JP2016138571A - Liquid seal vibration-proof device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid seal vibration-proof device capable of restricting occurrence of cavitation while making a small size of the device.SOLUTION: There is provided a partition member 40 for defining a liquid chamber having working fluid sealed therein into a main liquid chamber 1 and a sub-liquid chamber 2. The partition member 40 comprises an upper plate 41, a lower holder 42, and an elastic partition member 43 held by the upper plate 41 and the lower holder 42 and formed into a substantial square shape as seen from its top plan view. Edges of the elastic partition member 43 are formed with recesses 45, and the lower holder 42 is formed with seats 46 for closing the recesses 45. When a pressure in the main liquid chamber 1 is negative, the edges of the recesses 45 are spaced apart from the seats 46 to form a clearance between it and each of the seats 46 and in turn when a pressure in the main liquid chamber 1 is positive, the edges of the recesses 45 are closely contacted with the seats 46.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a liquid seal vibration isolator used for an engine mount of an automobile.

  Conventionally, what was described in patent document 1 is known as this kind of liquid seal vibration isolator. In this liquid seal vibration isolator, a circular partition member that partitions the main liquid chamber and the sub liquid chamber is provided to absorb the internal pressure of the main liquid chamber. A relief valve is provided on the outer periphery of the partition member.

  In this liquid seal vibration isolator, when the main liquid chamber becomes negative pressure due to the input of excessive amplitude vibration, the liquid in the sub liquid chamber is leaked to the main liquid chamber by opening the relief valve. As a result, the liquid pressure in the main liquid chamber is increased and cavitation is prevented.

  By the way, with the miniaturization of an automobile engine room, there is a demand for miniaturization of the liquid seal vibration isolator. In general, the liquid seal vibration isolator including the liquid seal vibration isolator disclosed in Patent Document 1 has a circular outer shape in plan view, and is likely to cause a reduction in space efficiency. Therefore, development of a liquid seal vibration isolator that takes into account space saving has been studied in which the outer shape is substantially rectangular in plan view. In this liquid seal vibration isolator, it is preferable that the partition member has a substantially quadrangular shape in plan view to secure an area for obtaining high attenuation performance.

JP 2009-52675 A

  However, if the shape of the partition member is substantially rectangular in plan view, it is difficult to make the tightening margin of the seal portion of the partition member constant, and a relief valve for suppressing the occurrence of cavitation should be installed on the outer periphery of the partition member I could not. For this reason, it is necessary to provide a relief valve separately, and there is a problem that the apparatus is increased in size.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a liquid ring vibration isolator capable of suppressing the occurrence of cavitation while reducing the size of the apparatus.

  The liquid seal vibration isolator of the present invention that solves such a problem includes a liquid chamber in which a working liquid is sealed, and a partition member that divides the liquid chamber into a main liquid chamber and a sub liquid chamber. . The partition member includes an upper plate, a lower holder, and an elastic partition member that is sandwiched between the upper plate and the lower holder and is formed in a substantially square shape in plan view. An opening is formed at the edge of the elastic partition member, and a seating portion that closes the opening is formed in the lower holder. When the main liquid chamber is under negative pressure, the edge of the opening is separated from the seating portion to form a gap with the seating portion, and when the main liquid chamber is under positive pressure, the edge of the opening is The seating portion is in close contact with the seating portion.

  In such a liquid seal vibration isolator, when the main liquid chamber is in a negative pressure state, the working liquid is discharged from the sub liquid chamber through the gap formed between the edge of the opening of the elastic partition member and the seating portion. Flows into the liquid chamber. Therefore, it is possible to suitably suppress the occurrence of cavitation while reducing the size of the apparatus.

  Moreover, when the peripheral rib pinched by the upper plate and the lower holder is provided in the peripheral part of the elastic partition member, the peripheral rib may be partially cut out to form the opening. If it does in this way, cavitation generation | occurrence | production can be suppressed suitably by an opening part, ensuring the high attenuation | damping characteristic by the sealing performance by a surrounding rib.

