JP2009286303A - Body structure of electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a body structure of an electric vehicle allowing the reaction and vibration of motors and the reaction of a suspension to be handled separately, and advantageous when assembling the vehicle. <P>SOLUTION: The body structure is provided with a cradle frame 45 for supporting the right and left motors 35, 35 integrally to fix the relative position relationship of the motors 35, and the cradle frame 45 is mounted to a vehicle body lower face part through bush mounts 63, 67. The body structure is provided with a sub-frame 26 forming a body side mounting part of suspension arms 28 for supporting right and left rear wheels 27, 27, and mounted to a vehicle body bottom part. The sub-frame 26 and the cradle frame 45 are constituted independently and supported to the vehicle body separately. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  In the present invention, a pair of left and right motors whose rotating shafts are oriented substantially in the vehicle width direction and substantially coincide with each other are disposed at the center in the vehicle width direction at the rear of the vehicle body. The present invention relates to a vehicle body structure of an electric vehicle in which a rear wheel is connected to each other by a drive shaft, and the motor travels by driving left and right rear wheels via the drive shaft.

Conventionally, there is a structure disclosed in Patent Document 1 as a vehicle body structure of the electric vehicle of the above-described example.
In other words, a pair of left and right inboard type motors that drive the left and right front wheels independently is provided, and these motors are arranged so that their rotation shafts are substantially aligned in the vehicle width direction. The left and right front wheels, which are substantially coincident with each motor in the vehicle width direction, are driven by the motor to travel, and the left motor and the right motor are each in the form of a rectangular frame in plan view via a motor support member. A motor of an electric vehicle in which a base portion of a suspension arm that supports the left and right front wheels independently is supported by the subframe, and further, the subframe is attached to a vehicle body side member. Mount structure.
That is, the left and right motors and the base of the suspension arm are supported by the same subframe.

In this way, if the motor and suspension arm base are supported on the same subframe, the mass under the subframe becomes excessive, and complicated forces such as motor drive reaction force and wheel input, different frequencies, etc. Since this vibration acts on the same subframe, there is a problem that it is impossible to process the motor reaction force, vibration and suspension reaction force.
JP 2007-22276 A

  Therefore, the present invention provides a cradle frame that integrally supports the left and right motors that drive the rear wheels by fixing the relative positional relationship thereof, and the cradle frame is attached to the lower surface of the vehicle body via the bush mount, A sub-frame that is attached to the bottom of the vehicle body is formed as a vehicle body side attachment part for suspension arms that support the left and right rear wheels, and the sub-frame and the cradle frame are configured separately, and both of these are separately provided for the vehicle body. It is an object of the present invention to provide a vehicle body structure for an electric vehicle that can separately process the reaction force and vibration of the motor, and the reaction force of the suspension, which is advantageous when the vehicle is assembled.

In the vehicle body structure of the electric vehicle according to the present invention, a pair of left and right motors whose rotating shafts are substantially aligned in the vehicle width direction are arranged at the vehicle width direction central portion at the rear of the vehicle body. The left and right rear wheels that substantially coincide with the direction are respectively connected by drive shafts, and the motor drives the left and right rear wheels through the drive shafts to drive the vehicle body structure. A cradle frame that integrally supports a motor so as to fix the relative positional relationship of the motor is provided, and the suspension arm that supports the left and right rear wheels while the cradle frame is attached to the lower surface of the vehicle body via a bush mount A sub-frame that is attached to the bottom of the vehicle body is provided to form a vehicle body side attachment portion, and the sub-frame and the cradle frame are respectively connected Constituted by the body, is obtained by separately supported them both to the vehicle body.
According to the above configuration, since the cradle frame and the sub frame described above are configured separately, and both of them are separately supported by the vehicle body, the reaction force and vibration of the motor, and the reaction force of the suspension are separately determined. It can be processed and is advantageous when the vehicle is assembled.

In one embodiment of the present invention, the cradle frame holds the pair of left and right motors and is attached to the vehicle body via bush mounts at both positions in the front-rear direction of the motors. The motor is arranged so that the rotational axes of the motors substantially coincide with each other on a virtual line connecting the front and rear bush mounts in a side view.
According to the above configuration, the sub-frame and the cradle frame are separate from each other, and the rotation axis of the motor (in other words, the center of mass) substantially coincides with the imaginary line connecting the front and rear bush mounts. When the cradle frame vibrates due to the vibration reaction force of the motor, the vibration can be appropriately absorbed by the front and rear bush mounts without twisting the cradle frame.

In one embodiment of the present invention, the cradle frame holds a generator in front of the motor.
According to the above configuration, since the length of the cradle frame in the front-rear direction (that is, the front-rear length) is increased, the motor and the generator can be stably supported by a long span.

In one embodiment of the present invention, the bush mount is arranged such that the rear bush mount is positioned higher than the front bush mount.
According to the said structure, it becomes a mount arrangement | positioning suitable for the inertia principal-axis support of the pitching (pitching: vibration to which the front and back oppose up and down) direction, and the attachment corresponding to a body structure can be performed.

In one embodiment of the present invention, the rear portion of the cradle frame is provided with a plurality of projecting members extending upward from the cradle frame to the rear bush mount position, and the projecting members are disposed on the vehicle body via the rear bush mount. It is attached to.
According to the above configuration, the cradle frame and the protruding member can be formed separately, so that the cradle frame can be easily processed and formed.

