JP2017100611A - In-vehicle structure of power control device - Google Patents

Abstract

A technique for suppressing a moment generated in a power control device due to an inertial force in a translation direction is provided. A PCU 6 (power control device) is supported by mounts 10 and 20 on the front and rear surfaces of the casing. The distance in the vertical direction between the connecting portion 10a between the housing and the mount 10 and the center of gravity G is a distance r1, and the distance in the vertical direction between the connecting portion 20a between the housing and the mount 20 and the center of gravity G is a distance r2. The spring constant of the mount 10 at 10a is a first spring constant k1, and the spring constant of the mount 20 at the connection location 20a is a second spring constant k2. The moment generated around the Y axis of the center of gravity G by the spring forces F1 and F2 received from the mounts 10 and 20 when the PCU 6 receives the inertial force Fh is greater than the moment when the first and second spring constants k1 and k2 are the same. The spring constant of the shorter mount of the distances r1 and r2 is set to be larger than the spring constant of the longer mount so that the distance r1 and r2 is smaller. [Selection] Figure 5

Description

  The present invention relates to a vehicle-mounted structure of a power control device that controls power supplied to a traveling motor.

  Since the power control device that controls the power supplied to the motor for traveling is a device that handles large power, it is relatively large in size. When considering its in-vehicle structure, it is necessary to take measures against vibration. Patent Document 1 discloses an example of a vehicle-mounted structure of a power control device. According to Patent Document 1, the casing of the power control device is fixed at the front and rear surfaces, and the center of gravity of the power control device, the front fixing location and the rear fixing location are aligned on a straight line when viewed from the side of the vehicle. It is said that stable support can be performed against vibrations such as balance and pitch.

  On the other hand, as an in-vehicle structure of the power control device, mounts (fixing brackets) are connected to the front and rear portions of the power control device housing, and a gap is formed between the power control device and the upper surface of the motor unit. There is a case where a structure that has and supports the motor unit is employed (Patent Document 2). The motor unit may include not only a traveling motor but also a gear set. For example, the motor unit of Patent Document 2 includes, in addition to the traveling motor, a power distribution mechanism that combines / distributes the output torque of the traveling motor and the output torque of the engine, and a differential gear. Hereinafter, for convenience of explanation, the traveling motor may be simply referred to as a motor.

JP 10-053028 A JP 2014-114870 A

  When the power control device is supported with respect to the motor unit with a gap between the upper surface of the motor unit as in the on-vehicle structure of Patent Document 2, the inertial force (excitation force in the translation direction) is applied to the power control device. ) Can induce a moment around the center of gravity. The inertial force acting on the power control device is, for example, an inertial force caused by acceleration / deceleration of the vehicle, an inertial force caused by vibration of the motor unit, or the like. The moment may twist the fixed portion of the power control apparatus and cause damage to the fixed portion. In the technique of Patent Document 1, the fixed location is determined so that the fixed location on the center of gravity, the fixed location on the front surface, and the fixed location on the rear surface are aligned on a straight line as viewed from the side of the vehicle. The vertical distance between each fixed location and the center of gravity If they are different, a moment is induced around the center of gravity due to the inertial force in the front-rear direction. In the present specification, the power control device is caused by the inertial force in the translational direction when the in-vehicle structure is used in which the power control device is supported by the motor unit with a gap between the motor unit and the upper surface. The technology which suppresses the moment which occurs is provided.

  The following in-vehicle structure contributes to the moment reduction with respect to the completion force in the longitudinal direction of the vehicle. The power control device is supported by the motor unit that houses the traveling motor by the first and second mounts. One end of the first mount is connected to one of the front part and the rear part of the casing of the power control device, and the other end is connected to the motor unit. One end of the second mount is connected to the other of the front part and the rear part of the power control device, and the other end is connected to the motor unit. And the height of the connection location (1st connection location) of a housing | casing and a 1st mount is lower than the height of the gravity center of a power control apparatus, and the connection location (2nd connection location) of a housing | casing and said 2nd mount. Is higher than the center of gravity. Further, the vertical distance between the first connection location and the center of gravity is the first distance, the vertical distance between the second connection location and the center of gravity is the second distance, and the vehicle front-rear direction of the first mount at the first connection location is the second distance. The first and second spring constants are set as follows, where the first spring constant is the first spring constant and the second spring constant is the spring constant in the vehicle longitudinal direction of the second mount at the second connection location. That is, when the power control device receives a completion force in the vehicle front-rear direction, the moment generated around the axis of the center of gravity in the vehicle width direction by the spring force received from the first and second mounts is the first and second spring constants. Of the first distance and the second distance, the spring constant of the shorter mount of the first distance and the second distance is set larger than the spring constant of the longer mount. In order to reduce the moment due to the inertial force in the vehicle width direction, “vehicle longitudinal direction” and “vehicle width direction” in the above description should be read as “vehicle width direction” and “vehicle longitudinal direction”, respectively. . The reason why the moment around the center of gravity is suppressed when the spring constant is set as described above in relation to the first distance and the second distance will be described in the following “Mode for Carrying Out the Invention”.

