JP2000078798A - Motor and electric power steering apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To install a control driving section and an apparatus body integrally without damaging workability on assembly in a motor, in which a power supply section is arranged to a yoke interior section with one end closed. SOLUTION: In the motor 90 with a cylindrical yoke 110, in which one-end side end section has a sidewall 109, a driver unit 91 for controlling and driving the motor 90 is housed at an end section on the sidewall 109 in the yoke 110. A feed opening section 103 communicating the inside and the outside of the yoke 110 and a signal-conductor opening section 104 are formed to the sidewall 109, and the driver unit 91 is connected electrically through these opening sections. The driver unit 91 is disposed into the yoke 110 under the state in which FETs 95 for the driver unit 91 are brought into contact directly with the sidewall 109.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric motor (motor) provided with a control driving means, and more particularly to a technique effective when applied to an electric power steering device for a vehicle.

[0002]

2. Description of the Related Art In recent years, many vehicles are equipped with a so-called power steering device for assisting the steering force of the vehicle, and various power steering devices such as a hydraulic type and an electric type have been proposed. Among such power steering devices, an electric power steering device (so-called electric power steering) applied to a rack and pinion type steering device includes:
There is known a rack assist type in which a steering assist force is obtained by an electric motor provided coaxially with a rack shaft. Here, an electric motor in which a field device, an armature, and the like are incorporated in a cylindrical yoke is used, and the steering force is assisted by the electric motor.

FIG. 6 is an explanatory diagram showing an example of a rack assist type power steering device using such an electric motor.
As shown in FIG. 6, the electric power steering device includes an electric motor 52 provided coaxially with a rack shaft 51, and transmits a steering assist force generated by the electric motor 52 to the rack shaft 51 via a ball screw mechanism 53. . Then, the steered wheels are steered by the steering assist force and the manual steering force, so that the driver's steering burden is reduced.

In this case, the rack shaft 51 is connected at both ends to steered wheels via tie rods or knuckle arms and the like, and is connected to a steering shaft 54 connected to a steering handle or the like by rack and pinion. The driver reciprocates in the left-right direction in FIG. 6 by the steering operation of the driver. The electric motor 52 has a configuration in which a cylindrical armature shaft 56 and a field device 57 are coaxially inserted into a cylindrical yoke 55, and power is supplied from a power supply unit 58. Further, the field device 57 includes a magnet 59 attached to the inner periphery of the yoke 55 and an armature core 60 attached to the outer periphery of the armature shaft 56. The rotational force generated by the electric motor 52 is transmitted as a reciprocating motion in the axial direction to the rack shaft 51 via a ball screw mechanism 53 provided at the left end of the armature shaft 56 in the drawing, thereby assisting the steering force.

[0005] The power supply section 58 is provided with a brush 61 and a commutator 62 slidably contacting the brush 61, through which electric power is supplied to the armature portion of the electric motor 52. In this case, the brush 61 is housed and held in a brush holder 63, and is provided with a commutator 6 by a not-shown elastic machine.
2 is pressed with a predetermined pressing force. Also, brush 6
A terminal plate 65 is spot-welded to one end of one pigtail 64. The terminal plate 65 is connected to the housing 6.
6 and project outside to the outside, where a coupler 67 is attached to form a power supply terminal.

[0006] On the other hand, there has been proposed a power steering device and a control drive unit thereof which are integrated with a control element such as an FET in such a power supply unit. For example, JP-A-6-2
No. 55504 discloses an electric power system in which a hollow chamber is formed at a joint between a housing accommodating a brushless motor and a housing accommodating a handle shaft, and a power circuit unit accommodating an FET and a circuit board is disposed therein. A steering device is shown. Also, JP-A-8-26125
Japanese Patent Application Laid-Open Publication No. H11-163873 discloses an electric steering device in which a FET and a substrate are accommodated in a gear box housing that holds a steering shaft and is connected to a motor yoke.

[0007]

Here, in the motor used in the apparatus shown in FIG.
The power supply unit is configured to be provided on the opening end side of the yoke or on the joint between the motor side housing and the steering shaft side housing. For this reason, since a brush, a control circuit, and the like can be incorporated near the opening end of the yoke and near the dividing surface, the apparatus main body and the control drive unit can be easily integrated, and there is no problem in assembling work.

