JPH071536Y2 - Variable damping force type hydraulic shock absorber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention relates to a damping force variable hydraulic shock absorber with an improved actuator mounting structure.

<< Prior Art >> For example, like a hydraulic shock absorber mounted on a suspension of a vehicle, a damping force variable mechanism is used to variably adjust the damping force according to road surface conditions such as city driving and bad road driving. A variable damping force type hydraulic shock absorber provided with is generally known.
An actuator for variably controlling the damping force varying mechanism is provided in the hydraulic shock absorber in a state of being connected to the damping force varying mechanism.

The actuator is generally mounted via an elastic body between the actuator and the shock absorber so as to be reliably supported in the shock absorber with respect to the vibration of the hydraulic shock absorber.

As this type of conventional damping force variable hydraulic buffer, for example, the one disclosed in Japanese Utility Model Laid-Open No. 60-189636 is known.

When this hydraulic shock absorber is outlined, as shown in FIG. 4, an actuator 6 mainly composed of a motor 1, a support block 2, a crown gear 3, a stopper plate 4 and an electromagnet 5 is connected to the upper end of the outer cover 7 and the underside. It is attached to the case 8. The actuator 6 is fixed by interposing an elastic body 9 such as rubber between the inner surface of the upper end wall of the outer cover 7 and the upper side surface of the under case 8 and the actuator 6.

In addition to this, there is one disclosed in Japanese Utility Model Laid-Open No. 60-191738, but in this case as well, the actuator 6 is supported by an elastic body.

<Problems to be Solved by the Invention> However, in the hydraulic shock absorber having the above structure, the elastic body 9 supporting the actuator 6 deteriorates due to heat, vibration, etc., and backlash occurs in the thrust direction and the radial direction. 6 vibrates, abnormal noise is generated and actuator 6
There is a risk of misalignment.

Further, the tightening margin may be increased in anticipation of the deterioration of the elastic body 9, but in this case, unnecessary stress is applied to the actuator 6, which may cause malfunction.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a damping force variable hydraulic shock absorber capable of reliably preventing a defect due to deterioration of a member supporting an actuator.

<Means for Solving the Problems> In order to achieve the above-mentioned object, the present invention provides a damping force variable mechanism that is provided in a piston rod to variably adjust the damping force, and the damping force provided in the outer cover. An actuator coupled to the variable mechanism for variably controlling the damping force variable mechanism; a wave washer interposed between an inner side surface of the outer cover and an upper side surface of the actuator for axially urging the actuator; It is characterized in that it is provided with a star washer which is provided on the lower side surface of the actuator and prevents the actuator from rotating by the claw portion interfering with the inner peripheral surface of the outer cover.

<Operation> The wave washer interposed between the outer cover and the upper side surface of the actuator reliably urges the actuator in the axial direction and absorbs rattling in the thrust direction without deterioration due to heat, vibration, and the like.

Also, the claws of the star washer provided on the lower side surface of the actuator interfere with the inner peripheral surface of the outer cover to prevent the actuator from rotating, which makes it easier to mount the actuator and absorbs rattling in the thrust and radial directions of the actuator. .

<< Embodiment >> An embodiment of the present invention will be described below with reference to the accompanying drawings.

The overall structure of the variable damping force type hydraulic shock absorber of the present embodiment will be outlined with reference to FIG. This damping force variable hydraulic shock absorber
It is mainly composed of a shock absorber portion 10 and an outer cover 11 to which an actuator 45 described later is attached. The shock absorber unit 10 includes a cylinder 12 filled with hydraulic fluid and a piston that divides the cylinder 12 into an upper liquid chamber 13 and a lower liquid chamber 14.
15 and the piston 15 provided on the piston 15
A damping force generating mechanism 16 that generates a damping force when sliding up and down inside the piston 12, and a piston rod 17 that extends outside the cylinder 12 and supports the piston 15 via a support shaft portion 17a.
And a damping force generation mechanism provided in the piston rod 17.
A damping force variable mechanism 18 that adjusts the bypass amount of the hydraulic fluid that can be displaced and circulated between the upper and lower liquid chambers 13 and 14 via 16 and an outer cylinder 19 that houses the cylinder 12 are configured. Outer cylinder 19
The base cover 19a is attached to the lower end of the
The inside is sealed. The bottom mounting eye 2 on the base cover 19a
0 is provided.

