JP2000002285A - Liquid sealing vibration isolation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve vibration isolation function of a liquid sealing vibration isolation device, and inexpensively improve its durability. SOLUTION: A rubber elastic body 30 which integrally connects an inner cylindrical metal fitting 10 and an intermediate metal fitting having a ring part 21 and a connection part, has a pair of side walls 31 for connecting a pair of ring parts to the inner cylindrical metal fitting, and arm 31 extending across the side walls in an axial direction for connecting between the connection part and the inner cylindrical metal fitting, and a seal part 38 adhered to an outer periphery of the intermediate metal fitting. The rubber elastic body 30 also has a recession surrounded by the paired side walls and the arm, and opened to both sides in a main vibration input direction between both the rings. A projection rubber part 37 projected outward from an axial end of the cylindrical part is integrally arranged on an extended portion from the arm, on the outer side surfaces of the paired side walls. The thicker the side wall is, the higher its rigidity is for performing effective liquid column resonance action. It is also possible to inexpensively improve durability of the side walls.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid filled type vibration damping device used for an engine mount of a vehicle or the like.

[0002]

2. Description of the Related Art Hitherto, as this type of liquid-filled type vibration damping device, for example, those shown in FIGS. 7 to 9 are known.
The liquid filled type vibration damping device includes an inner cylindrical fitting 1 having a stopper member 2 facing the main vibration input direction attached to an outer peripheral surface,
It is arranged coaxially at a distance outside the inner cylindrical fitting 1 and has a pair of ring portions 3a at both ends in the axial direction.
a, a cylindrical intermediate fitting 3 having a pair of connecting portions 3b connecting the two ring portions 3a at both radial positions substantially orthogonal to the main vibration input direction, a pair of ring portions 3a and an inner cylinder. A pair of side wall portions 4a connecting the metal fittings 1 and a pair of side wall portions 4;
and an arm portion 4b extending in the axial direction between the inner metal member 1 and the connecting portion 3b and the inner cylindrical metal member 1, and a seal portion 4c fixed to the outer periphery of the intermediate metal member 3 are provided. A substantially cylindrical rubber elastic body 4 having concave portions 4d and 4e surrounded by the outer ring 4b and opened in the vertical direction of the main vibration input direction between the two ring portions 3a, and a seal portion 4c outside the intermediate metal fitting 3 A main liquid chamber 5 which is coaxially arranged and has a liquid-tightly closed opening of the recesses 4d and 4e and filled with liquid between the recesses 4d and 4e;
a and a sub-liquid chamber 5b, and an orifice passage 5c for connecting the main liquid chamber 5a and the sub-liquid chamber 5b with the connecting portion 3b. And a fitting (not shown) that is press-fitted and fixed.

In this liquid filled type vibration damping device, for example, an inner cylinder fitting 1 is connected to a support member (not shown) on the vehicle body side, and a mounting fitting is connected to a support member (not shown) on the engine side. The stopper member 2 is arranged in the vertical direction, which is the main vibration input direction, and the main liquid chamber 5a and the sub liquid chamber 5b are arranged in the vertical position.
When vibration occurs between the inner cylinder 1 and the mounting bracket, the vibration is attenuated by the elastic action of the rubber elastic body 4 and the liquid column resonance action of the liquid flowing through the orifice passage 5c.

[0004]

In the above-described liquid-filled type vibration damping device, when vibration in the main vibration input direction is applied, the main liquid chamber 5a and the sub liquid chamber 5b alternately contract and expand. The liquid in the liquid chamber flows through the orifice passage 5c. In this case, since the side wall 4a surrounding the main liquid chamber 5a is formed of a rubber material, the side wall 4a receives the pressure fluctuation inside the main liquid chamber 5a. May swell outward in the axial direction or be pulled inward. Therefore, the amount of the liquid flowing through the orifice passage 5c is smaller than the pressure fluctuation of the main liquid chamber 5a, and there is a problem that the vibration damping force due to the liquid column resonance in the orifice passage 5c is reduced.

