JP7647197B2 - In-wheel motor vehicle - Google Patents

Description

This invention relates to a vehicle equipped with a motor inside the front or rear wheels.

Patent Document 1 describes a vehicle in which an in-wheel motor housed in a drive wheel is supported by a lower arm and an upper arm. This vehicle connects an electric unit provided on the vehicle body to the in-wheel motor via a harness, and is configured so that if the vehicle derails during a collision or other event, the connection between the electric unit and the harness breaks. In other words, the strength of the connection between the electric unit and the harness is configured to be lower than the strength of the connection between the in-wheel motor and the harness.

JP 2016-159814 A

When an electric unit provided on a vehicle body and an in-wheel motor are connected by a harness as described in Patent Document 1, if the in-wheel motor vibrates when traveling on an uneven road surface, or if the in-wheel motor tilts relative to the vehicle body during cornering and the harness bends, a load is applied to the connection between the electric unit and the harness. Therefore, if the strength of the connection between the electric unit and the harness is reduced as described in Patent Document 1, robustness against the vibration of the in-wheel motor and bending of the harness may decrease. Conversely, if the strength of the connection between the harness and the in-wheel motor is increased, the connection will become larger, which may increase the unsprung load. Furthermore, if a mechanism is added to ensure the connection state of the connection between the electric unit and the harness even when the in-wheel motor vibrates or the harness bends, the configuration near the connection may become larger.

This invention was made with a focus on the above technical problems, and aims to provide an in-wheel motor vehicle that can reduce the load acting on the cable when a drive wheel equipped with an in-wheel motor comes off while maintaining the strength of the cable and its connection part that connects the electric unit provided on the vehicle body to the in-wheel motor.

In order to achieve the above object, the present invention provides an in-wheel motor vehicle comprising a drive wheel, an in-wheel motor provided inside the drive wheel and outputting torque to the drive wheel, a power source provided on a vehicle body, and a cable electrically connecting the power source and the in-wheel motor , the in-wheel motor further comprising a suspension whose upper end is held by the vehicle body and supporting the in-wheel motor so that it can move up and down , and a connecting member connected to the vehicle body and the in-wheel motor, or connected to a power source side connector that attaches the cable to the power source and the in-wheel motor, or connected to a motor side connector that attaches the cable to the in-wheel motor and the vehicle body, the connecting member being provided inside the suspension in the fore-and-aft direction of the vehicle body and being formed to be bendable, the length of the connecting member being longer than the shortest distance between an attachment portion of the connecting member on the vehicle body side and an attachment portion of the connecting member on the in-wheel motor side when the suspension is displaced to its maximum and the drive wheel is steered to its maximum, and being shorter than the cable.

According to this invention, the vehicle body and the in-wheel motor, or the power supply connector and the in-wheel motor, or the motor connector and the vehicle body are connected by a connecting member. The connecting member is formed shorter than the cable connecting the power supply and the in-wheel motor. Therefore, even if the wheel derails, the distance between the derailed drive wheel and the vehicle body, or the distance between the power supply connector and the in-wheel motor, or the distance between the motor connector and the vehicle body can be prevented from exceeding the full length of the connecting member. As a result, it is possible to prevent a tensile load from acting on the cable when the wheel derails, and to prevent the cable from breaking. In other words, the cable can be set to a strength according to the vibration and steering of the drive wheel, as in the conventional case, and the connection part can be prevented from becoming large.

1 is a perspective view illustrating a mounting structure between an in-wheel motor and a vehicle body according to an embodiment of the present invention. FIG. FIG. 2 is a schematic diagram showing a state in which a vehicle body and an in-wheel motor are connected by a connecting member. 11 is a schematic diagram showing a state in which the vehicle body and the motor-side connector are connected by a connecting member. FIG. 13 is a schematic diagram showing an example of a vehicle that has been derailed while the vehicle body and the motor-side connector are connected by a connecting member; FIG. 11 is a schematic diagram showing a state in which an in-wheel motor and a power supply connector are connected by a connecting member. FIG. FIG. 13 is a schematic diagram showing an example of a wheel removal while an in-wheel motor and a power supply connector are connected by a connecting member.