  Moreover, when the peripheral rib pinched by the upper plate and the lower holder is provided in the peripheral part of the elastic partition member, it is good to form an opening part inside a peripheral rib. If it does in this way, the sealing performance by a surrounding rib can improve and it can suppress cavitation generation | occurrence | production suitably by an opening part, ensuring a high attenuation | damping characteristic.

  Moreover, it is good to provide an opening part in the linear part of the peripheral part of an elastic partition member. In this case, the area around the edge of the opening can be ensured as compared with the case where the opening is provided in a portion other than the straight portion of the peripheral portion, for example, a corner portion between the sides. Thereby, the edge part of an opening part can be flexibly separated from a seating part at the time of the negative pressure of a main liquid chamber, and a clearance gap can be formed suitably between seating parts. Therefore, the occurrence of cavitation can be suitably suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, the liquid seal vibration isolator which can suppress cavitation generation | occurrence | production can be obtained, aiming at size reduction of an apparatus.

It is a perspective view which shows the liquid seal vibration isolator which concerns on 1st Embodiment of this invention. It is the sectional view on the AA line of FIG. It is the BB sectional view taken on the line of FIG. It is a figure which shows a partition member, (a) is a top view, (b) is a front view, (c) is a bottom view. It is a disassembled perspective view of a partition member. (A) is CC sectional view taken on the line of Fig.4 (a), (b) is the principal part expanded sectional view of (a). The operation of the partition member will be described, (a) is a cross-sectional view showing the vicinity of the opening at the time of non-leakage, (b) is a cross-sectional view showing the vicinity of the opening at the time of leak. (A) is a figure which shows the effect | action of the opening part provided in the linear part of a peripheral part, (b) is a figure which shows the effect | action of the opening part provided in the curved part of the peripheral part. It is a figure which shows the partition member used for the liquid seal vibration isolator which concerns on 2nd Embodiment of this invention, (a) is a top view, (b) is a front view, (c) is a bottom view. It is an exploded perspective view of a partition member similarly. (A) is the DD sectional view taken on the line of Fig.9 (a), (b) is the principal part expanded sectional view of (a).

  Hereinafter, embodiments of a liquid seal vibration isolator according to the present invention will be described with reference to the drawings. In the following description, when referring to “front / rear” and “up / down”, the direction shown in FIG. 1 is used as a reference, but “front / rear” does not necessarily coincide with the front / rear direction of the vehicle body. In the description, the same reference numerals are used for the same elements, and duplicate descriptions are omitted. In addition, the vertical direction with respect to the liquid seal vibration isolator is a main vibration input direction.

(First embodiment)
As shown in FIG. 1, the liquid seal vibration isolator is a liquid seal type, and as shown in FIG. 1, a first mounting member 10 disposed on the engine (not shown) side that is a vibration source, and a vehicle body side (not shown) on the vibration receiving side. And a second attachment member 20 arranged in the figure) and an insulator 30 connecting them. The liquid seal vibration isolator has a substantially long rectangular shape in a plan view in which the front-rear direction is a long side and the direction orthogonal thereto is a short side.

  The first attachment member 10 is integrally provided on the upper portion of the insulator 30. As shown in FIGS. 2 and 3, the first mounting member 10 is almost entirely embedded in the insulator 30 and vulcanized and bonded to the insulator 30. The first mounting member 10 is made of, for example, an aluminum alloy, and includes a base portion 11 and a frame portion 12 extending upward from the base portion 11 as shown in FIG.

  As shown in FIG. 3, the base 11 has a cross-sectional shape along the short side direction gradually narrowing toward the lower part. The base 11 includes a seat surface 11a on which the bracket is placed. The seating surface 11 a is a flat surface and is covered with the thin portion 30 a of the insulator 30. Bolt holes (not shown) for fixing brackets (not shown, vibration source side parts) that support the engine are formed in the seat surface 11a.

  As shown in FIG. 2, the frame portion 12 is formed integrally with the base portion 11. The outer peripheral surface and inner peripheral surface of the frame portion 12 are covered with an insulator 30. A mounting opening 12 a is formed inside the frame portion 12. The bracket is fixed to the seat surface 11a through the mounting opening 12a.

