JP6187823B2 - Electromagnetic suspension device - Google Patents

Description

  The present invention relates to an electromagnetic suspension device suitably used for buffering vibration of a vehicle such as an automobile.

  Generally, in a vehicle such as an automobile, a shock absorber is provided between a vehicle body (spring top) side and each wheel (spring bottom) side. As such a shock absorber, an electromagnetic suspension device using a linear motor (electromagnetic actuator) composed of a stator and a mover arranged so as to be capable of relative linear motion is known.

  Here, in the electromagnetic suspension device, for example, a coil (coil member) and a magnet (magnetic member) are provided in a coaxial inner cylinder and an outer cylinder that are interposed between a vehicle body and a wheel and can be relatively displaced. And an inverter (control means) that controls energization to the linear electromagnetic actuator (see, for example, Patent Document 1).

  In the electromagnetic suspension device according to Patent Document 1, the linear electromagnetic actuator is configured as a three-phase linear synchronous motor including three-phase (U-phase, V-phase, and W-phase) coils and magnets. And it is comprised so that the thrust (damping force) which generate | occur | produces with a linear electromagnetic actuator can be variably adjusted by controlling electricity supply to these three-phase coils with an inverter.

  On the other hand, each power line (power line) that connects the three-phase coil and the inverter is connected to each other via a relay. For example, when energization of the coil by the inverter is not performed or when the power line is disconnected, the relay is closed and the three-phase coil is short-circuited. At this time, the linear electromagnetic actuator can generate a resistance force as a damping force by an electromotive force generated in each coil due to the relative displacement between each coil and the magnet.

JP 2003-223220 A

  According to the prior art, for example, when a relay fails due to contact welding, depending on the connection state (circuit) formed by the welded contact, there is a possibility that heat generation due to overcurrent or relay failure may not be detected. For this reason, it is desired that safety and reliability can be ensured even when the relay fails.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide an electromagnetic suspension device that can improve safety and reliability.

  An electromagnetic suspension device according to the present invention includes a linear electromagnetic actuator interposed between a vehicle body and a wheel, and a control unit that controls energization of the linear electromagnetic actuator, the linear electromagnetic actuator being A coil member that is provided on one member of a coaxial inner cylinder or outer cylinder that is relatively displaceable and constitutes a three-phase motor, and a magnetic member that is provided on the other member and faces the coil member, When the coil member is energized, a propulsive force is obtained by an electromagnetic force generated between the coil member and when the coil member is de-energized, the coil member and the magnetic member are caused by relative displacement of the coil member. The damping force can be obtained by the electromotive force.

  In order to solve the above-described problem, a feature of the configuration adopted by the present invention is that the control unit and the coil of each phase of the coil member are connected by an independent cable, and the control unit and the coil member Among the three-phase independent cables provided between the two-phase cables, a relay is provided for each of the two-phase cables, and each of the relays has two contacts, a control contact and a short-circuit contact. The two-phase coil and each output part of the control means corresponding to the two-phase coil are connected, and a current flows from the control means to the two-phase coil, the short-circuit contact is the It is a contact that connects a coil of one phase and a coil of another phase of a two-phase coil and is connected to a cable not provided with the relay, and allows a current to flow between three-phase coils, Either the control contact or the short contact In addition, each of the relays includes a control contact and a short-circuit contact, and the control contact and the short-circuit contact are separated from each other and between the control contact and the short-circuit contact. When the energization of the operation coil constituting the relay is conducted, the short contact is brought into contact with the control contact by being guided to the magnetic body constituting the relay, and when not energized, by the spring force of the spring constituting the relay And a movable contact that comes into contact.

  According to the electromagnetic suspension device of the present invention, safety and reliability can be improved.

It is a block diagram at the time of control ON which shows the electromagnetic suspension apparatus by embodiment. It is a longitudinal cross-sectional view which shows a linear electromagnetic actuator. It is a perspective view which shows the relay assembly in which the relay was integrated. It is a side view at the time of control OFF which shows the relay by 1st Embodiment integrated in the relay assembly of FIG. It is explanatory drawing which shows the operation | movement of the relay at the time of control ON and control OFF for every state (normal, failure type) of a relay. It is a side view at the time of control OFF which shows the relay by 2nd Embodiment. It is a side view at the time of control OFF which shows the relay by 3rd Embodiment. It is a block diagram of the current command by a 4th embodiment. It is a characteristic diagram which shows an example of the time change of a control ON / OFF signal, the gain K, an electric current command (before correction | amendment, after correction | amendment), and a relay state.

  Hereinafter, an electromagnetic suspension device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings, taking as an example the case of application to a four-wheeled vehicle.

  1 to 5 show a first embodiment. In FIG. 1, an electromagnetic suspension device 1 is in parallel with a suspension spring (not shown) provided between a vehicle body (on a spring) and a wheel (under spring) constituting the vehicle, and the suspension spring. And a linear electromagnetic actuator 2 (hereinafter referred to as actuator 2) interposed between the vehicle body and the wheel, and an inverter 3 as control means for controlling energization of the actuator 2. In FIG. 1, a pair of actuators 2 and an inverter 3 are schematically illustrated. However, these actuators 2 and the inverter 3 include, for example, four wheels (left front wheel, right front wheel, left rear wheel, right rear wheel). A total of four sets are provided independently between the wheel) and the vehicle body.

  The inverter 3 is connected to a power source 5 of a vehicle such as a power storage device via a DC power line 4, and each is an actuator via a U-phase power line 6A, a V-phase power line 6B, and a W-phase power line 6C as cables. Two coil members 15 are connected. That is, the U-phase output unit 3A, the V-phase output unit 3B, and the W-phase output unit 3C of the inverter 3 are connected to the coil member 15 via the U-phase power line 6A, the V-phase power line 6B, and the W-phase power line 6C, respectively. It is connected to the constituent U-phase coil 15A, V-phase coil 15B, and W-phase coil 15C.

  The inverter 3 includes a plurality of switching elements such as transistors, field effect transistors (FETs), insulated gate bipolar transistors (IGBTs), and the like. Each switching element is opened and closed by a current from the arithmetic unit 7. It is controlled based on the command. When the actuator 2 is driven, the inverter 3 generates three-phase (U-phase, V-phase, W-phase) AC power from the DC power of the DC power line 4, and the actuator 2 (of the actuator 2) is connected via the power lines 6A, 6B, 6C. To the coil member 15).

  That is, the inverter 3 is supplied with electric power from the power source 5 through the DC power line 4, and based on the current command from the calculation unit 7, the actuator 2 (coil member 15) is connected to the actuator 3 through the power lines 6 A, 6 B, 6 C. Flow alternating current. As a result, the inverter 3 generates a thrust as a damping force in the actuator 2 and performs control to improve the riding comfort and steering stability of the vehicle body. In this control, based on the detection information of the vehicle sensor 8 attached to the vehicle, a current command corresponding to the damping force (target damping force) to be generated by the actuator 2 is calculated by the calculation unit 7, and the current command is converted to an inverter. This is done by outputting to 3.

  The vehicle sensor 8 includes, for example, sensors (detectors) that detect various state quantities of the vehicle such as an acceleration sensor, a wheel speed sensor, and a rudder angle sensor, and is connected to the calculation unit 7 via a sensor line 9. . The vehicle sensor 8 outputs a sensor signal serving as vehicle information to the calculation unit 7. The calculation unit 7 is configured using, for example, a microcomputer and is connected to the inverter 3 via a command line 10. The computing unit 7 outputs a command (current command, control ON / OFF command) to the inverter 3 based on the detection information of the vehicle sensor 8.

