JP7182486B2 - electric drive - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric drive device, and more particularly to an electric drive device incorporating an electronic control device.

In the field of general industrial machinery, electric motors are used to drive mechanical control elements. A so-called electromechanical integrated type electric drive device, which is integrally incorporated into a motor, is beginning to be adopted.

As an example of an electromechanically integrated electric drive device, for example, in an electric power steering device for an automobile, the steering wheel is operated by the driver to detect the rotation direction and the rotation torque of the rotating steering shaft. Based on this detected value, the electric motor is driven to rotate in the same direction as the steering shaft, thereby generating steering assist torque. In order to control the electric motor, an electronic control unit (ECU) is provided in the power steering device.

As a conventional electric power steering device, for example, one described in Japanese Patent Application Laid-Open No. 2018-125948 (Patent Document 1) is known. Japanese Patent Application Laid-Open No. 2002-200001 describes an electric power steering device that is composed of an electric motor section and an electronic control section.

In addition, as an electric drive device integrated with an electronic control device, an electric brake, an electrohydraulic controller for controlling various hydraulic pressures, and the like are known. explain.

JP 2018-125948 A

In the electric power steering apparatus disclosed in Patent Document 1, the control circuit board and the power circuit board are laminated and arranged, and these circuit boards are separately fixed to the end wall of the motor housing by fixing bolts. there is

In Patent Document 1, the power circuit board is arranged closer to the end wall side of the motor housing than the control circuit board, but the control circuit board is arranged closer to the end wall side of the motor housing than the power circuit board. The same is true if there is

In this way, the control circuit board and the power circuit board are stacked and arranged, and fixed to the respective fixing bosses with the fixing bolts. There is a problem that the mounting area for fixing the substrate becomes large, and the mounting area for the electronic and electric parts decreases.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a novel electric drive apparatus which can expand the mounting area of electronic components and electric components of the circuit board located on the end face wall side of the motor housing, with the circuit boards arranged in layers. That's what it is.

The present invention
A motor housing containing an electric motor that drives a mechanical system control element, and a circuit component that is arranged on the side of the end wall of the motor housing that is opposite to the output section of the rotating shaft of the electric motor and that drives the electric motor. at least two first and second circuit boards mounted with, a spacer of a predetermined length interposed between each circuit board, and a connector assembly connected to each circuit board,
arranging a first circuit board, a spacer, a second circuit board, and a connector assembly in this order from the end wall of the motor housing in the axial direction of the rotating shaft of the electric motor;
The shared fixing member is fixed to the end wall of the motor housing from the connector assembly side by passing through the connector assembly, the second circuit board, the spacer, and the through holes provided in the first circuit board. is characterized by

In addition, the present invention
A motor housing containing an electric motor that drives a mechanical system control element, and a circuit component that is arranged on the side of the end wall of the motor housing that is opposite to the output section of the rotating shaft of the electric motor and that drives the electric motor. a first spacer having a predetermined length interposed between the first circuit board and the second circuit board; a second spacer having a predetermined length interposed between the second circuit board and the third circuit board and fixed to the end wall; and a connector assembly connected to each circuit board,
The order of the third circuit board, the second spacer, the second circuit board, the first spacer, the first circuit board, and the connector assembly from the end wall of the motor housing in the axial direction of the rotating shaft of the electric motor. and place them in the
A shared fixing member is inserted from the connector assembly side through through holes provided in the connector assembly, the first circuit board, the first spacer, and the second circuit board, and is fixed to the second spacer. It is characterized by

According to the present invention, it is possible to increase the mounting area of the electronic components and electrical components of the circuit board located on the end wall side of the motor housing among the circuit boards arranged in a stack.

1 is an overall perspective view of a steering device; FIG. 1 is an overall perspective view of an electric power steering device to which the present invention is applied; FIG. 1 is an exploded perspective view of an electric power steering apparatus according to a first embodiment of the invention; FIG. FIG. 4 is a side view of the electronic control unit from which the cap cover is removed from the electric power steering device shown in FIG. 3; FIG. 5 is a perspective view of the electronic control unit of FIG. 4 as seen obliquely from above; It is a sectional view showing a modification of a spacer. FIG. 11 is a side view of the electronic control unit from which the cap cover is removed from the electric power steering apparatus according to the second embodiment of the present invention; FIG. 8 is a cross-sectional view of the electronic control unit of FIG. 7 taken in a direction in which a shared fixing bolt extends; FIG. 8 is a perspective view of the electronic control unit of FIG. 7 as seen obliquely from above;

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments, and various modifications and applications can be made within the technical concept of the present invention. is also included in the scope.

Before describing the embodiments of the present invention, the configuration of a steering system as an example to which the present invention is applied will be briefly described with reference to FIG.

First, a steering device for steering the front wheels of an automobile will be described. The steering system 1 is constructed as shown in FIG. A pinion (not shown) is provided at the lower end of a steering shaft 2 connected to a steering wheel (not shown), and this pinion meshes with a rack (not shown) elongated in the lateral direction of the vehicle body.

Tie rods 3 for steering the front wheels in the left-right direction are connected to both ends of the rack, and the rack is covered with a rack housing 4 . A rubber boot 5 is provided between the rack housing 4 and the tie rod 3 .

An electric power steering device 6 is provided to assist the torque when turning the steering wheel. That is, a torque sensor 7 is provided for detecting the rotation direction and rotation torque of the steering shaft 2, and an electric motor unit 8 for applying a steering assist force to the rack via a gear 10 based on the detected value of the torque sensor 7. and an electronic control section 9 for controlling the electric motor arranged in the electric motor section 8 .

