JP6728599B2 - Anti-vibration device - Google Patents

Description

The present invention relates to a vibration damping device that mechanically connects a vibration generating unit and suppresses vibration transmitted from the vibration generating unit to a mounting unit.

In recent years, electric vehicles and hybrid vehicles have become widespread, and the quietness in the passenger compartment has improved compared to engine vehicles. When the vibration of the electric compressor is transmitted to the vehicle, noise in the vehicle interior increases. Therefore, it is required to further suppress the vibration transmission from the electric compressor to the vehicle. On the other hand, it is not preferable to complicate the structure for suppressing the transmission of vibrations, because it causes an increase in cost.

Therefore, in the mounting structure of the electric compressor described in Patent Document 1, a compressor-side bracket fixed to the lower portion of the electric compressor, a vehicle-side bracket fixed to the vehicle, and three elastic members arranged between them. And a member. Two of the three elastic members are arranged closer to the electric motor than the center of gravity of the electric compressor, and the other one is arranged closer to the compression mechanism than the center of gravity of the electric compressor.

JP, 2015-90130, A

In the mounting structure described in Patent Document 1 described above, since three elastic members support at three points, when a load is applied in the axial direction, the width direction, and the height direction of the compressor, the load is applied to each of the three points. Are not the same. For example, in axial displacement, two elastic members are arranged on one side in the axial direction and one elastic member is arranged on the other side in the axial direction, so that loads at three points are not the same. Since the loads are not the same, multiple resonance frequencies occur. There is a problem that a plurality of resonance frequencies generate a high frequency that causes noise.

Therefore, the present invention has been made in view of the above-mentioned problems, and an object thereof is to provide a vibration damping device capable of suppressing the vibration in a high frequency region by making the load acting on the elastic member evenly close to each other. To do.

The present invention adopts the following technical means in order to achieve the above object.

The present invention relates to a vibration isolator (31) for mechanically connecting a vibration generating section (24) and an installation target (27), which is integrally configured and is mechanically connected to the installation target. A member (32),
The four elastic members (33) include four elastic members between the support member and the vibration generating unit, which are mechanically connected to the supporting member and which suppress vibration of the vibration generating unit. They are disposed respectively on the four vertices in the rectangular virtual plane (36) (36a), each elastic member, a predetermined axis passing through the center as the mounting shaft (33b), a plane perpendicular to the mounting axis , suppression surface for receiving a load from vibration generating unit having a (33c), at a position opposing the suppressing surface of each elastic member, the center of gravity of the vibration generating portion are disposed right and left and a direction perpendicular in a virtual plane Direction and the front-back direction, and the direction orthogonal to the left-right direction and the front-back direction is the vertical direction,
As a coefficient, α is the angle with respect to the vertical direction of the mounting axis of the elastic member when viewed in the front-back direction of the vibration generating portion, and β is the vertical direction of the mounting axis of the elastic member when viewed in the horizontal direction of the vibration generating portion. Is the angle between the center of the suppression surface and the center of gravity of the vibration generating portion in the front-back direction, b is the distance between the center of the suppression surface and the center of gravity of the vibration generating portion in the left-right direction, and c is , The distance in the vertical direction between the center of the suppression surface and the center of gravity of the vibration generating portion, k1 is the rigidity in the direction perpendicular to the mounting axis of the elastic member when viewed in the front-rear direction, and k2 is when viewed in the left-right direction. The rigidity in the direction perpendicular to the mounting axis of the elastic member,
k3 is an anti-vibration device that satisfies the following equation, where k3 is the rigidity of the elastic member in the mounting axis direction .

According to the present invention as described above, the vibration generating unit is supported by the four elastic members. The four elastic members are respectively arranged at the four vertices of the rectangular virtual plane. The suppressing surface of the elastic member is arranged at a position facing the center of gravity of the vibration generating section. As a result, four elastic members are arranged so as to surround the center of gravity from four sides. When the direction in which one side of the virtual plane extends is the length direction and the direction orthogonal to the one side in the virtual plane is the width direction, the load in the length direction and the load in the width direction are evenly distributed to the four elastic members. Further, the load in the height direction perpendicular to the virtual plane is evenly distributed to the four elastic members. As a result, the resonance frequencies of the elastic members can be made the same, so that the vibration in the high frequency region can be suppressed.