  Here, in addition to outputting a current command as a control command for improving riding comfort and improving steering stability to the inverter 3, the calculation unit 7 determines whether to perform control for improving riding comfort and improving steering stability. A control ON / OFF command as a command is output to the inverter 3. The control ON / OFF command is a command that determines whether or not to allow energization from the inverter 3 to the actuator 2 (coil member 15 thereof), that is, whether or not to control the damping force of the actuator 2 actively. Is.

  When a control ON command is output from the arithmetic unit 7 to the inverter 3, the inverter 3 determines whether or not the inverter 3 and the actuator 2 can be connected, that is, between the inverter 3 and the actuator 2 by relays 27 and 28 described later. Is determined based on a rule incorporated in the inverter 3 (control unit thereof). When it is determined that the electrical connection is allowed, the relay signal indicating that the inverter 3 and the actuator 2 (the coil member 15) are electrically connected to the relays 27 and 28 from the inverter 3 (the control unit thereof) Output through line 3D.

  Thereby, as shown in the circuit diagram (normal, control ON) at the upper right stage of FIG. 1 and FIG. 5 described later, the relays 27 and 28 conduct the inverter 3 and the actuator 2 (the coil member 15 thereof). In this state, the inverter 3 energizes the actuator 2 (the coil member 15 thereof) based on the current command from the calculation unit 7, and between the coil member 15 and a permanent magnet 26 (see FIG. 2) described later. A propulsive force that is a damping force is generated in the actuator 2 by the generated electromagnetic force. At this time, the inverter 3 variably adjusts the driving force (damping force) of the actuator 2 based on the current command from the calculation unit 7, thereby performing control for improving riding comfort and improving driving stability.

  On the other hand, when the control OFF command is output from the arithmetic unit 7 to the inverter 3, the inverter 3 determines whether or not the inverter 3 and the actuator 2 can be disconnected, that is, the relays 27 and 28 connect the inverter 3 and the actuator 2. Is determined based on the rules incorporated in the inverter 3 (control unit thereof). When it is determined that non-conduction is allowed, a relay signal indicating that the inverter 3 and the actuator 2 (coil member 15 thereof) are non-conductive is transmitted from the inverter 3 (control unit) to the relays 27 and 28. And output through the relay signal line 3D.

  Thereby, as shown in a circuit diagram (normal, control OFF) at the upper left stage in FIG. 5 described later, the relays 27 and 28 make the inverter 3 and the actuator 2 (the coil member 15) non-conductive. At this time, as will be described later, the relays 27 and 28 are switched to the connection positions that short-circuit the power lines 6A, 6B, and 6C of the actuator 2, that is, the coils 15A, 15B, and 15C of the coil member 15, and are closed. A circuit is formed. In this case, the actuator 2 can generate a resistance force as a damping force by the electromotive force generated in each coil 15A, 15B, 15C of the coil member 15 due to the relative displacement (stroke) between the coil member 15 and the permanent magnet 26. it can. That is, the actuator 2 can generate a damping force in accordance with the stroke speed without receiving external power supply, thereby enabling the vehicle to travel.

  Next, the configuration of the actuator 2 will be described with reference to FIG.

  The actuator 2 includes a stator 11 disposed on the vehicle body side and a mover 12 disposed on the wheel side. The stator 11 (coil member 15) and the mover 12 (permanent magnet 26) Constitutes a three-phase linear synchronous motor. That is, the actuator 2 is interposed between the vehicle body (sprung member) and the wheel (unsprung member), and the rod 16 corresponds to the inner cylinder of the coaxial inner cylinder and outer cylinder that can be relatively displaced. A cylinder comprising a coil member 15 (coils 15A, 15B, 15C) provided on the core 14 and a permanent magnet 26 as a magnetic member provided on the outer tube 22 corresponding to the outer cylinder and facing the coil member 15. Configured as a linear electromagnetic actuator. In addition, although illustration is abbreviate | omitted, the actuator 2 provides a coil member (coil) in the outer cylinder of the inner cylinder arrange | positioned radially inside, and the outer cylinder arrange | positioned radially outside, and is magnetic in an inner cylinder. It is good also as a structure which provides a member (permanent magnet).

  The stator 11 disposed on the vehicle body side is roughly constituted by an armature 13 and a rod 16. The armature 13 includes a core 14 made of a magnetic material, and a plurality of coils 15A, 15B, and 15C (a U-phase coil 15A, a V-phase coil 15B, and a W-phase coil 15C) that are provided on the core 14 and constitute a coil member 15. It is comprised by.

  The core 14 is formed by cutting or the like from, for example, a dust core, a laminated electromagnetic steel plate, or a magnetic piece, and the shape thereof is substantially cylindrical as a whole. On the other hand, each of the coils 15A, 15B, and 15C is wound in a predetermined direction and accommodated on the outer peripheral surface side of the core 14, and is disposed to face the inner peripheral surface of the mover 12 (permanent magnet 26 thereof). .

  Specifically, the coils 15 </ b> A, 15 </ b> B, and 15 </ b> C are disposed on the outer peripheral surface side of the substantially cylindrical core 14 and are disposed in the circumferential direction of the core 14, and are disposed at six positions in the axial direction of the core 14. They are spaced apart in the axial direction. Power lines 6A, 6B, 6C are connected to the coils 15A, 15B, 15C, and electric power is supplied from the inverter 3 via relays 27, 28 described later.

  The number of coils 15A, 15B, and 15C is not limited to that shown in the figure, and can be set as appropriate according to design specifications, such as three, nine, and twelve. Further, the six coils 15A, 15B, 15C adjacent in the axial direction are arranged so as to have a phase difference of 120 ° in electrical angle, for example. The wiring method between the coils 15A, 15B, and 15C can also be appropriately selected according to the voltage and current specifications on the power source 5 side, for example. The shape of the core 14 is not limited to that shown in the figure, and for example, a configuration for providing a convex portion for protecting a coil, a curved portion for reducing thrust pulsation, and the like may be employed.

  On the other hand, the rod 16 as an inner cylinder is formed in a substantially cylindrical shape, extends in the axial direction (left and right direction in FIG. 2) as a stroke direction, and the base end side (right end side in FIG. 2) is the inner side of the core 14. It is fixed (fitted) to. The tip end side (left end side in FIG. 2) of the rod 16 protrudes from a bearing mounting portion 22C of an outer tube 22 described later, and a threaded portion 16A attached to, for example, a sprung member (vehicle body side) of the vehicle is formed at the protruding end. Is provided. The guide rod 23 of the mover 12 is inserted inside the rod 16, and the inner peripheral surface on the proximal end side of the rod 16 is made of a sliding member such as a bearing or a sleeve that is in sliding contact with the outer peripheral surface of the guide rod 23. A first bearing 17 is provided.

  A stopper member 18 and a relay assembly 33 in which relays 27 and 28 to be described later are incorporated are attached to one end side (left end side in FIG. 2) of the outer peripheral surface of the rod 16 from the armature 13. The stopper member 18 comes into contact with the bearing mounting portion 22C of the outer tube 22 when the outer tube (yoke) 22 is fully extended, and is formed in a cylindrical shape by an elastic material such as polyamide resin, urethane resin, or rubber. . The stopper member 18 reduces the impact when contacting the bearing mounting portion 22C of the outer tube 22.

