Support structure for electric compressor

Abstract

To provide a new support structure for an electric compressor capable of reducing vibration transmission from the scroll type electric compressor to a vehicle body side member.SOLUTION: A support structure 10 for an electric compressor 12 supports the electric compressor on a vehicle body side member 40 in a vibration proof manner by using vibration damping devices 24a, 24b. The electric compressor 12 has a structure in which an electric motor 14 and a compression mechanism part 16 are disposed in series in an extending direction of an output shaft 20 of the electric motor 14 and accommodated in a case 18. The first vibration damping device 24a is disposed on each of both sides of the case 18 in an extending direction of a torque pitch axis A, and the second vibration damping device 24b is disposed on each of both sides of the case 18 in an extending direction of a torque yaw axis B. The first vibration damping device 24a is disposed within a region in which an inclination angle θ1 to the torque pitch axis A is ±20 degrees, and the second vibration damping device 24b is disposed in a region in which an inclination angle θ2 to the torque yaw axis B is ±20 degrees.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a support structure for an electric compressor in which an electric compressor is supported on a vehicle body member in a vibration-isolating manner by a vibration-isolating device. [Background technology]

[0002] Conventionally, vehicles such as automobiles have been provided with electric compressors that constitute refrigeration units of air conditioners, etc. The electric compressors are attached to vehicle body side members, as disclosed in, for example, Japanese Patent Laid-Open Publication No. 2016-138495 (Patent Document 1).

[0003] There are several types of electric compressors known, each with a different compression method, such as reciprocating and screw types. However, the adoption of a scroll type, as shown in Patent Document 1, is being considered for use in vehicles such as automobiles. A scroll compressor pressurizes gas between a pair of scrolls, each having a spiral wall inserted between them, by changing the volume between the spiral walls of the scrolls as the scrolls rotate relative to each other. In an electric compressor, for example, one scroll is fixed so as not to rotate, and the other scroll is rotated by an electric motor. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-138495 Summary of the Invention [Problem to be solved by the invention]

[0005] In a scroll-type electric compressor, eccentric rotation of the scroll, which is the compression mechanism, generates vibrations during operation, and it is necessary to prevent the vibrations from being transmitted to the vehicle body member, which is the member to be isolated from vibrations. Therefore, the electric compressor is connected to the vehicle body member in a vibration-isolating manner via a vibration-isolating device. For example, in Patent Document 1, multiple elastic members are arranged between the electric compressor and the vehicle body member, and the vibration-isolating effect of the elastic members suppresses the transmission of vibrations from the electric compressor to the vehicle body member.

[0006] However, in Patent Document 1, the electric compressor is located above the vehicle body side members, and only multiple elastic members are interposed between the electric compressor and the vehicle body side members, making it difficult to sufficiently suppress the transmission of vibration from the electric compressor to the vehicle body side members.

[0007] In particular, in Patent Document 1, the electric compressor is elastically supported in a cantilevered manner above the vehicle body member by multiple elastic members arranged below the electric compressor, which may amplify vibrations of the electric compressor in a specific frequency range, significantly worsening the state of vibration transmission to the vehicle body member.

[0008] An object of the present invention is to provide a novel support structure for an electric compressor that can more effectively reduce the transmission of vibration from a scroll-type electric compressor to a vehicle body member. [Means for solving the problem]

[0009] The following describes preferred embodiments for understanding the present invention, but the embodiments described below are merely examples and may be appropriately combined with one another. Multiple components described in each embodiment may be recognized and employed independently to the greatest extent possible, and may also be appropriately combined with any of the components described in other embodiments. Accordingly, the present invention is not limited to the embodiments described below, and various other embodiments may be realized.

[0010] The first aspect is a support structure for an electric compressor that supports the electric compressor on a vehicle body side member in a vibration-damping manner using a vibration-damping device. The electric compressor has a scroll-type compression mechanism that is rotated by an electric motor. The electric motor and compression mechanism are arranged in series in the output shaft direction, which is the direction in which the output shaft of the electric motor extends, and are housed in a case. The vibration-damping device includes a first vibration-damping device and a second vibration-damping device. The first vibration-damping devices are arranged on both sides of the case in the extension direction of a torque pitch axis that intersects the output shaft direction of the electric motor, and the second vibration-damping devices are arranged on both sides of the case in the extension direction of a torque yaw axis that intersects the output shaft direction of the electric motor and the torque pitch axis. The first vibration-damping device is arranged within a range of inclination angle of ±20 degrees with respect to the torque pitch axis, and the second vibration-damping device is arranged within a range of inclination angle of ±20 degrees with respect to the torque yaw axis.

