JP2021081055A - Driving unit and electric power steering device - Google Patents

Abstract

To provide a driving unit which can transmit power to a driving object quickly even if failure occurs in a driving device or a power source which is mainly used, and to provide an electric power steering device.SOLUTION: A driving unit 10 includes a main driving device, an auxiliary driving device, a speed reducer 13, and a connection device 15. The main driving device has a first output shaft 11a which receives energy of a main driving source to rotate. The auxiliary driving device has a second output shaft 12a which receives energy of the main driving source or an auxiliary driving source to rotate. The speed reducer 13 has: an input shaft 16 connected with the first output shaft 11a; and an output rotating body 17 which outputs rotation having reduced speed to the outside. The connection device 15 connects the second output shaft 12a of the auxiliary driving device with the input shaft 16 or the first output shaft 11a when failure occurs in the main driving device.SELECTED DRAWING: Figure 2

Description

The present invention relates to a drive unit including a drive device and a speed reducer, and an electric power steering device.

As a vehicle steering device, a power steering device that assists a driver's steering operation by the force of an electric hydraulic system or an electric motor is known. The power steering device includes a steering mechanism that steers the wheels according to the operation of the steering unit (steering wheel), and a drive unit that outputs an assisting force according to the steering force applied to the steering unit to the steering mechanism.

In the case of an electric power steering device, the drive unit includes a motor that is an electric drive device and a speed reducer that reduces the output of the motor. The input shaft of the speed reducer is connected to the output shaft of the motor, and the output rotating body of the speed reducer can transmit power to the tie rod for wheel steering via a rack and pinion mechanism, a pitman arm, etc. ( For example, see Patent Document 1).

Japanese Unexamined Patent Publication No. 2013-35475

The drive unit used in the above-mentioned power steering device or the like cannot drive a drive target such as a steering mechanism when a failure occurs in the power supply system or the like of the drive device. Therefore, for example, when the drive unit is used in the power steering device, if the drive device fails, the steering operation by the driver becomes suddenly heavy.

The present invention provides a drive unit capable of quickly transmitting power to a drive target even when a failure occurs in a main drive device or a power source, and an electric power steering device.

The drive unit according to one aspect of the present invention includes a main drive device having a first output shaft that rotates by receiving the energy of the main drive source, and a second output shaft that rotates by receiving the energy of the main drive source or the auxiliary drive source. The auxiliary drive device having the above, the speed reducer having the input shaft to which the first output shaft is connected and the output rotating body for outputting the decelerated rotation to the outside, and the auxiliary drive when the main drive device fails. A connecting device for connecting the second output shaft of the device to the input shaft or the first output shaft is provided.

With the above configuration, in a situation where the main drive device operates normally, the second output shaft of the auxiliary drive device is in a cutoff state (a state in which power transmission is impossible) with respect to the input shaft of the speed reducer. In this state, the rotation of the first output shaft of the main drive device is input to the input shaft of the speed reducer, the rotation is decelerated, and the rotation is output from the output rotating body to the outside. Further, when some abnormality occurs in the main drive device or the power supply, the connecting device connects the second output shaft of the auxiliary drive device to the input shaft of the speed reducer or the first output shaft of the main drive device.

The input shaft of the speed reducer is arranged so as to penetrate the speed reducer main body of the speed reducer in the axial direction, and the main drive device is connected to one end side of the speed reducer body in the axial direction to be connected to the auxiliary drive device. May be arranged on the other end side of the speed reducer main body in the axial direction via the connecting device.

In this case, when some kind of failure occurs in the main drive device and the failure is detected by the failure detection sensor, the connecting device sets the second output shaft of the auxiliary drive device to the input shaft of the speed reducer in the center in the axial direction. Connecting. As a result, the driving force of the auxiliary driving device can be transmitted to the speed reducer.
When this configuration is adopted, the main drive device and the auxiliary drive device are arranged on both sides in the axial direction of the speed reducer so that power can be transmitted, so that the entire drive unit can be compactly configured. Further, in the case of this configuration, since the power of the auxiliary drive device is directly transmitted to the input shaft of the speed reducer, the power of the auxiliary drive device can be efficiently transmitted to the speed reducer.

The first output shaft of the main drive device is arranged so as to penetrate the device body of the main drive device in the axial direction, and the speed reducer is connected to one end side of the device body in the axial direction to drive the auxiliary drive. The device may be arranged on the other end side of the main body of the device in the axial direction via the connecting device.

In this case, when some kind of failure occurs in the main drive device and the failure is detected by the failure detection sensor, the connecting device sets the second output shaft of the auxiliary drive device to the first of the main drive device in the center in the axial direction. Connect to the output shaft. As a result, the driving force of the auxiliary drive device is transmitted to the input shaft of the speed reducer through the first output shaft of the main drive device.
When this configuration is adopted, the speed reducer and the auxiliary drive device are arranged on both sides in the axial direction of the main drive device so that power can be transmitted, so that the entire drive unit can be compactly configured. Further, in the case of this configuration, a structure for transmitting the rotation of the output rotating body of the speed reducer to the outside can be arranged at the axial end of the drive unit. Therefore, the degree of freedom in arranging the output rotating body and the external power transmission component is increased.