Fig. 1 shows a perspective view of an example of an in-wheel motor vehicle according to an embodiment of the present invention. The in-wheel motor vehicle (hereinafter simply referred to as vehicle) 1 shown in Fig. 1 is a front-drive type in which a motor (hereinafter referred to as in-wheel motor) 2 is housed in each of a pair of front wheels, and Fig. 1 shows a perspective view of the area near the right front wheel as seen from the rear side of the vehicle 1. For convenience, the right front wheel and the right front wheel side wheel are not shown in Fig. 1.

The in-wheel motor 2 shown in Figure 1 is held so that it can move up and down relative to the vehicle body 3. Specifically, a knuckle 5 that functions as part of the case of the in-wheel motor 2 is connected to the tip of a suspension 4 that is configured in the same way as a conventional suspension.

The end of a tie rod (or knuckle arm) 6 that moves in the vehicle width direction according to the steering amount of the steering wheel is connected to the knuckle 5 so that the knuckle 5 swings around the central axis of the suspension 4 according to the steering angle of the steering wheel (not shown). That is, the in-wheel motor 2 is held to the vehicle body by the suspension 4 and the tie rod 6. Note that the in-wheel motor 2 in the embodiment of the present invention is not limited to being supported by the vehicle body 3 by the suspension 4 and the tie rod 6, but may be supported by a lower arm, an upper arm, or the like. The in-wheel motor 2 is not limited to being provided on the front wheel, but may be provided on the rear wheel, in which case the tie rod 6 does not need to be connected.

The in-wheel motor 2 shown in FIG. 1 is configured in the same manner as a conventionally known motor provided as a driving force source for an electric vehicle or hybrid vehicle. That is, it can output a driving torque according to the power supplied, and also functions as a generator that converts the kinetic energy of the driving wheels into electrical energy by outputting a braking torque to reduce the rotation speed of the driving wheels. Specifically, it is configured as a conventionally known AC motor such as a permanent magnet synchronous motor or induction motor.

The in-wheel motor 2 shown in FIG. 1 is an outer rotor type motor in which a rotor is provided on the outer periphery of a stator, and is equipped with a rotor cover 2a that rotates integrally with the rotor. A brake disc 7 formed in an annular shape is integrated into the rotor cover 2a on the vehicle body 3 side. A brake caliper 8 is provided on the outer periphery of the brake disc 7, and is configured to apply a braking torque to the drive wheel according to the frictional force between the brake caliper 8 and the brake disc 7 by clamping the brake disc 7 with the brake caliper 8. Furthermore, a hub 9 is formed on the outer side of the rotor cover 2a in the vehicle width direction for fixing a wheel (not shown) with bolts and nuts.

A power source (not shown) that supplies power to the in-wheel motor 2 configured as described above and charges the power generated by the in-wheel motor 2 is mounted on the vehicle body 3. This power source is similar to power sources provided in conventionally known electric vehicles and hybrid vehicles, and in order to output a direct current, an inverter is provided to convert the current into an alternating current. In the example shown in FIG. 1, the inverter is provided on the vehicle body 3. Therefore, three cables (three-phase cables) 10 are provided to pass the three-phase current generated by the inverter to the in-wheel motor 2. The inverter may be provided inside the in-wheel motor 2, in which case a cable (PN cable) for electrically connecting the power source and the inverter may be provided instead of the three-phase cable 10.

The cable 10 described above is arranged so as to be routed rearward of the suspension in the longitudinal direction of the vehicle 1, as shown in Figs. 1 and 2. Furthermore, in order to prevent a tensile load from acting on the cable 10 even when the drive wheels are turned, the overall length of the cable 10 is made longer than the shortest distance between both ends of the cable 10 when the drive wheels are turned to the maximum extent. Furthermore, the strength of the connection between the vehicle body 3 and the cable 10 and the connection between the in-wheel motor 2 and the cable 10 is determined based on the load acting on these connections due to the vibration and turning of the drive wheels.