The electric motor portion 8 of the electric power steering device 6 is connected to the gear 10 via bolts (not shown) at three points on the outer periphery on the output shaft side, and the electronic control portion 9 is provided on the side opposite to the output shaft of the electric motor 8 portion. is provided.

In the electric power steering device 6, when the steering shaft 2 is rotated in one direction by operating the steering wheel, the torque sensor 7 detects the rotation direction and the rotation torque of the steering shaft 2. Based on this detected value, the control circuit section of the electronic control section 9 calculates the drive operation amount of the electric motor.

Based on the calculated drive operation amount, the electric motor is driven by the power switching element of the power conversion circuit unit of the electronic control unit 9, and the output shaft of the electric motor is rotated in the same direction as the operation direction of the steering shaft 2. driven by Rotation of the output shaft is transmitted from a pinion (not shown) to a rack (not shown) via a gear 10 to steer the automobile. Since these configurations and actions are already well known, further explanation will be omitted.

By the way, recent electric power steering devices and the like are required to be compatible with cyber security and OTA (Over The Air). Further, in order to cope with cyber security and OTA, additional electronic components are required, and it is expected that the number of electronic components will increase. On the other hand, electric power steering devices are also required to be downsized. Therefore, in order to satisfy these demands, it is necessary to expand the mounting area of the circuit board on which the electronic parts and electric parts are mounted in the electronic control unit.

In Patent Document 1, when a control circuit board and a power supply circuit board are stacked and arranged and fixed to a fixed boss by a fixing bolt, the circuit board arranged close to the end wall side of the motor housing is used for other circuits. The mounting area for the electronic and electrical components is reduced by the amount of the notched portion corresponding to the fixing boss of the substrate. Similarly, a head-receiving area for receiving the head of the fixing bolt is required, which also reduces the mounting area for electronic and electrical parts. Therefore, it is demanded to increase the mounting area of the electronic components and electric components of the circuit boards which are arranged in layers and which are arranged closer to the end wall side of the motor housing.

Against this background, the present embodiment proposes an electric power steering apparatus having the following configuration.

In the present embodiment, at least two first and second plates are arranged on the side of the end wall of the motor housing opposite to the output portion of the rotating shaft of the electric motor, and are mounted with circuit components for driving the electric motor. 2 circuit boards, spacers of a predetermined length interposed between the respective circuit boards, and connector assemblies connected to the circuit boards, respectively, and are mounted on the motor housing in the axial direction of the rotating shaft of the electric motor. The first circuit board, the spacer, the second circuit board, and the connector assembly are arranged in this order from the end wall, and the shared fixing member is arranged from the connector assembly side, the connector assembly, the second circuit. The substrate, the spacer, and the through hole provided in the first circuit board are inserted and fixed to the end wall of the motor housing.

According to such a configuration, the first circuit board, the spacer, the second circuit board, and the connector assembly are arranged in order in the axial direction of the rotating shaft of the electric motor in the direction away from the end wall of the motor housing. and the shared fixing member is inserted from the connector assembly side through the through holes provided in the connector assembly, the second circuit board, the spacer, and the first circuit board, and fixed to the end wall of the motor housing. Therefore, it is possible to increase the mounting area of the electronic components and electrical components of the circuit boards located on the end wall side of the motor housing among the circuit boards arranged in a stack.

A specific configuration of an electric power steering apparatus according to an embodiment of the present invention will be described in detail below with reference to FIGS. 2 to 5. FIG. FIG. 2 is a drawing showing the overall configuration of the electric power steering device according to the present embodiment, and FIG. 3 is an exploded view of the components of the electric power steering device shown in FIG. 4 is a side view of the electronic control unit with the cap cover removed, and FIG. 5 is an oblique top view of the electronic control unit in FIG.

As shown in FIG. 2, the electric motor section 8 constituting the electric power steering device 6 is composed of a motor housing 11 having a cylindrical section made of aluminum alloy or the like, and an electric motor (not shown) accommodated therein. , The electronic control unit consists of a cap cover 12 made of aluminum alloy or the like, which is arranged on the opposite side of the motor housing 11 from the output shaft 14 in the axial direction, and an electronic control unit 9 (not shown) housed therein. It is

The motor housing 11 and the cap cover 12 are integrally fixed at their opposing end surfaces by adhesive, welding, or fixing bolts. The electronic control unit 9 housed in the housing space inside the cap cover 12 includes a power circuit unit for generating necessary power, and a power switching element such as a MOSFET or an IGBT for driving and controlling the electric motor of the electric motor unit 8. and a control circuit for controlling the power switching element, and the output terminal of the power switching element and the coil input terminal of the electric motor are electrically connected via a bus bar.

A connector assembly 13 is provided on the end surface of the cap cover 12 . The connector assembly 13 includes a connector terminal forming portion 13A for power supply, a connector terminal forming portion 13B for a detection sensor, and a connector terminal forming portion 13C for sending out a control state to an external device.

The electronic control unit 9 housed in the cap cover 12 is supplied with electric power from a power supply through a connector terminal forming unit 13A for power supply made of synthetic resin, and detects the operating state and the like from detection sensors. A signal is supplied through a connector forming terminal portion 13B for a detection sensor, and a current control state signal of the electric power steering apparatus is sent out through a connector terminal forming portion 13C for sending control state.

FIG. 3 shows an exploded perspective view of the electric power steering device 6. As shown in FIG. An annular iron side yoke (not shown) is fitted inside the motor housing 11, and an electric motor (not shown) is accommodated in this side yoke. An output portion 14 of the electric motor applies a steering assist force to the rack through a gear. Since the specific structure of the electric motor is well known, the explanation is omitted here.

