JP2010077978A - Liquid-sealed torque rod - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid-sealed torque rod capable of attaining the high damping effect and reduction in the vibration transmission ratio, without enlarging a part in the axial direction. <P>SOLUTION: This liquid-sealed torque rod has a sub-liquid chamber arranged in a plate-like connecting member for connecting an engine side bush and a vehicle body side bush and having two wall surfaces along an outer peripheral shape of the connecting member in an upper surface view, an orifice passage having a bending shape, and a communicating part formed in the sub-liquid chamber, including the center of the two wall surfaces and connected with the orifice passage. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid-sealed torque rod.

Conventionally, the technique described in Patent Document 1 is known as a liquid-sealed torque rod. In this publication, a main liquid chamber is formed in the engine-side bush, a secondary liquid chamber is formed in the rod body, and these are connected by an orifice passage, thereby obtaining an effect of suppressing engine vibration.
JP 2005-291448 A

  However, in the technique described in Patent Document 1, the main liquid chamber and the sub liquid chamber are linearly connected, and in order to reduce the vibration transmissibility by a high damping effect, the size of the parts in the axial direction is increased. There was a problem.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a liquid-sealed torque rod capable of reducing vibration transmissibility by a high damping effect without causing an increase in the size of components in the axial direction. And

  In order to achieve the above object, in the present invention, a secondary liquid chamber is disposed on a plate-like connection member that connects the engine-side bush and the vehicle-body-side bush, and has two wall surfaces along the outer peripheral shape of the connection member when viewed from above. And an orifice passage having a bent shape, and a communication portion formed in the secondary liquid chamber and including a position equidistant between the two wall surfaces between the two wall surfaces to which the orifice passage is connected.

  Therefore, in the liquid-sealed torque rod according to the present invention, since the path length of the orifice passage is increased, a high damping effect and a reduced vibration transmissibility can be achieved without causing an increase in the size of the parts in the axial direction.

  The best mode for realizing the liquid-sealed torque rod of the present invention will be described below based on the embodiments shown in the drawings.

  FIG. 1 is a schematic view of a vehicle to which the liquid-sealed torque rod of Example 1 is applied. Side members SM extending in the vehicle front-rear direction are provided on both sides of the vehicle. The side member SM is joined to the body. A cross member CM extending in the vehicle width direction is provided in the vicinity of the pillar joint portion.

  The engine ENG is supported on the side member SM on the lower side via an engine mount EM, and is connected to a cross member CM (hereinafter referred to as the vehicle body side) on the upper vehicle interior side via a liquid-sealed torque rod TR. Supported. The engine ENG shown in FIG. 1 is placed horizontally in the engine room (the crankshaft is in the vehicle width direction). As indicated by the arrow in FIG. 1, the torque rod TR functions as a reaction force receiver during torque output of the engine ENG, and avoids vibration and the like being transmitted to the cross member CM and the body side.

  The engine type may be either an in-line cylinder or a V-type cylinder, and is not particularly limited. Further, the torque rod TR is provided between the cross member CM and the engine ENG. However, the torque rod TR is not limited to the cross member CM, and may be a portion that can ensure a predetermined strength on the vehicle body side.

  FIG. 2 is a top view of the torque rod TR, and FIG. 3 is a cross-sectional view taken along the line AA of the torque rod. The torque rod TR has a connecting member 3 formed by superposing an upper plate 3a and a lower plate 3b having substantially the same shape in the thickness direction. The outer peripheral shape of the connection member 3 in a top view is an oval that connects the vehicle body side arc and the engine side arc with a straight line corresponding to a tangent line between the outer periphery of the vehicle body side bush 1 and the engine side bush 2 described later. ing.

  Oval refers to a shape close to an ellipse with at least one line-symmetric part. In the first embodiment, a line (corresponding to the line AA) connecting the support portion center of the vehicle body side bush 1 and the support portion center of the engine side bush 2 in the top view is a symmetric line, and the connecting member 3 The outer shape is a target shape across this symmetry line.

  A first upper cylindrical portion 3a1 on the vehicle body side is formed on the right end side in FIG. 2 of the upper plate 3a, and a second upper cylindrical portion 3a2 on the engine side is formed on the left end side in FIG. Between the first upper cylindrical portion 3a1 and the second upper cylindrical portion 3a2 and closer to the second upper cylindrical portion 3a2 (a position closer to the engine-side bush 2 than the vehicle body-side bush 1), the outer peripheral shape is viewed from above. A substantially liquid trapezoid trapezoidal opening edge 3a3 is formed. In the auxiliary liquid chamber opening edge 3a3, the side 3a31 serving as the leg of the isosceles trapezoid is formed along the straight portion of the connecting member 3 (oval).

