WO2011030689A1

WO2011030689A1 - Electric automobile

Info

Publication number: WO2011030689A1
Application number: PCT/JP2010/064718
Authority: WO
Inventors: 誠安井
Original assignee: Ntn株式会社
Priority date: 2009-09-11
Filing date: 2010-08-30
Publication date: 2011-03-17
Also published as: CN102481843A; DE112010003617T5

Abstract

An electric automobile configured in such a manner that the transmission of power from the electric motor to wheels can be immediately shut off when the electric motor fails or when the ABS is activated. A two-way clutch (21) is mounted in the power transmitting system for transmitting the drive power of the electric motor (10) to the front wheels (2). The two-way clutch (21) is provided with a retainer (28) and rollers (30) retained by the retainer (28), and the two-way clutch (21) couples the drive side shaft and the driven side shaft to each other by means of the engagement of the rollers (30) caused by rotational control of the retainer (28). The transmission of power from the electric motor (10) to the front wheels (2) is immediately interrupted by controlling the engagement and disengagement of the two-way clutch (21) by conducting and interrupting electricity to the electromagnetic coil (43a) of an electromagnetic clutch (40).

Description

Electric car

The present invention relates to an electric vehicle in which a vehicle is driven only by driving an electric motor mounted on the vehicle.

In an electric vehicle in which the vehicle is driven only by driving the electric motor, when the electric motor or a control means for controlling the electric motor fails during driving of the vehicle, the driving wheel is locked and suddenly braked, and the steering becomes impossible. It becomes extremely dangerous.

In order to eliminate such inconvenience, electric vehicles are provided with a fail-safe function. As an electric vehicle having a fail-safe function, one described in Patent Document 1 has been conventionally known.

In the electric vehicle described in Patent Document 1, a clutch is incorporated in a power transmission system from an electric motor to wheels, and a determination unit that determines a failure of a control unit that controls the operation of the electric motor is provided. When it is determined that the control means is out of order, the clutch is disengaged by the hydraulic actuator, and power transmission from the electric motor to the wheels is interrupted to avoid sudden braking.

Japanese Patent No. 3747836

By the way, when a clutch such as a dog clutch is disengaged by an actuator using hydraulic pressure as a drive source as in the above-described conventional electric vehicle, a mechanical failure such as seizure of an electric motor or seizure of a support bearing suddenly occurs. In this case, a slight time lag occurs from the occurrence of the failure until the clutch is disengaged, and there is a problem in that the wheels are locked during that time, the steering becomes impossible, and the vehicle suddenly stops.

Also, since the clutch is controlled by an actuator that uses hydraulic pressure as a drive source, a hydraulic pump, a hydraulic cylinder, and hydraulic piping are required, which complicates the structure and causes a large energy loss.

Here, in a general pure electric vehicle, a multi-stage transmission is not required, and a single-stage or two-stage transmission is used. Therefore, the number of parts is smaller than that of an engine vehicle or a hybrid vehicle. The connection backlash from the motor to the wheel is small.

Also, the motor has a larger torque from the start than the engine, and also has a large moment of inertia of the rotor of the motor.

For this reason, if you depress the accelerator pedal strongly when the electric vehicle starts at a low speed and then release the depression, the large torsion that occurs in the drive parts when the pedal is depressed is suddenly released, generating a back-shake vibration, and the vibration is There is an inconvenience that it is propagated to the driver and gives anxiety to the driver and deteriorates the ride comfort.

In addition, in an electric vehicle equipped with an anti-lock braking system (ABS), the braking force is applied to and released from the wheel repeatedly in a short time of several milliseconds. In the connected state, the wheel continues to rotate due to the inertia of the rotor having a large inertial force of the electric motor, the followability of the wheel to the ABS control is deteriorated, the braking distance becomes long, the vehicle spins and the running is disabled. The disadvantage of becoming stable arises.

An object of the present invention is to make it possible to immediately cut off the power transmission from the motor to the wheel when the motor fails or when the ABS is operated in an electric vehicle using only the motor as a drive source.

In order to solve the above problems, in the first invention, in the electric vehicle in which the driving source is only the electric motor, and the driving force of the electric motor is transmitted to the wheels to cause the vehicle to travel, the driving force of the electric motor is reduced. The power transmission system for transmitting to the wheel has a retainer and an engagement member held by the retainer, and the drive side shaft and the driven side shaft are coupled by engagement of the engagement member by rotation control of the retainer. A configuration was adopted in which a two-way clutch and an electromagnetic clutch for controlling the engagement and disengagement of the two-way clutch by controlling the rotation of the cage by energization and interruption of the energization were adopted.

In the electric vehicle having the above-described configuration, when the electric motor breaks down while the vehicle is running, the two-way clutch is switched to the disengaged state by the electromagnetic clutch to cut off the power transmission from the electric motor to the wheels. . At this time, since the two-way clutch is controlled by the electromagnetic clutch, the two-way clutch is instantaneously switched to the disengaged state. For this reason, the wheel is locked and cannot be steered, and the vehicle does not suddenly stop.

Here, as means for detecting an abnormality such as a failure of the motor, a sensor for detecting the rotational speed of the rotating shaft of the motor and the rotational speed of the wheel is provided, and the abnormality of the motor is determined by comparing the detection signals output from each sensor. Or an acceleration sensor that detects the acceleration of the rotating shaft of the electric motor and the acceleration of the wheel, and a method of determining an abnormality of the electric motor from comparison of detection signals output from the respective acceleration sensors can be employed.

In an electric vehicle equipped with an ABS, the two-way clutch is switched to the disengaged state by an electromagnetic clutch when the ABS is operated while the vehicle is running. As a result of the switching, the electric motor and the wheel are separated from each other. Therefore, even if the rotor of the electric motor continues to rotate due to the inertia, the rotation is not transmitted to the wheel side. For this reason, the rotor does not affect the control of the ABS, and the wheel can follow the ABS control well.

Here, the following clutches 1 to 3 can be employed as the two-way clutch.

Clutch 1; a cylindrical surface on one side of the outer circumference of the input shaft connected to the driving side shaft and the inner surface of the outer ring connected to the driven side shaft and the inner side of the outer ring, and the cylindrical surface on the other side. A plurality of cam surfaces are formed between the outer ring and the input shaft, and pockets are formed at positions facing the respective cam surfaces. A roller that engages with the cylindrical surface and the cam surface by the relative rotation of the outer ring and the input shaft is incorporated in the pocket, and between the outer ring and the input shaft between the member on the side where the cam surface is formed and the cage. Roller type that incorporates a switch spring that elastically holds the cage so that the roller is held in a neutral position.

Clutch 2; a cylindrical surface on one side of the outer periphery of the input shaft connected to the driving side shaft and the inner surface of the outer ring connected to the driven side shaft and the inner side of the outer ring, and the cylindrical surface on the other side. A plurality of cam surfaces are formed between the outer ring and the input shaft, and pockets are formed at positions facing the respective cam surfaces. A roller that engages with the cylindrical surface and the cam surface by the relative rotation of the outer ring and the input shaft is incorporated in the pocket, and between the outer ring and the input shaft between the member on the side where the cam surface is formed and the cage. A roller type that incorporates a switch spring that applies rotational torque in a direction in which the roller is pushed into one narrow portion of a wedge space formed by a cylindrical surface and a cam surface.