  On the other hand, the rod 16 is connected to three power lines 6A, 6B, and 6C connected to the coils 15A, 15B, and 15C, and a magnetic sensor (not shown) such as an MR sensor and a Hall IC sensor, for example. The two magnetic sensor wires 19 (see FIG. 3) and two temperature sensor wires 21 connected to the temperature sensor 20 are disposed. The temperature sensor 20 detects the temperature of the arbitrary coils 15A, 15B, 15C, and is provided (attached) on the inner peripheral side of the coils 15A, 15B, 15C. In the present embodiment, the number of temperature sensor lines 21 is two, but the number of temperature sensor lines 21 may be any number. On the other hand, the magnetic sensor is for detecting a magnetic pole position of the permanent magnet 26 described later (and thus a stroke position of the actuator 2). Although illustration is omitted, the magnetic sensor is provided, for example, closer to the armature 13 (between the relay assembly 33 and the armature 13) than the relay assembly 33 on the outer peripheral side of the rod 16. The power lines 6A, 6B, 6C and the sensor lines 19, 21 are drawn out through the rod 16.

  The mover 12 arranged on the wheel side constitutes a field, and is assembled to the stator 11 so as to be capable of relative displacement in the axial direction as the stroke direction. The mover 12 has an outer tube (yoke) 22 as an outer cylinder disposed on the outer peripheral side of the armature 13 (the core 14 and the coils 15A, 15B, and 15C), and is positioned on the inner side of the outer tube 22 in the stroke direction. And a plurality of permanent magnets 26 as magnetic members provided on the outer tube 22 and facing the coils 15A, 15B, 15C with a gap in the radial direction.

  The outer tube 22 is formed in a bottomed cylindrical shape using, for example, a magnetic material that forms a magnetic path when placed in a magnetic field, such as a carbon steel pipe for machine structure (STKM12A), and is arranged in an axial direction that is a stroke direction. It extends. That is, the outer tube 22 is made of a magnetic material, thereby forming a magnetic circuit of the actuator 22 and also serving as a cover for preventing the magnetic flux of the permanent magnet 26 described later from leaking to the outside.

  Here, the outer tube 22 has a cylindrical portion 22A extending in the axial direction, a bottom portion 22B that closes the other end side (right end side in FIG. 2) of the cylindrical portion 22A, and an opening side (one end side) of the cylindrical portion 22A. It is comprised by the bearing attachment part 22C which is located and protrudes in the radial direction inner side toward the rod 16 side of the stator 11 over the perimeter. Permanent magnets 26 are arranged in the axial direction inside the cylindrical portion 22A.

  The bottom portion 22B is provided with a guide rod 23 that is located inside the cylindrical portion 22A and extends from the bottom portion 22B to the inside of the armature 13 (inside the rod 16). The first bearing 17 provided in the rod 16 slides on the outer peripheral surface of the guide rod 23. The guide rod 23 is formed integrally with the outer tube 22 at the bottom 22B of the outer tube 22, or the guide rod 23 separate from the outer tube 22 is fixed to the bottom 22B using screws, bolts, or the like. A configuration can be employed.

  In addition, a mounting bracket 22D that is attached to an unsprung member (wheel side) of the vehicle is provided on the side of the bottom 22B of the outer tube 22 opposite to the guide rod 23. On the other hand, a second bearing 24 made of a sliding member such as a bearing or a sleeve that is in sliding contact with the outer peripheral surface of the rod 16 is provided on the inner peripheral surface of the bearing mounting portion 22C. In addition, a seal 25 that prevents water and dust from entering from the outside is provided on the inner peripheral side of the bearing mounting portion 22 </ b> C on one end side (the left end side in FIG. 2) from the second bearing 24.

  A plurality of annular permanent magnets 26 as magnetic members, which are members that generate a magnetic field, are arranged side by side along the axial direction on the inner peripheral surface side of the cylindrical portion 22A of the outer tube 22. In this case, the permanent magnets 26 adjacent in the axial direction have, for example, opposite polarities. For example, if the odd-numbered permanent magnets 26 counted from one end side (right side or left side) of the outer tube 22 are N poles on the inner peripheral surface side and S poles on the outer peripheral surface side, even numbers are counted from one end side. Each of the permanent magnets 26 has an S pole on the inner peripheral surface side and an N pole on the outer peripheral surface side.

  In this case, each permanent magnet 26 is, for example, a ring magnet integrally formed in a cylindrical shape, or a segmented segment magnet configured in an annular shape by arranging a plurality of arc-shaped magnet elements in the circumferential direction. Can do. The number of permanent magnets 26 is not limited to the illustrated example. That is, in the illustrated example, the number of permanent magnets 26 and the number of coils 15A, 15B, and 15C have an 11-pole 6-slot configuration, but may have a 4-pole 6-slot configuration or an 8-pole 6-slot configuration, for example.

  The outer tube (yoke) 22 is preferably a magnetic material from the viewpoint of a magnetic circuit and magnetic leakage, but at least one of the second bearing 24 and the bearing mounting portion 22C is preferably a non-magnetic material. The reason for this is as follows. That is, the magnetic flux emitted from the permanent magnet 26 has an inner peripheral surface S on the side facing the armature 13 (inner peripheral surface side) from the permanent magnet 26 having an N-pole inner peripheral surface through the core 14 of the armature 13. It becomes a path (magnetic path) toward the pole permanent magnet 26.

  On the other hand, on the side that does not face the armature 13 (outer peripheral surface side), the outer peripheral surface passes from the permanent magnet 26 with the N pole through the cylindrical portion 22A of the outer tube 22 and the outer peripheral surface goes to the permanent magnet 26 with the S pole. Road). Here, for example, when both the second bearing 24 and the bearing mounting portion 22C are made of a magnetic material, the magnetic flux emitted from the outer peripheral surface of the permanent magnet 26 on the most end side (left end side) of the outer tube 22 is the permanent magnet 26. A path (magnetic path) returning from the outer peripheral surface of the permanent magnet 26 to the inner peripheral surface of the permanent magnet 26 through the cylindrical portion 22A of the outer tube 22, the bearing mounting portion 22C, the second bearing 24, the rod 16, and the core 14 of the armature 13. Become.

  In this case, when the electromagnetic suspension device 1 is used, iron powder and sand iron from the road surface may adhere to the magnetic bearing mounting portion 22 </ b> C, the second bearing 24, and the rod 16. The iron powder and sand iron adhering in this way cannot be easily peeled off and may be caught in the sliding portion between the second bearing 24 and the rod 16. Therefore, if at least one of the second bearing 24 and the bearing mounting portion 22C is made of a non-magnetic material and the magnetic circuit is cut off, even if iron powder or sand iron adheres, it can be easily peeled off. The second bearing 24 and the rod 16 can be slid stably.

  Next, the relays 27 and 28 for switching between the “control ON (control)” state in which the control by the actuator 2 is performed and the “control OFF (short circuit, closed circuit)” state in which the control is not performed will be described.

  As described above, the output portions 3A, 3B, 3C of the respective phases of the inverter 3 and the coils 15A, 15B, 15C of the respective phases of the coil member 15 are independent of the U-phase power line 6A and the V-phase power line. 6B and W-phase power line 6C are connected. The relays 27 and 28 are two-phase cables among the three-phase independent cables provided between the inverter 3 and the coil member 15 (coils 15A, 15B, and 15C). In this embodiment, the U-phase power Line 6A and V-phase power line 6B are provided respectively. That is, in the embodiment, a two-phase cable provided with relays 27 and 28 is a U-phase power line 6A and a V-phase power line 6B, and a cable not provided with the relays 27 and 28 is a W-phase power line 6C.

  Here, of the relays 27 and 28, one relay 27 provided on the U-phase power line 6A is a first relay 27, and the other relay 28 provided on the V-phase power line 6B is a second relay. 28. The first relay 27 and the second relay 28 are provided in two of the three phases. In addition to the configuration provided in the U-phase power line 6A and the V-phase power line 6B, for example, the U-phase power line It can also be set as the structure provided in 6A and W phase power line 6C, or the structure provided in V phase power line 6B and W phase power line 6C.

