Damper device

Patent metadata

Field	Value
Publication number	US-10221909-B2
Application number	US-201415113777-A
Country	US
Kind code	B2
Filing date	Oct 8, 2014
Priority date	Jan 31, 2014
Publication date	Mar 5, 2019
Grant date	Mar 5, 2019

Abstract

A damper device is configured so that a piston moves in a cylinder. A seal ring member is provided to the outer periphery of the piston to device the inside of the cylinder into a first chamber and a second chamber. A transmission member is connected to the piston and can transmit external force to the piston. A cutout section is formed with a predetermined circumferential width in a first stopper surface. A communication section has an opening in an annular outer peripheral section located closer to the second chamber than the cutout section. When the seal ring member is pressed toward the first stopper surface, the seal ring member is deformed so as to partially enter the cutout section.

First claim

The invention claimed is:

1. A damper device, including:
a cylinder including a bottom portion and an opening portion;
a piston that is movable in the cylinder toward the bottom portion and the opening portion of the cylinder;
a seal ring member that is disposed on an outer circumference of the piston to abut on an inner circumference of the cylinder to thereby divide an inside of the cylinder into a first chamber and a second chamber; and
a transmission member that is connected to the piston, and is capable of transmitting an external force to the piston,
wherein the piston includes:
an annular outer circumferential portion that abuts on an inner circumference of the seal ring member;
a first stopper surface that protrudes in a radial direction of the piston from one side of the annular outer circumferential portion at a side of the first chamber to thereby restrict a movement of the seal ring member toward the first chamber in an axial direction of the piston;
a second stopper surface that protrudes in the radial direction of the piston from another side of the annular outer circumferential portion at a side of the second chamber to thereby restrict a movement of the seal ring member toward the second chamber in the axial direction of the piston;
a cutout portion that is formed on the first stopper surface and has a predetermined width in a circumferential direction of the piston; and
a communicating portion that is formed on the piston to communicate between the first chamber and the second chamber,

wherein the communicating portion includes a groove formed on the annular outer circumferential portion at a position corresponding to the cutout portion,
wherein the seal ring member is configured to be pressed toward one of the first stopper surface and the second stopper surface when the piston is moving in the cylinder,
wherein, when the seal ring member is pressed toward the first stopper surface, the seal ring member is deformed to partially get in the cutout portion,
wherein the piston further includes a seat portion which protrudes in the radial direction of the piston and the seat portion covers the cutout portion formed on the first stopper surface from the side of the first chamber, and
wherein a radial deformation suppressing portion extending in the axial direction of the piston from the second stopper surface toward the first stopper surface is formed in the groove, and a distal end of the radial deformation suppressing portion is separated from the seat portion in the axial direction of the piston.

2. The damper device of claim 1 , wherein, when the seal ring member is pressed toward the first stopper surface and the seal ring member partially gets in the cutout portion, a communication between the first chamber and the second chamber of the cylinder via the groove is opened, and
wherein, when the seal ring member is pressed toward the second stopper surface, the communication between the first chamber and the second chamber via the groove is closed by the seal ring member.

3. The damper device of claim 1 , wherein the seal ring member is disposed on the annular outer circumferential portion in a state of abutting on both of the first stopper surface and the second stopper surface.

4. The damper device of claim 1 , wherein the second stopper surface is inclined with respect to the first stopper surface.

5. The damper device of claim 1 , wherein the piston further includes a first large-diameter portion, a second large-diameter portion, and a small-diameter portion,
wherein the small-diameter portion is disposed between the first large-diameter portion and the second large-diameter portion and is recessed with respect to the first large-diameter portion and the second-large-diameter portion in the radial direction of the piston,
wherein each of the first large-diameter portion and the second large-diameter portion is larger in diameter than the small-diameter portion,
wherein an outer circumferential surface of the small-diameter portion functions as the annular outer circumferential portion,
wherein a surface of the first large-diameter portion at a side of the small-diameter portion functions as the first stopper surface and another surface of the first large-diameter portion at a side opposite to the small-diameter portion functions as the seat portion, and
wherein a surface of the second large-diameter portion at a side of the small-diameter portion functions as the second stopper surface.

6. The damper device of claim 1 , wherein, when the seal ring member is pressed toward the first stopper surface, the seal ring member protrudes toward the first chamber to penetrate into the cutout portion and the seat portion which covers the cutout portion is configured to suppress an excessive partial deformation of the seal ring member.

7. The damper device of claim 1 , wherein, as viewed along the axial direction of the piston, the second stopper surface forms a circle and the first stopper surface does not form a circle due to the cutout portion.

8. The damper device of claim 7 , wherein, as viewed along the axial direction of the piston, the seat portion forms a circle such that the seat portion covers the cutout portion from the side of the first chamber.

9. The damper device of claim 1 , wherein, when the seal ring member is pressed toward the first stopper surface, portions of the first stopper surface, which are located adjacent to the cutout portion, abut the seal ring.

10. The damper device of claim 1 , wherein, when the seal ring member is pressed toward the first stopper surface, portions of the first stopper surface, which confine the cutout portion in the circumferential direction of the piston, abut the seal ring.

11. A damper device, including:
a cylinder including a bottom portion and an opening portion;
a piston that is movable in the cylinder by an external force transmitted by a transmission member; and
a seal ring member that is disposed on an outer circumference of the piston to abut on an inner circumference of the cylinder to divide an inside of the cylinder into a first chamber and a second chamber,
wherein the piston includes:
an annular outer circumferential portion that abuts on an inner circumference of the seal ring member;
a first stopper surface that protrudes in a radial direction of the piston from one side of the annular outer circumferential portion at a side of the first chamber to restrict a movement of the seal ring member toward the first chamber in an axial direction of the piston;
a second stopper surface that protrudes in the radial direction of the piston from another side of the annular outer circumferential portion at a side of the second chamber to restrict a movement of the seal ring member toward the second chamber in the axial direction of the piston;
a cutout portion that is formed on the first stopper surface; and
a communicating portion that is formed on the piston to communicate between the first chamber and the second chamber,

wherein a portion of the seal ring member gets in and out the cutout portion in accordance with a movement of the piston in the cylinder to open and close the communicating portion,
wherein the piston further includes a seat portion which protrudes in the radial direction of the piston and the seat portion covers the cutout portion formed on the first stopper surface from the side of the first chamber, and
wherein a radial deformation suppressing portion extending in the axial direction of the piston from the second stopper surface toward the first stopper surface is formed in the groove, and a distal end of the radial deformation suppressing portion is separated from the seat po

Assignees

• Piolax Inc

Inventors

• Saito Jun

Classifications

• F16F9/368

  Sealings in pistons · CPC title

• F16J1/008

  with sealing lips · CPC title

• F16F9/3228

  of connections between pistons and piston rods · CPC title

• F16F9/0218

  Mono-tubular units (F16F9/0227, F16F9/0236, F16F9/0245 take precedence) · CPC title

• E05F5/10

  with piston brakes · CPC title