JP3838280B2 - Liquid-filled engine mount - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid-filled engine mount disposed between a vehicle engine and a vehicle body.
[0002]
[Prior art]
Generally, an engine mount for a vehicle has a high damping characteristic for reducing vibration in a low frequency range (around 15 Hz) and a low dynamic spring characteristic for reducing vibration and noise in a high frequency range (100 Hz or more). In order to satisfy this requirement, various liquid-sealed engine mounts have been proposed and put into practical use.
[0003]
This liquid-filled engine mount is basically provided with a rubber elastic body on one side of a partition member as disclosed in, for example, Japanese Patent Publication No. 4-17291, and a working chamber is defined in the rubber elastic body. In addition, an equilibrium chamber surrounded by a flexible member such as a flexible thin film is formed on the other side of the partition member, and a predetermined incompressible fluid is sealed in the working chamber and the equilibrium chamber. The working chamber and the equilibrium chamber communicate with each other through an orifice, and a movable plate supported by the partition member is provided so as to be movable by a predetermined distance by the pressure applied to the fluid in the working chamber. When low frequency vibration is input, the fluid flows between the working chamber and the equilibrium chamber through the orifice, and the loss factor of the entire mount is increased by the action of resonance, flow resistance, etc. of the fluid. Improve the attenuation characteristics against. Further, when high frequency vibration is input, the volume of the working chamber is changed by the movement of the movable plate, so that the dynamic spring constant is lowered.
[0004]
[Problems to be solved by the invention]
However, the conventional liquid-filled engine mount requires a flexible member and a movable plate for forming an equilibrium chamber in addition to a member for attaching to the engine and the vehicle body, a rubber elastic body, and a partition member. However, since the number of parts is large, there is a problem that the cost increases accordingly. In particular, in the above-mentioned publication, the partition member is composed of two members in order to form an orifice composed of an annular space, so that the number of parts is increased and the cost is further increased.
[0005]
The present invention has been made in view of such a point, and an object of the present invention is to effectively utilize the compressibility of air to achieve a high damping characteristic in a low frequency range and a low dynamic spring characteristic in a high frequency range. It is an object of the present invention to provide a liquid-sealed engine mount capable of reducing the number of parts as much as possible while reducing the cost.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 is characterized in that the first and second members respectively attached to the engine and the vehicle body, and the rubber elasticity bonded to both members so as to form a sealed space between the two members. And a partition member that partitions the sealed space into a lower chamber and an upper chamber. And the annular groove which forms annular space between the peripheral part of the said partition member and the 1st or 2nd member which this peripheral part contact | abuts, and the 1st which communicates between the said annular space and the said lower chamber And a second communication hole that communicates between the annular space and the upper chamber, and a concave portion directed upward is formed in the central portion of the partition member so that the lower chamber serves as the main liquid chamber and the concave portion. And a secondary liquid chamber. The main liquid chamber, the sub liquid chamber, the annular space, and the upper chamber are filled with liquid while leaving air in the upper portions of the sub liquid chamber and the upper chamber, respectively, and the concave portion includes the sub liquid chamber and the upper chamber. A small hole is formed to maintain a constant amount of air in the secondary liquid chamber, the upper end position of the small hole is made to coincide with the liquid level of the liquid sealed in the secondary liquid chamber, and It is set as the structure located below the liquid level of the liquid enclosed with the chamber .
[0007]
Thereby, at the time of low frequency vibration input, the liquid flows between the lower chamber and the upper chamber through the annular space on the peripheral edge of the partition member and the first and second communication holes, and the resonance and flow resistance of the liquid. As a result, the loss coefficient of the entire mount is increased, so that the damping characteristic against low frequency vibration is enhanced. In addition, when high frequency vibration is input, the volume of the sub-liquid chamber and hence the liquid in the lower chamber is changed due to the compressibility of the air in the upper portion of the sub-liquid chamber, so that the dynamic spring constant is lowered. In addition, since a flexible member and a movable plate are not required as in the prior art, and the partition member is also a single member, the number of parts can be reduced, and the cost can be reduced accordingly.
[0008]
Further, since the above-mentioned recess to form a small hole in order to keep the air volume of the auxiliary liquid chamber communicates the auxiliary fluid chamber and the upper chamber constant air volume of the sub liquid chamber is kept constant In addition, it is possible to always ensure the fluctuation of the volume of the lower chamber due to the compressibility of air and the low dynamic spring characteristics with high frequency vibration.
[0009]
According to a second aspect of the present invention, in the liquid-filled engine mount according to the first aspect, a throttle portion is provided at a desired portion of the main liquid chamber of the sub liquid chamber. The frequency at which the low dynamic spring characteristic is exhibited can be arbitrarily changed by adjusting the aperture of the throttle portion.