  In each of the first relay 27 and the second relay 28, only two of the control contact 29 and the short-circuit contact 30 (a fixed contact 34 described later) and any one of the control contact 29 and the short-circuit contact 30 are connected. The movable contact 31 cannot be used. The control contact 29 of the first relay 27 connects the U-phase coil 15A and the U-phase output unit 3A of the inverter 3 corresponding to the U-phase coil 15A, and supplies the current from the inverter 3 to the U-phase coil 15A. It is a contact point that flows. On the other hand, the short-circuit contact 30 of the first relay 27 connects the U-phase coil 15A and the V-phase coil 15B, and is connected to the W-phase power line 6C where the relays 27 and 28 are not provided. This is a contact point for passing a current between 15B and 15C. For this purpose, the short-circuit contact 30 of the first relay 27 and the W-phase power line 6C are connected via a branch power line 6C1 branched from the W-phase power line 6C.

  The control contact 29 of the second relay 28 connects the V-phase coil 15B and the V-phase output part 3B of the inverter 3 corresponding to the V-phase coil 15B, and supplies the current from the inverter 3 to the V-phase coil 15B. It is a contact point that flows. On the other hand, the short-circuit contact 30 of the second relay 28 connects the V-phase coil 15B and the U-phase coil 15A, and is connected to the W-phase power line 6C where the relays 27 and 28 are not provided. This is a contact point for passing a current between 15B and 15C. For this reason, the short-circuit contact 30 of the second relay 28 and the W-phase power line 6C are also connected via the branch power line 6C1 branched from the W-phase power line 6C, similarly to the short-circuit contact 30 of the first relay 27. Has been.

  The movable contact 31 of the first relay 27 and the movable contact 31 of the second relay 28 are connected (contacted) to the control contact 29 and the shorted contact 30 (contacted) in accordance with a relay signal from the inverter 3. The state is switched to any one of the states. As a result, the first relay 27 and the second relay 28 have a structure in which only one of the control contact 29 and the short-circuit contact 30 can be connected.

  That is, as shown in the columns “Normal” and “Control ON” in FIGS. 1 and 5, the control unit 7 controls the first relay 27 and the second relay 28 via the inverter 3 (the control unit). When the ON relay signal is output, the first relay 27 and the second relay 28 are in a state where the movable contact 31 is connected (contacted) to the control contact 29, respectively. In this case, energization from the inverter 3 to the actuator 2 (the coil member 15) is performed based on the current command from the calculation unit 7. When the coil member 15 is energized, a propulsive force (attenuating force) can be obtained by an electromagnetic force generated between the coil member 15 and the ride comfort and steering stability can be controlled.

  On the other hand, as shown in the columns of “normal” and “control OFF” in FIG. 5, the control relay is switched from the calculation unit 7 to the first relay 27 and the second relay 28 via the inverter 3 (control unit thereof). When the signal is output, the first relay 27 and the second relay 28 are in a state where the movable contact 31 is connected (contacted) to the short-circuit contact 30. In this case, the power lines 6A, 6B, and 6C (the coils 15A, 15B, and 15C of the coil member 15) are short-circuited (a closed circuit is formed), and the energization from the inverter 3 to the coil member 15 is not performed. . During such non-energization, a resistance force (attenuating force) can be obtained by the electromotive force generated in the coil member 15 due to the relative displacement of the coil member 15 and the permanent magnet 26 (the stroke speed between the coil member 15 and the permanent magnet 26). A damping force can be generated according to

  Here, for example, consider the case where the U-phase contact has an ON failure (the control contact 29 of the first relay 27 has a welding failure). In this case, as shown in the column “U-phase ON failure” in FIG. 5, when “control OFF”, because the U-phase is connected to the control contact 29, the U-phase coil 15 </ b> A is connected to the U-phase of the inverter 3. It remains connected to the output unit 3A. At this time, since the V-phase coil 15B and the W-phase coil 15C are electrically connected via the short-circuit contact 30, the vehicle can be driven by the damping force generated by the counter electromotive force generated between the V-phase coil 15B and the W-phase coil 15C. It can be. On the other hand, when “control ON”, since the three phases are both electrically connected to the inverter 3, it is possible to perform control for improving riding comfort and steering stability. Thereby, the safety | security at the time of failure of the relay 27 is securable.

  Also, consider the case where the U-phase contact has an OFF failure (the short-circuit contact 30 of the first relay 27 has a welding failure or a disconnection failure of the operation coil 38 described later). In this case, as shown in the column of “U-phase OFF failure” in FIG. 5, when “control is OFF”, the three-phase coils 15A, 15B, and 15C are short-circuited. Can be generated. On the other hand, when “control ON”, the U phase is connected to the W phase via the branch power line 6C1 while being connected to the short-circuit contact 30. At this time, it is considered that the V phase and the W + U phase are connected between the inverter 3 and the actuator 2, and no current flows through the actuator 2 as instructed by the inverter 3. An abnormality can be detected by the sensor. Further, in this state, current is passed through the coils 15A, 15B, 15C of the actuator 2 (the output portions 3A, 3B, 3C of the inverter 3 are not connected to each other), so heat generation due to overcurrent can be prevented. Thereby, also from this aspect, safety at the time of failure of the relay 27 can be secured.

  That is, as shown in FIG. 5, in this embodiment, even when a welding failure occurs in the control contact 29 or the short-circuit contact 30 of the first relay 27 or the second relay 28, for example, the U-phase power line 6A Safety equivalent to a configuration in which a total of three relays are provided for each of the V-phase power line 6B and the W-phase power line 6C can be ensured. In this case, in the present embodiment, even if a failure of the relays 27 and 28 occurs, the structure does not cause heat generation due to overcurrent, and safety can be improved. In addition, in the present embodiment, the control of the power lines 6A, 6B, 6C for three phases and the switching of the short circuit can be performed by the two relays 27, 28, which is compared with the configuration in which three relays are provided. Thus, cost reduction, failure reduction, and reliability improvement can be achieved by downsizing and reduction in the number of parts.

  Next, a specific structure of each of the relays 27 and 28 will be described.

  As shown in FIGS. 2 and 3, each of the relays 27 and 28 is accommodated in a cylindrical relay case 32 and constitutes a relay assembly 33 together with the relay case 32. The relay assembly 33 is attached to the rod 16 constituting the stator 11 of the actuator 2. As a result, the relays 27 and 28 are built in the actuator 2.

  As shown in FIG. 3, three power lines 6A, 6B, 6C serving as magnet wires are drawn into the relay case 32 from the respective phase coils 15A, 15B, 15C of the coil member 15. Of these, U The phase power line 6A is connected to the first relay 27 (the movable contact 31 thereof), and the V phase power line 6B is connected to the second relay 28 (the movable contact 31 thereof). On the other hand, from the relay case 32, three power lines 6A, 6B, 6C serving as harnesses are drawn out toward the output portions 3A, 3B, 3C of the respective phases of the inverter 3. Further, the relay signal line 3D connected to the relays 27 and 28 is also drawn out from the relay case 32 toward the inverter 3.

  On the inner peripheral surface of the cylindrical relay case 32, recesses 32A that are recessed radially outward from the inner peripheral surface are provided at three positions spaced apart in the circumferential direction. Each of these recesses 32A serves as a relief groove for releasing wiring not directly related to the relays 27 and 28. In each recess 32A, a magnetic sensor wire 19 connected to a magnetic sensor (not shown) is provided. The temperature sensor line 21 connected to the temperature sensor 20 is inserted (passed).