It is a perspective view which shows the components layout of the engine room of the hybrid vehicle containing the vehicle-mounted structure of an Example. It is a side view of a motor unit and PCU. It is a front view of PCU supported by the motor unit. FIG. 4 is a sectional view taken along line IV-IV in FIG. 3. It is a side view explaining the relationship of the force which acts on PCU. It is sectional drawing which shows a reference vehicle-mounted structure. It is sectional drawing of a reference front mount (before front bracket deformation). It is sectional drawing of a reference front mount (at the time of a front bracket deformation | transformation).

  An in-vehicle structure of an embodiment will be described with reference to the drawings. The on-vehicle structure of the embodiment is applied to the hybrid vehicle 90. FIG. 1 shows a component layout of the engine room 94 of the hybrid vehicle 90. The hybrid vehicle 90 includes a motor unit 2 including a traveling motor 3, a power control device 6 that controls power supplied to the traveling motor 3, and an engine 97 in an engine room 94. In addition, the engine room 94 accommodates an auxiliary battery 98, a radiator 96, a relay box 92, an air conditioner compressor 93, and the like. FIG. 1 is a simplified illustration of the shape of the device in the engine room. The X axis in the figure corresponds to the vehicle longitudinal direction, the Y axis corresponds to the vehicle width direction, and the Z axis corresponds to the vertical direction of the vehicle. The meaning of each coordinate axis is the same in the subsequent figures.

  The motor unit 2 includes a travel motor 3, a power distribution mechanism 4, and a differential gear 5. The traveling motor 3, the power distribution mechanism 4, and the differential gear 5 are accommodated in the housing of the motor unit 2. The engine 97 and the motor unit 2 are fixed to two side members 95 constituting a chassis frame. In FIG. 1, one side member is hidden and cannot be seen.

  The motor unit 2 is a transaxle for a hybrid vehicle commonly called a multi-shaft type. The upper surface of the motor unit 2 is inclined forward. The power control device 6 is supported on the upper surface. The power control device 6 is supported by the front mount 10 and the rear mount 20 with a gap between the upper surface of the motor unit 2. The power control device 6 boosts the DC power of a high voltage battery (not shown), converts it to a three-phase AC of a predetermined frequency, and supplies it to the traveling motor 3. That is, the power control device 6 controls the power supplied to the traveling motor 3. Hereinafter, for convenience of explanation, the power control device 6 may be referred to as a PCU 6 (Power Control Unit).

  The in-vehicle structure 100 of the PCU 6 will be described in detail with reference to FIGS. FIG. 2 is a side view of the PCU 6 supported above the motor unit 2. FIG. 3 is a front view of the PCU 6 supported above the motor unit 2.

  As described above, the motor unit 2 includes the traveling motor 3, the power distribution mechanism 4 that combines the output torque of the traveling motor 3 and the output torque of the engine 97, and the differential gear 5. The motor unit 2 is a multi-shaft type, and the output shaft (motor output shaft 3a) of the traveling motor 3, the main shaft 4a of the power distribution mechanism 4, and the shaft 5a of the differential gear 5 are arranged in the vehicle width direction (Y direction in the figure). ) Extending in parallel with. That is, the motor unit 2 accommodates the traveling motor 3 such that the motor output shaft 3a extends in the vehicle width direction. The three shafts extend in the vehicle width direction. Therefore, the upper surface of the motor unit 2 is inclined forward and downward. As described above, the PCU 6 is supported by the front mount 10 and the rear mount 20 with a gap between the upper surface of the motor unit 2. The PCU 6 is supported above the motor unit 2 in a forward-downward posture. Therefore, the connection location between the front mount 10 and the PCU 6 is lower than the connection location between the rear mount 20 and the PCU 6.

