Shock absorber for vehicle

Patent metadata

Field	Value
Publication number	US-11148500-B2
Application number	US-201916570111-A
Country	US
Kind code	B2
Filing date	Sep 13, 2019
Priority date	May 7, 2019
Publication date	Oct 19, 2021
Grant date	Oct 19, 2021

Abstract

A shock absorber for a vehicle may include a flow path provided in a rod valve to allow an oil film to be formed between a cylinder and the rod valve during relative movements of a strut rod and the cylinder, and the oil film is used to prevent friction from occurring between the cylinder and the rod valve during steering.

First claim

What is claimed is:

1. A shock absorber apparatus for a vehicle, the shock absorber apparatus comprising:
a cylinder configured to be connected with a steering knuckle, and filled with fluid in the cylinder;
a strut rod, an end portion of which is slidably inserted into the cylinder; and
a rod valve fixedly mounted on the end portion of the strut rod, the rod valve having a flow path guiding a flow of the fluid while the strut rod and the cylinder relatively move to each other,
wherein the flow path is provided to be fluidically-connected to an external circumferential surface of the rod valve so that an oil film is formed between the external circumferential surface of the rod valve and an internal wall surface of the cylinder while the strut rod and the cylinder relatively move to each other,
wherein the flow path includes:
a first flow path formed to pass through an upper surface of the rod valve fixed on the strut rod and fluidically-connected with a fluid space; and
a second flow path formed to pass through a lower surface of the rod valve fixed on the strut rod and fluidically-connected with the fluid space,

wherein a valve groove having a cross section of a concave shape is provided on the external circumferential surface of the rod valve along a circumferential direction of the rod valve,
wherein a first end of the first flow path is positioned on the upper surface of the rod valve and a second end of the first flow path is positioned on a first side surface of the valve groove,
wherein a first end of the second flow path is positioned on the lower surface of the rod valve and a second end of the second flow path is positioned on a second side surface of the valve groove, and
wherein the second end of the first flow path and the second end of the second flow path are arranged symmetrical to each other based on a center of a circumference of the rod valve.

2. The shock absorber apparatus of claim 1 , further including:
an upper seal and a lower seal mounted on the external circumferential surface of the rod valve,
wherein the upper seal and the lower seal are spaced to each other with the fluid space along a longitudinal axis of the strut rod, and
wherein the upper seal and the lower seal are provided to slidably contact the internal wall surface of the cylinder.

3. The shock absorber apparatus of claim 2 ,
wherein a diameter of the rod valve is provided to be smaller than a diameter of the internal wall surface of the cylinder, so that the fluid space is defined between the external circumferential surface of the rod valve, the internal wall surface of the cylinder, the upper seal, and the lower seal, and
wherein the fluid space fluidically-communicates with the flow path to form the oil film.

4. The shock absorber apparatus of claim 3 ,
wherein diameters of the upper seal and the lower seal are greater than the diameter of the rod valve and substantially equal to the diameter of the internal wall surface of the cylinder to form the fluid space so that the upper seal and the lower seal are slidably engaged to the internal wall surface of the cylinder.

5. The shock absorber apparatus of claim 4 ,
wherein while the strut rod and the cylinder relatively move to each other, the fluid communicates with the fluid space to form the oil film in the fluid space.

6. The shock absorber apparatus of claim 4 ,
wherein the cylinder includes an upper chamber and a lower chamber,
wherein the upper chamber is positioned above the upper seal and fluidically-connected to the first flow path, and
wherein the lower chamber is positioned below the lower seal and fluidically-connected to the second flow path.

7. The shock absorber apparatus of claim 6 ,
wherein when the strut rod moves relatively toward a lower side of the cylinder, a fluid located in the lower chamber is introduced into the second flow path and discharged to the fluid space to have the oil film formed in the fluid space, and then flows through the first flow path to the upper chamber.

8. The shock absorber apparatus of claim 4 ,
wherein the valve groove is positioned between the upper seal and the lower seal along the longitudinal axis of the strut rod.

9. A shock absorber apparatus for a vehicle, the shock absorber apparatus comprising:
a rod valve fixedly mounted on an end portion of a strut rod slidably mounted in a cylinder; and
a flow path provided on the rod valve, through which fluid flows,
wherein the flow path is provided in an upper surface, an external circumferential surface, and a lower surface of the rod valve to form an oil film in a fluid space between an inner wall surface of the cylinder and the external circumferential surface of the rod valve by a fluid discharged to the external circumferential surface of the rod valve,
wherein the flow path includes:
a first flow path formed to pass through an upper surface of the rod valve fixed on the strut rod, and fluidically-connected with the fluid space; and
a second flow path formed to pass through a lower surface of the rod valve fixed on the strut rod, and fluidically-connected with the fluid space,

wherein a valve groove having a cross section of a concave shape is provided on the external circumferential surface of the rod valve along a circumferential direction of the rod valve,
wherein a first end of the first flow path is positioned on the upper surface of the rod valve and a second end of the first flow path is positioned on a first side surface of the valve groove,
wherein a first end of the second flow path is positioned on the lower surface of the rod valve and a second end of the second flow path is positioned on a second side surface of the valve groove, and
wherein the second end of the first flow path and the second end of the second flow path are arranged symmetrical to each other based on a center of a circumference of the rod valve.

10. The shock absorber apparatus of claim 9 ,
wherein the fluid is discharged through the flow path to the external circumferential surface of the rod valve while the strut rod and the cylinder relatively move to each other.

11. The shock absorber apparatus of claim 9 ,
wherein the flow path is fluidically-connected to a first cylinder space positioned on an upper side of the rod valve and with a second cylinder space positioned on a lower side of the rod valve.

12. The shock absorber apparatus of claim 9 , further including:
an upper seal and a lower seal mounted on the external circumferential surface of the rod valve and slidably contacting the internal wall surface of the cylinder,
wherein the upper seal and the lower seal are spaced to each other along a longitudinal axis of the strut rod and the external circumferential surface of the rod valve and the internal wall surface of the cylinder are spaced to each other, to form the fluid space between the upper seal, the lower seal, the external circumferential surface of the rod valve and the internal wall surface of the cylinder.

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp

Inventors

• Shim Hyung Shik

Classifications

• B60G2204/16

  Mounting of vehicle body on chassis · CPC title

• B60G2202/24

  Fluid damper · CPC title

• F16F9/3481

  characterised by shape or construction of throttling passages in piston (F16F9/344 takes precedence) · CPC title

• B60G2202/12

  Wound spring · CPC title

• B60G2202/312

  The spring being a wound spring · CPC title