JP2006074884A - Torque motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a torque motor reduced in the length of a magnetic path from a coil part to a rotor, and thereby reduced in weight by the amount of the reduction of the length. <P>SOLUTION: The torque motor 10 comprises at least: the rotor 12 with a permanent magnet 12a formed at its periphery; a stator 14 arranged around the rotor; and a coil 20 that generates a rotating magnetic field to the stator when excited. When stator pieces formed by dividing the stator 14 into a plurality of pieces, more specifically, first and second halves 14a, 14b of the stator formed by dividing the stator into two pieces, are combined to the divided stator pieces (the halves 14a, 14b of the stator) to each other, the rotor 12 is arranged so as to penetrate the stator pieces and the coil 20 by comprising the coil 20 wound to a bobbin 16 that is formed into a shape so as to be freely accommodated between the halves of the stator. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a torque motor.

Conventionally, various types of torque motors have been proposed, and the technology described in Patent Document 1 is known as an example. The torque motor according to the proposed technology is a torque motor for a throttle device of an internal combustion engine, and has a substantially D-shaped stator core in plan view, a rotor formed with a permanent magnet on the outer periphery, and a rotor inserted into a curved portion of the stator core. A coil portion wound around the iron core of the straight portion on the opposite side to the curved portion, and the length of the conductor to be wound by making the cross section of the iron core of the coil portion into a shape with a part of a circle cut off Is configured to be shortened.
JP 2000-139067 A

  As described above, in the torque motor described in Patent Document 1, the rotor is disposed on the curved portion of the substantially D-shaped stator core in plan view, and the coil portion wound around the iron core of the linear portion on the opposite side. Since the magnetomotive force is generated, the distance (magnetic path) from the coil part, which is the source of the magnetomotive force, to the rotor becomes longer, in other words, the stator becomes larger and the weight increases accordingly. It was.

  Accordingly, an object of the present invention is to solve the above-described problems and to provide a torque motor that shortens the magnetic path from the coil portion to the rotor, and is thus made smaller and lighter.

  In order to solve the above-mentioned object, in claim 1, a rotor having a permanent magnet formed on the outer periphery, a stator arranged around the rotor, and a rotating magnetic field applied to the stator when excited. In a torque motor including at least a coil to be generated, a stator piece formed by dividing the stator into a plurality of pieces, and the coil configured to be accommodated between the divided stator pieces when combined. And the rotor is arranged so as to penetrate the plurality of stator pieces and the coil.

  In the torque motor according to claim 2, when the plurality of stator pieces are combined with the ring-shaped main body portion in plan view, the rotor portion moves toward the main body portion of the other stator piece from the main body portion. The two pieces are composed of two stator pieces each having a protruding portion that protrudes in a direction parallel to the axis, and the coils are formed in a circular shape that can be accommodated inside the main body, and are thus combined. The coil is configured to be concentric with the rotor when housed in the stator piece.

  The torque motor according to a third aspect is configured such that the projecting portion is projected locally in a direction parallel to the axis of the rotor from the circumference of the main body portion.

  In the torque motor according to a fourth aspect of the present invention, the coil is wound around a bobbin so as to be accommodated between the plurality of stator pieces.

  In the torque motor according to claim 5, the bobbin is configured to include a locking piece that restricts displacement of the stator pieces when the stator pieces are combined.

  In the torque motor according to claim 6, the coil is configured to include terminals with a winding start end and a winding end end formed in a shape connectable to an external device.

  In the torque motor according to claim 7, the terminal is configured to be freely drawn out through the inside of the engaging piece.

  In the torque motor according to claim 8, the rotor is attached to a shaft of a throttle valve mounted on an intake pipe of an internal combustion engine, and is configured to open and close the throttle valve by rotating the shaft.

