JP7423356B2 - motor control device - Google Patents

Description

The present invention relates to a motor control device that controls an electric motor.

2. Description of the Related Art Conventionally, techniques relating to a motor control device for controlling an electric motor, which is provided by integrating an electric motor and a circuit for controlling the electric motor, have been known. For example, Patent Document 1 discloses an electronic control device that allows various other terminals to be connected to terminals provided on a circuit board with sufficient connection reliability, contributing to miniaturization of the device. This control device has a case and a cover that are joined to each other, a drive circuit board that drives a motor unit is fixed to the cover, and a control circuit board that controls the drive circuit board is fixed to the case. An electrical connector that supplies power to each board and motor unit is attached to the opening of the case, and the energizing terminal of this electrical connector and the energizing terminal provided on the drive circuit board connect the case and cover. directly electrically connected.

Further, Patent Document 2 discloses a drive device that does not require special and large-scale equipment and can non-destructively disassemble the motor and control unit. In this drive device, the heat sink of the control unit is fixed to the cover. The coil of the motor has a lead wire that passes through the housing and extends toward the control unit. The board has a connector detachably connected to the lead wire. This eliminates the need for soldering or welding when electrically connecting the motor and control unit. The connection is completed by inserting the lead wire into the connector. Therefore, special and large-scale equipment is not required. Further, even after assembly, the motor and control unit can be disassembled non-destructively by separating the motor and control unit so that the connector is removed from the lead wire.

Japanese Patent Application Publication No. 2017-152389 JP2018-122665A

The above-described conventional technology has a structure in which a terminal (male terminal) extending from a motor or the like is fitted into a terminal (female terminal) mounted on a board, thereby electrically connecting the two. However, in this structure, when attaching both, the entire load that the male terminal applies to the female terminal is applied to the board, so there is a concern that cracks may occur in the soldered part that joins the female terminal and the board. There is.

The present invention has been devised in view of the above circumstances, and provides motor control for a removable electric motor that reduces the load applied to the joint between the terminal and other components during assembly and has high connection reliability. It provides equipment.

In order to solve the above-mentioned problems, we developed a motor control system that includes a motor housing that accommodates an electric motor, a circuit board that mounts electronic components for controlling the electric motor, and a control unit that is detachably attached to the motor housing. The apparatus includes a motor housing having a first terminal electrically connected to the electric motor and extending toward a control unit, the control unit having a second terminal connected to the first terminal when installed. and a board holding member having a board holding part that holds at least two circuit boards facing each other in the mounting/detaching direction and a terminal holding part holding the second terminal, the terminal holding part having a terminal holding part that holds at least two circuit boards facing each other in the mounting/detaching direction. The terminal holding part is provided between at least two circuit boards and on the outer periphery of the board holding member, and the terminal holding part has a load that supports the load in the attachment/detachment direction that occurs when the first terminal is inserted into and removed from the second terminal. A motor control device is provided having a support formed therein.
According to this, the load support part that receives the load in the attachment/detachment direction that occurs when the first terminal is inserted into or removed from the second terminal is formed on the board holding member other than the circuit board, so that the load that is generated when the first terminal is inserted into or removed from the second terminal is It is possible to provide a removable motor control device for an electric motor that reduces the load applied to joints with other members such as circuit boards and other terminals, and has high connection reliability.

Further, the at least two circuit boards include a first circuit board held at one end of the board holding member, and a second circuit board held at the other end of the board holding member and disposed closer to the electric motor than the first circuit board. The second circuit board may have a hole for connection to the second terminal, and one end of the second terminal may pass through the hole for connection and be joined.
According to this, the second terminal is bonded to the circuit board, but by supporting the load applied to the second terminal with the board holding member that supports the circuit board, the load between the second terminal and the circuit board that occurs during assembly is reduced. The load applied to the joint can be reduced.