The motor housing 11 is made of an aluminum alloy, and functions as a heat sink member that releases heat generated by the electric motor and heat generated by a power supply circuit section and a power conversion circuit section described later to the outside atmosphere. An electric motor section 8 is composed of the electric motor and the motor housing 11 .

An end wall 15 of the motor housing 11 is formed on the opposite side of the output portion 14 of the electric motor portion 8, and the electronic control portion 9 is attached to the end wall 15. As shown in FIG. The electronic control unit 9 is composed of a power conversion circuit unit 16 , a power supply circuit unit 17 and a control circuit unit 18 . The end wall 15 of the motor housing 11 functions as a heat sink and is integrally formed with the motor housing 11. Alternatively, only the end wall 15 is formed separately and integrated with the motor housing 11 by bolts or welding. It is a good thing.

Here, the power conversion circuit section 16, the power supply circuit section 17, and the control circuit section 18 constitute a redundant system, and constitute a dual system of the main electronic control section and the sub electronic control section. The electric motor is normally controlled and driven by the main electronic control section, but if an abnormality or failure occurs in the main electronic control section, it is switched to the sub electronic control section to control and drive the electric motor.

Therefore, normally, the heat from the main electronic control section is transferred to the motor housing 11, and when an abnormality or failure occurs in the main electronic control section, the main electronic control section stops, the sub electronic control section operates, and the motor housing 11 The heat from the sub electronic control unit is transmitted to.

Separately from this, the main electronic control unit and the sub electronic control unit are combined to function as a regular electronic control unit, and if an abnormality or failure occurs in one electronic control unit, more than half of the other electronic control unit will It is also possible to control and drive an electric motor by ability.

In this case, the performance of the electric motor is reduced, but the so-called "power steering function" is ensured. Therefore, in a normal case, heat from the main electronic control section and the sub electronic control section is transferred to the motor housing 11 .

The electronic control unit 9 is composed of a control circuit unit 18, a power supply circuit unit 17, a power conversion circuit unit 16, and a connector assembly 13. The power conversion circuit unit 16, the power supply circuit unit 17, the control circuit unit 18, and the connector assembly 13 are arranged in this order.

Here, the axis of the motor housing means an axis that substantially coincides with the centerline of the rotating shaft of the electric motor housed in the motor housing 11. Hereinafter, the axis of the motor housing is simply referred to as the axis. In some cases.

The control circuit section 18 generates control signals for driving the power switching elements of the power conversion circuit section 16, and is composed of a microcomputer, peripheral circuits, and the like. The power supply circuit section 17 generates a power supply for the control circuit section 18 and a power supply for the power conversion circuit section 16, and is composed of a capacitor, a coil, a power switching element, and the like. The power conversion circuit unit 16 adjusts the power flowing through the coils of the electric motor, and is composed of power switching elements and the like that form three-phase upper and lower arms.

Circuit parts such as electric parts and electronic parts constituting the control circuit section 18 and the power supply circuit section 17 are mounted on the surface of a circuit board made of a glass epoxy board. are arranged in a radial direction perpendicular to the The control circuit section 18, the power supply circuit section 17, and the power conversion circuit section 16 are arranged in a form of being sequentially laminated in the axial direction.

In the electronic control unit 9, the power conversion circuit unit 16 and the power supply circuit unit 17 mainly generate a large amount of heat, and the heat of the power conversion circuit unit 16 and the power supply circuit unit 17 is released from the motor housing 11 made of aluminum alloy be done. In addition, in this embodiment, the power conversion circuit unit 16 is attached to the end wall 15 of the motor housing 11 in close contact therewith.

The power conversion circuit unit 16 is attached in close contact with the end wall 15 by means of a fixing member 20 having an elastic function. That is, the elastic function member formed in the fixing member 20 presses the power conversion circuit portion 16 toward the heat dissipation portion side formed on the end wall 15 side of the motor housing 11, and the power conversion circuit portion 16 becomes the heat dissipation portion. pressed and held.

A connector assembly 13 made of synthetic resin is disposed between the control circuit portion 18 and the cap cover 12, and is connected to a vehicle battery (power supply) and other external control devices (not shown). Needless to say, the connector assembly 13 is appropriately connected to the power conversion circuit section 16, the power supply circuit section 17, and the control circuit section .

The cap cover 12 has a function of housing the power conversion circuit section 16, the power supply circuit section 17, and the control circuit section 18 and sealing them in a liquid-tight manner. It is fixed to the end wall 15 of the motor housing 11 . Since the cap cover 12 is made of metal, it also has a function of dissipating heat generated by the power conversion circuit section 16, the power supply circuit section 17, etc. to the outside.

An opening 12A is formed in the cap cover 12, and connector terminal forming portions 13A to 13C of the connector assembly 13 are exposed through the opening 12A. The opening 12A is closely attached to the connector assembly 13, and an O-ring or a liquid sealing agent is arranged in this close contact portion for liquid tightness.

Heat radiation areas 15A and 15B of the power conversion circuit section 16 and the power supply circuit section 17 are formed on the surface of the end wall 15 located on the side opposite to the output section 14 of the electric motor. Board fixing portions 21A and 21B having the same height are integrally formed at the four corners of the end wall 15, and bolt screw holes 21S are formed therein. The board fixing portions 21A and 21B are provided for mounting a power circuit board (corresponding to a first circuit board) 17Bs of the power circuit section 17 .

Here, the substrate fixing portion 21A is formed upright from the power conversion heat dissipation region 15A, and the substrate fixing portion 21B is formed in the power heat dissipation region 15B. The board fixing portion 21B formed in the power heat radiation region 15B is the board fixing portion 21B including the power heat radiation region 15B.