[0005] Further, when the side wall portion 4a expands outward in the axial direction, the rubber elastic body 4 easily comes into contact with other members (not shown) provided around the liquid-filled type vibration damping device. There is a possibility that the durability of the enclosed type vibration damping device may be reduced. On the other hand, a method in which substantially plate-shaped side stoppers are attached in the direction perpendicular to the axis at positions near both ends of the outer peripheral surface of the inner cylindrical metal fitting 1 has been performed. The vibration device becomes expensive.

An object of the present invention is to provide a liquid-filled type vibration damping device which can prevent the deterioration of the vibration damping function and can improve the durability at a low cost. I do.

[0007]

In order to achieve the above object, the structural features of the invention described in claim 1 are: an inner cylinder fitting connected to one of a vehicle body and an engine; Coaxially spaced apart outside the inner tube fitting,
A cylindrical shape having a pair of ring portions at both ends in the axial direction, and a pair of connecting portions connecting the two ring portions at both radial positions substantially orthogonal to the main vibration input direction between the pair of ring portions. An intermediate bracket, a pair of side walls connecting between the pair of ring portions and the inner cylinder, an arm extending in the axial direction between the pair of side walls and coupling between the coupling and the inner cylinder, A cylindrical rubber elastic body having a seal portion fixed to the outer periphery of the metal fitting and having a concave portion surrounded by a pair of side wall portions and the arm portion and opened on both sides in the main vibration input direction between the two ring portions; A main liquid chamber and a sub liquid chamber filled with a liquid are formed between the fixing part and the concave part by liquid-tightly closing the opening of the concave part and fixed to the outside of the metal fitting via a seal part, and between the connecting part. A cylindrical portion forming an orifice passage communicating the main liquid chamber and the sub liquid chamber, and provided outside the cylindrical portion A mounting bracket having a mounting portion connected to the other of the vehicle body and the engine, wherein the axial direction of the cylindrical portion is set at a position extended from the arms on the outer surfaces of the pair of side walls. That is, a protruding rubber portion protruding outward from the end is provided integrally.

According to the first aspect of the present invention, the thickness of the side wall is increased and the rigidity of the side wall is increased by providing the protruding rubber portion on the outer side of the side wall which is the extension of the arm. Can be Therefore, the deformation of the side wall due to the vibration input is suppressed, and the liquid flows in the orifice passage according to the vibration input. As a result, according to the first aspect of the invention, it is possible to prevent the vibration-proof function of the liquid-filled vibration-proof device from lowering.

Further, since the protruding rubber portion protrudes outward from the axial end of the cylindrical portion, it acts as a stopper for peripheral members, so that the durability of the side wall portion can be reduced without providing a separate member such as a side stopper. Enhanced. As a result, the durability of the liquid-filled type vibration damping device can be improved at low cost.

A second feature of the invention according to the second aspect is that, in the liquid filled type vibration damping device according to the first aspect, the protruding rubber portion is provided at a position near the cylindrical portion. It is in. In the second aspect of the present invention, the rigidity of the side wall portion is increased by providing the protruding rubber portion near the cylindrical portion having a thinner side wall portion than the inner cylindrical metal fitting side. Therefore, the deformation of the side wall portion at the time of vibration input can be suppressed more reliably. As a result, according to the second aspect of the invention, in addition to the effect of the first aspect, the vibration-proof function of the liquid-filled vibration-proof device can be reliably enhanced.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIGS. 1, 2 and 3 show a liquid-filled type vibration damping device according to the embodiment in a front view and an axial sectional view. FIG. 3 is a diagram and a cross-sectional view in a direction perpendicular to the axis (both excluding a mounting bracket).