  A first lower cylindrical portion 3b1 on the vehicle body side is formed on the right end side in FIG. 2 of the lower plate 3b, and a second lower cylindrical portion 3b2 on the engine side is formed on the left end side in FIG. ing. The first upper cylindrical portion 3a1 and the first lower cylindrical portion 3b1 form a cylindrical portion, and the vehicle body side bush 1 is attached in the cylindrical portion. Similarly, a cylindrical portion is formed by the second upper cylindrical portion 3a2 and the second lower cylindrical portion 3b2, and the engine-side bush 2 is attached in the cylindrical portion.

  On the mating surface side with the lower plate 3b of the upper plate 3a, an upper rubber layer 30a formed by vulcanization molding by pouring rubber into a vulcanization mold is formed. When the upper rubber layer 30a is formed, a rubber film is simultaneously formed along the sub liquid chamber opening edge 3a3 on the surface opposite to the mating surface. Thereby, a diaphragm 31a having a substantially isosceles trapezoidal shape in a top view is formed, and the inside of the diaphragm 31a forms a part of the auxiliary liquid chamber 5. The diaphragm 31a has two wall surfaces 31a1 along the side 3a31.

  On the mating surface side of the lower plate 3b with the upper plate 3a, a lower rubber layer 30b formed by vulcanization molding by pouring rubber into a vulcanization mold is formed. When the lower rubber layer 30 b is formed, a concave portion 31 b that becomes a part of the auxiliary liquid chamber 5 and an orifice passage groove 32 b that meanders in a concave shape that becomes a part of the orifice passage 6 are formed.

  The upper plate 3a and the lower plate 3b are overlapped, and the auxiliary liquid chamber 5 is formed by the inside of the diaphragm 31a and the recess 31b. At the same time, the orifice passage 6 is formed by the orifice passage groove 32b and the upper rubber layer 30a. In other words, the wall surface of the orifice passage 6 is formed of rubber of the upper rubber layer 30a and rubber of the lower rubber layer 30b, that is, an elastic body.

  The vehicle body side bush 1 is a rubber member having a substantially circular outer shape, and has an engagement portion 1b that engages with the vehicle body side at a substantially center. In the vehicle body side direction of the engaging portion 1b, a straight portion 1a is formed to adjust the characteristics of the vehicle body side bush 1. A substantially crescent-shaped main liquid chamber 4 is formed in the engine side direction of the engaging portion 1b in a top view.

  The main liquid chamber 4 has a main liquid chamber side communication portion 4a connected to the orifice passage 6 on the lower side in FIG. Thus, the orifice passage 6 is secured longer by disposing the main liquid chamber side communication portion 4a below the line AA.

  The orifice passage 6 extends along the line AA from the main liquid chamber side communication portion 4a in a top view, then bends substantially at a right angle, crosses the line AA, and bends near the outer periphery of the connection member 3. Invert and cross line AA again. Similarly, it is bent and reversed near the outer periphery of the connecting member 3, is bent at a substantially right angle along the line AA, and is connected to the auxiliary liquid chamber side communication portion 5 a provided in the auxiliary liquid chamber 5 along the line AA. Connecting.

  In other words, the secondary liquid chamber 5 has a secondary liquid chamber side communication portion 5a connected to the orifice passage 6, and the secondary liquid chamber side communication portion 5a is formed of two wall surfaces formed along the two sides 3a31. It is formed at a position including the center (coincidence with the line AA), that is, a position that is between the two wall surfaces and is equidistant from the two wall surfaces in a top view.

  In the first embodiment, the center of the secondary liquid chamber side communication portion 5a is formed so as to substantially coincide with the AA line, but the AA line is included in the opening of the secondary liquid chamber side communication portion 5a. As long as it is within the range, the centers do not necessarily have to coincide.

  Further, the secondary liquid chamber side communication portion 5a is formed on the lower surface side in a side view. That is, the sub liquid chamber has a diaphragm 31a formed so as to protrude to the upper plate 3a side (one surface side) in a side view, and the sub liquid chamber side communication portion 5a has a lower side opposite to the diaphragm 31a in a side view. It is formed on the side plate 3b side (the other side). The main liquid chamber 4, the orifice passage 6 and the sub liquid chamber 5 are filled with an incompressible fluid and sealed so as to have a substantially atmospheric pressure when no load is applied.