  The motor output shaft 3a is interlocked with the axle. Due to the unevenness of the road surface, the wheel leaves or contacts the road surface again. Each time the wheel leaves or contacts the road surface, a pulsed torque reaction force is generated on the motor output shaft 3a. Further, since the motor output shaft 3a is also coupled to the output shaft of the engine 97 via a gear, vibration of the engine 97 is also propagated to the motor output shaft 3a. Therefore, the PCU 6 supported above the motor unit 2 receives a pulsed or oscillating inertial force (translational inertial force) in the vehicle longitudinal direction (X direction in the figure). Such an inertial force becomes a vibration source that vibrates the PCU 6. In order to reduce the influence of the pulsed or vibrational inertial force received by the PCU 6, the PCU 6 is supported above the motor unit 2 with a gap by the front mount 10 and the rear mount 20. The rear mount 20 includes anti-vibration bushes 13 and 23. Hereinafter, the front mount 10 and the rear mount 20 may be collectively referred to as mounts 10 and 20.

  The lower end of the front mount 10 is connected to the upper surface of the motor unit 2 by a bolt 31, and the upper end is connected to the housing front surface 6 a of the PCU 6 by a bolt 32. The front mount 10 includes a metal bracket 12 and a vibration isolating bush 13. The anti-vibration bush 13 is sandwiched between the bracket 12 and the PCU 6. The lower end of the rear mount 20 is connected to the upper surface of the motor unit 2 by a bolt 33, and the upper end is connected to the housing rear surface 6 b of the PCU 6 by a bolt 34. The rear mount 20 includes a metal bracket 22 and a vibration isolating bush 23. The anti-vibration bush 23 is sandwiched between the bracket 22 and the PCU 6.

  Since the motor output shaft 3a extends in the vehicle width direction, the PCU 6 supported above the motor unit 2 has a pulse-like or vibrational inertial force, particularly along the vehicle longitudinal direction, as described above. Receive. In the in-vehicle structure 100, the front surface 6a and the rear surface 6b of the PCU 6 are supported by the mounts 10 and 20 having the anti-vibration bushes 13 and 23, thereby reducing the influence of the inertial force in the vehicle front-rear direction that the PCU 6 receives. To do. The anti-vibration bushes 13 and 23 also have a reduction effect with respect to the inertia force in the vehicle width direction and the vertical direction, but in this specification, the description will be continued with a particular focus on the inertia force in the front-rear direction.

  As shown in FIG. 3, the bracket 12 of the front mount 10 is connected to the motor unit 2 by two bolts 31 arranged in the horizontal direction. The bolt 32 is connected to the PCU 6. Although the rear mount 20 is not shown from the rear, the rear mount 20 is also connected to the motor unit 2 by two bolts 33 arranged in the horizontal direction, and the upper end of the rear mount 20 is bolted via a vibration isolating bush 23 at two places. 34 is connected to the PCU 6. Since the front mount 10 and the rear mount 20 are connected to the PCU 6 on both sides in the vehicle width direction, the moment generated in the PCU 6 around the Z axis is small with respect to the vibration force of the PCU 6 in the vehicle longitudinal direction. On the other hand, the moment generated in the PCU 6 around the Y axis varies depending on the connection position between the mounts 10 and 20 and the PCU 6. The in-vehicle structure 100 has a mechanism for suppressing a moment generated in the PCU 6 around the Y axis. The mechanism will be described later. The Y axis direction is an axis extending in the vehicle width direction.

  The front mount 10 and the rear mount 20 will be described in detail with reference to FIG. FIG. 4 shows a cross section taken along line IV-IV in FIG. FIG. 4 is a cross-sectional view cut along a plane parallel to the XZ plane in the drawing and passing through the vibration isolating bushes 13 and 23. In FIG. 4, a part of the PCU 6 and a part of the motor unit 2 are not shown. The internal structure of the PCU 6 is not shown.

