JP7500407B2 - Liquid-filled anti-vibration device - Google Patents

Description

The present invention relates to a liquid-filled vibration-proof device, and in particular to a liquid-filled vibration-proof device that can reduce the space required for a switching valve.

As an example of an anti-vibration device that supports a vibration source such as an engine on a vehicle body, a liquid-filled anti-vibration device disclosed in Patent Document 1 is known. The liquid-filled anti-vibration device disclosed in Patent Document 1 comprises a first mounting fixture attached to the vibration source side (engine side), a cylindrical second mounting fixture attached to the vehicle body side (support side), and an anti-vibration base that connects the first mounting fixture and the second mounting fixture. Furthermore, with this liquid-filled anti-vibration device, a liquid chamber is formed between the diaphragm attached to the second mounting fixture and the anti-vibration base, and this liquid chamber is divided into a first liquid chamber and a second liquid chamber by a partition.

The first and second orifices communicate with each other, and the second orifice is switched between a connected and blocked state by a switching valve. This switching valve blocks the second orifice when a pair of valve bodies extending from a holding section held by a partition abut against each other due to the liquid pressure difference that occurs between the first and second liquid chambers when large amplitude vibration is input. On the other hand, the shape and rigidity of the valve bodies integrated into the holding section are set so that the valve bodies do not abut against each other due to the liquid pressure difference that occurs when small amplitude vibration is input.

JP 2019-060395 A

However, in the technology disclosed in the above-mentioned Patent Document 1, a switching valve that can switch between a connected state and a blocked state depending on the fluid pressure difference between the first fluid chamber and the second fluid chamber is constructed by sandwiching and holding a holding portion that is integrated with the valve body between a partition body, which creates the problem that it is difficult to reduce the space required for the switching valve by providing the holding portion.

The present invention has been made to solve the above-mentioned problems, and aims to provide a liquid-filled vibration isolation device that can reduce the space required for the switching valve.

In order to achieve this object, the liquid-filled vibration-damping device of the present invention comprises a first mounting fixture and a cylindrical second mounting fixture, an elastic vibration-damping base connecting the first mounting fixture and the second mounting fixture, a diaphragm made of an elastic material attached to the second mounting fixture and forming a liquid chamber filled with liquid between the diaphragm and the vibration-damping base, a partition body dividing the liquid chamber into a first liquid chamber and a second liquid chamber, a first orifice and a second orifice respectively connecting the first liquid chamber and the second liquid chamber, and a changeover valve for switching between a connected state and a blocked state of the second orifice, The valve body comprises a spherical accommodating space having openings communicating with a first liquid chamber and the second liquid chamber, which form a part of the second orifice; a valve body which is a sphere having an inner diameter smaller than that of the accommodating space and is movably accommodated within the accommodating space and which brings the second orifice into a blocked state by abutting against the wall surface of the accommodating space around the opening ; and a plurality of protrusions made of an elastic material which protrude radially from the valve body. When the valve body is left stationary with no vibration input, the protrusions separate the valve body from the wall surface of the accommodating space, bringing the second orifice into a connected state.

According to the liquid-filled vibration-proof device of claim 1, the accommodation space having openings connected to the first and second liquid chambers respectively forms a part of the second orifice, and the valve body is movably accommodated in the accommodation space. In a stationary state without vibration input, the valve body and the wall surface of the accommodation space are separated by a plurality of elastic protrusions protruding from the valve body, and the second orifice is in a communicating state. When the vibration-proof base, which is a part of the wall surface of the liquid chamber, is deformed due to the input of vibration to the liquid-filled vibration-proof device, a liquid pressure difference occurs between the first and second liquid chambers, and a liquid flow corresponding to the liquid pressure difference occurs in the second orifice. If this liquid pressure difference is large, the elastic protrusions are deformed, and the valve body abuts against the wall surface of the accommodation space around the opening (hereinafter referred to as the "valve seat"), closing the switching valve and blocking the second orifice.

