JP2023115467A - Driving device - Google Patents

Abstract

To provide a driving device in which a control section can be protected against noise while suppressing the increase in size and production cost.SOLUTION: A driving device 10 includes integrally a motor 20 and a control unit 40 that controls the motor 20. The control unit 40 includes a substrate 41, a power wiring pattern 51 provided on the substrate 41, a driving section 61 that drives the motor 20 with large current supplied from the power wiring pattern 51, and a control section 62 that communicates a signal with small current. The power wiring pattern 51 includes a main body wiring section 54 that is located such that the control section 62 is disposed between the main body wiring section 54 and a metal frame 33 of the motor 20.SELECTED DRAWING: Figure 2

Description

The present invention relates to a driving device.

2. Description of the Related Art Conventionally, as disclosed in Japanese Unexamined Patent Application Publication No. 2002-100001, a drive device that integrally includes a motor and a control unit is known. In Patent Document 1, a control board of a control unit is arranged on a frame as a heat sink, and a metal shield plate is arranged on the side opposite to the frame with respect to the control board.

Japanese Patent No. 6633213

In the control unit of Patent Literature 1, noise countermeasures are implemented by sandwiching the board between the frame and the shield plate. However, the addition of the shield plate increases the number of parts, leading to an increase in size and manufacturing costs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object thereof is to provide a driving device capable of protecting a control unit from noise while suppressing increases in size and manufacturing costs.

The driving device of the present invention integrally includes a motor (20) and a control unit (40) for controlling the motor. The control unit includes substrates (41, 71), a power wiring pattern (51) provided on the substrate, a driving section (61) that drives the motor with a large current supplied from the power wiring pattern, and a signal with a small current. and a control unit (62) that communicates with. The power wiring pattern has body wiring portions (54, 55) arranged so as to sandwich the control portion between the metal frame (33) of the motor.

As a result, the control unit is sandwiched between the main body wiring portion of the power wiring pattern, which has a suitable conductor capacity to allow a large current to flow, and the frame, which is made of metal and has a large conductor capacity. Therefore, the body wiring portion and the frame absorb radiation noise from the outside, thereby protecting the control portion from the noise and suppressing malfunction. In addition, since the board has a noise shielding function without adding parts, it is possible to suppress an increase in size and manufacturing cost.

FIG. 2 is a longitudinal sectional view of the driving device of the first embodiment; FIG. 2 is an enlarged view of part II of FIG. 1; The figure which looked at the board|substrate of FIG. 2 from the arrow III direction. The figure which looked at the board|substrate of FIG. 2 from the arrow IV direction. FIG. 4 is an enlarged view of the substrate of the second embodiment, corresponding to FIG. 2 of the first embodiment;

A plurality of embodiments will be described below with reference to the drawings. The same reference numerals are assigned to substantially the same configurations between the embodiments, and the description thereof is omitted.

[First embodiment]
As shown in FIG. 1, the driving device 10 integrally includes a motor 20 and a control unit 40 for controlling it. The control unit 40 controls the motor 20 to generate a desired torque based on externally input information and information such as motor current detected inside the control unit 40 . Torque of the motor 20 is output from the output end of the rotating shaft 26 to the outside.

The motor 20 is a three-phase brushless motor and includes a stator 21, a rotor 25, and a housing 31 that accommodates them. Stator 21 has stator core 22 fixed to housing 31 and three-phase winding set 23 assembled to stator core 22 . The three-phase winding set 23 is connected to the control unit 40 via lead wires (not shown).

The rotor 25 has a rotating shaft 26 rotatable relative to the stator 21 and a rotor core 27 in which the rotating shaft 26 is fitted. A permanent magnet 28 is provided at one end of the rotating shaft 26 . The housing 31 has a cylindrical motor case 32 and a metal frame 33 provided at one end of the motor case 32 . Frame 33 also functions as a heat sink for control unit 40 .