In addition, the reference numerals in parentheses of the respective means described above are examples showing the correspondence with the specific means described in the embodiments described later.

It is a figure which shows the vehicle air conditioner 10 of 1st Embodiment. FIG. 3 is a perspective view showing a compressor 24 and a vibration isolation device 31. It is a side view showing a compressor 24 and a vibration isolation device 31. FIG. 3 is a plan view showing a compressor 24 and a vibration isolation device 31. It is a front view showing a compressor 24 and a vibration isolation device 31. FIG. 5 is a perspective view showing a support member 32. It is a side view which shows the support member 32. It is a top view which shows the support member 32. It is a front view which shows the support member 32. It is a perspective view showing a support piece 34. It is a side view which shows the support piece 34. It is a top view which shows the support piece 34. It is a front view which shows the support piece 34. It is a side view which shows the vibration isolator 31. 3 is a plan view showing a vibration isolation device 31. FIG. It is a front view showing the vibration isolator 31. FIG. 7 is a perspective view showing an elastic member 33. It is a figure which shows the calculation model of a YZ plane. It is a figure which shows the calculation model of an XZ plane. 6 is a graph showing a relationship between a rigidity ratio and a mounting position ratio. It is a graph which shows an analysis result. It is a perspective view which shows the other example of the elastic member 33.

(First embodiment)
The first embodiment of the present invention will be described with reference to FIGS. The vehicle air conditioner 10 is a so-called automatic air conditioner system configured to control an air conditioner unit 11 for air conditioning the interior of a vehicle by an air conditioner ECU in a vehicle such as an automobile equipped with an engine 27 for traveling. The air conditioning unit 11 is arranged inside the instrument panel at the forefront of the vehicle compartment, and accommodates the indoor blower 13, the evaporator 14, the heater core 15, and the like in an air conditioning case 12 that forms the outer shell thereof.

The air-conditioning case 12 has an air passage for blown air blown into the vehicle interior, and is formed of a resin such as polypropylene. An inside/outside air switching box 16 for switching and introducing inside air, which is the air inside the vehicle compartment, and outside air, which is the air outside the vehicle compartment, is arranged on the most upstream side of the blown air flow in the air conditioning case 12.

The inside/outside air switching box 16 is formed with an inside air inlet 17 for introducing inside air into the air conditioning case 12 and an outside air inlet 18 for introducing outside air. Further, in the inside/outside air switching box 16, an inside/outside air switching door for continuously adjusting the opening areas of the inside air inlet 17 and the outside air inlet 18 to change the air volume ratio of the air volume of the inside air to the air volume of the outside air. 19 are arranged.

The inside/outside air switching door 19 constitutes an air volume ratio changing means for switching the suction port mode for changing the air volume ratio between the air volume of the inside air introduced into the air conditioning case 12 and the air volume of the outside air. The inside/outside air switching door 19 is driven by an electric actuator for the inside/outside air switching door 19. The operation of the electric actuator for the inside/outside air switching door 19 is controlled by a control signal output from the air conditioner ECU.

An indoor blower 13 that blows air sucked through the inside/outside air switching box 16 toward the inside of the vehicle is disposed on the downstream side of the inside/outside air switching box 16 in the air flow direction. The indoor blower 13 is an electric blower that drives a centrifugal multi-blade fan with an electric motor, and its rotation speed is controlled by a control voltage output from an air conditioner ECU.

An evaporator 14 is arranged downstream of the indoor blower 13 in the air flow. The evaporator 14 is a cooling heat exchanger that cools the blown air by exchanging heat between the refrigerant flowing inside and the blown air. In the air conditioning case 12, on the downstream side of the air flow of the evaporator 14, air passages such as a hot air passage 20 and a cold air passage 21 through which air after passing through the evaporator 14 flows, and a hot air passage 20 and a cold air passage 21. A mixing space 22 is formed for mixing the air flowing out from the.

