JP2005289321A - In-wheel motor installation all-wheel-drive vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an all-wheel-drive vehicle that is of type where one of the front wheel and the rear wheel is driven by an internal combustion engine and the other is driven by an electric motor mounted in a wheel section, has high space efficiency, and has high running property and comfortable ride quality. <P>SOLUTION: In the all-wheel-drive vehicle, a motor is supported in a wheel section on the driven side by the motor with a buffer mechanism 10. In the buffer mechanism 10, the operation direction of a knuckle mounting plate 14 and a motor mounting plate 15 is limited to the vertical direction of the vehicle via a direct acting guide 11 with respect to underbody components of the vehicle, they are interconnected through a spring element 12 acting in the vertical direction of the vehicle and a damper 13 arranged in parallel with the spring element 12. The wheel section has the in-wheel motor 3 where a rotor 3R of the motor 3 and the wheel 2 are interconnected through a driving force transmission mechanism 20 where a motor-side plate 21 and a wheel-side plate 22 are interconnected inside out through a plurality of cross guides 23 arranged so that the acting directions intersect perpendicularly. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an all-wheel drive vehicle, and more particularly, to an all-wheel drive vehicle in which either a front wheel or a rear wheel is driven by an internal combustion engine and the other is driven by an electric motor mounted on a wheel portion.

Conventionally, when an all-wheel drive vehicle is made based on a front wheel drive vehicle, for example, as shown in FIG. 18 (a), a drive shaft 41a, a transfer differential (diff) 41b, A power transmission mechanism 41 such as a propeller shaft 41c and a transfer 41d is added to transmit the driving force from the internal combustion engine 42 to the rear wheels 40R and 40R. Such a method is generally widely used. However, even in the same type of vehicle, in order to secure a space for adding the above parts to the vehicle, a vehicle body 40 for all-wheel drive is separately provided. In addition to the necessity to prepare, there is a problem that the living space is reduced due to an increase in the number of mounted parts.
Therefore, in recent years, as shown in FIG. 18B, a generator 43 is attached to the internal combustion engine 42, and the front wheels 40F and 40F are driven by the internal combustion engine 42. An all-wheel drive vehicle is proposed in which the rear wheels 40R and 40R are driven using an electric motor 44 mounted on the rear portion of the vehicle body 40 independently of the vehicle 42. In the figure, reference numeral 44C denotes a motor controller for controlling the electric motor 44. This method is advantageous in that a transfer space 41d and a propeller shaft 41c for transmitting power from the front portion of the vehicle body 40 to the rear portion of the vehicle body 40 are not required, so that the living space can be expanded and the vehicle weight can be reduced.

On the other hand, as shown in FIG. 18C, if the motor 44 mounted on the rear part of the vehicle body 40 is mounted under the spring to be an in-wheel motor, the differential 41b and the drive shaft 41a are not required. For this reason, it is possible to dramatically increase the living space of the vehicle.
As shown in FIG. 18 (d), when the front wheels are hybridized, if the motor 44 is mounted under the springs of the front wheels 40F and 40F to form an in-wheel motor, the living space of the vehicle is dramatically increased. Can be increased.
Usually, as the motor, for example, a motor 44M with a reduction gear as shown in FIG. 19 is often used. This motor 44M is an inner rotor type motor in which a stator 44S fixed to a motor case 44a on the outer peripheral side and a rotor 44R with a motor shaft 44c fixed to the inner peripheral side via a support member 44b are arranged. The motor shaft 44c is rotatably supported by a bearing 44d installed on the motor case 44a and a bearing 44g installed on a carrier 44f of a planetary gear type speed reducer 44e. The motor shaft 44c is an output shaft of the speed reducer 44e. A shaft portion 44h of the carrier 44f is connected to an output shaft of a clutch (not shown) so as to be able to transmit rotation (see, for example, Patent Document 1).