When the vehicle 1 configured as described above collides with an obstacle at the front to the right of the center in the vehicle width direction, there is a possibility that the suspension 4 or the connection between the tie rod 6 and the knuckle 5 will break, causing the vehicle to derail. Furthermore, collision experiments have shown that in the event of such a collision, the part supporting the upper end of the suspension 4 will not break and will remain held by the vehicle body 3.

Therefore, the in-wheel motor vehicle 1 in this embodiment of the invention is configured to prevent the cable 10 from breaking when the drive wheel on which the in-wheel motor 2 is provided derails as described above. Specifically, a connecting member 11 is provided to prevent the drive wheel from separating from the vehicle body 3 when the suspension 4 or the connection between the tie rod 6 and the knuckle 5 breaks and the wheel derails.

Figure 2 is a schematic diagram for explaining the configuration. The connecting member 11 shown in Figure 2 is arranged rearward of the suspension 4 on the vehicle 1, with one end fixed to the vehicle body 3 by a bolt or the like, and the other end fixed to the knuckle 5 by a bolt or the like. The connecting member 11 is also configured to be bendable.

Furthermore, the connecting member 11 is formed longer than the shortest distance between the attachment part of the connecting member 11 to the vehicle body 3 and the attachment part of the connecting member 11 to the knuckle 5 when the suspension 4 is displaced to its maximum and the drive wheels are steered to its maximum, and is also formed shorter than the entire length of the cable 10.

Furthermore, the connecting member 11 is configured to have a strength that is greater than or equal to the strength that can absorb the weight of the drive wheel including the in-wheel motor 2 and the kinetic energy of the drive wheel calculated from the speed at the time of collision. In other words, the connecting member 11 is configured to have a strength that will not break even if the connecting member 11 is stretched when the drive wheel derails.

As described above, by connecting the in-wheel motor 2 and the vehicle body 3 with the connecting member 11, even if the drive wheel derails, it is possible to prevent the derailed drive wheel and the vehicle body 3 from separating by more than the full length of the connecting member 11. In other words, by setting the full length of the connecting member 11 to a length less than the full length of the cable 10, it is possible to prevent a tensile load from acting on the cable 10 when the wheel derails, and to prevent the cable 10 from breaking. In other words, the cable 10 can be set to a strength according to the vibration and steering of the drive wheel, as in the conventional case, and the connection part can be prevented from becoming large.

As described above, the suspension 4 is held by the vehicle body 3 even if the vehicle 1 collides with an obstacle in front and derails. Therefore, by arranging the connecting member 11 rearward of the vehicle 1 relative to the suspension 4, it is possible to prevent the connecting member 11 from being subjected to a load that exceeds the expected range, which would otherwise be caused by the suspension 4 coming into contact with the connecting member 11 when the vehicle derails. In other words, it is possible to prevent the connecting member 11 from breaking and causing an excessive tensile load to be applied to the cable 10.

Furthermore, by arranging the cable 10 behind the suspension 4 of the vehicle 1, it is possible to prevent a situation in which a tensile load acts on the cable 10 before the connecting member 11 bears the weight of the drive wheel that has derailed due to a part of the cable 10 unintentionally getting caught on the suspension 4 when the wheel derails.

The connecting member 11 in this embodiment of the invention is not limited to connecting the in-wheel motor 2 and the vehicle body 3, as long as it can suppress the application of tensile load to the cable 10. Figures 3 and 4 show an example of another configuration. In the example shown in Figures 3 and 4, a socket 3a is formed on the in-wheel motor 2, and a motor-side connector 10a connected to the socket 3a is formed on one end of the cable 10. This motor-side connector 10a is formed based on, for example, protection class IPXXB.