[0011] Through investigation and experimentation, the inventors have found that the vibrations exerted by the electric compressor on the vehicle body members due to the eccentric rotation of the scroll are mainly caused by moments around two torque axes (torque pitch axis and torque yaw axis) other than the torque roll axis extending in the direction of the output shaft of the electric motor. Based on this finding, the inventors have invented a support structure for an electric compressor that is capable of suppressing the transmission of vibrations to the vehicle body members.

[0012] In other words, with the support structure for an electric compressor constructed according to this aspect, the first vibration isolating device is disposed near the torque pitch axis, thereby reducing transmission of vibrations caused by the moment about the torque pitch axis generated by rotation of the eccentric mass of the compression mechanism from the electric compressor to the vehicle body member via the first vibration isolating device. Furthermore, because the second vibration isolating devices are disposed on both sides of the center of gravity of the electric compressor, forces caused by the moment about the torque pitch axis acting on the second vibration isolating devices on both sides act in opposite directions on the vehicle body member, thereby canceling out each other. In this way, transmission of vibrations caused by the moment about the torque pitch axis to the vehicle body member is suppressed.

[0013] In addition, because the second vibration isolation device is located near the torque yaw axis, transmission of vibrations caused by the moment about the torque yaw axis, which is generated when the compression mechanism rotates as an eccentric mass, from the electric compressor to the vehicle body member via the second vibration isolation device is reduced. Furthermore, because the first vibration isolation devices are located on both sides of the center of gravity of the electric compressor, forces caused by the moment about the torque yaw axis acting on the first vibration isolation devices on both sides act in opposite directions on the vehicle body member, thereby canceling out. In this way, transmission of vibrations caused by the moment about the torque yaw axis to the vehicle body member is suppressed.

[0014] As described above, in the support structure for an electric compressor according to this aspect, the vibration isolators are positioned relative to the torque pitch axis and torque yaw axis based on the novel idea that input due to eccentric rotation of the compression mechanism generated in a scroll-type electric compressor is transmitted to vehicle body components as vibration loads resulting from moments about the torque pitch axis and torque yaw axis of the electric compressor, thereby realizing a support structure for an electric compressor that can effectively suppress the transmission of vibration from the electric compressor to vehicle body components.

[0015] A second aspect is a support structure for an electric compressor described in the first aspect, in which at least a portion of each of the first vibration isolation devices is located on the torque pitch axis, and at least a portion of each of the second vibration isolation devices is located on the torque yaw axis.

[0016] In the support structure for an electric compressor constructed according to this aspect, the first vibration isolation device is disposed closer to the torque pitch axis so that at least a portion of the first vibration isolation device is located on the torque pitch axis, thereby further reducing the transmission of vibrations caused by moments about the torque pitch axis via the first vibration isolation device. Also, the second vibration isolation device is disposed closer to the torque yaw axis so that at least a portion of the second vibration isolation device is located on the torque yaw axis, thereby further reducing the transmission of vibrations caused by moments about the torque yaw axis via the second vibration isolation device.

[0017] In a third aspect, in the support structure for an electric compressor described in the first or second aspect, one first vibration isolation device is arranged on each side of the electric compressor in the extension direction of the torque pitch axis relative to the case, and one second vibration isolation device is arranged on each side of the electric compressor in the extension direction of the torque yaw axis relative to the case.

[0018] According to the support structure for an electric compressor constructed in accordance with this aspect, the electric compressor can be supported on a vehicle body member with a small number of vibration-isolating devices. Furthermore, since the number of first vibration-isolating devices and second vibration-isolating devices is small, it is easier to arrange the first vibration-isolating devices and second vibration-isolating devices in appropriate positions.

[0019] A fourth aspect is a support structure for an electric compressor described in any one of the first to third aspects, wherein the first vibration-damping device and the second vibration-damping device are cylindrical vibration-damping devices in which an inner shaft member and an outer cylindrical member are connected by a main rubber elastic body, and the axial direction of the inner shaft member of the first vibration-damping device attached to the case of the electric compressor is the extension direction of the torque pitch axis, and the axial direction of the inner shaft member of the second vibration-damping device attached to the case of the electric compressor is the extension direction of the torque yaw axis.

