JP4815411B2 - Liquid filled vibration isolator - Google Patents

Description

  The present invention relates to an air diaphragm type liquid-filled vibration isolator used to support, for example, an automobile engine.

  2. Description of the Related Art Conventionally, there has been known an air diaphragm type liquid-filled vibration isolator that encloses air together with liquid and omits the diaphragm by utilizing the compression and expansion of the air (Patent Document 1).

  FIG. 5 shows a cross-sectional view of the vibration isolator. In FIG. 5, reference numeral 101 denotes an inner cylinder disposed sideways so that the cylinder axis X is substantially horizontal, and reference numeral 102 denotes the inner cylinder. Reference numeral 103 denotes an outer cylindrical body that surrounds the periphery of 101, reference numeral 103 denotes a rubber elastic body that connects the outer cylindrical body 102 and the inner cylindrical body 101, and reference numeral 104 denotes a rubber elastic body 103 that is embedded to surround the inner cylindrical body 101. Intermediate cylinder.

  Reference numeral 105 denotes a main fluid chamber, and reference numeral 106 denotes a sub fluid chamber. The main fluid chamber 105 and the sub fluid chamber 106 communicate with each other through an orifice 107 and a communication hole 108. The fluid chambers 105 and 106 are filled with a liquid L as an incompressible fluid and air A as a compressible gas. When used, the main fluid is used so that proper vibration-proof performance can be exhibited. The chamber 105 is filled with the liquid L, and the sub fluid chamber 106 is configured to be filled with the liquid L and the air A.

  That is, as shown in (a) of the figure, in the unloaded state where the static load of the supported body is not supported, that is, before use, the upper part of the main fluid chamber 105 has a cross section viewed from the direction of the cylinder axis X. Since the rubber elastic body 103 that spreads in a letter shape is partitioned by a pair of main spring portions 103a and 103b, when the main fluid chamber 105 is placed below and the sub-fluid chamber 106 is placed above, the air A is It accumulates at the top of 106.

Therefore, in this vibration isolator, in order to eliminate the air A accumulated in the upper portion of the main fluid chamber 105 and guide it to the sub fluid chamber 106, the vibration isolator is used to support the static load of the supported body as shown in FIG. When the state is reached, the main spring portions 103a and 103b spreading in a letter C shape are deformed, and the upper portion of the main fluid chamber 105 is inclined upward toward the opening of the communication hole 108 and collected in the main fluid chamber 105. The gas A was introduced into the auxiliary fluid chamber 106 through the communication hole 108.
Japanese Patent No. 3676025

  However, in the above vibration isolator, the rubber elastic body eliminates the gas in the main fluid chamber by utilizing the action of deforming while supporting the static load of the supported body. The shape of the spring part was severely restricted and could not be freely designed for the required performance.

  For example, when it is desired to increase the rigidity in the vertical direction, it is preferable to configure the main spring portion so as to stand on the vertical direction side. However, even if the rubber elastic body is deformed, the depression near the upper center of the main fluid chamber Thus, it becomes difficult to reliably guide the air to the secondary fluid chamber.

  The present invention has been made in view of such a point, and an object of the present invention is to reliably supply gas from the main fluid chamber while increasing the degree of freedom in designing the shape of the rubber elastic body that determines the performance of the vibration isolator. An object of the present invention is to provide a liquid-filled vibration isolator that leads to a fluid chamber and exhibits stable performance.

  In order to achieve the above object, in the present invention, apart from the orifice, an exhaust passage is provided that can exclude gas from the main fluid chamber and guide it to the sub fluid chamber without deformation of the rubber elastic body.

  Specifically, the inner cylinder arranged with the cylinder axis facing sideways, the outer cylinder surrounding the circumference of the inner cylinder, and the inner cylinder and the outer cylinder are interposed between the two. A rubber elastic body to be connected, a main fluid chamber which is partitioned by the rubber elastic body and formed relatively below, a sub fluid chamber formed relatively above, and the main fluid chamber and sub fluid chamber A liquid-filled vibration isolator having an orifice communicating therewith, and a recess serving as a main fluid chamber is formed in the lower portion of the rubber elastic body so as to be formed upward. A lateral exhaust passage that opens and extends laterally outward from the lateral exhaust passage, and a peripheral exhaust passage that is connected to the lateral exhaust passage and extends upward to communicate with the auxiliary fluid chamber are formed.

  According to this configuration, the horizontal exhaust passage extends laterally from the upper end of the upwardly recessed recess that becomes the main fluid chamber, and communicates with the auxiliary fluid chamber formed upward via the peripheral exhaust passage. The gas that accumulates in the main fluid chamber collects in the upper part of the main fluid chamber. Even if the rubber elastic body is not deformed, the collected gas is guided to a lateral exhaust passage extending laterally from the rubber elastic body, Move to secondary fluid chamber.

