JP7415823B2 - rotating electric machine - Google Patents

Description

The present invention relates to a rotating electric machine.

2. Description of the Related Art Conventionally, there has been known a rotating electric machine in which a board on which a rotation angle detection element is mounted is housed in a housing, and the board is electrically connected to the outside through a terminal inserted into the housing. In Patent Document 1, a board connection terminal protruding straight from a housing is connected to the board.

Patent No. 4367204

In Patent Document 1, stress due to thermal stress or vibration is likely to be applied to the connection portion between the board and the terminal. Therefore, it is desirable to provide a structure that alleviates the stress. On the other hand, it is conceivable to provide a stress relaxation part in a portion of the terminal located in the space between the housing and the board.

However, when providing the above-mentioned stress relaxation section, a separate resin cutting member is required to prevent molten resin from flowing into the stress relaxation section during molding of the housing, which increases the number of parts. Furthermore, when resin cutting is performed using only a mold without using a resin cutting member, the structure of the mold becomes complicated and manufacturing becomes difficult.

The present invention has been made in view of the above-mentioned points, and its purpose is to provide a rotating electric machine that can be easily manufactured without increasing the number of parts and that can alleviate stress applied to terminal connections. It is.

The present invention includes a stator (31), a rotor (34) provided rotatably, a substrate (59) on which an element (58) for detecting the rotation angle of the rotor is mounted, and a stator, rotor, and substrate. It includes a housing (20) containing the housing, and terminals (61, 612, 613, 614, 616) inserted into the housing and extending from the external connection connector (27) of the housing to the board.

The terminal includes a connector part (71) held by the external connection connector, a connection part (72) connected to the board, and a terminal extending from the connector part to a position facing the space between the housing and the board. an extending portion (73, 732, 733, 736) that connects the extending portion and the connecting portion and has at least one bent portion (76, 761, 762) or a curved portion (74); ). A projected image (77) of the connecting portion and the stress relaxation portion projected onto the extending portion from a direction perpendicular to the substrate is contained within the extending portion.
If the direction perpendicular to the extending direction of the extending portion is defined as the width direction when viewed from the direction perpendicular to the substrate, the terminal extends over a predetermined range including at least the connecting portion and the stress relaxation portion in the extending direction of the extending portion. It has wall portions (78, 784, 786) that respectively protrude toward the substrate from both sides in the width direction of the extending portion.

By providing the stress relaxation portion in the space between the housing and the board in this manner, stress due to thermal stress or vibration is less likely to be applied to the connection portion of the terminal. This relieves stress on the connection and improves reliability.

In addition, when molding the housing or a part thereof, the space in the mold for housing the connection part and the stress relief part can be covered and sealed with the extension part, so that molten resin does not flow into the stress relief part. The resin can be cut like this. In other words, it is possible to perform resin cutting using the terminal without using a separate resin cutting member and without complicating the structure of the mold for resin cutting. Therefore, it can be easily manufactured without increasing the number of parts.

FIG. 1 is a schematic diagram illustrating a shift-by-wire system to which a rotary actuator including a motor according to a first embodiment is applied. FIG. 2 is a cross-sectional view of the rotary actuator of FIG. 1; FIG. 3 is a partially enlarged view of FIG. 2. FIG. 4 is a view of the sensor terminal and primary molded body of FIG. 3 viewed from the direction of arrow IV. FIG. 5 is a cross-sectional view of a mold for forming the primary molded body of FIG. 4; FIG. 6 is a sectional view taken along the line VI-VI of the mold shown in FIG. 5. FIG. 7 is a diagram showing a sensor terminal and a primary molded body according to a second embodiment. FIG. 8 is a cross-sectional view of a mold for forming the primary molded body of FIG. 7; FIG. 9 is a sectional view taken along line IX-IX of the mold shown in FIG. 8; FIG. 7 is a diagram showing a sensor terminal and a primary molded body according to a third embodiment. FIG. 12 is a cross-sectional view of a mold for forming the primary molded body of FIG. 10. FIG. 12 is a sectional view taken along line XII-XII of the mold shown in FIG. 11. FIG. 7 is a sectional view showing a sensor terminal according to a fourth embodiment and a mold for forming a primary molded body. 14 is a sectional view taken along the line XIV-XIV of the mold shown in FIG. 13. FIG. 7 is a cross-sectional view showing a sensor terminal according to a fifth embodiment and a mold for forming a primary molded body. 16 is a sectional view taken along the line XVI-XVI of the mold shown in FIG. 15. FIG. 7 is a cross-sectional view showing a sensor terminal according to a sixth embodiment and a mold for forming a primary molded body. 18 is a sectional view taken along the line XVIII-XVIII of the mold shown in FIG. 17.