  The operation based on each of the above configurations will be described. For example, when a displacement load is input from the engine ENG side and the volume of the main liquid chamber 4 changes due to the relative displacement between the engaging portion 1 b and the connecting member 3, the incompressible fluid in the main liquid chamber 4 flows into the orifice passage 6. Is supplied to the auxiliary liquid chamber 5. Since the auxiliary liquid chamber 5 has the diaphragm 31a, the diaphragm 31a is swollen by the supplied incompressible fluid and absorbs the increased volume. When the displacement load from the engine ENG side decreases, the diaphragm 31a contracts, and the incompressible fluid is returned from the secondary liquid chamber 5 to the main liquid chamber 4 through the orifice passage 6. The vibration-proofing effect is exhibited by the flow of such an incompressible fluid, that is, the flow action such as the resonance action of the fluid flowing through the orifice passage 6.

  Here, the main role of the orifice passage 6 is to secure the flow resistance, and the secondary liquid chamber 5 is to secure the function of absorbing the flow rate change. In other words, in the role of the secondary liquid chamber 5, unlike the role of the orifice passage 6, it is preferable that the flow resistance at the time of absorbing the volume change is small in that the accuracy in designing the system can be improved.

  From the above, in order to ensure the flow resistance of the orifice passage 6, the orifice passage 6 has a bent shape. Thereby, the path length of the orifice passage 6 becomes longer, and the flow resistance applied to the fluid increases. As a result, the damping force increases as intended. In addition, since the flow resistance also increases at the bent portion, the damping force can be increased more effectively. Therefore, the damping effect can be increased without increasing the axial length of the torque rod TR.

  In addition, since the orifice passage 6 is formed of an elastic body such as rubber, fluid pressure loss in the orifice passage 6 can be suppressed, and generation of abnormal noise can be further suppressed.

  Here, when the flow resistance in the orifice passage 6 is increased and the flow resistance in the sub liquid chamber 5 is large, the flow of the fluid is excessively deteriorated as a whole, and a desired damping force reduction function can be obtained. Can not. In addition, abnormal noise such as cavitation occurs due to fluid pressure loss.

  Therefore, the flow of fluid between the main liquid chamber 4 and the sub liquid chamber 5 is maintained by reducing the flow resistance when the fluid flows out and inflow from the orifice passage 6 to the sub liquid chamber 5. In other words, the position of the secondary liquid chamber side communication portion 5a is examined so that the role of the secondary liquid chamber 5 can be fully exhibited, and the flow resistance in the secondary liquid chamber 5 is suppressed.

  Specifically, by arranging the secondary liquid chamber side communication portion 5a in the vicinity of the line AA in a top view, the fluid flows in a laminar flow when the fluid enters and exits between the orifice passage 6 and the secondary liquid chamber 5. A certain state can be maintained, and the flow resistance between the orifice passage 6 and the auxiliary liquid chamber 5 is suppressed. If the position of the sub liquid chamber side communication portion 5a is arranged at the corner of the sub liquid chamber 5, the fluid flow is turbulent in the sub liquid chamber side communication portion 5a, resulting in an increase in flow resistance. Because it ends up.

  Further, the secondary liquid chamber side communication portion 5a is disposed at a position opposite to the diaphragm 31a with respect to the center position in the height direction of the secondary liquid chamber 5 in a side view. In other words, the sub liquid chamber has a diaphragm 31a formed so as to protrude to the upper plate 3a side (one surface side) in a side view, and the sub liquid chamber side communication portion 5a is on the opposite side of the diaphragm 31a in a side view. It is formed on the lower plate 3b side (the other surface side).

  In the vicinity of the diaphragm 31a of the sub liquid chamber 5, a turbulent flow is generated in the fluid flow by the vibration of the diaphragm 31a. Therefore, if the sub liquid chamber side communication portion 5a is provided in the vicinity of the diaphragm 31a, the flow resistance against the entry and exit of the fluid is increased, so that the damping force cannot be obtained and the function as the damping force generating device cannot be obtained. Furthermore, abnormal noise such as cavitation occurs due to fluid pressure loss. Therefore, by providing the auxiliary liquid chamber side communication portion 5a at a position away from the diaphragm 31a with little turbulent flow, fluid pressure loss can be suppressed while securing a damping force.

