JP2009001246A - Electric power steering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce assembling man-hours and to improve layout property, in an electric power steering device provided with an electric motor and a control unit. <P>SOLUTION: In the electric power steering device 10 provided with a gear box 30, the electric motor 20 and ECU 40, a flange 26 having a bolt insertion hole 27 is provided on the electric motor 20, and a stay 42 having an oblong hole 43 and extended in a mounting direction to the electric motor 20 is provided on the ECU 40. The oblong hole 43 of the stay 42 is superposed on the bolt insertion hole 27 of the flange 26, a fastening bolt 50 is penetrated through the bolt insertion hole 27 and the oblong hole 43, and the fastening bolt 50 is threadedly engaged with a screw hole 31 of the gear box 30. The electric motor 20 and the ECU 40 are thereby fixed to the gear box 30. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electric power steering apparatus, and more particularly, to an electric power steering apparatus in which an electric motor and a control unit are disposed in close proximity.

In an electric power steering system, the electric motor and ECU (control unit) are placed close together to improve layout (aesthetics in the arrangement of each component), improve output, realize heat countermeasures, and achieve electromagnetic compatibility. It is effective to arrange them. For this reason, in recent years, a structure in which the ECU is mounted on an electric motor has been proposed (see, for example, Patent Document 1).
JP 2002-127721 A

  However, in the conventional electric power steering apparatus as described in Patent Document 1, it is necessary to assemble the assembly to the gear box after the ECU is mounted on the electric motor to form the assembly (assembly). The assembly man-hours were increasing. In addition, when a conventional electric power steering device is employed, it is necessary to route and connect a wire harness composed of various signal wires between the ECU and the electric motor after the ECU is mounted on the electric motor. Depending on the case, the layout may be deteriorated.

  The present invention has been made in view of such circumstances, and an object of the present invention is to reduce the number of assembling steps and improve the layout in an electric power steering apparatus including an electric motor and a control unit.

  In order to achieve the above object, an electric power steering apparatus according to the present invention is an electric power steering apparatus including a gear box, an electric motor, and a control unit, and the electric motor and the control unit are jointly fastened with a common bolt. Is attached to the gear box.

  If such a configuration is adopted, the electric motor and the control unit are attached to the gear box by using a common bolt, so that the number of assembly bolts can be reduced by reducing the number of fastening bolts. The electric motor can be assembled in close proximity. Accordingly, it is possible to improve layout while obtaining good assembly workability.

  In the electric power steering apparatus, an electric motor having a flange provided with a motor side insertion hole through which a bolt is inserted is adopted, and a unit side insertion hole through which the bolt is inserted is provided and extends in a mounting direction to the electric motor. A control unit having a tongue piece can be employed. In such a case, the unit side insertion hole of the tongue piece is overlapped with the motor side insertion hole of the flange, the bolt is inserted into the motor side insertion hole and the unit side insertion hole, and the bolt is screwed into the screw hole of the gear box, An electric motor and a control unit can be fixed to the gear box.

  In the electric power steering apparatus, an electric motor having a motor-side connector and a control unit having a unit-side connector connected to the motor-side connector can be adopted. In such a case, with the unit side connector connected to the motor side connector, a bolt can be inserted into the motor side insertion hole and the unit side insertion hole, and the electric motor and the control unit can be fixed to the gear box.

  By adopting such a configuration, the electric motor and the control unit can be fixed to the gear box, and at the same time, the motor side connector and the unit side connector can be connected to electrically connect the electric motor and the control unit. Thereby, exposure of a wire harness can be eliminated compared with the case where an electric motor and a control unit are electrically connected by a wire harness. Therefore, it is possible to improve the layout, and to improve the resistance to the stepping stone in the case of the rack assist type or pinion assist type electric power steering device. Further, by adopting a harnessless structure, it is possible to realize improvement in output and compatibility with electromagnetic properties.

  Further, in the electric power steering apparatus, the motor side connector and the unit side connector each store power system connection terminals for transferring power between the electric motor and the control unit, and the motor side connector includes the unit side connector. It can be configured that the power system connection terminals are connected to each other when they are connected.