As shown in FIGS. 1 to 4, the control unit 40 is connected to a substrate 41, a power wiring pattern 51 provided on the substrate 41, and the power wiring pattern 51, and is supplied with a large current from the power wiring pattern 51. It has a drive section 61 that drives the motor 20 , a control section 62 that communicates signals with a small current, and a rotational position sensor 63 . The substrate 41 and the like are covered with a resin cover 64 for preventing foreign matter from entering.

A large current flowing through the power wiring pattern 51 is larger than a small current flowing through the control section 62 . The power wiring pattern 51 is secured with a suitable conductor capacity to allow a large current to flow.

The control unit 62 is provided on one surface 42 of the substrate 41 , and the driving unit 61 is provided on the other surface 43 of the substrate 41 . Drive unit 61 is an inverter circuit that supplies current to motor 20 and includes a plurality of switching elements (not shown). The control unit 62 calculates a control amount corresponding to a current for generating a desired motor torque based on various information, and outputs a drive signal to the drive unit 61 .

The substrate 41 is arranged on the rotation axis O of the motor 20 so that the control section 62 side faces the frame 33 , and is fixed to the frame 33 by screws 65 . The control unit 62 is arranged on the surface 42 of the substrate 41 on the frame 33 side. The drive unit 61 is arranged on the surface 43 of the substrate 41 opposite to the frame 33 .

The substrate 41 is a multi-layer substrate in which a wiring pattern is also provided in a portion that serves as an intermediate layer. A first layer 45 and a second layer 46 are defined in order from the layer farthest from the frame 33 in the substrate 41 . In addition, the layers of the substrate 41 that are closest to the frame 33 are defined as the bottom layer 49 and the bottom two layers 48 in this order. The driving part 61 is arranged on the first layer 45 . The control unit 62 is arranged on the bottom layer 49 .

The power wiring pattern 51 includes a power supply pattern 52 connected to the high potential side of the drive section 61 and a ground pattern 53 connected to the low potential side of the drive section 61 . The power pattern 52 is formed so as to surround the outer circumference of the first layer 45 .

The ground pattern 53 has main wiring portions 54 and 55 , an annular wiring portion 56 and a connection wiring portion 57 . The main body wiring portions 54 and 55 are arranged so as to sandwich the control portion 62 between them and the frame 33 , and are formed in a wider range than the control portion 62 when viewed in the plate thickness direction of the substrate 41 . In the first embodiment, the main body wiring portion 54 is a ground pattern for the driving portion 61, and is arranged on the entire second layer 46 of the substrate 41, which is the layer on the opposite side of the frame 33 with respect to the control portion 62. It is The main body wiring portion 55 is a ground pattern for the control portion 62 and is arranged on the entire lower two layers 48 of the substrate 41 on the opposite side of the frame 33 with respect to the control portion 62 . The main wiring portions 54 and 55 are solid patterns formed on the entire layer. Although the body wiring portion 55 is not connected to the body wiring portion 54, both may be connected in other embodiments.

The annular wiring portion 56 is arranged between the main body wiring portion 54 and the frame 33 and is formed so as to surround the control portion 62 when viewed in the plate thickness direction. In the first embodiment, the annular wiring portion 56 is formed so as to surround the outer periphery of the bottom layer 49, which is the layer in which the control portion 62 is arranged.

The connection wiring portion 57 is formed to extend from the body wiring portion 54 to the frame 33 . In the first embodiment, the connection wiring portion 57 extends from the second layer 46 to the bottom layer 49 through the through holes 44 of the substrate 41 . Both the connection wiring portion 57 and the annular wiring portion 56 are in contact with the frame 33 . As a result, the heat of the driving portion 61 escapes from the body wiring portion 54 to the frame 33 through the connection wiring portion 57 and the annular wiring portion 56 . Furthermore, the heat of the driving part 61 is released to the frame 33 through the screw 65 .