Further, the at least two circuit boards include a first circuit board held at one end of the board holding member, and a second circuit board held at the other end of the board holding member and disposed closer to the electric motor than the first circuit board. The first circuit board has a terminal for connection to the second terminal extending toward the electric motor, and one end of the second terminal is electrically connected to the connection terminal. You can also use it as
According to this, the second terminal is electrically connected to the connection terminal extending from the circuit board, and the load applied to the second terminal is supported by the board holding member that supports the circuit board, so that assembly is possible. It is possible to reduce the load that is sometimes applied to the joint between the second terminal and the connection terminal.

Furthermore, a plurality of terminal holding parts are arranged in a direction orthogonal to the attachment/detachment direction, and the load support part supports the second terminal formed in a direction perpendicular to both the attachment/detachment direction and the direction orthogonal to the attachment/detachment direction from both sides. The second terminal may include an insertion piece that is inserted into the support groove.
According to this, the second terminal is efficiently supported.

Furthermore, the electric motor may be used for electric power steering mounted on a vehicle.
According to this, it is possible to provide a removable motor control device for electric power steering that reduces the load applied to the joint between the terminal and other members during assembly and has high connection reliability.

As described above, according to the present invention, it is possible to provide a detachable motor control device for an electric motor that reduces the load applied to the joint between the terminal and other components during assembly and has high connection reliability. be able to.

(A) Plan view, (B) Right side view, (C) Front view, (D) Perspective view from above, (E) Perspective view from below of the electric power steering device according to the first embodiment of the present invention. figure. (A) A plan view, (B) A cross-sectional view taken along the line BB in (A), and (C) A cross-sectional view taken along the line A-A in (A) of the electric power steering device according to the first embodiment of the present invention. . FIG. 1A is an exploded perspective view from above, and FIG. 3B is an exploded perspective view from below, of an electric power steering device according to a first embodiment of the present invention. FIG. 2 is a side view showing the attachment/detachment direction during assembly of the electric power steering device according to the first embodiment of the present invention. FIG. 1 is a perspective view of an electric power steering device according to a first embodiment of the present invention. (A) A perspective view of a motor housing and (B) a perspective view of a control unit in an electric power steering device according to a first embodiment of the present invention. FIG. 1 is a perspective view of the control unit of the electric power steering device according to the first embodiment of the present invention, as viewed from the board side. (A) A perspective view of a plurality of assembled boards, and (B) a perspective view of a heat sink cover in an electric power steering device according to a first embodiment of the present invention. (A) A perspective view of assembled multiple boards with motor connection terminals inserted, (B) assembled board with motor connection terminals inserted, in the electric power steering device of the first embodiment according to the present invention. FIG. 3 is a perspective view of multiple boards (with the cover removed). FIG. 2 is a perspective view of a plurality of assembled boards in a state in which motor connection terminals are not inserted in the electric power steering device according to the first embodiment of the present invention. FIG. 2 is a perspective view of a substrate holding member of the electric power steering device according to the first embodiment of the present invention. In the electric power steering device of the first embodiment of the present invention, (A) a perspective view showing a state in which the holding member connection terminal is attached to the board holding member, (B) a perspective view showing the state in which the holding member connection terminal is removed from the board holding member A perspective view showing the state. (A) A perspective view showing a state in which a holding member connection terminal is being attached to a board holding member, and (B) an enlarged perspective view thereof, in an electric power steering device according to a first embodiment of the present invention. (A) A front view, (B) a left side view, (C) a rear view, and (D) a perspective view of a holding member connection terminal in the electric power steering device according to the first embodiment of the present invention. (A) A perspective view showing a state in which a motor connection terminal is inserted into a holding member connection terminal, and (B) an enlarged perspective view thereof, in an electric power steering device according to a first embodiment of the present invention. (A) A plan view showing a state in which a board holding member and a drive board are assembled, and (B) a cross-sectional view taken along the line CC in (A) in an electric power steering device according to a second embodiment of the present invention. (A) A perspective view showing a state in which a board holding member and a drive board are assembled, (B) an enlarged perspective view thereof, and (C) a perspective view of a drive board 130 in an electric power steering device according to a second embodiment of the present invention. . (A) A perspective view showing the assembled state of the board holding member and the drive board (with the cover attached), (B) the board holding member, the drive board, and the power supply in the electric power steering device of the second embodiment of the present invention FIG. 3 is a perspective view showing the assembled state of the board. FIG. 1 is a functional block diagram of an electric power steering device according to an embodiment of the present invention.

