JPS6199733A - Structure of coupling rod to securing member - Google Patents

Abstract

PURPOSE:To enable the spring constant and the damping factor of a bush to be varied from the outside, by a method wherein a valve body disposed in a hole in a rod is actuated, and a passage part, through which fluid chambers are intercommunicated, is varied. CONSTITUTION:When a valve body 80 is rotated in a 60 deg. are clockwise, a first fluid chamber 46 is communicated with a second fluid chamber 48. In which case, a spring constant is brought to an intermediate state, and since the bore of a passage part 26b is small, a high damping force is generated as a result of fluid being fluidized. When the valve body 80 is further rotated in a 60 deg. arc clockwise, the first fluid chamber 46 is communicated with the second fluid chamber 48. In which case, the spring constant is brought to a soft state, and since the bore of a passage part 26a is large, fluidization of fluid results in the generation of a low damping force. This enables artificial or automatic variation of the spring constant and the damping factor of a bush.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a structure for coupling a rod to a fixed member, and more particularly, to a structure for coupling a rod such as a piston rod or a strut rod to a vehicle body or other fixed member. Regarding.

(Prior art) For example, when attaching a shock absorber piston rod to a vehicle body, a structure is generally adopted in which a rubber bush is interposed to prevent vibrations from being transmitted from the shock absorber to the vehicle body. In the insulation structure disclosed in Japanese Utility Model Application Publication No. 58-78837, the spring constant of the bushing is uniquely determined and cannot be changed after the shape etc. are determined and assembled to the vehicle body. 1st by bush and board
A second fluid chamber is defined by a diaphragm and a plate placed on the opposite side of the bushing with a plate in between, and both fluid chambers are communicated through an orifice to fill one fluid chamber with fluid. are doing. According to this, vibrations in the high frequency range transmitted from the shock absorber can be reduced by the bushing, and vibrations in the low frequency range can be reduced by the damping force generated when the fluid passes through the orifice.

In the cushion assembly disclosed in Japanese Utility Model Application Publication No. 57-1139112, a pair of cushions having a sealed space on both sides are arranged with a fixing member in between, and the two closed spaces are communicated with each other by an orifice, so that a peripheral sealed space is formed. Fluid is sealed inside to improve harshness characteristics.

(Problems to be Solved by the Invention) In the structures disclosed in the above-mentioned publications, it is not possible to manually or automatically change the spring constant or damping coefficient of the bushing depending on driving conditions or preference.

The present invention provides a structure for connecting a rod to a fixed member, which allows the spring constant and damping coefficient of the bushing to be changed from the outside.

(Means for Solving the Problems) The coupling structure according to the present invention includes a rod having first and second passages connected at a distance from a hole into which a valve body is inserted and a wire hole; a bushing having a first fluid chamber communicating with the rod and a second fluid chamber communicating with the second passage, the bushing being disposed radially outward of the rod, and a member for fixing the bushing; It has a third passage that allows communication between the first passage and the second passage, and includes a valve body disposed in the hole of the rod, and an actuator that operates the valve body.

(Example) Examples of the present invention will be described below with reference to the drawings.

Coupling structure 10 includes a rod 12 and a bush 14, as shown in FIG.

In the illustrated example, the rod 12 is a piston rod of a shock absorber, and the coupling structure 10 couples the piston rod to a vehicle body 16, which is a fixed member.

In the example shown in FIG. 9, the rod 12 has a hole 18 for inserting a valve body, and a first passage 20 and a second passage 22 connected to the wire hole 18 at intervals.

Disposed on the outside of the rod 12 is an inner bay 24 made of a rigid material such as iron. This is Bush 1
This is for convenience when forming the bushing 14 and assembling the bushing 14 to the rod 12, but the internal information 24 can also be made unnecessary.

The hole 18 in the rod 12 is inserted into the rod 1 as shown in FIG.
It extends from the end face of 2 in the axial direction. In the example shown in FIG. 2, the first passage 20 consists of a pair of passage parts 26a each extending from a portion above the hole 18 toward the outer peripheral surface, and a pair of passage parts 26b having a smaller diameter than the passage parts 26a. In the example shown in FIG.
It consists of a pair of passage portions 28a each extending from a lower portion toward the outer peripheral surface, and a pair of passage portions 28b having the same diameter as the passage portions 28a. The first passage 20 and the second passage 22 have the same phase relationship in plan view.

