Pressure limiting valve

• US 7,228,869 B2
• Filed: 10/07/2003
• Issued: 06/12/2007
• Est. Priority Date: 10/08/2002
• Status: Expired due to Fees

• Current Assignee: Bosch Rexroth AG (Robert Bosch GmbH)
• Original Assignee: Bosch Rexroth AG (Robert Bosch GmbH)
• Inventors: Wilhelm, Michael
• Primary Examiner(s): Krishnamurthy; Ramesh
• Application Number:
  US10/530,675
• Publication Number:
  US 20060037646A1
• Time in Patent Office: 1,344 Days
• Field of Search: 137/514, 137/514.3, 137/514.5, 137/540
• US Class Current: 137/514.3
• CPC Class Codes: F16K 15/063 the valve being loaded by a spring
• CPC Class Codes: F16K 17/04 spring-loaded
• CPC Class Codes: F16K 17/0433 with vibration preventing means
• CPC Class Codes: Y10T 137/785 With retarder or dashpot
• CPC Class Codes: Y10T 137/7851 End of valve forms dashpot chamber
• CPC Class Codes: Y10T 137/7929 Spring coaxial with valve

Abstract

What is disclosed is a a pressure limiting valve comprising a valve body, the axial movement of which is damped by means of a damping device. In accordance with the invention, the damping device includes a damping chamber formed on the return side, that is subjected to the system pressure acting on a pressure port.

Claims

1. Pressure limiting valve, comprising a valve body biased into a closed position, whereby a connection between a pressure port and a return port may be controlled open, and to which a damping device which includes a damping piston defining a damping chamber is associated for damping the valve body movement, characterized in that the damping chamber is formed on the return side and connected with the pressure port;

wherein the damping chamber is formed coaxial with a spring chamber accommodating a closing spring,

wherein the damping piston extends in portions thereof through an axial bore of the valve body, that opens into the damping chamber on the one hand and into a pressure port-side end face of the valve body on the other side,

wherein the valve body sealingly plunges into a damping sleeve through which the damping piston extends in portions thereof, and which forms an end-side termination of the damping chamber, and

wherein the valve body includes a radially recessed, return-aside axial protrusion which plunges into the damping sleeve.

2. The pressure limiting valve in accordance with claim 1, wherein the damping piston extends through a bottom of the damping sleeve.

3. The pressure limiting valve in accordance with claim 1, wherein the closing spring encompasses the damping sleeve.

4. The pressure limiting valve in accordance with claim 1, wherein the valve body includes a pressure port-side, radially recessed pin, in the range of which the axial bore is stepped back.

5. The pressure limiting valve in accordance with claim 4, wherein the pin has at its outer circumference longitudinal grooves where by the pressure port is hydraulically connected with the valve seat.

6. The pressure limiting valve in accordance with claim 2, wherein the closing spring encompasses the damping sleeve.

7. A pressure limiting valve, comprising a valve body biased into a closed position, whereby a connection between a pressure port and a return port may be controlled open, and to which a damping device which includes a damping piston defining a damping chamber is associated for damping the valve body movement, characterized in that the damping chamber is formed on the return side and connected with the pressure port,

wherein the damping chamber is formed coaxial with a spring chamber accommodating a closing spring,

wherein the damping piston extends in portions thereof through an axial bore of the valve body, that opens into the damping chamber on the one hand and into a pressure port-side end face of the valve body on the other side,

wherein the valve body sealingly plunges into a damping sleeve through which the damping piston extends in portions thereof, and which forms an end-side termination of the damping chamber, and

wherein the damping sleeve and/or the damping piston are supported on a set screw.

8. The pressure limiting valve in accordance with claim 7, wherein the valve body includes a pressure port-side radially recessed pin, in the range of which the axial bore is stepped back.

9. The pressure limiting valve in accordance with claim 8, wherein the pin has at its outer circumference longitudinal grooves whereby the pressure port is hydraulically connected with the valve seat.

10. The pressure limiting valve in accordance with claim 7, wherein the closing spring encompasses the damping sleeve.