(effect)
As described above, in the first embodiment, the power wiring pattern 51 has the main body wiring portion 54 arranged so as to sandwich the control portion 62 with the metal frame 33 of the motor 20 . As a result, the control unit 62 is sandwiched between the main wiring part 54 of the power wiring pattern 51, which has a suitable conductor capacity for passing a large current, and the frame 33, which is made of metal and has a large conductor capacity. Therefore, the body wiring portion 54 and the frame 33 absorb radiation noise from the outside, thereby protecting the control portion 62 from the noise and suppressing malfunction and the like. In addition, since the substrate 41 has a noise shielding function without adding parts, it is possible to suppress an increase in size and manufacturing cost.

In one embodiment, substrate 41 is a multi-layer substrate. The main body wiring portion 54 is provided on the entire second layer 46 of the substrate 41 , which is the layer on the side opposite to the frame 33 with respect to the control portion 62 . Since the large power wiring pattern 51 is arranged in a layer other than the layer in which the control section 62 is arranged, the noise shielding function of the substrate 41 can be further enhanced.

In the first embodiment, the power wiring pattern 51 has an annular wiring portion 56 formed so as to surround the control portion 62 at a position between the body wiring portion 54 and the frame 33 . As a result, the noise shielding function for the control section 62 can be further enhanced.

Further, in the first embodiment, the power wiring pattern 51 has the connection wiring portion 57 extending from the main body wiring portion 54 to the frame 33 . As a result, the controller 62 can be protected from noise, and the heat of the drive section 61 can be released to the frame 33 through the connection wiring section 57 .

[Second embodiment]
In the second embodiment, as shown in FIG. 5, the substrate 71 is a double-sided substrate having wiring patterns on both sides. The control unit 62 is provided on the surface 42 of the substrate 71 on the frame 33 side. The main body wiring portion 54 is provided on the entire surface 43 of the substrate 71 opposite to the frame 33 . Thus, the substrate 71 is not limited to a multilayer substrate, and may be a double-sided substrate. Even so, if the main body wiring portion 54 and the metal frame 33 are arranged so as to sandwich the control portion 62, the control portion 62 can be protected from noise.

[Other embodiments]
In another embodiment, the main wiring portion may be provided on the entirety of one or three or more of the layers other than the frame-side surface of the substrate. Further, the main wiring portion does not necessarily have to be provided on the entire surface or layer of the substrate, and may be provided on a part of the surface or layer. It is sufficient that the control section is placed between the wiring section of the main body and the frame.

In other embodiments, the power wiring traces do not necessarily have to contact the frame.

The present invention is not limited to the above-described embodiments, and can be embodied in various forms without departing from the scope of the invention.

10 drive device, 20 motor, 33 frame, 40 control unit,
41, 71 substrate, 51 power wiring pattern, 54, 55 body wiring part,
61 drive unit, 62 control unit.

Claims (5)

A driving device integrally comprising a motor (20) and a control unit (40) for controlling the motor,
The control unit includes substrates (41, 71), a power wiring pattern (51) provided on the substrate, a driving section (61) for driving the motor with a large current supplied from the power wiring pattern, a control unit (62) that communicates a signal with a small current;
The driving device, wherein the power wiring pattern has body wiring portions (54, 55) arranged so as to sandwich the control portion between itself and a metal frame (33) of the motor. The substrate (41) is a multilayer substrate,
2. The driving device according to claim 1, wherein said main body wiring portion is provided on at least one of the layers other than said frame-side surface (42) of said substrate. The control unit is provided on a surface (42) of the substrate (71) on the frame side,
2. The driving device according to claim 1, wherein said body wiring portion is provided on the entire surface (43) of said substrate opposite to said frame. 4. The power wiring pattern according to any one of claims 1 to 3, wherein said power wiring pattern has an annular wiring portion (56) formed so as to surround said control portion at a position between said body wiring portion and said frame. drive. The driving device according to any one of claims 1 to 4, wherein said power wiring pattern has a connection wiring portion (57) extending from said body wiring portion to said frame.

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