Further, as a direct drive type in-wheel motor having no speed reducer, an outer rotor type in-wheel motor 53 as shown in FIG. 20 has been proposed. In the in-wheel motor 53, the stator 53S is connected to and supported by the upright 57 that is a fixed portion, and is disposed inside the wheel disk 52b of the direct drive wheel 52, and the rotating shaft connected to the wheel disk 52b. 54 is coupled to the bearing 54J. The rotor 53R disposed on the outer peripheral side of the stator 53S has a first bracket 55a coupled to the rotating shaft 54, and a second fixed rotatably through the upright 57 and the bearing 57J. It is supported by the bracket 55b. Thereby, since the rotor 53R is rotatably coupled to the stator 53S, the rotational force can be transmitted to the wheel 52 by driving the in-wheel motor 53, and the wheel 52 can be directly driven. (For example, refer to Patent Document 2).
JP 2003-32806 A Japanese Patent No. 2676025

By the way, in a vehicle equipped with a suspension mechanism such as a spring around the undercarriage, the larger the mass of the unsprung parts such as wheels, knuckles, and suspension arms, the larger the so-called unsprung mass, It is known that the ground load fluctuation increases and the load holding property deteriorates. As described above, a conventional in-wheel motor is mounted directly under the vehicle spring, or a spindle shaft that is connected to a part called an upright or a knuckle where the motor part is one of the parts constituting the undercarriage of the vehicle. Therefore, the unsprung mass is increased by the mass of the motor. Therefore, compared with the all-wheel drive vehicle having the configuration shown in FIGS. 18A and 18B (hereinafter referred to as a conventional all-wheel drive vehicle), the riding comfort and the tire ground contact performance on the rear wheel side are deteriorated. Have the problem.
In particular, deterioration of ground contact is an important issue. If the ground contact, that is, the road surface following property of the tire deteriorates, a phenomenon that the tire jumps up from the road surface occurs even on a rough road surface, and the tire ground load decreases. To do. When the ground contact load of the tire is reduced, the maximum allowable driving force applied to the tire is also reduced. Therefore, in a vehicle equipped with a conventional in-wheel motor, the driving force applied is smaller than that of a wheel having a normal undercarriage. On the other hand, in the conventional all-wheel drive vehicle described above, the front and rear wheels have normal underspring and a light undercarriage, and the tires have high ground contact properties. Can distribute power.

In other words, in a conventional vehicle equipped with an in-wheel motor, the front wheel is a light undercarriage under a normal spring and the rear wheel is a heavy undercarriage under a spring. Due to the significant decrease, a large driving force could not be distributed to the rear wheels. In other words, the above-mentioned conventional in-wheel motor-equipped vehicle has a lower total driving force than the conventional all-wheel drive vehicle. There was a problem that it could not be demonstrated.
In this way, the conventional all-wheel drive vehicle has good running performance and ride comfort, but there is a problem that the space efficiency deteriorates, and the conventional in-wheel motor equipped vehicle has good space efficiency, but the running performance and There is a problem that the ride comfort deteriorates, and an all-wheel drive vehicle with improved performance in all items has not been realized.

  An object of the present invention is to provide an all-wheel-drive vehicle that is excellent in space efficiency and excellent in running performance and ride comfort.

According to a first aspect of the present invention, an auxiliary drive electric motor is provided under a non-drive wheel spring below the non-drive wheel of a vehicle that drives either the front wheel or the rear wheel by the rotational force of the internal combustion engine. On the other hand, an in-wheel motor having a structure supported in the vertical direction by a viscous element and an elastic element is mounted.
According to a second aspect of the present invention, in the all-wheel drive vehicle equipped with the in-wheel motor according to the first aspect, the motor is supported by a viscous element and an elastic element in the front-rear direction in addition to the vertical direction. is there.
According to a third aspect of the present invention, in the all-wheel drive vehicle equipped with the in-wheel motor according to the first or second aspect, the motor is also mounted on a wheel driven by an internal combustion engine.
According to a fourth aspect of the present invention, in the all-wheel drive vehicle equipped with the in-wheel motor according to any one of the first to third aspects, the motor is an in-wheel motor having a geared motor structure.

According to the present invention, the auxiliary driving electric motor is applied to the non-driving wheel of the vehicle that drives either the front wheel or the rear wheel by the rotational force of the internal combustion engine with respect to the lower part of the non-driving wheel. In addition, an in-wheel motor having a structure supported in the vertical direction by the elastic element is mounted and the motor is operated as a dynamic damper device, so that unsprung vibration can be suppressed and the minimum grounding of the tire is achieved. The power can be increased. Therefore, it is possible to obtain an all-wheel drive vehicle that is excellent in space efficiency and excellent in running performance and riding comfort.
Furthermore, if the motor is supported in the longitudinal direction by the viscous element and the elastic element in addition to the vertical direction, fluctuations in the longitudinal force of the tire can be greatly suppressed, and the stability of the driving force can be reduced. Riding comfort can be further enhanced.