  According to the present invention, the left and right motors for driving the rear wheels are provided with the cradle frame that integrally supports the relative positional relationship thereof fixed, and the cradle frame is attached to the lower surface of the vehicle body via the bush mount. A sub-frame that is attached to the bottom of the vehicle body to form a vehicle-body-side mounting portion for suspension arms that support the left and right rear wheels, and the sub-frame and the cradle frame are configured separately, and both of these are mounted on the vehicle body. Since they are supported separately, the reaction force and vibration of the motor and the reaction force of the suspension can be processed separately, which is advantageous in assembling the vehicle.

  For the purpose of being able to handle the reaction force and vibration of the motor, and the reaction force of the suspension separately, and to be advantageous when assembling the vehicle, the rotational shaft is substantially A pair of left and right motors that are substantially coincident in the width direction are disposed, and these motors and left and right rear wheels that substantially coincide in the vehicle width direction are respectively connected by drive shafts, and the motors connect the drive shafts. In a vehicle body structure of an electric vehicle that travels by driving left and right rear wheels, a cradle frame that integrally supports the left and right motors so as to fix the relative positional relationship of the motors is provided, and the cradle frame is a bush It is attached to the lower surface of the vehicle body via a mount, and forms a vehicle body side mounting portion of the suspension arm that supports the left and right rear wheels, The sub-frame to be attached provided, the sub-frame and the said cradle frame separately formed respectively, were achieved by construction that is supported separately both of them to the vehicle body.

An embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a side view showing the overall structure, FIG. 2 is a plan view thereof, FIG. 3 is an enlarged side view of the main part of FIG. 1, and FIG. 4 is an enlarged plan view of the main part of FIG. FIG. 5 is a bottom view of the main part.

1 to 5, a dash lower panel 3 is provided as a dash panel that partitions the engine room 1 and the vehicle compartment 2 in the front-rear direction, and the front of the vehicle compartment 2 separated by the dash lower panel 3 is connected to the engine room 1. It is set.
A floor panel 4 extending substantially horizontally toward the rear is connected to the lower portion of the above-described dash lower panel 3. The floor panel 4 forms the bottom surface of the passenger compartment 2, and a rear floor 6 is integrally or integrally connected to a rear portion of the floor panel 4 via a kick-up portion 5 rising upward. ing. The rear floor 6 is formed substantially horizontally.

  Further, a floor tunnel 7 (hereinafter referred to as a tunnel portion) having an upward convex shape (a shape projecting upward) extending in the front-rear direction of the vehicle is provided at the bottom center portion of the vehicle body. The tunnel portion 7 is the center of the vehicle body rigidity, and is integrally formed with the floor panel 4 between the dash lower panel 3 and the kick-up portion 5.

  2 is a plan view in which the floor panel 4, the kick-up portion 5, and the rear floor 6 are omitted for convenience of illustration, but as shown in FIGS. 1 and 2, the left and right sides of the tunnel portion 7 in the passenger compartment 2 are shown. Are provided with a driver seat 8 and a passenger seat 9 substantially in the vehicle width direction.

  The driver seat 8 described above includes a seat cushion 8C and a seat back 8B. Similarly, the passenger seat 9 described above also includes a seat cushion 9C and a seat back 9B. In this embodiment, since a right-hand drive vehicle is illustrated, the driver's seat 8 is disposed on the right side of the vehicle corresponding to the position of the steering wheel 10, but on the left side of the vehicle corresponding to the left-hand drive vehicle. You may comprise so that a sheet | seat may be arrange | positioned.

  As shown in FIGS. 1 and 2, the engine room 1 is provided with a pair of left and right front side frames 11 and 11 (vehicle body rigid members) extending from the dash lower panel 3 to the front of the vehicle, and the pair of front side frames 11. 11 are attached to the front ends of the front and rear crash bumps 12 and 12 as impact energy absorbing members, and a front bumper reinforcement 13 extending in the vehicle width direction is horizontally placed between the left and right crash cans 12 and 12.

Further, a recessed portion 3a that is recessed into the vehicle compartment 2 side is integrally formed at the center portion in the vehicle width direction of the above-described dash lower panel 3, and the center portion in the vehicle width direction of the engine room 1 corresponds to the recessed portion 3a. The engine 14 as an internal combustion engine is arranged (vertical arrangement).
The engine 14 has an engine output shaft 15 that is directed rearward in the vehicle front-rear direction, and includes an intake manifold 16 that communicates with an intake port of the cylinder head and an exhaust manifold 17 that communicates with an exhaust port of the cylinder head. . In the drawings, a reciprocating engine is illustrated as the engine 14, but a rotary engine may be used instead of the reciprocating engine.

  In front of the above-mentioned engine 14, a radiator unit 18 as a heat exchanger that cools engine cooling water (including coolant) using running wind is inclined so as to be slanted in front and rear. Yes. The radiator unit 18 is a unit in which a radiator main body and a cooling fan provided at the rear thereof are integrated.

  As shown in FIGS. 2 and 5, side sills 19 are bonded and fixed to the left and right sides of the floor panel 4. The side sill 19 is a vehicle body rigid member having a side sill closed section that joins a side sill inner and a side sill outer and extends in the front-rear direction of the vehicle. Note that. If necessary, a side sill reinforcement may be interposed between the side sill inner and the side sill outer.

  As shown in FIG. 5, a pair of left and right floor frames 20 and 20 are attached to the lower surface of the above-described floor panel 4 at an intermediate portion in the vehicle width direction between the tunnel portion 7 and the side sill 19. The floor frame 20 is formed in an inverted hat-shaped cross section, and a closed cross section extending in the front-rear direction of the vehicle is formed between the floor frame 20 and the lower surface of the floor panel 4. The floor frame 20 is a rigid body member that is continuous with the pair of left and right front side frames 11 and 11 in the front-rear direction of the vehicle in a plan view or a bottom view.

