Joint structure and hydraulic shock absorber

Patent metadata

Field	Value
Publication number	US-10088007-B2
Application number	US-201113701373-A
Country	US
Kind code	B2
Filing date	May 27, 2011
Priority date	Jun 1, 2010
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

In a joint structure for joining an insertion shaft that is driven to rotate to a reception side shaft having an insertion groove into which the insertion shaft is inserted so that a rotation of the insertion shaft is transmitted to the reception side shaft, a plurality of pairs of opposing side face portions are formed on an outer periphery of the insertion shaft, the insertion groove includes an axial hole that is formed to open onto an end surface of the reception side shaft and coincides with a pair of first side face portions of the side face portions, and a radial hole that is formed to penetrate the reception side shaft in a radial direction and coincides with a pair of second side face portions of the side face portions, and the axial hole and the radial hole are formed such that respective parts thereof intersect.

First claim

The invention claimed is:

1. A joint structure that joins an insertion shaft that is driven to rotate to a reception side shaft having an insertion groove into which the insertion shaft is inserted so that a rotation of the insertion shaft is transmitted to the reception side shaft, the joint structure comprising:
a pair of opposing arc-shaped portions included at the insertion shaft, the pair of opposing arc-shaped portions being formed on an outer periphery of the insertion shaft; and
a pair of opposing planar portions included at the insertion shaft, the pair of opposing planar portions being formed on the outer periphery of the insertion shaft;
the insertion groove including:
an axial hole that is formed to open roundly onto only one end surface of the reception side shaft and coincides with the pair of arc-shaped portions; and
a radial hole that is formed to penetrate the reception side shaft in a radial direction and coincides with the pair of planar portions, the radial hole having a width;
wherein the radial hole is formed such that a first distance across its width is substantially identical to a second distance from a surface of one of the pair of planar portions to a surface of another one of the pair of planar portions, the first distance being in a direction perpendicular to a longitudinal axis of the reception side shaft, the second distance being in a direction perpendicular to a longitudinal axis of the insertion shaft;

a radius of curvature of an entire inner peripheral surface of the axial hole that is substantially identical to a radius of curvature of the pair of arc-shaped portions; and
a bottom portion of the axial hole and an end portion of the radial hole overlapping with each other.

2. The joint structure as defined in claim 1 , wherein the pair of arc-shaped portions are formed as a continuation of the pair of planar portions and on an identical circumference to each other.

3. The joint structure according to claim 1 , further comprising a case to which the reception side shaft is screwed and which holds the reception side shaft to be capable of moving in an axial direction,
wherein the reception side shaft is guided by the case to move in the axial direction when the insertion shaft rotates.

4. The joint structure as defined in claim 3 , wherein the reception side shaft is an adjuster that adjusts an opening of a valve provided in a passage through which a fluid passes,
the insertion shaft is a shaft that is driven to rotate by an actuator, and
the opening of the valve is adjusted by driving the shaft to rotate using the actuator such that the adjuster is driven.

5. A hydraulic shock absorber that is interposed between a vehicle body and a vehicle axle to suppress variation in a vehicle body attitude, comprising:
an expansion and contraction member that includes a reservoir chamber partially filled with a gas, and performs an expansion and contraction operation; and
a damper provided in the expansion and contraction member to generate a damping force in accordance with the expansion and contraction operation of the expansion and contraction member,
wherein the damper includes:
a piston that is disposed in a cylinder to be free to slide and delimits an interior of the cylinder into an expansion side chamber and a contraction side chamber;
a rod formed such that a base end side thereof is fixed to a vehicle body side tube constituting the expansion and contraction member and the piston is fixed to a tip end side thereof;
a base member that is fixed to a bottom portion side of the cylinder and separates the reservoir chamber from the contraction side chamber;
a first port formed in the piston to connect the expansion side chamber to the contraction side chamber;
a second port formed in the base member to connect the reservoir chamber to the contraction side chamber;
a damping force generation portion that is provided in at least one of the first port and the second port and generates a damping force by applying resistance to a working fluid passing through the first port and the second port; and
a damping force adjustment mechanism that adjusts the damping force generated by the damping force generation portion,
the damping force adjustment mechanism including:
a passage partially formed in the rod so as to bypass the damping force generation portion;
a valve provided in the passage;
an adjuster that adjusts an opening of the valve;
an actuator that drives the adjuster; and
the joint structure as defined in claim 4 , which joins the shaft that is driven to rotate by the actuator to the adjuster, and
by adjusting the opening of the valve, the damping force generated by the damping force generation portion is adjusted.

6. The hydraulic shock absorber as defined in claim 5 , further comprising a control device connected to the actuator,
wherein the control device operates the adjuster by outputting a signal to the actuator.

7. A joint structure that joins an insertion shaft that is driven to rotate to a reception side shaft having an insertion groove into which the insertion shaft is inserted so that a rotation of the insertion shaft is transmitted to the reception side shaft, the joint structure comprising:
a plurality of pairs of opposing side face portions that are formed on an outer periphery of the insertion shaft;
wherein the insertion groove includes:
an axial hole that is formed to open onto an end surface of the reception side shaft and coincides with a pair of first side face portions of the side face portions; and
a radial hole that is formed to penetrate the reception side shaft in a radial direction and coincides with a pair of second side face portions of the side face portions;

wherein the axial hole and the radial hole are formed such that respective parts thereof intersect;
wherein a case to which the reception side shaft is screwed and which holds the reception side shaft is capable of moving in an axial direction; and
wherein the reception side shaft is guided by the case to move in the axial direction when the insertion shaft rotates.

8. The joint structure as defined in claim 7 , wherein the reception side shaft is an adjuster that adjusts an opening of a valve provided in a passage through which a fluid passes,
the insertion shaft is a shaft that is driven to rotate by an actuator, and
the opening of the valve is adjusted by driving the shaft to rotate using the actuator such that the adjuster is driven.

9. A hydraulic shock absorber that is interposed between a vehicle body and a vehicle axle to suppress variation in a vehicle body attitude, comprising:
an expansion and contraction member that includes a reservoir chamber partially filled with a gas, and performs an expansion and contraction operation; and
a damper provided in the expansion and contraction member to generate a damping force in accordance with the expansion and contraction operation of the expansion and contraction member,
wherein the damper includes:
a piston that is disposed in a cylinder to be free to slide and delimits an interior of the cylinder into an expansion side chamber and a contraction side chamber;
a rod formed such that a base end side thereof is fixed to a vehicle body side tube constituting the expansion and contraction member and the piston is fixed to a tip end side thereof;
a base member that is fixed to a bottom portion side of the cylinder and separates the reservoir chamber from the contraction side chamber;
a first port formed in the piston to connect the expansion side chamber to the contraction side chamber;
a second port formed in the base member to connect the reservoir chamber to the contraction side chamber;
a damping force generatio

Assignees

• Mochizuki Takahisa
• Amano Yuuki
• Kyb Corp

Inventors

• Mochizuki Takahisa
• Amano Yuuki

Classifications

• F16D1/02

  for connecting two abutting shafts or the like · CPC title

• F16F9/14 Primary

  Devices with one or more members, e.g. pistons, vanes, moving to and fro in chambers and using throttling effect · CPC title

• Y10T403/70

  Interfitted members · CPC title

• F16D1/101 Primary

  without axial retaining means rotating with the coupling · CPC title

• F16F2226/04

  Assembly or fixing methods; methods to form or fashion parts · CPC title