Hereinafter, a plurality of embodiments of a motor as a rotating electric machine will be described based on the drawings. Substantially the same configurations in the embodiments are denoted by the same reference numerals, and description thereof will be omitted.

[First embodiment]
As shown in FIG. 1, a motor 30 as an inner rotor type rotating electrical machine of the first embodiment is included in a rotary actuator (hereinafter referred to as an actuator) 10. Actuator 10 is fixed to the outer wall of case 12 of vehicle transmission 11 and is used as a power source for shift-by-wire system 13 . In the shift-by-wire system 13, a control device 15 controls an actuator 10 in response to a command signal from a shift operation device 14, thereby operating a shift range switching mechanism 16 of a transmission 11 to switch the shift range.

(actuator)
First, the overall configuration of the actuator 10 will be described with reference to FIG. 2. The actuator 10 includes a housing 20, a motor 30, and a reduction gear 40.

The housing 20 has a cup-shaped front housing 21 and a rear housing 22. The front housing 21 and the rear housing 22 are fastened to each other by bolts 23 with their openings combined. A bottomed cylindrical metal plate 24 is inserted into the front housing 21 . The rear housing 22 has a cylindrical protrusion 28 that protrudes on the opposite side from the front housing 21 . A bracket 29 is fixed to the outer wall of the rear housing 22. The actuator 10 is fixed to the case 12 (see FIG. 1) of the transmission 11 using a bracket 29.

Motor 30 has a stator 31 and a rotor 34 housed in housing 20. The stator 31 includes a stator core 32 fixed to the metal plate 24 by, for example, press fitting, and a winding 33 provided on the stator core 32. The rotor 34 includes a rotating shaft 37 rotatably supported around the rotational axis AX1 by a motor-side bearing 35 and a reducer-side bearing 36, and a rotor core 38 fitted and fixed to the outside of the rotating shaft 37. . The motor side bearing 35 is provided on the metal plate 24. The reduction gear side bearing 36 is provided in an output member 44, which will be described later.

The speed reducer 40 includes an eccentric shaft 41, a ring gear 42, an eccentric gear 43, an output member 44, and a transmission mechanism 45. The eccentric shaft 41 is provided on an eccentric axis AX2 that is eccentric with respect to the rotation axis AX1, and is formed integrally with the rotation axis 37. The ring gear 42 is provided coaxially with the rotation axis AX1 and is fixed to the rear housing 22. The eccentric gear 43 has an external toothed portion 47 that meshes with the internal toothed portion 46 of the ring gear 42, and is supported by a bearing 48 provided on the eccentric shaft 41 so as to be capable of planetary movement. The planetary motion is a motion in which the object rotates around the eccentric axis AX2 and revolves around the rotation axis AX1. The rotational speed of the eccentric gear 43 during planetary motion is varied relative to the rotational speed of the rotating shaft 37.

The output member 44 is provided coaxially with the rotation axis AX<b>1 and rotatably supported by a bearing 49 provided in the rear housing 22 . The transmission mechanism 45 includes an engagement protrusion 51 formed on the eccentric gear 43 and an engagement hole 52 formed on the output member 44 into which the engagement protrusion 51 is inserted. The rotation around the output member 44 is transmitted to the output member 44 .

In the actuator 10, a rotating magnetic field is generated by switching the energized phase of the winding 33, and the rotor 34 rotates in response to magnetic attraction or repulsion generated by the rotating magnetic field. When the eccentric shaft 41 rotates together with the rotor 34 around the rotation axis AX1, the eccentric gear 43 makes a planetary motion, and the rotation of the eccentric gear 43 that is decelerated relative to the rotation of the rotor 34 is output from the output member 44.

(External connection structure)
Next, a configuration for connecting the substrate 59 on which the rotation angle detection element is mounted to the outside will be described. Hereinafter, a direction parallel to the substrate 59 will be referred to as a "substrate plane direction." The above-mentioned "external" refers to a portion outside of the components of the actuator 10.

As shown in FIG. 2, the actuator 10 includes a magnet 57 provided in the rotor core 38, a magnetic sensor 58 that is an element that detects the rotation angle of the rotor 34, and outputs a signal according to the magnetism of the magnet 57. A substrate 59 on which a magnetic sensor 58 is mounted is provided.