  On the other hand, as shown in FIG. 4, each of the relays 27 and 28 accommodated in the relay case 32 is either a fixed contact 34 composed of a control contact 29 and a short-circuit contact 30, or a control contact 29 and a short-circuit contact 30. And a movable contact 31 that can only be connected. In FIG. 4, only one of the total of two relays of the first relay 27 and the second relay 28 is shown, but one relay shown in FIG. Are housed. Here, the relays 27 and 28 include a relay stator 35, a relay movable element 36, a spring 37, an operation coil 38, and a magnetic body 40.

  The relay stator 35 includes a base portion 35A, a pair of contact support portions 35B provided so as to protrude from the base portion 35A, and each contact support portion 35B of the base portion 35A is located on the opposite side across the operation coil 38. The spring mounting portion 35C is provided so as to protrude from the base portion 35A and to which one end of the spring 37 is attached. An insulator 35D that prevents the control contact 29 and the short-circuit contact 30 from conducting is provided between the pair of contact support portions 35B in the base portion 35A. An insulator 35E that prevents the control contact 29 and the operation coil 38 from conducting is provided between the operation coil 38 and the contact support portion 35B in the base portion 35A.

  A control contact 29 is provided on one contact support portion 35B on the side closer to the operation coil 38 of the pair of contact support portions 35B. On the other hand, a short-circuit contact 30 is provided on the other contact support portion 35 </ b> B on the side far from the operation coil 38. As a result, the control contact 29 serving as the fixed contact 34 and the short-circuit contact 30 are separated from each other.

  The relay mover 36 includes a contact support portion 36A disposed between the contact support portions 35B of the relay stator 35, and a spring attachment portion that is positioned between the spring 37 and the operation coil 38 and to which the other end of the spring 37 is attached. 36B, and a connecting portion 36C that connects the contact support portion 36A and the spring mounting portion 36B. The contact support portion 36 </ b> A is provided with a movable contact 31, whereby the movable contact 31 is provided between the control contact 29 and the short-circuit contact 30. On the other hand, a magnetic body 40 is provided on the opposite side of the spring mounting portion 35 </ b> C from the spring 37 so as to face the operation coil 38.

  The spring 37 is provided between the spring mounting portion 35C of the relay stator 35 and the spring mounting portion 36B of the relay movable element 36, and applies an elastic force in a direction away from each other to the spring mounting portions 35C and 36B. . That is, the spring 37 presses (biases) the relay movable element 36 in the direction in which the movable contact 31 and the short-circuit contact 30 are connected.

  The operation coil 38 is provided between the control contact 29 and the spring mounting portion 35 </ b> C in the base portion 35 </ b> A of the relay stator 35. The operation coil 38 displaces the relay movable element 36 in a direction in which the movable contact 31 and the control contact 29 are connected (contacted) by overcoming the spring force of the spring 37 by the magnetomotive force generated by energization and the magnetic force generated in the yoke 39. (Move). For this reason, the magnetic body 40 provided in the relay movable element 36 can have, for example, a magnetic force that repels a magnetic force generated in the yoke 39 when the operation coil 38 is energized. Accordingly, the movable contact 31 is brought into contact with the control contact 29 by being guided to the magnetic body 40 when the operation coil 38 is energized, and is brought into contact with the short-circuit contact 30 by the spring force of the spring 37 when not energized. .

  Here, the situation when the relays 27 and 28 break down will be examined.

  For example, when the operation coil 38 is energized, a large current flows between the inverter 3 and the actuator 2 and the control contact 29 is welded (when the control contact 29 and the movable contact 31 are fixed). By welding 29, it is possible to energize between the inverter 3 and the actuator 2. On the other hand, when the control contact 29 is welded and the control is OFF (the operation coil 38 is not energized), the movable contact 31 does not change from the control contact 29 to the short-circuit contact 30, so that the phase in which the relays 27 and 28 are broken can be short-circuited. First, the vehicle can be driven by the two-phase damping force of the three phases of the actuator 2.

  On the other hand, when the operation coil 38 is not energized, a large back electromotive force of the actuator 2 is generated and the short-circuit contact 30 is welded (when the short-circuit contact 30 and the movable contact 31 are fixed). When not energized, it is possible to generate a damping force corresponding to the counter electromotive force generated by the actuator 2 via the short-circuit contact 30. On the other hand, when the operation coil 38 is energized, the connection to the control contact 29 becomes impossible due to the welding at the short-circuit contact 30. For this reason, when the contacts are welded, a failure state in which the output portions 3A, 3B, 3C of the inverter 3 are short-circuited can be avoided, and heat generation due to overcurrent can be avoided.

  In such an embodiment, the control contact 29 and the short-circuit contact 30 can be switched by switching between energization / non-energization of the operation coil 38. In addition, it is possible to prevent the situation in which the control contact 29 and the short-circuit contact 30 are simultaneously connected or the control contact 29 and the short-circuit contact 30 are not connected structurally from occurring. In addition, once a failure occurs, the failure state can be mechanically held. As a result, the safety and reliability of the entire electromagnetic suspension device 1 including the actuator 2 and the inverter 3 can be improved. In the relay case 32, for example, hydrogen gas, cooling gas, insulating gas, or the like may be enclosed in order to prevent an arc generated when the contacts of the relays 27 and 28 are switched.

  The electromagnetic suspension device 1 according to the present embodiment has the above-described configuration, and the operation thereof will be described next.

  For example, when the actuator 2 of the electromagnetic suspension device 1 is interposed vertically between the sprung member (vehicle body side) and the unsprung member (wheel side) of the vehicle in a vertically placed state, the vehicle When the actuator vibrates upward and downward, a force acts on the actuator 2 in the stroke direction (axial direction). In accordance with this force, the stator 11 and the mover 12 move relative to each other. At this time, the damping force of the electromagnetic suspension device 1 can be adjusted by flowing a predetermined current through the coils 15A, 15B, and 15C according to the position of each permanent magnet 26, so that the ride comfort and control of the vehicle can be adjusted. Stability can be improved.

  Here, in the present embodiment, two relays 27 and 28 for switching between the control ON state in which the control by the actuator 2 is controlled and the control OFF state in which the control is not performed are provided between the actuator 2 and the inverter 3. Provided. In this case, the relays 27 and 28 short-circuit the control contact 29 for connecting the output portions 3A, 3B, and 3C of the inverter 3 and the three-phase coils 15A, 15B, and 15C and the three-phase coils 15A, 15B, and 15C. For this reason, only one of the short-circuit contacts 30 for connection can be connected.

  Therefore, the relays 27 and 28 can be switched between conductive and non-conductive between the inverter 3 and the three-phase coils 15A, 15B, and 15C by switching to the control contact 29 or the short-circuit contact 30. Thus, for example, even when the control contact 29 or the short-circuit contact 30 of the relays 27 and 28 has a welding failure or when the operation coil 38 is disconnected, the output portions 3A, 3B, and 3C of the inverter 3 are short-circuited. Can be prevented. As a result, the risk of heat generation due to overcurrent can be reduced even in a relay inoperable state, and the safety and reliability of the electromagnetic suspension device 1 can be improved.

  Moreover, in the relay inoperable state, it can be detected by, for example, a current sensor provided in the inverter 3 that current does not flow through the three-phase coils 15A, 15B, and 15C at the electrical angle as commanded by the inverter 3. For this reason, it is not necessary to add a new sensor or logic for confirming the operation of the relays 27 and 28, so that the cost can be reduced and the reliability of the inverter 3 and the actuator 2 can be improved. Further, the control of the power lines 6A, 6B, 6C for three phases and the switching of the short circuit can be performed by the two relays 27, 28. For example, as compared with the configuration having three relays, the electromagnetic suspension device 1 By reducing the overall size and reducing the number of parts, it is possible to reduce costs, reduce failures, and improve reliability.