The inner cylinder 24 includes a hole 25 through which the rod 12 passes, an annular groove 30 provided in a portion of the rod 12 facing the first passage 20, and a plurality of (second In addition, it has an annular groove 32 provided in a portion of the rod 12 facing the second passage 2z, and a plurality of holes 31 (six in the figure) extending from the annular groove 32 in the radial direction to the outer circumferential surface. In FIG. 3, there are six holes 33.

Pass the rod 12 through the hole 25 of the inner cylinder 4, abut the ring 34 fixed to the rod against the shoulder of the hole 25, and attach a washer 36 and a bracket 38 to the part of the rod that protrudes from the inner bay 24.
The rod 12 is connected to the inner cylinder 24 by applying the same and screwing the nut 40 together. The rod 12 and the inner cylinder 24 are
0 ring 42 placed above the upper annular $llll30
, an O-ring 44 disposed below the lower annular t+132
It is said to be airtight.

The bushing 14 has a first fluid chamber 46 communicating with the first passage 20 and a second fluid chamber 48 communicating with the second passage 22.
In the illustrated example, each bushing 14 has a ring-shaped portion 5 of rubber and is disposed radially outwardly surrounding the rod 12.
0. It consists of a second part 51 and a third part 52.

The first portion 50 of the bushing is the inner surface of the bore 3 of the inner tube 24.
At the end of the inner cylinder 24 that is above 1, there is an outer cylinder 54 on the outer surface.
are vulcanized and bonded to the upper ends of the cylindrical portions 56, respectively. The second part 51 of the bushing has a second inner cylinder 6 on its inner surface.
0, and the outer surface thereof is vulcanized and bonded to the second outer cylinder 62, respectively. This second portion 51 has a second inner cylinder 6 located below the hole 31 of the inner cylinder 24 to which the O-ring 64 is attached.
0 and is fixed to the inner tube 24, and the second outer tube 62 is fitted into the cylindrical portion 56 of the outer tube 54. As a result, the first part 50 and the second part 51 of the bushing are
A fluid chamber 46 is defined.

In the illustrated example, the second inner cylinder 60 extends downward beyond the hole 33, and the O member 66 whose lower end abuts the member 66 is fitted with the O ring 68 and fitted into the inner cylinder 24. , inside information 2
It is fixed by caulking 4. The diameter of the second inner cylinder 60 is increased below the portion facing the hole 33, and a gap 70 is formed between the second inner cylinder 60 and the inner cylinder 24. This gap 70 communicates with the second passage 22 via the hole 33 and the annular groove 32 on the one hand, and with the second fluid chamber 48 via a plurality of notches 71 provided in the second inner cylinder 60 on the other hand. It goes through. The reason why the second inner cylinder 60 is configured in this way is to facilitate the positioning of the second inner cylinder 60, but the second inner cylinder 60 can also be made to have a length that does not cover the hole 33. .

The third portion 52 of the bushing is vulcanized to the retainer 72 at the upper end and to the member 66 at the inner periphery of the lower end. A plurality of ports 74 (only one is shown in the figure) having serrations are press-fitted into the retainer 72. These ports 74 are passed through the flange portion 57 of the outer cylinder 54 and the vehicle body 16, and nuts are inserted into the ports 74. 76, the third portion 52 of the bushing is fixed to the vehicle body 16. As a result, a second fluid chamber 4B is defined between the second portion 51 and the third portion 52 of the bush.

The valve body 80 consists of an IT valve stem body part 82 and a second valve body part 84 . The wSl valve body part 82 is formed into a flat-bottomed cylindrical shape, and has a hole 88 extending diametrically from an axial hole 86 toward the outer circumferential surface and spaced downward from the chain hole 88 .

The hole 90 extends diametrically from the placed portion toward the outer circumferential surface. When the first valve body portion 82 is placed in a predetermined position on the rod 12, the hole 88 is located in the first passage 20 of the rod 12.
In addition, the holes 90 respectively face the second passages 22 .

As a result, the holes 86, 88, and 9 of the first valve body portion 82
0, a third passage that can communicate the passage 20 of fJIJl and the second passage 22 is formed.

The second valve body portion 84 is connected to the first valve body portion 82 through serrations 92, and an upper portion 93 is formed flat.

