JP2009296729A - Motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor which securely outputs braking torque even in a fail. <P>SOLUTION: The motor M includes a winding-side connector 5 having a plurality of winding-side terminals 4 connected in accordance with windings 3 of a plurality of phases in an armature and a circuit-side connector 8 having a plurality of circuit-side terminals 7 connected to a driving circuit 6 supplying current to the respective phase windings 3 and connecting the circuit-side terminals 7 and the winding-side terminals 4, which become pairs when they are coupled to the winding-side connector 5. The circuit-side connector 8 has a short-circuit means 9 shorting the respective phase windings 3 in the failure. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an improvement in a motor.

  In general, the motor is provided with a drive circuit for controlling the torque and the rotational speed regardless of the difference between DC and AC. As an example of the drive circuit, for example, when the motor M is configured as a three-phase brushless motor, the switching elements 71 and 72, the switching elements 73 and 74, and the switching elements 75 and 76 are respectively provided as shown in FIG. It is known that an arm 81, 82, 83 connected in series is connected to a power source E, and the switching elements 71, 72, 73, 74, 75, 76 in this drive circuit are controlled to open and close to a motor. By driving M, the output torque and rotation speed of the motor M can be controlled (see Patent Document 1).

  In addition, in an electromagnetic suspension device that generates a damping force by the torque of the motor, the torque is controlled by a drive circuit mounted on the motor to adjust the generated damping force and thrust of the electromagnetic suspension device to control the posture of the vehicle body. Things to do are known.

Specific examples of the electromagnetic suspension device include a ball screw nut, a screw shaft that is screwed to the ball screw nut, and a motor that is coupled to the screw shaft, and the ball screw nut and the screw shaft that are used when the shock absorber expands and contracts. Is converted into a rotational motion of the screw shaft, and the rotational motion of the screw shaft can be transmitted to the rotor of the motor, and the torque of the motor is controlled by the drive circuit to control the screw shaft and the ball screw nut. It is possible to generate a damping force that suppresses the relative motion in the axial direction and a thrust that actively promotes the relative motion (see, for example, Patent Document 2).
Japanese Patent Laying-Open No. 2003-324986 (paragraph number 0038, FIG. 4) JP 2003-104025 A (Detailed description of the invention, FIG. 4 and FIG. 17)

  By the way, when the current can be supplied to the motor, the output torque can be adjusted by the drive circuit, and the generated damping force and thrust of the electromagnetic suspension device can be controlled as intended. If the circuit cannot be supplied with current due to disconnection in the circuit or for other reasons, the motor cannot be actively driven to generate thrust to the electromagnetic suspension device, but the motor is forced by external input. Even if driven, the braking torque cannot be generated, and the electromagnetic suspension device may not be able to generate any damping force.

  Therefore, the present invention was devised to improve the above-described problems, and an object of the present invention is to provide a motor that can reliably output a braking torque even during a failure.

  In order to achieve the above object, a motor according to the present invention includes a winding-side connector having a plurality of winding-side terminals connected to each of a plurality of windings in an armature, and each phase winding. A motor having a plurality of circuit-side terminals connected to a drive circuit for supplying current to the motor, and a circuit-side connector that connects the winding-side terminals to each other when coupled to the winding-side connector The circuit-side connector has a short-circuit means for short-circuiting each phase winding at the time of failure.

  According to the motor of the present invention, at the time of failure when normal operation cannot be expected, the winding is short-circuited by the short-circuit means, so that a braking torque can be output for forced driving by an external input.

  And, since the short circuit means is not housed in the case of the motor, but has a circuit side connector that is attached to and detached from the case, it becomes difficult to be affected by the heat generated by the winding housed in the case, The thermal load on the short-circuit means can be reduced, and the reliability in the operation at the time of motor failure is improved.

  Furthermore, even when there is a break in the lead wire or the like arranged in the middle of the drive circuit and the winding, since the short-circuit means is arranged on the winding side, the winding can be reliably short-circuited. .

 Therefore, in this motor, the thermal load on the short-circuit means is reduced, and the winding can be reliably short-circuited by the short-circuit means at the time of failure, so that the braking torque can be reliably output at the time of failure. .

  The present invention will be described below based on the embodiments shown in the drawings. FIG. 1 is a diagram in which a motor according to an embodiment is applied to an electromagnetic suspension device. FIG. 2 is a perspective view of the motor. FIG. 3 is a diagram showing a short-circuit means in the motor.