The drive unit of another aspect of the present invention has a main motor having a first output shaft that rotates by receiving the power of the main power supply, and a second output shaft that rotates by receiving the power of the main power supply or the auxiliary power supply. An auxiliary motor, an input shaft to which the first output shaft is connected, a speed reducer having an output rotating body that outputs the decelerated rotation to the outside, a failure detection sensor for detecting a failure of the main motor, and a failure detection sensor. When the failure detection sensor detects a failure of the main motor, it includes a connecting device for connecting the second output shaft of the auxiliary motor to the input shaft or the first output shaft.

With the above configuration, in a situation where the main motor operates normally, the second output shaft of the auxiliary motor is in a cutoff state (a state in which power transmission is impossible) with respect to the input shaft of the speed reducer. In this state, the rotation of the first output shaft of the main motor is input to the input shaft of the speed reducer, the rotation is decelerated, and the rotation is output from the output rotating body to the outside.
Further, when a failure occurs in the power system of the main motor and the failure is detected by the failure detection sensor, the connecting device sets the second output shaft of the auxiliary motor to the input shaft of the reducer or the first output of the main motor. Connect to the shaft. When the second output shaft of the auxiliary motor is connected to the input shaft of the speed reducer, the driving force of the auxiliary motor is directly transmitted to the input shaft of the speed reducer. When the second output shaft of the auxiliary motor is connected to the first output shaft of the main motor, the driving force of the auxiliary motor is transmitted to the input shaft of the reducer via the first output shaft of the main motor. ..

The connecting device receives the power of the auxiliary power source and receives the operation of the electromagnetic connection portion for connecting the second output shaft to the input shaft or the first output shaft by magnetic force and the operation of the electromagnetic connection portion. The second output shaft may be configured to have a mechanical connection portion that keeps the second output shaft connected to the input shaft or the first output shaft.

In this case, when the electromagnetic connection unit operates by receiving the electric power of the auxiliary power supply, the mechanical connection unit connects the second output shaft and the input shaft, or the second output shaft and the second output shaft are triggered by the operation of the electromagnetic connection unit. 1 The output shaft will be maintained in the connected state. As a result, even when the power of the auxiliary power source is consumed, the power of the auxiliary drive device can be transmitted to the speed reducer. Therefore, when this configuration is adopted, the size of the auxiliary power supply can be reduced.

The speed reducer includes a case block that rotatably holds the input shaft, and an annular output rotating body that is rotatably supported by the case block and has a plurality of pin grooves at equal intervals in the circumferential direction on the inner circumference. A plurality of internal tooth pins rotatably held in the pin groove of the output rotating body, a crankshaft rotatably supported by the case block, and the eccentric region swivels in response to the rotation of the input shaft, and the inside. A oscillating gear having a number of external teeth smaller than the number of tooth pins, and oscillating by receiving a turning force from the eccentric region of the crankshaft while engaging with the internal tooth pins by the external teeth. It may be configured.

In this case, the rotation input to the input shaft can be decelerated with high accuracy and output to the output rotating body.

The electric power steering device according to one aspect of the present invention includes a steering mechanism that steers the wheels according to the operation of the steering portion, and a drive unit that outputs an assisting force according to the operating force applied to the steering portion to the steering mechanism. The drive unit includes a main motor having a first output shaft that rotates by receiving the power of the main power supply, and an auxiliary motor having a second output shaft that rotates by receiving the power of the main power supply or the auxiliary power supply. A speed reducer having an input shaft to which the first output shaft is connected and an output rotating body that outputs the decelerated rotation to the outside, a failure detection sensor for detecting a failure of the main motor, and the failure detection sensor. Includes a connecting device that connects the second output shaft of the auxiliary motor to the input shaft or the first output shaft when a failure of the main motor is detected.

With the above configuration, in a situation where the main motor operates normally, the second output shaft of the auxiliary motor is in a cutoff state (a state in which power transmission is impossible) with respect to the input shaft of the speed reducer. In this state, the rotation of the first output shaft of the main motor is input to the input shaft of the speed reducer, the rotation is decelerated, and the rotation is output from the output rotating body to the steering mechanism as a helping force.
Further, when a failure occurs in the power system of the main motor and the failure is detected by the failure detection sensor, the connecting device sets the second output shaft of the auxiliary motor to the input shaft of the reducer or the first output of the main motor. Connect to the shaft. When the second output shaft of the auxiliary motor is connected to the input shaft of the speed reducer, the rotation of the auxiliary motor is directly transmitted to the input shaft of the speed reducer. The rotation is decelerated by the speed reducer, and is output from the output rotating body to the steering mechanism as an assisting force. When the second output shaft of the auxiliary motor is connected to the first output shaft of the main motor, the rotation of the auxiliary motor is transmitted to the input shaft of the speed reducer via the first output shaft of the main motor. The rotation is decelerated by the speed reducer, and is output from the output rotating body to the steering mechanism as an assisting force.

In the above-mentioned drive unit, when a failure of the main drive device is detected by the failure detection sensor, the power of the auxiliary drive device can be transmitted to the input shaft of the speed reducer, so that even if a failure occurs in the main drive device. , The power of the auxiliary drive device can be quickly transmitted to the drive target.

In the above-mentioned electric power swirling device, when a failure of the main motor is detected by the failure detection sensor, the power of the auxiliary motor can be transmitted to the input shaft of the speed reducer. The power of the decelerated auxiliary motor can be quickly transmitted to the steering mechanism as an auxiliary force.

The schematic block diagram of the electric power steering apparatus of an embodiment. Sectional drawing of the drive unit of 1st Embodiment. Sectional drawing of the drive unit of 2nd Embodiment.