  Further, as shown in FIG. 5, a pair of left and right tunnel braces 21 and 21 extending in the front-rear direction of the vehicle are provided between the lower portion of the tunnel part 7 and the floor panel 4 at the rear part in the front-rear direction of the tunnel part 7. Closed sections 22 and 22 (see FIG. 10) extending in the vehicle front-rear direction are formed between the tunnel braces 21 and 21 and the lower portion of the tunnel portion 7 and the floor panel 4, respectively. The tunnel rigidity is improved.

  As shown in FIGS. 1, 2, and 5, on both lower sides of the rear floor 6 described above, rear side frames 23 and 23 (vehicle body rigid members) having a reverse hat shape extending in the longitudinal direction of the vehicle are provided. A closed cross section extending in the front-rear direction of the vehicle is formed between the frame 23 and the rear floor 6. Further, the front portions of the left and right rear side frames 23, 23 extend forward to a position where they overlap with the left and right side sills 19, 19 in the longitudinal direction of the vehicle.

  As shown in FIGS. 2 and 3, a rear cross member 24 (so-called No. 4 cross member) extending in the vehicle width direction is provided between the pair of left and right rear side frames 23, 23, and is formed in a reverse hat shape in cross section. A closed cross section 25 extending in the vehicle width direction is formed between the rear cross member 24 and the rear floor 6 so as to improve the rear vehicle body rigidity.

Further, as shown in a bottom view in FIG. 5, a suspension cross member 26 is attached to the lower part of the pair of left and right rear side frames 23, 23. The suspension cross member 26 includes a front cross member 26F extending in the vehicle width direction, a rear cross member 26R extending in the vehicle width direction, and left and right side cross members 26S, 26S extending in the vehicle front-rear direction. The left and right rear wheels 27 are suspended independently from the suspension cross member 26 via a plurality of suspension arms.
Although it is actually a multi-link type suspension, in the drawing, for convenience of illustration, only the front and rear lower arms 28 are shown, and other elements such as an upper arm and a toe control link are not shown.

  The above-described suspension cross member 26 (subframe) forms a vehicle body side mounting portion of the lower arms 28, 28 as suspension arms for supporting the left and right rear wheels 27, 27, and is the bottom of the vehicle body, specifically, the left and right rear side frames. 23 and 23 are attached to the bottom of each through a rubber mount.

  By the way, as shown in FIGS. 1 to 5, it is located behind the driver seat 8 and the passenger seat 9 and in front of the rear wheel 27 described above, and below the bottom of the passenger compartment 2 (that is, the rear floor). The generator 30 is arranged in the vehicle width direction central portion of the vehicle outer side 6.

The generator 30 is configured such that the main shaft on the rotor side in the generator 30 rotates through a universal joint 31, a transfer shaft 32, a universal joint 33, and a coupling 34 on the engine output shaft 15 shown in FIGS. The transfer shaft 32 is connected to the tunnel portion 7 so as to extend in the front-rear direction of the vehicle.
That is, the above-described generator 30 is driven by the engine 14 to generate power.

Further, the motors 35 and 35 that are rotated by the electric power output from the above-described generator 30 are arranged at the center in the vehicle width direction at the rear of the vehicle body. As shown in FIGS. 3 to 5, in this embodiment, the motors 35, 35 are located in the vehicle width direction center portion of the lower outside (the vehicle outer side of the rear floor 6) at the bottom of the passenger compartment 2 and approach the generator 30. The motor 35 is arranged on a virtual coaxial axis in the vehicle width direction as shown in FIGS. 4 and 5 at the rear position thereof and at a position substantially coincident with the rear wheels 27, 27 in a side view. 2 are a total of two independent motors arranged on the left and right.
In other words, the pair of left and right motors 35, 35 are arranged such that their rotation shafts 35c (see FIG. 3) are substantially aligned with each other in the substantially vehicle width direction.

  In short, a total of two motors 35, 35 comprising independent motors are juxtaposed on the left and right sides so as to substantially coincide with the rear wheels 27, 27 outside the rear floor 6 and behind the above-described generator 30. The rotating shafts 35c (see FIG. 3) of the left and right motors 35, 35 are arranged substantially on the virtual coaxial line in the vehicle width direction.

The reduction gear units 36 and 36 each including a planetary gear mechanism including a sun gear, a carrier, and a ring gear are integrally attached to the outside of the left and right motors 35 and 35 in the vehicle width direction. .
The motor 35 and the rear wheel 27, more specifically, a ring gear (not shown) in the gear unit 36 and the rear wheel 27 are connected by a pair of left and right drive shafts 37, 37 extending in the vehicle width direction. The wheels 27 and 27 are configured to be driven by the rotational force of the left and right motors 35 and 35.

  That is, the left and right motors 35 and 35 are connected to the left and right rear wheels 27 and 27 that substantially coincide with the vehicle width direction by the drive shafts 37 and 37, respectively. The left and right rear wheels 27, 27 are driven via a drive 37.

  6 (a) is a plan view of the present embodiment schematically showing the configuration of FIG. 4, FIGS. 6 (b) and 6 (c) are comparative examples, and FIG. 6 (b) shows a generator. And the motor are connected in a straight line in the front-rear direction of the vehicle, and a differential output is made to the left and right drive shafts 37, 37 via a rear differential device 38. In FIG. 6C, a rear differential device 38 is disposed behind the generator, and a motor is disposed laterally behind the generator. The left and right drive shafts 37, 37 are disposed via the rear differential device 38. Differential output.