Hereinafter, the best mode of the present invention will be described with reference to the drawings.
Best Mode
FIG. 1 is a diagram showing a configuration of a wheel portion on the side driven by an in-wheel motor in an all-wheel drive vehicle equipped with an in-wheel motor according to the best mode 1. In the figure, 1 is a tire, 2 is a wheel made up of a rim 2a and a wheel disc 2b, and 3 is a motor stator (hereinafter referred to as a stator) fixed to a non-rotating side case 3a provided inside in the radial direction. 3S and a motor rotor (hereinafter referred to as a rotor) 3R fixed to a rotating side case 3b that is provided on the outer side in the radial direction and is rotatably joined to the non-rotating side case 3a via a bearing 3j. Is an outer rotor type in-wheel motor.
4 is a hub portion connected to the wheel 2 and its rotating shaft, 5 is a knuckle coupled to the axle 6, 7 is a suspension member such as a shock absorber, and 8 is a braking device attached to the hub portion 4. Are coupled to each other by a spring element 12 whose operation direction is limited in the vertical direction of the vehicle, and which is operated in the vertical direction of the vehicle, and a damper 13 arranged in parallel with the spring element 12 via the linear motion guide 11. A shock absorbing mechanism for connecting the non-rotating side case 3a of the motor and the knuckle 5 which is an undercarriage part of the vehicle, and 20 is a hollow disk attached to the rotating side case 3b of the motor. The motor-side plate 21 and the wheel-side plate 22 attached to the wheel 2 are connected to each other by a plurality of cross guides 23 arranged so that the operating directions are orthogonal to each other. Combined, a driving force transmission mechanism for transmitting the rotational force of the motor 3 to the wheel 2.

As shown in FIG. 2, the buffer mechanism 10 is connected to an axle 6 coupled to a knuckle 5, and springs that expand and contract in the vertical direction of the vehicle at four corners of a knuckle mounting plate 14 located on the suspension member 7 side. Each of the elements 12 is mounted, and dampers 13 that extend in the vertical direction of the vehicle are mounted on both sides of the connecting hole 14h with the axle 6 provided at the center thereof, and a motor mounting plate that is mounted on the non-rotating side case 3a of the motor. A spring receiving portion 12n is attached to a position corresponding to the upper or lower portion of the spring element 12, and a damper mounting portion 13n is attached to a position corresponding to the upper portion of the damper 13. The plates 14 and 15 are placed at the center of the plate. These are coupled by four linear motion guides 11 arranged at symmetrical positions.
By adopting the above-described configuration, the in-wheel motor 3 is supported in the vertical direction by the viscous element and the elastic element with respect to the knuckle 5 that is a vehicle undercarriage part. It can be floating mounted against the lower part of the spring.
Accordingly, the mass of the motor 3 is separated from the unsprung mass equivalent of the vehicle and acts as a so-called dynamic damper weight, so that only the dynamic damper effect is added without increasing the unsprung mass. The damping force generated by the dynamic damper acts so as to calm the unsprung vibration during running on uneven roads, so that the minimum grounding load of the tire is raised with respect to vibration input. As a result, a large driving force can be transmitted to the tire, so that the running performance is improved. In addition, since a part of the vibration input from the road surface can be absorbed by the dynamic damper portion, riding comfort is also improved.