  Therefore, the shape of the rubber elastic body can be designed relatively freely without being restricted by a specific shape as in the case of the vibration isolator of the above-mentioned Patent Document 1. For example, if the main spring portion is configured to stand in the vertical direction in order to increase the rigidity in the vertical direction, the side surface of the main fluid chamber will also stand in the vertical direction. Absent.

  More specifically, the lateral exhaust passage can be configured by a through hole or a groove opened downward. If the former, the physical properties of the rubber elastic body are hardly impaired, and the spring balance is excellent. If the latter, there is an advantage that molding is easy in terms of die cutting.

  Also, a stopper that protrudes upward is provided at a portion that becomes the floor surface of the main fluid chamber, and a buffer portion that softens the collision of the stopper is provided downward on the inner wall upper portion of the recess that becomes the ceiling surface of the main fluid chamber. A circumferential groove which is formed so as to protrude and is inclined around the buffer portion so as to have the highest connection portion with the lateral exhaust passage can be formed over the entire circumference. By doing so, all the gas accumulated in the main fluid chamber is collected at the connection site with the lateral exhaust passage, and can be more reliably guided to the lateral exhaust passage and eliminated.

  Further, at least in a state where the static load of the supported body is supported, the lateral exhaust passage can be inclined so that the connection portion with the peripheral exhaust passage becomes the highest. By doing so, the gas in the main fluid chamber can be more reliably guided to the sub-fluid chamber. Here, at least in the state where the static load of the supported body is supported, it is intended to include the unloaded state. In this case, since it is inclined before the deformation, it is more reliable. Improves.

  As described above, according to the present invention, the gas that has entered the main fluid chamber can be reliably guided to the sub-fluid chamber while the shape of the rubber elastic body is freely set, and the required performance can be stabilized. Thus, it is possible to provide a liquid-filled vibration isolator that can be exhibited.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature, and is not intended to limit the present invention, its application, or its use.

  As shown in FIGS. 1 to 3, the liquid-filled vibration isolator (hereinafter referred to as a vibration isolator) of the present invention includes a metal inner cylinder 1 having a thin cylindrical shape, and the periphery of the inner cylinder 1. A metal outer cylinder 2 having a cylindrical shape surrounding the rubber, a rubber elastic body 3 having a substantially cylindrical shape interposed between the inner cylinder 1 and the outer cylinder 2 and connected to each other, and the rubber elastic body 3 Are formed in the intermediate cylinder 4 and the outer cylinder 2 which are integrated inside the main fluid chamber 5 and the sub fluid chamber 6 in which the liquid L is sealed, and communicate with the main fluid chamber 5 and the sub fluid chamber 6. An orifice 7, an exhaust passage 8, a plastic lid 9, and the like are provided.

  In this vibration isolator, the inner cylinder 1 is attached to the transmission side of the engine and the outer cylinder 2 is attached to the vehicle body side in a state where the cylinder axis X is turned sideways so that the main fluid chamber 5 is positioned on the lower side. Used. In the following description, the direction such as up and down follows the direction in use, for example, the direction of the cylinder axis X is the front-rear direction.

  As shown in FIG. 1, this vibration isolator is, for example, mainstream in consideration of the amount of air enclosed as a gas A by combining the rubber elastic body 3 and the lid 9 and press-fitting the outer cylinder 2 halfway. It is manufactured by injecting a predetermined amount of liquid L into the body chamber 5 and the sub-fluid chamber 6 and then press-fitting to the end to caulk both ends of the outer cylinder 2 in the cylinder axis direction.

  As shown in FIG. 2, the rubber elastic body 3 has a pair of arc-shaped walls 3c, 3c and an upper wall 3b in the upper part thereof, and is recessed upward in the lower peripheral wall 3d as shown in FIG. A recess 3e is provided.

  Moreover, the rubber elastic body 3 has the inner cylinder body 1 and the intermediate cylinder body 4 integrated by vulcanization molding inside thereof, and as shown in FIG. In addition, the inner cylinder 1 is provided at a portion where the cylinder axis is displaced above the cylinder axis X of the outer cylinder 2 so as to extend in the front-rear direction in parallel with the cylinder axis X. It is provided so as to surround the periphery of the elastic body 3 near the outer periphery. The rubber elastic body 3 is formed with a pair of gaps 3a and 3a extending in the front-rear direction on both the left and right sides of the inner cylinder 1.