  As shown in FIG. 2, the insulator 30 includes a recess 31. The recess 31 is opened downward in FIG. 2 and is partitioned by the partition member 40 to become the main liquid chamber 1. An incompressible working liquid is enclosed in the recess 31. The lower end portion of the insulator 30 is fixed to the frame-shaped metal fitting 33.

  The main liquid chamber 1 is partitioned from the sub liquid chamber 2 by a partition member 40. The main liquid chamber 1 and the sub liquid chamber 2 are communicated with each other by an orifice passage 44 formed in the outer peripheral portion of the partition member 40. The orifice passage 44 is set to resonate with respect to, for example, low-frequency vibration. The auxiliary liquid chamber 2 is formed between the diaphragm 3 and the partition member 40, and the diaphragm 3 is a part of the wall portion.

  The second mounting member 20 includes a long rectangular cylindrical outer cylinder fitting 21. The second attachment member 20 is attached to the vehicle body side by fitting the outer cylinder fitting 21 to a holder (not shown), or attached to the vehicle body side via a bracket member (not shown). As shown in FIG. 2, the upper end portion 21 a of the outer cylindrical metal member 21 has a flange shape, abuts the lower surface of the frame-shaped metal member 33, and sandwiches the extending portion 30 b of the insulator 30 together with the frame-shaped metal member 33. Yes. Moreover, the upper end part 21a of the outer cylinder metal fitting 21 is extended in the substantially L shape to the upper inner side in a different side surface, as shown in FIG. The upper end 21 a is fitted in a recess 33 b provided in the frame-shaped metal fitting 33. The extending portion 30 b of the insulator 30 positions the outer peripheral end portion of the upper surface of the partition member 40.

  The diaphragm 3 includes a thin main body portion 3a and a seal portion 3b integrally formed on the outer peripheral portion thereof. The seal portion 3 b is attached to the outer peripheral end portion of the lower surface of the partition member 40 and is interposed between the outer cylinder fitting 21 and the partition member 40.

  In order to assemble this liquid seal vibration isolator, first, a small assembly in which the first mounting member 10 and the insulator 30 are integrated is formed, and this is turned upside down from the state shown in FIG. The outer peripheral end of the upper surface of the member 40 is placed and positioned. Subsequently, the seal portion 3 b of the diaphragm 3 is attached to the outer peripheral end portion of the lower surface of the partition member 40. Then, the outer cylinder fitting 21 is put on the diaphragm 3 and the partition member 40, and the extended portion 21 b (see FIGS. 1 and 3) of the upper end portion of the outer cylinder fitting 21 is fitted into the recess 33 b of the frame-like fitting 33. Thereby, the whole is assembled and integrated.

  Next, the partition member 40 will be described in detail. As shown in FIG. 4A, the partition member 40 has a substantially long rectangular shape in plan view, corresponding to the outer shape of the liquid seal vibration isolator. As shown in FIG. 5, the partition member 40 is configured by sandwiching an elastic partition member 43 between an upper plate 41 and a lower holder 42. The elastic partition member 43 has an opening 45 constituting a relief valve (see FIG. 5). The orifice passage 44 described above is provided at a site on the outside of the elastic partition member 43 (see FIGS. 2 and 3).

  The upper plate 41 and the lower holder 42 are made of an appropriate material such as a light metal such as an aluminum alloy or a hard resin. As shown in FIG. 5, the upper plate 41 has a plate shape. The upper plate 41 has a raised portion 41a whose inner portion is one step higher. As shown in FIG. 4A, a plurality of through holes 41b and 41c are formed in the raised portion 41a. The upper surface of the flat plate portion 43a (see FIG. 5) of the elastic partition member 43 faces the through hole 41b, and a part of the opening 45 of the elastic partition member 43 faces the through hole 41c. Thus, the upper surface of the elastic partition member 43 faces the main liquid chamber 1 through the plurality of through holes 41b and 41c. A communication hole 44 a that communicates with the orifice passage 44 is formed in the outer peripheral portion of the upper plate 41. Further, as shown in FIG. 6B, a circumferential groove 41f (only a part is shown in the cross section) is formed on the lower surface of the upper plate 41.