  In the torque motor according to the first aspect, the stator includes a stator piece formed by dividing the stator into a plurality of pieces and a coil configured to be housed therebetween, and the rotor includes a plurality of stator pieces and the coil. Since the magnetic path covers the coil, the distance from the coil (magnetomotive force source) to the permanent magnet of the rotor can be shortened. Therefore, the stator can be made smaller and lighter, and the torque motor can be made smaller and lighter. Furthermore, since it is only necessary to insert the rotor while accommodating (sandwich) the coil with two stator pieces, the assembly is easy and the assembly cost can be reduced.

  In the torque motor according to claim 2, the plurality of stator pieces are projected in a direction parallel to the axis of the rotor toward the ring-shaped main body portion and then the main body portion of the other stator piece. When the coil is formed in a circular shape that can be housed inside the main body portion and is thus housed in the two stator pieces that are combined, the coil In addition to the effects described above, the magnetic path can surely cover the coil, the distance of the magnetic path can be shortened, and the stator can be made smaller and lighter. The torque motor can be made small and light.

  In the torque motor according to the third aspect, since the projecting portion is configured to project locally from the circumference of the main body portion in a direction parallel to the axis of the rotor, in addition to the above-described effect, the magnet motor can be more reliably configured. The path can cover the coil, the distance of the magnetic path can be shortened, the stator can be made smaller and lighter, and the torque motor can be made smaller and lighter.

  In the torque motor according to the fourth aspect, since the coil is wound around the bobbin and accommodated between the plurality of stator pieces, the coil is wound around the bobbin and accommodated between the stator pieces. This is sufficient, and in addition to the effects described above, assembly becomes easy.

  In the torque motor according to the fifth aspect, since the bobbin is configured to include a locking piece that restricts displacement of the stator pieces when the stator pieces are combined, the stator pieces are When combined, there is no inconvenience of displacement.

  In the torque motor according to the sixth aspect, since the coil is configured to include a terminal having a shape in which a winding start end and a winding end end can be connected to an external device, in addition to the above-described effects, Is easy to connect.

  In the torque motor according to the seventh aspect, since the terminal is configured so as to be freely drawn out through the inside of the locking piece, in addition to the above-described effect, the connection with the external device is further facilitated. Become.

  In the torque motor according to the eighth aspect, the rotor is attached to the shaft of the throttle valve attached to the intake pipe of the internal combustion engine, and is configured to open and close the throttle valve by rotating the shaft. It can be suitably used as an actuator near the throttle valve of a restricted internal combustion engine.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS The best embodiment of a torque motor according to the present invention will be described below with reference to the accompanying drawings.

  1 is a perspective view showing a torque motor according to a first embodiment of the present invention, FIG. 2 is an exploded perspective view of the torque motor shown in FIG. 1, and FIG. 3 is a sectional view of the torque motor shown in FIG.

  1 to 3, reference numeral 10 denotes a torque motor. The torque motor 10 includes a rotor 12, a stator (more specifically, a stator core) 14, and a coil 20 wound around a bobbin (coil bobbin) 16. Prepare. In FIG. 1 and the like, the thickness of the conductive wire of the coil 20 is exaggerated.

  The rotor 12 has a cylindrical shape, and a permanent magnet 12a composed of N poles and S poles is disposed (formed) on the outer periphery thereof. In the rotor 12, a rotor core 12b made of laminated steel plates is disposed inside the permanent magnet 12a, and a rotating shaft 12c is disposed inside (center) thereof. The permanent magnet 12a is made of, for example, a rare earth magnet such as neodymium or samarium / cobalt, or a ferrite magnet.

  The stator 14 is divided into a plurality of stator pieces. More specifically, as shown in the drawing, two stator pieces, that is, a first stator half (stator piece) 14a and a second stator half (stator piece). ) 14b. Each of the first and second stator half portions 14a and 14b includes a ring-shaped main body portion 14a1 and 14b1, and projecting portions 14a2 and 14b2 projecting therefrom.

  More specifically, when the first and second stator halves 14a and 14b are combined (when assembled), the protrusions 14a2 and 14b2 are connected to the main body 14b1 of the other stator half from the main body 14a1 and 14b1. , 14a1 so as to protrude from the main body portions 14a1 and 14b1 in a direction parallel to the axis (longitudinal direction) of the rotor 12.