  The auxiliary fluid chamber 6 is formed by fitting the rubber elastic body 3 into the outer cylindrical body 2 so as to be surrounded by the upper wall 3b and arc-shaped walls 3c, 3c and the inner wall of the outer cylindrical body 2, The main fluid chamber 5 is formed by fitting the lid 9 into the lower opening of the recess 3e.

  A stopper 9 a that protrudes upward is provided at a substantially central portion of the upper wall of the lid 9 that becomes the floor surface of the main fluid chamber 5. Even if the rubber elastic body 3 is greatly deformed and collides with the stopper 9a, the inner wall upper portion 30 of the concave portion 3e serving as the ceiling surface of the main fluid chamber 5 is opposed to the stopper 9 so as to reduce the impact. A buffer portion 30a protruding downward is provided.

  The rubber elastic body 3 having such a shape is elastically connected between the inner cylinder body 1 and the outer cylinder body 2 with a spring balance in which the rigidity in the vertical direction is increased and the rigidity is increased in the vertical direction. is doing.

  That is, in the rubber elastic body 3, the main spring portions 3f and 3f that can be elastically deformed from the left and right sides of the inner cylinder 1 extend obliquely downward toward the outer cylinder 2 in a symmetrical manner, and mainly the inner cylinder. 1 is configured to receive a load applied between the outer cylindrical body 2 and the outer cylindrical body 2 to be elastically deformed.

  In the use state in which the static load of the engine, which is the supported body, is supported, as shown in FIG. 3B, the inner cylinder 1 and the upper wall 3b are separated, and the spring elastic body 3 is While deforming, the inner cylinder 1 is displaced downward.

  In particular, in the present embodiment, the main spring portions 3f and 3f are both configured to stand up and down from the left and right, so that even when a downward load is large, the main spring portions 3f and 3f are firmly received. . The shapes of the main spring portions 3f and 3f can be freely designed without worrying about the gas A accumulated in the main fluid chamber 5 because the exhaust passage 8 is provided as will be described later.

  As shown in FIGS. 1 and 3, the orifice 7 includes a belt-like groove portion 7 a formed by cutting out a substantially central portion in the front-rear direction of the peripheral wall 3 d of the rubber elastic body 3. It is configured as a belt-like passage that extends in the circumferential direction from one lower end of the main spring portion 3 f and communicates with the auxiliary fluid chamber 6 in a state of being fitted into the cylindrical body 2. Thus, since the passage length of the orifice 7 is relatively long, an excellent anti-vibration effect is exhibited in a low frequency range.

  On the other hand, an exhaust passage 8 that can automatically guide the gas A in the main fluid chamber 5 to the sub-fluid chamber 6 to be eliminated is formed separately from the orifice 7.

  That is, the exhaust passage 8 is composed of a lateral exhaust passage 8a and a peripheral exhaust passage 8b. The lateral exhaust passage 8a is formed at the upper end (the main fluid chamber 5) of the other main spring portion 3f in which the orifice 7 is formed. At the upper end of the concave portion 3e), and extends laterally from there toward the outer periphery.

  As shown in FIGS. 1 and 4, the horizontal exhaust passage 8 a of the present embodiment is a groove opened downward by dividing one main spring portion 3 f of the rubber elastic body 3 into a substantially center in the front-rear direction. It is formed in a shape. The formation of the lateral exhaust passage 8a in the groove shape in this way is advantageous in terms of manufacturing cost and mass productivity because it facilitates die-cutting at the time of molding, and the gas A accumulated in the main fluid chamber 5 is laterally exhausted. It becomes easy to enter, and also functions as an invitation groove for inducing the gas A from the main fluid chamber 5.

  Furthermore, a circumferential groove that is inclined around the buffer portion 30a formed on the inner wall upper portion 30 of the recess 3e, which is the ceiling surface of the main fluid chamber 5, so that the connection portion with the lateral exhaust passage 8a is located highest. 30b is formed over the entire circumference. That is, since the lateral exhaust passage 8a is opened at the highest portion of the circumferential groove 30b, the gas A accumulated in the upper portion of the main fluid chamber 5 is automatically guided to the opening of the lateral exhaust passage 8a through the circumferential groove 30b. Therefore, it is easy to be excluded from the main fluid chamber 5.

  On the other hand, as shown in FIG. 4, the peripheral exhaust passage 8b is cut out sufficiently smaller than the orifice 7 so that the outer peripheral surface of the peripheral wall portion 3d of the rubber elastic body 3 does not substantially function as an orifice. In a state in which the rubber elastic body 3 is fitted into the outer cylindrical body 2, it is connected to the horizontal exhaust passage 8 a at the outer peripheral portion of the rubber elastic body 3, and extends from there to upward in the circumferential direction and communicates with the auxiliary fluid chamber 6. It is comprised so that it may become a passage.