However, in a motor using a cylindrical yoke having a side wall on one end side and a power supply section provided on the side wall side, the power supply section does not come to the opening. In addition, the control drive cannot be easily integrated. In other words, if the control drive unit is to be integrated into such a motor, various components must be incorporated into the back of the yoke from the opening side, causing a problem in terms of assembly workability.

In a power steering apparatus, a housing and a yoke on a steering shaft side are integrally formed, and a power supply unit, an armature, a field device, and the like are incorporated therein, and this is used as another component housing a ball screw mechanism. In the case of the type coupled to the housing, the power supply section is not provided near the divided portion. That is, in this type of power steering device, one end of the steering shaft side housing is formed in a closed cylindrical shape except for the rack shaft insertion portion, and the power supply portion is disposed at the innermost portion of the closed end. Therefore, even in such a power steering device, if the control drive unit is to be integrated, it is necessary to incorporate various components from the opening side to the back of the housing, which is difficult in terms of assembly workability. For this reason, a configuration in which a space for a control section is provided in a part of the housing and a control element and a substrate are incorporated therein cannot be easily adopted as in the above example, and improvement thereof has been desired.

[0010] It is an object of the present invention to provide a motor of this type in which a control drive unit is provided integrally with the apparatus main body without impairing the assembling workability. Another object of the present invention is to provide a control drive unit of an electric power steering device integrally with the device main body without impairing assembly workability.

[0011]

SUMMARY OF THE INVENTION An electric motor according to the present invention is a motor having a cylindrical yoke having a side wall at one end, and the motor is controlled and driven at an end on the side wall inside the yoke. And a control driving means for the control. Thus, even in the case of an electric motor in which the power supply unit is arranged at the back of the yoke, it is possible to integrally provide the control drive means with the electric motor without impairing the assembling workability.

An opening may be formed in the side wall so as to communicate the inside and outside of the yoke, and the control driving means and the outside of the yoke may be electrically connected through the opening.
Furthermore, the control driving means may be disposed inside the yoke in a state of being in direct contact with the side wall, so that the heat of the control driving means can be efficiently radiated by the yoke. At this time, the contact between the control drive means and the side wall is a concept including a form in which not only the control drive means housing surface but also a control drive element or a circuit element provided in an exposed state on the control drive means contacts the side wall. . In the above-described electric motor, the presence or absence of the brush does not matter.

Another electric motor of the present invention is an electric motor for supplying electric power using a brush, wherein a brush holder for accommodating the brush and a control driving means for controlling and driving the electric motor are integrally formed. I have. In this case, the unit in which the brush holder and the control driving means are integrated can be applied to the electric motor having the cylindrical yoke having the side wall at one end side as described above. In the motor, the sliding direction of the brush may be axial or radial.

On the other hand, the electric power steering apparatus of the present invention has a rack shaft connected to steering wheels, a rack shaft movably accommodated therein, and rack teeth formed on the rack shaft and a steering handle. A first housing that holds a coupling portion that meshes with a pinion of a steering shaft, an electric motor that is disposed coaxially around the rack shaft in the first housing, and that supplies a steering assist force to the rack shaft; A ball screw mechanism for connecting a nut connected to the armature shaft and a screw formed on the rack shaft with a ball member interposed therebetween and transmitting the rotational force of the electric motor to the rack shaft as steering assisting force, and a ball screw A second housing that accommodates the mechanism and is coupled to the first housing;
The second yoke of the motor is sandwiched in the first housing.
An electric power steering device provided on a portion opposite to an axial direction with respect to a housing, wherein control driving means for controlling and driving an electric motor is housed in a position adjacent to a power supply portion in a first housing. And

Thus, even in the case of an electric power steering device of a type in which the power supply portion is incorporated in the back of the first housing, the control drive means of the first power drive device can be used without impairing the assembling workability.
It can be provided integrally in the housing. In this case, an opening communicating with the inside and outside of the first housing may be formed facing the arrangement position of the control driving means, and the control driving means and the outside of the first housing may be electrically connected through the opening. . Further, it is possible to dispose the control drive means inside the yoke in a state of being in direct contact with the side wall of the first housing.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) FIG. 1 is an explanatory diagram showing a configuration of an electric motor according to an embodiment of the present invention. The motor 90 according to the present invention has a configuration in which a control drive element such as an FET or an ECU or various circuit elements are unitized to form a driver unit (control drive means) 91, which is housed and arranged inside the yoke 110. I have. FIG. 2 is an exploded perspective view showing the configuration of the driver unit 91, and FIG. 3 is a sectional view showing a state in which the driver unit 91 is mounted in the yoke 110.