Next, an embodiment of the present invention will be described with reference to the drawings.

<Electric power steering device>
FIG. 1 is a schematic configuration diagram of an electric power steering device 1 of a vehicle that employs the drive unit 10 (110) of the present embodiment.
The electric power steering device 1 includes a steering wheel 2 (steering portion), a steering shaft 3, a first gear box 4, a second gear box 5, and a steering mechanism 6. The steering wheel 2 is arranged in front of the driver's seat of the vehicle and is rotated by the driver. The steering shaft 3 is integrally connected to the steering wheel 2 and rotates integrally with the steering wheel 2.

The first gearbox 4 is connected to the lower end of the steering shaft 3, and outputs the decelerated rotation of the steering shaft 3 to the outside from the output unit 4a. The second gearbox 5 has a built-in drive unit 10, and outputs the rotation of the drive unit 10 (110) to the outside from the output unit 5a. The steering mechanism 6 includes a tie rod 6a for steering the left and right wheels w (front wheels) of the vehicle, and an operation arm 6b for transmitting an operating force to the tie rod 6a.

The operation arm 6b is composed of a pitman arm or the like, and one end side is connected to the output portions 4a and 5a of the first and second gearboxes 4 and 5, and the other end side is connected to the tie rod 6a. The operation arm 6b transmits the operation force output from the output units 4a and 5a of the first and second gear boxes 4 and 5 to the tie rod 6a as a force for steering the left and right wheels w.
In the present embodiment, the steering mechanism 6 is configured by the operation arm 6b, the tie rod 6a, and the like, but the steering mechanism 6 is not limited to this configuration, and the outputs of the first and second gear boxes 4 and 5 are each output. Other configurations may be used as long as the operating force of the portions 4a and 5a can be transmitted to the steering portions of the left and right wheels w.

The drive unit 10 (110) in the second gear box 5 includes an electric motor (main motor 11 and auxiliary motor 12 described later) which are drive devices. This motor receives a control signal from a control device (not shown) and transmits torque corresponding to the operation of the steering wheel 2 by the driver to the operation arm 6b through the output unit 5a. A sensor for detecting the operating force applied to the steering wheel 2 by the driver and the direction thereof is attached to the steering shaft 3. The control device receives the signal from the sensor and outputs a control signal corresponding to the operation of the steering wheel 2 to the motor.

<Drive unit of the first embodiment>
FIG. 2 is a diagram showing a cross section of the drive unit 10 of the first embodiment.
The drive unit 10 includes a main motor 11 (main drive device), an auxiliary motor 12 (auxiliary drive device), a speed reducer 13, a failure detection sensor 14, and a connection device 15. The main motor 11 is driven by receiving the electric power of the main battery 7 (main power source, main drive source) of the vehicle. The main motor 11 has a first output shaft 11a that rotates by receiving electric power. The auxiliary motor 12 is driven by receiving the electric power of the main battery 7 or the auxiliary battery 8 (auxiliary power source). The auxiliary motor 12 has a second output shaft 12a that rotates by receiving electric power.

The speed reducer 13 reduces the output rotation of the main motor 11 or the auxiliary motor 12 to a predetermined reduction ratio and outputs the output to the outside (output unit 5a of the second gearbox 5). The speed reducer 13 has an input shaft 16 to which the first output shaft 11a of the main motor 11 is connected, and an output rotating body 17 that outputs the decelerated rotation to the outside.

The failure detection sensor 14 detects, for example, a failure in the power supply system of the main motor 11. The detection signal of the failure detection sensor 14 is input to the control device 18 that controls the connection and disconnection of electric power to the auxiliary motor 12.

The connecting device 15 normally separates the second output shaft 12a of the auxiliary motor 12 from the input shaft 16 in the axial direction in the normal state (when the failure of the main motor 11 is not detected by the failure detection sensor 14). .. At this time, the second output shaft 12a of the auxiliary motor 12 is in a state in which power transmission is not possible with respect to the input shaft 16 of the speed reducer 13. Further, when the failure detection sensor 14 detects a failure of the main motor 11, the connection device 15 connects the second output shaft 12a of the auxiliary motor 12 to the input shaft 16 of the speed reducer 13.

The main motor 11 is an electric motor whose rotation direction and output of the first output shaft 11a are controlled by a control device (not shown). The main motor 11 includes an apparatus main body 11B in which a stator and a rotor (not shown) are housed in the case block 11c, and a first output shaft 11a that rotates integrally with the rotor in the case block 11c. The first output shaft 11a projects from the axial end of the device main body 11B toward one end side of the speed reducer 13 in the axial direction. At the end of the first output shaft 11a protruding from the device main body 11B, a fitting hole 19 is formed which is non-rotatably coupled to one end of the input shaft 16 of the speed reducer 13.

Like the main motor 11, the auxiliary motor 12 is an electric motor whose rotation direction and output of the second output shaft 12a are controlled by a control device (not shown). The auxiliary motor 12 includes an apparatus main body 12B in which a stator and a rotor (not shown) are housed in the case block 12c, and a second output shaft 12a that rotates integrally with the rotor in the case block 12c. The second output shaft 12a projects from the axial end of the device main body 12B toward the other end of the speed reducer 13 in the axial direction. A tapered hole 20 that can be connected to the other end of the input shaft 16 on the speed reducer 13 side is formed on the end surface of the second output shaft 12a protruding from the device main body 12B.