On the other hand, if the liquid pressure difference is small, the protrusion keeps the valve body and the valve seat apart, i.e., the switching valve is kept open, and the second orifice can be kept in communication. The switching valve configured as described above can switch the second orifice between a communication state and a cutoff state (opening and closing of the switching valve) by the movable and self-supporting valve body. Therefore, the switching valve can be made more space-saving than a switching valve in which a retaining portion integrated with the valve body is sandwiched between a partition body or the like to retain the retaining portion.
The valve disc is a sphere with an inner diameter smaller than the spherical accommodation space. Since multiple protrusions extend radially from the valve disc, the valve disc can be kept separated from the valve seat with a simple configuration when the liquid pressure difference is small. Furthermore, since the changeover valve has such a simple configuration, the magnitude of the liquid pressure difference at which the valve disc and the valve seat come into contact can be easily adjusted depending on the thickness, length, number, etc. of the protrusions. This makes it easier to design the changeover valve, such as the opening and closing timing.

According to the liquid-filled vibration-proof device described in claim 2, the valve body is an elastic body that is molded integrally with the protrusion. This makes it easier to manufacture the valve body with the protrusion, in addition to the effect of claim 1. Furthermore, even if the protrusion is pinched between the valve body and the valve seat when the switching valve is closed, the valve body elastically deforms, making it easier to seal between the valve body and the protrusion and the valve seat.

According to the liquid-filled vibration-proof device described in claim 3, the opening on the first liquid chamber side and the opening on the second liquid chamber side face each other on both sides of the valve body. A plurality of protrusions are arranged on the valve body and abut against the wall surface of the accommodation space so that the valve body is located in the center of the accommodation space in a cross section perpendicular to the opposing direction of the opening on the first liquid chamber side and the opening on the second liquid chamber side. This causes the valve body to move in the opposing direction of the two openings, and the switching valve opens and closes in response to the liquid pressure difference with almost no movement of the valve body in the direction perpendicular to the opposing direction. Therefore, in addition to the effects of claim 1 or 2, the timing at which the switching valve opens and closes in response to the liquid pressure difference can be stabilized.

FIG. 2 is a cross-sectional view of a liquid-filled vibration isolation device according to one embodiment. 2 is a cross-sectional view of the liquid-filled vibration isolating device taken along line II-II in FIG. 1. FIG.

A preferred embodiment will now be described with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of a liquid-sealed vibration-damping device 10 in one embodiment. FIG. 1 shows the liquid-sealed vibration-damping device 10 in a stationary state before it supports an engine (i.e., before the weight of the engine is added), in which no vibration is input to the liquid-sealed vibration-damping device 10. In the following description, the upper side of the paper in FIG. 1 will be described as the upper side of the liquid-sealed vibration-damping device 10, but the top and bottom of the liquid-sealed vibration-damping device 10 do not necessarily coincide with the top and bottom of the vehicle to which the liquid-sealed vibration-damping device 10 is attached.

The hydraulic vibration-proof device 10 is an engine mount that elastically supports an automobile engine. The hydraulic vibration-proof device 10 mainly comprises a first mounting fixture 11 that is attached to the engine (not shown) side, which is the vibration source, a cylindrical second mounting fixture 12 that is attached to the vehicle body (not shown) on the support side, and a vibration-proof base 13 composed of an elastic body that connects the first mounting fixture 11 and the second mounting fixture 12. Note that the cross-sectional view of the hydraulic vibration-proof device 10 in Figure 1 is an axial cross-sectional view including the axis C of the cylindrical second mounting fixture 12.

The first mounting fixture 11 is a boss metal fitting arranged on the axis C of the second mounting fixture 12 so as to be located above the second mounting fixture 12, and is made of a metal such as steel or an aluminum alloy. A bolt hole (not shown) is formed in the upper end surface of the first mounting fixture 11. The first mounting fixture 11 is attached to the engine side via a bolt (not shown) that is attached to the bolt hole.

The second mounting fixture 12 is a cylindrically shaped member, and is mainly made of metal such as steel. The second mounting fixture 12 has a large diameter portion 12a at the upper end, a reduced diameter portion 12b that is connected to the lower end of the large diameter portion 12a and has gradually smaller inner and outer diameters going downward, and a small diameter portion 12c that is connected to the lower end of the reduced diameter portion 12b and has smaller inner and outer diameters than the large diameter portion 12a. The second mounting fixture 12 is attached to the vehicle body by fitting the small diameter portion 12c into a cylindrical bracket provided on the vehicle body and supporting the reduced diameter portion 12b from below with the bracket.