  First, the structure of the front mount 10 will be described. The anti-vibration bush 13 of the front mount 10 includes an inner cylinder 14, an outer cylinder 15, and a rubber bush 16. The inner cylinder 14 and the outer cylinder 15 are arranged coaxially. The inner cylinder 14 includes a flange 14a at one end in the axial direction. The outer cylinder 15 includes a flange 15a at one end on the same side as the flange 14a. A rubber bush 16 is sandwiched between the inner cylinder 14 and the outer cylinder 15 and between the flange 14a and the flange 15a. The inner cylinder 14 is connected to the housing front surface 6 a of the PCU 6 with a bolt 32, and the upper portion of the bracket 12 is fitted to the outer periphery of the outer cylinder 15. That is, the bracket 12 and the PCU 6 are not in direct contact with each other, and both are coupled via the rubber bush 16. The lower end of the bracket 12 is connected to the housing 2 a of the motor unit 2 by a bolt 31.

  The anti-vibration bush 23 of the rear mount 20 has the same structure as the anti-vibration bush 13. The anti-vibration bush 23 includes an inner cylinder 24, an outer cylinder 25, and a rubber bush 26. The inner cylinder 24 and the outer cylinder 25 are arranged coaxially. The inner cylinder 24 includes a flange 24a at one end in the axial direction. The outer cylinder 25 includes a flange 25a at one end on the same side as the flange 24a. A rubber bush 26 is sandwiched between the inner cylinder 24 and the outer cylinder 25 and between the flange 24a and the flange 25a. The inner cylinder 24 is connected to the housing rear surface 6 b of the PCU 6 with a bolt 34, and the upper portion of the bracket 22 is fitted to the outer periphery of the outer cylinder 25. The bracket 22 and the PCU 6 are not in direct contact with each other, and both are coupled via a rubber bush 26. The lower end of the bracket 22 is connected to the housing 2 a of the motor unit 2 by a bolt 33.

  By providing the anti-vibration bushes 13 and 23, the front mount 10 and the rear mount 20 reduce the vibration (inertial force) of the motor unit 2 transmitted to the PCU 6. As described above, since the motor output shaft 3a extends in the vehicle width direction, the PCU 6 receives a pulsed or vibrational inertial force (excitation force) in the vehicle longitudinal direction (X direction in the figure). The anti-vibration bushes 13 and 23 suppress vibration in the front-rear direction of the PCU 6. On the other hand, when a moment about the Y axis is generated in the PCU 6 due to the inertial force in the front-rear direction, the rubber bushings 16 and 26 are twisted about the Y axis in the drawing. When the rubber bushings 16 and 26 are repeatedly twisted, deterioration is promoted. That is, the mounts 10 and 20 supporting the PCU 6 are damaged. In the vehicle-mounted structure 100 of the embodiment, the mounting positions and rigidity of the front mount 10 and the rear mount 20 are adjusted so that the moment around the Y axis of the PCU 6 can be suppressed in order to suppress the twist generated in the rubber bushes 16 and 26. Yes. Next, a mechanism for suppressing the moment around the center of gravity Y axis of the PCU 6 will be described.

  FIG. 5 is the same view as FIG. 3, but omits reference numerals for some parts and instead shows the longitudinal force acting on the PCU 6. As described above, since the motor output shaft 3a extends in the vehicle width direction, the PCU 6 receives an inertial force serving as a vibration source, particularly in the vehicle front-rear direction (X direction in the figure). In FIG. 5, the inertial force in the vehicle front-rear direction acting on the PCU 6 is represented by the symbol Fh. The inertial force Fh balances with the spring force F1 of the front mount 10 and the spring force F2 of the rear mount 20. Here, the spring force F <b> 1 is caused by the bending rigidity of the bracket 12 of the front mount 10 and the elastic force of the rubber bush 16. The spring force F2 results from the bending rigidity of the bracket 22 of the rear mount 20 and the elastic force of the rubber bush 26. A moment M around the Y axis is generated at the center of gravity G of the PCU 6 by the spring forces F1 and F2. A connecting portion between the front mount 10 and the PCU 6 is denoted by reference numeral 10a, and a connecting portion between the rear mount 20 and the PCU 6 is denoted by reference numeral 20a. The vertical distance between the connection location 10a of the front mount 10 and the center of gravity G of the PCU 6 is defined as a first distance r1, and the vertical distance between the connection location 20a of the rear mount 20 and the center of gravity G is defined as a second distance r2. . In FIG. 5, when the counterclockwise moment is positive, the moment M can be expressed by M = F1 × r1−F2 × r2 (Formula 1). As shown in FIG. 5, the height of the connection point 10a of the front mount 10 from the ground is lower than the height of the center of gravity G from the ground, and the height of the connection point 20a of the rear mount 20 from the ground. Is higher than the height of the center of gravity G from the ground. Therefore, the moment M is represented by the difference between the moment “F1 × r1” due to the spring force F1 and the moment “F2 × r2” due to the spring force F2.

