IP Library › Granted Patent US 7,171,888
Granted Patent B2
US 7,171,888 · App. 11/148,514 · Granted Feb 6, 2007

Hydraulic cylinder

Assignee: TRW Automotive GmbH
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Quick Facts
Patent No.
US 7,171,888
App. No.
11/148,514
Granted
Feb 6, 2007
Kind
B2
Abstract

A hydraulic cylinder comprising a cylinder, a piston which is adjustable in the cylinder, and at least one pressure connection which is disposed in the vicinity of an end position of the piston and through which a pressure fluid can be introduced into the cylinder, is characterized in that the piston is provided with a valve element which can cooperate with the pressure connection, in order to cover the pressure connection when the piston approaches its end position, and in order to uncover the pressure connection when pressure fluid is introduced into the cylinder.

Claims (12)

1. A hydraulic cylinder comprising:

a cylinder;

a piston which is adjustable in the cylinder; and

at least one pressure connection which is disposed in the vicinity of an end position of the piston and through which a pressure fluid can be introduced into the cylinder;

wherein the piston is provided with an elastically deformable part forming a valve element which cooperates with the pressure connection, in order to cover the pressure connection when the piston approaches its end position, and in order to uncover the pressure connection when pressure fluid is introduced into the cylinder, such that when pressure fluid is introduced into the cylinder, the elastically deformable part of the valve element is deformed radially inwardly and away from the at least one pressure connection, thereby creating an enlarged flow path for incoming pressure fluid between an inner wall of the cylinder and the deformed part of the valve element.

2. The hydraulic cylinder as claimed in claim 1 , wherein the elastically deformable part forming the valve element is an apron.

3. The hydraulic cylinder as claimed in claim 2 , wherein the apron is integrally formed with the piston.

4. The hydraulic cylinder as claimed in claim 2 , wherein the piston has a multi-part design and has a pot-like end piece, which is provided with the apron.

5. The hydraulic cylinder as claimed in claim 1 , wherein the piston is provided with an annular groove, which by means of a passage is connected with that side of the piston to which the pressure fluid is applied.

6. The hydraulic cylinder as claimed in claim 1 , wherein the piston is provided with a piston ring.

7. The hydraulic cylinder as claimed in claim 1 , wherein the piston is provided with at least one sealing rib integrally formed with the same.

8. The hydraulic cylinder as claimed in claim 1 , wherein a limit stop is provided, which prevents the valve element from resting against an end face of the cylinder when the piston is in its end position.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 9, 2005
From: BOECKER, MARTIN
To: TRW AUTOMOTIVE GMBH
Reel/Frame 016681/0790 →
Priority Claims (1)
DE 202 19 451 · Dec 13, 2002 · national
Continuity (2)
Continuation PCTEP200301408400 · Dec 11, 2003
Related Publication 20050226750A1 · Oct 13, 2005