Next, the driving force transmission mechanism 20 will be described.
As shown in FIG. 3A, the cross guide 23 used in the driving force transmission mechanism 20 includes a first guide rail 23A, which is a beam-like member mounted on the motor side plate 21, and a wheel side plate 22. The first guide rail 23A and the second guide rail 23B are provided with a second guide rail 23B arranged on the upper surface and a cross guide body 23C provided with guide grooves 23a and 23b on the upper and lower surfaces, respectively. Can operate in directions orthogonal to each other along the guide grooves 23a and 23b of the cross guide body 23C.
In this example, as shown in FIG. 3B, four cross guides 23 are arranged at equal intervals (90 ° intervals) between the motor side plate 21 and the wheel side plate 22, and each cross The first guide rails 23 </ b> A of the guides 23 are arranged so that their operating directions are all 45 ° with respect to the radial direction of the plate 21. Therefore, the operating directions of the first guide rails 23A are all in the same direction (45 ° direction), and the operating directions of the second guide rails 23B are relative to the operating directions of the first guide rails 23A. The directions are orthogonal to each other. Thereby, the rotational force from the rotation side case 3b of the in-wheel motor 3 is first input to the first guide rail 23A via the motor side plate 21, and the circumference input to the first guide rail 23A. The direction force is transmitted to the second guide rail 23B through the cross guide body 23C, and is transmitted to the wheel 2 through the wheel side plate 22.
At this time, a force rotating in the circumferential direction and a force pushing outward in the radial direction act on the cross guide main body 23C due to an input from the first guide rail 23A and a reaction from the second guide rail 23B. However, the first guide rail 23A and the second guide rail 23B move in the rotating direction, but always try to keep the directions orthogonal to each other, so that the force for pushing the cross guide 23 outward in the radial direction is used. Is balanced with the torsional reaction force of the cross guide body 23C. As a result, the eccentricity can be absorbed only by the plurality of cross guides 23.
In the best mode 1, since the motor 3 is elastically supported by the buffer mechanism 10, the motor rotor shaft and the wheel shaft are relatively eccentric. However, the rotor 3R and the wheel 2 are connected to the driving force transmission mechanism 20 in the first embodiment. Even when the above eccentricity occurs, the torque from the rotor 3R can be smoothly transmitted to the wheel 2.

As described above, in the best mode 1, in an all-wheel drive vehicle, a knuckle mounting plate in which the motor 3 is connected to the knuckle 5 with respect to the undercarriage part of the vehicle on the wheel portion driven by the motor. 14 and the motor attachment plate 15 attached to the non-rotating side case 3a of the motor, the spring element 12 having an operation direction limited to the vertical direction of the vehicle and operating in the vertical direction of the vehicle via the linear guide 11 and the above A motor side plate in which the rotor 3R of the motor 3 and the wheel 2 are supported by a buffer mechanism 10 configured to be coupled by a damper 13 disposed in parallel with the spring element 12, and the rotor 3R and the wheel 2 of the motor 3 are attached to the rotation side case 3b of the motor. 21 and the wheel side plate 22 attached to the wheel 2 are arranged on a plurality of cross guides 23 arranged so that the operation directions are orthogonal on the front and back sides. Since the in-wheel motor 3 configured to be coupled by the driving force transmission mechanism 20 coupled to each other is mounted and the motor 3 is configured to operate as a weight device for a dynamic damper, unsprung vibration during running on uneven roads is reduced. The minimum ground load of the tire can be raised with respect to vibration input. Moreover, the rotational force of the motor 3 can be reliably transmitted to the wheel 2 by using the driving force transmission mechanism 20 having the cross guide.
Therefore, a large driving force can be transmitted to the tire, the running performance can be improved, and a part of the vibration input from the road surface can be absorbed by the dynamic damper portion, so that the riding comfort can also be improved. it can.
In addition, since the in-wheel motor having the above-described configuration is mounted on the wheel portion of the all-wheel-drive vehicle that is driven by the motor, there is no need for a differential or a drive shaft, and the living space of the vehicle is dramatically increased. be able to.

Best Mode 2
In the best mode 1, the case where the vertical vibration of the vehicle is reduced has been described. However, the in-wheel motor 3 is supported by the viscous element and the elastic element in the longitudinal direction in addition to the vertical direction. By doing so, fluctuations in the longitudinal force of the tire can be greatly suppressed, and the stability of the driving force and the ride comfort can be further enhanced.
That is, as shown in FIG. 4 and FIG. 5, the non-rotating side case 3a is attached to the outer periphery of a disc-like motor attachment member 16A having a notch 16h formed in the center. A motor vertical support member 16B having a long axis is coupled to a damper 17 composed of a spring member mounted on a slide guide 17G for guiding the vehicle in the vertical direction and a linear guide 18A for guiding the vehicle in the vertical direction. Buffer mechanism 10Z having a configuration in which the motor vertical support member 16B and the hollow disk-shaped knuckle attachment member 16C attached to the knuckle 5 which is a fixed portion are coupled by an elastic body 18 and a linear guide 18B which guides the vehicle in the longitudinal direction. When the in-wheel motor 3 is supported in the vehicle vertical direction via a linear motion guide and an elastic body, Moni, the vertical direction support part relative to the knuckle 5 which is a part around, via a linear guide and the elastic body, can be supported in the vehicle longitudinal direction.
As a result, the in-wheel motor 3 can be floating mounted on the unsprung part that is the undercarriage part of the vehicle, and the motor shaft and the wheel shaft can swing separately in the longitudinal direction of the vehicle. The fluctuation in tire longitudinal force can also be reduced, and the tire generating force in the longitudinal direction can be stabilized. Therefore, the running performance can be further improved, and the vibration in the longitudinal direction of the vehicle can be reduced, so that the riding comfort is further improved.