  On the other hand, the front-rear direction rigidity (spring constant) of the front mount 10 at the connection location 10a is k1, and the front-rear rigidity (spring constant) of the rear mount 20 at the connection location 20a is k2. Further, the amount of movement of the PCU 6 in the front-rear direction due to the inertial force Fh is represented by the symbol dx. Then, the spring force F1 of the front mount 10 can be expressed by F1 = k1 × dx (Formula 2), and the spring force F2 of the rear mount 20 can be expressed by F2 = k2 × dx (Formula 3). Substituting Equation 2 and Equation 3 into Equation 1, M = (k1 * r1-k2 * r2) * dx (Expression 4).

  From Equation 4, the moment M is zero when k1 = C / r1 and k2 = C / r2. In other words, if k1 × r1 = k2 × r2 holds, the moment M about the Y axis generated at the center of gravity G of the PCU 6 becomes zero. In summary, when the following condition is satisfied, the moment about the Y-axis of the PCU 6 caused by the inertial force in the front-rear direction becomes zero. The height of the connecting portion 10a between the housing of the PCU 6 and the front mount 10 is lower than the height of the center of gravity G of the PCU 6, and the height of the connecting portion 20a between the housing and the rear mount 20 is higher than the height of the center of gravity G. And k1 * r1 = k2 * r2 (Formula 5) is satisfy | filled.

  Even if Formula 5 does not hold, Formula 4 shows that the moment M can be reduced if the first distance r1> the second distance r2 and the spring constant k1 <the spring constant k2. Conversely, if the first distance r1 <the second distance r2, the moment M can be reduced if the spring constant k1> the spring constant k2. If the spring constants k1 and k2 are determined so that the moment M acting around the Y axis of the center of gravity G is smaller than the moment when the spring constants of the front and rear mounts are equal, it can be said that there is a moment reducing effect. . In addition, when the spring constants k1 and k2 of the front and rear mounts are equal to the case where they are different, there is the following relationship. Now, suppose that the spring constants of the front and rear mounts are equal, k1 = k2 = kx. Since the moving amount dx of the PCU 6 when the inertial force Fh acts is not changed, Fh = (k1 + k2) dx = 2kxdx (Formula 6). Therefore, a relationship of k1 + k2 = 2kx (Formula 7) is established between the spring constants kx when the spring constants k1 and k2 of the front and rear mounts are equal to each other.

  Even when the height of the connecting portion 10a between the housing of the PCU 6 and the front mount 10 is higher than the height of the center of gravity G, and the height of the connecting portion 20a between the housing and the rear mount 20 is lower than the height of the center of gravity G. It can be seen that the condition is met.

  In summary, when one of the front mount 10 and the rear mount 20 is referred to as a first mount and the other is referred to as a second mount, the center of gravity Y of the PCU 6 caused by the inertial force in the vehicle front-rear direction has the following structure. The moment around the axis can be reduced. The height of the connecting portion between the housing of the PCU 6 and the first mount is lower than the height of the center of gravity of the PCU, and the height of the connecting portion between the housing and the second mount is higher than the height of the center of gravity. The first distance r1 is the vertical distance between the connection point (first connection point) of the first mount and the center of gravity, and the vertical distance between the connection point (second connection point) of the second mount and the center of gravity is the second distance. The distance r2 is set, the spring constant in the vehicle front-rear direction of the first mount at the first connection location is defined as the first spring constant, and the spring constant in the vehicle front-rear direction of the second mount at the second connection location is defined as the second spring constant. At this time, when the PCU 6 receives the inertial force in the longitudinal direction of the vehicle, the moment generated around the axis of the center of gravity in the vehicle width direction (around the Y axis) by the spring force received from the first and second mounts is Among the first distance r1 and the second distance r2, the spring constant of the shorter mount is set larger than the spring constant of the longer mount so that the two spring constants k1 and k2 are smaller than the moment. . Note that Equation 7 is established between the spring constant kx when the first and second spring constants are equal and the spring constant k1 and k2 when they are different. Therefore, it should be noted that the spring constant kx cannot be selected regardless of the spring constants k1 and k2.