  As shown in FIG. 5, a concave orifice passage 44 is formed on the outer peripheral portion of the lower holder 42. A mounting portion 42e to which the elastic partition member 43 is mounted is formed in the inner portion of the orifice passage 44. A circumferential groove 42f is formed in the peripheral portion of the mounting portion 42e (see FIG. 6B). The circumferential groove 42f is formed to face the circumferential groove 41f of the upper plate 41. As shown in FIG. 4C, a plurality of through holes 42b and 42c are formed in the mounting portion 42e. The lower surface of the flat plate portion 43a of the elastic partition member 43 faces the through holes 42b and 42c. As a result, the lower surface of the elastic partition member 43 faces the secondary liquid chamber 2 through the plurality of through holes 42b and 42c. The through hole 42 c is located closer to the center of the elastic partition member 43 than the edge 45 b (see FIG. 5) of the opening 45 of the elastic partition member 43. That is, the opening 45 is not positioned (does not face) in the through hole 42c. A flat seat 46 is formed between the through hole 42c and the circumferential groove 42f. A communication hole 44 b that communicates with the orifice passage 44 is formed in the outer peripheral portion of the lower holder 42.

  The elastic partition member 43 is made of an elastic member such as rubber and has a substantially rectangular shape in plan view (substantially oval shape in plan view). The elastic partition member 43 has a long side extending in the front-rear direction and a short side extending in a direction orthogonal to the long side. As shown in FIG. 5, the elastic partition member 43 includes a flat plate portion 43 a and a peripheral rib 43 b that protrudes in the vertical direction along the peripheral edge portion of the flat plate portion 43 a. The flat plate portion 43a is a pressure receiving portion that receives the hydraulic pressure of the main liquid chamber 1, and has a flat surface shape. The flat plate portion 43a absorbs the internal pressure change by elastically deforming in response to the internal pressure change of the main liquid chamber 1.

  Openings 45, 45 are formed on both short sides (straight line portions) of the elastic partition member 43. The opening 45 has a shape in which the outer periphery is notched inward, and has a substantially planar shape including a side edge 45a, 45a along the front-rear direction and an end edge 45b continuous to the side edge 45a, 45a. It is demarcated by a letter-shaped edge. The side edge portions 45a and 45a are located closer to the central portion of the elastic partition member 43 than the peripheral rib 43b. The opening 45 is formed at a position corresponding to the seating portion 46 of the lower holder 42, and has an opening area smaller than the area of the seating portion 46.

  At the time of positive pressure in the main liquid chamber 1 (see FIG. 2, the same applies hereinafter), the edges (side edges 45 a and 45 a and the edge 45 b) of the opening 45 are seated by the elastic partition member 43 due to elastic deformation. Adhere (sit) against. As a result, the opening 45 is closed. Further, at the time of negative pressure in the main liquid chamber 1, the edges (side edges 45 a and 45 a and end edge 45 b) of the opening 45 are separated (separated) from the seat 46 due to elastic deformation of the elastic partition member 43. As a result, a gap is formed between the edge of the opening 45 and the seat 46.

7A and 7B illustrate the operation of the elastic partition member. FIG. 7A is a cross-sectional view showing the vicinity of the opening at the time of non-leakage, and FIG. 7B is a cross-sectional view showing the vicinity of the opening at the time of leak.
The opening 45 of the elastic partition member 43 opens and closes due to elastic deformation of the vicinity of the side edge portions 45a and 45a and the end edge portion 45b. The elastic partition member 43 is disposed in a normal state with a gap S2 between the upper plate 41 and a gap S3 with the lower holder 42 as shown in FIG. 6B. ing. That is, the elastic partition member 43 is disposed in a normal state without being in close contact with either the upper plate 41 or the lower holder 42.

  When a large vibration is input to the first mounting member 10, the main liquid chamber 1 is compressed and the working liquid is sent out to the sub liquid chamber 2 side. At this time, the working liquid in the main liquid chamber 1 is pressurized and pushes the upper surface of the elastic partition member 43 to the lower sub liquid chamber 2 side as shown in FIG. As a result, the entire elastic partition member 43 is elastically deformed downward, and the vicinity of the side edges 45a and 45a and the vicinity of the end edge 45b of the opening 45 of the elastic partition member 43 are elastically deformed. Sit against the seat 46. As a result, the opening 45 is closed and the sealing performance is improved. In addition, the vicinity of the side edge portions 45a and 45a and the vicinity of the end edge portion 45b are easily deformed because they are edge portions, and are suitably bulged and deformed downward by the hydraulic pressure of the working liquid. Therefore, it is difficult to cause a leak from the main liquid chamber 1 to the sub liquid chamber 2. Therefore, at the time of positive pressure in the main liquid chamber 1, the working hydraulic pressure is satisfactorily attenuated by elastic deformation of the elastic partition member 43 and liquid column resonance by the orifice passage 44.