  As shown in FIG. 1, the motor M in one embodiment is applied to an electromagnetic suspension device S. The electromagnetic suspension device S includes a motion conversion mechanism T that converts linear motion into rotational motion, and a motion conversion mechanism. The rotating side member at T is connected to the rotor 1 of the motor M.

  In the case of the electromagnetic suspension device S, the motion conversion mechanism T includes a screw shaft 10 and a ball screw nut 11 that is rotatably engaged with the screw shaft 10. The motion conversion mechanism T causes the ball screw nut 11 to rotate around the axis by linearly moving the screw shaft 10 in the axial direction, or conversely, by moving the ball screw nut 11 linearly in the axial direction. Is rotated around the axis to convert linear motion into rotational motion.

  In the electromagnetic suspension device S, one of the motion conversion mechanism T that exhibits the rotational motion of the screw shaft 10 or the ball screw nut 11 is connected to the rotor 1 of the motor M, and the motor M is driven to move. A thrust can be given to the other of the screw shaft 10 or the ball screw nut 11 of the conversion mechanism T so as to exhibit a linear motion, and the other motion of the screw shaft 10 or the ball screw nut 11 that tries to move linearly by an external input. Can be suppressed by the torque of the motor M. That is, the electromagnetic suspension device S not only exhibits a damping force that suppresses expansion and contraction due to external input, but can also expand and contract actively, and functions as an actuator and a shock absorber. When it is interposed between the sprung member and the unsprung member of the vehicle, it can function as an active suspension.

  As shown in the figure, the screw shaft 10 is connected to the rotor 1 of the motor M with the rotation side as a rotation side, the ball screw nut 11 is set as the linear motion side, and the ball screw nut 10 is held through the cylinder 18 that holds the ball screw nut 11 on the inner periphery. The screw nut 11 can be connected to an object of vibration suppression such as a sprung member or an unsprung member.

  Further, the motion conversion mechanism T is not limited to a feed screw mechanism composed of the screw shaft 10 and the ball screw nut 11, and other mechanisms such as a rack and pinion that can convert linear motion into rotational motion. The motor M may be connected to the rotor 1 through a transmission mechanism such as a speed reducer.

  Next, as shown in FIGS. 1 to 3, the motor M according to the embodiment includes a cylindrical case 2 that houses an armature and a field (not shown), and a rotor that is rotatably housed in the case 2. 1, a plurality of winding-side terminals 4 connected corresponding to each of the plurality of windings 3 in the armature, and a winding-side connector 5 that includes the winding-side terminals 4 and is attached to the case 2 A plurality of circuit side terminals 7 connected to a drive circuit 6 for supplying current to each phase winding 3, and a circuit side terminal 7 which forms a pair when the circuit side terminal 7 is contained and connected to the winding side connector 5. And a circuit side connector 8 for connecting the winding side terminal 4 and the short-circuit means 9.

  In the case of this motor M, it is configured as a brushless motor, the case 2 is formed in a cylindrical shape, holds a stator as an armature having a core around which the winding 3 is wound, and a field magnet. The rotor 1 having a magnet to be mounted on the outer periphery is rotatably accommodated, and one end of the rotor 1 protrudes from the lower end of the case 2 so as to be connectable to the motion conversion mechanism T.

  Further, a socket-like winding-side connector 5 is attached to the upper end side in FIG. 2, which is the end of the case 2 opposite to the protruding side of the rotor 1, and this winding-side connector 5 is connected to each phase. A winding side terminal 4 connected to the winding 3 is held inside.

  In the case of the motor M, the armature is provided with three-phase windings 3 of U, V, and W phases that are Y-connected, and the winding-side terminal 4 has 3 corresponding to the number of winding phases. Are provided at the bottom of the winding-side connector 5 and project inward of the winding-side connector 5. The winding 3 may be delta-connected.

  That is, in the case of the present embodiment, the motor M applies a sine wave voltage with a phase difference of 120 degrees to a three-phase winding of U, V, and W phases, for example, and rotates a rotating magnetic field to a stator that is an armature. This is configured as a conventionally known three-phase brushless motor in which a magnet serving as a magnetic field follows this and rotates the rotor 1. The number of windings is not limited to three phases. Further, in the case of the present embodiment, the motor M is configured as a brushless motor. However, the motor M may be a brushed motor having the armature as the rotor 1 and the field as the stator. The type and format are not limited to those illustrated.