As can be seen from FIG. 3, the plane area forming the radial end wall 15 perpendicular to the axis is divided into two. One forms a power conversion heat radiation area 15A to which the power conversion circuit section 16 is attached, and the other forms a power supply heat radiation area 15B to which the power supply circuit section 17 is attached. In this embodiment, the area of the power conversion heat dissipation region 15A is formed to be larger than that of the power supply heat dissipation region 15B. This is to secure the installation area of the power conversion circuit unit 16 since the duplex system is adopted as described above.

The power conversion heat radiation area 15A and the power heat radiation area 15B have steps with different heights in the axial direction. That is, the power-supply heat-radiating region 15B is formed to have steps in the direction away from the power conversion heat-radiating region 15A when viewed in the axial direction. This step is set to a length such that the power inverter circuit unit 16 and the power supply circuit unit 17 do not interfere with each other when the power supply circuit unit 17 is installed after the power inverter circuit unit 16 is installed.

Three elongated rectangular projecting heat radiation portions 22 are formed in the power conversion heat radiation region 15A. A double-system power conversion circuit unit 16 is installed in the projecting heat radiation unit 22 . The projecting heat radiating portion 22 protrudes and extends in a direction away from the electric motor when viewed in the axial direction.

Further, the power heat radiation area 15B is planar, and the power circuit board 17Bs of the power circuit section 17 is installed thereon. Further, an extended heat radiation area 15C extending toward the center of the rotation shaft of the electric motor is formed in the power heat radiation area 15B. This is because when the three power conversion circuit units 16 are placed on the protruding heat dissipation unit 22 in a U-shape, the space where the power conversion circuit units 16 do not exist is used as a heat dissipation area for the power supply circuit unit 17. is formed to

Therefore, the projecting heat radiation portion 22 functions as a heat radiation portion that transfers the heat generated in the power conversion circuit portion 16 to the end wall 15 , and the heat radiation region 15 B for power supply transmits the heat generated in the power supply circuit portion 17 to the end wall 15 . It functions as a heat-dissipating part that transfers heat. Note that the projecting heat radiation portion 22 can be omitted, and in this case, the power conversion heat radiation region 15A functions as a heat radiation portion that transfers heat generated in the power conversion circuit portion 16 to the end wall 15 .

As described above, in the end wall 15 of the motor housing 11 according to the present embodiment, the heat sink member can be omitted, so that the length in the axial direction can be shortened. Further, since the motor housing 11 has a sufficient heat capacity, the heat of the power supply circuit section 17 and the power conversion circuit section 16 can be efficiently radiated to the outside.

Next, the power supply circuit section 17 is installed from above the power conversion circuit section 16. In this case, the power supply circuit board 17Bs of the power supply circuit section 17 is installed above the power supply heat radiation area 15B. Capacitors, coils, and the like that constitute the power supply circuit section 17 are mounted on a power supply circuit board 17Bs made of a glass epoxy board. The power supply circuit section 17 also employs a duplex system, and as can be seen from the drawing, the power supply circuits are formed in line-symmetrical form, each comprising a capacitor, a coil, and the like.

The surface of the power circuit board 17Bs on the side of the power heat radiation area 15B is fixed to the end wall 15 so as to be in contact with the power heat radiation area 15B. The fixing method is to screw an elongated "shared fixing bolt" (which will be described later) that functions as a "shared fixing member" into the bolt screw holes 21S provided in the board fixing parts 21A and 21B. . Accordingly, through holes 17H corresponding to the positions of the bolt screw holes 21S of the board fixing portions 21A and 21B are formed at the four corners of the power supply circuit board 17Bs.

Here, the power supply circuit board 17Bs is fixed by a common fixing bolt, which will be described later, and does not have a notch that matches the shape of the fixing boss that fixes the control circuit board, as in Patent Document 1. Similarly, there is no head-receiving area for a fixing bolt to be screwed into the fixing boss in order to fix the power circuit board to the fixing boss. Therefore, it is possible to expand the mounting area of the electronic components and electrical components of the power supply circuit board 17Bs located on the side of the end wall 15 of the motor housing.

Since the power supply circuit board 17Bs of the power supply circuit section 17 is formed of a glass epoxy board, double-sided mounting is possible. On the surface of the power supply circuit board 17Bs facing the heat dissipation area 15B for the power supply, a rotation phase and rotation speed detection unit including a GMR element (not shown) and a detection circuit for the same is mounted. In cooperation with the detection section, the rotation phase and rotation speed of the rotating shaft are detected.

Since the power circuit board 17Bs is fixed so as to be in thermal contact with the power heat radiation area 15B, the heat generated in the power circuit section 17 can be efficiently transferred to the power heat radiation area 15B. The heat transferred to the power-use heat dissipation area 15B is also diffused and transferred to the side peripheral surface portion 11A of the motor housing 11, and is radiated to the outside.

Here, between the power supply circuit board 17Bs and the power supply heat dissipation area 15B, any one of an adhesive having good heat transfer properties, heat dissipation grease, heat dissipation sheet, etc. is interposed to further improve the heat transfer performance. can be done.

Next, the control circuit 18 is installed from the upper side of the power supply circuit section 17. The microcomputer and peripheral circuits constituting the control circuit section 18 are mounted on a control circuit board (corresponding to a second circuit board) made of a glass epoxy board. It is implemented in 18Bs. The control circuit section 18 also employs a dual system, and as can be seen from the figure, the control circuits each comprising a microcomputer, peripheral circuits, etc. are formed in a line-symmetrical manner. The microcomputer, peripheral circuits, and the like may be provided on the surface of the control circuit board 18Bs on the power supply circuit 17 side.