The vibration-isolating base 13 is a member made of an elastic material such as rubber or a thermoplastic elastomer formed into a roughly umbrella shape. The vibration-isolating base 13 is vulcanization-bonded to the lower part of the first mounting fixture 11 and to the inner circumferential surfaces of the large diameter portion 12a and the reduced diameter portion 12b, connecting them together. A rubber membrane-like sealing wall portion 14 that covers the inner circumferential surface of the small diameter portion 12c is connected to the lower end of the vibration-isolating base 13. This sealing wall portion 14 is part of the second mounting fixture 12.

A diaphragm 15 is attached to the second mounting fixture 12 via the mounting portion 16 so as to close the lower end opening of the small diameter portion 12c. The diaphragm 15 is a membrane made of an elastic material such as rubber. The mounting portion 16 is an annular member made of a metal such as steel. The outer periphery of the diaphragm 15 is vulcanization bonded all around the inner periphery of the mounting portion 16.

A liquid chamber is formed by the sealed space partitioned by the vibration-isolating base 13, the second mounting fixture 12, and the diaphragm 15. An antifreeze liquid (not shown) such as ethylene glycol is sealed in the liquid chamber. The liquid chamber is partitioned by a partition 20 into a first liquid chamber 17, in which the vibration-isolating base 13 forms part of the chamber wall, and a second liquid chamber 18, in which the diaphragm 15 forms part of the chamber wall.

To attach the diaphragm 15 and the partition 20 to the second mounting fixture 12, first, the partition 20 is inserted into the small diameter portion 12c of the second mounting fixture 12 until it contacts the step 13a of the vibration-isolating base 13 that protrudes radially inward from the upper end of the sealing wall portion 14. Next, the mounting portion 16 to which the diaphragm 15 is integrated is inserted into the small diameter portion 12c, and the small diameter portion 12c is then reduced in diameter by drawing, and the outer periphery of the partition 20 and the mounting portion 16 is held by the sealing wall portion 14. This attaches the diaphragm 15 and the partition 20 to the second mounting fixture 12.

The partition body 20 includes a cylindrical member 21 whose upper end is held inside the sealing wall portion 14 by contacting the step 13a, flat plate-shaped partition members 24, 25 that separate the inner periphery of the cylindrical member 21 into upper and lower parts, and a switching valve 30 provided in part of the partition members 24, 25. The partition member 24 facing the first liquid chamber 17 and the partition member 25 facing the second liquid chamber 18 are stacked one on top of the other and joined by welding or adhesive.

The tubular member 21 is a cylindrical member made of metal or synthetic resin. The tubular member 21 is integrally molded with the partition members 24, 25, and is formed by joining upper and lower members together, just like the partition members 24, 25. The outer peripheral surface of the tubular member 21 is pressed against the small diameter portion 12c of the second mounting fixture 12 via the seal wall portion 14 over the entire circumference.

A peripheral groove 22 having a length of approximately two circumferences is formed on the outer peripheral surface of the cylindrical member 21. A first orifice 19 is formed between this peripheral groove 22 and the seal wall portion 14. One end of the peripheral groove 22 opens at the upper end of the cylindrical member 21 radially inward from the step 13a, so that the first orifice 19 communicates with the first liquid chamber 17. The other end of the peripheral groove 22 opens at the lower end of the cylindrical member 21 radially inward from the contact position with the diaphragm 15, so that the first orifice 19 communicates with the second liquid chamber 18.

In this way, the first orifice 19 is a flow passage that connects the first fluid chamber 17 and the second fluid chamber 18. The flow passage cross-sectional area, length, cross-sectional circumference, etc. of the first orifice 19 are set so that the damping coefficient is large in a frequency band corresponding to the shake vibration (e.g., about 5 to 15 Hz) when a large amplitude shake vibration is input, for example, in order to damp shake vibrations when the vehicle is running.