A heater core 15 is arranged in the warm air passage 20 as heating means for heating the air that has passed through the evaporator 14. The heater core 15 is a heating heat exchanger that heats the blast air by exchanging heat between the hot water flowing inside and the blast air. The warm water heated by the engine 27 flows into the heater core 15, and the flowing warm water exchanges heat with the air to heat the air. The heater core 15 functions as a mere flow path when the air mix door 23 is in an open/close state in which air does not pass through the heater core 15.

The cold air passage 21 is an air passage for guiding the air that has passed through the evaporator 14 to the mixing space 22 without passing through the heater core 15. Therefore, the temperature of the blown air mixed in the mixing space 22 changes depending on the air volume ratio of the air passing through the warm air passage 20 and the air passing through the cold air passage 21.

In the present embodiment, on the downstream side of the air flow of the evaporator 14 and on the inlet side of the hot air passage 20 and the cold air passage 21, the air flow rate of the cold air to be introduced into the hot air passage 20 and the cold air passage 21 is continuously provided. An air mix door 23 to be changed is arranged. Therefore, the air mix door 23 constitutes a temperature adjusting means for adjusting the air temperature in the mixing space 22. The air mix door 23 is driven by an electric actuator for the air mix door 23. The operation of the electric actuator for the air mix door 23 is controlled by a control signal output from the air conditioner ECU.

The evaporator 14 constitutes a refrigeration cycle together with the compressor 24, the condenser 25, the expansion valve 26, the accumulator 28, and the like. The compressor 24 is arranged in the engine room and sucks, compresses and discharges the refrigerant in the refrigeration cycle. The compressor 24 is driven by an engine 27 mounted in the engine room of the vehicle, sucks the refrigerant, compresses it, and discharges it.

The condenser 25 is arranged in the engine room, and heat-exchanges the refrigerant flowing inside with the outside air to condense and liquefy the compressed refrigerant. The accumulator 28 separates the gas-liquid two-phase refrigerant from the condenser 25 into a liquid refrigerant and a gas refrigerant. The expansion valve 26 is a decompression unit that decompresses and expands the liquid refrigerant separated by the accumulator 28. The evaporator 14 evaporates the refrigerant that has been decompressed and expanded by heat exchange between the refrigerant and the blown air.

The flow of the refrigerant during the cooling cycle operation will be described. In the cooling cycle, the compressor 24, the condenser 25, the accumulator 28, the expansion valve 26, and the evaporator 14 flow in this order and then return to the compressor 24 again. By the pipe through which the refrigerant flows in this way, the components of the refrigeration cycle are formed in an annular connection. The compressor 24 draws in and discharges the refrigerant. The refrigerant discharged from the compressor 24 reaches the condenser 25. At this time, the opening degree of the air mix door 23 is controlled so that the air does not pass through the heater core 15.

The refrigerant discharged from the compressor 24 flows into the condenser 25, and the flowing-in refrigerant exchanges heat with air to radiate heat. The refrigerant flowing out of the condenser 25 is gas-liquid separated by the accumulator 28. The liquid refrigerant separated by the accumulator 28 is decompressed and cooled by the expansion valve 26. The refrigerant decompressed by the expansion valve 26 flows into the evaporator 14 and evaporates to cool the blown air. Then, the refrigerant having passed through the evaporator 14 is sucked into the compressor 24.

As shown in FIGS. 1 and 2, the compressor 24 is mounted on the engine 27 via a vibration isolation device 31. The engine 27 is mounted in the engine room that is the installation target. The vibration isolator 31 is mechanically connected to the engine 27 by three mounting bolts 30, as shown in FIGS. 3 and 4.