The speed reducer 13 is rotatably supported at the axial positions of the first case block 21A, the second case block 21B, the first case block 21A, and the second case block 21B fixed in the second gear box 5. The input shaft 16 is provided, a substantially cylindrical output rotating body 17 rotatably supported on the outer periphery of the first case block 21A and the second case block 21B via a bearing 22, and the first case block 21A and the second case block 21A and the second. A plurality of crankshafts 23 rotatably supported by the case block 21B, a first swing gear 24A that rotates together with two eccentric regions 23a and 23b of each crankshaft 23, and a second swing gear 24B. I have.
In the case of the present embodiment, the speed reducer main body of the speed reducer 13 is formed by the first and second case blocks 21A and 21B, the crankshaft 23, the first and second swing gears 24A and 24B, the output rotating body 17, and the like. It is configured.

The first case block 21A projects radially outward from the disk-shaped substrate portion 21Aa and the axially outer end of the substrate portion 21Aa (the end on the main motor 11 side), and then becomes cylindrical outward in the axial direction. It has an extending connecting flange portion 21Ab. The second case block 21B has a disk-shaped substrate portion 21Ba and a plurality of support column portions 21Bb extending in the direction of the first case block 21A from the axially inner end surface of the substrate portion 21Ba. The substrate portion 21Aa of the first case block 21A and the substrate portion 21Ba of the second case block 21B are formed to have the same outer diameter. In the second case block 21B, the end faces of the plurality of support columns 21Bb are overlapped with the end faces of the substrate portion 21Aa of the first case block 21A, and the support columns 21Bb are integrally connected to the substrate portion 21Aa by bolts 25. As a result, the first case block 21A and the second case block 21B form an integral case block.

Further, an input shaft 16 is rotatably supported via a bearing 35 at the axial center positions of the first case block 21A and the second case block 21B. The input shaft 16 penetrates the speed reducer main body in the axial direction. One end of the input shaft 16 penetrates the substrate portion 21Aa of the first case block 21A and projects in the direction of the main motor 11. The other end of the input shaft 16 penetrates the substrate portion 21Ba of the second case block 21B and projects in the direction of the auxiliary motor 12. In the present embodiment, the main motor 11 and the auxiliary motor 12 are coaxially arranged on both sides of the speed reducer 13.

An axial gap is secured between the substrate portion 21Aa of the first case block 21A and the substrate portion 21Ba of the second case block 21B by a plurality of support columns 21Bb. A first oscillating gear 24A and a second oscillating gear 24B are arranged in this gap.

The first oscillating gear 24A and the second oscillating gear 24B are formed with escape holes 26 through which each strut portion 21Bb of the second case block 21B penetrates. The relief hole 26 is formed to have a sufficiently large inner diameter with respect to the strut portion 21Bb so that each strut portion 21Bb does not interfere with the turning operation of the first swing gear 24A and the second swing gear 24B.

The output rotating body 17 is arranged so as to straddle the outer peripheral surface of the substrate portion 21Aa of the first case block 21A and the outer peripheral surface of the substrate portion 21Ba of the second case block 21B. The edge portions on both sides of the output rotating body 17 in the axial direction are rotatably supported on the outer peripheral surfaces of both substrate portions 21Aa and 21Ba via bearings 22. Further, on the inner peripheral surface of the central region of the output rotating body 17 in the axial direction (the region facing the outer peripheral surfaces of the first swing gear 24A and the second swing gear 24B), the rotation center axis c1 of the output rotating body 17 A plurality of pin grooves 27 extending in parallel with the above are formed. The plurality of pin grooves 27 are formed on the inner peripheral surface of the output rotating body 17 at equal intervals in the circumferential direction. A columnar internal tooth pin 28 is rotatably housed in each pin groove 27.

The first swing gear 24A and the second swing gear 24B are formed to have an outer diameter slightly smaller than the inner diameter of the output rotating body. External teeth 29 are formed on the outer peripheral surfaces of the first swing gear 24A and the second swing gear 24B in mesh with a plurality of internal tooth pins 28 arranged in the pin grooves 27 of the output rotating body 17. Has been done. The number of teeth of each external tooth 29 of the first oscillating gear 24A and the second oscillating gear 24B is set to be slightly smaller (for example, one less) than the number of internal tooth pins 28 (the number of pin grooves 27). ing.

The plurality of crankshafts 23 are arranged on the same circumference centered on the central axis of the first case block 21A and the second case block 21B. Each crankshaft 23 is rotatably supported by a first case block 21A and a second case block 21B via a bearing 30. The eccentric regions 23a and 23b of each crankshaft 23 penetrate the first swing gear 24A and the second swing gear 24B. The eccentric regions 23a and 23b are rotatably engaged with the support holes 31 formed in the first oscillating gear 24A and the second oscillating gear 24B via the eccentric bearing 32.
The two eccentric regions 23a and 23b of each crankshaft 23 are eccentric so that their phases are 180 ° out of phase with respect to the axis of the crankshaft 23.

When a plurality of crankshafts 23 receive an external force and rotate in one direction, the eccentric regions 23a and 23b of the crankshafts 23 rotate in the same direction with a predetermined radius, and accordingly, the first swing gear 24A and the second swing gear 24A and the second swing The gear 24B turns in the same direction with the same turning radius. At this time, the outer teeth 29 of the first swing gear 24A and the second swing gear 24B come into contact with each of the plurality of internal tooth pins arranged in the pin grooves 27 of the output rotating body 17 so as to mesh with each other.

