Self-corrective vehicle shock absorber

• US 6,345,705 B1
• Filed: 04/28/2000
• Issued: 02/12/2002
• Est. Priority Date: 04/28/2000
• Status: Expired due to Fees

• Current Assignee: Philip W. Tremblay
• Original Assignee: Philip W. Tremblay
• Inventors: Tremblay, Philip W.
• Primary Examiner(s): Oberleitner, Robert J.
• Assistant Examiner(s): Williams, Thomas J.
• Application Number:
  US09/560,602
• Time in Patent Office: 655 Days
• Field of Search: 188/378, 188/380, 188/275, 188/318, 188/316, 188/266.1, 188/266.2, 188/266.3, 188/266.4, 267/64.11, 267/136
• US Class Current: 188/266.2
• CPC Class Codes: F16F 9/504 Inertia , i.e. acceleration,-sensitive means

Abstract

A shock absorber which is responsive to changes in inertia from turning, accelerating or stopping, the change in inertia blocking flow of damping fluid in the normal reactive direction and allowing flow in the opposite direction, the flow in the opposite or corrective direction being propelled by road surface features, such that the shock absorber will level the vehicle and over-correct against the effects of the inertia. Piston travel in the corrective direction is limited as the piston approaches either end of the cylinder by providing a flow path around the piston to prevent the piston contacting the end of the cylinder.

Claims

1. In a shock absorber for a wheeled vehicle, the shock absorber comprising a cylinder containing a reciprocating rod and piston, the piston dividing the cylinder into an upper chamber and a lower chamber each containing a damping fluid and each of which expands and contracts in response to movement of the piston and a change in inertia resulting from turning, accelerating or stopping, with a flow orifice connecting the upper chamber to the lower chamber to allow transfer of damping fluid therebetween, the shock absorber further comprising:

(A) inertia sensing means to sense a change in inertia resulting from turning, accelerating or stopping;

(B) damping fluid blocking means operatively connected to said inertia sensing means, said damping fluid blocking means restricting flow of damping fluid through the flow orifice between the upper chamber and the lower chamber in the reactive flow direction when said inertia sensing means senses a change in inertia of predetermined amount, where the reactive flow direction is the normal direction of flow from the one of the upper and lower chambers which is contracting to the other of the upper and lower chambers which is expanding in response to a particular change in inertia;

(C) damping fluid delivery means communicating between said upper and lower chambers and allowing flow of damping fluid between the upper chamber and the lower chamber only in the corrective flow direction when said damping fluid blocking means has restricted flow, where the corrective flow direction is the direction opposite to the reactive direction and is flow from said upper chamber to said lower chamber when said upper chamber is expanding and from said lower chamber to said upper chamber when said lower chamber is expanding; and

(D) travel limiting means positioned near the end of said upper chamber and near the end of said lower chamber of said cylinder, each said travel limiting means providing a passageway for flow of damping fluid around said piston in either direction between said upper chamber and said lower chamber, whereby when said piston is positioned adjacent said travel limiting means said piston is able to move normally in either direction in response to road conditions.

2. The device of claim 1, where said damping fluid delivery means comprises an upper one way valve and a lower one way valve positionable in the flow aperture, said upper one way valve allowing flow from the lower chamber to the upper chamber when said damping fluid blocking means is restricting flow of damping fluid from the upper chamber to the lower chamber, and said lower one way valve allowing flow from the upper chamber to the lower chamber when said damping fluid blocking means is restricting flow from lower chamber to the upper chamber.

3. The device of claim 1, where said inertia sensing means comprises a pendulum weight.

4. The device of claim 1, where said inertia sensing means comprises an electronic sensor.

5. The device of claim 1, where the travel limiting means opens said damping fluid blocking means to allow flow of damping fluid through the flow orifice between the upper chamber and the lower chamber in the reactive flow direction when said piston reaches a predetermined limit of travel.

6. The device of claim 1, further comprising a one way pressure relief valve mounted in the piston, the one way pressure relief valve allowing flow from the lower chamber to the upper chamber under high pressure conditions above a predetermined limit.

7. The device of claim 1, where the flow orifice is a conduit external to the cylinder, and where said damping fluid blocking means and said damping fluid delivery means communicate with said conduit, said damping fluid delivery means comprising an upper one way check valve and a lower one way check valve, said upper one way valve allowing flow from the lower chamber to the upper chamber when said damping fluid blocking means is restricting flow of damping fluid from the upper chamber to the lower chamber, and said lower one way valve allowing flow from the upper chamber to the lower chamber when said damping fluid blocking means is restricting flow from lower chamber to the upper chamber, and said damping fluid blocking means comprising means to close one of either said upper one way check valve and said lower one way check valve.

8. The device of claim 7, further comprising a pair of one way pressure relief valves mounted in the piston to allow flow of damping fluid between the upper chamber and the lower chamber in the reactive direction when the piston reaches a predetermined limit of travel.

9. The device of claim 7, further comprising a pair of branch conduits, each of said pair of branch conduits connecting said external conduit to one of the upper chamber and the lower chamber, where the piston may be positioned between said external conduit and one of said pair of branch conduits such that damping fluid may flow freely between the upper chamber and lower chamber.

10. The device of claim 1, where said damping fluid blocking means comprises a pair of solenoid valves controlled by said inertia sensing means.

11. The device of claim 1, further comprising a one way pressure relief valve communicating with said external conduit which allows flow from the lower chamber to the upper chamber under high pressure conditions above a predetermined limit.

12. The device of claim 1, further comprising a restrictive flow orifice positioned within each of said branch conduits, where said restrictive flow orifice remains open and reduces the flow of said damping fluid between said upper chamber and said lower chamber.

13. The device of claim 1, where said travel limiting means comprises a groove cut into the interior wall of said cylinder and extending in the axial direction a distance greater than the height of said piston.

14. The device of claim 1, where said travel limiting means comprises multiple grooves cut into the interior wall of said cylinder and extending in the axial direction a distance greater than the height of said piston.

15. The device of claim 1, where said travel limiting means comprises a conduit mounted onto said cylinder and having a pair of openings into either said upper chamber or said lower chamber, where the distance separating said pair of openings is greater than the height of said piston.

16. The device of claim 1, where said cylinder comprises an inner wall and an outer wall defining a flow path and where said travel limiting means comprises a pair of openings positioned in said inner wall of either said upper chamber or said lower chamber, where the distance separating said pair of openings is greater than the height of said piston.