  When such a configuration is adopted, the electric motor and the control unit can be fixed to the gear box, and at the same time, the power system connection terminals housed in the connectors of the electric motor and the control unit can be connected. Therefore, a power system wire harness can be eliminated.

  In the electric power steering apparatus, the motor side connector and the unit side connector each store a signal system connection terminal for transmitting and receiving signals between the electric motor and the control unit, and the motor side connector has a unit side connector. The signal system connection terminals can be connected to each other when they are connected.

  By adopting such a configuration, it is possible to connect the signal system connection terminals of the connectors of the electric motor and the control unit together with fixing the electric motor and the control unit to the gear box. Therefore, a signal transmission / reception system wire harness can be eliminated.

  Further, in the electric power steering apparatus, a power system connection terminal and a signal system connection terminal for transferring power and transmitting / receiving signals between the electric motor and the control unit are respectively stored in the motor side connector and the unit side connector. Then, when the unit side connector is connected to the motor side connector, the power system connection terminals and the signal system connection terminals can be connected to each other.

  When this configuration is adopted, the electric motor and the control unit can be fixed to the gear box, and at the same time, the power system connection terminals and the signal system connection terminals of the connectors of the electric motor and the control unit can be connected. Therefore, the power system and signal transmission / reception system wire harnesses can be eliminated.

  In the electric power steering device, a positioning groove is formed in the flange of the electric motor along the mounting direction to the control unit, and the tongue of the control unit is fitted into the groove of the electric motor, thereby controlling the electric motor. The unit can be positioned with respect to the electric motor.

  By adopting such a configuration, the control unit can be positioned with respect to the electric motor very easily by fitting the tongue portion of the control unit into the groove of the electric motor. Therefore, the assembly workability can be further improved.

  In the electric power steering apparatus, the relative position of the motor side connector with respect to the electric motor and / or the relative position of the unit side connector with respect to the control unit may be changed.

  When such a configuration is adopted, since at least one of the connectors on the electric motor side and the controller unit side can be displaced, a slight displacement of the connectors of the electric motor and the controller unit can be allowed. Therefore, it is possible to connect the connectors well and smoothly.

  In the electric power steering apparatus, a long hole extending in the direction of attachment to the electric motor can be adopted as the unit side insertion hole of the control unit.

  When such a configuration is adopted, a slight positional shift of the unit side insertion hole with respect to the motor side insertion hole can be allowed. Therefore, it is possible to securely insert the bolts into these insertion holes and fasten them together.

  According to the present invention, in an electric power steering apparatus including an electric motor and a control unit, it is possible to reduce assembly man-hours and improve layout.

  Hereinafter, an electric power steering apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  First, the configuration of the electric power steering apparatus 1 according to the present embodiment will be described with reference to FIGS.

  As shown in FIG. 1, the electric power steering apparatus 10 includes an electric motor 20 and a gear box 30, and the electric motor 20 is assembled to the gear box 30. The gear box 30 houses a reduction gear (not shown) that decelerates the rotation of the electric motor 20 and transmits it to a steering shaft rotatably supported in the steering column. Further, as shown in FIG. 2, the electric motor 20 is assembled with an ECU (control unit) 40 that houses a controller that controls the rotation of the electric motor 20 based on signals such as a vehicle speed signal and a torque signal. ing.

  As shown in FIG. 3, the electric motor 20 has a motor body 23 that houses a stator 21 and a rotor 22, and a rotating shaft 24 provided at the center of the rotor 22 is rotatably supported by a bearing 25. ing. A flange 26 is formed on the motor main body 23 on the attachment side to the gear box 30, and the rotary shaft 24 projects from the flange 26 toward the gear box 30.

  A bolt insertion hole 27 is formed in the flange 26 of the electric motor 20. The bolt insertion hole 27 communicates with a screw hole 31 formed on the attachment side of the gear box 30 with the electric motor 20. A fastening bolt 50 that is inserted into a long hole 43 of a stay 42 (to be described later) of the ECU 40 is inserted into the bolt insertion hole 27, and the fastening bolt 50 is screwed into the screw hole 31 of the gear box 30. Yes. The bolt insertion hole 27 of the electric motor 20 corresponds to the motor side insertion hole in the present invention.