In the best modes 1 and 2, the lower part of the wheel not driven by the internal combustion engine is supported in the vertical direction, or in the vertical direction and the front and rear direction by the viscous element and the elastic element with respect to the lower part of the spring. The case where the in-wheel motor 3 is mounted has been described, but the motor 3 can also be mounted on a wheel driven by the internal combustion engine. Specifically, as shown in FIG. 6, a connecting portion to an output shaft (drive shaft) 9 of an internal combustion engine (not shown) is connected to a hub portion 4 connected to a wheel 2 and its rotating shaft, similarly to a normal automobile. And the hub portion 4 and the drive shaft 9 are connected to each other.
As a result, the total driving force of the vehicle can be further increased, and the wheel driven by the internal combustion engine also has higher performance with respect to tire ground load fluctuations than when a conventional in-wheel motor is mounted. The stability of the driving force and the ride comfort can be further enhanced.
Further, if the generator directly attached to the internal combustion engine is omitted and the in-wheel motor 3 attached to the wheel on the internal combustion engine side is used as a generator, all the wheels can be produced without any significant modification around the internal combustion engine. A drive vehicle can be realized.

Further, in the above example, the case where a hollow direct drive motor is used as the in-wheel motor 3 has been described. However, when there is room in the space, instead of the motor 3, as shown in FIG. If the geared motor 30 in which the electric motor 31 and the reduction gear (planetary reduction gear) 32 are integrally incorporated in the motor case 33 is mounted, the driving force of the vehicle can be further improved.
As a method of supporting the geared motor 30 with respect to the unsprung part of the non-driven wheel by a viscous element and an elastic element, as shown in FIG. 7, a motor case 33 which is a non-rotating part is guided in the vehicle vertical direction. It is attached to a hollow disk-shaped motor attachment member 36 via a linear motion guide 34A and an elastic body 35A, and this motor attachment member 36 is fixed via an elastic body 34B and a linear motion guide 35B that guides the vehicle in the longitudinal direction. What is necessary is just to make it attach to the hollow disk-shaped knuckle attachment member 37 attached to the knuckle 5 which is a part. At this time, the output of the geared motor 30 is transmitted to the wheel 2 by connecting the output shaft of the reduction gear 32 and the wheel 2 by a shaft 38 having a universal joint 38j.
As a result, the geared motor 30 is supported in the vehicle vertical direction via the linear motion guide and the elastic body, and the vertical direction support component is supported in the vehicle longitudinal direction with respect to the knuckle 5 which is the undercarriage component. Therefore, the geared motor 30 can be mounted in a floating manner on the unsprung portion that is a vehicle suspension part. Therefore, even when the geared motor 30 is mounted, the fluctuation of the tire contact force can be reduced, the load holding performance of the vehicle can be improved, and the fluctuation of the tire longitudinal force can also be reduced, so that the tire performance is stabilized. can do.