Embodiments of the present invention will be described below with reference to the drawings.
<First example>
The electric power steering device 1 in this embodiment will be described with reference to FIGS. 1 to 15 and 19. FIG. The electric power steering device 1 includes a motor housing 200 that accommodates an electric motor MT that drives a steering mechanism for a vehicle, and a plurality of circuit boards that mount electronic components for controlling the electric motor MT. and a control unit 100 that is detachably attached. The electric motor MT generates assist steering torque to the steering mechanism in order to assist the driver of the vehicle with torque when rotating the steering wheel. Control unit 100 is a control device for controlling electric motor MT that generates assist steering torque. In this embodiment, the electric power steering device 1 will be described, but the present invention is not limited to this, and other motor control devices including an electric motor that generates driving force and a control unit that controls the electric motor may be used. good.

In the electric power steering device 1 in this embodiment, as shown in FIG. 19, the electric motor MT is composed of a first electric motor MTA and a second electric motor MTB, and the control unit 100 is composed of a first control system 100A and a second control system. It consists of 100B. The electric power steering device 1 as a whole includes a first system 10A consisting of a first electric motor MTA and a first control system 100A, and a second system 10B consisting of a second electric motor MTB and a second control system 100B. Consisting of In this way, since each of the two systems is redundant, even if an abnormality occurs in either system, control as the electric power steering device 1 can be continued. In this embodiment, the first electric motor MTA and the second electric motor MTB have a redundant system because their windings are composed of a first winding set and a second winding set, and they share a rotor. ing. However, the present invention is not limited thereto, and the first electric motor MTA and the second electric motor MTB may be two separate electric motors.

As shown in FIGS. 1 and 19, the first control system 100A/second control system 100B is connected to a power supply electronic component 151 that constitutes a power supply section on a power supply board 150 from a vehicle battery via a power cable and a power connector 1111. (shown in Figure 3). The power connector 1111 is connected to a power terminal 112 formed on the substrate side of the connector assembly 110. In addition, the first control system 100A/second control system 100B configures a control unit on the control board 160 via a CAN connector 1112 that is connected to a CAN (Car Area Network, not shown) via a control cable. A vehicle speed signal is supplied to the microcomputer 162 that Further, the first control system 100A/second control system 100B supplies a steering torque signal, a steering angle signal, etc. to the microcomputer 162 via a sensor connector 1113 connected to a sensor that detects information on various parts of the vehicle. The sensor connector 1113 is connected to a control terminal 113 formed on the substrate side of the connector assembly 110. The control terminal 113 is arranged radially outward of the output shaft RT from the power supply terminal 112.

The driver IC, which is the drive electronic component 131 on the drive board 130, receives a control signal from the microcomputer 162 on the control board 160 and drive power from the power supply section on the power supply board 150, and connects each motor connection terminal 210. The first electric motor MTA and the second electric motor MTB are driven through the motor. An MR sensor 161 (Magnetic Resistance sensor) that detects the rotational position of the rotor of the first electric motor MTA/second electric motor MTB is provided on the control board 160 and inputs the detected motor rotation angle signal to the microcomputer 162. . In this way, the connectors 111 such as the power connector 1111 and the CAN connector 1112, the control board 160, the drive board 130, and the power board 150 have redundant systems corresponding to the first electric motor MTA and the second electric motor MTB, respectively. As shown in FIG. 1(A), the control unit 100 is divided into a first control system 100A and a second control system 100B above and below a center line CT connecting the center of the sensor connector 1113 and the rotation axis of the electric motor MT. It is located. Even in the case where there is a redundant system and a large number of parts, by arranging it in this manner, it is possible to provide a compact electric power steering device 1.