  In addition, positioning flanges 28 are formed on the flange 26 of the electric motor 20 on the surface side opposite to the gear box 30, and stays 42 of the ECU 40 are positioned and fitted in these grooves 28. The electric motor 20 is provided with a motor-side connector 29 on the ECU 40 side, and the motor-side connector 29 is connected to a unit-side connector 44 provided on the ECU 40.

  The ECU 40 includes a box-shaped case main body 41, and a controller is accommodated in the case main body 41. The case main body 41 is provided with a pair of stays (tongue piece portions) 42 at the lower ends thereof so as to extend toward the electric motor 20, and these stays 42 are placed in the grooves 28 of the flange 26 of the electric motor 20. It is inserted. The stay 42 is formed with elongated holes 43 extending along the direction of attachment to the electric motor 20, and the fastening bolts 50 are inserted through these elongated holes 43. The long hole 43 corresponds to the unit side insertion hole in the present invention.

  Further, the case main body 41 of the ECU 40 is provided with a unit side connector 44 on the electric motor 20 side at the lower end, and the unit side connector 44 is connected to the motor side connector 29 of the electric motor 20. The unit-side connector 44 is configured so that the relative position with respect to the case main body 41 can be changed by a rubber mount or the like.

  The motor side connector 29 and the unit side connector 44 accommodate a power system connection terminal and a signal system connection terminal, respectively. Therefore, by connecting the motor-side connector 29 and the unit-side connector 44, the power system connection terminals and the signal system connection terminals are connected to each other, the supply of power from the ECU 40 to the electric motor 20, and the electric motor 20 Both transmission and reception of position detection signals and control signals between the ECU 40 and the ECU 40 are possible.

  Next, an assembly method of the electric power steering apparatus 10 according to the present embodiment will be described with reference to FIGS.

  As shown in FIG. 4, the electric power steering device 10 assembles the electric motor 20 in the gear box 30 in the direction of the arrow A, and makes the ECU 40 approach the electric motor 20 in the direction of the arrow B and arranges it at a predetermined position. Thereafter, the fastening bolt 50 is screwed in the direction of the arrow C, and the electric motor 20 and the ECU 40 are fastened and fixed to the gear box 30 for assembly.

  Specifically, first, as shown in FIG. 4, the electric motor 20 is assembled to the gear box 30 while the rotating shaft 24 of the electric motor 20 is inserted into the gear box 30, and in this state, FIGS. As shown in B), the ECU 40 is approached from the side of the electric motor 20, and the stay 42 of the ECU 40 is fitted into the groove portion 28 of the flange 26 of the electric motor 20. Thus, the stay 42 is fitted along the groove 28, whereby the ECU 40 is positioned with respect to the electric motor 20, whereby the motor-side connector 29 of the electric motor 20 faces the unit-side connector 44 of the ECU 40.

  Further, when the ECU 40 is brought close to the electric motor 20 with the stay 42 of the ECU 40 fitted along the groove 28 of the electric motor 20, a part of the long hole 43 of the ECU 40 overlaps with the bolt insertion hole 27 of the electric motor 20. In the present embodiment, when the bolt insertion hole 27 and a part of the long hole 43 overlap in this way, the fastening bolt 50 is inserted into the holes 43 and 27 as shown in FIG. The electric motor 20 and the ECU 40 are temporarily fixed to the gear box 30 by being shallowly screwed into the screw holes 31 of the gear box 30. Even during the temporary fixing, the stay 42 of the ECU 40 is fitted into the groove 28 of the electric motor 20, so that the rotation of the ECU 40 relative to the electric motor 20 is prevented. That is, the groove portion 28 of the electric motor 20 also functions as a detent.