Clutch 3; a cylindrical surface is provided on each of the inner periphery of the outer ring connected to the driven side shaft and the outer periphery of the input shaft connected to the inner side of the outer ring and connected to the driving side shaft. A retainer and a second retainer disposed inside the first retainer are assembled, and when the retainers rotate relative to each other in a pocket provided at an opposite position of the retainers, A sprag that engages with each cylindrical surface of the input shaft is incorporated, the second retainer is fixed to the input shaft, and the sprag is disposed between the first retainer and the second retainer between the cylindrical surface of the outer ring and the input shaft. Sprag type that incorporates a switch spring that urges the first cage toward one circumferential direction in a direction to engage with the cylindrical surface of the.

In any of the above-described two-way clutches, the engagement state in which the engagement member composed of the roller or the sprag transmits the rotation of the input shaft in one direction to the outer ring to the rotation of the input shaft in the other direction is transmitted. Until the switch to, the backlash is large, and the backlash is large, so when the accelerator pedal is depressed strongly, the depression is released and the torsion of the part is released. It is possible to absorb the vibration, and to suppress the transmission of the shakeback vibration to the vehicle.

The two-way clutch may be incorporated between an electric motor and a transmission that shifts the rotation of the electric motor and transmits the rotation to the wheel. A transmission that shifts the rotation of the electric motor and transmits it to the wheel, and the transmission May be incorporated between the differential that transmits the driving force output from the left and right axles, or between the differential and the axle that transmits the rotation of the electric motor to the left and right axles. Further, it may be incorporated between a pair of left and right axles and wheels connected to each of the axles.

In the electric vehicle according to the first aspect of the present invention, an armature that is prevented from rotating by a cage and is supported so as to be movable in the axial direction as an electromagnetic clutch, and that is fixed to the outer ring or the input shaft and faces the armature in the axial direction. It is possible to employ a rotor composed of a stationary member and an electromagnet that is supported by a stationary member and attracts the armature to the rotor by energization.

In order to solve the above problems, in the second invention, in the electric vehicle in which the drive source is only the electric motor and the driving force of the electric motor is transmitted to the wheels so that the vehicle travels, the driving force of the electric motor is reduced. The power transmission system for transmitting to the wheel has a driving wheel to which the driving force from the electric motor is input and a driven wheel for outputting the driving force transmitted from the driving wheel to the wheel side, and the rotational speed of the driving wheel Overrun that transmits the driving force of the driving wheel to the driven wheel when the speed is higher than the rotational speed of the driven wheel and causes the driving wheel to rotate freely when the rotational speed of the driven wheel becomes faster than the rotational speed of the driving wheel A configuration incorporating a type of one-way clutch was adopted.

In the electric vehicle according to the second aspect of the present invention, if the motor stops due to a failure when the vehicle is running, the one-way clutch automatically overruns when the rotational speed of the driven wheel exceeds the rotational speed of the driving wheel ( Idle state). For this reason, the wheels continue to rotate without being locked, and there is no possibility of being unable to steer or suddenly stopping the vehicle.

Here, in the electric vehicle equipped with ABS, when braking the wheel by ABS control, the rotation speed of the electric motor is lowered so as to be slower than the minimum value corresponding to the minimum rotation fluctuation of the wheel, or the ABS is stopped by stopping the electric motor. When the control is activated, the one-way clutch is idled and the power transmission system from the electric motor to the wheel is cut off, and the wheel can follow the ABS control well.

In the electric vehicle according to the second invention, the one-way clutch may be any of a roller type, a sprag type, a radial type ratchet type, or an axial type ratchet type.

Here, between the driving wheel and the driven wheel of the one-way clutch, a rotational resistance due to friction is imparted between the driving wheel and the driven wheel when the two wheels rotate relative to each other (at the time of idling). By providing a frictional resistance applying means in which the frictional torque due to the rotational resistance is made smaller than the allowable torque of the one-way clutch, even if the one-way clutch tries to idle due to the deceleration of the motor, the driving wheel and the driven wheel are driven by the frictional resistance applying means. Since constant torque transmission is performed between the two, energy regeneration can be performed using the electric motor as a generator.

A plurality of outer sides that are axially slidable against the inner periphery of the outer driving wheel located on the outer side of the driving wheel and the driven wheel that are fitted and arranged inside and outside as the frictional resistance applying means. A friction plate and a plurality of axially slidable inner friction plates that are prevented from rotating with respect to the outer periphery of the inner drive wheel are alternately assembled in the axial direction, and both friction plates are brought into elastic contact with each other by pressing of an elastic member. Or an outer cone whose outer peripheral surface is prevented from rotating on the inner periphery of the outer drive wheel and capable of sliding in the axial direction, and whose inner peripheral surface is tapered, and which is prevented from rotating on the outer periphery of the inner drive wheel. The inner cone whose outer peripheral surface is tapered to match the tapered inner peripheral surface of the outer cone, and the inner cone is urged toward the outer cone by an elastic member Ones can be adopted.

In the first invention, as described above, the two-way clutch is incorporated in the power transmission system from the motor to the wheel, and the engagement and disengagement of the two-way clutch are controlled by the electromagnetic clutch. Sometimes, power transmission from the motor to the wheels can be interrupted immediately. For this reason, it is possible to prevent the vehicle from being suddenly stopped due to the wheels being locked and being unable to steer.

Also, since the control of the two-way clutch is an electrical control that does not use hydraulic pressure, the configuration can be simplified.

Furthermore, it is possible to prevent the rotor of the electric motor from affecting the ABS control by disengaging the two-way clutch when braking the wheel by the ABS.

In the second invention, as described above, by incorporating an overrunning type one-way clutch in the power transmission system from the motor to the wheel, the power transmission from the motor to the wheel is immediately interrupted when the motor fails. can do. For this reason, it is possible to prevent the vehicle from being suddenly stopped due to the wheels being locked and being unable to steer. In addition, the one-way clutch does not require electrical control, so the structure is simple and the cost can be reduced.

Furthermore, when the wheel is braked by ABS control, the rotation speed of the motor is controlled so that the rotation speed of the motor becomes slower than the minimum value corresponding to the rotation fluctuation of the wheel. Therefore, when the ABS control is activated, the one-way clutch is in the idling state. Thus, the power transmission system from the electric motor to the wheel is cut off, and the wheel can follow the ABS control well.