[0020] In the support structure for an electric compressor constructed according to this aspect, the first vibration-damping device is a cylindrical vibration-damping device with its axial direction extending in the direction of the torque pitch axis, thereby reducing torsional rigidity when a moment about the torque pitch axis acts. Therefore, the low torsional rigidity of the first vibration-damping device makes it possible to set the resonant frequency of the support structure for the electric compressor to a lower frequency. Similarly, the second vibration-damping device is a cylindrical vibration-damping device with its axial direction extending in the direction of the torque yaw axis, thereby reducing torsional rigidity when a moment about the torque yaw axis acts. Therefore, the low torsional rigidity of the second vibration-damping device makes it possible to set the resonant frequency of the support structure for the electric compressor to a lower frequency.

[0021] A fifth aspect is a support structure for an electric compressor described in any one of the first to fourth aspects, wherein the difference between the distance from the first vibration-damping device arranged on one side of the case to the center of gravity of the electric compressor and the distance from the first vibration-damping device arranged on the other side of the case to the center of gravity of the electric compressor is 20% or less of either shorter distance, and the difference between the distance from the second vibration-damping device arranged on one side of the case to the center of gravity of the electric compressor and the distance from the second vibration-damping device arranged on the other side of the case to the center of gravity of the electric compressor is 20% or less of either shorter distance.

[0022] In the support structure for an electric compressor constructed according to this aspect, the difference in distance between the first vibration isolation devices on both sides of the case and the center of gravity of the electric compressor is reduced, which further reduces the difference in vibration loads acting on the first vibration isolation devices on both sides of the case due to the moment about the torque yaw axis. As a result, the vibration loads transmitted to the vehicle body components via the first vibration isolation devices on both sides of the case are more effectively canceled out, and the transmission of vibrations to the vehicle body components is suppressed.

[0023] Similarly, by reducing the difference in distance between the second vibration isolation devices on both sides of the case and the center of gravity of the electric compressor, the difference in vibration loads acting on the second vibration isolation devices on both sides of the case due to the moment about the torque pitch axis is reduced, so that the vibration loads transmitted to the vehicle body components via the second vibration isolation devices on both sides of the case are more effectively canceled out, and the transmission of vibrations to the vehicle body components is suppressed. [Effects of the Invention]

[0024] According to the present invention, in a support structure for an electric compressor, it is possible to reduce the transmission of vibration from a scroll-type electric compressor to a vehicle body side member. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is a plan view showing a support structure for an electric compressor according to a first embodiment of the present invention; [Figure 2] Front view of the support structure for the electric compressor shown in Figure 1 [Figure 3] Left side view of the support structure for the electric compressor shown in Figure 1 [Figure 4] A perspective view of a rubber mount that constitutes the support structure of the electric compressor shown in Figure 1. [Figure 5] Cross section of the rubber mount shown in Figure 1 [Figure 6] A diagram showing a model of the support structure of the electric compressor shown in Figure 1. [Figure 7] Graph of the force transmitted from the electric compressor to the vehicle body component [Figure 8] 1 is a plan view showing a support structure for a conventional electric compressor. [Figure 9] FIG. 9 is a front view of the support structure for the electric compressor shown in FIG. [Figure 10] Left side view of the support structure for the electric compressor shown in Figure 8 DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0027] 1 to 3 show a support structure 10 for an electric compressor according to a first embodiment of the present invention. The support structure 10 for an electric compressor includes an electric compressor 12. In the following description, in principle, the up-down direction refers to the up-down direction in FIG. 2 which corresponds to the up-down direction of the vehicle, the front-rear direction refers to the up-down direction in FIG. 1 which corresponds to the front-rear direction of the vehicle, and the left-right direction refers to the left-right direction in FIG. 1 which corresponds to the left-right direction of the vehicle.

[0028] The electric compressor 12 is a scroll-type electric compressor, with an electric motor 14 and a scroll member 16 serving as a compression mechanism housed in a hollow case 18. The electric motor 14 is, for example, an AC brushless motor. The electric motor 14 outputs rotational force when an output shaft 20 is rotated by an external power supply. The electric motor 14 is housed in a housing body 22 of the case 18. The housing body 22, which houses the electric motor 14, is a cylindrical portion that surrounds the outer periphery of the electric motor 14 and extends continuously around the entire circumference with a smooth surface. The housing body 22 does not include any locally protruding portions formed on the periphery, such as ribs for attaching accessories or reinforcing ribs.

[0029] The scroll member 16 includes a fixed scroll fixedly positioned relative to the case 18 and an orbiting scroll attached to the output shaft 20 of the electric motor 14 and driven to rotate integrally with the output shaft 20. The orbiting scroll is rotatable relative to the fixed scroll. The fixed scroll and the orbiting scroll each have a spiral wall extending in a spiral shape. For example, the fixed scroll and the orbiting scroll are arranged in different orientations with a phase difference in the circumferential direction (the direction of rotation of the output shaft 20), and the spiral wall of the orbiting scroll is inserted radially between the spiral walls of the fixed scroll. The volume of a compression chamber formed by the gap between the spiral walls changes depending on the relative orientation (amount of rotation) of the orbiting scroll relative to the fixed scroll in the circumferential direction. A working fluid consisting of a liquid or gas is sealed in the compression chamber.