As shown in FIG. 2, the driver unit 91 includes a brush holder 41, a print wire board (hereinafter abbreviated as PWB) 93, an insert wiring board (hereinafter abbreviated as IWB) 94 in a case 92, FET 95 as control drive element and FET push plate 96
Are housed together. In other words, the configuration is such that the driver of the control system is integrally disposed in a part of the brush holder 41, so that the wiring between the control device and the electric motor can be reduced, the noise can be reduced and the efficiency of the system can be increased. And so on.

However, the driver unit 91 does not necessarily need to have the brush holder 41 integrated. That is, the driver unit 91 according to the first embodiment includes the brush holder 41, but the control / drive unit according to the present invention includes a mode without the brush holder 41. Therefore, for example, in a brushless motor, a configuration excluding a brush holder portion is used, and this is a control driving unit.

Note that reference numeral 1 shown by a broken line in FIG.
A part 08 is a drive shaft of the electric motor 90.
The other parts than the driver unit 91 have the same configuration as that of a normal electric motor (motor), and the description thereof is omitted here.

In this case, the brush 2 is
3 are accommodated, and a terminal 97 is connected to the brush 23 via a pigtail 25. The terminal 97 has its end welded to the IWB 94, and
This connects between WB94. A circuit element such as a resistor is mounted on the PWB 93, and the connection hole 93a
Are connected to the connection terminals 94a of the IWB 94 and soldered. As a result, the PWB 93 and the IWB 94 are electrically connected and both are assembled. A spacer 98 is provided between the PWB 93 and the IWB 94.

On the right side of the IWB 94 in FIG. 2, an FET push plate 96 made of aluminum is mounted. FE
The T push plate 96 is provided with four FET accommodating portions 96a, and the FETs 95 are mounted thereon. in this case,
The FET 95 is mounted such that one surface thereof is exposed at the end surface of the driver unit 91 and slightly protrudes from the end surface. Also, as shown in FIG. 3, the terminal 95a of the FET 95 is drawn out from the FET accommodating portion 96a toward the IWB 94, extends to the back side of the IWB 94, and is soldered there. Further, the IWB 94 is provided with a power supply terminal 94b for supplying power and a signal terminal 94c for transmitting and receiving control signals.

The brush holder 41 is placed in the case 92.
After accommodating the PWB 93, the IWB 94, the FET 95, and the FET pressing plate 96, the inside is filled with a synthetic resin and potting is performed. Thereby, the durability of the driver unit 91 is ensured, and even when, for example, the electric motor 90 is used for a power steering device installed near the vehicle running surface, the driver unit 91 can be protected from impacts caused by stepping stones or the like.

The driver unit 91 having such a configuration is housed and arranged inside the end of the yoke 110 as shown in FIGS. In this case, one end of the yoke 110 is closed by the side wall 109, and the driver unit 91 is mounted such that one exposed surface of the FET 95 contacts the inner surface of the side wall 109. The driver unit 91 is fixed by screws 101 using the mounting holes 95b of the FET 95. As shown in FIG. 2, the brush holder 41, the PWB 93, the IWB 94, and the FET push plate 96 are each provided with an insertion hole at a position corresponding to the mounting hole 95b, and the screw 101 passes through the side wall 109 via these. Is screwed into the female screw hole 102 provided in the. That is, the driver unit 91 includes the FET
95 is fixed to the side wall 109 in a state where they are fastened together. Note that, as shown in FIG.
In the back side of the FET 95, an escape space is provided so that the FET 95 does not float from the side wall 109 due to dimensional variations.