  On the other hand, the movable contact 31 of each of the relays 27 and 28 comes into contact with the control contact 29 that becomes the fixed contact 34 based on the magnetic force generated by the operation coil 28 when the operation coil 38 is energized. Based on the force, the contact is made with the short-circuit contact 30 that becomes the fixed contact 34. For this reason, when the operation coil 38 is not energized, the three-phase power lines 6A, 6B, 6C are short-circuited (the three-phase coils 15A, 15B, 15C are short-circuited), and the damping force generated by the power generated by the actuator 2 ( The vehicle can be driven by the resistance force. When the operation coil 38 is energized, the three-phase coils 15A, 15B, 15C and the inverter 3 are connected, and the inverter 3 controls the energization of the actuator 2 to improve the ride comfort and steering stability of the vehicle. Can be controlled.

  In addition, when the relays 27 and 28 fail, for example, when the control contact 29 is welded, the vehicle can travel with the two-phase damping force of the three phases even if the operation coil 38 is de-energized. . On the other hand, when the short-circuit contact 30 is welded, even if the control by the inverter 3 is controlled ON, the failure state in which the output units 3A, 3B, and 3C of the inverter 3 are short-circuited can be avoided, and due to overcurrent. Heat generation can be suppressed. As a result, safety and reliability can be ensured even when the relays 27 and 28 fail.

  According to the embodiment, the relays 27 and 28 are built in the actuator 2. For this reason, even when the power lines 6A, 6B, 6C are disconnected between the inverter 3 and the actuator 2, the operation coils 38 of the relays 27, 28 built in the actuator 2 are de-energized, thereby The power lines 6A, 6B, and 6C can be short-circuited to generate a damping force (resistance force) in the actuator 2. Thereby, also from this aspect, the safety and reliability of the electromagnetic suspension device 1 can be improved.

  Next, FIG. 6 shows a second embodiment. A feature of the second embodiment resides in that an attractive force is generated between the yoke and the magnetic body in accordance with energization of the operation coil of the relay. In the second embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  The relays 27 and 28 include a relay stator 41, a relay movable element 42, a spring 43, an operation coil 44, and a magnetic body 46. FIG. 6 also shows only one of the total of two relays of the first relay 27 and the second relay 28 as in FIG. 4, but in the relay case 32, FIG. Two relays are accommodated.

  The relay stator 41 has a base 41A, a pair of contact support portions 41B provided so as to protrude from the base 41A, and each contact support portion 41B of the base 41A is located on the opposite side with the operation coil 38 interposed therebetween. A spring mounting portion 41C that protrudes from the base portion 41A and to which one end of the spring 43 is attached, and that protrudes between the spring mounting portion 41C and the contact support portion 41B and contacts the magnetic body 46 when the operating coil 44 is not energized. A stopper portion 41D that contacts and prevents displacement of the relay movable element 42 is formed. Insulators 41E and 41F are provided between the pair of contact support portions 41B of the base portion 41A and between the stopper portion 41D and the contact support portion 41B, respectively.

  A control contact 29 is provided on one contact support portion 41B that is closer to the operation coil 44 of the pair of contact support portions 41B. On the other hand, a short-circuit contact 30 is provided on the other contact support portion 41 </ b> B on the side far from the operation coil 44. As a result, the control contact 29 serving as the fixed contact 34 and the short-circuit contact 30 are separated from each other.

  The relay mover 42 is located between the contact support portion 42A disposed between the contact support portions 41B of the relay stator 41, the spring 43 and the stopper portion 41D, and the other end of the spring 43 is attached and magnetic. A spring mounting portion 42B on which the body 46 is provided and a connecting portion 42C that connects the contact support portion 42A and the spring mounting portion 42B. The contact support portion 42 </ b> A is provided with a movable contact 31, whereby the movable contact 31 is provided between the control contact 29 and the short-circuit contact 30.

  The spring 43 is provided between the spring mounting portion 41C of the relay stator 41 and the spring mounting portion 42B of the relay movable element 42, and imparts an elastic force in a direction away from each other to the spring mounting portions 41C and 42B. . That is, the spring 43 presses (bias) the relay movable element 42 in the direction in which the movable contact 31 and the short-circuit contact 30 are connected.

  The operation coil 44 is provided between the spring mounting portion 41C and the stopper portion 41D in the base portion 41A of the relay stator 41. The operation coil 44 displaces the relay mover 42 in the direction in which the movable contact 31 and the control contact 29 are connected (contacted) by overcoming the spring force of the spring 43 by the magnetomotive force generated by energization and the magnetic force generated in the yoke 45. (Move). That is, the magnetic body 46 is attracted by the magnetic force generated in the yoke 45 when the operation coil 44 is energized. Thereby, the movable contact 31 is brought into contact with the control contact 29 by being guided to the magnetic body 46 when the operation coil 44 is energized, and is brought into contact with the short-circuit contact 30 by the spring force of the spring 43 when not energized. .

  The second embodiment connects the movable contact 31 and the control contact 29 by attracting the magnetic body 46 based on energization to the operation coil 44 as described above (generating an attraction force) (control ON and ON). However, the basic operation is not particularly different from that according to the first embodiment.

  In particular, in the second embodiment, since an attractive force is generated between the operation coil 44 (the yoke 45) and the magnetic body 46 based on energization of the operation coil 44, the second embodiment is based on this attractive force. Thus, switching of the contacts (control contact 29, short-circuit contact 30) can be performed stably.

  Next, FIG. 7 shows a third embodiment. The feature of the third embodiment is that the capacity of the control contact is made larger than the capacity of the short-circuit contact. In the third embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  In FIG. 7, 51 indicates a control contact, and 52 indicates a short-circuit contact. In this case, the capacity of the control contact 51 is larger than the capacity of the short-circuit contact 52. In other words, the capacity of the short-circuit contact 52 is made smaller than the capacity of the control contact 51. Thereby, the increase in cost due to having a contact larger than the required capacity is suppressed, and the capacity of the contact is optimized.

  That is, it is necessary for the control contact 51 to pass the electric energy necessary for the control for improving the riding comfort and the steering stability from the inverter 3 to the actuator 2 (the coil member 15 thereof). When such control is ON, the actuator 2 may be in a substantially fixed state when control for improving steering stability is performed. In this case, since there is a situation where current flows in a concentrated manner in the coils 15A, 15B, and 15C of specific phases, the control contact 51 needs to have a contact capacity that takes them into consideration.

  On the other hand, the short-circuit contact 52 is only a current due to the counter electromotive force of the actuator 2 and is a current that is generated by the counter electromotive force when the actuator 2 is stroked. Unlike when the control is ON (when energization is controlled), there is no situation where current flows concentratedly in the coils 15A, 15B, and 15C of a specific phase. That is, since no back electromotive force is generated in the fixed state of the actuator 2, no current flows concentrated on the coils 15A, 15B, 15C of a specific phase. Therefore, in the present embodiment, the control contact 51 has a larger contact capacity than the short-circuit contact 52.

  The third embodiment is configured to have the control contact 51 having a large capacity and the short-circuit contact 52 having a small capacity as described above, and its basic operation is the same as that of the first embodiment described above. There is no particular difference.

  In particular, in the third embodiment, the capacity of the control contact 51 is larger than the capacity of the short-circuit contact 52. For this reason, the loss by the control contact 51 at the time of the control which flows a big electric current compared with the time of a short circuit reduces, and the risk that the control contact 51 will fail can be reduced. Thereby, the safety | security and reliability of the relays 27 and 28 can be improved. Further, the capacities of the control contact 51 and the short-circuit contact 52 can be optimized, and the costs of the relays 27 and 28 can be reduced.