Schematic plan view showing a first embodiment of an electric vehicle according to the present invention 1 is a longitudinal sectional view of a power interrupting device incorporated in the electric vehicle of FIG. Sectional view along line III-III in FIG. Sectional view along line IV-IV in FIG. Sectional drawing which shows the neutral state of the two-way clutch in a power interruption device Sectional drawing which shows the one-way engagement state of a two-way clutch Sectional drawing which shows the engagement state to the other direction of a two-way clutch Sectional drawing which shows the other example of the two-way clutch in a power interruption device Sectional view along line IX-IX in FIG. Sectional view along line XX in FIG. Sectional drawing which shows the standby state of the two-way clutch shown in FIG. Sectional drawing which shows the one-way engagement state of the two-way clutch shown in FIG. Sectional drawing which shows the engagement state to the other direction of the two-way clutch shown in FIG. Sectional drawing which shows the further another example of the two-way clutch in a power interruption device Sectional view along line XV-XV in FIG. Sectional drawing which shows the engagement state to the other direction of the two-way clutch shown in FIG. (A) thru | or (c) is a schematic plan view which shows the other example of a power interruption device incorporating. Schematic plan view showing a second embodiment of the electric vehicle according to the present invention (D) is a longitudinal sectional view of the one-way clutch incorporated in the electric vehicle shown in FIG. 18, and (e) is a sectional view taken along line XIX-XIX in (d). Sectional drawing which shows the other example of a one-way clutch Sectional drawing which shows another example of a one-way clutch Sectional drawing which shows another example of a one-way clutch (F) is a front view of the outer ring shown in FIG. 22, and (g) is a longitudinal sectional view of (f). (H) is a front view of the cam plate shown in FIG. 22, (i) is a plan view of (h). (J) is a development view showing a state where the engaging claw of the cam plate is engaged with the protrusion, and (k) is a development view showing a state where the engagement claw of the cam plate is released from the protrusion. Longitudinal sectional view of one-way clutch with built-in friction resistance applying means Longitudinal sectional view showing another example of frictional resistance applying means

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a first embodiment of an electric vehicle according to the present invention. As shown in the figure, a pair of left and right front wheels 2 are provided at the front of a vehicle body 1 in an electric vehicle, and a pair of left and right rear wheels 3 are provided at the rear.

An electric motor 10 is mounted on the front of the vehicle body 1, and the rotation of the electric motor 10 is changed by the transmission 11. The rotation of the output shaft of the transmission 11 is transmitted from the front differential 12 to the pair of left and right axles 4. The front wheel 2 rotates.

Here, the transmission 11 is adapted to shift the rotation of the electric motor 10 to one stage, but a transmission adapted to shift to two stages may be adopted.

Between the electric motor 10 and the transmission 11, a power interrupting device 20 that incorporates driving force transmission from the electric motor 10 to the transmission 11 and switching between interruptions is incorporated.

As shown in FIG. 2, the power interrupting device 20 includes a two-way clutch 21 and an electromagnetic clutch 40 that controls engagement and disengagement of the two-way clutch 21.

As shown in FIGS. 2 and 3, the two-way clutch 21 incorporates an input shaft 23 inside an outer ring 22 and is supported relatively rotatably by a bearing 24, and is provided at one end of the input shaft 23. A plurality of cam surfaces 27 are formed at equal intervals in the circumferential direction on the outer periphery of the cam ring portion 25 having a diameter and the cylindrical surface 26 formed on the inner periphery of the outer ring 22. The cage 28 provided between the outer ring 22 and the input shaft 23 is provided with a pocket 29 at a position facing the cam surface 27, and a roller 30 as an engaging member is incorporated in each pocket 29, and the input By rotating the shaft 23 and the cage 28 relative to each other, the roller 30 is engaged with the cylindrical surface 26 and the cam surface 27 so that the rotation of the input shaft 23 is transmitted to the outer ring 22.

Here, an input ring 31 to which rotation of the rotating shaft of the electric motor 10 shown in FIG. 1 is transmitted is fitted to the other end of the input shaft 23, and the input ring 31 and the input shaft 23 are fitted with a spline 32. It is designed to rotate together.

Further, a circular recess 33 is formed on one end surface of the cam ring portion 25 in the axial direction, and a switch spring 34 is incorporated in the recess 33. The switch spring 34 has a circular shape in which a part in the circumferential direction is cut off, and a pair of pressing pieces 35 are provided outward at both ends of the cut-off portion.

The pair of pressing pieces 35 is inserted into a notch 37 formed at one end of the retainer 28 from a notch 36 formed on the peripheral wall of the recess 33, and the notch 36 and the notch 37 are arranged in the circumferential direction. The cage 28 is elastically held in a neutral position where both ends are pressed in opposite directions and the roller 30 is disengaged from the cylindrical surface 26 and the cam surface 27 by the pressing.

As shown in FIG. 2, the electromagnetic clutch 40 has an armature 41, a rotor 42 that faces the armature 41 in the axial direction, and faces the rotor 42 in the axial direction, and attracts the armature 41 to the rotor 42 by energization. It consists of an electromagnet 43.

As shown in FIGS. 2 and 4, the armature 41 has an annular shape. The armature 41 is incorporated in a rotor guide 38 made of a non-magnetic material that is fitted into an end of the outer ring 22 on the opening side and is prevented from rotating around the outer ring 22, and is formed at the other end of the cage 28. It faces the orientation flange 28a in the axial direction.

The armature 41 is slidably fitted into a cylindrical portion 28b formed on the inner peripheral portion of the inward flange 28a, and a projecting piece 41a provided on the inner peripheral portion and a notch portion formed in the cylindrical portion 28b. It is prevented from rotating with respect to the retainer 28 by the engagement of 28c.

As shown in FIG. 2, the rotor 42 has a configuration in which

cylindrical portions

42 b and 42 c facing in the same direction are provided on the outer peripheral portion and the inner peripheral portion of the suction plate portion 42 a, and the outer peripheral cylindrical portion 42 b is fitted to the rotor guide 38. Combined and fixed to the rotor guide 38.

The electromagnet 43 includes an electromagnetic coil 43a and a core 43b that holds the electromagnetic coil 43a. The electromagnet 43 is supported by a support ring 44 as a stationary member, while the support ring 44 is supported by a bearing 45 incorporated between the outer ring 22 and a bearing 46 incorporated between the input ring 31 and the outer ring 22. The input ring 31 is rotatably supported.

The electric vehicle shown in the first embodiment has the above-described structure, and drives the motor 10 to energize the electromagnetic coil 43a of the electromagnetic clutch 40 when the vehicle starts moving forward.

When the electromagnetic coil 43 a is energized, the armature 41 is attracted to the rotor 42, and the cage 28 is coupled to the outer ring 22 via the armature 41 and the rotor 42.

On the other hand, by driving the electric motor 10, the rotation of the electric motor 10 is transmitted to the input shaft 23, and the input shaft 23 rotates in the direction indicated by the arrow in FIG. At this time, since the retainer 28 is coupled to the outer ring 22, the input shaft 23 and the retainer 28 rotate relative to each other, and as a result of the relative rotation, as shown in FIG. Engage with surface 27.

Therefore, the rotation of the input shaft 23 is transmitted to the outer ring 22 via the roller 30, the rotation of the outer ring 22 is changed by the transmission 11, and the rotation output from the transmission 11 is transmitted from the front differential 12 to the pair of left and right axles. 4 is transmitted to the front wheel 2 and the vehicle travels forward.

Generally, the vehicle is started at a low speed, but the accelerator pedal may be accidentally depressed strongly, and the depression of the pedal may be released immediately due to the surprise caused by the sudden start. At this time, the input shaft 23 is abruptly released after a large twist occurs.