The liquid filled type vibration damping device includes an inner cylinder fitting 10,
A stopper member 11 fixed to the inner cylinder fitting 10 and having a tip projecting in the main vibration input direction (vertical direction in the drawing);
A pair of ring portions 21 arranged coaxially and spaced outside the
Substantially cylindrical intermediate metal fitting 20 having two connecting portions 22 and
A substantially cylindrical rubber elastic body 30 which integrally connects the intermediate metal fitting 20 and the inner cylindrical metal fitting 10 and has a seal portion 38 and a pair of concave portions 33 and 34;
The main liquid chamber 41 and the sub liquid chamber 42 which are fixed through the opening and which communicate with each other through the orifice passage 43 between the concave parts 33 and 34.
And a mounting bracket 50 having a cylindrical portion 51 that is press-fitted to the outside of the outer cylinder fitting 40 as main components.

The inner tube fitting 10 is a pipe-shaped fitting.
A stopper member 11 is fitted and fixed to the outer peripheral surface of the inner cylinder fitting 10. The stopper member 11 is formed of a resin, and as shown in FIGS. 2 and 3, a cylindrical portion 11 a fitted on the outer peripheral surface of the inner cylindrical member 10, and upward from the outer peripheral surface of the cylindrical portion 11 a in the main vibration input direction. And a rod-shaped first stopper portion 11b projecting into the main liquid chamber 41, and projecting from an outer peripheral surface of the cylindrical portion 11a toward a side opposite to the first stopper portion 11b, and
A second stopper portion 11c extending in the axial direction.

The intermediate metal fitting 20 includes a pair of ring portions 21 coaxially located at both ends in the axial direction, and two window portions 23 bridged between the two ring portions 21 and arranged in the circumferential direction together with the ring portions 21. It is composed of two substantially long plate-shaped connecting portions 22 that are partitioned. The two connecting portions 22 are provided at both side positions in the radial direction substantially orthogonal to the main vibration input direction.

The rubber elastic body 30 has a pair of side walls 31 that connect the ring portion 21 and the inner cylindrical member 10 over substantially the entire circumference in the axial direction, and a pair of connection portions extending in the axial direction between the pair of side walls 31. The connection between the portion 22 and the inner cylindrical fitting 10 (including the stopper member 11), and the second stopper portion 11c
Arm 32 extending to the vicinity of the window 23 on the side thereof,
And a seal portion 38 fixed to the outer periphery of the seal member. As a result, as shown in FIG.
2, a concave portion 33 opened in the upper window portion 23 in the figure and a concave portion 34 opened in the lower window portion 23 by being divided into approximately two parts are provided. Inside the recess 33, a first stopper 11b protrudes upward in the main vibration input direction. Also, the inner cylindrical fitting 10 of the rubber elastic body 30 is used.
A hollow portion 35 penetrating along the axial direction is provided in a portion between the hollow portion 35 and the concave portion 34.
A part of the rubber elastic body 30 is thinned at a portion between the diaphragm 36 and the diaphragm 36 to form a partition wall with the auxiliary liquid chamber 42.

As shown in FIGS. 1, 2 and 4, the axially outer surface of the side wall portion 31 is provided with a distal end at the axially extended position of the arm portion 32 and at a position near the outer cylinder fitting 40. Protruding rubber portion 37 whose surface protrudes from both peripheral ends of cylindrical portion 51
Are provided integrally on both sides in the axial direction. The rubber elastic body 30 is vulcanized and formed by performing vulcanization molding in a state in which the inner cylinder fitting 10 and the intermediate metal fitting 20 are set in a molding die (not shown). It is integrally formed as a product (not shown).

