Hydraulic cylinder mechanism

• US 4,747,614 A
• Filed: 03/12/1987
• Issued: 05/31/1988
• Est. Priority Date: 03/12/1986
• Status: Expired due to Fees

• Current Assignee: Nippondenso Co., Ltd. (DENSO Corporation)
• Original Assignee: Nippondenso Co., Ltd. (DENSO Corporation)
• Inventors: Kuroyanagi, Masatoshi, Murakami, Fumiaki, Majima, Youzou, Matsui, Kazuma
• Primary Examiner(s): Bertsch, Richard A.
• Application Number:
  US07/025,275
• Time in Patent Office: 446 Days
• Field of Search: 280/661, 280/701, 280/91, 280/702
• US Class Current: 280/86.75
• CPC Class Codes: B60G 2200/10 Independent suspensions
• CPC Class Codes: B60G 2200/142 with a single lateral arm, e.g. MacPherson type
• CPC Class Codes: B60G 2200/1442 including longitudinal rods
• CPC Class Codes: B60G 2200/46 camber angle
• CPC Class Codes: B60G 2200/462 Toe-in/out
• CPC Class Codes: B60G 2200/4622 Alignment adjustment
• CPC Class Codes: B60G 2202/40 Type of actuator
• CPC Class Codes: B60G 2202/413 Hydraulic actuator
• CPC Class Codes: B60G 2204/14 Mounting of suspension arms
• CPC Class Codes: B60G 2204/143 on the vehicle body or chassis
• CPC Class Codes: B60G 2204/42 Joints with cam surfaces
• CPC Class Codes: B60G 2204/61 Adjustable during maintenance
• CPC Class Codes: B60G 2204/62 Adjustable continuously, e.g. during driving
• CPC Class Codes: B60G 2206/111 of adjustable length
• CPC Class Codes: B60G 7/003 of adjustable length
• CPC Class Codes: B60G 7/006 Attaching arms to sprung or unsprung part of vehicle, characterised by comprising attachment means controlled by an external actuator, e.g. a fluid or electrical motor B62D7/146 takes precedence
• CPC Class Codes: B60G 7/02 Attaching arms to sprung part of vehicle B60G7/006 takes precedence
• CPC Class Codes: B62D 17/00 Means on vehicles for adjusting camber, castor, or toe-in

Abstract

The hydraulic cylinder mechanism has a main piston which has a piston portion, two sub-pistons which is so located that the sub-pistons can hold the piston portion, control pressure chambers which are formed between the sub-piston and the piston portion, and holding pressure chambers which are formed at behind of the sub-piston. The hydraulic cylinder mechanism controls automotive rear wheel alignment when the main piston moves axially according to the pressure in the control pressure chambers and can maintain its neutral position when the pressure in the holding chamber is applied to the sub-piston so that holds the piston portion.

Claims

1. A hydraulic cylinder mechanism for controlling the displacement of swing means which swingably supports an automotive wheel to an automotive body in order to control wheel alignment comprising:

a cylinder member connected to one of said body and said wheel;

a main piston arranged slidably in said cylinder member and connected to another one of said body and said wheel;

a piston portion formed in said main piston and made movable together with said main piston;

two cylindrical sub-pistons surrounding said main piston and clamping said piston portion from both sides of said piston portion in said cylinder member;

control pressure chambers formed between said sub-pistons and said piston portion so that said piston portion is driven in accordance with the pressure in said control pressure chambers; and

holding pressure chambers formed at back of said sub-pistons so that said piston portion is held in a predetermined position by the pressure in said holding pressure chambers.

2. A hydraulic cylinder mechanism according to claim 1, wherein said swing means includes an arm portion arranged between said wheel and said automotive body and displaces the whole length of said arm portion.

3. A hydraulic cylinder mechanism according to claim 1, wherein said swing means includes an arm portion arranged between said wheel and said automotive body and displaces a connected position of said arm portion and said body.

4. A hydraulic cylinder mechanism according to claim 1, further comprising an electromagnetic valve for switching and controlling the control oil pressures supplied to both the first control pressure chamber formed between one of said sub-piston and said piston portion and the second control pressure chamber formed between the other sub-piston and piston portion.

5. A hydraulic cylinder mechanism according to claim 1, wherein the receiving areas of said control pressure chambers to which the control pressure is applied in order to move said main piston are larger than those of the holding pressure chambers to which the control pressure is applied in order to move said sub-piston.