The damping force generation mechanism 16 is a plurality of passages 21 that are spaced apart in the circumferential direction of the piston 15 and penetrated in the vertical direction, and an upper damping valve 22 that is attached to the upper surface of the piston 15 and elastically blocks the passage 21. At least one of the plurality of passages 21 formed on the upper surface of the piston 15 and closed by the damping valve 22 is connected to the upper liquid chamber 13
To the slit 23 for communicating with the lower surface of the piston 15, and the passage 21 communicated with the upper liquid chamber 13 with the slit 23 out of the plurality of passages 21 installed in the concave portion 25 while blocking the other. The lower damping valve 26 that releases the passage 21 of the lower damping chamber 26 to the lower liquid chamber 14 and the spring bearing 17b fixed to the lower end of the support shaft portion 17a that is continuously attached to the piston rod 17 apply reaction force to the lower damping valve 26. The spring 27 is pressed against the recess 25. And, in the extension stroke and the pressure stroke,
As the piston 15 moves up and down in the cylinder 12, the damping fluid is generated by displacing and circulating the working fluid between the upper and lower fluid chambers 13 and 14.

The damping force varying mechanism 18 is provided in a piston rod 17 and a support shaft portion 17a connected to the piston rod 17, and a bypass passage 30 that communicates between the upper and lower liquid chambers 13 and 14 separately from the damping force generating mechanism 16.
And two lateral holes 31 which are provided on the outer circumference of the piston rod 17 so as to face each other and allow the bypass passage 30 to communicate with the upper liquid chamber 13.
And a tubular adjuster 32 that is rotatably mounted in the bypass passage 30 and closes the lateral hole 31. Bypass passage
The lower end of 30 is open to the lower liquid chamber 14. The adjuster 32 is provided with a plurality of adjustment openings 32a having different diameters in the circumferential direction. Of the plurality of adjustment openings 32a, the two openings 32a facing each other are set to have the same diameter. Then, as the adjuster 32 rotates, the two opposing adjustment openings 32a of the respective adjustment openings 32a coincide with the two lateral holes 31 of the piston rod 17 and the opening of the bypass passage 30 to the upper liquid chamber 13 is formed. The area is adjusted. This adjuster
32 is connected to a control rod 35 provided in the piston rod 17 so as to penetrate in the axial direction thereof.

The outer cover 11 is formed in a bottomed cylindrical body opening downward. Specifically, a bottomed cylindrical outer cylinder 40 and this outer cylinder
A dust plate 41 that is inserted into the outer cylinder 40 to form a component mounting space in the outer cylinder 40, and a skirt portion 42 that extends downward from the dust plate 41 and covers the outer cylinder 19 of the shock absorber portion 10. There is. An upper mounting eye 40c is provided on the upper side of the outer cylinder 40.

An actuator 45 is mounted in the space defined by the dust plate 41 in the outer cover 11. The output shaft 45a of the actuator 45 is connected to the upper end of the control rod 35 so that the adjuster 32 is variably controlled by the actuator 45. Piston rod
17 is fixed to a dust plate 41 provided on the outer cover 11, and the upper end of the piston rod 17 is attached to the base plate 50 of the actuator 45. This allows
As the outer cover 11 moves relative to the shock absorber portion 10 in association with the extension stroke and the pressure stroke of the hydraulic shock absorber, the piston
15 is moved up and down in the cylinder 12.

As shown in FIG. 2, the actuator 45 mainly includes a casing 46, an output shaft 45a, a rotor 47, and a stator 48. The casing 46 includes a base plate 50, which is a non-magnetic material, and a cylindrical cover 51 having a bottom.

The rotor 47 is a lower plate attached to the upper side surface of the base plate 50.
A rotary cylinder 58 rotatably supported by bearings 55 and 56 attached to the upper plate 53 and the upper plate 54, respectively.
The rotating body 59 is integrally fixed to the rotating body 59, and the magnet 60 is integrally attached to the outer periphery of the rotating body 59. The output shaft 45a is fixed to the rotary cylinder 58 by a pin 61 so as to rotate integrally. The output shaft 45a is provided so as to protrude below the base plate 50, and a substantially elliptical fitting hole 62 (see FIG. 3) is formed at the lower end thereof.

The stator 48 faces the magnet 66 with the coil 66 mounted on the bobbin case 65 fixed to the base plate 50 side via the lower plate 53 via the mount base 66a, and the magnet 60 mounted in the center of the coil 66. And a core portion 67 that is attached. Reference numeral 68 in the figure denotes a harness that supplies a current from a power source (not shown).

The actuator 45 is mounted on the upper end of the outer cover 11 as shown in FIG. Upper surface 45b of actuator 45 and upper end of outer cylinder 40 of outer cover 11 Inner surface 4
A wave washer 70 is interposed between 0a and 0a. As a result, the actuator 45 is elastically supported by the outer cylinder 40 and absorbs rattling in the thrust direction (axial center direction). The outer cylinder 40 is provided with a harness drawing hole 40b, and the harness 68 is drawn out from the drawing hole 40b. Reference numeral 68a indicates a grommet that seals the extraction hole 40b, and this grommet 68a is a plate 69a.
And is supported and fixed by a screw 69b for fixing the plate 69a.