[0010]
According to a third aspect of the present invention, in the liquid-filled engine mount according to the first aspect, of the first and second members, the member with which the peripheral edge of the partition member abuts is a bottomed cylindrical member and the The cylindrical member is connected to the opening edge of the bottom cylindrical member by caulking, and the peripheral portion of the partition member is sandwiched between the caulking portions. As a result, the partition member can be easily and reliably incorporated.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0012]
FIG. 1 shows a liquid-filled engine mount A according to a first embodiment of the present invention. The engine mount A includes a first member 1 attached to the engine, a second member 2 attached to the vehicle body, and the first member. A rubber elastic body 4 vulcanized and bonded to both members so as to form a sealed space 3 between the first and second members 1 and 2, and a partition member 7 that partitions the sealed space 3 into a lower chamber 5 and an upper chamber 6. And.
[0013]
The first member 1 includes a bottomed cylindrical member 11 having a bottom surface portion 11a located on the upper side and a cylindrical member 12 coupled to a lower opening edge of the bottomed cylindrical member 11 by a caulking 15; The second member 2 includes a substantially circular mounting plate 13 and a mounting bolt 14 that penetrates the central portion of the mounting plate 13 and has a large head portion 14a for vulcanization adhesion. A part of 14 a is arranged in a state of being inserted into the cylindrical member 12. The rubber elastic body 4 is formed in a substantially disk shape, its outer peripheral surface is integrally bonded to the inner peripheral surface of the cylindrical member 12, and the central portion is the head 14 a of the mounting bolt 14 and the mounting plate 13. It is integrally bonded to the upper surface. Here, the rubber elastic body 4 is inclined upward from the center toward the outer side in the radial direction. This corresponds to the fact that the engine mount A receives a compressive load when the engine mount A is used. is there.
[0014]
The partition member 7 is a single member made of synthetic resin or metal, as shown in FIGS. 2 to 4, and the peripheral portion of the partition member 7 is in contact with the first member 1 with which the peripheral portion abuts. An annular groove 22 that forms an annular space 21 is provided between the annular space 21 and the first communication that communicates between the annular space 21 and the lower chamber 5 to a portion that forms the bottom wall 22a of the annular groove 22. A second communication hole 24 that communicates between the annular space 21 and the upper chamber 6 is provided at a portion where the hole 23 constitutes the upper side wall 22 b of the annular groove 22. The two communication holes 23 and 24 are provided at a predetermined distance in the circumferential direction of the annular space 21. The peripheral part of the partition member 7 is such that a part constituting the upper side wall 22b of the annular groove 22 extends radially outward from a part constituting the lower side wall 22c of the annular groove 22, and the first member 1 is clamped by one caulking portion 15. The upper end of the outer periphery of the rubber elastic body 4 extends between the peripheral edge of the partition member 7 and the inner peripheral surface of the cylindrical member 12 to seal that portion.
[0015]
In addition, a concave portion 26 is formed integrally with the central portion of the partition member 7 so that the lower chamber 5 below the partition member 7 includes a main liquid chamber 27 that is an original lower chamber and an auxiliary chamber in the concave portion 26. And a liquid chamber 28. The main liquid chamber 27, the sub liquid chamber 28, the annular space 21, and the upper chamber 6 are filled with liquid such as water or alkylene glycol, leaving air in the upper portions of the sub liquid chamber 28 and the upper chamber 6. . A small hole 29 is formed in the concave portion 26 of the partition member 7 so as to communicate the auxiliary liquid chamber 28 and the upper chamber 6, and the amount of air in the auxiliary liquid chamber 28 is kept constant at least at the position of the small hole 29. In addition, a throttle portion 30 having a predetermined diameter is integrally formed at a portion desired for the main liquid chamber 27 of the sub liquid chamber 28 (an opening of the recess 26). Reference numeral 31 denotes a plug for closing the liquid injection hole 32 provided in the bottom surface portion 11 a of the bottomed cylindrical member 11.
[0016]
Next, the operation of the liquid-sealed engine mount A will be described. At the time of low frequency vibration input, the liquid flows between the lower chamber 5 and the upper chamber 6 in the annular space 21 at the peripheral edge of the partition member 7 and the first and second chambers. Since the loss coefficient of the entire mount increases due to the resonance of the liquid, the flow resistance, and the like by flowing through the second communication holes 23 and 24, the damping characteristic against low frequency vibration is enhanced.