  When the electric motor 20 and the ECU 40 are temporarily fixed to the gear box 30 as described above and the ECU 40 is further brought closer to the electric motor 20, the unit-side connector 44 of the ECU 40 is connected to the motor-side connector 29 of the electric motor 20. The At this time, the unit-side connector 44 of the ECU 40 is configured to be displaceable with respect to the case main body 41, so that even if the position of the ECU 40 with respect to the electric motor 20 is slightly shifted, it is securely connected to the motor-side connector 29. The Then, by connecting the motor side connector 29 and the unit side connector 44, the power system connection terminals and the signal system connection terminals are connected to each other, the supply of power from the ECU 40 to the electric motor 20, and the electric motor Both transmission and reception of position detection signals and control signals between the ECU 20 and the ECU 40 are possible.

  After the motor-side connector 29 of the electric motor 20 and the unit-side connector 44 of the ECU 40 are completely connected, the fastening bolt 50 is deeply screwed into the screw hole 31 of the gear box 30 to perform the final fastening. In this way, the stay 42 of the ECU 40 and the flange 26 of the electric motor 20 are fastened together and fixed to the gear box 30 by the fastening bolt 50, and the gear box 30, the electric motor 20, and the ECU 40 are integrated.

  In the electric power steering apparatus 10 according to the embodiment described above, the electric motor 20 and the ECU (control unit) 40 are fastened together and fixed to the gear box 30 with a common fastening bolt 50. The number of assembly steps can be reduced by reducing the number of bolts, and the ECU 40 can be disposed close to the electric motor 20. Accordingly, it is possible to improve layout while obtaining good assembly workability.

  Further, in the electric power steering apparatus 10 according to the embodiment described above, the electric motor 20 and the ECU 40 are fixed to the gear box 30, and at the same time, the motor side connector 29 and the unit side connector 44 are connected to each connector 29, The power system connection terminals and the signal system connection terminals housed in 44 can be connected. Therefore, the power system and signal transmission / reception system wire harnesses can be eliminated. Thereby, since exposure of a wire harness can be eliminated compared with the case where the electric motor 20 and ECU40 are electrically connected by a wire harness, the improvement of layout property and the tolerance with respect to a flying stone can be aimed at. Further, by adopting a harnessless structure, it is possible to realize improvement in output and compatibility with electromagnetic properties. Furthermore, since the stay 42 of the ECU 40 and the flange 26 of the electric motor 20 are in contact with each other over a wide area, a high heat dissipation effect can be expected.

  In the electric power steering apparatus 10 according to the embodiment described above, a positioning groove 28 is formed in the flange 26 of the electric motor 20 along the mounting direction to the ECU 40, and the stay 42 of the ECU 40 is connected to the electric motor 20. The ECU 40 can be positioned with respect to the electric motor 20 very easily by being fitted into the groove portion 28. Therefore, the assembly workability can be further improved.

  Further, in the electric power steering apparatus 10 according to the embodiment described above, since the unit side connector 44 can be displaced with respect to the ECU 40, a slight positional deviation of the unit side connector 44 with respect to the motor side connector 29 is allowed. Can do. Therefore, it is possible to connect the connectors well and smoothly.

  Further, in the electric power steering apparatus 10 according to the embodiment described above, the long hole 43 extending in the mounting direction to the electric motor 20 is adopted as the unit side insertion hole of the ECU 40. A slight positional deviation with respect to the bolt insertion hole 27 can be allowed. Therefore, the fastening bolt 50 can be reliably inserted into both the holes 43 and 27 and fastened together.

  In the above embodiment, an example in which the long and narrow rectangular stay 42 is employed as the tongue piece portion and the groove portion 28 having a shape corresponding to the stay 42 is employed. The shape and size of the tongue piece and the groove are not limited to this.

  Moreover, although the example which accommodated both the power terminal and the signal terminal in the connectors 29 and 44 was shown in the above embodiment, these power terminals and a signal terminal can also be accommodated in a separate connector.

  Moreover, in the above embodiment, although the structure which changes the relative position of the unit side connector 44 with respect to ECU40 was employ | adopted, the structure which changes the relative position of the motor side connector 29 with respect to the electric motor 20 is employ | adopted. You can also. Further, both the motor-side connector 29 and the unit-side connector 44 may be configured to be displaceable with respect to the electric motor 20 and the ECU 40, respectively.