  Thereafter, when the vibration direction is reversed and the volume of the main liquid chamber 1 returns to the state before compression, the working liquid moves through the orifice passage 44, so that the return is delayed and the inside of the main liquid chamber 1 is instantaneous. Approaches the negative pressure state. FIG. 7B shows this state, in which the elastic partition member 43 is pulled from the main liquid chamber 1 side, and the working liquid on the sub liquid chamber 2 side is in the vicinity of the side edges 45a and 45a of the opening 45 and the end. Push up the vicinity of the edge 45b. As a result, the vicinity (edge) of the side edges 45a and 45a of the opening 45 and the vicinity (edge) of the end edge 45b tend to be gradually turned, and eventually the main liquid chamber 1 and When the pressure due to the hydraulic pressure difference with the sub liquid chamber 2 exceeds the rigidity around the opening 45, the opening 45 is separated from the seat 46. By this separation, the opening 45 forms a gap with the seat 46, and leaks the working liquid on the sub liquid chamber 2 side to the main liquid chamber 1 side. Therefore, the pressure in the main liquid chamber 1 is increased, and the occurrence of cavitation in the main liquid chamber 1 is suppressed.

  Note that the internal pressure level of the main liquid chamber 1 serving as a reference for leakage through the opening 45 can be adjusted by the hardness of the elastic partition member 43.

  According to the liquid seal vibration isolator of the present embodiment described above, when the main liquid chamber 1 is in a negative pressure state, the gap formed between the edge of the opening 45 of the elastic partition member 43 and the seat 46. Through this, the working liquid flows from the secondary liquid chamber 2 to the main liquid chamber 1. Therefore, it is possible to suitably suppress the occurrence of cavitation while reducing the size of the apparatus.

  Further, since the opening 45 is formed by partially cutting the peripheral rib 43b, the opening 45 suitably suppresses the occurrence of cavitation while ensuring a high damping characteristic by the sealing performance by the peripheral rib 43b. Can do.

  Moreover, since the opening part 45 is provided in the linear part (both short sides) of the peripheral part of the elastic partition member 43, the following effects are obtained. That is, as shown in FIG. 8A, in the present embodiment, since the opening 45 is provided in the straight line portion of the peripheral edge of the elastic partition member 43, the angle between the side edge 45a and the peripheral rib 43b. The angle α1 of the part is approximately 90 degrees (right angle). On the other hand, as shown in FIG. 8B, when the opening 45 is provided in a portion other than the straight portion, for example, a corner portion (curved portion) of the long side and the short side. The angle α2 at the corner between the side edge 45a and the peripheral rib 43b is less than about 90 degrees (acute angle). For this reason, when the angle α2 is set as compared with the case where the angle α1 is set, the area around the corner portion becomes small, and the side edge portions 45a and 45a are hardly elastically deformed.

  On the other hand, in the present embodiment, since the opening 45 is provided in the straight portion, the area around the corner can be increased as compared with the case where the opening 45 is provided in the curved portion as described above. As a result, the side edge portions 45a and 45a can be elastically deformed flexibly, and cavitation can be suitably suppressed.

(Second Embodiment)
A liquid seal vibration isolator according to a second embodiment of the present invention will be described with reference to FIGS. This embodiment is different from the first embodiment in that the opening 45 is provided on the inner side of the peripheral rib 43b.

  In the present embodiment, as shown in FIG. 10, in the elastic partition member 43, the circumferential rib 43 b is provided in the entire circumferential direction (without being cut out). The opening 45 is provided inside the circumferential rib 43b without partially cutting out the circumferential rib 43b. Therefore, the opening 45 is located closer to the center of the elastic partition member 43 than in the first embodiment. The opening 45 has a substantially rectangular shape in plan view.