  Next, FIG. 8 and FIG. 9 show a fourth embodiment. The feature of the fourth embodiment resides in that the current flowing through the coil of each phase is set to zero amperes when the relay contacts are switched. Note that in the fourth embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  The relays 27 and 28 may be shortened or welded depending on the ON / OFF timing, that is, the timing at which the movable contact 31 and the control contact 29 are in contact with each other or the timing at which they are not in contact with each other. . Specifically, when the relay is turned on / off (switched), depending on the timing (depending on the current at that time), an arc discharge may occur at the control contact 29. When an alternating current flows, the current fluctuates positively and negatively, so that the arc discharge disappears when the current value is near zero. However, when direct current is flowing, arc discharge continues until the distance between the contacts until the arc discharge disappears, and the contacts may be damaged during that time.

  In the case of the electromagnetic suspension device 1, depending on traveling conditions and control rules, there is a case where current is concentrated in the coils 15 A, 15 B, 15 C of a specific phase of the actuator 2, and in this case, direct current is supplied to the relays 27, 28. It can be equated with a state in which current flows continuously. In this case, if it overlaps with ON / OFF (switching) of the relays 27 and 28, the relays 27 and 28 may be damaged earlier and the life may be shortened. Therefore, in the present embodiment, when the contacts of the relays 27 and 28 are switched, that is, when the movable contact 31 comes into contact with the control contact 29 (when it comes into contact) and when it becomes non-contact (begins separating). )), The current flowing through the coils 15A, 15B, and 15C of each phase is set to zero ampere (0A).

  Here, FIG. 8 is a block diagram of a current command. If the current command output from the calculation unit 7 to the inverter 3 (the control unit) is the current command before correction, the inverter 3 (the control unit) uses the gain K to perform the actuator using the correction unit 61 shown in FIG. 2 (coil member 15) is actually energized, that is, a corrected current command is generated. FIG. 9 is a characteristic diagram (time history waveform) showing an example of the time change of the control ON / OFF signal, the gain K, the current command before correction, the current command after correction, and the state of the relays 27 and 28. ). As shown in FIG. 9, the current command before correction is output from the calculation unit 7 to the inverter 3 regardless of control ON / OFF. When the control is OFF, the gain K is fixed at zero, and the corrected current command is zero.

  Here, when the control ON / OFF signal changes from OFF to ON, the relays 27 and 28 are switched from the short-circuit contact 30 to the control contact 29, and the gain K is changed from zero to 1 during Δt. As a result, the current when switching from the short-circuit contact 30 to the control contact 29 can be reduced to zero ampere (0 A), and the current energization after the contact switching can be moderated. Thereby, the contact load of the relays 27 and 28 at the time of contact switching can be minimized, and the contact life can be extended and the reliability can be improved.

  The gain K is always zero when the control is OFF, and the gain K is changed from zero to 1 after switching the relays 27 and 28 from short circuit to control. In the present embodiment, the case where the gain K is linearly (linearly) changed from zero to 1 has been described as an example. However, the present invention is not limited to this. For example, another function or regularity may be provided.

  On the other hand, when the control ON / OFF signal changes from ON to OFF, the gain K is decreased from 1 to zero, and the relays 27 and 28 are switched from the control contact 29 to the short-circuit contact 30. In particular, the control contact 29 may be concentrated in a specific phase of the coils 15A, 15B, and 15C. In this case, the relays 27 and 28 are equivalent to a state in which a direct current flows. . At this time, when the relays 27 and 28 are switched from the control contact 29 to the short-circuit contact 30, arc discharge may continue for a long time. On the other hand, in the present embodiment, when the control ON / OFF signal changes from ON to OFF, the gain K is instantaneously set to zero, and after the gain K is set to zero, the relays 27 and 28 are connected from the control contact 29 to the short-circuit contact. Switch to 30. As a result, the current when switching from the control contact 29 to the short-circuit contact 30 can be reduced to zero amperes, and the contact can be protected, the service life can be extended, and the reliability can be improved.

  The fourth embodiment is configured to switch the contacts 29 and 30 in a state where the current is zero amperes by the correction unit 61 as described above, and the basic operation thereof is as described in the first embodiment. There is no particular difference from the form.

  In particular, in the fourth embodiment, when switching the contacts of the relays 27 and 28, the current flowing through the coils 15A, 15B and 15C of each phase is set to zero amperes (0A). For this reason, when switching the contacts 29, 30 of the relays 27, 28, current can be prevented from flowing through the relays 27, 28, and the load on the contacts 29, 30, 31 of the relays 27, 28 is minimized. Can do. As a result, the life of the relays 27 and 28 can be extended and the reliability can be improved.

  In the above-described fourth embodiment, when the control ON / OFF signal is turned OFF, the relay 27 and 28 are switched from the control contact 29 to the short-circuit contact 30 after the gain K is set to zero. Explained with an example. However, the present invention is not limited to this. For example, when an abnormal signal such as an emergency stop signal or an emergency stop signal is received from the arithmetic unit 7 or a higher-level vehicle-side control device (ECU, control unit), or from the inverter 3 instantaneously. When receiving a signal for shutting off the energization of the actuator 2 or the like, the relays 27 and 28 may be switched from the control contact 29 to the short-circuit contact 30 after the gain K is zero.

  In the above-described fourth embodiment, a case where the correction calculation for multiplying the current command by the gain K is performed by the inverter 3 (the control unit thereof) (the correction unit 61 is provided in the inverter 3) is taken as an example. explained. However, the present invention is not limited to this. For example, the calculation unit 7 may perform correction calculation (the correction unit 61 is provided in the calculation unit 7). In addition, the inverter 3 is provided with a criterion for determining whether or not the inverter 3 (control unit) may perform computation after receiving the control ON / OFF signal from the computation unit 7, and the relays 27 and 28 are set in accordance with the criterion. It is good also as a structure which switches.

  In the first embodiment described above, the operation coil 38 is provided in the relay stator 35 on the fixed contact 34 side (control contact 29 and short-circuit contact 30 side), and the magnetic material is provided on the relay mover 36 on the movable contact 31 side. The case where 40 is provided is described as an example. However, the present invention is not limited to this. For example, a magnetic body may be provided on the relay stator on the fixed contact side (control contact and short-circuit contact side), and the operation coil may be provided on the relay mover on the movable contact side. The same applies to the other embodiments.

  In each of the above-described embodiments, the linear electromagnetic actuator 2 is provided on the coil member 15 (coils 15A, 15B, 15C) provided on the rod 16 corresponding to the inner cylinder and the outer tube 22 corresponding to the outer cylinder. The case where the permanent magnet 26 (magnetic member) is used as an example has been described. However, the present invention is not limited thereto, and for example, a linear electromagnetic actuator may be configured by a coil (coil member) provided in the outer cylinder and a permanent magnet (magnetic member) provided in the inner cylinder. That is, the linear electromagnetic actuator can be composed of a coil member provided on one member of the inner cylinder or the outer cylinder and a magnetic member provided on the other member.

  In each of the above-described embodiments, the stator 11 is attached to the sprung member (for example, the vehicle body side) of the vehicle, and the movable member 12 is attached to the unsprung member (for example, the wheel side) of the vehicle. Explained. However, the present invention is not limited to this. For example, the stator may be attached to the unsprung member of the vehicle, and the mover may be attached to the sprung member of the vehicle.

  In each of the above-described embodiments, the case where the electromagnetic suspension device 1 is configured to be mounted on a vehicle such as an automobile in the vertical state has been described as an example. However, the present invention is not limited to this. It is good also as a structure attached to vehicles, such as a rail vehicle, in a standing state.