  As shown in FIG. 3, when the ring-shaped first and second stator halves 14a and 14b are combined, the protrusions 14a2 and 14b2 are located outside the centers of the first and second stator halves 14a and 14b. A concentric cylinder 14c is formed, and a concentric hole 14d is formed inside the same similarly to the centers of the first and second stator halves 14a and 14b. The hole 14 d is formed in a circular shape corresponding to the rotor 12 and has an inner diameter larger than the diameter of the rotor 12.

  Since the first and second stator halves 14a and 14b each form a magnetic path, soft iron may be used. However, in order to increase the magnetic permeability, the powder magnetic core, that is, the ferrite powder particles having a high magnetic permeability, is insulated. It is desirable to mold by heating and compression together with a binder.

  The bobbin 16 is manufactured from an insulating material such as resin, and is formed in a circular shape as shown in the drawing in accordance with the shapes of the first and second stator halves 14a and 14b, and a circular hole 16a is formed at the center thereof. Drilled. A coil 20 made of a conductive wire is wound around the bobbin 16 (more precisely, the conductive wire is wound to form the coil 20). In addition, although illustration is abbreviate | omitted, resin is potted and the bobbin 16 is fixed after the coil 20 is wound.

  The bobbin 16 is accommodated between the first and second stator halves 14a and 14b by inserting the hole 16a into a cylinder 14c formed by two projecting portions 14a2 and 14b2. The rotor 12 having the permanent magnet 12a formed on the outer periphery is rotatably disposed in a hole 14d formed by the two protruding portions 14a2 and 14b2 so as to penetrate the two stator halves 14a and 14b and the bobbin 16. (Accommodated).

  Since the bobbin 16 is formed in a circular shape and is inserted into a column 14c concentric with the center of the first and second stator halves 14a and 14b having the same shape (ring shape), the combined first The coil 20 is concentric with the rotor 12 when housed inside the second stator halves 14a, 14b. In this state, the torque motor 10 is completed by being covered with the cover 22. The cover 22 is provided with a connector 24.

  Thus, the torque motor 10 according to this embodiment is configured as a 2-pole 2-stator motor. In this specification, the term “torque motor” means an electric motor mainly intended to generate torque in a limited operating range at the installed position. Specifically, the three-phase squirrel-cage induction motor It is a special case.

  1 and 2, when the first and second stator halves 14a and 14b are combined, the bobbin 16 regulates the displacement between the first and second stator halves 14a and 14b. A locking piece 16b is provided.

  In addition, the coil 20 wound around the bobbin 16 includes a terminal 20a having a winding start end and a winding end end formed in a shape connectable to an external device such as an energization circuit. The terminal 20a is configured to be able to be pulled out through the inside of the locking piece 16b.

  On the other hand, the connector 24 includes a pin 24 a, a lead 24 b connected to the pin 24 a and extending inside the cover 22, and a socket 24 c connected to the lead 24 b and formed on the back surface side of the cover 22. The socket 24c is formed at a position near the locking piece 16b when the bobbin 16 is accommodated in the first and second stator halves 14a and 14b.

  Therefore, when the bobbin 16 is accommodated in the first and second stator halves 14a and 14b, the terminal 20a is electrically connected to the socket 24c, the lead 24b, and the pin 24a. Thus, the terminal 20a is configured in such a shape that it can be directly connected to an external device such as an energizing circuit via the connector 24 arranged on the cover 22.

  That is, it is formed in a trapezoidal shape in a plan view as shown in the figure, and can be connected to an external device without using another connecting device by inserting it into a plug (not shown) having a corresponding shape on the external device side. Composed.