  Note that one of the first mount and the second mount only needs to support one of the front part and the rear part of the housing of the PCU 6 and the other supports the other of the front part and the rear part. The connection point of the mount is not limited to the front surface or the rear surface of the housing.

  Further, preferably, the spring constants k1 and k2 are effective when the moment about the axis in the vehicle width direction of the center of gravity G of the PCU 6 caused by the inertial force in the front-rear direction is satisfied if k1 × r1 = k2 × r2 (Formula 5) is satisfied. Can be suppressed.

  Formula 5 indicates that when the first distance r1 and the second distance r2 are equal, the spring constant k1 of the first mount and the spring constant k2 of the second mount may be the same. However, Formula 5 and the structural features described above provide a degree of freedom for the first distance r1 and the second distance r2. In other words, the vehicle-mounted structure 100 according to the embodiment provides a degree of freedom in the positions of the connecting positions of the first mount (front mount 10) and the second mount (rear mount 20) to the PCU 6 in the front-rear direction. A moment around the center of gravity generated in the PCU 6 due to the inertial force can be suppressed.

  When the motor output shaft is accommodated in the motor unit so as to extend in the vehicle front-rear direction, the pulsed torque reaction force generated each time the wheel leaves the road surface or contacts the ground faces the vehicle width direction. At that time, an inertial force in the vehicle width direction acts on the PCU supported above the motor unit. In order to suppress the moment generated in the PCU with respect to the inertia force in the vehicle width direction, the first mount and the second mount may be connected to the right side and the left side of the PCU housing. In that case, the moment generated in the PCU due to the inertial force in the vehicle width direction can be suppressed by the following structural features. One end of the first mount is connected to one of the right side and the left side of the casing of the PCU, and the other end is connected to the motor unit. One end of the second mount is connected to the other of the right and left sides of the housing, and the other end is connected to the motor unit. The height of the connection location (first connection location) between the housing of the PCU and the first mount is lower than the height of the center of gravity of the PCU, and the height of the connection location (second connection location) between the housing and the second mount. Is higher than the height of the center of gravity. A vertical distance between the first connection location and the center of gravity is defined as a first distance, a vertical distance between the second connection location and the center of gravity is defined as a second distance, and a spring in the vehicle width direction of the first mount at the first connection location. The constant is the first spring constant k1, and the spring constant in the vehicle width direction of the second mount at the second connection location is the second spring constant k2. At this time, when the PCU receives the inertial force in the vehicle width direction, the moment generated around the axis of the center of gravity in the vehicle longitudinal direction by the spring force received from the first and second mounts is the first and second spring constants k1, Of the first distance r1 and the second distance r2, the spring constant of the shorter mount is set larger than the spring constant of the longer mount so that the moment is equal to k2.

  When the first and second mounts support the right and left sides of the housing, as in the previous case, if k1 × r1 = k2 × r2 (Equation 5) holds, it acts on the center of gravity of the PCU. The moment about the vehicle longitudinal axis can be effectively suppressed.

  A reference on-vehicle structure 200 for equalizing the first distance r1 and the second distance r2 will be described below. FIG. 6 shows a cross-sectional view along the XZ plane of the PCU 106 supported above the motor unit 102. FIG. 7 shows a cross-sectional view of the front mount 110. In the reference on-vehicle structure 200, a PCU 106 that controls power supplied to the traveling motor is supported above the housing 102a of the motor unit 102 that houses the traveling motor. The PCU 106 is supported by the motor unit 102 by the front mount 110 and the rear mount 120 with a gap between the upper surface of the housing 102a. The front mount 110 has an upper end connected to the front surface of the casing of the PCU 106 by a bolt 32 and a lower end connected to the motor unit 102 by a bolt 31. The rear mount 120 has an upper end connected to the rear surface of the casing of the PCU 106 by a bolt 34 and a lower end connected to the motor unit 102 by a bolt 33.