In this manner, the control circuit section 18 is installed in a laminated form on the upper portion of the power supply circuit section 17. The power supply circuit board 17Bs of the power supply circuit section 17 and the control circuit board 18Bs of the control circuit section 18 The space is electrically connected by a flexible substrate 23 . Accordingly, control signals and power supply are exchanged via the flexible substrate 23 . The power supply circuit board 17 and the control circuit board 18 may be connected using a board connector.

Further, a spacer 24 having a predetermined length is interposed between the power circuit board 17Bs and the control circuit board 18Bs. That is, the power circuit board 17Bs and the control circuit board 18Bs are stacked in the axial direction of the motor housing 11, and tall electrical components such as coils and capacitors are mounted on the power circuit board 17Bs.

For this reason, the spacer 24 forms a storage space for storing electrical components such as coils and capacitors. The spacers 24 can be made of synthetic resin or metal, and three or more spacers 24 can form a storage space. In this embodiment, four spacers 24 are used.

The spacer 24 has an annular (pipe-like) shape with both ends opened, and has a through hole 24H formed therein through which the shaft portion of the common fixing bolt passes. Therefore, the spacer 24 is arranged at a position corresponding to the through hole 17H of the power circuit board 17Bs. Furthermore, the diameter of the through hole 24H of the spacer 24 is formed larger than the diameter of the through hole 17H of the power supply circuit board 17Bs and the diameter of the through hole 18H of the control circuit board 18Bs, which will be described later, so that common fixing bolts can easily pass through. .

Through holes 18H corresponding to the positions of the bolt screw holes 21S formed in the board fixing portions 21A and 21B are formed in the four corners of the control circuit board 18Bs. Therefore, in a state in which the power circuit board 17Bs and the control circuit board 18Bs are assembled and stacked, the through hole 18H of the control circuit board 18Bs, the through hole 24H of the spacer 24, the through hole 17H of the power circuit board 17Bs, the board fixing portion 21A, Each of the bolt screw holes 21S of 21B are in a state of overlapping in the axial direction.

Here, the spacers 24 are drawn separately from the power supply circuit board 17Bs and the control circuit board 18Bs, but they can be fixed in advance to the power supply circuit board 17Bs or the control circuit board 18Bs. For example, the spacers 24 can be soldered at the same time as the electronic components and electrical components are soldered to the power circuit board 17Bs or the control circuit board 18Bs by a reflow process. Similarly, it is also possible to adopt a configuration in which they are fixed in advance to the power supply circuit board 17Bs and the control circuit board 18Bs.

Next, the connector assembly 13 is stacked from the upper side of the control circuit section 18 . The connector assembly 13 is formed with a bolt holding portion 13F extending toward the outer peripheral side in a radial direction orthogonal to the axial direction. Through holes 13H corresponding to the positions of the bolt screw holes 21S formed in the substrate fixing portions 21A and 21B are formed at the four corners of the bolt holding portion 13F.

Therefore, when the power supply circuit board 17Bs, the control circuit board 18Bs, and the connector assembly 13 are assembled and stacked, the power supply circuit board is arranged in the axial direction of the motor housing 11 in the direction away from the end wall 15 of the motor housing 11. 17Bs, spacer 24, control circuit board 18Bs, and connector assembly 13 are arranged in this order.

The through holes 13H of the connector assembly 1, the through holes 18H of the control circuit board 18Bs, the through holes 24H of the spacers 24, the through holes 17H of the power supply circuit board 17Bs, and the bolt screw holes 21S of the board fixing portions 21A and 21B are respectively provided. are overlapped in the axial direction.

In this state, from the connector assembly 13 side, the tip of the elongated shared fixing bolt (fixing member) 25 is inserted into the through hole 13H of the bolt holding portion 13F, and the through hole 18H of the control circuit board 18Bs and the spacer 24 are inserted. The common fixing bolt 25 is inserted in the order of the through hole 24H and the through hole 17H of the power supply circuit board 17Bs, and finally the threaded portion of the tip of the common fixing bolt 25 is inserted into the bolt screw hole 21S of the board fixing portions 21A and 21B. Secure by screwing. Therefore, the connector assembly 13 presses the control circuit board 18Bs toward the spacer 24 side, and the spacer 24 presses and fixes the power supply circuit board 17Bs toward the board fixing portions 21A and 21B.

Further, after this, the open end of the cap cover 12 is engaged with the end face wall 15 of the motor housing 11 and fixed to each other by welding or adhesion.

In this way, it is the shared fixing bolt that fixes the power supply circuit board, and there is no notch that matches the shape of the fixing boss that fixes the control circuit board, as in Patent Document 1. Similarly, there is no head receiving area for a fixing bolt screwed into a fixing boss for fixing the power circuit board to the fixing boss. Therefore, it is possible to increase the mounting area of the electronic components and electrical components of the power supply circuit board located on the end wall side of the motor housing.

Furthermore, in Patent Document 1, the control circuit board and the power circuit board are separately fixed to the fixed boss of the motor housing by fixing bolts, so eight fixing bolts are required, but in this embodiment, Since only four fixing bolts are required, the parts cost of the product can be reduced, and furthermore, since the screwing work for the fixing bolts can be reduced, the manufacturing cost can also be reduced.

Next, the configuration of the assembled electronic control unit 9 will be described with reference to FIGS. 4 and 5. FIG. A power conversion circuit unit 16 is fixed to the end wall 15 of the motor housing 11 in such a manner as to be in close contact therewith. Further, the power supply circuit board 17Bs is mounted on the board fixing portions 21A and 21B on the upper side. Further, electric parts and electronic parts are mounted on the power supply circuit board 17Bs.