  In the torque motor 10 shown in FIG. 1, when the coil 20 is energized and energized from an AC power source (not shown) through the above-described energization path, the magnetic flux flows as schematically shown by arrows in FIG. A rotating magnetic field is formed in each of 14b and the rotor 12 is rotated. In the torque motor 10 according to this embodiment, the magnetic path covers (surrounds) the coil 20 as shown in FIGS. Configured.

  That is, in the torque motor 10 according to this embodiment, when the stator halves (stator pieces) 14a and 14b obtained by dividing the stator 14 into two parts and the divided stator halves 14a and 14b are combined, And the coil 20 wound around the bobbin 16 configured to be housed in the rotor, and the rotor 12 is disposed so as to penetrate the two stator halves 14a and 14b and the bobbin 16 (coil 20). Thus, the magnetic flux generated by the coil 20 flows as schematically shown by arrows in FIG.

  More specifically, the magnetic flux generated in the coil 20 flows as shown by arrows in FIGS. 5 and 6, and a magnetic path formed by the flow of the magnetic flux flows so as to cover (enclose) the coil 20.

  FIG. 7 shows the flow of magnetic flux (magnetic path) in the conventional torque motor described in Patent Document 1. As shown in FIG. 7A, the torque motor according to the prior art has a rotor 104 disposed on a curved portion 102 of a substantially D-shaped stator core 100 in a plan view, and is wound around an iron core on a linear portion on the opposite side. Since the magnetomotive force is generated by the coil portion 106, the distance (magnetic path) from the coil portion 106, which is the magnetomotive force generation source, to the rotor 104, indicated by arrows d1 and d2 in FIGS. The stator core 100 becomes larger and the weight increases by the length corresponding to the arrows d1 and d2.

  On the other hand, in the torque motor 10 according to this embodiment, since the magnetic path covers (encloses) the coil 20, the coil 20 (magnetomotive force generation source) 20 to the permanent magnet 12 a of the rotor 12. The distance (magnetic path) can be shortened by an amount substantially corresponding to the distance (magnetic path) indicated by arrows d1 and d2 in FIGS. 7A and 7B, and the stator 14 can be made smaller and lighter accordingly. Therefore, the torque motor 10 can be reduced in size and weight.

  Furthermore, since the rotor 12 can be inserted while the bobbin 16 is accommodated (sandwich) with the first and second stator halves 14a and 14b, the assembly is easy and the assembly cost is reduced. Can do.

  Further, since the bobbin 16 is provided with a locking piece 16b for restricting the displacement between the first and second stator halves 14a and 14b, the first and second stator halves 14a and 14b are combined. Sometimes, there is no inconvenience of displacement.

  In addition, the coil 20 includes a terminal 20a having a shape at which a winding start end and a winding end end can be connected to an external device such as an energization circuit, and the terminal 20a can be pulled out to the outside through the locking piece 16b. Therefore, connection with an external device becomes easier.

  FIG. 8 is an explanatory sectional view showing a case where the torque motor 10 according to this embodiment is applied to a throttle device for an internal combustion engine.

  In the following description, reference numeral 30 denotes an intake pipe of an internal combustion engine. A throttle valve 32 is attached to the intake pipe 30 so as to open and close the intake passage, and the torque motor 10 shown in FIG. The cover 220 is covered and attached. That is, the throttle valve 32 is a DBW (Drive By Wire) mechanically separated from an accelerator pedal (not shown) disposed on the vehicle driver's seat floor.

  The throttle valve 32 includes a shaft 32 a that is rotatably attached to the intake pipe 30 via a bearing 34. The shaft 32a is press-fitted into the rotor 12 of the torque motor 10 to constitute the rotary shaft 12c described above, rotates together with the rotor 12, and drives the throttle valve 32 to open and close the intake passage.

  The shaft 32a is connected to the return spring 36 on the other end side, and is urged in the direction in which the throttle valve 32 is closed. In the vicinity of the position where the return spring 36 is disposed, an angle sensor (throttle opening sensor) 40 comprising a rotary encoder is disposed in the case 42, and the position of the throttle valve 32, that is, the throttle opening is determined through the rotation amount of the shaft 32a. Output the signal.

