JPH038818Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a seal structure for a fluid-filled bush.

(Prior Art) In a vehicle suspension, a fluid-filled bushing is provided at the end of a suspension arm, and such fluid-filled bushings include left and right halves provided between an inner cylinder and an outer cylinder. A rubber cylinder consisting of a large diameter part that connects the inner cylinder and the outer cylinder near both ends of the rubber cylinder, a small diameter part provided near the middle part of the rubber cylinder, and a full-circumference recess formed between the outer periphery of the small diameter part and the outer cylinder. abutting portions of the left and right halves of the outer periphery of the small diameter portion and over the entire periphery within the entire circumference recess;
A partition wall is provided to define the circumferential recessed portion into two fluid chambers, and a communication passage is provided to communicate the two fluid chambers, so that hydraulic oil in one fluid chamber flows out to the other fluid chamber through the communication passage. There are some that try to obtain damping force.

(Problem to be solved by the invention) However, in such a fluid-filled bushing, when the hydraulic oil in one fluid chamber flows out to the other fluid chamber, the pressure in the fluid chamber increases, and this causes A gap may occur between the outer periphery of the small diameter portion and the partition wall, and therefore it has been desired to seal more reliably between the outer periphery of the small diameter portion and the partition wall.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a rubber cylinder consisting of left and right halves provided between the inner cylinder and the outer cylinder, and the inner cylinder and the outer cylinder are connected near both ends of the rubber cylinder. It consists of a large diameter part that joins together, a small diameter part that is formed near the middle part in the length direction of the rubber tube and brings the left and right halves into contact, and a full-circumference recess that is formed between the outer periphery of the small diameter part and the outer cylinder. , a partition wall that abuts in the entire circumference recess near the abutting portions of the left and right halves of the outer periphery of the small diameter portion and over the entire circumference, and defines the entire circumference recess into two fluid chambers in the cylinder axis direction; and a fluid-filled bushing having a communication path for communicating both fluid chambers, characterized in that a seal ring having a harder hardness than the rubber cylinder is provided at the contact portion of the small diameter portion of the left and right halves. do.

(Function) Even if the pressure in the fluid chamber increases and the small diameter part of the rubber cylinder is reduced toward the inner cylinder side, and a gap is created between the small diameter part outer periphery and the partition wall, the seal ring will keep the small diameter part outer periphery and the partition wall apart. Moreover, since this seal ring has high hardness, it does not contract even when the pressure in the fluid chamber increases, and thus can provide a more reliable seal.

(Example) Examples will be described in detail below based on the accompanying drawings.

FIG. 1 is a side cross-sectional view of a fluid-filled bushing installed in the mounting portion of the radius rod on the vehicle body side. A small diameter portion 2 is formed at the front end of the radius rod 1, and a threaded portion 3 is provided at the tip. A mounting pipe 6 is fixed to the vehicle body frame 5, and a large opening 7 is formed at the middle upper part of the pipe 6, and small openings 8, 8 are formed at the lower left and right sides of the pipe 6, and the upper opening 7 faces the part of the frame 5. An opening 9 is also formed. A long protection pipe 11 is further fitted and fixed in the mounting pipe 6, and this pipe 11 is also formed with openings 12, 13, 13 similar to those described above.

The main body of the fluid-filled bush 21 includes a support cylinder 22,
It consists of an inner cylinder 31 and an outer cylinder 35, a rubber cylinder 41 that connects the inner and outer cylinders 31 and 35, and an annular plate-shaped partition wall 51.

The support tube 22 is fitted onto the small diameter portion 2 of the radius slot 1, and has an outer flange 23 at one end.
A threaded portion 24 is formed on the outer periphery of the other end.

The inner cylinder 31, the outer cylinder 35, and the rubber cylinder 41 are all composed of divided bodies in the cylinder axis direction, and the cylinder halves 32, 3
The inner cylinder 31 made up of the two cylinder halves is fitted onto the support cylinder 22, and the outer cylinder 35 made up of the cylinder halves 36, 36 is fitted into the protection pipe 11.