Since the coil 26 and the capacitor 27, which are electric parts, are tall (height in the axial direction), a space for accommodating them is required. Therefore, a spacer 24 is soldered onto the through hole 17H of the power circuit board 17Bs by a reflow process. As a matter of course, the through hole 17H of the power supply circuit board 17Bs and the through hole 24H of the spacer 24 are fixed so as to overlap each other.

Furthermore, a control circuit board 18Bs is arranged above the electric parts and electronic parts of the power supply circuit board 17Bs, and the control circuit board 18Bs is supported by spacers 24 . The through hole 18H of the control circuit board 18Bs and the through hole 24H of the spacer 24 are also fixed so as to overlap each other. The control circuit board 18Bs is mounted with electronic and electric parts such as the microcomputer 28 and its peripheral circuits.

Furthermore, the connector assembly 13 is arranged above the electronic and electrical parts of the control circuit board 18Bs. A bolt holding portion 13F is formed in the connector assembly 13, and the bolt holding portion 13F is placed on the upper side of the control circuit board 18Bs. The bolt holding portion 13F is formed with a head housing portion 13C for housing the head portion of the common fixing bolt 25, and the common fixing bolt 25 is inserted from a through hole 13H formed in the bolt holding portion 13F.

The shaft portion 25R of the shared fixing bolt 25 is inserted through the through hole 18H of the control circuit board 18Bs, the through hole 24H of the spacer 24, and the through hole 17H of the power circuit board 17Bs in this order, and finally reaches the tip of the shaft portion 25R. The screw portions are screwed into the bolt screw holes 21S of the board fixing portions 21A and 21B and fixed.

As a result, the control circuit board 18Bs, the spacer 24, and the power circuit board 17Bs are sandwiched from both ends between the bolt holding portion 13F and the board fixing portions 21A and 21B of the connector assembly 13 and firmly fixed.

In this way, it is the shared fixing bolt 25 that fixes the power circuit board 17Bs, and there is no need to form a notch that matches the shape of the fixing boss that fixes the control circuit board 17Bs. Similarly, there is no need to form a head receiving region for a fixing bolt screwed into a fixing boss for fixing the power circuit board 17Bs. Therefore, it is possible to expand the mounting area of the electronic components and electrical components of the power supply circuit board 17Bs located on the side of the end wall 15 of the motor housing.

Furthermore, in this embodiment, only four fixing bolts are required, so that the parts cost of the product can be reduced. Furthermore, since the screwing work of the fixing bolts can be reduced, the manufacturing cost can also be reduced.

Next, a modified example of the spacer 24 will be described with reference to FIG. 6, the spacer 24 is divided into a first divided spacer and a second divided spacer. The first divided spacer is a right cylindrical spacer main body 24C having a through hole 24H, and the second divided spacer is a spacer receiving portion 24R having an accommodation recess 24P in which one end of the spacer 24C is accommodated. Of course, the spacer receiving portion 24R is also provided with a through hole 24H.

The spacer body 24C is fixed by soldering to the control circuit board 18Bs by a reflow process so as to overlap the through hole 18H of the control circuit board 18Bs, and the spacer receiving portion 24R is attached to the power circuit board 17Bs so as to overlap the through hole 17H. 17Bs is soldered by a reflow process. The spacer main body 24C and the spacer receiving portion 24R can also be fixed to opposite circuit boards.

One end of the right cylindrical spacer main body 24C and the housing recess 24P are shaped so that they can be engaged with each other. It is considered to be a shape that can be

Here, the spigot engagement means that a member having a hole having a large diameter is inserted into a member having a smaller diameter to fit and engage the member.

Therefore, it is possible to improve the positional alignment of the through-hole 24H of the spacer 24, the through-hole 17H of the power supply circuit board 17Bs, and the through-hole 18H of the control circuit board 18Bs, and further improve the ease of assembly.

Next, a second embodiment of the invention will be described. In the first embodiment, the power conversion circuit unit 16 is directly attached to the power conversion heat dissipation area 15A formed on the end wall 15 of the motor housing 11. It differs in that power switching elements and the like are mounted.

For this reason, a second spacer is newly provided to form a storage space for the power switching element of the power conversion circuit board and to fix the power conversion circuit board to the end surface portion. In accordance with this, in this embodiment, the space 24 of the first embodiment will be described as a "first spacer 24".

In the present embodiment, at least three first and third polarizers mounted with circuit components for driving the electric motor are arranged on the side of the end wall of the motor housing opposite to the output portion of the rotary shaft of the electric motor. 2, and a third circuit board, a first spacer having a predetermined length interposed between the first circuit board and the second circuit board, and a spacer between the second circuit board and the third circuit board. A second spacer of predetermined length interposed therebetween and secured to the end wall, and a connector assembly connected to the respective circuit board, extending axially away from the end wall of the motor housing. the third circuit board, the second spacer, the second circuit board, the first spacer, the first circuit board, and the connector assembly in this order, and the common fixing member is the connector From the assembly side, the connector assembly, the first circuit board, the first spacer, and the through holes provided in the second circuit board are inserted and fixed to the second spacer.

According to such a configuration, the third circuit board, the second spacer, the second circuit board, the first spacer, the second One circuit board and the connector assembly are arranged in this order, and common fixing members are provided on the connector assembly, the first circuit board, the first spacer and the second circuit board from the connector assembly side. are inserted through the through-holes and fixed to the second spacer, the mounting area of the electronic components and electrical components of the circuit board located on the end face wall side of the motor housing among the circuit boards arranged in layers is small. can be expanded.

The second embodiment will be described below, but since the same reference numbers as in the first embodiment indicate the same constituent elements, the description will be omitted.