  In each of the above-described embodiments, the case where the electromagnetic suspension device 1 is configured to be mounted on a vehicle has been described as an example. However, the present invention is not limited to this, and for example, the electromagnetic suspension device 1 is used for various machines and buildings that serve as vibration sources. You may use for an electromagnetic suspension apparatus.

  Further, in each of the above-described embodiments, the linear motor having a circular cross section, that is, the case where the stator 11 and the mover 12 are formed in a cylindrical shape has been described as an example. However, the present invention is not limited to this, and for example, a linear motor having a cross-sectional shape other than circular, such as an I-shaped (flat plate), rectangular, or H-shaped linear motor, may be used. .

  According to the above embodiment, the safety and reliability of the electromagnetic suspension device can be improved.

  That is, according to the embodiment, each relay can be connected to either a control contact connected to the output unit of the control means (inverter) or a short-circuit contact that short-circuits the three-phase coil. Therefore, each relay can be switched between conduction and non-conduction between the control means and the three-phase coil by switching to a control contact or a short-circuit contact. Thereby, it is possible to prevent the output sections of the control means from short-circuiting even in a relay inoperable state when, for example, the control contact or the short-circuit contact of the relay has a welding failure or when the operation coil is disconnected. As a result, the risk of heat generation due to overcurrent can be reduced even in a relay inoperable state, and the safety and reliability of the electromagnetic suspension device can be improved.

  Moreover, in the relay inoperable state, it can be detected by the control means (for example, a sensor provided in the control means) that no current flows through the three-phase coil at the electrical angle as commanded by the control means. For this reason, it is not necessary to add a new sensor or logic for confirming the operation of the relay, and the cost can be reduced. In addition, the reliability of the control means and the linear electromagnetic actuator can be improved. In addition, it is possible to control the power lines for three phases and switch between short circuits with two relays. For example, compared to a configuration with three relays, the entire electromagnetic suspension device is reduced in size and the number of parts is reduced. This makes it possible to reduce costs, reduce failures, and improve reliability.

  On the other hand, the movable contact of each relay comes into contact with a control contact that becomes a fixed contact based on the magnetic force generated by the operation coil when the operation coil is energized, and a short circuit that becomes a fixed contact based on the spring force of the spring when not energized. Contact the contact. For this reason, when the operating coil is not energized, the three-phase power line is short-circuited (the three-phase coil is short-circuited), and the vehicle can be driven by the damping force (resistance force) generated by the power generated by the linear electromagnetic actuator. It can be. When the operation coil is energized, the three-phase coil and the control means are connected, and the control means controls the energization of the linear electromagnetic actuator, thereby performing control to improve the riding comfort and steering stability of the vehicle. be able to.

  Here, consider the case where the relay fails. For example, let us consider a case where a control contact is welded by a large current flowing between the control means (inverter) and the linear electromagnetic actuator (coil) when the operation coil is energized. In this case, energization is possible when performing control by the control means. On the other hand, when the operation coil is de-energized, the movable contact does not change from the control contact to the short-circuit contact, and therefore the phase in which the relay has failed cannot be short-circuited. However, in this case, the vehicle can travel with the damping force of two phases of the three phases. Thereby, safety and reliability can be ensured even when the relay fails (when the control contact is welded).

  Next, when a short-circuit contact is welded due to a large back electromotive force of the linear electromagnetic actuator (coil) when the operation coil is not energized, or when a short-circuit contact is maintained due to disconnection or failure of the relay operation coil Think about the case. In this case, when the control is not performed by the control means (inverter) and the control is OFF, it is possible to generate a damping force according to the back electromotive force of the linear electromagnetic actuator via the short-circuit contact. On the other hand, when the control is ON for performing the control by the control means, the movable contact does not change from the short-circuited contact to the control contact, so that conduction to the control contact becomes impossible. However, in this case, since it is possible to avoid a failure state in which the output unit of the control means is short-circuited, heat generation due to overcurrent can be suppressed. Thereby, safety and reliability can be ensured even when the relay fails (when the short-circuit contact is welded or when the short-circuit contact is maintained).

  According to the embodiment, the relay is configured to be built in the linear electromagnetic actuator. For this reason, even if the cable is disconnected between the control means and the linear electromagnetic actuator, the three-phase cable is short-circuited by de-energizing the relay operation coil built in the linear electromagnetic actuator. A damping force (resistance force) can be generated in the electromagnetic actuator. Thereby, also from this aspect, the safety and reliability of the electromagnetic suspension device can be improved.

  According to the embodiment, the capacity of the control contact is larger than the capacity of the short circuit contact. For this reason, the loss by the control contact at the time of control which flows a big electric current compared with the time of a short circuit reduces, and the risk that a control contact will fail can be reduced. Thereby, the safety | security and reliability of a relay can be improved. In addition, the capacity of the control contact and the short-circuit contact can be optimized, and the cost of the relay can be reduced.

  According to the embodiment, when the relay contacts are switched, the current flowing through the coils of each phase is set to zero amperes. For this reason, when switching the contact of the relay, it is possible to prevent a current from flowing through the relay and to minimize the load on the contact of the relay. Thereby, the lifetime improvement and reliability improvement of a relay can be aimed at.

1 Electromagnetic suspension device 2 Actuator (Linear electromagnetic actuator)
3 Inverter (control means)
3A, 3B, 3C Output 6A, 6B, 6C Power line (cable)
15 Coil member 15A, 15B, 15C Coil 16 Rod (inner cylinder)
22 Outer tube (outer cylinder)
26 Permanent magnet (magnetic member)
27, 28 Relay 29, 51 Control contact 30, 52 Short circuit contact 31 Movable contact 34 Fixed contact 37, 43 Spring 38, 44 Operation coil 40, 46 Magnetic body 61 Correction unit

Claims (4)

A linear electromagnetic actuator interposed between the vehicle body and the wheel;
Control means for controlling energization to the linear electromagnetic actuator,
The linear electromagnetic actuator is
A coil member which is provided on one member of a coaxial inner cylinder or outer cylinder which can be relatively displaced and constitutes a three-phase motor, and a magnetic member which is provided on the other member and faces the coil member;
When the coil member is energized, a propulsive force is obtained by an electromagnetic force generated between the coil member and when the coil member is de-energized, the coil member and the magnetic member are caused by relative displacement of the coil member. In an electromagnetic suspension device configured to be able to obtain a damping force by an electromotive force,
The control means and the coil of each phase of the coil member are connected by an independent cable,
Of the three-phase independent cables provided between the control means and the coil member, the two-phase cables are each provided with a relay,
Each relay has two contacts, a control contact and a short contact,
The control contact is a contact for connecting the two-phase coil and each output unit of the control means corresponding to the two-phase coil, and for supplying a current from the control means to the two-phase coil,
The short-circuit contact is a contact that connects one phase coil of the two-phase coil and another phase coil, and is connected to a cable not provided with the relay to flow current between the three-phase coils. ,
Each of the relays has a structure that can connect only either the control contact or the short-circuit contact,
And each said relay is
The control contact and the short-circuit contact, and the control contact and the short-circuit contact are provided separately from the fixed contact,
The relay is provided between the control contact and the short-circuit contact, and is brought into contact with the control contact by being guided to a magnetic body constituting the relay when energizing the operation coil constituting the relay, and the relay is constituted when not energized. An electromagnetic suspension device comprising: a movable contact that contacts the short-circuit contact by the spring force of the spring.   The electromagnetic suspension device according to claim 1, wherein the relay is built in the linear electromagnetic actuator.   The electromagnetic suspension device according to claim 1 or 2, wherein a capacity of the control contact is larger than a capacity of the short-circuit contact.   4. The electromagnetic suspension device according to claim 1, wherein when the contact of the relay is switched, the current flowing through the coil of each phase is set to zero ampere.

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