The switching valve 30 will be described with reference to Figs. 2 and 3 in addition to Fig. 1. Fig. 2 is a cross-sectional view of the liquid-filled vibration-proof device 10 taken along line II-II in Fig. 1, and is a partially enlarged cross-sectional view showing the switching valve 30 in an enlarged manner. Fig. 3 is a perspective view of the valve body 38 and the protrusion 39.

The switching valve 30 is disposed at a position closer to the outer periphery than the center of the partition members 24, 25. The switching valve 30 includes a hemispherical dome portion 31 whose outer periphery is connected to the partition member 24 and bulges upward from the partition member 24, a hemispherical dome portion 32 whose outer periphery is connected to the partition member 25 and bulges downward from the partition member 25, a valve body 38 housed in a spherical housing space 35 formed by the inner walls of the dome portions 31, 32, and a plurality of protrusions 39 protruding from the valve body 38.

The valve body 38 is inserted between the dome portions 31, 32 of the partition members 24, 25 before they are joined together, without pinching the protrusions 39. The partition members 24, 25 are then stacked and joined together, forming the partition body 20 with the switching valve 30.

As shown in Figures 1 and 2, an opening 33 that opens into the storage space 35 and the first liquid chamber 17 is formed through the apex of the dome portion 31. The storage space 35 and the first liquid chamber 17 are connected by a flow path 36 formed by this opening 33. Similarly, an opening 34 that opens into the storage space 35 and the second liquid chamber 18 is formed through the apex of the dome portion 32. The storage space 35 and the second liquid chamber 18 are connected by a flow path 37 formed by this opening 34. The openings 33, 34 (flow paths 36, 37) face each other vertically with the valve body 38 in between.

The accommodation space 35 and the flow paths 36, 37 form a second orifice that connects the first fluid chamber 17 and the second fluid chamber 18. The flow path cross-sectional area, length, cross-sectional circumference, etc. of this second orifice (particularly the flow paths 36, 37) are set so that the damping coefficient is large in the frequency band corresponding to the idle vibration (e.g., about 15 to 50 Hz) when a small amplitude idle vibration is input, for example, in order to reduce the idle vibration during idling (when the vehicle is stopped).

The switching valve 30 switches between the open and closed states of this second orifice. By opening the switching valve 30 and opening the second orifice during small amplitude idle vibration, the idle vibration can be reduced by the second orifice. On the other hand, by closing the switching valve 30 and closing the second orifice during large amplitude shake vibration, the liquid passes through the first orifice 19, and the vibration damping effect of the first orifice 19 can be effectively achieved.

The valve element 38 is a sphere made of an elastic material for blocking the flow paths 36, 37 to close the switching valve 30 and to shut off the second orifice. Since the diameter D1 of the valve element 38 is smaller than the diameter D2 of the spherical accommodation space 35, the valve element 38 can be moved within the accommodation space 35. Furthermore, since the diameter D1 of the valve element 38 is larger than the diameter D3 of the flow paths 36, 37 (openings 33, 34), the valve element 38 can be brought into contact with the wall surface of the accommodation space 35 around the openings 33, 34 (hereinafter referred to as "valve seats 31a, 32a") to block the flow paths 36, 37.

Furthermore, since the diameter D1 of the valve body 38 is larger than the diameter D3 of the flow paths 36, 37, the valve body 38 moving within the accommodation space 35 can be made less likely to be released from the flow paths 36, 37 into the first liquid chamber 17 or the second liquid chamber 18. It is preferable that the diameter D1 is 1.1 times or more the diameter D3. Although it depends on the hardness of the elastic body constituting the valve body 38, if the diameter D1 is 1.1 times or more the diameter D3, it is possible to sufficiently make it difficult for the valve body 38 to be released from the flow paths 36, 37.

As shown in Figures 1 to 3, the multiple protrusions 39 are rod-shaped elastic parts that are distributed so as to extend radially from the valve body 38, and are molded integrally with the valve body 38. This makes it easier to manufacture the valve body 38 with the protrusions 39. The length L1 of the protrusions 39 is set to be at least twice the thickness (diameter) D4 of the protrusions 39. In addition, the length L1 of the protrusions 39 is set to be approximately the same as the difference between the diameter D1 of the valve body 38 and the diameter D2 of the storage space 35. This allows the tips of the protrusions 39 to contact the wall surface of the storage space 35.