7 to 9, a power conversion circuit board (third circuit board) 16Bs made of a glass epoxy board is mounted with a power switching element 29 made of a MOSFET or an IGBT. The power switching element 29 is arranged on the power supply circuit board 17Bs side of the power conversion circuit board 16Bs, but it can also be arranged on the opposite side. In this case, a storage space for the power switching element 29 may be provided in part of the end wall 15 .

The power conversion circuit board 16Bs is arranged between the power supply circuit board 17Bs and the end wall 15 of the motor housing 11 with a second spacer 30 interposed therebetween. The second spacer 30 has a length that can form a storage space for storing the power switching element 29 and its related components, or the electrical and electronic components mounted on the power conversion circuit board 16Bs side of the power supply circuit board 17Bs. It is decided.

As shown in FIG. 8, the second spacer 30 is driven into a threaded portion 30S into which the threaded portion at the tip of the common fixing bolt 25 is screwed, and into a fitting fixing hole 31 formed in the end wall 15, and is driven into the fixing hole. 31, and a fitting fixing portion 30F that fits into the fitting portion 30F. The positions where the fitting fixing holes 31 are formed are positions equivalent to the positions of the bolt screw holes 21S of the board fixing portions 21A and 21B described in the first embodiment. The fitting fixing portion 30F and the fitting fixing hole 31 can be changed to screw fixing.

Between the threaded portion 30S and the fitting and fixing portion 30F, a fixing stepped portion 30N is formed, the diameter of which increases from the fitting and fixing portion 30F to the threaded portion 30S. In a state in which the fitting fixing portion 30F penetrates the through hole 16H formed in the power conversion circuit board 16Bs and is fixed to the fitting fixing hole 31, the fixing step portion 30N moves the power conversion circuit board 16Bs between the end walls 15. It is fixed by sandwiching it with

Therefore, in the state where the power conversion circuit board 16Bs, the power supply circuit board 17Bs, the control circuit board 18Bs, and the connector assembly 13 are assembled and stacked, in the axial direction of the motor housing 11, in the direction away from the end wall 15 of the motor housing 11 The power conversion circuit board 16Bs, the second spacer 30, the power circuit board 17Bs, the first spacer 24, the control circuit board 18Bs, and the connector assembly 13 are arranged in this order.

Then, the shaft portion 25R of the shared fixing bolt 25 is inserted into the through hole 13H of the connector assembly 13, the through hole 18H of the control circuit board 18Bs, the through hole 24H of the first spacer 24, and the through hole 17H of the power supply circuit board 17Bs in this order. Finally, the threaded portion at the tip of the shaft portion 25R is screwed into the threaded portion 30S of the second spacer 30 and fixed.

Therefore, the control circuit board 18Bs is pressed against the first spacer 24 side by the connector assembly 13, and the power supply circuit board 17Bs is pressed against the second spacer 30 side by the first spacer 24 and fixed. As a result, the control circuit board 18Bs, the first spacer 24, and the power circuit board 17Bs are pressed from both ends between the bolt holding portion 13F and the second spacer 30 of the connector assembly 13 and firmly fixed. Also, the power conversion circuit board 16Bs is fixed to the end wall 15 by the second spacer 30 .

It goes without saying that the first spacer 24 may be replaced with the spacer shown in FIG. 6 also in this embodiment.

Thus, in the second embodiment as well, it is the common fixing bolt 25 that fixes the power supply circuit board 17Bs, and it is necessary to form a notch that matches the shape of the fixing boss that fixes the control circuit board 17Bs. Gone. Similarly, there is no need to form a head receiving region for a fixing bolt screwed into a fixing boss for fixing the power circuit board 17Bs. Therefore, it is possible to expand the mounting area of the electronic components and electrical components of the power supply circuit board 17Bs located on the side of the end wall 15 of the motor housing.

Furthermore, in this embodiment, only four fixing bolts are required, so that the parts cost of the product can be reduced. Furthermore, since the screwing work of the fixing bolts can be reduced, the manufacturing cost can also be reduced.

Here, the second spacer 30 can also be formed integrally with the end face portion 15 of the motor housing 11 . However, in this case, the power conversion circuit board 16Bs may be fixed to the end surface portion 15 with another fixing bolt, or may be configured in the same manner as in the first embodiment.

As described above, in the present invention, at least two sheets mounted with circuit components for driving the electric motor are arranged on the side of the end wall of the motor housing opposite to the output portion of the rotary shaft of the electric motor. Equipped with first and second circuit boards, spacers of a predetermined length interposed between the respective circuit boards, and connector assemblies connected to the respective circuit boards, the electric motor is provided in the axial direction of the rotating shaft of the electric motor. From the end wall of the motor housing, the first circuit board, the spacer, the second circuit board, and the connector assembly are arranged in this order, and the common fixing member is arranged from the connector assembly side, the connector assembly, the second The second circuit board, the spacer, and the through hole provided in the first circuit board are inserted into the first circuit board and fixed to the end wall of the motor housing.

Further, in the present invention, at least three first, first, and second motors mounted with circuit components for driving the electric motor are arranged on the side of the end wall of the motor housing opposite to the output portion of the rotating shaft of the electric motor. second and third circuit boards, a first spacer having a predetermined length interposed between the first circuit board and the second circuit board, the second circuit board and the third circuit board A second spacer of a predetermined length interposed between and fixed to the end wall, and a connector assembly connected to each circuit board, extending in the axial direction of the rotating shaft of the electric motor from the end of the motor housing. From the face wall, the third circuit board, the second spacer, the second circuit board, the first spacer, the first circuit board, and the connector assembly are arranged in this order, and the common fixing member is the connector assembly. The connector assembly, the first circuit board, the first spacer, and the through holes provided in the second circuit board are inserted from the side of , and fixed to the second spacer.