  The front mount 110 includes a metal bracket 112 and a vibration isolation bush 113. As shown in FIG. 7, the anti-vibration bush 113 includes an inner cylinder 114, an outer cylinder 115 disposed coaxially with the inner cylinder 114, and a rubber bush 16 sandwiched between them. A flange 114 a is provided at the end of the inner cylinder 114 far from the PCU 106, and a flange 115 a is provided on the same side as the flange 114 a of the outer cylinder 115. The rubber bush 16 is sandwiched between the inner cylinder 114 and the outer cylinder 115 and between the flange 114a and the flange 115a. A rib 114b extends from the upper end of the flange 114a of the inner cylinder 114. The rib 114 b reaches the PCU 106 while being curved, and the upper end is connected to the front surface of the PCU 106 by a bolt 32. The lower end of the metal bracket 112 is connected to the motor unit 102 by the bolt 31, and the upper end is fitted to the outer cylinder 115 of the vibration isolating bush 113. The metal bracket 112 is not in direct contact with the PCU 106, and is connected to the PCU 106 via a vibration isolating bush 113. Therefore, vibration caused by the inertial force in the front-rear direction received from the motor unit 102 is reduced by the vibration isolating bush 113. Although not shown in detail, the rear mount 120 has the same structure as that of the front mount 110. The rear mount 120 includes a bracket 122 and an anti-vibration bush 123. The tip of a rib 124b extending upward from the anti-vibration bush 123 is the PCU 106. Connected to the rear.

  As shown in FIG. 6, since the upper surface of the motor unit 102 is also inclined forward and downward, the PCU 106 is also supported above the motor unit 102 in a forwardly downward posture. Therefore, the height of the first connection location 110a between the housing of the PCU 106 and the front mount 110 is lower than the height of the center of gravity G of the PCU 106, and the height of the second connection location 120a between the housing and the rear mount 120 is the center of gravity. It is higher than the height of G.

  Since the front mount 110 can freely extend the rib 114b, the connection point with the PCU 106 can be selected relatively freely. The same applies to the rear mount 120. The rear mount 120 is connected to the PCU 106 by a rib 124b extending from an anti-vibration bush 123 on the upper portion thereof, and the rib 124b can be freely extended. Therefore, in the reference on-vehicle structure 200, the vertical distance (first distance r1) between the first connection location 110a and the center of gravity G and the vertical distance between the second connection location 120a and the center of gravity G (second distance). The first connection location 110a and the second connection location 120a can be selected so that r2) is equal. In the reference on-vehicle structure 200, since the first distance r1 and the second distance r2 are equal, the spring constant k1 of the front mount 110 of the front mount 110 at the first connection location 110a and the vehicle of the rear mount 120 at the second connection location 120a. The spring constant k2 in the front-rear direction is selected to be equal. In this case, since Equation 5 (k1 × r1 = k2 × r2) is established, the moment acting on the PCU 106 due to the inertial force in the vehicle longitudinal direction is zero.

  The in-vehicle structure 200 connected to the PCU 106 via a rib extending from the vibration-proof bushing also provides other advantages. FIG. 7 is a view when the PCU 106 is statically positioned, and a straight line V1 indicates the flange surface of the flange 114a of the inner cylinder 114 at that time. At this time, the flange surface of the flange 115a of the outer cylinder 115 is also parallel to the straight line V1. FIG. 8 is a diagram when the PCU 106 moves forward (X direction) due to vibration. In FIG. 8, the bracket 112 is deformed by the movement of the PCU 106. The straight line V1 in FIG. 8 is the same as the straight line V1 in FIG. 7. The straight line V2 in FIG. 8 is a straight line parallel to the straight line V1, and indicates the inclination of the flange surface of the outer cylinder 115 before the bracket 112 is deformed. Yes. The bracket 112 is deformed by the movement of the PCU 106. Due to the deformation of the bracket 112, the flange surface of the flange 115a of the outer cylinder 115 is inclined by an angle T2 as compared with that before the front bracket is deformed. On the other hand, the inner cylinder 114 is connected to the PCU 106 by a rib 114b, and the rib 114b is deformed as the PCU 106 moves. As a result, the flange surface of the flange 114a of the inner cylinder 114 is inclined by the angle T1 as compared with that before the front bracket is deformed. In the reference on-vehicle structure 200, the rib 114b extending from the flange 114a of the inner cylinder 114 is deformed. Therefore, the inclination (angle T1) of the flange surface of the flange 114a of the cylinder 114 is the inclination of the flange surface of the flange 115a of the outer cylinder 115 ( Near the angle T2). This means that when the PCU 106 receives an inertial force in the vehicle longitudinal direction, the torsion of the rubber bush 16 sandwiched between the inner cylinder 114 and the flange 114a and the outer cylinder 115 and the flange 115a is further reduced. To do. The reference vehicle-mounted structure 200 can more effectively suppress the twist generated in the rubber bush 16 when the PCU 106 receives an inertial force in the vehicle front-rear direction.