At this time, the roller 30 is switched from the forward travel engagement position shown in FIG. 6 to the reverse travel engagement position shown in FIG. 7 until the engagement position is changed. Since the rotation direction backlash is large, release of twisting of the input shaft 23 can be absorbed by the rotation direction backlash. Therefore, the transmission of the shake-back vibration to the vehicle is suppressed, so that the driver does not feel uneasy or does not deteriorate the riding comfort.

When the electric motor 10 breaks down while the vehicle is traveling at high speed, the energization of the electromagnetic coil 43a of the electromagnetic clutch 40 is released.

Note that when the determination of failure of the electric motor 10, as shown in FIG. 1, the sensor S ₂ for detecting the rotational speed of the sensor S ₁ and the front wheel 2 for detecting the rotational speed of the rotary shaft of the electric motor 10 is provided, each sensor S _1, it is possible to determine the abnormality of the electric motor 10 from the comparison of the detection signal output from the S _2. An acceleration sensor that detects the acceleration of the rotating shaft of the electric motor 10 and the acceleration of the front wheel 2 can be provided, and abnormality of the electric motor 10 can be determined from comparison of detection signals output from the respective acceleration sensors.

As described above, when the energization of the electromagnetic coil 43a is canceled at the time of failure of the electric motor 10 during high speed traveling, the cage 28 is rotated with respect to the input shaft 23 by the restoring elasticity of the switch spring 34. As shown, the roller 30 is returned to the neutral position, and the two-way clutch 21 is immediately disengaged and the coupling between the outer ring 22 and the input shaft 23 is released.

For this reason, the front wheel 2 is not locked and cannot be steered. In addition, the vehicle does not stop suddenly, and the driver can perform an operation such as stopping the vehicle without his own panic.

In addition, after the stop, when the vehicle is manually moved to the side of the road, since the electric motor 10 and the front wheel 2 are separated, the electric motor 10 does not become a resistance, and the vehicle moves smoothly to the side of the road. Can be made.

Here, when the ABS is mounted on the electric vehicle, the energization to the electromagnetic coil 43a of the electromagnetic clutch 40 is released when the ABS is operated. As the energization is released, the two-way clutch 21 is switched to the disengaged state as described above, and the electric motor 10 and the front wheel 2 are disconnected. For this reason, even if the rotor of the electric motor 10 continues to rotate due to the inertia, the rotation is not transmitted to the front wheel 2 side. For this reason, the rotor of the electric motor 10 does not affect the ABS control, and the front wheel 2 can follow the ABS control well.

2 to 4, the cylindrical surface 26 is formed on the inner periphery of the outer ring 22 and the cam surface 27 is provided on the outer periphery of the cam ring portion 25, but the cylindrical surface is formed on the outer periphery of the cam ring portion 25, A cam surface may be provided around the circumference. In this case, a switch spring 34 is incorporated between the outer ring 22 and the cage 28 to elastically hold the cage 28 so that the roller 30 is held in the neutral position. Further, the rotor 42 of the electromagnet 43 is supported by the input shaft 23.

8 to 13 show another example of the two-way clutch 21 that forms the power interrupting device 20. In this example, the lengths of the pair of pressing pieces 35 provided at both ends of the switch spring 34 are made different, and the shorter pressing pieces 35a are opposed to each other in the circumferential direction of the notch 36 formed in the peripheral wall of the recess 33. The longer pressing piece 35b is engaged with the other end surface of the long hole 39 formed in one end of the retainer 28 in the circumferential direction, and the roller 30 is engaged when the vehicle moves forward. 2 is different from the two-way clutch 21 shown in FIG. 2 in that the cage 28 is elastically held in the standby state arranged at the position.

For this reason, the same parts as those of the two-way clutch 21 shown in FIG.

As described above, when the roller 30 of the two-way clutch 21 elastically holds the retainer 28 in a standby state arranged at the engagement position when the vehicle moves forward, when the electric motor 10 is driven for the vehicle to advance forward, Since the two-way clutch 21 is in the one-way clutch mode, the roller 30 is immediately engaged with the cylindrical surface 26 and the cam surface 27 by the rotation transmitted from the electric motor 10 to the input shaft 23, as shown in FIG. The rotation of the shaft 23 is transmitted to the outer ring 22 via the roller 30.

Further, the rotation of the outer ring 22 is immediately transmitted from the transmission 11 to the front wheel 2 via the front differential 12. For this reason, the vehicle can be started without a sense of incongruity.

Even if the electric motor 10 breaks down during high-speed traveling and the electric motor 10 is locked, the two-way clutch 21 is in the one-way clutch mode, and the outer ring 22 is shown with an arrow indicated by a dotted line in FIG. Therefore, the front wheel 2 is not locked and the vehicle travels with inertia.

For this reason, the driver can perform operations such as stopping by his / her own intention without falling into a panic, and after the vehicle stops, the vehicle can be smoothly moved to the side of the road by hand.

Here, in the forward start of the vehicle, when the depression of the pedal is immediately released after the rapid acceleration due to the rapid depression of the accelerator pedal, vibration due to the swing back is generated, but the two-way clutch 21 is in the one-way clutch mode. Since the vibration is transmitted only in one direction, the shake-back vibration can be effectively damped.

When an ABS is mounted on an electric vehicle, the rotational speed of the electric motor 10 is made much lower than the average speed of the front wheels 2 when the ABS is operating. As described above, the outer wheel 22 of the two-way clutch 21 is free to rotate with respect to the input shaft 23 by lowering the rotation speed of the electric motor 10 to be larger than the average speed of the front wheel 2, so that the front wheel 2 is rotated by the ABS control. By braking while fluctuating, the front wheel 2 is disconnected from the electric motor 10 and thus does not affect the ABS control.

In the traveling mode as described above, it is not necessary to energize the electromagnetic coil 43a of the electromagnet 43.

When moving the vehicle backward, the electric motor 10 is rotated in the reverse direction, and the electromagnetic coil 43a of the electromagnetic clutch 40 is energized.

On the other hand, the rotation of the electric motor 10 is transmitted to the input shaft 23 by driving the electric motor 10, and the input shaft 23 rotates in the direction indicated by the arrow in FIG. At this time, since the retainer 28 is coupled to the outer ring 22, the input shaft 23 and the retainer 28 rotate relative to each other, and as a result of the relative rotation, as shown in FIG. Engage with surface 27.

Therefore, the rotation of the input shaft 23 is transmitted to the outer ring 22 via the roller 30, the rotation of the outer ring 22 is changed by the transmission 11, and the rotation output from the transmission 11 is transmitted from the front differential 12 to the pair of left and right axles. 4 is transmitted to the front wheel 2 and the vehicle travels backward.

FIGS. 14 to 16 show still another example of the two-way clutch 21 forming the power interrupting device 20. In this example, a sprag 50 is used as an engagement element.