Therefore, the vibration of the compressor 24 is transmitted to the engine 27 as indicated by an arrow in FIG. 1, and the sound generated by the vibration of the compressor 24 is emitted from the engine 27 to the outside of the vehicle. When the engine 27 is driven, the vibration of the engine 27 and the driving sound of the engine 27 are radiated to the outside, so that the noise caused by the compressor 24 is not noticeable to the driver. However, when the engine sound is low, such as when the engine 27 is stopped or idle, the vehicle exterior noise caused by the vibration transmitted from the compressor 24 to the engine 27 becomes a problem.

Therefore, in the present embodiment, the vibration of the compressor 24 is suppressed by the vibration damping device 31, and the vibration of the compressor 24 is suppressed from being transmitted to the engine 27. The vibration isolator 31 includes a support member 32, four elastic members 33, and four support pieces 34. The compressor 24 has a cylindrical shape and extends in the front-rear direction X. Of the directions orthogonal to the front-rear direction X, the vertical direction is referred to as the vertical direction Z. A direction orthogonal to the front-rear direction X and the up-down direction Z is referred to as a left-right direction Y.

As shown in FIGS. 6 and 7, the support member 32 has a substantially L-shaped cross section when viewed in the front-rear direction X. The support member 32 includes a wall portion 32a that extends in the up-down direction Z and the front-rear direction X and faces the engine 27, and a bottom portion 32b that extends in the front-rear direction X and the left-right direction Y and supports the compressor 24. As shown in FIGS. 6 and 9, the wall portion 32a is formed with three insertion holes 32c. When the support member 32 is attached to the engine 27, the mounting bolt 30 is inserted into the insertion hole 32c as shown in FIGS. 3 and 4, and the male screw of the mounting bolt 30 is inserted into the female screw formed on the engine 27. Screw together. As a result, the support member 32 is fixed to the engine 27.

As shown in FIGS. 6 and 8, the bottom portion 32b is provided with four slope portions 35 having slopes on the upper side in the vertical direction Z. A through hole 35 a is formed in the center of the slope portion 35. The four slope portions 35 are arranged at the four apexes 36 a of the rectangular virtual plane 36 when viewed in the vertical direction Z. The direction in which one side of the virtual plane 36 extends is the front-back direction X. The direction orthogonal to one side on the virtual plane 36 is the left-right direction Y.

As for the positional relationship between the four sloped portions 35, the through holes 35a of the sloped portion 35 are arranged at the four vertices 36a of a rectangular virtual plane 36 when viewed in the vertical direction Z, as shown in FIG. Further, the normal lines of the four slope portions 35 extend obliquely upward as indicated by a virtual line 37 in FIGS. 7 and 9. Therefore, as shown in FIG. 8, the diagonal surface portions 35 facing each other face each other so that the diagonal surface extends upward.

The support member 32 is formed by fastening two members with a bolt 32d. As shown in FIG. 7 and FIG. 8, it is possible to separate in the left-right direction Y by a cutting plane including the up-down direction Z and the front-back direction X. Both ends in the front-rear direction X are fixed by bolts 32d extending in the left-right direction Y.

As shown in FIG. 17, the elastic member 33 has a columnar shape having a through hole 33a. The elastic member 33 has elasticity and is, for example, rubber. The elastic member 33 has a columnar axis serving as a predetermined mounting axis 33b. A surface that intersects with the mounting shaft 33b serves as a suppression surface 33c that receives the load from the compressor 24. The suppression surface 33c is a plane perpendicular to the mounting shaft 33b in the present embodiment. Here, “vertical” is not limited to 90 degrees, but may be 85 degrees or more and 95 degrees or less. In other words, the suppressing surface 33c intersects the mounting shaft 33b at an angle of 85 degrees or more and 95 degrees or less. In the present embodiment, the surface of the elastic member 33 on the compressor 24 side in the axial direction serves as the suppression surface 33c. The four elastic members 33 are arranged at the four apexes 36a of the rectangular virtual plane 36, respectively. The four vertices 36 a may be arranged at least inside the elastic member 33 when viewed in the vertical direction Z. When the four elastic members 33 are viewed in the vertical direction Z, it is preferable that the shape connecting the centers of the elastic members 33 be a rectangle. Further, when the four elastic members 33 are viewed in the front-rear direction X and the left-right direction Y, the centers of the respective elastic members 33 are aligned. Further, the center of the virtual plane 36 is preferably arranged so as to overlap with the vertical axis passing through the center of gravity 24 a of the compressor 24 when viewed in the vertical direction Z.