The table in FIG. 8 is a table showing parameters representing characteristics in the vertical direction of the vehicle for analyzing the ground load fluctuation generated in the tire when the vehicle travels on a rough road. 10 and FIG. 10 are graphs showing the frequency characteristics of the tire minimum ground contact force and the sprung vibration acceleration analyzed by the vibration model. The minimum tire contact force represents the contact force when the vehicle is traveling on a rough road when the tire contact load is the smallest. The larger the tire minimum contact force, the stronger the tire is pressed against the road surface. Therefore, a state where a greater driving force can be applied, that is, the running performance is high.
In the table of FIG. 8 above,
・ M1 is the unsprung mass of the wheel, etc. ・ m2 is the mass of the spring of the body, etc. ・ m3 is the mass of the motor that is a dynamic damper. ・ K1 is the tire longitudinal spring constant ・ k2 is the spring constant in the vertical direction of the suspension ・ k3 is the motor supporting spring constant C1 is a tire vertical damping coefficient, c2 is a suspension vertical damping constant, and c3 is a motor support damper vertical damping coefficient.
Comparative example 1 in the table is a condition on the driven wheel side of the two-wheel drive vehicle, and comparative example 2 is a motor-mounted type all-wheel drive vehicle that can be represented by the vibration model of FIG.
Comparative Example 3 is a conventional all-wheel drive vehicle equipped with an in-wheel motor mounted under a motor spring, which can be represented by the vibration model shown in FIG. 9B.
Moreover, Examples 1-3 of a table | surface are all-wheel drive vehicles carrying the dynamic damper type in-wheel motor of this invention which can be represented with the vibration model of FIG.
When the all-wheel drive motor is mounted on the vehicle body as in Comparative Example 2, the vehicle body mass and the sprung mass are less than the driven wheel side conditions of the two-wheel drive vehicle that does not have a drive device as in Comparative Example 1. 11 and 12, the minimum grounding force is improved and the sprung vibration is also reduced, so that ride comfort is also improved.
However, as in Comparative Example 3, when the motor is directly attached to the unsprung mass equivalent part of the wheel, knuckle or the like, as shown in FIGS. Not only does the minimum ground contact force decrease, but the sprung vibration also increases, so the ride performance is extremely deteriorated.
On the other hand, if the motor is mounted as a dynamic damper as in the first embodiment of the present invention, the motor mass disappears from the unsprung mass, so that the unsprung mass is reduced to the same level as in the first and second comparative examples. Moreover, the unsprung vibration is suppressed by the action of the dynamic damper. For this reason, as shown in FIG. 11, the minimum ground contact force of the tire increases in a wide range, and the running performance is improved as compared with the case where the motor as in Comparative Example 2 is mounted on the vehicle body. Further, as shown in FIG. 12, the sprung vibration is further reduced, so that riding comfort is also improved.
Moreover, the all-wheel drive vehicle of this invention has the characteristics that a high performance can be maintained even if the value of the spring which supports a motor, or the shock absorber changes greatly like Example 2, 3. FIG.

The table in FIG. 13 is a table showing parameters representing characteristics in the longitudinal direction of the vehicle for analyzing the longitudinal force fluctuation generated in the tire when the vehicle travels on a rough road, and FIGS. 14 (a) and 14 (b). 15 and 15 are graphs showing the vibration model, and FIGS. 16 and 17 are graphs showing the frequency characteristics of the longitudinal force fluctuation and the sprung vibration acceleration analyzed by the vibration model, respectively. The smaller the longitudinal force fluctuation is, the smaller the tire can stably exhibit high force. Therefore, the smaller the longitudinal force, the higher the ground contact of the tire.
In the table of FIG.
· K1 'is the tire longitudinal spring constant · k2' is the spring longitudinal spring constant · k3 'is the motor supporting spring constant · c1' is the tire longitudinal damping coefficient · c2 'is the suspension longitudinal damping constant · c3' is the motor supporting Damper longitudinal damping coefficient.
Comparative Example 1 in Table 2 is a condition on the driven wheel side of the two-wheel drive vehicle, and Comparative Example 2 is a motor-mounted all-wheel drive vehicle that can be represented by the vibration model of FIG.
Comparative Example 3 is a conventional all-wheel drive vehicle equipped with an in-wheel motor of a motor unsprung type, which can be represented by the vibration model of FIG.
Examples 1 to 3 in Table 2 are all-wheel drive vehicles equipped with a dynamic damper type in-wheel motor of the present invention, which can be represented by the vibration model of FIG.
When the all-wheel drive motor is mounted on the vehicle body as in Comparative Example 2, the vehicle body mass and the sprung mass are less than the driven wheel side conditions of the two-wheel drive vehicle that does not have a drive device as in Comparative Example 1. As shown in FIG. 16 and FIG. 17, the longitudinal force fluctuation characteristics hardly change, but the sprung vibration is reduced, so that the riding comfort is improved.
However, when the motor is directly attached to the unsprung mass equivalent part such as a wheel or a knuckle as in Comparative Example 3, as shown in FIG. This increases not only the driving force of the wheels but also the vibration on the spring as shown in FIG.
On the other hand, if the motor is mounted as a dynamic damper as in the first embodiment of the present invention, the motor mass disappears from the unsprung mass, so that the unsprung mass is reduced to the same level as in the first and second comparative examples. Moreover, the unsprung vibration is suppressed by the action of the dynamic damper. For this reason, as shown in FIG. 16, the fluctuation of the longitudinal force of the tire increases in a wide range, and the running performance is improved as compared with the case where the motor as in Comparative Example 2 is mounted on the vehicle body. Further, as shown in FIG. 17, the sprung vibration is further reduced, so that ride comfort is also improved.
Moreover, the all-wheel drive vehicle of this invention has the characteristics that a high performance can be maintained even if the value of the spring which supports a motor, or the shock absorber changes greatly like Example 2, 3. FIG.