As described above, in this motor 90, the FET
A driver unit 91 is mounted in a form in which 95 is sandwiched between an aluminum FET push plate 96 and a side wall 109. Moreover, one surface of the FET 95 is the yoke 1
10 so as to be in close contact with the side wall 109. Therefore, the heat generated from the FET 95 is quickly dissipated via the yoke 110 and the FET pressing plate 96 having good thermal conductivity,
The heat radiation of the driver unit 91 is ensured.

On the other hand, the side wall 109 is provided with a power supply opening 103 and a signal line opening 104 corresponding to the power supply terminal 94b and the signal terminal 94c. A power supply coupler 105 and a signal line coupler 106 are screwed outside these openings 103 and 104, respectively.
That is, in the motor 90, the driver unit 91 is accommodated inside the closed end face such as the side wall 109, and an opening is provided therein for electrical connection. An O-ring 1 is provided between each of the couplers 105 and 106 and the side wall 109.
07 (only the power supply coupler 105 is shown in FIG. 3) is interposed between the power supply opening 103 and the signal line opening 10.
The portion 4 is sealed in a watertight manner. These couplers 105 and 106 may be male or female.

On the other hand, the electric motor 90 according to the present invention is assembled as follows. Here, first, the assembled driver unit 91 is inserted into the yoke 110 through the opening at the left end in FIG. At this time, the power supply terminal 94b is inserted into the power supply opening 103, and the signal terminal 94c is inserted into the signal line opening 104.

Next, this driver unit 91 is
01 is fixed. At this time, since the exposed surface of the FET 95 slightly protrudes from the end surface of the case 92, as shown in FIG.
9 Contact the inner surface. The FET 95 is fastened together by the screw 101 and is fixed to the side wall 109 in a state of being in close contact therewith.

On the outer surface side of the side wall 109, the power supply opening 10
3 and the signal line opening 104, respectively.
And the signal terminal 94c protrudes. Therefore, a power supply coupler 105 and a signal line coupler 106 are screwed into these openings 103 and 104 with an O-ring 107 interposed therebetween. Thus, in this electric motor 90, the brush holder 4
1 and the control drive system are unitized, so that the configuration of the power supply system and the signal system can be constructed only by the work of screwing the driver unit 91 into the yoke 110 and the work of screwing the coupler outside the yoke 110.

Then, an armature, a field device and the like are inserted into the yoke 110 to complete the assembly. In the electric motor 90, a so-called disc-type commutator is used as a commutator, and the brush 23 is in sliding contact with the right end face thereof in the axial direction. This is because the electric motor 90 has a configuration in which the brush 23 is incorporated in the back of the yoke 110, and therefore it is difficult to assemble a brush that slides in a radial direction.

As described above, in the electric motor 90 according to the present invention, the electric power supply unit 13 of the electric motor 1 can be easily assembled even if it is not in the opening. The degree of freedom above also increases.

(Embodiment 2) Next, as Embodiment 2, an electric power steering apparatus using an electric motor according to an embodiment of the present invention will be described. FIG. 4 is an explanatory view showing the entire configuration of the electric power steering device, a part of which is shown in cross section. The same members and components as those of the electric motor 90 according to the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 4, the electric power steering device (hereinafter, abbreviated as power steering device) includes a hollow electric motor 1 and a rack shaft 2 similar to the conventional power steering device shown in FIG.
, For example, and is attached as a steering device for steering wheels such as front wheels of an automobile. And
The steering assist force generated by the electric motor 1 is transmitted to the rack shaft 2 via the ball screw mechanism 3 to reduce the driver's steering burden.

As shown in FIG. 4, the power steering apparatus has a configuration in which a housing A (first housing) and a housing B (second housing) integrated with a yoke 7 of the electric motor 1 are connected. The rack shaft 2 is slidably mounted in the rack shaft 2 in the left-right direction. The wheels are connected to both ends of the rack shaft 2 via tie rods, knuckle arms, and the like in a state where the rack shaft 2 is attached to the vehicle main body by a bracket (not shown) and the mounting hole 10 of the housing B.