The outer tube fitting 40 is press-fitted and fixed to the outer periphery of the rubber vulcanized molded product via a seal portion 38. As a result, the openings of the concave portions 33 and 34 of the rubber elastic body 30 are closed in a liquid-tight manner, and the main portions communicating with the concave portions 33 and 34 via the orifice passage 43 which is a gap outside the connecting portion 22. A liquid chamber 41 and a sub liquid chamber 42 are formed. Water is sealed in the main liquid chamber 41, the sub liquid chamber 42, and the orifice passage 43. In this case, the method of sealing the liquid is as follows.
The rubber vulcanized molded product in which the rubber elastic body 30 is integrated with the outer cylinder fitting 40 is immersed, and in this state, the rubber vulcanized molded product is pressed into the outer cylinder fitting 40 and fitted. Here, water is used as the liquid to be sealed, but the present invention is not limited to this. For example, other incompressible fluids such as alkylene glycol and silicone oil can be sealed.

As shown in FIGS. 5 and 6, the mounting member 50 includes a cylindrical portion 51 and a mounting portion 52 having a deformed shape attached to the outer peripheral surface of the cylindrical portion 51 by welding. The mounting portion 52 is formed by punching and bending a metal plate, and includes a base portion 52a and a pair of vertical portions 52b provided vertically on both side edges thereof. The base 52a is a deformed flat plate symmetrical in the width direction and includes a substantially trapezoidal intermediate portion 52a1 and rectangular portions 52a2, 52a3 extending on the same plane from upper and lower bottoms thereof. The distal end side of the narrower rectangular portion 52a3 is a protruding piece 52a4 with both sides cut out in a substantially rectangular shape. Also, three mounting holes 52a5 are formed in the base 52a for inserting mounting bolts (not shown). Vertical part 52
b is a curved plate erected along both side edges of the base 52a, and has a substantially triangular shape in a side view in which the edge 52b1 on the side of the rectangular portion 52a3 stands substantially vertically. The edge 52b1 is formed to be concave in an arc shape. The mounting bracket 50 makes the protruding piece 52a4 of the base 52a of the mounting part 52 abut on the cylindrical part 51, and also has both edges 5 of the vertical part 52b.
2b1 is assembled by welding and fixing to the tubular portion 51. The outer cylinder fitting 40 integrated with the rubber vulcanization molded product is press-fitted and fixed to the tubular portion 51 of the mounting fitting 50 to complete the liquid filled type vibration damping device of the present embodiment.

In the liquid filled vibration isolator constructed as described above, for example, the inner cylinder fitting 10 is connected to a support member (not shown) on the vehicle body side, and is attached to a support member (not shown) on the engine side. The mounting portion 52 of the metal fitting 50 is connected by a mounting bolt, and is disposed such that the main liquid chamber 41 and the sub liquid chamber 42 are located in the vertical direction which is the main vibration input direction of the engine. When vibration occurs between the inner cylinder fitting 10 and the mounting fitting 50, the vibration is attenuated by the elastic action of the rubber elastic body 30 and the liquid column resonance action of the liquid flowing through the orifice passage 43. When excessive vibration occurs between the inner cylindrical member 10 and the mounting member 50, the distal end surface of the stopper member 11 contacts the outer cylindrical member 40 via the inner peripheral surface of the opposed cylindrical portion 51 or the diaphragm 36. By doing so, the displacement is suppressed within a predetermined range.

In this case, by providing the protruding rubber portion 37 on the surface of the side wall portion 31 corresponding to the axially extending position of the arm portion 32, the side wall portion 3 of the axially extending portion of the arm portion 32 is provided.
1 is increased in thickness to increase its rigidity. By increasing the rigidity of the side wall 31, deformation of the side wall 31 in the axial direction due to vibration input is suppressed. Thereby, the liquid flows in the orifice passage 43 according to the vibration input, and the vibration can be efficiently attenuated. For this reason, it is possible to prevent a decrease in the vibration-proof function of the liquid-filled vibration-proof device. In addition, since the protruding rubber portion 37 is provided in the vicinity of the relatively thin outer tube fitting 20 of the side wall portion 31,
Deformation of the side wall 31 at the time of vibration input can be suppressed efficiently.