The front housing 21 includes a cylindrical portion 25, a bottom portion 26, and a connector 27 for external connection, which constitute a main body portion made of resin. The external connection connector 27 is formed on the outside of the cylindrical portion 25 . The external connector 17 is detachably connected to the external connection connector 27 . External connector 17 holds external power terminal 18 and external signal terminal 19.

A plurality of motor terminals and a plurality of sensor terminals 61 (not shown) are inserted into the front housing 21. The motor terminal is a terminal that electrically connects the winding 33 to the outside. The sensor terminal 61 is a terminal that electrically connects the board 59 to the outside.

As shown in FIGS. 2 and 3, the motor terminal and sensor terminal 61 are inserted into the front housing 21. In the first embodiment, the front housing 21 includes a primary molded body 62 that integrates a motor terminal and a sensor terminal 61, and a secondary molded body 63 into which the primary molded body 62 is inserted. The primary molded body 62 is inserted into a through hole 64 formed in the metal plate 24. The sensor terminal 61 extends from the external connection connector 27 through the cylindrical portion 25 and the bottom portion 26 to the substrate 59.

A space 65 is defined between the bottom 26 of the front housing 21 and the substrate 59. The sensor terminal 61 includes a connector section 71 held by the external connection connector 27, a connection section 72 connected to the board 59, and an extension section 73 extending from the connector section 71 to a position facing the space 65. and a stress relaxation part 74 that connects the extension part 73 and the connection part 72.

An end portion of the extending portion 73 on the substrate 59 side (hereinafter referred to as a substrate side end portion 75) extends along the inner wall of the bottom portion 26 in the plane direction of the substrate. The extending direction of the substrate side end portion 75 is the same as the substrate plane direction. The sensor terminal 61 is inserted into the primary molded body 62 so that the substrate side end 75 is exposed to the internal space of the housing 20 .

The stress relaxation portion 74 has at least one bent or curved portion to absorb changes in the relative position between the front housing 21 and the substrate 59 due to temperature changes or vibrations. This relieves the stress applied to the connection portion 72. In the first embodiment, the stress relaxation part 74 has two bent parts 76. Specifically, the stress relaxation part 74 extends from the tip of the board-side end part 75 toward the board 59, and then bends toward the connector part 71 side in the extending direction of the board-side end part 75. It has a bent portion 761 and a second bent portion 762 that extends toward the connector portion 71 in the extending direction of the board side end portion 75 and then bends toward the board 59. When the first bent part 761 and the second bent part 762 are not distinguished, they are referred to as a bent part 76.

As shown in FIG. 4, the direction perpendicular to the extending direction of the substrate side end portion 75 when viewed from the direction perpendicular to the substrate 59 (hereinafter referred to as the substrate perpendicular direction) is defined as the width direction. Further, the length in the width direction is referred to as "width". The width w1 of the connecting portion 72 and the stress relaxation portion 74 is the same as the width w2 of the substrate side end portion 75. When viewed in the direction perpendicular to the substrate, the entire connecting portion 72 and stress relaxation portion 74 completely overlap the substrate side end portion 75. In other words, a projected image 77 of the connecting portion 72 and the stress relaxation portion 74 projected onto the extending portion 73 from the direction perpendicular to the substrate is contained within the extending portion 73 . In FIG. 4, the projected image 77 is indicated by double-dashed line hatching.

The primary molded body 62 is manufactured using a mold 80 shown in FIGS. 5 and 6. The mold 80 includes a first mold 81 that holds the connector portion 71, a second mold 82 that forms a portion of the primary molded body 62 that corresponds to the cylindrical portion 25 (see FIG. 3), and the primary molded body 62. It has a third mold 83 that forms a portion corresponding to the bottom portion 26 (see FIG. 3). The extending portion 73 is installed at the boundary between the second mold 82 and the third mold 83.

In order to completely expose the connecting part 72 and the stress relaxing part 74 outside the primary molded body 62 (see FIG. 3), the second mold 82 has a sealed space 84 for accommodating the connecting part 72 and the stress relaxing part 74. have The width of the sealed space 84 is the same as the width of the substrate side end 75. Therefore, the substrate side end portion 75 can cover the sealed space 84 to seal the sealed space 84, and by isolating the sealed space 84 from the cavity 85 through which the molten resin flows, the molten resin can pass through the stress relaxation area. The resin can be cut to prevent it from flowing into 74.