The motor housing 200 includes a motor connection terminal 210 (first terminal) that is electrically connected to the electric motor MT. Motor connection terminal 210 extends toward control unit 100, is electrically connected to the board, and transmits a drive current for driving electric motor MT. Since the electric motor MT has three phases, the motor connection terminals 210 form a set of three terminals, and as shown in FIG. 2(B), two terminals correspond to the first control system 100A and the second control system 100B, respectively. Consists of pairs.

As shown in FIG. 3, the control unit 100 includes, in order from the motor housing 200 housing the electric motor MT, a connector assembly 110, a heat sink cover 120, a drive board 130 (first circuit board), a board holding member 140, and a power supply board. 150 (second circuit board) and a control board 160.

The connector assembly 110 is disposed at the farthest position from the motor housing 200 that accommodates the electric motor MT, and has a plurality of connectors 111 formed therein for connection to external cables such as a battery, CAN, and sensor. The connector 111 includes a power connector 1111, a CAN connector 1112, and a sensor connector 1113 corresponding to external cables. The heat sink cover 120 mounts the connector assembly 110 on about 2/3 of its upper surface, is fixed to the motor housing 200, and radiates heat generated by the plurality of boards on the remaining upper surface and side surfaces.

In order to drive the electric motor MT, the drive board 130 includes a pre-driver that generates a PWM signal from the control signal of the microcomputer 162, and a pre-driver that generates a PWM signal from the control signal of the microcomputer 162, and a pre-driver that generates a first winding set and a second winding set of the three-phase electric motor MT using the PWM signal. It is equipped with drive electronic components 131 including a bridge circuit composed of switching elements to be driven, a shunt resistor for detecting the current of each phase of the bridge circuit, and the like. Further, the drive board 130 has a power drive terminal 132 that is electrically connected to the power supply board 150 . The drive board 130 is arranged with the surface on which these drive electronic components 131 are mounted facing the power supply board 150 (substrate holding member 140), and the surface opposite to this surface facing the heat sink cover 120 side.

The power supply board 150 mounts a power supply electronic component 151 for generating power to the drive board 130. The power supply electronic component 151 constitutes a power supply section for converting the power from the battery obtained through the power supply connector 1111 into a power supply suitable for the electric motor MT and the microcomputer 162 on the control board 160. The power supply board 150 is arranged closer to the electric motor MT than the drive board 130 in the axial direction of the output shaft RT, with the surface on which the power supply electronic component 151 is mounted facing the drive board 130 side. Note that the power supply electronic components 151 may be mounted on both sides of the power supply board 150.

The control board 160 has a rotation sensor 161 (MR sensor 161) for detecting the rotation of the rotating shaft of the electric motor MT on one surface, and a microcomputer 162 (see FIG. (not shown in Figure 3). The control board 160 is arranged closer to the electric motor MT than the power supply board 150 in the axial direction of the output shaft RT, with the surface on which the rotation sensor 161 is mounted facing the electric motor MT side. In this embodiment, the control board 160 is fixed to a support formed on the heat sink cover 120 with screws.

The substrate holding member 140 has holding parts 141 (substrate holding parts) that hold the drive board 130 and the power supply board 150 at a predetermined distance at four corners of the rectangular part. The holding part 141 holds the drive board 130 and the power supply board 150, which are two circuit boards, in a state where they face each other in the axial direction of the output shaft RT. In this embodiment, the holding unit 141 holds two sheets, the drive board 130 and the power supply board 150, but is not limited to this, and may also hold the control board 160, for example. The predetermined distance is a distance such that the tallest component among the drive electronic component 131 and the power supply electronic component 151 does not come into contact with the opposing substrate. One end of the holding portion 141 is fixed to the surface of the power supply board 150 on which the power supply electronic component 151 is mounted, and the other end is fixed to the surface of the drive board 130 on which the drive electronic component 131 is mounted.