As shown in FIGS. 14 to 16, between the cylindrical surface 26 formed on the inner periphery of the outer ring 22 and the cylindrical surface 27a formed on the outer periphery of the cam ring portion 25 of the input shaft 23, the first cage 51 and its A second cage 52 is incorporated inside, and sprags 50 are incorporated in

pockets

53 and 54 formed in both

cages

51 and 52 and facing each other in the radial direction. A pair of elastic pieces 56 for urging the sprag 50 in the same direction as the rotation direction of the first holder 51 is incorporated in the pocket 53 of the first holder 51.

The sprag 50 is tilted by the relative rotation of both the

cages

51 and 52, and is engaged with the

cylindrical surfaces

26 and 27a of the outer ring 22 and the input shaft 23. In this case, the sprag 50 can be engaged in both the clockwise direction and the counterclockwise direction as shown in FIGS. 15 and 16. The use of the sprags 50 provides a large allowable torque even if it is compact because the number of the sprags 50 is larger than that in the case where the rollers 30 are used as the engagement elements.

In the case of FIG. 14, the second retainer 52 is fixed to the input shaft 23, and a switch spring 55 is incorporated between the second retainer 52 and the first retainer 51, so that the

pockets

53, 54 of both

retainers

51, 52 are included. The first cage 51 is urged in the circumferential direction in a direction in which the phase of the first shifts in the circumferential direction. As a result, the sprag 50 is inclined as shown in FIG. 15 to form a one-way clutch.

Here, an inward flange 51a is formed at the end of the first cage 51, and the armature 41 of the electromagnetic clutch 40 is slidably fitted to a cylindrical portion 51b provided on the inner peripheral portion of the inward flange 51a. And is prevented from rotating.

In the two-way clutch 21 configured as described above, when no current is flowing through the electromagnetic coil 43a, the one-way clutch is in a state as shown in FIG. 15, and the input shaft 23 rotates in the direction indicated by the arrow in FIG. The rotation is transmitted to the outer ring 22 through the sprag 50, and the outer ring 22 rotates in the same direction as the input shaft 23.

When the electromagnetic coil 43 a is energized, the armature 41 is attracted to the rotor 42, and the outer ring 22 and the first retainer 51 are integrated via the armature 41 and the rotor 42.

In this state, when the input shaft 23 is rotated in the direction opposite to the arrow shown in FIG. 15, the second cage 52 rotates relative to the first cage 51, and the sprag 50 rotates the input shaft 23 by the relative rotation. As shown in FIG. 16, it tilts in the direction opposite to the direction and engages with the cylindrical surface 26 of the outer ring 22 and the cylindrical surface 27 a of the input shaft 23, and transmits the rotation of the input shaft 23 to the outer ring 22.

In the sprag type two-way clutch shown in FIGS. 14 to 16, the first retainer 51 is urged toward one of the circumferential directions by the switch spring 55, and the sprag 50 is applied to each of the

cylindrical surfaces

26 and 27a. The first retainer 51 may be elastically held at the neutral position where the sprag 50 is disengaged from the

cylindrical surfaces

26 and 27a by the switch spring 55.

In the embodiment shown in FIG. 1, the power interrupting device 20 is incorporated between the electric motor 10 and the transmission 11, but the assembly position of the power interrupting device 20 is not limited to this.

FIGS. 17A to 17C show other examples of assembling the power interrupting device 20. In (a), a power interrupting device 20 is incorporated between the transmission 11 and the front differential 12.

(B) incorporates a power interrupting device 20 between each of the pair of left and right axles 4 and the front differential 12.

(C) incorporates a power interrupting device 20 between the pair of left and right axles 4 and the front wheels 2.

FIG. 18 shows a second embodiment of the electric vehicle according to the present invention. The second embodiment is different in that a one-way clutch 60 is used in place of the electric vehicle power interrupting device shown in FIG. For this reason, the same parts as those shown in FIG.

As shown in FIGS. 19D and 19E, the one-way clutch 60 is a driving wheel in which the rotation from the electric motor 10 is input to the inner side of the outer wheel 61 as a driven wheel that outputs rotational torque to the transmission 11. The inner ring 62 is incorporated and supported by a pair of bearings 63 so as to be relatively rotatable. A wedge space is formed on the outer periphery of the inner ring 62 with a cylindrical surface 64 formed on the inner periphery of the outer ring 61. A plurality of cam surfaces 65 are provided at intervals in the circumferential direction, and a roller 66 as an engagement member between each cam surface 65 and the cylindrical surface 64, and the roller 66 is engaged with both the cylindrical surface 64 and the cam surface 65. It is composed of an overrunning roller type that incorporates an elastic member 67 that urges in the direction of movement.

The one-way clutch 60 is incorporated so that the roller 66 engages the cylindrical surface 64 of the outer ring 61 and the cam surface 65 of the inner ring 62 when the electric motor 10 rotates in the direction in which the vehicle travels forward.

The electric vehicle shown in the second embodiment has the above structure. Now, when the electric motor 10 is driven, the rotation of the electric motor 10 is transmitted to the inner ring 62, and the inner ring 62 is in the direction indicated by the arrow in FIG. The roller 66 is engaged with the cylindrical surface 64 of the outer ring 61 and the cam surface 65 of the inner ring 62, and the one-way clutch 60 is engaged.

Therefore, the rotation of the inner ring 62 is transmitted to the outer ring 61 via the roller 66, the rotation of the outer ring 61 is shifted by the transmission 11, and the rotation output from the transmission 11 is transferred from the front differential 12 to the pair of left and right axles 4. Is transmitted to the front wheel 2 and the vehicle travels forward.

Generally, the vehicle is started at a low speed, but the accelerator pedal may be accidentally depressed strongly, and the depression of the pedal may be released immediately due to the surprise caused by the sudden start. At this time, various driving parts of the power transmission system from the electric motor 10 to the front wheels 2 are greatly twisted by the acceleration torque.

In particular, the rotor of the electric motor 10 has a large inertial force, and a large twist occurs in the output shaft connected to the rotor, and then the twist is abruptly released.

At this time, the inner ring 62 connected to the output shaft of the electric motor 10 is rotated in the direction opposite to the arrow shown in FIG. 19 (e), the roller 66 is displaced to the disengagement position, and the one-way clutch 60 is idled. By the idling, the twist of the output shaft of the electric motor 10 is released, and the vibration of shaking back is suppressed.

When the rotor support bearing of the motor 10 that generates a large amount of heat is burned due to poor lubrication, the battery power is lost, or there is an electrical short circuit when the vehicle is traveling at high speed, the motor 10 decelerates rapidly, or May lock.

At this time, the one-way clutch 60 is in an overrunning state in which the outer ring 61 to which the rotational torque from the front wheel 2 is transmitted rotates rapidly with respect to the inner ring 62, and the outer ring 61 rotates freely with respect to the inner ring 62.

For this reason, even if the electric motor 10 decelerates suddenly or locks, the vehicle will continue to coast and remain unsteerable. In addition, the vehicle does not stop suddenly, and the driver can perform an operation such as stopping the vehicle without his own panic.

Here, when the ABS is mounted on the electric vehicle, the rotational speed of the electric motor 10 is controlled so that the rotational speed of the electric motor 10 is slower than the average speed of the front wheels 2 when the ABS is operated. Alternatively, the electric motor 10 is stopped. Due to the speed control of the electric motor 10, the outer ring 61 of the one-way clutch 60 rotates quickly with respect to the inner ring 62, so that the one-way clutch 60 is in an idling state and power transmission from the electric motor 10 to the front wheel 2 is interrupted. Thus, the front wheel 2 can be accurately ABS controlled. Also, no abnormal noise is generated.