  The comparative example shown in FIG. 6B has a drawback that the length L3 (so-called longitudinal length) in the vehicle front-rear direction from the front end of the generator to the rear end of the rear differential device 38 becomes longer.

  In the comparative example shown in FIG. 6C, the length L2 in the vehicle front-rear direction (so-called front-rear length) from the front end of the generator to the rear end of the motor is slightly shortened, but the weight balance becomes asymmetric. Is not preferable because left and right becomes uneven.

  On the other hand, in the embodiment shown in FIG. 6A, the left and right independent motors 35, 35 are arranged on the virtual coaxial line in the vehicle width direction. The length L1 (so-called longitudinal length) of the vehicle longitudinal direction of the mechanism 30 including the machine 30 and the motors 35, 35) can be set to a minimum, and the generator 30 and the left and right motors 35, As shown in the figure, it is effective because heavy objects can be arranged symmetrically as shown in the figure, and the length of the drive shaft 37 in the vehicle width direction is also minimized. Can be set. In addition, it is possible to stably support the left and right independent motors 35, 35 arranged on the virtual coaxial axis with a wide width W in the vehicle width direction.

  On the other hand, as shown in FIG. 3 and FIG. 4, an inverter unit 40 (a power control unit, which agrees with the PCU) for converting the electric power of the generator 30 for driving the motor is provided. As shown in FIG. 12, the inverter unit 40 includes a control unit 41, a power module 42, and voltage smoothing capacitors 43, 43. The inverter unit 40 is shown in FIGS. 3, 4, and 12. The left and right independent motors 35, 35 are disposed in a dead space between the front of the left and right motors 35 and the upper left and right sides of the generator 30. With this structure, the capacitor 43 has a sufficient capacity (that is, a capacitance). The above-described inverter unit 40 is cooled by a water cooling method.

As shown in FIGS. 1, 2, 3, and 5, fuel tanks 44 are disposed on the left and right of the above-described generator 30 in front of the left and right independent motors 35, 35. As shown in the bottom view of FIG. 5, the fuel tank 44 includes a left tank portion 44a, a right tank portion 44b, and a communication portion 44c that connects the upper portions of both tank portions 44a and 44b in the vehicle width direction. The dead space on the upper side, the right side, and the left side of the generator 30 is effectively used, and the weight balance of the generator 30 is equalized on the left and right.
Further, as shown in FIG. 5, since the rear side frames 23 and 23 as vehicle body rigid members are located outside the left and right tank portions 44a and 44b of the fuel tank 44, the fuel tank 44 is located on the side. It is also effective against crashes.

  By the way, the generator 30, the inverter unit 40, and the left and right motors 35, 35 are integrally supported by a cradle frame 45 having a substantially rectangular frame shape in plan view as shown in a plan view in FIG. The structure for supporting each element 30, 40, 35 by the cradle frame 45 will be described in detail below.

  7 is a perspective view of the cradle frame 45, FIG. 8 is an enlarged view of the main part of FIG. 3, FIG. 9 is an enlarged view of the main part of FIG. 4, and the cradle frame 45 is shown in FIGS. As described above, the front side portion 45a extending in the vehicle width direction at the front portion, the rear side portion 45b extending in the vehicle width direction at the rear portion, the side portion 45c extending in the substantially front-rear direction of the vehicle at the left side portion, and the vehicle at the right side portion. The side part 45d extending in the front-rear direction is formed by processing a metal round pipe (rigid pipe) into a substantially rectangular frame shape in plan view.

  10 is a cross-sectional view taken along line AA in FIG. 4, FIG. 11 is a cross-sectional view taken along line BB in FIG. 4, and FIGS. 12, 13, and 14 are taken along line CC in FIG. Sectional drawing (however, FIG.13, FIG.14 shows the other Example of an inverter unit support structure), FIG.15 is DD sectional view taken on the line of FIG.

First, the support structure of the generator 30 will be described with reference to FIGS. 3, 8, 9, and 11.
Mounting flanges 30a and 30a are integrally formed on both the left and right portions of the generator 30, and the left and right side portions 45c and 45d of the cradle frame 45 are welded to the outer sides of the cradle frame 45 corresponding to the left and right mounting flanges 30a and 30a. The flanges 46, 46 are formed integrally with each other.

  Then, mounting flanges 30a, 30a of the generator 30 are mounted on the flanges 46, 46 of the cradle frame 45 described above, and both the flanges 46, 30a are fastened by using a plurality of mounting members 47 such as bolts and nuts. The generator 30 is attached to the cradle frame 45. In this case, the lower end side of the generator 30 is positioned between the left and right side portions 45c and 45d of the cradle frame 45, thereby improving the space efficiency. I am trying.

Next, the support structure of the inverter unit 40 will be described with reference to FIGS.
Corresponding to the left and right legs 40a, 40b of the inverter unit 40 formed in a bowl shape, the left and right side portions 45c, 45d of the cradle frame 45 are provided with inverted L-shaped mounting brackets 48, 48 extending upward. Are integrally provided, and both left and right leg portions 40a, 40b of the inverter unit 40 are fastened and fixed to the both mounting brackets 48, 48 by using mounting members 49, 49 such as bolts.

  The mounting brackets 48, 48 described above have reinforcing ribs 48a, 48a. With this structure, the inverter unit 40 can be stably supported on the cradle frame 45.