In the speed reducer 13 of the present embodiment, the number of external teeth 29 of the first oscillating gear 24A and the second oscillating gear 24B is slightly smaller than the number of internal tooth pins 28 (the number of pin grooves 27). Since it is set, the output rotating body 17 is pushed around in the same direction as the turning direction by a predetermined pitch while the first swing gear 24A and the second swing gear 24B make one turn. As a result, the rotation of the crankshaft 23 is greatly decelerated, and the output rotating body 17 is rotated and output.
In the present embodiment, since the eccentric regions 23a and 23b of each crankshaft 23 are eccentric so as to deviate from each other by 180 ° around the axis, the turning phases of the first swing gear 24A and the second swing gear 24B are 180. It will be off by °.

Further, the end portion of each crankshaft 23 on the main motor 11 side penetrates the substrate portion 21Aa of the first case block 21A outward in the axial direction. A crankshaft gear 33 is attached to the end of the crankshaft 23 that protrudes outward from the board portion 21Aa. The tooth surface of the crankshaft gear 33 is meshed with an output gear 34 provided at the end of the first output shaft 11a of the main motor 11. Therefore, in the drive unit 10 of the present embodiment, the driving force of the main motor 11 is transmitted to the crankshaft 23 through the output gear 34 provided at the connecting portion between the first output shaft 11a and the input shaft 16.

A first connection block 36 is attached to the end of the case block 11c of the main motor 11 on the speed reducer 13 side so as to surround the circumference of the first output shaft 11a. The first connection block 36 is connected to the end surface of the connecting flange portion 21Ab of the first case block 21A of the speed reducer 13. As a result, the main motor 11 and the speed reducer 13 are integrally connected in a state where the first output shaft 11a and the input shaft 16 are connected. Further, the first connection block 36 and the connection flange portion 21Ab cover the periphery of the meshing portion between the first output shaft 11a (input shaft 16 of the reduction gear 13) and the output gear 34 in this state.

A second connection block 37 is attached to the end of the second case block 21B of the speed reducer 13 on the auxiliary motor 12 side so as to surround the other end of the input shaft 16. The second connection block 37 is formed in the shape of a thick disk having a through hole 38 in the center. A plurality of guide protrusions 39 extending in parallel with the axis of the second connection block 37 are projected from the end surface of the second connection block 37 on the auxiliary motor 12 side. On the end surface of the case block 12c of the auxiliary motor 12, a plurality of receiving holes 40 in which the guide protrusions 39 on the side of the second connection block 37 are slidably fitted are formed. The device main body 12B of the auxiliary motor 12 can be displaced forward and backward in the axial direction with respect to the speed reducer 13 by fitting the receiving hole 40 into the corresponding guide protrusion 39.

A locking flange 41 projecting outward in the radial direction is provided on the outer periphery of the end portion of the case block 12c of the auxiliary motor 12 on the speed reducer 13 side. On the other hand, a cylindrical wall 42 extending so as to surround the radial outer side of the locking flange 41 is projected on the outer periphery of the end portion of the second connection block 37 on the auxiliary motor 12 side. At the radial inner position of the base end of the cylindrical wall 42 of the ends of the second connection block 37 on the auxiliary motor 12 side, the base end of the clamp claw 43 having a substantially L-shaped cross section (one end portion having a substantially L-shape). ) Is rotatably attached. A plurality of clamp claws 43 are attached to the ends of the second connection block 37 on the auxiliary motor 12 side. Each clamp claw 43 is in a non-locking state (non-clamping state) with respect to the case block 12c of the auxiliary motor 12 while the auxiliary motor 12 is separated from the second connection block 37 by a predetermined distance or more in the axial direction. It is said that. On the other hand, when the auxiliary motor 12 approaches the second connection block 37 in the axial direction more than a predetermined distance, each clamp claw 43 rotates about the base end, and the back surface of the locking flange 41 of the case block 12c. Locked to (clamped). Reference numeral 44 in FIG. 2 is an urging member for urging the clamp claw 43 in the locking direction.

An urging member 45 for urging the auxiliary motor 12 in a direction away from the speed reducer 13 is interposed between the mutually opposite end faces of the second connection block 37 and the case block 12c in the axial direction. .. Further, a plurality of electromagnets 46 are embedded at positions inside the guide protrusion 39 of the second connection block 37 in the radial direction. On the other hand, a magnetic body 47 attracted by the electromagnets 46 is attached to a position of the end face of the case block 12c facing the plurality of electromagnets 46. In the present embodiment, the electromagnet 46 attracts the magnetic body 47 to displace the auxiliary motor 12 in the direction of the speed reducer 13 against the urging force of the urging member 45. The electromagnet 46 receives the electric power of the auxiliary battery 8 to generate a magnetic force.

Here, a tapered surface 48 is formed on the outer peripheral surface of the end portion of the input shaft 16 of the speed reducer 13 on the auxiliary motor 12 side so as to taper toward the tip side in the extension direction. The tapered surface 48 is formed substantially parallel to the inner peripheral surface of the tapered hole 20 formed in the second output shaft 12a of the auxiliary motor 12. The tapered surface 48 of the input shaft 16 is provided with respect to the inner peripheral surface of the tapered hole 20 of the second output shaft 12a while the auxiliary motor 12 is separated from the second connecting block 37 by a predetermined distance or more in the axial direction. It is in a non-contact state. At this time, the second output shaft 12a of the auxiliary motor 12 is not connected to the input shaft 16 of the speed reducer 13. On the other hand, when the auxiliary motor 12 approaches the second connection block 37 in the axial direction more than a predetermined distance by suction by the electromagnet 46, the tapered surface 48 of the input shaft 16 is frictionally connected to the inner peripheral surface of the tapered hole 20. To. At this time, the second output shaft 12a of the auxiliary motor 12 is connected to the input shaft 16 of the speed reducer 13.