As shown in FIGS. 10, 11 and 12, the support piece 34 includes an inclined portion 38 having a through hole 38a and a mounting portion 39 having a through hole 39a. The inclined portion 38 has the same inclination angle as the inclined surface portion 35, and is attached to the inclined surface portion 35 via the elastic member 33 as shown in FIGS. 14 and 16. As shown in FIG. 13, the mounting portion 39 has a through hole 39a extending in the left-right direction Y.

As shown in FIG. 5, the support piece 34 is provided between the elastic member 33 and the compressor 24, and is mechanically connected to the compressor 24 by a bolt 24b. As shown in FIG. 15, the bolts 24b are inserted so as to connect the mounting portions 39 facing each other in the left-right direction Y. The bolt 24b inserted through the attachment portion 39 is inserted through an attachment hole (not shown) formed in the compressor 24. The mounting hole of the compressor 24 extends in the left-right direction Y. In other words, in the lower part of the compressor 24, two mounting holes into which the bolts are inserted in the left-right direction Y are provided at intervals in the front-rear direction X.

Further, the support pieces 34 are mechanically connected to the sloped portions 35 by bolts 34a. The elastic member 33 shown in FIG. 17 is sandwiched between the slope portion 35 and the support piece 34. Then, a bolt 34a is provided so as to pass through the through hole 35a of the inclined surface portion 35, the through hole 33a of the elastic member 33, and the through hole 38a of the inclined portion 38, and is fastened by the nut 34b. This mechanically connects the support member 32, the elastic member 33, and the support piece 34.

Since the elastic member 33 is arranged so as to be sandwiched between the inclined surface portion 35 and the inclined portion 38 of the support piece 34, the suppressing surface 33c of the elastic member 33 faces the center of gravity 24a of the compressor 24. Specifically, the center of gravity 24 a of the compressor 24 is arranged at a position facing the restraining surface 33 c of each elastic member 33. The fact that the center of gravity 24a is located at a position where the restraining surface 33c is opposed means that the center of gravity 24a is located in a region radially extending from the restraining surface 33c in the direction in which the mounting shaft 33b extends. And, preferably, the center of gravity 24a being located at a position where the suppressing surface 33c is opposed means that the center of gravity 24a is located within a projection area projected in a direction in which the mounting shaft 33b extends from the suppressing surface 33c.

Next, the positional relationship of the elastic member 33 for suppressing the coupling of the rotational vibration and the translational vibration will be described with reference to FIGS. 18 and 19. 18 and 19 show models for calculating the suppression of rotational vibration and translational vibration. In the calculation model, as shown in FIG. 18, when viewed in the front-rear direction X, the mounting shaft 33b of the elastic member 33 is inclined at an angle α with respect to the vertical direction Z. The elastic member 33 is in contact with the compressor 24 at a position separated from the center of gravity 24a of the compressor 24 in the vertical direction Z by a height c. The elastic member 33 is in contact with the center of gravity 24a of the compressor 24 at a position separated from the center of gravity 24a of the compressor 24 by the width b in the left-right direction Y. The diameter of the compressor 24 is D.

Further, in the calculation model, as shown in FIG. 19, when viewed in the left-right direction Y, the mounting shaft 33b of the elastic member 33 is inclined at an angle β with respect to the vertical direction Z. Further, the elastic member 33 is in contact with a position separated from the center of gravity 24a of the compressor 24 in the front-rear direction X by a length a.

In the calculation model, the radial rigidity of the elastic member 33 when viewed in the front-rear direction X is indicated by k1, and the radial rigidity when viewed in the left-right direction Y is indicated by k2. The rigidity of the elastic member 33 in the mounting shaft 33b direction is indicated by k3.