[0030] The orbiting scroll is attached to an output shaft 20 of the electric motor 14 and is arranged in series with respect to the electric motor 14 in the axial direction (left-right direction) of the output shaft 20. The orbiting scroll and the fixed scroll are arranged substantially coaxially facing each other, and therefore a scroll member 16 formed by the orbiting scroll and the fixed scroll is arranged in series with respect to the electric motor 14 in the axial direction along which the output shaft 20 extends (output axis direction) and is arranged inside a case 18.

[0031] When the orbiting scroll is driven to rotate by the output of the electric motor 14, the working fluid introduced into the compression chamber from a suction port (not shown) is compressed by a change in the volume of the compression chamber, and the compressed working fluid is discharged from a discharge port (not shown) to an external flow path. Note that, for example, in the scroll member 16, the suction port is provided at the outer peripheral end (outer peripheral end) of the fixed scroll and the orbiting scroll, and the discharge port is provided at the outer peripheral end (center) of the fixed scroll and the orbiting scroll.

[0032] The electric compressor 12 thus constructed is supported in a vibration-isolating manner on a vehicle body member 40 (described later) by a rubber mount 24 serving as a vibration-isolating device. As shown in Figures 4 and 5, the rubber mount 24 is a cylindrical vibration-isolating device in which an inner shaft member 26 and an outer cylindrical member 28 are interconnected by a main rubber elastic body 30.

[0033] The inner shaft member 26 has a small diameter and a generally cylindrical shape. The inner shaft member 26 is a highly rigid member made of, for example, metal or fiber-reinforced synthetic resin. The outer tubular member 28 has a large diameter and a generally cylindrical shape. The outer tubular member 28 has an inner flange-shaped stopper portion 32 that protrudes from one axial end toward the inner circumference. The outer tubular member 28 is a highly rigid member made of, for example, metal or fiber-reinforced synthetic resin.

[0034] The main rubber elastic body 30 has an inner peripheral end portion that is a small-diameter cylindrical inner peripheral fixing portion 34 that is fixed to the outer peripheral surface of the inner shaft member 26. The main rubber elastic body 30 has a cup-shaped connecting portion 36 that extends outward from the inner peripheral fixing portion 34. The connecting portion 36 projects in the axis-perpendicular direction from the inner peripheral fixing portion 34 and extends in the axial direction while bending and widening midway, and has an end that is fixed to a stopper portion 32 of the outer tubular member 28. A stopper rubber 38 that projects in the axial direction toward a vehicle body side member 40 (described later) is fixed to the stopper portion 32 of the outer tubular member 28, and in this embodiment, the stopper rubber 38 is formed integrally with the main rubber elastic body 30.

[0035] The rubber mount 24 has an inner shaft member 26 attached to the case 18 of the electric compressor 12, and an outer cylindrical member 28 attached to a vehicle body side member 40. The method for fastening the inner shaft member 26 to the case 18 is not particularly limited, but for example, they are bolted together by a bolt (not shown) inserted into the inner shaft member 26. The method for fastening the outer cylindrical member 28 to the vehicle body side member 40 is not particularly limited, but for example, the outer cylindrical member 28 is press-fitted into a mounting hole provided in the vehicle body side member 40.

[0036] 1 to 3, the rubber mounts 24 constituting the electric compressor support structure 10 are four in number: first rubber mounts 24a, 24a serving as first vibration-isolating devices, and second rubber mounts 24b, 24b serving as second vibration-isolating devices. In this embodiment, the first rubber mount 24a and the second rubber mount 24b are identical to each other. However, the first rubber mount 24a and the second rubber mount 24b may have different structures.

[0037] The two first rubber mounts 24a, 24a are arranged on the torque pitch axis A of the electric compressor 12, which is indicated by a dashed line in FIGS. 1 to 3. The two first rubber mounts 24a, 24a are arranged on both sides of the case 18 of the electric compressor 12 in the extension direction of the torque pitch axis A. Each first rubber mount 24a is attached to the electric compressor 12 with its central axis direction approximately aligned with the extension direction of the torque pitch axis A. Here, the central axis direction of the first rubber mount 24a being approximately aligned with the extension direction of the torque pitch axis A does not necessarily mean that they are strictly aligned, but also includes cases where they are inclined relative to each other at an angle of 20 degrees or less. The two first rubber mounts 24a, 24a are arranged axially in opposite directions.