Further, when the auxiliary motor 12 approaches the second connection block 37 in the axial direction more than a predetermined distance by attraction by the electromagnet 46, the clamp claw 43 held by the second connection block 37 causes the urging force of the urging member 44. The tip of the clamp claw 43 is locked to the locking flange 41 on the auxiliary motor 12 side. As a result, the second output shaft 12a and the input shaft 16 are mechanically maintained in a connected state.

In the present embodiment, the electromagnet 46 attached to the second connection block 37 constitutes the electromagnetic connection portion 15A of the connection device 15. Further, the clamp claw 43 attached to the second connection block 37 and the locking flange 41 on the auxiliary motor 12 side form a mechanical connection portion 15B of the connection device 15.

<Operation of the drive unit of the first embodiment>
In the situation where the main motor 11 operates normally, the electromagnet 46 is turned off, so that the second output shaft 12a of the auxiliary motor 12 is cut off from the input shaft 16 of the speed reducer 13 (separated state). It is said that. When the main motor 11 is energized by the control of the control device in this state, the first output shaft 11a of the main motor 11 rotates integrally with the input shaft 16 of the speed reducer 13. The rotation input to the input shaft 16 of the speed reducer 13 is decelerated by the speed reducer 13 and output from the output rotating body 17 to the output unit 5a of the second gearbox 5.

On the other hand, when the failure of the main motor 11 is detected by the failure detection sensor 14, the power of the auxiliary battery 8 is supplied to the electromagnet 46 under the control of the control device 18. As a result, the auxiliary motor 12 is displaced in the direction of the speed reducer 13 due to the attractive action of the electromagnet 46, and the second output shaft 12a of the auxiliary motor 12 is decelerated by frictional engagement between the inner peripheral surface of the tapered hole 20 and the tapered surface 48. It is coupled to the input shaft 16 of the machine 13. At this time, the mechanical connection portion 15B of the connection device 15 operates, and the connected state of the second output shaft 12a and the input shaft 16 is maintained. Further, at this time, the auxiliary motor 12 operates by receiving the electric power of the main battery 7 or the auxiliary battery 8. Specifically, the auxiliary motor 12 operates by receiving the power of the main battery 7 if there is no abnormality in the power supply system from the main battery 7, and if there is an abnormality in the power supply system from the main battery 7. , Operates by receiving the electric power of the auxiliary battery 8.

Further, in the drive unit 10, when a failure of the main motor 11 is detected by the failure detection sensor 14, the second output shaft 12a and the input shaft 16 are frictionally engaged with the inner peripheral surface of the tapered hole 20 and the tapered surface 48. Combined by. Therefore, even if the main motor 11 suddenly fails while the drive unit 10 is operating, the second output shaft 12a is input due to slippage between the inner peripheral surface of the tapered hole 20 and the tapered surface 48. The shaft 16 can be smoothly connected.

<Effect of the first embodiment>
In the drive unit 10 of the present embodiment, when a failure of the main motor 11 is detected by the failure detection sensor 14, the second output shaft 12a of the auxiliary motor 12 is connected to the input shaft 16 of the speed reducer 13 by the connecting device 15. Will be done. Therefore, even if the main motor 11 fails, the power of the auxiliary motor 12 can be quickly transmitted to the drive target.

Further, in the drive unit 10 of the present embodiment, the input shaft 16 of the speed reducer 13 is arranged so as to penetrate the speed reducer main body in the axial direction, and the main motor 11 is connected to one end side of the speed reducer main body in the axial direction. , The auxiliary motor 12 is arranged on the other end side of the speed reducer main body in the axial direction via the connecting device 15. The entire drive unit 10 can be compactly configured. Further, in the case of this configuration, since the power of the auxiliary motor 12 is directly transmitted to the input shaft of the speed reducer 13, the power of the auxiliary motor 12 can be efficiently transmitted to the speed reducer 13.

Further, in the drive unit 10 of the present embodiment, the connecting device 15 for connecting the second output shaft 12a to the input shaft 16 has an electromagnetic connection unit 15A, a mechanical connection unit 15B that operates triggered by the operation of the electromagnetic connection unit 15A, and the like. It has. Therefore, the operating time of the electromagnetic connection unit 15A can be shortened to reduce the consumption of the auxiliary battery 8, and even when the auxiliary battery 8 is consumed, the second output shaft 12a and the input shaft 16 are connected. Can be maintained in a state. Further, when this configuration is adopted, the consumption of the auxiliary battery 8 can be reduced, so that the auxiliary battery 8 can be downsized.

Further, the drive unit 10 of the present embodiment serves as a speed reducer 13 for decelerating the rotation of the main motor 11 and the auxiliary motor 12, and includes the first and second case blocks 21A and 21B, the output rotating body 17, the internal gear pin 28, and the crank. An eccentric swing type speed reducer equipped with a shaft 23, first and second swing gears 24A, 24B and the like is adopted. Therefore, the rotation input to the input shaft 16 can be decelerated with high accuracy and output to the output rotating body 17.