On the other hand, the housing A is a hollow member made of aluminum die cast, and a cylindrical motor yoke (hereinafter abbreviated as yoke) 7 is integrally cast into the housing A. Further, on the right end side of the housing A in FIG. 4, a coupling portion 6 between the steering shaft 5 connected to the steering wheel and the rack shaft 2 is formed. In the connecting portion 6, a pinion (not shown) provided on the steering shaft 5 and a rack tooth (not shown) formed on a side portion of the rack shaft 2 mesh with each other. Is converted to left and right movement. A torque sensor (not shown) for detecting the rotational torque of the steering shaft 5 is provided on the shaft of the connecting portion 6, and the auxiliary steering force of the electric motor 1 is controlled based on the detected value.

Next, the motor 1 has a configuration in which a hollow cylindrical armature shaft 11 and a field device 12 are coaxially inserted into a cylindrical yoke 7. Then, the rack shaft 2 is assembled so as to pass through the inside of the armature shaft 11. The field device 12 is composed of a magnet 14 attached to the inner periphery of the yoke 7 and an armature core 15 attached to the outer periphery of the armature shaft 11. Is supplied with power. Further, the yoke 7 is a cylindrical member made of iron, is formed with a substantially constant thickness by a cylindrical pipe, and is in a state of being cast into the housing A as described above.

In the power steering apparatus shown in FIG.
Are integrally cast into the housing A, and the yoke 7 of the electric motor 1 itself does not have the side wall 109 unlike the electric motor 90. However, when assembling the motor 1, the side wall 100 of the housing A is substantially a barrier similar to the side wall provided at one end of the yoke 7, and the motor 90 according to the first embodiment is improved in terms of assemblability. Has the same problems as

A plurality of magnets 14 as field poles constituting the field device 12 are arranged inside the yoke 7 at intervals in the circumferential direction. One end (right end in FIG. 4) of the armature shaft 11 is held by a bearing 17 attached to the housing A. Also,
A tapered spline is formed on the other end side (the left end in FIG. 4), and the armature shaft 11 is resiliently pressed to one end side (the left side in FIG. 4) by an unillustrated resilient member, and a nut portion of the ball screw mechanism 3 is formed. The end of 19 is fitted with a spline similarly formed. As a result, the rotation of the armature shaft 11
Is transmitted to

The power supply section 13 is a section for supplying electric power to the armature, and has a configuration in which a commutator 22 fixed to the armature shaft 11 and a brush 23 which is an electrical contact with the commutator 22 are provided. In the power steering device, a so-called disc-type commutator is used as the commutator 22 for the same reason as that of the electric motor 90, and the brush 23 is in sliding contact with the right end face in the axial direction.

Here, in the power steering apparatus according to the present invention, a driver unit (control driving means) 91 for controlling and driving the electric motor 1 is mounted adjacent to the power supply section 13 so as to be accommodated in the housing A. ing. That is, the control drive unit is unitized here and is built in the power steering device. FIG. 5 is an explanatory diagram showing an attached state of the driver unit 91.

In this case, the driver unit 91 is configured as shown in FIG.
Are formed in the same configuration as that shown in FIG. The driver unit 91 is accommodated and arranged in the large-diameter portion 99 of the housing A as shown in FIG. At this time, the driver unit 91 is inserted from the opening of the joint portion of the housing A and the housing B formed to the left in FIGS. One end of the large-diameter portion 99 is closed by a side wall 100, and the driver unit 91
It is attached so that one exposed surface of the FET 95 abuts on the inner surface. In addition, the driver unit 91 includes the FET 9
5 and is fixed by screws 101 using the mounting holes 95b. These states are the same as FIG. 3 except that the yoke 7 corresponds to the housing A and the side wall 109 corresponds to the side wall 100.

Accordingly, in the power steering apparatus, similarly to the electric motor 90, heat generated from the FET 95 is quickly radiated through the housing A having good heat conductivity and the FET pressing plate 96, and the heat radiation of the driver unit 91 is reduced. Will be secured. Further, by using the driver unit 91, the wiring between the control device and the electric motor can be reduced in the power steering device as well, and it is possible to reduce noise and increase the efficiency of the system. .