According to the present invention, it is possible to increase the mounting area of the electronic components and electrical components of the circuit board located on the end wall side of the motor housing among the circuit boards arranged in a stack.

It should be noted that the present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the described configurations. In addition, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Moreover, it is possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

DESCRIPTION OF SYMBOLS 6... Electric power steering apparatus 8... Electric motor part 9... Electronic control part 11... Motor housing 12... Cap cover 13... Connector assembly 13F... Bolt holding part 13H... Through hole 14... Output part , 15 end wall 16 power conversion circuit unit 17 power supply circuit unit 17Bs power supply circuit board 17H through hole 18 control circuit unit 18Bs control circuit board 18H through hole 21A, 21B Board fixing portion 21S Bolt screw hole 24 Spacer 24H Through hole 25 Common fixing bolt.

Claims (15)

A motor housing housing an electric motor for driving a mechanical system control element, and a motor housing disposed on the side of the end wall of the motor housing opposite to the output portion of the rotating shaft of the electric motor for driving the electric motor. at least two first and second circuit boards on which circuit parts are mounted, a spacer of a predetermined length interposed between each of the circuit boards, and a connector set connected to each of the circuit boards Equipped with three-dimensional
The spacer is divided into a first divided spacer and a second divided spacer, the first divided spacer is fixed to the first circuit board, and the second divided spacer is attached to the second circuit board. is affixed,
The first split spacer and the second split spacer have shapes that are positioned when they are combined,
The first circuit board, the first split spacer, the second split spacer, the second circuit board, and the connector assembly extend from the end wall of the motor housing in the axial direction of the rotating shaft of the electric motor. Arrange these in the order of
A shared fixing member is inserted from the connector assembly side through through holes provided in the connector assembly, the second circuit board, the first split spacer, the second split spacer , and the first circuit board. and fixed to the end wall of the motor housing. In the electric drive device according to claim 1,
The first split spacer is fixed to the first circuit board by soldering, and the second split spacer is fixed to the second circuit board by soldering.
An electric drive device characterized by: In the electric drive device according to claim 2,
The electric drive device according to claim 1, wherein the first split spacer and the first circuit board, and the second split spacer and the second circuit board are soldered by a reflow process. In the electric drive device according to claim 2,
The diameter of the through holes provided in the first split spacer and the second split spacer is larger than the diameter of the through holes provided in the first circuit board and the second circuit board. An electric drive device characterized by: In the electric drive device according to claim 4,
The electric driving device, wherein the first split spacer and the second split spacer are positioned by being engaged with each other. In the electric drive device according to claim 1,
The second circuit board is a control circuit board provided with a control circuit for controlling a power conversion circuit that drives the electric motor,
The first circuit board is a power supply circuit board provided with a power supply circuit that generates power for the power conversion circuit and the control circuit.
An electric drive device characterized by: A motor housing housing an electric motor for driving a mechanical system control element, and a motor housing disposed on the side of the end wall of the motor housing opposite to the output portion of the rotating shaft of the electric motor for driving the electric motor. at least three first, second and third circuit boards on which circuit components are mounted, and a first spacer of a predetermined length interposed between the first circuit board and the second circuit board a second spacer having a predetermined length interposed between the second circuit board and the third circuit board and fixed to the end wall; and a connector assembly connected to each of the circuit boards. with
The third circuit board, the second spacer, the second circuit board, the first spacer, and the first circuit extend from the end wall of the motor housing in the axial direction of the rotating shaft of the electric motor. arranging the substrate and the connector assembly in order,
A shared fixing member is inserted from the connector assembly side through through-holes provided in the connector assembly, the first circuit board, the first spacer, and the second circuit board, and the second circuit board is mounted. fixed to the spacer
An electric drive device characterized by: In the electric drive device according to claim 7,
The first spacer is fixed to the first circuit board or the second circuit board by soldering.
An electric drive device characterized by: In the electric drive device according to claim 8,
The first spacer is soldered to the first circuit board or the second circuit board together with the circuit components by a reflow process.
An electric drive device characterized by: In the electric drive device according to claim 8,
The diameter of the through hole provided in the first spacer is larger than the diameter of the through holes provided in the first circuit board and the second circuit board.
An electric drive device characterized by: In the electric drive device according to claim 7,
The first spacer is divided into a first split spacer and a second split spacer, the first split spacer is fixed to the first circuit board by soldering, and the second split spacer is the second split spacer. It is fixed to the circuit board by soldering, and the first split spacer and the second split spacer have shapes that are positioned when they are combined.
An electric drive device characterized by: In the electric drive device according to claim 7,
The third circuit board is interposed between the second spacer and the end wall.
An electric drive device characterized by: In the electric drive device according to claim 12,
The shared fixing member is a fixing bolt having a thread at least at the tip thereof, and the screw of the fixing bolt is screwed into a threaded portion formed in the second spacer to connect the connector assembly and the first spacer. The circuit board, the first spacer, and the second circuit board are sandwiched and fixed.
An electric drive device characterized by: 14. The electric drive device according to claim 13,
The second spacer includes a fitting and fixing portion that passes through a through hole provided in the third circuit board and fits into a fitting and fixing hole formed in the end wall.
An electric drive device characterized by: In the electric drive device according to claim 7,
the third circuit board is a power conversion circuit board provided with a power conversion circuit for driving the electric motor;
The first circuit board is a control circuit board provided with a control circuit for controlling a power conversion circuit that drives the electric motor,
The second circuit board is a power supply circuit board provided with a power supply circuit for generating power for the power conversion circuit and the control circuit.
An electric drive device characterized by:

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