The motor side connector 10a and the vehicle body 3 are connected by the connecting member 11. The strength of the connecting member 11 is greater than the strength of the mating portion between the socket 3a and the motor side connector 10a. In other words, when the connecting member 11 is pulled in the direction of pulling the motor side connector 10a out of the socket 3a, the connecting portion between the motor side connector 10a and the socket 3a breaks without breaking the connecting member 11. As in the above example, the connecting member 11 is formed to be shorter than the length of the cable 10, and the connecting member 11 and the cable 10 are arranged rearward of the suspension 4 on the vehicle 1.

As described above, by connecting the motor side connector 10a and the vehicle body 3 via the connecting member 11, in the event of a wheel derailment as shown in FIG. 4, the motor side connector 10a is pulled out of the socket 3a by the connecting member 11. In other words, the distance between the vehicle body 3 and the motor side connector 10a can be prevented from becoming greater than the full length of the connecting member 11. As a result, it is possible to prevent a tensile load from acting on the cable 10, which is formed with a total length longer than the connecting member 11, and to prevent the cable 10 from breaking.

In the above example, the connecting member 11 is provided to break the connection between the in-wheel motor 2 and the cable 10, but the connecting member 11 may also be provided to break the connection between the vehicle body 3 and the cable 10. An example of such a configuration is shown in Figures 5 and 6. In the example shown here, a socket 3a is formed on the vehicle body 3, and a power supply connector 10b that is connected to the socket 3a is formed on the end of the cable 10. This power supply connector 10b is formed, for example, based on protection class IPXXB.

The power supply connector 10b and the in-wheel motor 2 are connected by a connecting member 11. The strength of the connecting member 11 is greater than the strength of the fitting portion between the socket 3a and the power supply connector 10b. In other words, when the connecting member 11 is pulled in the direction in which the power supply connector 10b is pulled out of the socket 3a, the connecting portion between the power supply connector 10b and the socket 3a breaks without breaking the connecting member 11. As in the above example, the connecting member 11 is shorter than the length of the cable 10, and the connecting member 11 and the cable 10 are arranged rearward of the suspension 4 on the vehicle 1.

As described above, by connecting the power supply connector 10b and the in-wheel motor 2 via the connecting member 11, in the event of a wheel derailment as shown in FIG. 6, the power supply connector 10b is pulled out of the socket 3a by the connecting member 11. In other words, the distance between the in-wheel motor 2 and the power supply connector 10b can be prevented from exceeding the full length of the connecting member 11. As a result, it is possible to prevent a tensile load from acting on the cable 10, which is formed with a full length longer than the connecting member 11, and to prevent the cable 10 from breaking.

Note that the in-wheel motor in this embodiment of the invention is not limited to being installed on the front wheels, but may also be installed on the rear wheels, in which case the connecting members and cables should be arranged forward of the suspension on the vehicle.

REFERENCE SIGNS LIST 1 In-wheel motor vehicle 2 In-wheel motor 2b, 3a Socket 3 Vehicle body 4 Suspension 5 Knuckle 6 Tie rod 10 Cable 10a Motor side connector 10b Power supply side connector 11 Connecting member

Claims (1)

An in-wheel motor vehicle including a drive wheel, an in-wheel motor provided inside the drive wheel and outputting torque to the drive wheel, a power source provided on a vehicle body, and a cable electrically connecting the power source and the in-wheel motor,
a suspension having an upper end held by the vehicle body and supporting the in-wheel motor so as to be movable up and down;
a connecting member connected to the vehicle body and the in -wheel motor, or connected to a power supply side connector that attaches the cable to the power supply and the in-wheel motor, or connected to a motor side connector that attaches the cable to the in-wheel motor and the vehicle body ,
The connecting member is provided on the inner side of the suspension in the front-rear direction of the vehicle body and is formed to be bendable,
An in-wheel motor vehicle, characterized in that the length of the connecting member is longer than the shortest distance between the mounting portion of the connecting member on the vehicle body side and the mounting portion of the connecting member on the in-wheel motor side when the suspension is displaced to its maximum and the drive wheels are steered to its maximum, and is shorter than the cable.

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