  Instead of the inverter unit support structure shown in FIG. 12, the support structure shown in FIG. 13 or FIG. 14 may be adopted.

The support structure of the inverter unit 40 shown in FIG. 13 extends in the vehicle width direction between the left and right mounting brackets 48 and 48 and the bottom surfaces of both leg portions 40a and 40b of the inverter unit 40 in addition to the configuration of FIG. A rigid plate member 50 (so-called plate) for connecting the left and right mounting brackets 48, 48 is provided, and the mounting bracket 49 and the rigid plate member 50 are attached to the bottom surfaces of the left and right leg portions 40a, 40b of the inverter unit 40 by the mounting member 49. And fastened together.
If comprised in this way, the support rigidity of the inverter unit 40 can be improved.

The support structure of the inverter unit 40 shown in FIG. 14 is such that the brackets 51, 51 are integrated with the left and right side portions 45 c, 45 d of the cradle frame 45 corresponding to the left and right legs 40 a, 40 b of the inverter unit 40. Projected to
The bracket 51 described above is attached to the side portions 45c and 45d of the cradle frame 45 by welding with an arc-shaped cross section, and extends upward from the mounting seat 51a toward the bottom surfaces of both legs 40a and 40b of the inverter unit 40. And a horn-shaped projecting member 51b having a continuous U-shaped cross section.

  Then, by fixing the upper portions of the protruding members 51b, 51b of the pair of left and right brackets 51, 51 to the left and right leg portions 40a, 40b of the inverter unit 40 by using mounting members 49, 49 such as bolts, The inverter unit 40 is stably supported with respect to the cradle frame 45.

Next, a support structure for the pair of left and right motors 35 and 35 will be described with reference to FIGS. 3, 7 to 9, and 15.
The cradle frame 45 described above integrally supports the pair of left and right motors 35 and 35 so as to fix the relative positional relationship between the motors 35 and 35.
As shown in FIGS. 3, 8, 9, and 15, flanges 35 a and 35 a are integrally formed at both lower front and rear positions of the left and right motors 35 and 35, respectively. On the other hand, as shown in FIGS. 7 and 15, there are a substantially U-shaped holding portion 52 a for holding the side portion 45 c and a mounting seat 52 b at both front and rear sides of the left side portion 45 c of the cradle frame 45. , 52c and front and rear mounting brackets 52, 52 are provided.

Further, as shown in FIGS. 7 and 15, there are a substantially U-shaped holding portion 53 a for holding the side portion 45 d and a mounting seat 53 b at both front and rear sides of the right side portion 45 d of the cradle frame 45. , 53c and front and rear mounting brackets 53, 53 are provided.
Then, as shown in FIG. 15, in the state where the side portion 45c of the cradle frame 45 is held from below by the holding portion 52a of the mounting bracket 52 on the left side and both front and rear positions, the mounting seats 52b and 52c of the mounting bracket 52 are provided. Are fastened and fixed to the flange 35a of the left motor 35 by using a plurality of bolts (fastening members) 54.

In the state where the side portion 45d on the right side of the cradle frame 45 is held from below by the holding portion 53a of the mounting bracket 53 on the other right side and both front and rear positions, the mounting seat 53b of the mounting bracket 53 is bolted (fastening member). ) 55 and 55 are fastened and fixed so as to straddle the flange 35a of the right motor 35 and the flange 35a of the left motor 35.
In this way, using a total of four mounting brackets 52, 52, 53, 53, a pair of left and right motors 35, 35 are fixed to the cradle frame 45, and the relative positional relationship between these motors 35, 35 is fixed. It is supported integrally. Here, the left and right mounting brackets 52 and 53 may be integrally formed, and the pair of left and right motors 35 and 35 may be integrally mounted and supported on the cradle frame 45 by a total of two brackets at both the front and rear positions. Good.

  Further, as shown in a front view in FIG. 15, the flange 35a of the motor 35 on the right side of the vehicle is formed in other parts, leaving a distance L0 in the vehicle width direction from the right end of the motor 35. Corresponding to L0, an exhaust pipe installation space 56 is formed in the lower part of the right motor 35.

Further, as shown in a side view in FIGS. 3 and 8 and in a perspective view in FIG. 7, the side portions 45c and 45d of the cradle frame 45 between the front and rear mounting brackets 52 and 52 and 53 and 53 are provided as motors. It is formed in a curved shape that protrudes downward to correspond to the lower shape of 35.
In this manner, the generator 30, the inverter unit 40, and the left and right independent motors 35, 35 are integrally attached and supported on the cradle frame 45 described above.

Next, a structure for attaching and supporting the cradle frame 45 in which these elements 30, 40, 35, and 35 are assembled to the vehicle body will be described.
As shown in FIGS. 7, 8, and 9, a pair of left and right brackets 57, 57 extending forward from the corner portion are attached to the front corner portion of the cradle frame 45, and each of these brackets 57, 57 is attached to each bracket 57, 57. Bolts 58 and 58 are integrally provided as support shafts protruding forward.

  Further, as shown in FIGS. 7 to 9 and FIG. 15, a corner portion on the rear side of the cradle frame 45 has a pair of left and right projecting members 59, 59 (upward extending from the corner portion to a bush mount 67 position described later). A so-called corner portion is attached, and these projecting members 59, 59 are integrally provided with bolts 60, 60 as pivots projecting rearward. The above-described protruding member 59 is formed of a rigid member having a U-shaped cross section as indicated by a dotted line in FIG.