The rubber cylinder 41 is composed of left and right halves 42, 42, and these halves 42, 42 are in contact with each other via a seal ring 80, which will be described later. Also, rubber tube 41
Large diameter parts 41a, 41a are formed at both outer ends of the outer cylinder 35, and the small diameter cylinder part 3 of the outer cylinder 35
7 and the inner cylinder 31 are bonded together by baking. Furthermore, rubber tube 4
Small diameter portions 41b, 41b are formed in the intermediate portion in the length direction of 1, that is, in the vicinity of the abutting portion of each half body 42, 42,
A full-circumference recess 49 is formed between the outer periphery of the small diameter portions 41b and 41b and the outer cylinder 35. Moreover, the large diameter portion 41a,
41a extends to the stepped portion of the small diameter cylindrical portion 37 of the outer cylinder half 36 to provide a rubber portion 45, and extends to the tip of the small diameter cylindrical portion 37 to provide a rubber portion 46.
Furthermore, stopper protrusions 47 are provided on the inner surfaces of the large diameter portions 44, 44 facing the circumferential recess 49.

The partition wall 51 has a thick annular plate shape, and its inner periphery abuts the entire circumference near the contact portion of the half bodies 42, 42 on the outer periphery of the small diameter portion 41b, 41b of each half body 42, 42, and There are cylindrical parts 5 on the outer periphery on both sides in the axial direction of the cylinder.
9 and 59, the inner periphery of this cylindrical portion 59 fits onto the small step cylindrical portion 37 of the outer cylinder half 36, and the outer periphery of the partition wall 51 fits into the protection pipe 11.
Due to this partition wall 51, two fluid chambers are formed in the circumferential recess 49 on the outer periphery of the intermediate portion of the rubber cylinder 41 in the cylinder axis direction.
Defined by O ₁ and O ₂ .

A seal ring 80 interposed between the abutting portions of the halves 42 and 42 is made of a material harder than the rubber tube 41, and its inner circumference fits into the inner tube 31 and its outer circumference abuts the partition wall 51.

Further, a flat surface 52 is formed on a part of the outer periphery of the partition wall 51, a circular recess 53 is formed in this flat surface 52, and through holes 54, 54 passing through this circular recess 53 in the cylinder axis direction are formed. do. In addition, there are second
As shown in the figure, small recesses 55, 55 are formed, and passages 56, 56 with a step in the middle are formed near the inner circumference of the recesses, and both passages 56, 56 are blocked by the step. Screw-on drain pot 5
7 and 57 are housed in the small recesses 55 and 55.

A valve 61 is rotatably fitted into the circular recess 53 of the partition wall 51. The valve 61 has a base formed into a rod portion 62 with a small diameter, and this rod portion 6
A seal ring 63 is fitted around the outer periphery of the rod portion 62, and a shaft hole 64 is formed at the end of the rod portion 62. Further, the tip portion is formed into a cylindrical portion 65 that fits into the circular recess 53,
As shown in FIG.
67 is opened. Here, one set of valve holes 66 has the same diameter as the through hole 54, and the other set of valve holes 67, whose center angle differs by 60 degrees, has a smaller diameter.

Also, the rod portion 62 and the circular recess 53 of the valve 61
A holder collar 71 is interposed between them. color 71
A seal ring 72 is fitted on the outer periphery of the collar 71, and an outer flange 73 that abuts the flat surface 52 is provided at the end of the collar 71.

Furthermore, a drive control device 75 for the valve 61 is attached to the flat surface 52. The drive control device 75 is made up of a mounting base 76 that houses a valve switching mechanism using a motor or the like inside, and a cylindrical case 77 that is fixed to the mounting base 76. From the end of the base 76, the valve switching mechanism rotates the rotation angle three times in 120° increments. A drive shaft 78 that can be switched in stages is provided protrudingly. The drive shaft 78 is fitted into the shaft hole 64 at the end of the valve 61, and the mounting base 76 is fixedly connected to the flat surface 52 at the front and rear with bolts 79, 79.