In this embodiment, 14 protrusions 39 are provided. Specifically, a total of six protrusions 39 are located on each side of the valve body 38 on the X-axis, Y-axis, and Z-axis that pass through the center of the valve body 38 and are perpendicular to one another. Furthermore, in the XY plane, a total of four protrusions 39 are located at each of the midpoints between the two protrusions 39 on the X-axis and the two protrusions 39 on the Y-axis. Furthermore, in the XZ plane, a total of four protrusions 39 are located at each of the midpoints between the two protrusions 39 on the X-axis and the two protrusions 39 on the Z-axis.

Since multiple protrusions 39 are thus distributed around the valve body 38, in a stationary state with no vibration input, the protrusions 39 separate the valve body 38 from the wall surface of the accommodation space 35, including the valve seats 31a, 32a. This opens the switching valve 30, and the second orifice (the accommodation space 35 and the flow paths 36, 37) comes into communication. In particular, when the accommodation space 35 is spherical and the valve body 38 is spherical, if there are a total of six protrusions 39 on the X-axis, Y-axis, and Z-axis, the valve body 38 can be reliably separated from the valve seats 31a, 32a, and the communication state of the second orifice can be reliably maintained.

When vibration is input to the liquid-filled vibration-proof device 10, the first liquid chamber 17 contracts or expands as the vibration-proof base 13 deforms, and a liquid pressure difference occurs between the first liquid chamber 17 and the second liquid chamber 18. A liquid flow corresponding to this liquid pressure difference occurs in the second orifice, and the pressure associated with the liquid flow acts on the valve body 38. If the liquid pressure difference is large, the elastic protrusion 39 deforms, and the valve body 38 abuts against the valve seats 31a, 32a, closing the switching valve 30. This causes the second orifice to be blocked. Note that when liquid flows from the first liquid chamber 17 to the second liquid chamber 18, the valve body 38 abuts against the valve seat 32a, and when liquid flows from the second liquid chamber 18 to the first liquid chamber 17, the valve body 38 abuts against the valve seat 31a.

On the other hand, if the liquid pressure difference is small, the valve body 38 and the valve seats 31a, 32a are separated by the protrusion 39, i.e., the switching valve 30 is maintained in an open state, as in the stationary state, and the second orifice can be maintained in a connected state. The switching valve 30 configured as described above can switch the second orifice between a connected state and a blocked state (opening and closing of the switching valve 30) by the movable and self-supporting valve body 38, so the switching valve 30 can be made more space-saving than conventional switching valves in which a retaining portion integrated with the valve body is held by sandwiching it between a partition body or the like.

Since the protrusion 39 is made of an elastic body, when the switching valve 30 is closed due to a large hydraulic pressure difference, the valve body 38 abuts against the valve seats 31a and 32a while the protrusion 39 is elastically deformed. Therefore, the impact caused by this abutment can be mitigated by the elastic deformation of the protrusion 39.

In particular, when the protrusion 39 is sandwiched between the valve body 38 and the wall surface of the storage space 35 in the vertical direction, which is the direction in which the openings 33, 34 (flow paths 36, 37) face each other and in which the valve body 38 moves, when the switching valve 30 is closed, the protrusion 39 is crushed as the valve body 38 moves up and down and comes into contact with the valve seats 31a, 32a. This allows the collapse of the protrusion 39 to further reduce the impact when the valve body 38 comes into contact with the valve seats 31a, 32a.

In this embodiment, there are eight protrusions 39 spaced equally apart on each of two mutually orthogonal planes (the XY plane and the XZ plane in this embodiment). This ensures that the protrusions 39 are securely sandwiched between the valve body 38 and the wall surface of the accommodation space 35 in the vertical direction even if the valve body 38 rotates within the accommodation space 35. This ensures that the impact caused when the valve body 38 comes into contact with the valve seats 31a and 32a is mitigated by the crushing of the protrusions 39.