Next, the housing B is a hollow member made of aluminum die-cast similarly to the housing A, and has a ball screw mechanism 3 incorporated therein. The ball screw mechanism 3 includes a nut 19, a screw 30 formed on the outer periphery of the rack shaft 2, the nut 19 and the screw 3.
0 and a number of balls 31 interposed therebetween. The rack shaft 2 is supported by the nut portion 19 so as to be reciprocally movable in the left-right direction while the rotation around the shaft is restricted, and moves in the left-right direction with the rotation of the nut portion 19.

The nut portion 19 is held rotatably around the axis with respect to the housing B via an angular bearing 4 fixed to the housing B. That is, in the power steering apparatus, the nut portion 19 of the ball screw mechanism 3, the rack shaft 2, and the angular bearing 4 are integrated and provided in a housing B formed separately from the housing A. It has become.

On the other hand, the housing A of the power steering apparatus is assembled as follows. Similarly to the motor 90 described above, the assembled driver unit 91 is moved from the opening at the left end of the housing A in FIG.
To the back. At this time, the power supply terminal 94b is provided in the power supply opening 103, and the signal terminal 94c is provided in the signal line opening 104.
Insert Next, this driver unit 91 is
01 is fixed. At this time, the FET 95 is connected to the screw 101
And is fixed to the side wall 100 in a tightly contacted state. Further, a power supply coupler 105 and a signal line coupler 106 are inserted into the openings 103 and 104 of the side wall 100, respectively.
7 and screw it in. As described above, also in the power steering device, the power supply system and the signal system can be constructed only by the screwing work of the driver unit 91 and the coupler.

Then, the armature or the field device 1
2 and the like are inserted into the housing A, and the assembly of the electric motor 1 is completed. The yoke 7 is already cast in the housing A. Thus, in the power steering device, the electric motor 1
Can be easily assembled even if the power supply unit 13 is not located in the opening, and the workability of the assembly is greatly improved, and the restrictions on the assembly are eliminated, and the degree of freedom in design is increased.

The power steering device operates as follows. That is, first, the steering handle is operated to rotate the steering shaft 5, and the rack shaft 2 moves in a direction corresponding to the rotation to perform the steering operation. When a steering torque sensor (not shown) is operated by this operation, a signal is transmitted to the driver unit 91, and the driver unit 91 supplies power to the commutator 22 via the brush 23 according to the detected torque. As a result, the electric motor 1 operates to rotate the armature shaft 11, and the nut 19 connected thereto also rotates. When the nut portion 19 rotates, the steering assist force is transmitted to the rack shaft 2 by the action of the ball screw mechanism 3, and the movement of the rack shaft 2 is promoted, and the steering force is assisted.

The present invention is not limited to the above-described embodiment, and it goes without saying that various changes can be made without departing from the scope of the invention.

For example, the above-described electric motor is of a type in which electric power is supplied by using a brush, but a configuration in which a driver unit is housed in a yoke or a housing can also be adopted in a brushless motor. Further, in the above-described embodiment, the brush is slid from the axial direction using a disk type commutator as the electric motor. However, the present invention is applied to an electric motor in which the brush moves in the radial direction and slides on the commutator from the radial direction. It is also possible to apply

On the other hand, in the above-described example, the FET is exposed to the driver unit and one side thereof is directly applied to the side wall. However, the FET is mounted on the back of a metal plate having good heat conductivity such as aluminum or copper.
An element such as ET may be provided, and the front side of the metal plate may be exposed and applied to the side wall. Further, an element such as an FET may be arranged on the outer peripheral surface of the driver unit, and may be applied to the yoke or the cylindrical portion of the housing to radiate heat.

[0051]

According to the present invention, in a motor having a cylindrical yoke having a side wall at one end, a driver unit is accommodated at an end on the side wall side inside the yoke, so that the power supply portion is disposed at the back of the yoke. Even in this case, the control drive unit can be provided integrally with the electric motor without impairing the assembling workability.

Further, since the driver unit is disposed inside the yoke in a state of being in direct contact with the side wall, the heat of the control drive element such as an FET can be efficiently radiated through the yoke. Furthermore, by forming the driver unit including the brush holder, the configuration of the power supply unit can be simplified.