(effect)
As described above, in the first embodiment, the motor 30 includes the sensor terminal 61 inserted into the front housing 21 and extending from the external connection connector 27 to the board 59. The sensor terminal 61 includes a connector section 71 held by the external connection connector 27, a connection section 72 connected to the board 59, and an extension section 73 extending from the connector section 71 to a position facing the space 65. and a stress relaxation part 74 that connects the extension part 73 and the connection part 72. A projected image 77 of the connecting portion 72 and the stress relaxation portion 74 projected onto the extending portion 73 from a direction perpendicular to the substrate 59 is contained within the extending portion 73 .

By providing the stress relaxation portion 74 in the space between the front housing 21 and the substrate 59 in this manner, stress due to cold stress or vibration is less likely to be applied to the connection portion 72. As a result, the stress applied to the connecting portion 72 is alleviated, and the reliability of the detected value is improved.

Further, when molding the primary molded body 62, the closed space 84 in the mold 80 for accommodating the connection part 72 and the stress relaxation part 74 can be closed by covering it with the extension part 73, so that the molten resin is not exposed to stress. The resin can be cut so that it does not flow into the relaxation part 74. In other words, resin cutting can be performed using the sensor terminal 61 without using a separate resin cutting member and without complicating the structure of the mold 80 for resin cutting. Therefore, it can be easily manufactured without increasing the number of parts.

Further, in the first embodiment, the width w1 of the connecting portion 72 and the stress relaxation portion 74 is the same as the width w2 of the substrate side end portion 75. This makes it easier to design the unfolded shape of the sensor terminal 61.

Further, in the first embodiment, the front housing 21 includes a primary molded body 62 in which a plurality of sensor terminals 61 are integrated, and a secondary molded body 63 into which the primary molded body 62 is inserted. Thereby, the secondary molded body 63 can be molded in a state in which the plurality of sensor terminals 61 are integrated, so that the secondary molded body 63 can be easily molded. In particular, molding of the external connection connector 27 becomes easier.

[Second embodiment]
In the second embodiment, as shown in FIG. 7, the width w1 of the connection portion 72 and stress relaxation portion 74 of the sensor terminal 612 is smaller than the width w2 of the substrate side end portion 752. When viewed in the direction perpendicular to the substrate, the entire connecting portion 72 and stress relaxation portion 74 completely overlap the substrate side end portion 752. That is, a projected image 77 of the connecting portion 72 and the stress relaxation portion 74 projected onto the extending portion 732 from the direction perpendicular to the substrate is contained within the extending portion 732 .

As shown in FIGS. 8 and 9, the substrate side end portion 752 is installed at the edge of the opening of the sealed space 84. As shown in FIGS. The width w2 of the substrate side end portion 752 is larger than the width w3 of the sealed space 84 and smaller than the width w4 of the cavity 85. The substrate side end portion 752 can contact the opening edge of the sealed space 84 to seal the sealed space 84, and by isolating the cavity 85 and the sealed space 84, molten resin does not flow into the stress relaxation part 74. The resin can be cut like this. According to the second embodiment, the same effects as the first embodiment can be obtained.

Furthermore, in the second embodiment, the width w1 of the projected image is smaller than the width w2 of the substrate side end 752. Therefore, even if the width w3 of the sealed space 84 is set larger than the width w1 of the projected image, the sealed space 84 can be sealed by the substrate side end 752. Thereby, since the width w3 of the sealed space 84 is larger than the width w1 of the projected image, it is possible to prevent the connection part 72 and the stress relaxation part 74 from interfering with the mold 80 during molding.

[Third embodiment]
In the third embodiment, as shown in FIGS. 10 to 12, the sensor terminal 613 extends over a predetermined range of the extending portion 733 including at least the connecting portion 72 and the stress relaxation portion 74 in the extending direction of the extending portion 733. It has wall portions 78 that protrude from both sides of the substrate side end portion 753 in the width direction toward the substrate 59 (see FIG. 3) (that is, toward the connecting portion 72 side).

The substrate side end portion 753 is installed at the opening of the sealed space 84 . The width w2 of the substrate side end portion 753 is the same as the width w3 of the sealed space 84 and the width w4 of the cavity 85. The wall portion 78 can contact the inner wall surface of the second mold 823 of the mold 803 that partitions the sealed space 84 to seal the sealed space 84 together with the substrate side end portion 753, and separate the cavity 85 and the sealed space 84 from each other. By isolating the stress relief portion 74, the resin can be cut so that the molten resin does not flow into the stress relaxation portion 74. According to the third embodiment, effects similar to those of the first embodiment can be obtained.