When the holes 88,90 of the valve body 80 are in the positions shown in FIGS. 2 and 883, the first passage 20 and the second passage 22 are blocked. When the valve body 80 is rotated 60” clockwise,
The hole 88 communicates with the pair of passage portions 26b, and the hole 90 communicates with the pair of passage portions 28b. Further, when the valve body 80 rotates 60' clockwise, the hole 88 is inserted into the pair of passage portions 26a.
The hole 90 communicates with the pair of passage portions 28a.

A spacer 94 and an O-ring 96 are attached to the lower end of the first valve body part 82 to which the fJS2 valve body part 84 is coupled.
The valve body portion 92 is rotatably arranged in the hole 18 of the rod 12 . The rod 12 and the valve body 80 are further connected to each other by an O-ring 98 disposed above the first passage 20 and an O-ring 99 disposed between the first passage 20 and the second passage 22. It is made airtight by an O-ring 102 that abuts the upper end of the section 82 and is held by a collar 100.

Actuator 104 is coupled to rod 12 via bracket 38. The actuator 104 consists of a known electric motor and a reduction gear, and its output shaft 106
The flat portion 93 of the valve body 80 is inserted into the slit provided in the valve body 80 , and the valve body 80 is rotated by the actuator 104 .

(Operation of the embodiment) A fluid, that is, oil or other liquid, air or other gas, or a mixture of liquid and gas is sealed in the first and second fluid chambers.

When the vehicle is running, the actuator 104 is activated by manual operation by the driver or by operation of a controller that receives signals from a speed sensor, an acceleration sensor, a steering wheel rotation angular velocity sensor, and other sensors. to rotate the valve body 80.

When the valve body 80 is in the position shown in FIG. 2, the first passage 20 and the second passage 22 are blocked, so the fluid does not flow, and the spring constant of the bushing 14 is in a stiff state, causing no damping. No force is generated.

When the valve body 80 rotates 60 degrees clockwise, the hole 8B of the valve body
is in the pair of passage portions 26b, and the hole 90 is in the pair of passage portions 26b.
As a result, the first fluid chamber 46 and the second
It communicates with the fluid chamber 48 of. At this time, since the spring constant is in an intermediate state and the diameter of the passage portion 26b is small, a large damping force is generated by the fluid flow.

When the valve body 80 further rotates 60 degrees clockwise, the hole 88
is in the pair of passage portions 28a, and the hole 90 is in the pair of passage portions 28a.
As a result, the first fluid chamber 46 and the second
It communicates with the fluid chamber 48 of. At this time, the spring constant is soft and the diameter of the passage portion 28a is large, so
A small damping force is generated by the fluid flow.

(Another Example) In the above example, the rod is a piston rod, but the present invention can be practiced even if the rod is a strut rod that restricts the back and forth movement of the suspension arm. In this case, the shape of the bushing is formed to match the strut rod.

(Effects of the Invention) According to the present invention, if the piston rod of the shock absorber is connected to the vehicle body, the spring constant and damping coefficient of the bushing can be changed manually or automatically, so that the spring constant and damping coefficient of the bushing can be changed manually or automatically. By changing these, it is possible to improve riding comfort, steering stability, running stability, etc., and reduce vibration noise.

By coupling the strut rod to the vehicle body according to the present invention, harshness and flutter characteristics can be improved, and ride comfort can be improved.

Furthermore, since the rod is provided with two passages and the valve body is disposed within the rod, the overall structure can be made compact, reducing weight and cost.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the coupling structure according to the present invention, and FIG.
3 is a sectional view taken along line 2-2 in the figure, and FIG. 3 is a sectional view taken along line 3-3 in FIG. lO: coupling structure, 12: rod, 14 nib, shoe, 16: vehicle body, 18: hole, 20: first passage, 22: i2 passage, 46: first fluid chamber, 48: second fluid chamber , 8
0: Valve body, 104:7 Cutuator. Agent Patent Attorney Nobuyuki Matsunaga Figure 1 Figure 2 Figure 36

Claims (1)

[Claims] A rod having a hole into which a valve body is inserted, first and second passages connected to the hole at a distance, and a first fluid chamber communicating with the first passage and communicating with the second passage. a bushing having a second fluid chamber and disposed radially outward of the rod; a member fixing the bushing; and a member fixing the bushing;
has a third passage that can communicate with the passage and the second passage,
A structure for coupling a rod to a fixed member, including a valve body disposed in the hole of the rod, and an actuator that operates the valve body.