On the other hand, in the electric power steering device in which the power supply unit is provided at the back of the housing, the driver unit is accommodated in the housing at a position adjacent to the power supply unit.
Even with this type of electric power steering device, the driver unit can be provided integrally with the housing without impairing the assembling workability.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of an electric motor according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a configuration of a driver unit.

FIG. 3 is a sectional view showing a state in which a driver unit is mounted in a yoke.

FIG. 4 is an explanatory diagram showing a partial cross section of the entire configuration of an electric power steering apparatus using an electric motor according to an embodiment of the present invention.

FIG. 5 is an explanatory view showing an attached state of a driver unit in the electric power steering device of FIG. 4;

FIG. 6 is an explanatory view showing a part of the entire configuration of a conventional electric power steering device in cross section.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Motor 2 Rack shaft 3 Ball screw mechanism 4 Angular bearing 5 Steering shaft 6 Coupling part 7 Motor yoke 10 Mounting hole 11 Armature shaft 12 Field device 13 Feeding part 14 Magnet 15 Armature core 17 Bearing 19 Nut part 22 Commutator 23 Brush 25 Pigtail 30 Screw part 31 Ball 41 Brush holder 51 Rack shaft 52 Electric motor 53 Ball screw mechanism 54 Steering shaft 55 Yoke 56 Armature shaft 57 Field device 58 Feeding part 59 Magnet 60 Armature core 61 Brush 62 Commutator 63 Brush holder 64 Pigtail 65 Terminal plate 66 Housing 67 Coupler 90 Motor 91 Driver Unit (Control Driving Means) 92 Case 93 Printed Wire Board 93a Connection Hole 94 Insert wiring board 94a Connection terminal 94b Power supply terminal 94c Signal terminal 95 FET 95a Terminal 95b Mounting hole 96 FET push plate 96a FET housing part 97 Terminal 98 Spacer 99 Large diameter part 100 Side wall 101 Screw 102 Female screw hole 103 Power supply opening 104 Signal Line opening 105 Power supply coupler 106 Signal line coupler 107 O-ring 108 Drive shaft 109 Side wall 110 Yoke A housing (first housing) B housing (second housing)

Continued on the front page (72) Inventor Wataru Mochizuki 1-268, Hirosawa-cho, Kiryu-shi, Gunma Mitsuba F-term (reference) 3D033 CA03 CA04 5H605 AA08 BB05 CC08 DD09 GG06 5H611 AA00 BB01 TT01 UA01 UB01

Claims (5)

[Claims] 1. An electric motor having a cylindrical yoke having a side wall at one end, and a control drive means for controlling and driving the electric motor is housed at an end of the yoke inside the side wall. An electric motor characterized by: 2. The electric motor according to claim 1, wherein the side wall has an opening formed so as to communicate between the inside and the outside of the yoke, and the control drive unit and the yoke via the opening. An electric motor characterized by being electrically connected to the outside. 3. The electric motor according to claim 1, wherein said control drive means is disposed inside said yoke in a state of being in direct contact with said side wall. 4. An electric motor for supplying electric power by using a brush, wherein a brush holder accommodating the brush and a control driving means for controlling and driving the electric motor are integrally formed. 5. A rack shaft connected to a steering wheel, the rack shaft being movably accommodated, and a rack tooth formed on the rack shaft meshed with a pinion of a steering shaft connected to a steering handle. A first housing for holding the coupling portion, an electric motor disposed coaxially around the rack shaft in the first housing, for supplying a steering assist force to the rack shaft, and being connected to an armature shaft of the electric motor. A ball screw mechanism that connects the nut portion and the screw portion formed on the rack shaft with a ball member interposed therebetween and transmits the rotational force of the electric motor to the rack shaft as steering assisting force; and the ball screw. A second housing that houses a mechanism and is coupled to the first housing, wherein a power supply unit of the motor is disposed within the first housing with a yoke of the motor interposed therebetween. An electric power steering device provided in a portion on the opposite side of the second housing in the axial direction, wherein a control drive unit for controlling and driving the electric motor is provided in a position adjacent to the power supply unit in the first housing. An electric power steering device characterized by being housed in a vehicle.