Further, in the electric power steering device 1 of the present embodiment, when a failure of the main motor 11 is detected by the failure detection sensor 14, the second output shaft 12a of the auxiliary motor 12 is changed to the input shaft 16 of the speed reducer 13 by the connection device 15. Therefore, even if a failure occurs in the main motor 11, the power of the decelerated auxiliary motor 12 can be quickly transmitted to the steering mechanism 6 as an assisting force.

<Drive unit of the second embodiment>
FIG. 3 is a diagram showing a cross section of the drive unit 110 of the second embodiment. In FIG. 3, the same reference numerals are given to the common parts with those of the first embodiment shown in FIG. In the following, description of common parts with the first embodiment will be omitted.
The drive unit 110 of the present embodiment includes a main motor 111 (main drive device), an auxiliary motor 12 (auxiliary drive device), a speed reducer 13, a failure detection sensor 14, and a connection device 15. The arrangement of the main motor 111, the auxiliary motor 12, and the speed reducer 13 is different from that of the first embodiment. That is, in the first embodiment, the main motor 11 and the auxiliary motor 12 are arranged on both sides of the speed reducer 13 in the axial direction, but the drive unit 110 of the second embodiment decelerates on both sides of the main motor 111 in the axial direction. The machine 13 and the auxiliary motor 12 are arranged.

More specifically, the first output shaft 111a of the drive unit 110 is arranged so as to penetrate the device main body 11B of the main motor 111 in the axial direction. The speed reducer 13 is arranged at one end side in the axial direction of the device main body 11B of the main motor 111, and the plurality of crankshaft gears 33 of the speed reducer 13 are located at one end portion of the first output shaft 111a of the main motor 111 in the axial direction. It is always in mesh. It is connected so that it cannot rotate relative to each other. Further, the auxiliary motor 12 is arranged on the other end side of the main motor 111 in the axial direction of the device main body 11B, and the second output shaft 12a of the auxiliary motor 12 is in the axial direction of the first output shaft 111a of the main motor 111. It is possible to connect to the end portion via the connecting device 15.
The speed reducer 13 of the present embodiment does not include the input shaft 16 of the first embodiment. In the speed reducer 13 of the present embodiment, the crankshaft gear 33 and the crankshaft 23 function as input shafts.

<Operation of the drive unit of the second embodiment>
In the situation where the main motor 11 operates normally, the electromagnet 46 is turned off, so that the second output shaft 12a of the auxiliary motor 12 is cut off (separated) from the first output shaft 111a of the main motor 111. State). When the main motor 111 is energized by the control of the control device in this state, the rotation of the first output shaft 111a of the main motor 111 is transmitted to the crankshaft 23 of the speed reducer 13. The rotation input to the crankshaft 23 of the speed reducer 13 is decelerated by the speed reducer 13 and output from the output rotating body 17 to an external driven member.

When the failure of the main motor 11 is detected by the failure detection sensor 14, the power of the auxiliary battery 8 is supplied to the electromagnet 46 under the control of the control device 18. As a result, the auxiliary motor 12 is displaced in the direction of the main motor 111 by the attractive action of the electromagnet 46, and the second output shaft 12a of the auxiliary motor 12 is mainly engaged by frictional engagement between the inner peripheral surface of the tapered hole 20 and the tapered surface 48. It is coupled to the first output shaft 111a of the motor 111. At this time, the mechanical connection portion 15B of the connection device 15 operates, and the connected state of the second output shaft 12a and the first output shaft 111a is maintained. Further, at this time, the auxiliary motor 12 operates by receiving the electric power of the main battery 7 or the auxiliary battery 8.

In this way, when the second output shaft 12a of the auxiliary motor 12 is coupled to the first output shaft 111a of the main motor 111, the rotation of the second output shaft 12a passes through the first output shaft 111a of the main motor 111 to reduce the speed reducer 13. Is input to the crankshaft 23 of. The rotation input to the crankshaft 23 is decelerated by the speed reducer 13, and is output from the output rotating body 17 to an external driven member.

<Effect of the second embodiment>
The drive unit 110 of the present embodiment is different from that of the first embodiment in the arrangement of the main motor 111, the auxiliary motor 12, and the speed reducer 13, but the other basic configurations and functions are almost the same. It has become. Therefore, when the drive unit 110 of the present embodiment is adopted, the same basic effect as that of the first embodiment described above can be obtained.

However, in the drive unit 110 of the present embodiment, the first output shaft 111a of the main motor 111 is arranged so as to penetrate the device main body 11B of the main motor 111 in the axial direction, and the speed reducer 13 is the device main body of the main motor 111. The auxiliary motor 12 is connected to one end side of the 11B in the axial direction, and the auxiliary motor 12 is arranged on the other end side of the device main body 11B of the main motor 111 in the axial direction via the connecting device 15. Therefore, the entire drive unit 110 can be compactly configured. Further, in the case of the drive unit 110 of the present embodiment, a structure for transmitting the rotation of the output rotating body 17 of the speed reducer 13 to the outside can be arranged at the axial end of the drive unit 110. Therefore, the degree of freedom in arranging the output rotating body 17 and the driven component can be increased.