The substrate holding member 140 has a holding member connection terminal 143 (second terminal) connected to the motor connection terminal 210. The board holding member 140 includes a holding member connection terminal 143 to which the motor connection terminal 210 (first terminal) is connected in order to assemble the control unit 100 and the motor housing 200. Thereby, when pushing the motor connection terminal 210 into the holding member connection terminal 143, the driving board 130 and the power supply board 150 can be maintained at a predetermined distance. Further, the substrate holding member 140 has a terminal holding part 142 that holds the holding member connection terminal 143. The details will be described later. Further, the board holding member 140 includes a press-in cover 146 for protecting the holding member connecting terminal 143 and guiding the motor connecting terminal 210 when the motor connecting terminal 210 is pushed into the holding member connecting terminal 143.

As shown in FIG. 4, the control unit 100 and the motor housing 200, in which the connector assembly 110, the heat sink cover 120, the drive board 130, the board holding member 140, the power board 150, and the control board 160 are assembled together, are assembled as shown in FIG. It is attached and detached in the direction of the arrow (axial direction of the output shaft RT). When both are assembled, the motor connection terminal 210 is inserted into the holding member connection terminal 143 provided on the board holding member 140, and when both are disassembled, the motor connection terminal 210 is pulled out from the holding member connection terminal 143. . In this manner, the motor connection terminal 210 is inserted into and removed from the holding member connection terminal 143 in the attachment/detachment direction.

5 to 15, substrate holding member 140 includes holding member connection terminal 143, terminal holding portion 142 that holds it, support groove 147 (load support portion) that supports holding member connection terminal 143, etc. I will explain about it. FIG. 5 is a perspective view of the electric power steering apparatus 1 in which the motor housing 200 and the control unit 100 are assembled, as viewed from the control unit 100. FIG. 6 is a perspective view showing the motor housing 200 and the control unit 100 separately when viewed from the same viewpoint as FIG. Exposed inside the motor housing 200 are two sets of motor connection terminals 210 extending from the electric motor MT toward a plurality of circuit boards stacked in the axial direction of the output shaft RT included in the control unit 100. There is.

FIG. 7 is a perspective view of the control unit 100 viewed from the side of a plurality of stacked circuit boards. Note that in this figure, the control board 160 is omitted, so the power supply board 150 is shown at the top. The power supply board 150 has a connection hole 152 into which a part of the holding member connection terminal 143 is inserted and joined, and a connection hole 152 into which a part of the connection terminal 133 (shown in FIG. 3) provided on the drive board 130 is inserted. It has a connecting terminal hole 153 for joining by connecting the wire. This figure shows a part of the holding member connection terminal 143 (joint piece 1432 shown in FIG. 14) being inserted and joined into the connection hole 152 of the power supply board 150, and the connection terminal of the power supply board 150. The connection terminal 133 is shown inserted into the hole 153 and joined. 7 shows a state in which the motor connection terminal 210 is inserted into the circuit board for the sake of explanation, and the motor connection terminal 210 passes through two sets of three holes drilled in the power supply board 150. ing.

FIG. 8 shows the control unit 100 in a state in which the drive board 130 and the power board 150 are assembled in the mounting/removal direction (RT) on the board holding member 140, and a state in which the heat sink cover 120 on which the connector assembly 110 is mounted is separated. ing. On the upper surface of the power supply board 150, a part of one end (joint piece 1432 shown in FIG. 14) of the holding member connection terminal 143 passes through the connection hole 152 from below and is soldered. Further, on the upper surface of the power supply board 150, the connection terminals 133 mounted on the drive board 130 from below penetrate through the connection terminal holes 153 and are soldered. The connection hole 152 and the connection terminal hole 153 are electrically connected by a wiring pattern formed on the power supply board 150. Thereby, the bridge circuit of the drive board 130 is electrically connected to the electric motor MT via the holding member connection terminal 143 and the motor connection terminal 210. Note that in FIG. 8 as well, the control board 160 is omitted and the motor connection terminal 210 is shown inserted into the circuit board.

FIG. 9 shows a state in which the drive board 130 and the power supply board 150 are assembled to the board holding member 140 in the attachment/detachment direction, and the motor connection terminal 210 is inserted into the board holding member 140. When the drive board 130, the board holding member 140, and the power supply board 150 are assembled, a press-in cover 146 that protects the holding member connection terminal 143 is attached as shown in this figure (A). On the other hand, this figure (B) shows a state in which the press-in cover 146 is removed, and a state in which the motor connection terminal 210 is inserted into the holding member connection terminal 143 provided on the side surface of the board holding member 140. ing.