  In the present embodiment, as shown in FIG. 3 (b), when a predetermined static load is applied, the main spring portion 3f is deformed and the upper surface of the lateral exhaust passage 8a is inclined, and the peripheral exhaust passage 8b. Therefore, the gas A accumulated in the main fluid chamber 5 is automatically guided to the sub fluid chamber 6 and can be excluded with certainty. If the lateral exhaust passage 8a is also tilted as described above from the unloaded state, that is, from the molding stage, the above-described effects can be obtained reliably without depending on deformation.

  In addition to these, the communication port 7b of the orifice 7 which is provided at one lower end of the main spring portion 3f and communicates with the main fluid chamber 5 allows the liquid L flowing into the main fluid chamber 5 to flow along the inner wall thereof. It is preferable to provide a substantially upward opening. Then, when the vibration isolator is used, when the liquid L flows into the main fluid chamber 5 through the orifice 7, the main fluid chamber 5 is laterally moved along the inner wall from the lower end portion where the orifice 7 is provided. Since the flow of the liquid L toward the exhaust passage 8a is formed, it is possible to more reliably prevent the gas A from accumulating in the main fluid chamber 5.

  In addition, the vibration isolator concerning this invention is not limited to the said embodiment, The other various structure is included.

  That is, although the horizontal exhaust passage 8a of the above embodiment has a groove shape, it may be a through hole that penetrates the rubber elastic body 3. If it does so, the shape of the main spring part 3f can be made substantially symmetrical with respect to the inner cylinder 1, and a spring balance can be improved.

  In addition, the orifice 7 and the exhaust passage 8 may be formed in the same main spring portion 3f. The rubber elastic body 3 may not include the intermediate cylinder 4 inside.

It is a disassembled perspective view of the liquid enclosure type vibration isolator of this invention. It is the figure which looked at the rubber elastic body of the present invention from the upper part. It is side sectional drawing seen from the cylinder-axis direction of the liquid enclosure type vibration isolator of this invention. (A) shows a no-load state, and (b) shows a state where a load is applied. It is a perspective view which shows the principal part of the rubber elastic body of this invention. It is side sectional drawing seen from the cylinder-axis direction of the conventional liquid enclosure type vibration isolator. (A) shows a no-load state, and (b) shows a state where a load is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner cylinder 2 Outer cylinder 3 Rubber elastic body 3b Upper wall part 3e Concave part 4 Intermediate cylinder 5 Main fluid chamber 6 Subfluid chamber 7 Orifice 8a Lateral exhaust passage 8b Circumferential exhaust passage 9a Stopper 30a Buffer 30b Circumferential groove L Liquid X Tube axis

Claims (5)

An inner cylinder disposed with the cylinder axis facing sideways, an outer cylinder surrounding the inner cylinder, and a rubber elastic body that is interposed between the inner cylinder and the outer cylinder and connects the two to each other A main fluid chamber formed on the lower side, a sub fluid chamber formed on the upper side, and an orifice communicating with the main fluid chamber and the sub fluid chamber. A liquid-filled vibration isolator comprising:
In the lower part of the rubber elastic body, a recess that becomes a main fluid chamber is formed to be recessed upward,
A lateral exhaust passage that opens to the upper end of the recess and extends laterally outward from the lateral exhaust passage, and a peripheral exhaust passage that is connected to the lateral exhaust passage and extends upward to communicate with the auxiliary fluid chamber are formed. A liquid-filled vibration isolator characterized by that. The liquid-filled vibration isolator according to claim 1,
The liquid filled type vibration damping device, wherein the horizontal exhaust passage is formed as a through hole. The liquid-filled vibration isolator according to claim 1,
The liquid filled type vibration damping device, wherein the horizontal exhaust passage is formed as a groove opened downward. In the liquid enclosure type vibration isolator as described in any one of Claims 1-3,
A stopper that protrudes upward is provided at a portion that becomes the floor surface of the main fluid chamber,
On the upper part of the inner wall of the recess that becomes the ceiling surface of the main fluid chamber, a buffering part that softens the collision of the stopper is formed to protrude downward,
A liquid-filled vibration damping device is characterized in that a circumferential groove is formed around the buffer portion so as to incline so that a connection portion with the horizontal exhaust passage is the highest. In the liquid enclosure type vibration isolator as described in any one of Claims 1-4,
A liquid filled type vibration damping device, characterized in that the horizontal exhaust passage is inclined so that the connection portion with the peripheral exhaust passage becomes the highest at least in a state where the static load of the supported body is supported.

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