[0017]
On the other hand, when high-frequency vibration is input, the volume of the sub-liquid chamber 28 and thus the liquid in the lower chamber 5 is changed by the compressibility of the air inside the sub-liquid chamber 28 of the lower chamber 5. Becomes lower. At that time, the amount of air in the sub-liquid chamber 28 is kept constant at the height position of the small hole 29 formed in the concave portion 26 of the partition member 7, so that the volume of the lower chamber 5 varies due to the compressibility of air. As a result, it is possible to always ensure low dynamic spring characteristics with high frequency vibration. Further, since the throttle part 30 is provided at a desired portion of the main liquid chamber 27 of the sub liquid chamber 28, the frequency at which the low dynamic spring characteristic is exhibited is arbitrarily changed by adjusting the diameter of the throttle part 30. be able to.
[0018]
As described above, according to the liquid-filled engine mount A, it is possible to effectively suppress engine vibration and noise from the low frequency range to the high frequency range. Moreover, the engine mount A is simply composed of the first and second members 1 and 2, the rubber elastic body 4, and the partition member 7, and does not require a flexible member or a movable plate as in the prior art. Moreover, since the partition member 7 is also a single member, the number of parts can be reduced, and the cost can be reduced accordingly.
[0019]
In addition, in the manufacturing process of the engine mount A, after the rubber elastic body 4 is vulcanized and bonded to the cylindrical member 12 and the second member 2 of the first member 1, a partition member is formed from the upper opening edge of the cylindrical member 12. 7 is inserted into the cylindrical member 12, and the lower opening edge of the bottomed cylindrical member 11 is inserted into the upper opening edge of the cylindrical member 12, and the members 11, 12 are interposed between the partition members 7. By caulking in a state where the outer peripheral portion is clamped, the partition member 7 can be easily and reliably assembled.
[0020]
FIG. 5 shows a liquid-filled engine mount B according to the second embodiment of the present invention. The engine mount B is similar to the engine mount A of the first embodiment, and includes a first member 41 attached to the engine, A second member 42 attached to the vehicle body, a rubber elastic body 44 vulcanized and bonded to both members so as to form a sealed space 43 between the first and second members 41, 42, and the sealed space 43 A partition member 47 that partitions the chamber 45 and the upper chamber 46 is provided.
[0021]
The first member 41 has a bottomed cylindrical shape with the bottom surface portion 41a positioned on the upper side, and the second member 42 consists only of a mounting bolt having a large head portion 42a for vulcanization adhesion. The rubber elastic body 44 is formed in a substantially disc shape, and its outer peripheral surface is integrally bonded to the lower inner peripheral surface of the first member 41, and its central portion is on the head 42 a of the second member 42. Bonded together. Here, the rubber elastic body 44 is inclined upward from the center toward the outer side in the radial direction. This corresponds to the fact that the engine mount B receives a compressive load when the engine mount B is used. is there.
[0022]
The partition member 47 is formed thicker than that of the engine mount A of the first embodiment, and the peripheral portion of the partition member 47 is between the first member 41 with which the peripheral portion abuts. Is provided with an annular groove 52 that forms an annular space 51, and a first communication hole that communicates between the annular space 51 and the lower chamber 45 to a portion constituting the lower side wall 52 c of the annular groove 52. 53 is provided with second communication holes 54 that communicate between the annular space 51 and the upper chamber 46 at portions constituting the upper side wall 52 b of the annular groove 52. The communication holes 53 and 54 are provided at a predetermined distance from each other in the circumferential direction of the annular space 51.
[0023]
In addition, a concave portion 56 directed upward is integrally formed at the central portion of the partition member 47, and the lower chamber 45 below the partition member 47 is composed of a main liquid chamber 57 that is an original lower chamber and a sub chamber in the concave portion 56. And a liquid chamber 58. The main liquid chamber 57, the sub liquid chamber 58, the annular space 51, and the upper chamber 46 are filled with liquid while leaving air in the upper portions of the sub liquid chamber 58 and the upper chamber 46. A small hole 59 that allows the secondary liquid chamber 58 and the upper chamber 46 to communicate with each other is formed in the concave portion 56 of the partition member 47 so that the amount of air in the secondary liquid chamber 58 is kept constant at least at the position of the small hole 59. In addition, a throttle portion 60 having a predetermined diameter is integrally formed at a portion desired for the main liquid chamber 57 of the sub liquid chamber 58.