On the other hand, as shown in FIGS. 3 to 5, tunnel cross members 61 (so-called mounts) for connecting the pair of left and right tunnel braces 21, 21 in the vehicle width direction are formed on the lower surfaces of the pair of left and right tunnel braces 21, 21. Member).
As shown in FIG. 10, this tunnel cross member 61 is stretched in the vehicle width direction between a pair of left and right tunnel braces 21, 21 using a mounting member 62 such as a bolt or a nut. The front side of the cradle frame 45 is elastically supported by the tunnel cross member 61 via a plurality of bush mounts 63 and 63 as shown in FIGS. 3 to 5 and 8 to 10.

  Here, as shown in FIGS. 8, 9, and 16, the bush mount 63 described above includes an outer cylinder 63a, a sleeve 63b, and a rubber member 63c interposed between the both 63a and 63b. The bolt 58 provided on the front side of the cradle frame 45 through the bracket 57 passes through the sleeve 63b of the bush mount 63, and the nut 64 is tightened to the threaded portion of the bolt 58 protruding forward from the sleeve 63b. The front side of the cradle frame 45 is supported by the tunnel cross member 61 via a plurality of bush mounts 63, 63.

Further, as shown in FIGS. 3 to 5 and FIG. 15, a bracket 66 (so-called mount) is provided on the lower surface of the rear cross member 24 (so-called No. 4 cross-member) by using mounting members 65 such as bolts and nuts. A pair of left and right bush mounts 67, 67 are attached to the bracket 66 as shown in FIG. Similar to the bush mount 63 on the tunnel cross member 61 side, these bush mounts 67, 67 are configured to have an outer cylinder 67 a, a sleeve 67 b, and a rubber member 67 c, and a protruding member 59 on the rear side of the cradle frame 45. The bolt 60 provided via the bushing 67 passes through the sleeve 67b of the bush mount 67, and the nut 64 is fastened to the threaded portion of the bolt 60 protruding rearward from the sleeve 67b. Are supported by the rear cross member 24 via bush mounts 67, 67.
That is, the cradle frame 45 in which the generator 30, the inverter unit 40, and the left and right motors 35 and 35 are assembled is attached to the lower surface of the vehicle body via a plurality of front and rear bush mounts 63, 63, 67, and 67. ing.

In addition, as shown in the bottom view in FIG. 5, the suspension cross member 26 and the cradle frame 45 described above are configured separately, and these both 26 and 45 are supported separately from the vehicle body. Yes.
That is, the suspension cross member 26 is supported on the bottom of the rear side frame 23, while the cradle frame 45 is connected to the tunnel cross member 61 as the lower surface of the vehicle body and the rear via a plurality of bush mounts 63, 63, 67, 67. It is supported by the cross member 24.

  With this configuration, the cradle frame 45 that supports the motors 35 and 35, and the suspension cross member 26 (subframe) that constitutes the vehicle body side attachment portion of the suspension arm, the reaction force and vibration of the motor 35, Although the reaction force of the suspension is inputted, these reaction force and vibration can be processed separately.

  Further, as shown in FIGS. 8 and 9, the cradle frame 45 described above holds a pair of left and right motors 35, 35, and bush mounts 63, 63, 67, As shown in FIG. 8, the bush mounts 63, 67 are imaginary connecting the front bush mounts 63, 63 and the rear bush mounts 67, 67 as viewed from the side of the vehicle. The rotation axis 35c of the motor 35 described above is arranged on the line α so as to substantially coincide. With this configuration, when the cradle frame 45 swings due to the vibration reaction force of the motor 35, the cradle frame 45 can be properly absorbed by the front and rear bush mounts 63 and 67 without causing torsion. .

  17 shows an imaginary line α and a mass connecting the support points X and Y with respect to the vehicle body in the configuration of the embodiment shown in FIG. 8 (see a in FIG. 17) and the configuration of the comparative example (see b in FIG. 17). Difference in force acting on the support points X and Y when there is no offset amount (corresponding to the motor 35) (FIG. 17a) and when there is an offset amount (FIG. 17b). It is explanatory drawing which shows.

As shown in FIG. 17 (b), when there is an offset amount, the driving reaction force T causes the support points X and Y to move in the front-rear direction indicated by the dotted arrows in addition to the vertical force indicated by the solid arrows. However, as shown in FIG. 17A, when the offset amount is zero, the force acting on the support points X and Y by the driving reaction force T is the vertical direction indicated by the solid line arrows. Only power.
For this reason, as shown in FIG. 8, when the rotating shaft 35c of the motor 35 substantially coincides with the imaginary line α, the driving reaction force of the motor 35 is appropriately absorbed by the front and rear bush mounts 63 and 67. It is something that can be done.

Further, as shown in FIGS. 8 and 9, the cradle frame 45 holds the generator 30 in front of the pair of left and right motors 35, 35. The front and rear lengths required to hold the unit integrally are set, whereby the length of the cradle frame 45 in the front and rear direction is expanded, and the motor 35 and the generator 30 are stably supported by a long span. Can do. The pair of motors 35 and 35 and the generator 30 are arranged in a substantially T shape in plan view as shown in FIG.
In addition, as shown in FIGS. 3 and 8, the above-described bush mounts 63 and 67 are arranged such that the rear bush mount 67 is positioned higher than the front bush mount 63. The frame 45 is configured to secure a mount arrangement suitable for supporting the inertial main axis β (see FIG. 9) in the pitching direction.