The present invention is not limited to the above embodiment, and various design changes can be made without departing from the gist thereof.
For example, in each of the above embodiments, as the connecting device 15 for displacing the auxiliary motor 12, one provided with an electromagnetic connecting portion 15A using an electromagnet 46 and a mechanical connecting portion 15B using a clamp claw 43 is adopted. .. However, the form of the connecting device 15 is not limited to this, and various other forms can be adopted. Further, in the above embodiment, the connecting device 15 displaces the entire auxiliary motor 12 in the axial direction, but only the second output shaft 12a of the auxiliary motor 12 may be displaced in the axial direction.

Further, the speed reducer 13 of each of the above embodiments is a cylinder in which blocks (first and second case blocks 21A and 21B) that rotatably support the crankshaft 23 are fixed and internal tooth pins 28 are held on the inner circumference. Although the member is the output rotating body 17, conversely, a block in which a cylindrical member holding the internal tooth pin 28 is fixed to the inner circumference and the crankshaft 23 is rotatably supported may be used as the output rotating body.

Further, in each of the above embodiments, an electric motor is adopted as the main drive device and the auxiliary drive device, but the main drive device and the auxiliary drive device use the energy of a drive source other than electricity such as flood control. It is also possible to adopt.
Further, the application of the movable unit is not limited to the electric power steering device, and can be applied to various movable devices other than the electric power steering device.

1 ... Electric power steering device 2 ... Steering wheel (steering part)
6 ... Steering mechanism 7 ... Main battery (main power supply, main drive source)
8 ... Auxiliary battery (auxiliary power supply, auxiliary drive source)
10, 110 ... Drive unit 11 ... Main drive motor (main drive device)
11a ... 1st output shaft 11B ... Device body 12 ... Auxiliary motor (auxiliary drive device)
12a ... 2nd output shaft 13 ... Reducer 14 ... Failure detection sensor 15 ... Connection device 15A ... Electromagnetic connection 15B ... Machine connection 16 ... Input shaft 17 ... Output rotating body 21A ... 1st case block (case block)
21B ... Second case block (case block)
23 ... Crankshafts 23a, 23b ... Eccentric region 24A ... First swing gear (swing gear)
24B ... Second swing gear (swing gear)

Claims (7)

A main drive unit having a first output shaft that rotates by receiving the energy of the main drive source,
An auxiliary drive device having a second output shaft that rotates by receiving the energy of the main drive source or the auxiliary drive source.
A speed reducer having an input shaft to which the first output shaft is connected and an output rotating body that outputs the decelerated rotation to the outside.
When the main drive device fails, a connecting device that connects the second output shaft of the auxiliary drive device to the input shaft or the first output shaft, and
Drive unit equipped with. The input shaft of the speed reducer is arranged so as to penetrate the speed reducer main body of the speed reducer in the axial direction.
The main drive device is connected to one end side in the axial direction of the speed reducer main body.
The drive unit according to claim 1, wherein the auxiliary drive device is arranged on the other end side of the speed reducer main body in the axial direction via the connection device. The first output shaft of the main drive device is arranged so as to penetrate the device main body of the main drive device in the axial direction.
The speed reducer is connected to one end side in the axial direction of the device body.
The drive unit according to claim 1, wherein the auxiliary drive device is arranged on the other end side in the axial direction of the device body via the connection device. A main motor with a first output shaft that rotates by receiving the power of the main power supply,
An auxiliary motor having a second output shaft that rotates by receiving the electric power of the main power source or the auxiliary power source,
An input shaft to which the first output shaft is connected, and a speed reducer having an output rotating body that outputs the decelerated rotation to the outside.
A failure detection sensor that detects a failure of the main motor and
When the failure detection sensor detects a failure of the main motor, a connecting device that connects the second output shaft of the auxiliary motor to the input shaft or the first output shaft, and
Drive unit equipped with. The connecting device receives the power of the auxiliary power source and receives the operation of the electromagnetic connection portion for connecting the second output shaft to the input shaft or the first output shaft by magnetic force and the operation of the electromagnetic connection portion. The drive unit according to claim 4, further comprising a mechanical connection portion that keeps the second output shaft connected to the input shaft or the first output shaft. The speed reducer
A case block that rotatably holds the input shaft and
An annular output rotating body that is rotatably supported by the case block and has a plurality of pin grooves at equal intervals in the circumferential direction on the inner circumference.
A plurality of internal tooth pins rotatably held in the pin grooves of the output rotating body, and
A crankshaft that is rotatably supported by the case block and whose eccentric region rotates in response to the rotation of the input shaft.
An oscillating gear having a number of external teeth smaller than the number of internal tooth pins, and oscillating and rotating by receiving a turning force from the eccentric region of the crankshaft while engaging with the internal tooth pins by the external teeth.
The drive unit according to any one of claims 1 to 5. A steering mechanism that steers the wheels according to the operation of the steering unit,
A drive unit that outputs an assisting force according to an operating force applied to the steering unit to the steering mechanism is provided.
The drive unit
A main motor with a first output shaft that rotates by receiving the power of the main power supply,
An auxiliary motor having a second output shaft that rotates by receiving the power of the main power source or the auxiliary power source,
An input shaft to which the first output shaft is connected, and a speed reducer having an output rotating body that outputs the decelerated rotation to the outside.
A failure detection sensor that detects a failure of the main motor and
When the failure detection sensor detects a failure of the main motor, a connecting device that connects the second output shaft of the auxiliary motor to the input shaft or the first output shaft, and
Equipped with an electric power steering device.

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