First, the equation of motion on the YZ plane of FIG. 18 will be described. The equation of motion for translation is shown in equation (1), and the equation of motion for rotation is shown in equation (2). In Expression (1), the coupling term is the third term on the left side. In the formula (2), the coupling term is also the third term on the left side.

The coefficient K _{24 of the} coupling term is given by the equation (3). If the coupling term is 0, there is no coupling, that is, so-called non-coupling. Therefore, if the coefficient K ₂₄ of the coupling term becomes 0, the coupling term also becomes 0, and the coupling is not coupled.

In Expression (3), the subscript i is assigned to the four elastic members 33. Therefore, i is an integer of 1 to 4. The coefficient K _22i and the coefficient K _23i in Expression (3) can be expressed by Expression (4) and Expression (5).

Here, the stiffness k of each elastic member 33 is set to the same value as shown in Expressions (6) to (8).

Similarly, the position of each elastic member 33 is set to the same value as shown in Expressions (9) to (12).

Then, the coefficient K _22i and the coefficient K _23i also have the same value as shown in Expressions (13) and (14).

The condition for substituting the equations (13) and (14) into the equation (3) and setting the coefficient K ₂₄ to 0 can be expressed by the equation (15).

Substituting equation (4), equation (5), equation (13), and equation (14) into equation (15) yields equation (16).

Similarly, regarding the equation of motion on the XZ plane of FIG. 19, the condition that the coefficient K ₂₄ for suppressing coupling is 0 in equation (11) is that b is a, k2 is k1, and α is β. It can be replaced and can be expressed by equation (17).

In order to make the rigidity and the resonance frequency in all translational directions in the front-rear direction X, the left-right direction Y, and the up-down direction Z the same, α=β=45 deg. Further, as shown in FIG. 17, when the elastic member 33 is a cylindrical type, the rigidity is k1=k2 in the case of the elastic member 33. The elastic member 33 is not limited to the cylindrical shape, and may be a square shape having a through hole 33a as shown in FIG. Even with such a square shape, the rigidity is k1=k2. Therefore, if a=b, the rigidity ratios k ₁ /k ₃ and the rigidity ratios k ₂ /k ₃ that can satisfy both Expression (16) and Expression (17) can be determined.

FIG. 20 shows the relationship between the mounting position ratio and the rigidity ratio when the expressions (16) and (17) are satisfied. Therefore, by selecting the mounting position and the elastic member 33 so that the ratio satisfies the relationship shown in FIG. 20, the coupling is not performed on the XZ plane and the YZ plane.

In the present embodiment, the elastic member 33 is installed so that the rigidity ratio and the mounting position ratio shown in FIG. Further, in the YZ plane, b<D is preferable because the elastic member 33 is installed on the support member 32. In other words, the dimension of the compressor 24 in the left-right direction Y is preferably larger than the dimension of the virtual plane 36 in the left-right direction Y.

Further, since the general compressor 24 has an outer diameter D<a length L in the front-rear direction X as shown in FIG. 4, if a=b as described above, a<L. Therefore, the position a of the elastic member 33 in the front-rear direction X is closer to the center of gravity 24a than the end portion of the support member 32 in the front-rear direction X. In other words, the dimension of the compressor 24 in the front-rear direction X is larger than the dimension of the virtual plane 36 in the front-rear direction X. This makes it easier to mount the elastic member 33 in the front-back direction X than when the elastic member 33 is arranged outside the compressor 24.

Next, the effect of this embodiment will be described with reference to FIG. In FIG. 21, the waveform of the example in which the vibration damping device 31 of the present embodiment is mounted, the waveform of the comparative example 1, and the waveform of the comparative example 2 are drawn. The vertical axis of FIG. 21 represents the transmission load transmitted from the compressor 24 to the engine 27, and the horizontal axis represents the frequency. The target is a transmission load of 0.1 N or less in a high frequency region, for example, a region where the frequency is 500 Hz or higher.

