B2
Filing date	Jun 1, 2016
Priority date	Jun 11, 2015
Publication date	Jun 9, 2020
Grant date	Jun 9, 2020

Abstract

In an interior of a cylinder tube of a fluid pressure cylinder, a piston unit is provided, which is displaced along an axial direction under the supply of a pressure fluid. The piston unit includes a disk shaped plate body, which is connected to one end of a piston rod, and a ring body connected to an outer edge portion of the plate body. The plate body is connected to the piston rod by plural second rivets, which are punched in an axial direction with respect to the piston rod.

First claim

The invention claimed is:

1. A fluid pressure cylinder comprising:
a cylinder tube;
a cover member attached to an end of the cylinder tube, which end is an axial end of the cylinder tube relative to the direction of the axis of the cylinder tube;
a piston rod extending along the axial direction in the cylinder tube, the piston rod having an axial end relative to the direction of the axis of the cylinder tube, wherein the piston rod is displaceable in the cylinder tube along the direction of the axis of the cylinder tube;
a piston dividing the interior of the cylinder tube into two cylinder chambers, wherein the piston comprises a central portion provided as an elastic plate body having a surface facing one of said two cylinder chambers, which one of said two cylinder chambers is closer to said cover member than is another of said two cylinder chambers, said surface being mounted to the axial end of the piston rod, wherein the piston further comprises an annular ring-body disposed at an outer edge portion of the plate body and configured to slide along an inner circumferential surface of the cylinder tube;
a bore in a surface of said annular ring-body that faces said one of said two cylinder chambers;
a magnet housed in said bore and having a surface exposed to said one of said two cylinder chambers;
a pin member fixing the central portion of the plate body to the axial end of the piston rod with said surface being mounted to the axial end of the piston rod,
wherein no portion of said annular ring-body extends axially beyond the central portion in a direction toward the other of said two cylinder chambers, and
wherein said central portion extends axially beyond any portion of the annular ring-body in the direction toward the other of said two cylinder chambers.

2. The fluid pressure cylinder according to claim 1 , wherein the pin member comprises a rivet that is punched with respect to the piston rod along an axial direction of the piston rod.

3. The fluid pressure cylinder according to claim 1 , wherein the pin member is punched with respect to the piston rod at a predetermined angle of inclination with respect to an axial direction of the piston rod.

4. The fluid pressure cylinder according to claim 3 , wherein a positioning member is included in a central portion of the plate body, an end of the piston rod is inserted into the positioning member and positioned coaxially therewith, and the plate body and the piston rod are connected by the pin member through the positioning member.

5. The fluid pressure cylinder according to claim 1 , further comprising, in a central portion of the plate body, a cushion member, which projects out in a direction away from the piston rod, the cushion member being fixed by the pin member with respect to the plate body, and by the cushion member being accommodated in an accommodating hole of the cover member, a displacement speed of the piston is decelerated.

6. The fluid pressure cylinder according to claim 1 , wherein the surface of said magnet that is exposed to said one of said two cylinder chambers is coplanar with the surface of said annular ring-body that faces said one of said two cylinder chambers.

7. The fluid pressure cylinder according to claim 1 , further comprising a damper provided on the cover member at a radial location corresponding to the magnet.

Assignees

• Smc Corp

Inventors

• Suzuki Yasunaga
• Fukui Chiaki
• Yaegashi Makoto

Classifications

• F15B15/1447 Primary

  Pistons; Piston to piston rod assemblies · CPC title

• F15B15/223

  having a piston with a piston extension or piston recess which completely seals the main fluid outlet as the piston approaches its end position · CPC title

• F15B15/2861

  using magnetic means · CPC title

• F15B15/1428

  Cylinders (F15B15/1438 takes precedence) · CPC title

• F15B15/1438

  Cylinder to end cap assemblies · CPC title