  The opening 45 has a shape in which the flat plate portion 43a is cut out in a hole shape, and includes side edge portions 45a and 45a along the front-rear direction, an end edge portion 45b continuous to the side edge portions 45a and 45a, and a peripheral edge. The rib 43b is partitioned by a substantially square-shaped edge portion in plan view. The opening 45 is formed at a position corresponding to the seating portion 46 of the lower holder 42, and has an opening area smaller than the area of the seating portion 46. As described above, the opening 45 is located closer to the center of the elastic partition member 43 than that of the first embodiment. Therefore, in this embodiment, the opening 45 is shown in FIGS. Thus, the through-hole 42c (refer FIG.4 (c), FIG.5) of the side of the seating part 46 of the lower holder 42 is not formed.

  At the time of positive pressure in the main liquid chamber 1 (see FIG. 2, the same applies hereinafter), the seat portion 46 is formed by elastic deformation of the elastic partition member 43 at the edges (side edges 45a, 45a and end edges 45b) of the opening 45. Adhere (sit) against. As a result, the opening 45 is closed. Further, at the time of negative pressure in the main liquid chamber 1, the edges (side edges 45 a and 45 a and end edge 45 b) of the opening 45 are separated (separated) from the seat 46 due to elastic deformation of the elastic partition member 43. As a result, a gap is formed between the edge of the opening 45 and the seat 46.

  Also in this embodiment, the same effects as those described in the first embodiment can be obtained. In addition, since the opening 45 is provided on the inner side of the peripheral rib 43b without partially cutting away the peripheral rib 43b, the sealing performance by the peripheral rib 43b is enhanced, and high damping characteristics are secured. Cavitation can be suitably suppressed by the opening 45.

As mentioned above, although embodiment of this invention was described, this invention is not limited to above-described embodiment, It can change variously.
For example, in each of the embodiments described above, the openings 45 are provided on both short sides, but the present invention is not limited to this, and may be provided on both long sides.

  Moreover, the shape of the opening part 45 can employ | adopt the thing of various shapes, such as substantially V shape and substantially semicircle shape by planar view.

  Further, in each of the embodiments, the liquid seal vibration isolator has a substantially long rectangular shape in plan view, and the shapes of the partition member 40 and the elastic partition member 43 are also substantially long rectangular shapes in plan view. However, the present invention is not limited to this. Each part may have a square shape, or a portion having a substantially rectangular shape in plan view and a square portion may be mixed and used.

DESCRIPTION OF SYMBOLS 1 Main liquid chamber 2 Sub liquid chamber 10 1st attachment member 20 2nd attachment member 30 Insulator 40 Partition member 41 Upper plate 42 Lower holder 43 Elastic partition member 43b Peripheral rib 45 Opening 45a Side edge (edge)
45b End edge (edge)
46 Seating

Claims (4)

A liquid chamber in which a working liquid is enclosed;
A partition member that divides the liquid chamber into a main liquid chamber and a sub liquid chamber,
The partition member includes an upper plate, a lower holder, and an elastic partition member sandwiched between the upper plate and the lower holder and formed in a substantially square shape in plan view.
An opening is formed at the edge of the elastic partition member,
The lower holder is formed with a seating portion that closes the opening,
When the main liquid chamber is under negative pressure, the edge of the opening is separated from the seating portion to form a gap with the seating portion, and when the main liquid chamber is under positive pressure, the edge of the opening is A liquid seal vibration isolator which is in close contact with the seating portion. A peripheral rib sandwiched between the upper plate and the lower holder is provided at the peripheral edge of the elastic partition member,
The liquid seal vibration isolator according to claim 1, wherein the opening is formed by partially cutting the peripheral rib. A peripheral rib sandwiched between the upper plate and the lower holder is provided at the peripheral edge of the elastic partition member,
The liquid seal vibration isolator according to claim 1, wherein the opening is formed inside the peripheral rib.   4. The liquid seal vibration isolator according to claim 2, wherein the opening is provided in a linear portion of a peripheral edge of the elastic partition member. 5.

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