Comparative Example 1 has a configuration in which the elastic member 33 is provided between the support member 32 and the engine 27. Specifically, in Comparative Example 1, when the support member 32 and the engine 27 are attached to the attachment bolt 30, the elastic member 33 is provided on the outer periphery of the attachment bolt 30. Therefore, in Comparative Example 1, the elastic member 33 is not provided between the compressor 24 and the support member 32. Comparative Example 2 has a configuration in which the four elastic members 33 are removed from the present embodiment. In other words, the elastic member 33 is removed from between the engine 27 and the support member 32 in the first comparative example.

As shown in FIG. 21, in Comparative Example 2, since the elastic member 33 is not used, the resonance frequency is generated in the high frequency region and exceeds the target in the entire high frequency region. In Comparative Example 1, although the elastic member 33 is able to reduce the amount to some extent, since they are coupled, a plurality of resonance frequencies occur and the transmission load cannot be reduced at 500 Hz.

On the other hand, in the embodiment, since the coupling is not performed, the resonance frequency can be gathered around 300 Hz. This can reduce the load of 500 Hz or more. Therefore, transmission of high-frequency vibrations to the engine 27 can be suppressed.

As described above, the vibration damping device 31 of the present embodiment supports the compressor 24 by the four elastic members 33. The four elastic members 33 are arranged at the four apexes 36a of the virtual virtual plane 36 having a rectangular shape. The restraining surface 33c of the elastic member 33 is arranged at a position facing the center of gravity 24a of the compressor 24. As a result, the four elastic members 33 are arranged so as to surround the center of gravity 24a from all sides. Therefore, the load in the longitudinal direction X, which is the length direction, and the load in the lateral direction Y, which is the width direction, are evenly distributed to the four elastic members 33. Further, the load in the vertical direction Z, which is the height direction perpendicular to the virtual plane 36, is evenly distributed to the four elastic members 33. As a result, the resonance frequencies of the elastic members 33 can be made equal to each other, so that vibration in the high frequency region can be suppressed.

In other words, when a load is applied in the front-rear direction X, the left-right direction Y, and the up-down direction Z, the load received by the elastic member 33 can be the same, so that the generation of a plurality of resonance frequencies is suppressed and the high frequency vibration is suppressed. can do.

Further, in the present embodiment, the distances from the centers of the respective restraining surfaces 33c to the center of gravity 24a of the compressor 24 are equal to each other. This facilitates the determination of the rigidity ratio that can satisfy both the above equation (16) and equation (17). Therefore, since it is easy to realize the configuration that suppresses the occurrence of resonance due to the coupling of rotation and translation, it is possible to further suppress the vibration in the high frequency region.

Further, in the present embodiment, the vibration isolator 31 includes four support pieces 34. The support piece 34 is provided between the elastic member 33 and the compressor 24, and is mechanically connected to the compressor 24. By providing the support piece 34, the assembling property can be improved.

Further, in the present embodiment, the dimension of the compressor 24 in the left-right direction Y is larger than the dimension of the virtual plane 36 in the left-right direction Y. The dimension of the virtual plane 36 in the left-right direction Y is the distance between the elastic members 33 in the left-right direction Y, as shown in FIG. Thereby, as shown in FIG. 4, the elastic member 33 can be arranged so as to be hidden under the compressor 24. Therefore, the vibration isolator 31 can be downsized.

Further, in the present embodiment, the dimension of the compressor 24 in the front-rear direction X is larger than the dimension of the virtual plane 36 in the front-rear direction X. The dimension of the virtual plane 36 in the front-rear direction X is the distance between the elastic members 33 in the front-rear direction X, as shown in FIG. Thereby, as shown in FIG. 5, the elastic member 33 can be arranged inside the compressor 24. Therefore, the vibration isolator 31 can be downsized.

(Other embodiments)
Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and can be variously modified and implemented without departing from the gist of the present invention.

The structures of the above embodiments are merely examples, and the scope of the present invention is not limited to the scope of these descriptions. The scope of the present invention is shown by the description of the claims, and includes the meaning equivalent to the description of the claims and all modifications within the scope.