  The output of the angle sensor 40 is sent to an electronic control unit comprising a microcomputer (not shown), where the throttle opening is detected. The electronic control unit determines the throttle opening based on the output of the angle sensor 40 and other sensor outputs (not shown), and energizes the coil 20 of the torque motor 10 via a drive circuit (not shown). Although not shown, the drive circuit is connected to the terminal 20a of the coil 20 via the connector 240 (having a shape similar to the connector 24).

  Thus, since the torque motor 10 according to this embodiment is small and light, it can be suitably used as an actuator near the throttle valve of an internal combustion engine in which space is restricted.

  FIG. 9 is a perspective view similar to FIG. 1, showing a torque motor according to the second embodiment of the present invention.

  A description will be given focusing on the differences from the first embodiment. In the torque motor 10 according to the second embodiment, the bobbin 16 is removed, and the first and second stator halves 14a and 14b are separated. Further, the coil 20 is accommodated as it is in a wound state.

  Specifically, a self-bonding wire, that is, a so-called cemented enameled wire provided with a self-adhesive layer on the surface of various synthetic enameled wires is used as the conductive wire of the coil 20, and the conductive wire (self-bonding) is provided around an appropriate die. After the wire was wound, it was extracted from the die, and then heated so that the self-adhesive layer of the adjacent conductor was melted and bonded together. The remaining configuration is not different from the first embodiment.

  Since the torque motor 10 according to the second embodiment is configured as described above, compared to the first embodiment, the torque motor 10 has an effect that the configuration is simplified by the amount that the bobbin is unnecessary. The remaining effects are the same as in the first embodiment.

  As described above, in the first and second embodiments, the rotor 12 having the permanent magnet 12a formed on the outer periphery, the stator 14 arranged around the rotor, and the stator rotate when excited. In the torque motor 10 including at least a coil 20 for generating a magnetic field, a stator piece obtained by dividing the stator 14 into a plurality of pieces, more specifically, first and second stator half parts divided into two pieces. When the divided stator pieces (stator half portions 14a and 14b) are combined, the coil 20 is configured so as to be housed therebetween, and the rotor 12 includes the plurality of rotor pieces. The stator piece (the stator half portions 14a and 14b) and the coil 20 are arranged so as to pass through.

  When the plurality of stator pieces are combined with ring-shaped main body portions 14a1 and 14b1 in plan view, the main body portion is directed in a direction parallel to the axis of the rotor 12 toward the main body portion of the other stator piece. It is composed of two stator pieces (stator half portions 14a and 14b) made of projecting portions 14a2 and 14b2, and the coil 20 is formed in a circular shape that can be accommodated inside the main body portion. The coil is configured to be concentric with the rotor when housed in the two stator pieces.

  The projecting portions 14a2 and 14b2 are configured to project locally from the circumference of the main body portion in a direction parallel to the axis of the rotor 12.

  Further, the coil 20 is configured to be wound around the bobbin 16 and accommodated between the plurality of stator pieces.

  The bobbin 16 is configured to include a locking piece 16b that restricts displacement of the stator pieces when the stator pieces are combined.

  In addition, the coil 20 is configured to include a terminal 20a formed so that a winding start end and a winding end end can be connected to an external device.

  Further, the terminal 20a is configured so as to be freely drawn out through the inside of the engaging piece 16b.

  The rotor 12 is attached to a shaft 32a of a throttle valve 32 mounted on the intake pipe 30 of the internal combustion engine, and thus the throttle valve is opened and closed by rotating the shaft.

  In the above description, the torque motor 10 is configured as a 2-pole 2-stator. However, as shown in FIG. 10, the stator 14 having the same structure is laminated in the axial direction of the rotor 12 by shifting the phase by 90 degrees. It can also be a stator. Further, a two-pole six-stator can be formed by laminating a stator having the same structure on the top thereof with a phase shifted by 120 degrees (in this case, a three-phase motor is obtained).