FIG. 10 shows a state in which the motor connection terminal 210 is not inserted, and the drive board 130, the board holding member 140, and the power supply board 150 are stacked and assembled in the attachment/detachment direction. The drive board 130 is held at one end of the board holding member 140, and the power supply board 150 is held at the other end of the board holding member 140. In this state, it is fixed to the heat sink cover 120. In this embodiment, the drive board 130 is fixed to the heat sink cover 120 with screws. Note that after fixing the drive board 130 to the board holding member 140, the drive board 130 may be fixed to the heat sink cover 120 with screws, and then the power supply board 150 may be fixed to the board holding member 140.

FIG. 11 shows only the substrate holding member 140 with the driving substrate 130 and the power supply substrate 150 removed from a state in which the drive substrate 130, the substrate holding member 140, and the power supply substrate 150 are stacked and assembled in the attachment/detachment direction. The substrate holding member 140 includes a holding portion 141 (substrate holding portion), a holding member connecting terminal 143 (second terminal), and a press-in cover 146. The holding part 141 is fixed to the power supply board 150 at one end and to the drive board 130 at the other end, and holds the drive board 130 and the power supply board 150 in a state where they face each other in the attachment/detachment direction between the two boards. The press-in cover 146 protects and covers the holding member connection terminal 143, and has three holes (one per hole) provided on the top surface so as to guide the motor connection terminal 210. Each holding member connection terminal 143 has one end (joint piece 1432) branched into two from each terminal, and a portion connected to the motor connection terminal 210 is covered with a press-in cover 146.

FIG. 12 shows the substrate holding member 140 with the press-in cover 146 removed. This figure (A) shows a state in which the holding member connection terminal 143 is attached to the board holding member 140, and this figure (B) shows a state in which the holding member connection terminal 143 is removed from the board holding member 140. It shows. The board holding member 140 has a plurality of terminal holding parts 142 arranged on the side surface at positions corresponding to the motor connection terminals 210 in a direction perpendicular to the attachment/detachment direction. It surrounds four sides (bottom, back, and both sides) and is provided so as to accommodate the holding member connection terminal 143. Further, the terminal holding portion 142 is provided so as to be located between two circuit boards, the drive board 130 and the power supply board 150, which are stacked in the mounting/detaching direction.

FIG. 13 shows a state in which the holding member connection terminal 143 is being attached to (or removed from) the terminal holding part 142. This figure (B) is an enlarged view of one holding member connecting terminal 143 and one terminal holding part 142. In the terminal holding portion 142, support grooves 147 (load supporting portions) for supporting both sides (both side surfaces) of the holding member connection terminal 143 are formed. The support groove 147 is formed so that a part (insertion piece 1431) of the holding member connection terminal 143 can be inserted, and by sliding and inserting the holding member connection terminal 143 into the support groove 147, the substrate holding member 140 is inserted. Can be assembled. The support groove 147 is formed in a direction perpendicular to both the attachment/detachment direction and the direction orthogonal to the attachment/detachment direction in the terminal holding portion 142 arranged on the side surface (outer periphery) of the board holding member 140 in a direction orthogonal to the attachment/detachment direction. There is. Thereby, the holding member connection terminal 143 is efficiently supported by the terminal holding part 142.

As shown in FIG. 14, the holding member connection terminal 143 includes an insertion piece 1431 that is inserted into the support groove 147 and supported, a joint piece 1432 that is fitted and joined to the connection hole 152 of the power supply board 150, and a motor connection. It has bent portions 1433 that sandwich and contact the terminal 210 from both sides. The bent portion 1433 is configured to be pinched from both sides with strong force in order to ensure reliable contact with the motor connection terminal 210. Therefore, when the motor connection terminal 210 is attached or removed (inserted or removed), a large frictional force is generated between the motor connection terminal 210 and the bent portion 1433 of the holding member connection terminal 143 in the attachment/detachment direction as shown by the arrow in FIG. The insertion piece 1431 is made strong so as to be able to withstand the load resulting from such frictional force. Similarly, the support groove 147 is made to sufficiently support the load from the insertion piece 1431 resulting from the frictional force generated when the motor connection terminal 210 is inserted and removed.