In the above-described first embodiment, the installation object on which the compressor 24 is installed is the engine 27, but the installation object is not limited to the engine 27. For example, it may be another vibration generating unit of the engine 27. Further, the installation target may be a portion to which vibration from the vibration source is transmitted, instead of the vibration source. Nor is it limited to vehicles.

Although the support piece 34 is included in the first embodiment, the support piece 34 may not be included. For example, the compressor 24 may have a foot corresponding to the support piece 34 in advance, and the foot and the elastic member 33 may be mechanically connected to each other.

In the above-described first embodiment, the distances from the centers of the respective restraining surfaces 33c to the center of gravity 24a of the compressor 24 are equal to each other, but are not limited to being strictly equal. Even if the distance from the center of each restraint surface 33c to the center of gravity 24a of the compressor 24 is strictly different, it may be considered as equal if the difference in the distance from each restraint surface 33c to the center of gravity 24a is within 5%. ..

X... longitudinal direction Y... lateral direction Z... vertical direction 10... vehicle air conditioner 24... compressor 24a... center of gravity 25... condenser 26... expansion valve 27... engine 28... accumulator 30... mounting bolt 31... anti-vibration device 32... Support member 32a... Wall portion 32b... Bottom portion 33... Elastic member 33b... Mounting shaft 33c... Suppression surface 34... Support piece 35... Slope surface portion 36... Virtual plane 36a... Apex 37... Virtual line 38... Inclined portion 39... Mounting portion

Claims (5)

A vibration isolation device (31) for mechanically connecting a vibration generator (24) and an installation target (27),
A support member (32) configured integrally and mechanically connected to the installation target;
Between the support member and the vibration generating unit, four elastic members that are provided to be mechanically connected to the support member and suppress the vibration of the vibration generating unit,
The four elastic members (33) are respectively arranged at the four vertices (36a) in the rectangular virtual plane (36),
Wherein each of the elastic member, a predetermined axis passing through the center as the mounting shaft (33b), a plane perpendicular to the mounting shaft has an inhibitory surface (33c) which receives the load from the vibration generating portion,
The center of gravity of the vibration generating unit is arranged at a position facing the suppressing surface of each elastic member,
A direction orthogonal to the virtual plane is a left-right direction and a front-rear direction, a direction orthogonal to the left-right direction and the front-rear direction is an up-down direction,
As a coefficient,
α is an angle of the mounting shaft of the elastic member with respect to the vertical direction when viewed in the front-rear direction of the vibration generating unit,
β is an angle formed by the mounting shaft of the elastic member and the vertical direction when viewed in the horizontal direction of the vibration generating unit,
a is a distance between the center of the suppression surface and the center of gravity of the vibration generating unit in the front-rear direction,
b is the distance in the left-right direction between the center of the suppression surface and the center of gravity of the vibration generating section,
c is the vertical distance between the center of the suppression surface and the center of gravity of the vibration generating section,
k1 is the rigidity of the elastic member in the direction perpendicular to the mounting shaft when viewed in the front-rear direction,
k2 is the rigidity of the elastic member in the direction perpendicular to the mounting shaft when viewed in the left-right direction,
When k3 is the rigidity of the elastic member in the mounting axis direction,
An anti-vibration device satisfying the following formula .

The vibration isolator according to claim 1, wherein the distances from the centers of the respective suppression surfaces to the center of gravity of the vibration generating unit are equal to each other. The vibration isolator according to claim 1 or 2, further comprising four support pieces provided between the elastic member and the vibration generating unit and mechanically connected to the vibration generating unit. A length direction is a direction in which one side of the virtual plane extends, and a width direction is a direction orthogonal to the one side in the virtual plane,
The anti-vibration device according to any one of claims 1 to 3, wherein a dimension of the vibration generating unit in the width direction is larger than a dimension of the virtual plane in the width direction. A length direction is a direction in which one side of the virtual plane extends, and a width direction is a direction orthogonal to the one side in the virtual plane,
The vibration isolator according to any one of claims 1 to 4, wherein a dimension of the vibration generating unit in the length direction is larger than a dimension of the virtual plane in the length direction.

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