  Thus, in the torque motor 10 according to the first and second embodiments, a large number of stators 14 can be stacked while shifting the phase.

  Further, in the above, the stator 14 is divided into two stator pieces (stator half portions). However, when combined, the stator 14 can be divided into three or more stator pieces as long as the coil can be accommodated therebetween. is there.

  Further, in the above, the torque motor 10 is not limited to the illustrated configuration. For example, in the first embodiment, the rotor core 12b is composed of laminated steel plates, but is not limited thereto, and may be composed of any material as long as it is a magnetic material.

  In the second embodiment, the self-bonding wire is used as the material of the coil 20, but a normal conductive wire may be used and molded into the same shape with resin or the like.

  Moreover, although the case where the torque motor 10 was applied to the throttle device of an engine was shown, the application destination of the torque motor 10 according to the present invention is not limited thereto.

1 is a perspective view showing a torque motor according to a first embodiment of the present invention. FIG. 2 is an exploded perspective view of the torque motor shown in FIG. 1. It is sectional drawing of the torque motor shown in FIG. It is a perspective view of the stator which shows typically the flow of the magnetic flux of the torque motor shown in FIG. It is a fragmentary sectional view of the stator half part which shows typically the flow of magnetic flux of the torque motor shown in FIG. Similarly, it is a fragmentary sectional view of a stator half part schematically showing the flow of magnetic flux of the torque motor shown in FIG. It is explanatory drawing which shows typically the flow of the magnetic flux of the torque motor which concerns on a prior art. FIG. 2 is an explanatory sectional view showing a case where the torque motor 10 shown in FIG. 1 is applied to a throttle device for an internal combustion engine. It is the perspective view similar to FIG. 1 which shows the torque motor which concerns on 2nd Example of this invention. It is the perspective view similar to FIG. 1 which shows the modification of the torque motor which concerns on 1st and 2nd Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Torque motor 12 Rotor 12a Permanent magnet 12b Rotor core 12c Rotating shaft 14 Stator 14a, 14b 1st, 2nd stator half part (stator piece)
14a1, 14b1 Body 14a2, 14b2 Projection 14c Column 14d Hole 16 Bobbin 16a Hole 16b Locking piece 20 Coil 20a Terminal 30 Intake pipe 32 Throttle valve 32a Shaft

Claims (8)

  In a torque motor comprising at least a rotor having a permanent magnet formed on the outer periphery, a stator disposed around the rotor, and a coil that generates a rotating magnetic field when excited, the stator includes a plurality of stators. When the divided stator pieces and the divided stator pieces are combined, the coil is configured so as to be housed therebetween, and the rotor includes the plurality of stator pieces and the coils. A torque motor arranged so as to penetrate therethrough.   When the plurality of stator pieces are combined with a ring-shaped main body portion in plan view, a protrusion portion that protrudes from the main body portion toward the main body portion of the other stator piece in a direction parallel to the axis of the rotor; When the coil is formed in a circular shape that can be accommodated inside the main body portion, and is thus accommodated in the combined two stator pieces, The torque motor according to claim 1, wherein the coil is concentric with the rotor.   The torque motor according to claim 2, wherein the protruding portion is protruded locally from the circumference of the main body portion in a direction parallel to the axis of the rotor.   4. The torque motor according to claim 1, wherein the coil is wound around a bobbin and accommodated between the plurality of stator pieces. 5.   The torque motor according to claim 4, wherein the bobbin includes a locking piece that restricts displacement of the stator pieces when the stator pieces are combined.   The torque motor according to any one of claims 1 to 5, wherein the coil includes a terminal having a winding start end and a winding end end formed in a shape connectable to an external device.   The torque motor according to claim 5 or 6, wherein the terminal is configured to be freely drawn out through the inside of the engaging piece.   8. The rotor according to claim 1, wherein the rotor is attached to a shaft of a throttle valve mounted on an intake pipe of an internal combustion engine, and the throttle valve is opened and closed by rotating the shaft. The described torque motor.

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