As shown in FIG. 3, a star washer 71 having a large number of claws 71a is fixed to the lower side of the actuator 45 by screws 72. The outer diameter of the star washer 71 including the claw portion 71a is larger than the inner diameter of the outer cylinder 40. Then, when the actuator 45 is inserted into the outer cylinder 40, the claw portions 71a of the star washer 71 interfere with the inner surface of the outer cylinder 40 to support the actuator 45, and the thrust direction and the radial direction (rotational direction). It is designed to absorb rattling.

The upper end of the control rod 35 is the actuator.
The output shaft 45a of 45 is formed in an approximately elliptical shape similar to the fitting hole 62 of the output shaft 45a, and is allowed to move in the axial direction of each other.
The rotation direction is fixed.

In the damping force variable type hydraulic shock absorber configured as described above,
During the normal compression stroke, the shock absorber portion 10 and the outer cover 11 are
Relatively expand and contract, and the piston 15 moves up and down in the cylinder 12 via the piston rod 17. And piston 15
Due to the vertical movement in the cylinder 12, the hydraulic fluid in the cylinder 12 is displaced and distributed between the upper and lower liquid chambers 13 and 14 via the damping force generating mechanism 16, and at that time, a damping force is generated.

Then, when adjusting the damping force, a control current is supplied from the power supply side to the actuator 45 via the harness 68.
The supplied current is applied to each coil 66 via the mount base 66a to generate a magnetic field. And the rotor 47
The magnet 60 is attracted or repelled by the magnetic field and rotates by a predetermined angle. Along with this, the output shaft 45a rotates, and the adjuster of the damping force varying mechanism 18 via the control rod 35.
Rotate 32. Due to the rotation of the adjuster 32, one of the adjustment openings 32a and the lateral hole 31 of the piston rod 17 are aligned with each other, and the upper and lower liquid chambers 13, 1 are connected via the bypass passage 30.
The amount of bypass liquid that is replaced and distributed between the four is adjusted. This controls the magnitude of the deceleration force.

With the above configuration, the wave washer 70 interposed between the outer cover 11 and the upper side surface of the actuator 45 does not deteriorate due to heat, vibrations, etc., and reliably supports the actuator 45 to ensure the thrust direction. Absorbs rattling.

Further, the star washer 71 provided on the lower surface of the actuator 45 interferes with the inner peripheral surface of the outer cover 11 to support the actuator 45, which facilitates attachment of the actuator 45 and rattles the actuator 45 in the thrust and radial directions. Absorbs.

Further, when the actuator 45 is attached to the outer cover 11, since the actuator 45 is inserted into the outer cover 11 while being supported by the star washer 71, there is no rattling in the thrust direction and the radial direction, and the outer cover 11
When assembling the shock absorber portion 10 and the shock absorber portion 10, it becomes easy to rotate the outer cover 11 to align the adjustment opening 32a of the adjuster 32 and the lateral hole 31 of the piston rod 17 via the control rod 35, and to assemble the assembly. Workability is improved.

<Effect of Device> As described above, according to the variable damping force type hydraulic shock absorber of the present invention, the damping force variable mechanism provided in the piston rod for variably adjusting the damping force and the outer cover are provided. An actuator that is provided and is connected to the damping force variable mechanism to variably control the damping force variable mechanism, a wave washer interposed between the inner side surface of the outer cover and the upper side surface of the actuator, and the outer side provided on the lower side surface of the actuator. Since the star washer that interferes with the inner peripheral surface of the cover and supports its own weight is provided, the wave washer interposed between the outer cover and the upper side surface of the actuator does not deteriorate due to heat and vibration, etc. It becomes possible to support and absorb rattling in the thrust direction.

In addition, the star washer provided on the lower side of the actuator interferes with the inner surface of the outer cover to support the actuator, facilitating the attachment of the actuator and absorbing the rattling in the thrust and radial directions of the actuator to reduce the damping force. It becomes easy to connect the variable mechanism and the actuator, and the assembling workability is improved.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a variable damping force type hydraulic shock absorber of the present invention, FIG. 2 is a side sectional view showing an actuator of the variable damping force type hydraulic shock absorber of FIG. 1, and FIG. 2 is a rear view of the actuator shown in FIG. 2, and FIG. 4 is a side sectional view showing a conventional damping force variable hydraulic shock absorber. 17 ... Piston rod, 18 ... Damping force variable mechanism, 45 ... Actuator, 70 ... Wave washer, 71 ... Star washer.

Claims (1)

[Scope of utility model registration request] 1. A damping force variable mechanism provided in a piston rod for variably adjusting a damping force; and an actuator provided in an outer cover and connected to the damping force variable mechanism for variably controlling the damping force variable mechanism. , A wave washer interposed between the inner surface of the outer cover and the upper surface of the actuator for axially urging the actuator, and a claw portion provided on the lower surface of the actuator on the inner peripheral surface of the outer cover. A variable damping force type hydraulic shock absorber, comprising a star washer that interferes with and stops the actuator.