  As described above, according to the present invention, in the all-wheel drive vehicle equipped with an in-wheel motor in which either the front wheel or the rear wheel is driven by the internal combustion engine and the other is driven by the motor mounted on the wheel portion, If an in-wheel motor with a structure supported in the vertical direction by a viscous element and an elastic element is used for the lower part of the vehicle spring as the motor, the tire ground contact force can be improved and the vibration on the spring is greatly increased. Therefore, it is possible to realize an all-wheel drive vehicle that is excellent in space efficiency and excellent in running performance and ride comfort.

It is a figure which shows the structure of the wheel part by the side driven by the in-wheel motor of the all-wheel drive vehicle carrying an in-wheel motor concerning the best form 1 of this invention. It is a figure which shows the structure of the buffer mechanism concerning this best form 1. FIG. It is a figure which shows the structure of the driving force transmission mechanism concerning this best form. It is a figure which shows the structure of the in-wheel motor of the structure which supported the motor with the viscous element and the elastic element also to the front-back direction in addition to the up-down direction. It is a figure which shows the other structure of the buffer mechanism by this invention. It is a figure which shows the example which mounted the motor also on the wheel by the side driven by an internal combustion engine. It is a figure which shows the example which mounts a geared motor. It is a table | surface which shows the parameter showing the characteristic of the up-down direction of a vehicle. It is a figure which shows the vehicle vibration model (grounding load fluctuation | variation) of the case where the conventional motor is mounted in the vehicle body side, and the all-wheel drive vehicle which fixed the motor to the vehicle spring lower part. It is a figure which shows the vehicle vibration model (grounding load fluctuation | variation) of the all-wheel drive vehicle carrying an in-wheel motor of this invention. It is a figure which shows the analysis result (minimum contact force) of a vehicle vibration model. It is a figure which shows the analysis result (sprung vibration acceleration) of a vehicle vibration model. It is a table | surface which shows the parameter showing the characteristic of the front-back direction of a vehicle. It is a figure which shows the vehicle vibration model (front-back force fluctuation | variation) of the case where the conventional motor is mounted in the vehicle body side, and the all-wheel drive vehicle which fixed the motor to the vehicle spring lower part. It is a figure which shows the vehicle vibration model (front-back force fluctuation | variation) of the all-wheel drive vehicle carrying an in-wheel motor of this invention. It is a figure which shows the analysis result (front-back force fluctuation | variation) of a vehicle vibration model. It is a figure which shows the analysis result (sprung vibration acceleration) of a vehicle vibration model. It is a schematic diagram which shows the structure of the conventional all-wheel drive vehicle. It is a figure which shows the structure of the inner rotor type | mold in-wheel motor with a reduction gear mounted in the conventional all-wheel drive vehicle. It is a figure which shows the structure of the conventional direct drive type in-wheel motor.

Explanation of symbols

1 tire, 2 wheel, 2a rim, 2b wheel disc,
3 In-wheel motor, 3R motor rotor, 3S motor stator,
3a non-rotating side case, 3b rotating side case, 3j bearing, 4 hub part,
5 knuckle, 6 axle, 7 suspension member, 8 braking device,
10 shock absorbing mechanism, 11 linear motion guide, 12 spring element, 13 damper,
14 knuckle mounting plate, 15 motor mounting plate,
20 driving force transmission mechanism, 21 motor side plate, 22 wheel side plate,
23 Cross guide.

Claims (4)

  An auxiliary drive electric motor is mounted on the non-drive wheel of the vehicle that drives either the front wheel or the rear wheel by the rotational force of the internal combustion engine. An all-wheel drive vehicle equipped with an in-wheel motor, which is equipped with an in-wheel motor with a structure supported in the direction.   The in-wheel motor-equipped all-wheel drive vehicle according to claim 1, wherein the motor is supported by a viscous element and an elastic element in the longitudinal direction in addition to the vertical direction.   The in-wheel motor-equipped all-wheel drive vehicle according to claim 1 or 2, wherein the motor is also mounted on a wheel driven by an internal combustion engine.   The in-wheel motor-equipped all-wheel drive vehicle according to any one of claims 1 to 3, wherein the motor is an in-wheel motor having a geared motor structure.

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