  Further, since the height positions of the front and rear bush mounts 63 and 67 are made different as described above, it is possible to perform appropriate attachment corresponding to the body structure. That is, the bottom of the rear cross member 24 at the bottom of the rear floor 6 on which the rear bush mount 67 is disposed is lower than the height of the kick-up portion 5 in the vertical direction with respect to the lower portion of the tunnel brace 21 on which the front bush mount 63 is disposed. It is set at a high position by a substantially equal height, and appropriate attachment to such a body structure can be performed.

  Further, as shown in FIG. 7, the rear portion of the cradle frame 45 has a plurality of projecting members 59 and 59 (a pair of left and right projecting members 59) extending upward from the cradle frame 45 to the positions of the rear bush mounts 67 and 67. 59), and the plurality of projecting members 59, 59 are attached to the vehicle body via bush mounts 67, 67 at the rear. If comprised in this way, since the cradle frame 45 and the protrusion member 59 can each be formed separately, the process and formation of the cradle frame 45 become easy.

  Instead of the structure shown in FIG. 7, the structure shown in FIG. 18 may be adopted. That is, in FIG. 18, in addition to the configuration of FIG. 7, a cross member 59 </ b> A that couples both the left and right protruding members 59, 59 in the vehicle width direction is provided at the middle position in the vertical direction. Thus, the rigidity of the entire cradle frame 45 including the projecting member 59 is improved. In FIG. 18, the same parts as those in FIG. 7 are denoted by the same reference numerals, and detailed description thereof is omitted.

Next, the arrangement structure of the exhaust system will be described.
As shown in a plan view in FIG. 2, a front exhaust pipe 70 is connected to a downstream portion of the exhaust manifold portion of the exhaust manifold 17 connected to the exhaust port of the engine 14, and a downstream end of the front exhaust pipe 70 is connected to a downstream end of the exhaust manifold 17. As shown in FIGS. 1 and 2, an exhaust gas purifying catalyst 71 is connected.

As shown in FIGS. 1 and 2, the above-described catalyst 71 is disposed adjacent to the transfer shaft 32 in the tunnel portion 7, and the catalyst 71 is located as close to the engine 14 as possible. It is arranged.
An exhaust pipe 72 is connected downstream of the above-described catalyst 71. As shown in FIGS. 1 to 5 and 10, the exhaust pipe 72 extends to the rear of the vehicle through the tunnel portion 7, and the left and right motors 35, 35 are disposed as shown in FIG. 15. The main silencer 74 is connected to the downstream end of the exhaust pipe 72 via a joint flange 73 through the exhaust pipe arrangement space 56 formed in the lower part of the right motor 35 and further to the rear of the vehicle. Tail pipes 75 and 75 are connected to the left and right sides of the main silencer 74.

Next, a harness arrangement structure will be described with reference to FIG.
FIG. 19 is an enlarged plan view of the main part of FIG. 4, and the generator 30, the inverter unit 40, and the left and right motors 35, 35 are provided with connectors 80, 81, 82, 83, 84, respectively. A connector 85 provided at 30 is connected to a harness 85, and the harness 85 is used to input generator output power to the inverter unit 40.

  Further, the left and right connectors 81 and 82 on the inverter unit 40 side and the connectors 83 and 84 of the left and right motors 35 and 35 are connected by harnesses 86 and 87, and the inverter unit 40 converts the motor drive. It is configured to supply electric power to the left and right motors 35, 35.

  In FIGS. 1 and 2, 90 is a front wheel, 91 is a bonnet, 92 is a front window glass, 93 is a roof portion, 94 is a rear window glass, 95 is a trunk lid, 96 is an instrument panel, and 97 is a hinge pillar. In the figure, arrow F indicates the front of the vehicle, and arrow R indicates the rear of the vehicle.

  In the electric vehicle configured as described above, the rotational force of the engine 14 is transmitted to the transfer shaft 32 via the engine output shaft 15 after the rotational unevenness is reduced by the inertial force of the flywheel (not shown). Since the generator 30 is driven by the transfer shaft 32, the generator 30 generates electric power, and the electric power is converted into motor drive by the inverter unit 40, and then the left and right motors 35, 35.

  When the left and right motors 35, 35 rotate, the output of the motor rotation shaft 35 c is input to a sun gear (not shown) in the gear unit 36, and then the rotational speed is reduced to about 1/7 by the planetary gear mechanism. Since it is output from the inner ring gear, the driving force is transmitted to the left and right rear wheels 27, 27 via the left and right drive shafts 37, 37.

In short, in the vehicle body structure of the electric vehicle having the above-described configuration, a pair of left and right motors 35, 35 in which the rotation shaft 35c is substantially aligned in the vehicle width direction are disposed at the vehicle width direction center portion at the rear of the vehicle body. These motors are connected to left and right rear wheels 27, 27 substantially in the vehicle width direction by drive shafts 37, 37, respectively, and the motors 35, 35 are connected to the left and right rear wheels via the drive shafts 37, 37. A vehicle body structure of an electric vehicle that travels by driving wheels 27, 27, and includes a cradle frame 45 that integrally supports the left and right motors 35, 35 so as to fix the relative positional relationship between the motors 35, 35. The cradle frame 45 is attached to the lower surface of the vehicle body via bush mounts 63 and 67, while the suspension arm supporting the left and right rear wheels 27 and 27 is provided. A sub-frame (see the suspension cross member 26) that is attached to the bottom of the vehicle body as a vehicle body-side attachment portion of a frame (see the lower arm 28) is provided, and the sub-frame (see the suspension cross member 26) and the cradle frame 45 are connected to each other. Each of them is configured as a separate body, and both of them are supported separately on the vehicle body (see FIGS. 2 and 5).