[0038] 6, the two first rubber mounts 24a, 24a are located at approximately the same distance from the center of gravity G of the electric compressor 12. The difference in the distance between the two first rubber mounts 24a, 24a and the center of gravity G of the electric compressor 12 is preferably 20% or less of the shorter distance, and more preferably, they are designed to be the same.

[0039] The two second rubber mounts 24b, 24b are arranged on the torque yaw axis B of the electric compressor 12, which is indicated by the dashed dotted line in FIGS. 1 to 3. The two second rubber mounts 24b, 24b are arranged on both sides of the case 18 of the electric compressor 12 in the extension direction of the torque yaw axis B. Each second rubber mount 24b is attached to the electric compressor 12 with its central axis direction approximately aligned with the extension direction of the torque yaw axis B. Here, the central axis direction of the second rubber mount 24b approximately aligned with the extension direction of the torque yaw axis B does not necessarily mean that they are strictly aligned, but also includes cases where they are inclined relative to each other at an angle of 20 degrees or less. The two second rubber mounts 24b, 24b are arranged facing opposite directions in the axial direction.

[0040] 6, the two second rubber mounts 24b, 24b are located at approximately the same distance from the center of gravity G of the electric compressor 12. The difference in the distance between the two second rubber mounts 24b, 24b and the center of gravity G of the electric compressor 12 is preferably 20% or less of the shorter distance, and more preferably, they are the same in design.

[0041] 1 to 3, the first rubber mounts 24a, 24a and the second rubber mounts 24b, 24b are both shown in positions away from the electric compressor 12, but the first rubber mounts 24a, 24a and the second rubber mounts 24b, 24b arranged in such positions have their inner shaft members 26 indirectly attached to the electric compressor 12 via a bracket (not shown). However, the inner shaft members 26 of the first rubber mounts 24a, 24a and the second rubber mounts 24b, 24b may also be attached directly to the case 18 of the electric compressor 12 without using a separate member such as a bracket.

[0042] The torque pitch axis A and torque yaw axis B of the electric compressor 12 are two other torque axes that intersect with the torque roll axis and intersect with each other at the center of gravity G of the electric compressor 12. The torque pitch axis A and torque yaw axis B of the electric compressor 12 extend in a direction that intersects with the axial direction of the output shaft 20 of the electric motor 14. The torque roll axis is the torque axis (rotation axis) of the electric compressor 12 that has the smallest angle of inclination with respect to the axial direction of the output shaft 20 of the electric motor 14, and can be calculated using the inertia tensor I (described later) in the same way as the torque pitch axis A and torque yaw axis B.

[0043] The torque pitch axis A and the torque yaw axis B can be determined, for example, by the following calculation for the electric compressor 12 disposed in a coordinate space having mutually orthogonal coordinate axes of X, Y, and Z as shown in FIG. 6. The orientation of the electric compressor 12 with respect to the coordinate axes can be set arbitrarily, and each of the torque pitch axis A and the torque yaw axis B is determined according to the orientation of the electric compressor 12 with respect to the coordinate axes. The orientation of the electric compressor 12 with respect to the coordinate axes is not particularly limited, but in FIG. 6, when the electric compressor 12 is mounted on the vehicle, the X axis is set to the vehicle's fore-and-aft direction (the up-and-down direction in FIG. 1), the Y axis is set to the vehicle's left-and-right direction (the left-and-right direction in FIG. 1), and the Z axis is set to the vertical up-and-down direction (the up-and-down direction in FIG. 2). Note that in FIG. 6, for simplicity, the electric compressor 12 is shown as being cylindrical, and the rubber mount 24 is shown as being spherical.

[0044] That is, first, the moment of inertia tensor I (hereinafter referred to as inertia tensor I) is calculated as shown in [Equation 1]. As shown in [Equation 1], the inertia tensor I is a 3 × 3 determinant, and is determined by the shape and mass distribution of the electric compressor 12, and therefore can be calculated based on the measured values ​​and design values ​​thereof. Note that the inertia tensor I can also be calculated, for example, by measuring the inertia tensors of the principal axes of inertia and then performing coordinate transformation on the inertia tensors of the principal axes of inertia.