In the one-way clutch 60 shown in FIG. 19, the cylindrical surface 64 is formed on the inner periphery of the outer ring 61 and the cam surface 65 is provided on the outer periphery of the inner ring 62, but the cam surface is provided on the inner periphery of the outer ring 61. A cylindrical surface may be formed on the outer periphery. Further, although the inner ring 62 is a driving wheel and the outer ring 61 is a driven wheel, the outer ring 61 may be a driving wheel and the inner ring 62 may be a driven wheel.

FIG. 19 shows a roller type one-way clutch 60, but the one-way clutch 60 is not limited to this. 20 to 25 show other examples of the one-way clutch 60. FIG.

FIG. 20 shows a sprag type one-way clutch 60. In the sprag type one-way clutch 60,

cylindrical surfaces

73 and 74 are formed on the inner periphery of the outer ring 71 and the outer periphery of the inner ring 72, and two

retainers

75 and 76 having different outer diameters are provided between the

cylindrical surfaces

73 and 74. Built-in, a plurality of

pockets

77, 78 facing the

retainers

75, 76 in the radial direction are provided at intervals in the circumferential direction, and the sprags as engaging elements are straddling the

pockets

77, 78 facing the radial direction 79, and a pair of cam surfaces 80, 81 in which the distance between the opposing surfaces becomes longer as the sprag 79 is tilted toward one side in the circumferential direction is formed at both ends of the sprag 79, and the pocket of the small diameter side retainer 76 is formed. An elastic member 82 is incorporated in 78, and the sprag 79 is urged toward the direction in which the cam surfaces 80, 81 of the sprag 79 engage with the

cylindrical surfaces

73, 74.

In the one-way clutch 60, when the rotation of the electric motor 10 is transmitted to the inner ring 72 and the inner ring 72 rotates in the direction indicated by the arrow in FIG. 20, the cam surfaces 80 and 81 of the sprag 79 are connected to the outer ring side cylindrical surface 73 and the inner ring 72. The rotation of the inner ring 72 is transmitted to the outer ring 71 via the sprag 79, and the outer ring 71 rotates in the same direction as the inner ring 72.

When the rotation speed of the outer ring 71 exceeds the rotation speed of the inner ring 72, the sprag 79 is disengaged and the outer ring 71 rotates freely with respect to the inner ring 72.

In FIG. 20, the inner wheel 72 is a driving wheel and the outer wheel 71 is a driven wheel, but the inner wheel 72 may be a driven wheel and the outer wheel 71 may be a driving wheel.

FIG. 21 shows a radial type ratchet type one-way clutch 60. In this one-way clutch 60, an inner ring 112 is incorporated inside the outer ring 111, and a plurality of notches 113 are formed in the inner circumference of the outer ring 111 at intervals in the circumferential direction, while a plurality of pockets are formed on the outer circumference of the inner ring 112. 114 are provided at intervals in the circumferential direction, and an engaging claw 115 that can swing in each pocket 114 and an elastic member 116 that urges the engaging claw 115 in a direction to engage with the notch 113 are incorporated. Yes.

In the one-way clutch 60 configured as described above, one of the outer ring 111 and the inner ring 112 is used as a drive wheel to which power from the electric motor 10 is transmitted, and the other is used to output the driving force transmitted from the drive wheel to the wheel 2 side. Used as a driven wheel. When the inner ring 112 is used as a driving wheel and the inner ring 112 is rotated in the direction indicated by the arrow in FIG. 21 by driving the electric motor 10, the engaging claw 115 is engaged with the notch 113, and the rotation of the inner ring 112 is transmitted to the outer ring 111. The outer ring 111 rotates in the same direction as the inner ring 112.

When the rotation speed of the outer ring 111 exceeds the rotation speed of the inner ring 112 in the state of transmission of rotation from the inner ring 112 to the outer ring 111, the engagement claw 115 is disengaged and the outer ring 111 rotates freely with respect to the inner ring 112.

Here, if the number of the notches 113 is made larger than the number of the engaging claws 115 and the formation pitch of the notches 113 is different from the mounting pitch of the engaging claws 115, one of the plurality of engaging claws 115 is set. Since the engaging claw 115 is held in a state of being engaged with the notch 113, there is no play in the rotation direction, and the outer ring 111 can be rotated simultaneously with the rotation of the inner ring 112.

In FIG. 21, the engaging claw 115 is held by the inner ring 112 and the notch 113 is formed on the inner periphery of the outer ring 111, but the engaging claw 115 is held by forming a pocket on the inner periphery of the outer ring 111. A notch 113 may be formed on the outer periphery.

22 to 25 show an axial type ratchet type one-way clutch 60. FIG. In this one-way clutch 60, an inner ring 122 is incorporated inside the outer ring 121, an inward flange 123 is provided at one end of the outer ring 121, and the other end of the inner ring 122 is outwardly facing the inward flange 123 in the axial direction. A flange 124 is provided, and the inward flange 123 is provided with a plurality of projections 125 having cam surfaces 126 on the outer surface facing the outward flange 124 at equal intervals in the circumferential direction. The inward flange 123 and the outward flange A plurality of engaging claws 128 that can be engaged with the protrusions 125 are provided at equal intervals in the circumferential direction on the outer periphery of an annular cam plate 127 that is assembled between the opposing surfaces of the 124. The cam plate 127 is biased by an elastic member 129 made of a wave spring in a direction in which the cam plate 127 is engaged.

Here, the cam surface 126 formed on the outer periphery of the protrusion 125 is inclined with an upward gradient in the circumferential direction, as shown in FIGS. 23 (f), (g) and FIGS. 25 (j), (k). It consists of a surface 126a, a flat surface 126b that is continuous with the edge of the inclined surface 126a, and a step surface 126c that is continuous with the edge of the flat surface 126b. Further, the cam surface 126 is inclined radially outward with a downward gradient, and the inclination angle θ is about 4 °.

Further, the engaging claws 128 provided on the outer periphery of the cam plate 127 are inclined with respect to both the front and back surfaces of the cam plate 127 as shown in FIGS. The surface 126c can be engaged.

In the one-way clutch 60 configured as described above, one of the outer ring 121 and the inner ring 122 is used as a driving wheel to which power from the electric motor 10 is transmitted, and the other is used to output the driving force transmitted from the driving wheel to the wheel 2 side. Used as a driven wheel. When using the inner ring 122 as a driving wheel, when the inner ring 122 rotates in one direction by driving the electric motor 10, the engaging claw 128 engages with the step surface 126 c of the protrusion 125, and the rotation of the inner ring 122 is transmitted to the outer ring 121. Then, the outer ring 121 rotates in the same direction as the inner ring 122.

When the rotation speed of the outer ring 121 exceeds the rotation speed of the inner ring 122 in the state of transmission of rotation from the inner ring 122 to the outer ring 121, the engaging claw 128 moves in the circumferential direction along the cam surface 126, and the outer ring 121 moves to the inner ring 122. In contrast, it rotates freely.