Furthermore, in the third embodiment, by providing the wall portion 78, the shape can be easily changed in consideration of manufacturing the mold 803, and contact between the stress relaxation portion 74 and the connecting portion 72 and the mold 803 can be prevented. can.

[Fourth embodiment]
In the fourth embodiment, as shown in FIGS. 13 and 14, the wall portion 784 protrudes from the board side end portion 753 toward the connection portion 72, and then curves outward in the width direction to the side opposite to the connection portion 72. It is formed to extend to. As a result, the portion of the wall portion 784 that is inserted into the second mold 824 has a curved surface, so that the contact state between the wall portion 784 and the second mold 824 is good, and the life of the mold 804 is extended. I can do it.

[Fifth embodiment]
In the fifth embodiment, as shown in FIGS. 15 and 16, the wall portion 78 comes into contact with the contact surface 86 of the second mold 825 of the mold 805 during molding of the primary molded body. Thereby, the shape of the second mold 825 in contact with the wall portion 78 becomes simple, and the life of the mold 805 can be extended.

[Sixth embodiment]
In the sixth embodiment, as shown in FIGS. 17 and 18, the mold 806 includes a first mold 816 and a second mold 826. The wall portion 786 of the sensor terminal 616 extends over a predetermined range from the combination of the first mold 816 and the second mold 826 of the mold 806 to the tip of the extension portion 736, and extends from both sides of the extension portion 736 in the width direction. They each protrude toward the connecting portion 72 side. The end surface 87 of the wall portion 786 in the protruding direction is inclined such that the protruding length of the wall portion 786 becomes shorter from the connector portion 71 side toward the stress relaxation portion 74 side. Thereby, the mold 806 can be made into a two-part mold consisting of the first mold 816 and the second mold 826, making it easier to manufacture the primary molded body.

[Other embodiments]
In other embodiments, the stress relief portion may have one bend or more than two bends. Moreover, the stress relaxation part is not limited to a bent part, and may be configured to have a curved part. Further, the extending portion of the sensor terminal may be formed not only straight but also bent or curved midway.

In other embodiments, the resin portion of the housing may be constructed from one molded body.

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

20 housing, 27 external connection connector, 31 stator, 34 rotor,
58 magnetic sensor (element), 59 substrate,
61,612,613,614,616 Sensor terminal (terminal),
71 Connector part, 72 Connection part, 73, 732, 733, 736 Extension part,
74 Stress relaxation part, 76, 761, 762 Bent part, 77 Projection image.

Claims (4)

a stator (31);
a rotor (34) rotatably provided;
a substrate (59) on which an element (58) for detecting the rotation angle of the rotor is mounted;
a housing (20) containing the stator, the rotor and the substrate;
a terminal (61, 612, 613, 614, 616) inserted into the housing and extending from the external connection connector (27) of the housing to the board;
Equipped with
The terminal includes a connector part (71) held by the external connection connector, a connection part (72) connected to the board, and a space between the housing and the board from the connector part. The extension part (73, 732, 733, 736) extending to a position facing (65) connects the extension part and the connection part and has at least one bent part (76, 761, 762). ) or a stress relaxation part (74) having a curved part,
A projected image (77) of the connecting portion and the stress relaxation portion projected onto the extending portion from a direction perpendicular to the substrate fits within the extending portion;
When the direction perpendicular to the extending direction of the extending portion is defined as the width direction when viewed from the direction perpendicular to the substrate,
The terminal includes wall portions (78, 78, 784, 786) . When the direction perpendicular to the extending direction of the extending portion is defined as the width direction when viewed from the direction perpendicular to the substrate,
The rotating electric machine according to claim 1, wherein a length (w1) of the projected image in the width direction is smaller than a length (w2) of the extension portion in the width direction. The end surface (87) of the wall portion in the protruding direction is inclined such that the protruding length of the wall portion decreases from the connector portion side toward the stress relaxation portion side. rotating electric machine. Any one of claims 1 to 3 , wherein the housing includes a primary molded body (62) that integrates a plurality of the terminals, and a secondary molded body (63) in which the primary molded body is inserted. The rotating electric machine described in .

Images