[0045]

number

[0046] The torque pitch axis A and the torque yaw axis B can be recognized as each of the central axes of rotation of the electric compressor 12 when the electric compressor 12 is operating, and can be identified by calculation or experiment using a known method once the electric compressor 12 is specifically identified. If the product of inertia (terms other than the diagonal terms) in the inertia tensor I of [Equation 1] is 0, the torque pitch axis A and the torque yaw axis B can be recognized as each of the principal axes of inertia of the electric compressor 12, and together with the principal axis of inertia (torque roll axis) extending substantially along the direction of the output shaft 20 of the electric compressor 12 and the central axis of rotation of the scroll member 16, they form three orthogonal axes. Although the electric compressor 12 is a rigid body, if the mass distribution and moment of inertia change due to the rotation of the scroll member 16, or if the product of inertia does not become zero due to fixed support conditions (via a mount) of the electric compressor 12 on the vehicle body side, the calculated torque pitch axis A and torque yaw axis B will not satisfy the orthogonal condition.

[0047] Next, the direction vector α of the torque pitch axis A is calculated using the calculation shown in [Equation 2]. The torque pitch axis A is a straight line that passes through the coordinates of the center of gravity G of the electric compressor 12 with the direction vector α calculated using [Equation 2].

[0048]

number

[0049] Next, the direction vector β of the torque yaw axis B is calculated using the calculation shown in [Equation 3]. The torque yaw axis B is a straight line that passes through the coordinates of the center of gravity G of the electric compressor 12 with the direction vector β calculated using [Equation 3].

[0050]

number

[0051] First rubber mounts 24a are disposed on both sides of case 18 in the extension direction of calculated torque pitch axis A. First rubber mounts 24a are disposed within a region where inclination angle θ1 with respect to torque pitch axis A is ±20 degrees. In other words, it is sufficient that at least a portion of first rubber mount 24a is located within a conical region whose inclination angle θ1 with respect to torque pitch axis A is 20 degrees. The conical region is a right circular cone whose apex is located at the center of gravity G of electric compressor 12 and whose apex angle is 40 degrees, and the axis of rotational symmetry passing through the apex is torque pitch axis A. In this embodiment, at least a portion of first rubber mounts 24a, 24a is located on torque pitch axis A. More preferably, the center of gravity of first rubber mounts 24a, 24a is located on torque pitch axis A.

[0052] Additionally, second rubber mounts 24b are disposed on both sides of the case 18 in the extension direction of the calculated torque yaw axis B. The second rubber mounts 24b are disposed within a region where the inclination angle θ2 with respect to the torque yaw axis B is ±20 degrees. In other words, it is sufficient that at least a portion of the second rubber mounts 24b is located within a conical region in which the inclination angle θ2 with respect to the torque yaw axis B is 20 degrees. The conical region is a right circular cone with an apex at the center of gravity G of the electric compressor 12 and an apex angle of 40 degrees, and the axis of rotational symmetry passing through the apex is the torque yaw axis B. At least a portion of the second rubber mounts 24b, 24b in this embodiment is located on the torque yaw axis B. More preferably, the centers of gravity of the second rubber mounts 24b, 24b are located on the torque yaw axis B.

[0053] In the electric compressor 12, when the orbiting scroll of the scroll member 16 is driven to rotate by the output of the electric motor 14, the orbiting scroll rotates as an eccentric mass, generating a moment M1 with the torque pitch axis A as its central axis and a moment M2 with the torque yaw axis B as its central axis, as shown in FIG. 6.

[0054] Due to the moment M2 around the torque yaw axis B, loads F1 and F2 act in opposite directions on the first rubber mounts 24a, 24a, which are disposed at a distance from the torque yaw axis B. In this embodiment, because the first rubber mounts 24a, 24a are located at the same distance from the center of gravity G, through which the torque yaw axis B passes, the loads F1 and F2 due to the moment M2 are approximately the same magnitude.

[0055] Furthermore, due to moment M1 around torque pitch axis A, loads F3 and F4 act in opposite directions on second rubber mounts 24b, 24b that are disposed away from torque pitch axis A. In this embodiment, the second rubber mounts 24b are located at the same distance from center of gravity G, through which torque pitch axis A passes, so the loads F3 and F4 due to moment M1 have approximately the same magnitude.

[0056] The first rubber mounts 24a are disposed within a region where the inclination angle θ1 with respect to the torque pitch axis A is ±20 degrees. In this embodiment, the first rubber mounts 24a are disposed on the torque pitch axis A, which reduces transmission of moment M1 about the torque pitch axis A to the vehicle body member 40 via the first rubber mounts 24a. In particular, because the first rubber mounts 24a are cylindrical vibration-damping devices, moment M1 acts on the first rubber mounts 24a mainly as a torsional input about the central axis. Therefore, the low torsional rigidity of the first rubber mounts 24a makes it possible to set the resonant frequency of the electric compressor support structure 10 to a lower frequency.