Here, if the number of the protrusions 125 is larger than the number of the engaging claws 128 and the formation pitch of the protrusions 125 is different from the formation pitch of the engagement claws 128, among the plurality of engagement claws 128, Since one engagement claw 128 is disposed at a position that is in contact with or close to the step surface 126 c of the protrusion 125, there is little play in the rotation direction, and the outer ring 121 can be rotated simultaneously with the rotation of the inner ring 122.

22 to 25, the protrusion 125 is provided on the inward flange 123 of the outer ring 121, but the protrusion is provided on the outward flange 124 of the inner ring 122, and the cam plate 127 is directed toward the outward flange 124 by the elastic member 129. May be energized.

26, a large-diameter hole 85 is formed at the open end of the outer ring 61 in the roller-type one-way clutch 60 shown in FIG. 19, and the inner ring 62 has a large-diameter shaft at a position facing the large-diameter hole 85. A portion 86 is provided, and a frictional resistance applying means 90 is provided between the large diameter shaft portion 86 and the inner diameter surface of the large diameter hole portion 85.

Here, as the friction resistance applying means 90, a plurality of outer side friction plates 91 and a plurality of inner side friction plates 92 are alternately assembled in the axial direction, and the outer side friction plates 91 are attached to the inner diameter surface of the large-diameter hole 85. Thus, the inner side friction plate 92 is prevented from rotating around the inner ring 62 as a fitting by the spline 94 with respect to the large-diameter shaft portion 86. The

friction plates

91 and 92 are made to be slidable in the axial direction and are brought into elastic contact with each other by pressing of an elastic member 95 made of a disc spring, so that the outer friction plate 91 and the inner friction plate 92 are contacted with each other. A rotational resistance due to friction is applied between the outer ring 61 and the inner ring 62. Reference numeral 96 denotes a retaining ring for retaining the elastic member 95.

As described above, by providing the friction resistance applying means 90 including the plurality of

friction plates

91 and 92 between the outer ring 61 and the inner ring 62, even if the one-way clutch 60 idles due to the reduced rotation of the electric motor 10, the friction plates 91, Since 92 groups transmit the rotational torque by friction, the electric motor 10 functions as a generator and can regenerate energy.

The rotational torque due to the friction of the

friction plates

91 and 92 at the time of energy regeneration is set to be smaller than the driving torque of the electric motor 10, that is, the transmittable torque of the one-way clutch 60, and the outer side friction plate 91 at the time of fail safe when the electric motor 10 fails. And the inner friction plate 92 is set to slip.

Further, by providing the frictional resistance imparting means 90, when the acceleration is started by releasing the accelerator pedal and stopping the acceleration, the driving parts such as the output shaft of the electric motor that has been twisted by the acceleration torque as described above can be obtained. The vibration of shaking back is started, but the vibration can be effectively suppressed by the idling of the one-way clutch 60 and the resistance caused by the friction of the

friction plates

91 and 92.

Furthermore, the frictional resistance of the

friction plates

91 and 92 can be applied as a braking force when the ABS is operated.

In FIG. 26, the frictional resistance applying unit 90 includes a plurality of

friction plates

91 and 92, but the frictional resistance applying unit 90 is not limited to this. For example, as shown in FIG. 27, an outer cone 100 in which an inner peripheral surface 101 is tapered between a large diameter hole portion 85 and a large diameter shaft portion 86, and an outer peripheral surface 103 is a tapered inner peripheral surface of the outer cone 100. An inner cone 102 having a tapered shape that conforms to 101 is incorporated, and the outer cone 100 is fitted to the large-diameter hole 85 by a spline 93 to prevent the outer ring 61 from rotating, and the inner cone 102 is slidable in the axial direction. The nakone 102 is fitted to the large-diameter shaft portion 86 by the spline 94 so as to be prevented from rotating on the inner ring 62 and slidable in the axial direction, and the inner cone 102 is urged toward the outer cone 100 by pressing of the elastic member 104. It may be as described above.

In the second embodiment shown in FIG. 18, the one-way clutch 60 is incorporated between the electric motor 10 and the transmission 11, but the assembly position of the one-way clutch 60 is not limited to this. For example, you may make it integrate in the position of the power interruption apparatus 20 shown to Fig.17 (a) thru | or (c).

2 Front wheels
4 Axle 10 Electric motor 11 Transmission 12 Front differential (differential)
21 Two-way clutch 22 Outer ring 23

Input shaft

26,

27a Cylindrical surface

27, 65, 80, 81, 126 Cam surface 28

Cage

29, 53, 54, 77, 78, 114

Pocket

30, 66 Roller (engagement element)
34, 55 Switch spring 40 Electromagnetic clutch 41 Armature 42 Rotor 43 Electromagnet 50 Sprag (engagement element)
51 First cage 52 Second cage 60 One-way clutch 61, 71, 111, 121

Outer ring

62, 72, 112, 122

Inner ring

64, 73, 74

Cylindrical surface

67, 82, 116, 129

Elastic member

75, 76 Cage 79 Sprag 90 Friction resistance applying means 91 Outer side friction plate 92 Inner side friction plate 100 Outer cone 101 Inner peripheral surface 102 Inner cone 103 Outer peripheral surface 113

Notch

115, 128 Engagement claw 123 Inward flange 124 Outward flange 125 Protruding portion 126a Inclined Surface 126b Flat surface 126c Stepped surface 127 Cam plate 128 Engaging claw 129 Elastic member