In this way, the insertion piece 1431 is firmly fixed, with the entire load from the bent portion 1433 that generates friction being supported by the support groove 147. Since the insertion piece 1431 is firmly fixed, the joining piece 1432 that is fitted into and joined to the connection hole 152 of the power supply board 150 does not move or receive any load from the bent portion 1433. Therefore, by forming the support groove 147 in the substrate holding member 140 other than the circuit board to receive the load in the attachment/detachment direction that occurs when the motor connection terminal 210 is inserted into or removed from the holding member connection terminal 143, the bonding that occurs during attachment/detachment is prevented. It is possible to reduce the load applied to the joint between the piece 1432 and the connection hole 152 of the power supply board 150, and to provide an electric power steering device 1 with a detachable electric motor that has high connection reliability.

Further, the joining piece 1432 located at one end of the holding member connection terminal 143 is joined to the power supply board 150, and the support groove 147 provided in the board holding member 140 that supports this power supply board 150 is connected to the holding member connection terminal 143. Supports the load applied to the According to this, it is possible to reduce the load applied to the joint (soldering part) between the joint piece 1432 of the holding member connection terminal 143 and the power supply board 150 during assembly. This is because if a terminal to be connected to the motor connection terminal 210 is provided on the power supply board 150, the load generated when the motor connection terminal 210 is attached or detached will be directly applied to the joint between the terminal and the power supply board 150.

<Second example>
The electric power steering device 1A in this embodiment will be described with reference to FIGS. 16 to 18. In order to avoid redundant description, the same components as in the above embodiment will be given the same reference numerals and explanations will be omitted, and the explanation will focus on the points that are different from the above embodiment. The electric power steering device 1A includes a motor housing 200 that accommodates an electric motor MT, a plurality of circuit boards that mount electronic components for controlling the electric motor MT, and a control unit that is detachably attached to the motor housing 200. 100C. The control unit 100C includes a connector assembly 110, a heat sink cover 120, a drive board 130A, a board holding member 140A, a power supply board 150A, and a control board 160 in order from the motor housing 200.

As shown in FIG. 17(C), the drive board 130A includes a drive electronic component 131 such as a bridge circuit, a power supply drive terminal 132 that extends toward the electric motor MT, and is electrically connected to the power supply board 150A. It has a connection terminal 133A that extends toward the electric motor MT and is electrically connected to the holding member connection terminal 143A. The drive board 130A is arranged with the surface on which the drive electronic component 131, the power supply terminal 132, and the connection terminal 133A are mounted facing the board holding member 140A side.

As shown in FIG. 18(B), the power supply board 150A includes a power supply electronic component 151 (not shown because it is mounted on the back side of the board) for generating power for the drive board 130A, and a part of the holding member connection terminal 143A. (joint piece 1432A) and a relief hole 154 provided to avoid interference between the part where the tip of the connection terminal 133A is joined and the power supply board 150. Since the joining piece 1432A of the holding member connecting terminal 143A and the tip of the connecting terminal 133A are joined by welding or soldering, the holding member connecting terminal 143A and the connecting terminal 133A are electrically connected. The power supply board 150A is arranged closer to the electric motor MT than the drive board 130A in the axial direction of the output shaft RT, with the surface on which the power supply electronic component 151 is mounted facing the drive board 130A side. The drive board 130A is held at one end of the board holding member 140A, and the power supply board 150A is held at the other end of the board holding member 140A.