Because the valve body 38 is an elastic body, even if the protrusion 39 is pinched between the valve body 38 and the valve seats 31a, 32a when the switching valve 30 is closed, the valve body 38 can be easily brought into close contact with the valve seats 31a, 32a around the protrusion 39 due to the elastic deformation of the valve body 38. This makes it easier to seal between the valve body 38 and the protrusion 39 and the valve seats 31a, 32a.

Even after the valve body 38 comes into contact with the valve seats 31a, 32a due to a large liquid pressure difference, the projections 39 that protrude toward the opposite side of the valve seats 31a, 32a against which the valve body 38 is in contact, and the projections 39 in the flow paths 36, 37 are permitted to deform. These projections 39 deform due to the liquid flow in response to the liquid pressure difference between the first liquid chamber 17 and the second liquid chamber 18, thereby reducing the energy transmitted to the partition body 20 and improving the cushioning performance of the liquid-filled vibration isolation device 10.

Since multiple protrusions 39 extend radially from the spherical valve body 38 into the spherical storage space 35, the valve body 38 can be kept separated from the valve seats 31a, 32a with a simple configuration, even when the liquid pressure difference is small, similar to the stationary state described above. Furthermore, because the changeover valve 30 has such a simple configuration, the magnitude of the liquid pressure difference at which the valve body 38 abuts against the valve seats 31a, 32a can be easily adjusted according to the thickness D4, length L1, number, etc. of the protrusions 39. This makes it easier to design the changeover valve 30, including the opening and closing timing.

Although it depends on the hardness of the elastic body that constitutes the protrusion 39, by making the length L1 of the protrusion 39 at least twice the thickness D4 of the protrusion 39, the rigidity of the protrusion 39 can be adjusted so that the switching valve 30 closes during shake vibration and opens during idle vibration. This makes it possible to effectively exert the vibration-damping effect of the first orifice 19 tuned to match the shake vibration and the vibration-damping effect of the second orifice tuned to match the idle vibration.

The accommodation space 35 is spherical, the valve body 38 is spherical, and there are a total of six protrusions 39 on the X-axis, Y-axis, and Z-axis. When the tips of these protrusions 39 hit the wall surface of the accommodation space 35, the valve body 38 can be positioned at the center of the accommodation space 35 in a cross section perpendicular to the opposing direction of the openings 33 and 34. In particular, the length L1 of the protrusions 39 is set to be approximately the same as the difference between the diameter D1 of the valve body 38 and the diameter D2 of the accommodation space 35, so that the protrusions 39 on both sides of the valve body 38 hit the wall surface of the accommodation space 35, making it easier to maintain the state in which the valve body 38 is positioned at the center of the accommodation space 35. Furthermore, by making the length L1 of the protrusions 39 slightly larger than the difference between the diameter D1 of the valve body 38 and the diameter D2 of the accommodation space 35, the protrusions 39 are compressed in the length direction, making it easier to maintain the state in which the valve body 38 is positioned at the center of the accommodation space 35.

In this way, by positioning the valve body 38 in the center of the storage space 35, the valve body 38 moves in the opposing direction of the openings 33, 34, and the switching valve 30 opens and closes in response to the hydraulic pressure difference with almost no movement of the valve body 38 in the direction perpendicular to the opposing direction. Therefore, the timing at which the switching valve 30 opens and closes in response to the hydraulic pressure difference can be stabilized.

The accommodation space 35 that forms the switching valve 30 by accommodating the valve body 38 and the protrusion 39 is formed by the hemispherical dome portions 31, 32 that bulge out above and below the partition members 24, 25. This allows the dome portions 31, 32 (switching valve 30) to be surrounded by the first liquid chamber 17 and the second liquid chamber 18, respectively, making it possible to reduce the space required for the switching valve 30 in the liquid-filled vibration-proof device 10.