Claims

In an electric vehicle in which the drive source is only an electric motor and the vehicle is driven by transmitting the driving force of the electric motor to wheels,
The power transmission system that transmits the driving force of the electric motor to the wheels has a retainer and an engagement member held by the retainer, and the driven side shaft and the driven body are engaged by engagement of the engagement member by rotation control of the retainer. A two-way clutch that couples to the side shaft, and an electromagnetic clutch that controls the engagement and disengagement of the two-way clutch by controlling the rotation of the cage by energization and interruption of the energization. Electric car.
The two-way clutch has a cylindrical surface on one of the inner periphery of the outer ring connected to the driven side shaft and the outer periphery of the input shaft connected to the driving side shaft, and the cylindrical surface on the other side. A plurality of cam surfaces are formed between the outer ring and the input shaft, and pockets are formed at positions facing the respective cam surfaces. In the pocket, a roller that engages with the cylindrical surface and the cam surface by the relative rotation of the outer ring and the input shaft is incorporated, and the outer ring and the input shaft between the member on the side where the cam surface is formed and the cage. 2. The electric vehicle according to claim 1, wherein the electric vehicle is of a roller type incorporating a switch spring for elastically holding the cage so that the roller is held in a neutral position.
The two-way clutch has a cylindrical surface on one of the inner periphery of the outer ring connected to the driven side shaft and the outer periphery of the input shaft connected to the driving side shaft, and the cylindrical surface on the other side. A plurality of cam surfaces are formed between the outer ring and the input shaft, and pockets are formed at positions facing the respective cam surfaces. In the pocket, a roller that engages with the cylindrical surface and the cam surface by the relative rotation of the outer ring and the input shaft is incorporated, and the outer ring and the input shaft between the member on the side where the cam surface is formed and the cage. The roller type of the present invention comprises a switch spring in which the roller is provided with rotational torque in a direction in which the roller is pushed into one narrow portion of the wedge space formed by the cylindrical surface and the cam surface. The described electric vehicle.
The two-way clutch is provided with a cylindrical surface on each of the inner periphery of the outer ring connected to the driven side shaft and the outer periphery of the input shaft connected to the driving side shaft. When the first retainer and the second retainer disposed inside the first retainer are assembled, and the two retainers are relatively rotated in the pockets provided at the opposing positions of the retainers. A sprag that engages with the respective cylindrical surfaces of the outer ring and the input shaft is incorporated, the second retainer is fixed to the input shaft, and the sprag is disposed between the first retainer and the second retainer and the cylindrical surface of the outer ring and The electric vehicle according to claim 1, comprising a sprag type incorporating a switch spring for biasing the first cage toward one circumferential direction in a direction engaging with the cylindrical surface of the input shaft.
The electromagnetic clutch is fixed to the outer ring or the input shaft and is opposed to the armature in the axial direction supported by the outer ring or the input shaft, and is supported by a stationary member. The electric vehicle according to claim 1, further comprising an electromagnet that attracts the armature to the rotor when energized.
A sensor for detecting the rotational speed of the rotating shaft of the electric motor and the rotational speed of the wheel is provided, and an abnormality of the electric motor is determined from a comparison of detection signals output from the sensors, and when the abnormality is determined, the electromagnetic coil of the electromagnet is detected. The electric vehicle according to claim 5, wherein energization is interrupted to disengage the two-way clutch.
An acceleration sensor for detecting the acceleration of the rotating shaft of the electric motor and the acceleration of the wheel is provided, and an abnormality of the electric motor is determined from a comparison of detection signals output from the respective acceleration sensors, and when the abnormality is determined, the electromagnetic coil of the electromagnet The electric vehicle according to claim 5, wherein energization is interrupted to disengage the two-way clutch.
The electric vehicle according to any one of claims 5 to 7, wherein when braking the wheel by ABS control, energization of the electromagnetic coil of the electromagnet is interrupted to disengage the two-way clutch when the ABS is operated. .
In an electric vehicle in which the drive source is only an electric motor and the vehicle is driven by transmitting the driving force of the electric motor to wheels,
In the power transmission system that transmits the driving force of the electric motor to the wheel, the driving wheel that receives the driving force from the electric motor and the driven wheel that outputs the driving force transmitted from the driving wheel to the wheel side, When the rotational speed of the driving wheel is faster than the rotational speed of the driven wheel, the driving force of the driving wheel is transmitted to the driven wheel, and when the rotational speed of the driven wheel becomes faster than the rotational speed of the driving wheel, the driving wheel An electric vehicle that incorporates an overrunning one-way clutch that rotates the wheel freely.
The one-way clutch is provided with a plurality of cam surfaces that form a cylindrical surface on one side of the inner periphery of the outer ring and the outer periphery of the inner ring that is incorporated inside the outer ring, and on the other side, a wedge space that forms a wedge space. A roller type that incorporates a roller between a cam surface and a cylindrical surface and an elastic member that urges the roller in a direction to engage both the cylindrical surface and the cam surface. One of the outer ring and the inner ring is a driving wheel. The electric vehicle according to claim 9, wherein the other is a driven wheel.
The one-way clutch forms a cylindrical surface on the inner periphery of the outer ring and the outer periphery of the inner ring incorporated inside, and forms a plurality of pockets in the circumferential direction of the cage assembled between the outer ring cylindrical surface and the inner ring cylindrical surface. The sprag is of a sprag type that incorporates a sprag in each pocket and an elastic member that urges the sprag in a direction to engage both the outer ring cylindrical surface and the inner ring cylindrical surface. One of the outer ring and the inner ring is a drive wheel. The electric vehicle according to claim 9, wherein the other is a driven wheel.
The one-way clutch is formed with a plurality of pockets spaced in the circumferential direction on one of the inner periphery of the outer ring and the outer periphery of the inner ring incorporated therein, and a plurality of notches provided in the circumferential direction on the other. A radial ratchet type incorporating an engaging claw swingable in the pocket and an elastic member that urges the engaging claw in a direction to engage the notch, and the outer ring and the inner ring The electric vehicle according to claim 9, wherein one is a driving wheel and the other is a driven wheel.
The one-way clutch is provided with an inward flange at one end of the outer ring, and an outward flange that is axially opposed to the inward flange is formed at the other end of the inner ring incorporated inside the outer ring. And a cam surface in which a flat surface is connected to the edge of the inclined surface inclined upwardly in the circumferential direction, and a step surface is connected to the edge of the flat surface. A plurality of protrusions having an outer periphery are provided in the circumferential direction, and the cam surface of each protrusion is inclined downwardly in the radial direction and is incorporated between the facing portions of the inward flange and the outward flange. An axial type in which a plurality of engaging claws that can be engaged with the stepped surface are formed on the outer periphery of the cam plate, and the cam plate is urged toward the flange on the side where the protrusion is formed by an elastic member. Ratchet type Rannahli, and the outer ring and one of the driving wheels of the inner ring, an electric vehicle according to claim 9 in which the other is a driven wheel.
Friction resistance imparting means for imparting rotational resistance due to friction between the driving wheel and the driven wheel between the driving wheel and the driven wheel of the one-way clutch in the radial direction is provided, The electric vehicle according to any one of claims 9 to 13, wherein the frictional torque of the frictional resistance applying means is smaller than the allowable torque of the one-way clutch.
The frictional resistance applying means includes a plurality of outer side friction plates slidable in the axial direction that are prevented from rotating with respect to an inner periphery of an outer driving wheel located on the outer side of the driving wheel and the driven wheel, and the inner side A plurality of inner side friction plates, which are axially slidable against the outer periphery of the drive wheel, are alternately assembled in the axial direction, and both friction plates are elastically contacted with each other by pressing of an elastic member. Item 15. The electric vehicle according to Item 14.
Outer cone in which the frictional resistance imparting means is prevented from rotating on the inner periphery of the outer driving wheel located on the outer side of the driving wheel and the driven wheel and is slidable in the axial direction, and the inner peripheral surface is tapered. And an inner cone whose outer periphery is prevented from rotating on the outer periphery of the inner drive wheel and is axially slidable and whose outer peripheral surface is tapered to match the tapered inner peripheral surface of the outer cone, and the inner cone is used as the outer cone. The electric vehicle according to claim 14, comprising an elastic member that presses toward the electric vehicle.
The electric vehicle according to any one of claims 14 to 16, wherein a regenerative braking force when the electric motor operates as a generator is smaller than a rotational resistance caused by friction of the frictional resistance applying means.
18. The motor according to claim 9, wherein when the wheel is braked by ABS control, the rotation speed of the electric motor is controlled so that the rotation speed of the electric motor becomes slower than the minimum value corresponding to the minimum rotation fluctuation of the wheel. Electric car.