[0057] The loads F1 and F2 caused by the moment M2 acting on the first rubber mounts 24a are transmitted to the vehicle body side member 40 via the first rubber mounts 24a. However, because the loads F1 and F2 are applied to the vehicle body side member 40 with the same magnitude but in opposite directions, they cancel each other out at the vehicle body side member 40. As a result, vibration of the vehicle body side member 40 caused by the transmission of the loads F1 and F2 from the electric compressor 12 is reduced.

[0058] Similarly, the second rubber mounts 24b are disposed within a region where the inclination angle θ2 with respect to the torque yaw axis B is ±20 degrees. In this embodiment, the second rubber mounts 24b are disposed on the torque yaw axis B, which reduces the transmission of the moment M2 about the torque yaw axis B to the vehicle body member 40 via the second rubber mounts 24b. In particular, the second rubber mounts 24b are cylindrical vibration-damping devices, and the moment M2 acts on the second rubber mounts 24b mainly as a torsional input about the central axis. Therefore, the low torsional rigidity of the first rubber mounts 24a makes it possible to set the resonant frequency of the electric compressor support structure 10 to a lower frequency.

[0059] The loads F3 and F4 caused by the moment M1 acting on the second rubber mounts 24b are transmitted to the vehicle body side member 40 via the second rubber mounts 24b. However, because the loads F3 and F4 are applied to the vehicle body side member 40 with the same magnitude but in opposite directions, they cancel each other out at the vehicle body side member 40. As a result, vibration of the vehicle body side member 40 caused by the transmission of the loads F3 and F4 from the electric compressor 12 is reduced.

[0060] Furthermore, since the vehicle body side member 40 has a sufficiently large mass compared to the electric compressor 12, when loads F1, F2 due to moment M2 or loads F3, F4 due to moment M1 are input from the electric compressor 12, the displacement of the vehicle body side member 40 due to the input of such loads has almost no effect on the vibration state.

[0061] Incidentally, the fact that the support structure 10 for an electric compressor according to the above-described embodiment exhibits better vibration-damping performance than the support structure for an electric compressor according to the conventional structure can also be confirmed by the graph of simulation results shown in FIG.

[0062] 8 to 10 show a support structure 50 for an electric compressor according to a conventional structure used in the simulation that produced the results of FIG. 7. The support structure 50 for an electric compressor supports the same electric compressor 12 as in the above embodiment using the same rubber mounts 24 as in the above embodiment. In addition, the support structure 50 for an electric compressor has at least one rubber mount 24 positioned outside both the range of ±20 degrees in inclination angle relative to the torque pitch axis A and the range of ±20 degrees in inclination angle relative to the torque yaw axis B.

[0063] The graph in Figure 7 shows the frequency characteristics of the transmission force when vibrations caused by the eccentric rotation of the orbiting scroll are applied. According to Figure 7, the transmission force of the support structure 10 for an electric compressor according to this embodiment, indicated by the solid line, is smaller than the transmission force of the support structure 50 for an electric compressor according to the conventional structure, indicated by the dashed line. Therefore, the simulation results also confirm that the support structure 10 for an electric compressor according to this embodiment exhibits better vibration-damping performance than the support structure 50 for an electric compressor according to the conventional structure when vibrations caused by the eccentric rotation of the orbiting scroll are applied.

[0064] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the specific descriptions. For example, rubber mount 24a may be entirely spaced apart from torque pitch axis A as long as its inclination angle θ1 with respect to torque pitch axis A is within a range of ±20 degrees. Similarly, rubber mount 24b may be entirely spaced apart from torque yaw axis B as long as its inclination angle θ2 with respect to torque yaw axis B is within a range of ±20 degrees.

[0065] Two or more rubber mounts 24a may be arranged on at least one side of case 18 as long as they are arranged on both sides of case 18, but even in this case, all of the rubber mounts 24a are arranged so that the inclination angle θ1 with respect to the torque pitch axis A is within the range of ±20 degrees. Similarly, two or more rubber mounts 24b may be arranged on at least one side of case 18 as long as they are arranged on both sides of case 18, but even in this case, all of the rubber mounts 24b are arranged so that the inclination angle θ2 with respect to the torque yaw axis B is within the range of ±20 degrees.

[0066] The structure of the rubber mount 24 is merely an example, and for example, even in a cylindrical vibration damping device, the specific shapes, sizes, materials, etc. of the inner shaft member 26, outer cylindrical member 28, and main rubber elastic body 30 can be changed as appropriate. The direction in which the rubber mount 24 is attached to the electric compressor 12 is preferably such that low spring characteristics due to the torsional spring component are exhibited against the moment around the torque axis as shown in the above embodiment, but is not particularly limited.