  On the other hand, the drive circuit 6 is provided outside the case 2 and is not shown in detail. However, like the drive circuit of the prior art, the three arms in which two switching elements are connected in series are connected in parallel. It is a known drive circuit that connects the switching elements of the arm to the winding 3 of the motor M, and controls the generated torque and the number of rotations of the motor M by supplying current to each winding 3 by opening and closing the switching elements as appropriate. It can be done.

  Then, by connecting the three circuit side terminals 7 serving as the output terminals of the drive circuit 6 to the corresponding winding side terminals 4, current can be supplied to each of the windings 3. It is included in a circuit-side connector 8 that is set in a shape that can be inserted into the socket-shaped winding-side connector 5.

  Specifically, the circuit side terminal 7 has an arbitrary shape that can be connected to the winding side terminal 4, and is maintained in contact with the winding side terminal 4 by the connection of the circuit side connector 8 and the winding side connector 5. Thus, the circuit-side terminal 7 and the winding-side terminal 4 are in an intermediate state so that the winding 3 and the drive circuit 6 can be electrically connected. The circuit-side connector 8 can be detached from the winding-side connector 5 as well as being connected.

  Specifically, the circuit side terminal 7 is connected between the switching elements to each arm (not shown) of the drive circuit 6 via three lead wires 12, 13, 14 extending from the circuit side connector 8.

  In the case of this embodiment, when the winding side connector 5 and the circuit side connector 8 are connected, one side is a male shape and the other is a female shape. 5 and the circuit-side connector 8 only need to be realized, the shape and configuration are arbitrary, and the method of maintaining screw connection and other connection states can be adopted for maintaining the connection state.

  In turn, the short-circuit means 9 is included in the circuit-side connector 8. In this embodiment, the lead wires 12, 13, 14 provided in the circuit-side connector 8 and corresponding to the circuit-side terminals 7. Are connected between the circuit-side terminals 7 by connecting the in-connector wires 20, 21, 22, and the relays 15, 16 are closed when current supply is disabled. The circuit side terminals 7 are connected to each other by operating.

  Specifically, the relays 15 and 16 are controlled to be opened and closed by a relay driver 17 provided separately from the drive circuit 6, and when the current is supplied from the relay driver 17, the relays 15 and 16 are opened. Thus, the circuit side terminals 7 are kept disconnected from each other, and when the current supply from the relay driver 17 is interrupted, the circuit side terminals 7 are connected to each other.

  The relay driver 17 receives power supply from a power line common to the drive circuit 6. When the power supply is interrupted, the relay driver 17 can supply current to the windings from the drive circuit 6 to the relays 15 and 16. Thus, the relays 15 and 16 are closed.

  The relay driver 17 monitors information on the electrical angle of the rotor 1 and the current flowing in the winding 3 necessary for controlling the drive of the motor M by the drive circuit 6 detected by a sensor not shown. Even when an abnormality is recognized in these information with respect to the control by the drive circuit 6, the energization to the relays 15 and 16 is stopped and the relays 15 and 16 are closed. Specifically, for example, the difference between the current value flowing through the winding 3 of the motor M and the current value expected when the drive circuit 6 functions normally exceeds a preset threshold value for a predetermined time. When an abnormality is detected by a self-diagnosis of a current sensor or an electrical angle sensor, or when it is determined as an abnormality as a result of a self-diagnosis of a host control device (not shown) that sends a command to the drive circuit 6, the control system is If it is determined that there is an abnormality, the relay driver 17 stops energization of the relays 15 and 16.

  That is, the relays 15 and 16 are closed to connect the circuit-side terminals 7 to each other in the event of a failure in which current supply becomes impossible with respect to driving of the motor M or when an abnormality is recognized in the control. 3 is short-circuited.

  If the number of relays is set to a number obtained by subtracting 1 from the number of phases of the windings, the windings of all phases can be short-circuited. The relays 15 and 16 may employ a semiconductor relay using a semiconductor element in addition to an electromagnetic type in which the contact is driven by an electromagnet.