Although the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments, and it can be easily imagined that various improvements and modifications are possible within the scope of the present invention. The shapes and dimensions of each part, such as the first mounting fixture 11, the second mounting fixture 12, the vibration-isolating base 13, and the partition body 20, may be changed as appropriate. In addition, the formation positions and lengths of the first orifice 19 and the second orifice (the storage space 35 and the flow paths 36, 37) may be changed as appropriate. For example, the switching valve 30 and the second orifice may be provided on the axis C.

In the above embodiment, the liquid-filled vibration-damping device 10 is described as being used as an engine mount that elastically supports an automobile engine, but this is not necessarily limited to this. The liquid-filled vibration-damping device 10 may also be applied to various vibration-damping devices such as a body mount or a differential mount. In addition, the first mounting fixture 11 may be attached to the vehicle body side, and the second mounting fixture 12 may be attached to the vibration source side.

In the above embodiment, the storage space 35 is spherical, the valve body 38 is spherical, and multiple rod-shaped protrusions 39 extend radially; however, this is not necessarily limited to this. For example, the storage space 35 may be cylindrical, and the valve body 38 may be disk-shaped. Also, the opening and closing timing of the switching valve 30 according to the hydraulic pressure difference may be adjusted by vertically moving only the vicinity of the valve seats 31a, 32a away from or toward each other with respect to the spherical storage space 35 with a substantially constant diameter D2.

If the valve body 38 and the valve seats 31a, 32a can be separated by the protrusions 39 in the stationary state, the number and arrangement of the multiple protrusions 39 may be changed as appropriate depending on the shape of the valve body 38. The multiple protrusions 39 may be arranged in a spiral shape around the valve body 38, which is a sphere, or the multiple protrusions 39 may be arranged on a tangent to the surface of the valve body 38, which is a sphere. The rod-shaped protrusions 39 may be curved, or the protrusions 39 may be formed in a cone shape or a spiral shape.

In the above embodiment, the valve body 38 and the protrusion 39 are integrally formed from an elastic body, but this is not necessarily limited to this. The valve body 38 and the protrusion 39 may be formed from separate elastic bodies. The valve body 38 may also be formed from metal, synthetic resin, or the like.

REFERENCE SIGNS LIST 10 Liquid-filled vibration-proof device 11 First mounting fixture 12 Second mounting fixture 13 Vibration-proof base 15 Diaphragm 17 First liquid chamber 18 Second liquid chamber 19 First orifice 20 Partition body 30 Switching valve 33, 34 Opening 35 Storage space (part of second orifice)
36, 37 Flow path (part of second orifice)
38 Valve body 39 Protrusion

Claims (3)

A first attachment tool and a cylindrical second attachment tool;
a vibration-isolating base made of an elastic material that connects the first mounting fixture and the second mounting fixture;
a diaphragm made of an elastic material attached to the second mounting fixture and forming a liquid chamber filled with liquid between the diaphragm and the vibration-isolating base;
a partition body that divides the liquid chamber into a first liquid chamber and a second liquid chamber;
a first orifice and a second orifice respectively communicating the first liquid chamber and the second liquid chamber;
a switching valve that switches between a communication state and a blocking state of the second orifice,
The switching valve is
a spherical containing space having openings communicating with the first liquid chamber and the second liquid chamber, the spherical containing space forming a part of the second orifice;
a valve element that is a sphere having an inner diameter smaller than that of the accommodation space and that is movably accommodated in the accommodation space and that blocks the second orifice by abutting against a wall surface of the accommodation space around the opening;
a plurality of protrusions made of an elastic material and extending radially from the valve body;
A liquid-sealed vibration-damping device characterized in that, in a stationary state with no vibration input, the multiple protrusions separate the valve body from the wall surface of the storage space, placing the second orifice in a communicating state. The liquid-filled vibration-proof device according to claim 1, characterized in that the valve body is an elastic body integrally molded with the protrusion. the opening on the first fluid chamber side and the opening on the second fluid chamber side face each other on both sides of the valve body,
3. A liquid-filled vibration-damping device as described in claim 1 or 2, characterized in that a plurality of the protrusions are arranged on the valve body and abut against a wall surface of the storage space so that the valve body is positioned in the center of the storage space in a cross section perpendicular to the opposing direction between the opening on the first liquid chamber side and the opening on the second liquid chamber side.

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