As shown in FIG. 17A, the board holding member 140A includes a holding part 141 that holds the drive board 130A and the power supply board 150A at a predetermined distance, and a holding member connection terminal 143A that is connected to the motor connection terminal 210. , has a terminal holding part 142 that holds the holding member connection terminal 143A, and a press-in cover 146 for protecting the holding member connection terminal 143A. One end (joint piece 1432A) of the holding member connection terminal 143A is electrically connected to the direct connection terminal 133A. In this way, the holding member connection terminal 143A is electrically connected to the connection terminal 133A extending from the drive board 130A, but the load applied to the holding member connection terminal 143A by the board holding member 140A that supports the drive board 130A. By supporting, it is possible to reduce the load applied to the joint between the holding member connection terminal 143A and the connection terminal 133A that occurs during assembly.

It should be noted that the present invention is not limited to the illustrated embodiments, and can be implemented with configurations within a range that does not depart from the content described in each section of the claims. That is, although the present invention has been particularly illustrated and described primarily with respect to particular embodiments, there may be other modifications to the embodiments described above without departing from the spirit and scope of the invention. Various modifications can be made by those skilled in the art in other detailed configurations.

For example, in the electric power steering device 1 of the above embodiment, the electric motor and the control unit each have two redundant systems, but they may not be redundant, and the number of redundant systems may be three or more. Good too. Furthermore, although the control unit of the above embodiment has a configuration including three circuit boards: a drive board, a power supply board, and a control board, for example, as the degree of integration of components mounted on the circuit board increases, two circuit boards are required. It is also possible to have a configuration. The present invention only needs to include at least two circuit boards with the board holding member sandwiched therebetween.

1 Electric power steering control device (motor control device)
10A/B 1st system/2nd system 100 (100A/B) Control unit (1st control system/2nd control system)
110 Connector assembly 111 Connector 112 Power supply terminal 113 Control terminal 120 Heat sink cover 130 Drive board 131 Drive electronic component 132 Power drive terminal 133 Connection terminal 140 Board holding member 141 Holding part (board holding part)
142 Terminal holding part 143 Holding member connection terminal (second terminal)
1431 Insertion piece 1432 Joint piece 1433 Bent part 144 Holding member fixing part 145 Guide hole 146 Press-in cover 147 Support groove (load support part)
150 Power supply board 151 Power supply electronic component 152 Connection hole 153 Connection terminal hole 154 Escape hole 160 Control board 161 Rotation sensor (MR sensor)
162 Control unit (microcomputer)
200 Motor housing 210 Motor connection terminal (first terminal)
MTA 1st electric motor MTB 2nd electric motor RT Output shaft of electric motor

Claims (4)

A motor control device comprising: a motor housing that accommodates an electric motor; and a control unit that is detachably attached to the motor housing and has a circuit board that mounts electronic components for controlling the electric motor;
the motor housing includes a first terminal electrically connected to the electric motor and extending toward the control unit;
The control unit includes:
a second terminal connected to the first terminal when attached;
a board holding member having a board holding part that holds at least two circuit boards facing each other in the attachment/detachment direction and a terminal holding part that holds the second terminal;
Equipped with
The terminal holding portion is provided on the outer periphery of the board holding member between the at least two circuit boards in the attachment/detachment direction,
The terminal holding portion is formed in a direction perpendicular to both an attachment/detachment direction and a direction orthogonal to the attachment/detachment direction to support a load in the attachment/detachment direction that occurs when the first terminal is inserted into or removed from the second terminal. a support groove is formed to support the second terminal from both sides ;
the second terminal has an insertion piece inserted into the support groove;
Motor control device. The at least two circuit boards are a first circuit board held at one end of the board holding member, and a first circuit board held at the other end of the board holding member, and arranged closer to the electric motor than the first circuit board. a second circuit board;
The second circuit board has a connection hole with the second terminal,
The motor control device according to claim 1, wherein one end of the second terminal passes through the connection hole and is joined. The at least two circuit boards are a first circuit board held at one end of the board holding member, and a first circuit board held at the other end of the board holding member, and arranged closer to the electric motor than the first circuit board. a second circuit board;
The first circuit board has a terminal for connection to the second terminal extending toward the electric motor,
The motor control device according to claim 1, wherein one end of the second terminal is joined to the connection terminal. 4. The motor control device according to claim 1, wherein the electric motor is used for electric power steering mounted on a vehicle.