As described above, in the liquid-sealed torque rod of the first embodiment, the following effects can be obtained.
(1) Connection between the engine side bush 2, the vehicle body side bush 1, the plate-like connection member 3 connecting the engine side bush 2 and the vehicle body side bush 1, and the main liquid chamber 4 disposed in the vehicle body side bush 1. The auxiliary liquid chamber 5 having two wall surfaces 31a1 arranged along the outer peripheral shape of the connecting member 3 in a top view and the main liquid chamber 4 and the auxiliary liquid chamber 5 connected to each other are arranged in the connecting member 3. In addition, the orifice passage 6 having a bent shape and the sub-liquid chamber 5 are formed so as to include a position between the two wall surfaces 31a1 and at the same distance from the two wall surfaces when viewed from above. And a secondary liquid chamber side communication portion 5a.

  Therefore, the damping force can be effectively increased by increasing the flow resistance in the orifice passage 6. Further, the flow resistance between the orifice passage 6 and the sub liquid chamber 5 can be suppressed by the arrangement of the sub liquid chamber side communication portion 5a, and the function of the sub liquid chamber 5 can be secured. Further, by forming the auxiliary liquid chamber 5 along the outer peripheral shape of the connecting member 3, it is possible to effectively use the space, and it is possible to improve the performance of the auxiliary liquid chamber 5 without causing an increase in size. From the above, it is possible to achieve a high damping effect and a reduced vibration transmissibility without causing an increase in the size of the parts in the axial direction.

  (2) The orifice passage 6 is formed of rubber (elastic body). Therefore, fluid pressure loss in the orifice passage 6 can be suppressed, and abnormal noise can be further suppressed.

  (3) The auxiliary liquid chamber 5 has a diaphragm 31a formed so as to protrude to the upper plate 3a side (one surface side) in the side view of the connecting member 3, and the auxiliary liquid chamber side communication portion 5a It is formed on the lower plate 3b side (the other surface side) opposite to the diaphragm 31a in a side view.

  Therefore, the sub liquid chamber side communication part 5a can be provided at a position away from the diaphragm 31a with little turbulent flow, and a fluid pressure loss can be suppressed while securing a damping force.

  As described above, the description has been made based on the first embodiment. However, the design is not limited to the above configuration, and the design can be changed as appropriate within the scope of the present invention. For example, in the first embodiment, the main liquid chamber 4 is arranged in the vehicle body side bush 1, but the main liquid chamber may be arranged in the engine side bush 2. Although it is conceivable to arrange the main liquid chambers on both sides, the effect cost obtained by providing two is small, and it is preferable to provide only one of them from the viewpoint of cost.

  In the first embodiment, the shape of the connection member 3 in the top view is an oval. However, the shape is not limited to this. For example, the connection member 3 may have a plate shape having parallel sides, or may have a curved portion. Absent.

  Moreover, in Example 1, although the orifice channel | path 6 was formed by the recessed part 31b formed in the upper side rubber layer 30a and the lower side rubber layer 30b, you may arrange | position the hose etc. which consist of elastic materials separately.

  Further, in Example 1, the concave portion is formed only in the lower rubber layer 30b, but the concave portion is also formed in the upper rubber layer 30a so as to bend in the thickness direction in addition to the bending in the plane direction. It may be.

1 is a schematic view of a vehicle provided with a torque rod of Example 1. FIG. 1 is a top view of a torque rod of Example 1. FIG. It is AA sectional drawing of the torque rod of Example 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Car body side bush 2 Engine side bush 3 Connection member 4 Main liquid chamber 5 Sub liquid chamber 5a Sub liquid chamber side communication part (communication part)
6 Orifice passage
31a1 Wall 31a Diaphragm

Claims (3)

The engine side bush,
Body side bush,
A plate-like connecting member for connecting the engine side bush and the vehicle body side bush;
A main liquid chamber disposed on one of the engine side bush or the vehicle body side bush;
A secondary liquid chamber disposed on the connection member and having two wall surfaces along the outer peripheral shape of the connection member in a top view;
An orifice passage disposed in the connecting member, connecting the main liquid chamber and the sub liquid chamber, and having a bent shape;
A communication portion formed in the sub-liquid chamber, including a position between the two wall surfaces and equidistant from the two wall surfaces in a top view, to which the orifice passage is connected;
A liquid-sealed torque rod characterized by comprising: The liquid-filled torque rod according to claim 1,
The liquid-sealed torque rod, wherein the orifice passage is formed of an elastic body. The liquid-sealed torque rod according to claim 1 or 2,
The sub liquid chamber has a diaphragm formed to protrude to one surface side in a side view of the connection member,
The communication portion is formed on the other surface side opposite to the diaphragm in a side view of the connection member.

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