[0024]
In the engine mount B of the second embodiment, as in the case of the engine mount A of the first embodiment, the liquid is separated between the lower chamber 45 and the upper chamber 46 when low frequency vibration is input. Since the loss coefficient of the entire mount increases due to the liquid resonance and flow resistance due to the fluid flowing through the peripheral annular space 51 and the first and second communication holes 53 and 54, the damping characteristics against low frequency vibrations Becomes higher. Further, when high frequency vibration is input, the volume of the sub liquid chamber 58 and thus the liquid in the lower chamber 45 that is filled changes due to the compressibility of the air in the upper portion of the sub liquid chamber 58 of the lower chamber 45. Becomes lower. In addition, since a flexible member and a movable plate are not required as in the prior art, and the partition member 47 is also a single member, the number of parts can be reduced, and the cost can be reduced accordingly. Have
[0025]
FIG. 6 shows a liquid-filled engine mount C according to the third embodiment of the present invention. In the engine mount C, the rubber elastic body 44 is inclined downward from the center toward the radially outer side in response to receiving a tensile load in the use state. The other configuration of the engine mount C is the same as that of the engine mount B of the second embodiment, and the same members are denoted by the same reference numerals and description thereof is omitted. Needless to say, the functions and effects are the same as those of the engine mount B of the second embodiment.
[0026]
【The invention's effect】
As described above, according to the liquid-filled engine mount of the present invention, a flexible member and a movable plate are not required while ensuring high damping characteristics at low frequency vibration and low dynamic spring characteristics at high frequency vibration. Further, since the partition member is also a single member, the number of parts can be reduced as much as possible, and the cost can be reduced.
[0027]
Further , since the amount of air in the auxiliary liquid chamber can be kept constant, it is possible to always ensure low dynamic spring characteristics with high frequency vibration.
[0028]
In the invention according to claim 2 , by providing a throttle part in a desired portion of the main liquid chamber of the sub liquid chamber, and adjusting the aperture of the throttle part, it is possible to arbitrarily change the frequency at which the low dynamic spring characteristic is exhibited. .
[0029]
Furthermore, in the invention which concerns on Claim 3 , the member which the peripheral part of a partition member contact | abuts is divided | segmented, The assembly of a partition member is carried out easily and reliably by clamping the peripheral part of a partition member to the crimping part of both. It has the effect that it can be done.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a liquid-filled engine mount according to a first embodiment of the present invention.
FIG. 2 is a side view of a partition member.
FIG. 3 is a perspective view of a partition member as viewed obliquely from above.
FIG. 4 is a perspective view of a partition member as viewed obliquely from below.
FIG. 5 is a view corresponding to FIG. 1 showing a second embodiment.
FIG. 6 is a view corresponding to FIG. 1 showing a third embodiment.
[Explanation of symbols]
A, B, C Liquid filled engine mount 1,41 First member 2,42 Second member 3,43 Sealed space 4,44 Rubber elastic body 5,45 Lower chamber 6,46 Upper chamber 7,47 Partition member 11 Existence Bottom cylindrical member 12 Cylindrical member 15 Caulking portion 21, 51 Annular space 22, 52 Annular groove 23, 53 First communicating hole 24, 54 Second communicating hole 26, 56 Recessed portion 27, 57 Main liquid chamber 28, 58 Sub liquid chamber 29,59 Small hole 30,60 Restricted part

Claims (3)

First and second members respectively attached to the engine and the vehicle body;
A rubber elastic body bonded to both members so as to form a sealed space between the two members;
A partition member that partitions the sealed space into a lower chamber and an upper chamber;
An annular groove that forms an annular space between the peripheral portion of the partition member and the first or second member with which the peripheral portion abuts, and a first portion that communicates between the annular space and the lower chamber. A communication hole and a second communication hole communicating between the annular space and the upper chamber are provided, and a concave portion is formed at the center of the partition member so that the lower chamber is the main liquid. Chamber and a secondary liquid chamber in the recess,
Liquid is sealed in the main liquid chamber, the sub liquid chamber, the annular space, and the upper chamber, respectively, leaving air in each upper part of the sub liquid chamber and the upper chamber ,
Furthermore, a small hole is formed in the concave portion in order to keep the amount of air in the sub liquid chamber constant by communicating the sub liquid chamber and the upper chamber, and the upper end position of the small hole is in the sub liquid chamber. A liquid-enclosed engine mount, wherein the liquid-enclosed engine mount is positioned below the liquid level of the liquid sealed in the upper chamber and coincides with the liquid level of the sealed liquid. The liquid-filled engine mount according to claim 1,
A liquid-filled engine mount, characterized in that a throttle portion is provided in a portion desired in the main liquid chamber of the sub liquid chamber . The liquid-filled engine mount according to claim 1,
Of the first and second members, the member with which the peripheral edge of the partition member abuts consists of a bottomed cylindrical member and a cylindrical member coupled by caulking to the opening edge of the bottomed cylindrical member,
A liquid-filled engine mount, wherein a peripheral portion of the partition member is sandwiched by the caulking portion .

Images