[0067] Furthermore, in the above embodiment, the rubber mount 24, which is a cylindrical vibration-damping device, is used as an example of the vibration-damping device, but the vibration-damping device is not limited to a cylindrical vibration-damping device, and it is also possible to use, for example, a vibration-damping device having a structure in which a first mounting member and a second mounting member are fixed to both sides of a main rubber elastic body. Furthermore, the vibration-damping device may be, for example, a fluid-filled type vibration-damping device that uses the flow action of a fluid sealed inside, a switchable vibration-damping device that is capable of switching vibration-damping characteristics, or an active vibration-damping device that reduces vibration by offsetting it with an active excitation force. [Explanation of symbols]

[0068] 10 Support structure for electric compressor (first embodiment) 12 Electric compressor 14 Electric motor 16 Scroll member (compression mechanism part) 18 cases 20 Output shaft 22 Storage unit body 24 Rubber mount (vibration isolation device) 24a First rubber mount (first vibration isolation device) 24b Second rubber mount (second vibration isolation device) 26 Inner shaft member 28 Outer cylindrical member 30 Main body rubber elastic body 32 Stopper part 34 Inner circumference fixing part 36 Connecting part 38 Stopper rubber 40 Vehicle body side member 50 Electric compressor support structure (comparison example) A Torque pitch axis B Torque yaw axis G Center of gravity of electric compressor θ1 Inclination angle relative to the torque pitch axis θ2 Inclination angle relative to the torque yaw axis M1 Torque moment around pitch axis M2 torque moment around the yaw axis F1 Load caused by moment M2 acting on one of the first rubber mounts F2 Load caused by moment M2 acting on the other first rubber mount F3 Load caused by moment M1 acting on one of the second rubber mounts F4 Load caused by moment M1 acting on the other second rubber mount

Claims

1. A support structure for an electric compressor that supports an electric compressor on a vehicle body side member in a vibration-isolating manner using a vibration-isolating device, The electric compressor includes a scroll-type compression mechanism that is rotationally driven by an electric motor, The electric motor and the compression mechanism are arranged in series in the output shaft direction, which is the direction in which the output shaft of the electric motor extends, and are housed in a case. the vibration isolation device includes a first vibration isolation device and a second vibration isolation device; the first vibration isolation devices are disposed on both sides of the case in an extension direction of a torque pitch axis that intersects with the output shaft direction of the electric motor, and the second vibration isolation devices are disposed on both sides of the case in an extension direction of a torque yaw axis that intersects with the output shaft direction and the torque pitch axis of the electric motor, A support structure for an electric compressor, wherein the first vibration isolation device is arranged within a range of ±20 degrees inclination angle relative to the torque pitch axis, and the second vibration isolation device is arranged within a range of ±20 degrees inclination angle relative to the torque yaw axis.

2. 2. The support structure for an electric compressor according to claim 1, wherein at least a portion of each of the first vibration isolation devices is located on the torque pitch axis, and at least a portion of each of the second vibration isolation devices is located on the torque yaw axis.

3. 3. A support structure for an electric compressor as described in claim 1 or 2, wherein one first vibration isolation device is arranged on each side of the electric compressor in the direction in which the torque pitch axis extends relative to the case, and one second vibration isolation device is arranged on each side of the electric compressor in the direction in which the torque yaw axis extends relative to the case.

4. the first vibration-damping device and the second vibration-damping device are cylindrical vibration-damping devices in which an inner shaft member and an outer cylindrical member are connected by a main rubber elastic body, 3. A support structure for an electric compressor as described in claim 1 or 2, wherein the axial direction of the inner shaft member of the first vibration isolation device attached to the case of the electric compressor is aligned with the extension direction of the torque pitch axis, and the axial direction of the inner shaft member of the second vibration isolation device attached to the case of the electric compressor is aligned with the extension direction of the torque yaw axis.

5. a difference between a distance from the first vibration-damping device disposed on one side of the case to the center of gravity of the electric compressor and a distance from the first vibration-damping device disposed on the other side of the case to the center of gravity of the electric compressor is set to 20% or less of the shorter distance, A support structure for an electric compressor as described in claim 1 or 2, wherein the difference between the distance from the second vibration isolation device arranged on one side of the case to the center of gravity of the electric compressor and the distance from the second vibration isolation device arranged on the other side of the case to the center of gravity of the electric compressor is 20% or less of the shorter distance.

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