  The PCU 6 in the embodiment corresponds to an example of “power control device” in the claims. The front mount 10 according to the embodiment corresponds to an example of “first mount” in the claims, and the rear mount 20 corresponds to an example of “second mount”. The distance r1 in the vertical direction between the connection point between the front mount 10 and the PCU 6 and the center of gravity G corresponds to an example of a “first distance” in the claims, and the vertical distance between the connection point between the rear mount 20 and the PCU 6 and the center of gravity G. The direction distance r2 corresponds to an example of a “second distance” in the claims. The spring constant k1 in the vehicle front-rear direction of the front mount 10 at the connection point with the PCU 6 corresponds to an example of “first spring constant” in the claims. The spring constant k2 in the vehicle front-rear direction of the rear mount 20 at the connection point with the PCU 6 corresponds to an example of a “second spring constant” in the claims.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

2: Motor unit 3: Traveling motor 3a: Motor output shaft 6: PCU (power control device)
10: Front mount 10a, 20a: Connection location 12, 22: Bracket 13, 23: Anti-vibration bush 14, 24: Inner cylinder 14a, 15a, 24a, 25a: Flange 15, 25: Outer cylinder 16, 26: Rubber bush 20 : Rear mount 31, 32, 33, 34: Bolt 90: Hybrid vehicle 94: Engine room 97: Engine 100: In-vehicle structure 200: In-vehicle structure (reference)

Claims (2)

It is a vehicle-mounted structure of a power control device that controls the power supplied to the traveling motor,
The power control device is supported by the motor unit with a gap between the first and second mounts and the upper surface of the motor unit housing the traveling motor,
One end of the first mount is connected to one of a front part and a rear part of the casing of the power control device, and the other end is connected to the motor unit.
The second mount has one end connected to the other of the front part and the rear part, and the other end connected to the motor unit.
The height of the connection location (first connection location) between the housing and the first mount is lower than the height of the center of gravity of the power control device, and the connection location (second connection) between the housing and the second mount. The height of the location) is higher than the height of the center of gravity,
The vertical distance between the first connection location and the center of gravity is a first distance, and the vertical distance between the second connection location and the center of gravity is a second distance, and the first mount at the first connection location is the first distance. When the spring constant in the vehicle longitudinal direction is the first spring constant, and the spring constant in the vehicle longitudinal direction of the second mount at the second connection location is the second spring constant,
When the power control device receives an inertial force in the vehicle front-rear direction, a moment generated around an axis in the vehicle width direction of the center of gravity by the spring force received from the first and second mounts is the first and second. Of the first distance and the second distance, the spring constant of the shorter mount is set larger than the spring constant of the longer mount so that the moment when the spring constant is the same is smaller. In-vehicle structure. It is a vehicle-mounted structure of a power control device that controls the power supplied to the traveling motor,
The power control device is supported by the motor unit with a gap between the first and second mounts and the upper surface of the motor unit housing the traveling motor,
One end of the first mount is connected to one of the right side and the left side of the casing of the power control device, and the other end is connected to the motor unit.
The second mount has one end connected to the other of the right side and the left side, and the other end connected to the motor unit,
The height of the connection location (first connection location) between the housing and the first mount is lower than the height of the center of gravity of the power control device, and the connection location (second connection) between the housing and the second mount. The height of the location) is higher than the height of the center of gravity,
The vertical distance between the first connection location and the center of gravity is a first distance, and the vertical distance between the second connection location and the center of gravity is a second distance, and the first mount at the first connection location is the first distance. When the spring constant in the vehicle width direction is the first spring constant, and the spring constant in the vehicle width direction of the second mount at the second connection location is the second spring constant,
When the power control device receives an inertial force in the vehicle width direction, a moment generated around an axis in the vehicle longitudinal direction of the center of gravity by a spring force received from the first and second mounts is the first and second. Of the first distance and the second distance, the spring constant of the shorter mount is set larger than the spring constant of the longer mount so that the moment when the spring constant is the same is smaller. In-vehicle structure.

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