  Furthermore, since the relays 15 and 16 short-circuit the winding 3 that is an inductive load, an overvoltage may occur during the closing operation. Therefore, a varistor or the like that absorbs overvoltage may be provided to protect the relays 15 and 16 and the winding 3.

  As described above, when the motor M fails during normal operation, the winding 3 is short-circuited by the short-circuit means 9, and the electromagnetic suspension device S is thereby positively extended. However, when it is forced to expand and contract by an external input, the motor M exhibits a braking torque due to an induced electromotive force generated in the winding 3 that is short-circuited. Thus, it is possible to exhibit a damping force that suppresses expansion and contraction due to external input.

  In addition, the relays 15 and 16 in the short-circuit means 9 are not housed in the case 2 of the motor M, but the circuit-side connector 8 that is attached to and detached from the case 2 is provided. It becomes difficult to be affected by the heat generated by the wire 3, the thermal load on the short-circuit means 9 can be reduced, and the reliability of the operation of the motor M during the failure is improved.

  Furthermore, even when there is a break in the lead wires 12, 13, 14 and the like arranged in the middle of the drive circuit 6 and the winding 3, the short-circuit means 9 is arranged on the winding 3 side. The winding 3 can be reliably short-circuited, and fail safe can be realized.

  Therefore, in this motor M, the thermal load on the short-circuit means 9 is reduced, and since the winding 3 can be reliably short-circuited by the short-circuit means 9 at the time of failure, the braking torque is reliably output at the time of failure. Can do it.

  Therefore, the motor M is optimal for a motor as a damping force generation source of the electromagnetic suspension device S that is expected to stably generate a damping force.

  Further, even if no control abnormality occurs, the relays 15 and 16 short-circuit the winding of the motor M unless current is supplied. For example, when the motor M is used as a damping force generation source of the electromagnetic suspension device S, In a situation where the vehicle is loaded on a carrier car that carries the vehicle, even if the carrier car itself vibrates due to road surface unevenness while the carrier car is running, the electromagnetic suspension device S generates a damping force without supplying current. The vibration of the vehicle during loading can be suppressed, and the traveling of the carrier car can be stabilized.

  The circuit-side terminals 7 are connected to each other so as to short-circuit the three windings 3.

Further, when the short-circuit means 9 is incorporated in the case 2, if an abnormality is recognized in the short-circuit means 9, the main components (the armature including the rotor 1 and the winding 3, the field) fixed to the case 2 and the case 2 However, in the motor M of the present embodiment, since the short-circuit means 9 is provided in the circuit-side connector 8 that can be attached to and detached from the case 2, the short-circuit means 9 has an abnormality. If it is recognized, it is sufficient to replace the circuit side connector 8, which is advantageous in terms of economy.

  Further, since the relays 15 and 16 in the short-circuit means 9 are provided in the circuit-side connector 8, the relay driver 17 and the relays 15 and 16 are compared with the case where the short-circuit means 9 is incorporated in the case 2 of the motor M. There is also an advantage that it is not necessary to provide a terminal for connecting the case 2 to the case 2.

  This is the end of the description of the embodiment of the present invention, but the scope of the present invention is of course not limited to the details shown or described.

It is the figure which applied the motor in one embodiment to an electromagnetic suspension device. It is a perspective view of a motor. It is the figure which showed the short circuit means in a motor. It is a circuit diagram of the conventional motor drive circuit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotor 2 Case 3 Winding 4 Winding side terminal 5 Winding side connector 6 Drive circuit 7 Circuit side terminal 8 Circuit side connector 9 Short-circuit means 10 Screw shaft 11 Ball screw nuts 12, 13, 14 Lead wires 15, 16 Relay 17 Relay driver 18 Tube 20, 21, 22 Wiring in connector M Motor S Electromagnetic suspension device T Motion conversion mechanism

Claims (2)

Winding side connector having a plurality of winding side terminals connected corresponding to each of the windings of the plurality of phases in the armature, and a plurality of circuit sides connected to a drive circuit for supplying current to each phase winding In a motor provided with a circuit side terminal and a circuit side connector for connecting the winding side terminals to each other when connected to the winding side connector with a terminal, a short-circuit means for short-circuiting each phase winding at the time of failure A motor having a circuit-side connector. 2. The motor according to claim 1, wherein the short-circuit means includes a normally-closed relay installed between the circuit-side terminals, and connects the circuit-side terminals to each other when current supply becomes impossible.

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