  According to this configuration, the cradle frame 45 and the sub-frame (see the suspension cross member 26) described above are configured separately, and both the 26 and 45 are separately supported by the vehicle body. In addition, vibrations and suspension reaction forces can be processed separately, which is also advantageous when the vehicle is assembled.

Further, the cradle frame 45 holds the pair of left and right motors 35 and 35 and is attached to the vehicle body via bush mounts 63 and 67 at both front and rear positions of the motors 35 and 35, respectively. 63 and 67 are arranged so that the rotation shaft 35c of the motor 35 substantially coincides with a virtual line α (see FIG. 8) connecting the front and rear bush mounts 63 and 67 in a side view of the vehicle (FIG. 8). reference).
According to this configuration, the sub-frame (see the suspension cross member 26) and the cradle frame 45 are separate from each other, and the rotation shaft 35c of the motor 35 is placed on the virtual line α connecting the front and rear bush mounts 63 and 67. Since the cradle frame 45 vibrates in response to the vibration reaction force of the motor 35, the front and rear bush mounts 63, 67 are not twisted without causing the cradle frame 45 to twist. Thus, vibration can be appropriately absorbed.

The cradle frame 45 holds the generator 30 in front of the motors 35 (see FIG. 9).
According to this configuration, since the length of the cradle frame 45 in the front-rear direction (that is, the front-rear length) is enlarged, the motor 35 and the generator 30 can be stably supported by a long span.

In addition, the bush mounts 63 and 67 are arranged such that the rear bush mount 67 is positioned higher than the front bush mount 63 (see FIGS. 3 and 8).
According to this configuration, the cradle frame 45 has a mount arrangement suitable for supporting the inertial main shaft β (see FIG. 9) in the pitching direction (pitching: vibration in which the front and back are reversed up and down), and is mounted according to the body structure. be able to.

Furthermore, a plurality of projecting members 59, 59 extending upward from the cradle frame 45 to the position of the rear bush mount 67 are provided at the rear portion of the cradle frame 45, and the projecting members 59, 59 serve as the rear bush mount 67, It is attached to the vehicle body (see rear cross member 24) via 67 (see FIGS. 3 and 7).
According to this configuration, the cradle frame 45 and the projecting members 59 and 59 can be formed separately, so that the cradle frame 45 can be easily processed and formed.

In the correspondence between the configuration of the present invention and the above-described embodiment,
The suspension arms of the present invention correspond to the lower arm 28 of the embodiment,
Similarly,
The subframe corresponds to the suspension cross member 26,
The present invention is not limited to the configuration of the above-described embodiment.

The side view which shows the vehicle body structure of the electric vehicle of this invention Plan view showing the body structure of an electric vehicle 1 is an enlarged side view of the main part of FIG. The main part enlarged plan view of FIG. Bottom view showing the body structure of an electric vehicle It is the schematic which shows the arrangement structure of a generator and a motor, (a) is a top view of a present Example, (b) (c) is a top view of a comparative example. Cradle frame perspective view 3 is an enlarged side view of the main part of FIG. 4 is an enlarged plan view of the main part of FIG. AA sectional view taken along line AA in FIG. 4 is a cross-sectional view taken along line BB in FIG. CC sectional view taken along the line CC in FIG. Front view showing another embodiment of the inverter unit support structure Front view showing still another embodiment of the inverter unit support structure DD sectional view taken along line D-D in FIG. Exploded perspective view showing support structure with bush mount (A) (b) is explanatory drawing which shows the difference of the acting force to a support point by the presence or absence of offset amount. A perspective view showing another embodiment of the cradle frame peripheral structure Partial enlarged plan view showing the arrangement structure of the harness

Explanation of symbols

26 ... Suspension cross member (subframe)
27 ... Rear wheel 28 ... Lower arm (suspension arm)
30 ... Generator 35 ... Motor 35c ... Rotating shaft 37 ... Drive shaft 45 ... Cradle frame 59 ... Protruding members 63, 67 ... Bush mount

Claims (5)

A pair of left and right motors whose rotating shafts are substantially aligned in the vehicle width direction are arranged at the center in the vehicle width direction at the rear of the vehicle body,
Each of these motors and the left and right rear wheels that substantially coincide with the vehicle width direction are connected by drive shafts, respectively.
The electric vehicle has a vehicle body structure that travels by driving left and right rear wheels via the drive shaft,
A cradle frame that integrally supports the left and right motors so as to fix the relative positional relationship between the motors is provided,
While the cradle frame is attached to the lower surface of the vehicle body via a bush mount,
Provide a sub-frame that is attached to the bottom of the vehicle body to form a vehicle body side mounting portion of the suspension arms that support the left and right rear wheels,
A vehicle body structure for an electric vehicle, wherein the sub-frame and the cradle frame are configured separately, and both of them are separately supported by the vehicle body. The cradle frame holds the pair of left and right motors and is attached to the vehicle body via bush mounts at both positions in the front-rear direction of the motors,
The electric vehicle body structure according to claim 1, wherein the bush mount is disposed such that a rotation axis of the motor substantially coincides with a virtual line connecting the front and rear bush mounts in a side view of the vehicle. The electric vehicle body structure according to claim 2, wherein the cradle frame holds a generator in front of the motor. The electric vehicle body structure according to claim 3, wherein the bush mount is disposed such that a rear bush mount is positioned higher than a front bush mount. The rear part of the cradle frame is provided with a plurality of projecting members extending upward from the cradle frame to the rear bush mount position,
The electric vehicle body structure according to claim 4, wherein the projecting member is attached to the vehicle body via a rear bush mount.

Images