The drive control device 75 is operated by a control unit provided in the vehicle interior, and when the larger valve hole 66 is aligned with the through hole 54 of the partition wall 51 as shown in FIG. The hydraulic oil in the bush 21 is not restricted by the valve hole 66, and therefore the compliance characteristics against the load in the cylinder axis direction are soft.

When the smaller valve hole 67 is aligned with the through hole 54, the hydraulic oil is squeezed by the valve hole 67, so
The orifice effect generates a damping force and the compliance characteristics become hard.

Further, when the through hole 54 is closed with the valve 61, the communication path is blocked by the valve 61, and therefore both fluid chambers are closed.
Since the communication between O ₁ and O ₂ is cut off, the compliance characteristics become the stiffest.

In the above, when one of the fluid chambers O ₁ and O ₂ contracts and the hydraulic oil therein flows out to the other fluid chamber through the through hole 54 etc., the pressure in the fluid chamber increases,
As a result, the hydraulic oil tends to enter between the outer periphery of the small diameter portions 41b and 41b and the partition wall 51. However, this intrusion of the hydraulic oil is prevented by the seal ring 80, and since the seal ring 80 has high hardness, it can maintain sealing performance without shrinking even when the pressure of the hydraulic oil increases.

4 and 5 show another embodiment of the present invention,
In the case shown in FIG. 4, the small diameter portion 41 of the rubber tube 41
b An annular protrusion 85a is formed on the outer periphery, and an annular lip 85b is formed in the case of FIG. In addition, the sealing performance of the fluid-filled bushing is further improved.

(Effects of the invention) As described above, according to the invention, even if the pressure in the fluid chamber increases and a gap is created between the outer periphery of the small diameter part and the partition wall, the seal ring can seal the gap between the outer periphery of the small diameter part and the partition wall. Also, since this seal ring has high hardness, it does not contract even when the pressure in the fluid chamber increases, and thus can provide a more reliable seal.

[Brief explanation of the drawing]

Figure 1 is a side sectional view of the fluid-filled bushing installed in the mounting part of the radius rod on the vehicle body side, Figures 2 and 3 are
The figures are cross-sectional views taken along the lines in FIG. 1 and -, and FIGS. 4 and 5 show other embodiments. In the drawing, 21 is a fluid-filled bush, 31 is an inner cylinder, 35 is an outer cylinder, 41 is a rubber cylinder, 41a is a large diameter part, 41b is a small diameter part, 42 is a half body, 49 is a circumferential recessed part, 51 54 is a partition wall, 54 is a communication path, 80 is a seal ring, 85a is an annular projection, 85b is an annular lip, and O ₁ and O ₂ are fluid chambers.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A rubber cylinder consisting of left and right halves provided between an inner cylinder and an outer cylinder, a large diameter portion that connects the inner cylinder and the outer cylinder near both ends of the rubber cylinder, and a rubber cylinder a small diameter part formed near the middle part in the longitudinal direction of the body and which brings the left and right halves into contact; and a full circumference recess formed between the outer periphery of the small diameter part and the outer cylinder, and the small diameter part is located within the full circumference recess. A partition wall is provided that abuts the left and right halves of the outer periphery near the abutting portions and around the entire periphery, and defines the entire periphery recess into two fluid chambers in the direction of the cylinder axis, and a connection that connects both fluid chambers. A seal structure for a fluid-filled bushing having a passage, characterized in that a seal ring having a harder hardness than the rubber cylinder is interposed between the contact portions of the small diameter portions of the left and right halves. . (2) A sealing structure for a fluid-filled bush according to claim 1, wherein an annular protrusion is formed at a portion of the outer periphery of the small diameter portion of the rubber cylinder that contacts the partition wall. (3) A sealing structure for a fluid-filled bushing according to claim 1, wherein an annular lip is formed at a portion of the outer periphery of the small diameter portion of the rubber cylinder that contacts the partition wall.