  In particular, when applied to a pinion assist type installed near the axle, the connectors 29 and 44 of the ECU 40 and the electric motor 20 are rubber-mounted for the purpose of providing a large clearance due to dimensional tolerances and the purpose of providing a waterproof structure. It is desirable to be able to displace by. And even in the pinion assist type, which requires a countermeasure for stepping stones compared to the rack assist type, the mechanical strength is improved by connecting the power system and the signal system with the connectors 29 and 44 as in this embodiment. The exposure of a relatively weak wire harness can be eliminated, and a sufficient stepping stone can be taken.

1 is a side view of an electric power steering apparatus according to an embodiment of the present invention. FIG. 2 is a plan view of the electric power steering device shown in FIG. 1. It is sectional drawing for demonstrating the structure of the electric motor mounted in the electric power steering apparatus shown in FIG. It is a disassembled side view for demonstrating the assembly method of the electric power steering apparatus shown in FIG. It is for demonstrating the procedure which attaches ECU to the electric motor of the electric power steering apparatus shown in FIG. 1, (A) is a side view, (B) is a top view. It is a side view for demonstrating the procedure which fixes the electric motor and ECU of the electric power steering apparatus shown in FIG. 1 to a gear box.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Electric power steering apparatus, 20 ... Electric motor, 26 ... Flange, 27 ... Bolt insertion hole (motor side insertion hole), 28 ... Groove part, 29 ... Motor side connector, 30 ... Gear box, 31 ... Screw hole, 40 ... ECU (control unit), 42 ... stay (tongue piece), 43 ... long hole (unit side insertion hole), 44 ... unit side connector, 50 ... fastening bolt.

Claims (9)

An electric power steering device comprising a gear box, an electric motor, and a control unit,
The electric motor and the control unit are attached to the gear box by being fastened together with a common bolt.
Electric power steering device. The electric motor has a flange provided with a motor side insertion hole through which the bolt is inserted,
The control unit is provided with a unit-side insertion hole through which the bolt is inserted, and has a tongue piece extending in the mounting direction to the electric motor,
The unit side insertion hole of the tongue piece is overlapped with the motor side insertion hole of the flange, the bolt is inserted into the motor side insertion hole and the unit side insertion hole, and the bolt is used as a screw hole of the gear box. By screwing, the electric motor and the control unit are fixed to the gear box.
The electric power steering apparatus according to claim 1. The electric motor has a motor-side connector,
The control unit has a unit side connector connected to the motor side connector,
With the unit side connector connected to the motor side connector, the bolt is inserted into the motor side insertion hole and the unit side insertion hole, and the electric motor and the control unit are fixed to the gear box,
The electric power steering apparatus according to claim 2. The motor-side connector and the unit-side connector each have a power system connection terminal for transferring power between the electric motor and the control unit,
When the unit side connector is connected to the motor side connector, the power system connection terminals are connected to each other.
The electric power steering apparatus according to claim 3. The motor-side connector and the unit-side connector each have a signal system connection terminal for transmitting and receiving signals between the electric motor and the control unit,
When the unit side connector is connected to the motor side connector, the signal system connection terminals are connected to each other.
The electric power steering apparatus according to claim 3. The motor-side connector and the unit-side connector each have a power system connection terminal and a signal system connection terminal for transmitting and receiving power and transmitting and receiving signals between the electric motor and the control unit.
When the unit side connector is connected to the motor side connector, the power system connection terminals and the signal system connection terminals are connected to each other,
The electric power steering apparatus according to claim 3. The flange of the electric motor has a positioning groove formed along the mounting direction to the control unit,
The control unit is positioned with respect to the electric motor by fitting the tongue piece of the control unit into the groove of the electric motor.
The electric power steering device according to any one of claims 2 to 6. The relative position of the motor-side connector with respect to the electric motor and / or the relative position of the unit-side connector with respect to the control unit are configured to be changeable.
The electric power steering device according to any one of claims 3 to 7. The unit side insertion hole of the control unit is a long hole extending in the mounting direction to the electric motor.
The electric power steering apparatus according to any one of claims 2 to 8.

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