Further, since the protruding rubber portion 37 protrudes outward from the axial end of the cylindrical portion 51, the protruding rubber portion 37 acts as a stopper for a peripheral member (not shown). The durability of the side wall portion 31 is improved without providing a separate member. Therefore, the durability of the liquid-filled type vibration damping device can be improved at low cost.

The protruding rubber portion 37 is entirely or partially disposed at an axially extending position of the arm portion 32 so that the side wall portion 3 is formed.
The arrangement is not limited to the vicinity of the outer tube fitting 20 but may be changed as appropriate as long as the rigidity is improved. Further, in the present embodiment, the outer cylinder fitting 40 is used, but instead of this, the outer cylinder fitting 40 is omitted, and the tubular portion 51 of the mounting bracket 50 is directly press-fitted and fixed to the outer periphery of the rubber vulcanization molded product. You may do so. Note that the specific structure of the liquid-filled type vibration damping device shown in the above embodiment is not limited to this.

[Brief description of the drawings]

FIG. 1 is a front view (excluding a mounting bracket) schematically showing a liquid filled type vibration damping device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II shown in FIG.

FIG. 3 is a sectional view taken along the line III-III shown in FIG. 2;

FIG. 4 is a sectional view taken along the line IV-IV shown in FIG.

FIG. 5 is a plan view schematically showing the liquid filled type vibration damping device.

FIG. 6 is a front view schematically showing the liquid filled type vibration damping device.

FIG. 7 is a front view (excluding a mounting bracket) schematically showing a liquid-filled type vibration damping device according to a conventional example.

8 is a sectional view taken along the line VIII-VIII shown in FIG.

FIG. 9 is a sectional view taken along the line IX-IX shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Inner cylinder fitting, 11 ... Stopper member, 20 ... Intermediate fitting, 21 ... Ring part, 22 ... Connection part, 23 ... Window part, 30
... rubber elastic body, 31 ... side wall part, 32 ... arm part, 33, 34
... recess, 35 ... cavity, 36 ... diaphragm, 37 ... protruding rubber part, 38 ... seal part, 40 ... outer cylinder fitting, 41 ... main liquid chamber, 42 ... auxiliary liquid chamber, 43 ... orifice passage, 50 ... mounting fitting , 51 ... cylindrical part, 52 ... mounting part, 52a ... base part,
52a1... Middle part, 52a2, 52a3.
2a4: projecting piece, 52a5: mounting hole, 52b: vertical part,
52b1 ... edge.

Claims (2)

[Claims] 1. An inner cylindrical member connected to one of a vehicle body and an engine, and a pair of ring portions disposed coaxially at an outer side of the inner cylindrical member and spaced apart from each other in the axial direction. A tubular intermediate fitting having a pair of connecting portions that connect the two ring portions at both radial positions substantially orthogonal to the main vibration input direction between the pair of ring portions; and the pair of rings. A pair of side walls connecting the portion and the inner cylinder, an arm extending axially between the pair of side walls and connecting the connection and the inner cylinder, and an outer periphery of the intermediate metal. A cylindrical rubber elastic body provided with a seal portion to be fixed and having a concave portion surrounded by the pair of side wall portions and the arm portion and opened on both sides in the main vibration input direction between the two ring portions; Is fixed to the outside through the seal portion,
The opening of the concave portion is liquid-tightly closed to form a main liquid chamber and a sub liquid chamber filled with liquid between the concave portion and the main liquid chamber and the sub liquid chamber between the connecting portion and the main liquid chamber. Liquid-filled vibration isolator comprising: a tubular portion forming an orifice passage for communicating with a vehicle; and a mounting bracket provided outside the cylindrical portion and connected to the other of the vehicle body and the engine. In the liquid filling, a protruding rubber portion that protrudes outward from an axial end of the cylindrical portion is integrally provided at an extended position of the outer surface of the pair of side wall portions from the arm portion. Type anti-vibration device. 2. The liquid filled vibration damping device according to claim 1, wherein the protruding rubber portion is provided at a position near the cylindrical portion.