Terminal fastening structure

Abstract

A terminal fastening structure is provided with: a first terminal provided on a power line extending from a motor; a terminal block to which the first terminal is fastened using a bolt; and a second terminal provided on the terminal block, the second terminal being in contact with the first terminal when the first terminal is fastened to the terminal block, the first terminal comprising: a plate-shaped terminal body in which a through hole or notch through which the bolt is inserted is formed; and a protrusion protruding from the terminal main body, the protrusion being in contact with at least one of the second terminal and the terminal block in a circumferential direction centered on the rotation axis of the bolt.

Description

Technical Field

[0001] This specification relates to a terminal fastening structure for securing terminals to a terminal block. Background Technology

[0002] Japanese Patent Application Publication No. 2020-145888 discloses a busbar fixing structure comprising: a first busbar extending from a motor; and a second busbar fastened to the first busbar by bolts. The second busbar is cylindrical, and the cylindrical front end of the first busbar contacts the first busbar. Summary of the Invention

[0003] When the first busbar is fastened to the second busbar using bolts, torque is transmitted from the bolts to the first busbar. This torque allows the first busbar to rotate relative to the second busbar. In the cylindrical front end described in Japanese Patent Application Publication No. 2020-145888, even when the first busbar rotates relative to the second busbar, the contact area between the first and second busbars remains almost unchanged. However, the shape of the busbar is not limited to a cylindrical shape. This is because the shape of the busbar is limited by the space available for its arrangement. In other words, sometimes due to space limitations, it is impossible to choose a configuration and shape that does not change the contact area of ​​the busbar. The phenomenon of the contact area changing due to the rotation of the busbar becomes a cause of deviations in the contact area during mass production. This specification provides a technique for suppressing deviations in the contact area between the first and second terminals.

[0004] The terminal fastening structure disclosed in this specification includes: a first terminal disposed on a power line extending from a motor; a terminal block fastened to the first terminal by a bolt; and a second terminal disposed on the terminal block, which contacts the first terminal when the first terminal is fastened to the terminal block. The first terminal includes: a plate-shaped terminal body having a through hole or notch for the bolt to be inserted; and a protrusion protruding from the terminal body, the protrusion abutting against at least one of the second terminal and the terminal block in a circumferential direction about the rotation axis of the bolt.

[0005] According to the above structure, even if the first terminal rotates around the rotation axis of the bolt, the protrusion of the first terminal abuts against at least one of the second terminal and the terminal block in the circumferential direction around the rotation axis. That is, the rotation of the first terminal stops due to the protrusion. By stopping the rotation of the first terminal, deviation in the contact area between the first terminal and the second terminal can be suppressed.

[0006] The detailed description of the technology disclosed in this specification and further improvements are described in the following "Detailed Description". Attached Figure Description

[0007] Hereinafter, the features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described with reference to the accompanying drawings, in which the same reference numerals denote the same elements, and wherein:

[0008] Figure 1 This is a cross-sectional view of a motor unit with a terminal fastening structure.

[0009] Figure 2 This is a cross-sectional view of the terminal fastening structure along line II-II.

[0010] Figure 3 These are the top view, side view, and sectional view of terminal 1.

[0011] Figure 4 This is a cross-sectional view of the terminal fastening structure involved in the second embodiment. Detailed Implementation

[0012] Example 1

[0013] Structure of Motor Unit 2

[0014] Motor unit 2 includes the terminal fastening structure 4, motor 6, and housing 8 as described in this embodiment. Motor unit 2 is, for example, mounted in vehicles such as battery electric vehicles and hybrid electric vehicles. Motor 6 is used, for example, to generate driving torque for driving, and to generate electricity. Motor 6 is a three-phase AC motor. Additionally, XYZ coordinates are defined in the figure. The Y-axis is parallel to the rotation axis of motor 6.

[0015] The terminal fastening structure 4 is used for electrically connecting the three power lines 10 extending from the motor 6 and the three power lines 12 extending from the power conversion device (not shown). Each power line 10 and each power line 12 corresponds to a phase of a three-phase AC circuit. Here, the power conversion device is, for example, an inverter.

[0016] The housing 8 houses the motor 6. A terminal fastening structure 4 is provided on the side wall 8a of the housing 8. Here, the side wall 8a is a wall perpendicular to the rotation axis of the motor 6. Alternatively, in a modified example, the terminal fastening structure 4 may be provided on a wall of the housing 8 parallel to the rotation axis of the motor 6.

[0017] Structure of terminal fastening structure 4

[0018] The terminal fastening structure 4 includes three first terminals 20, a terminal block 24, and three second terminals 26. One first terminal 20 is connected to one second terminal 26. One first terminal 20 is located on one of the three power lines 10 extending from the motor. One second terminal 26 is located on one of the three power lines 12 extending from the power conversion device. Here, the power line 10 is, for example, stranded wire, and the power line 12 is, for example, an electric cable.

[0019] like Figure 2 As shown, the second terminal 26 is fixed to the terminal block 24. In the terminal block 24, the first terminal 20 is fastened with bolts 22. When the first terminal 20 is fastened to the terminal block 24, the surface of the second terminal 26 (i.e., the surface located in the positive direction of the Y-axis) is in contact with the back surface of the first terminal 20 (i.e., the surface located in the negative direction of the Y-axis).

[0020] like Figure 1 , Figure 2 As shown, terminal block 24 is mounted in an opening 8b formed in sidewall 8a. Terminal block 24 and opening 8b are sealed by a sealing member (not shown).

[0021] Figure 3 This shows the first terminal 20, which has separated from the terminal fastening structure 4. The upper left figure is the front view, and the upper right figure is the side view. Furthermore, the lower left figure is a sectional view taken along line III-III. Figure 3 The XYZ coordinates correspond to the front view.

[0022] The first terminal 20 has a plate-shaped terminal body 20a and a protrusion 20b. A through hole 20c for inserting a bolt 22 is formed in the terminal body 20a. Alternatively, in a modified example, a notch for inserting a bolt 22 may be formed in the terminal body 20a. The protrusion 20b protrudes from the terminal body 20a and is formed along the outer edge of the terminal body 20a.

[0023] The protrusion 20b comprises a protrusion body 20d and a secondary protrusion 20e. The protrusion body 20d extends from the outer edge of the terminal body 20a in the negative Y-axis direction. The secondary protrusion 20e extends from the front end of the protrusion body 20d in the negative X-axis direction. The protrusion body 20d and the secondary protrusion 20e are plate-shaped.

[0024] A tapered portion 20f is formed on the inner surface of the sub-protrusion 20e, which is opposite to the back side of the terminal body 20a (i.e., the surface located in the negative Y-axis direction). In the tapered portion 20f, the gap D between the terminal body 20a and the sub-protrusion 20e widens toward the front end of the sub-protrusion 20e.

[0025] like Figure 2As shown, when the first terminal 20 is fastened to the terminal block 24, the protruding body 20d abuts against the outer edge of the second terminal 26. Furthermore, the secondary protrusion 20e extends from the front end of the protruding body 20d along the back surface of the second terminal 26 (i.e., the surface located in the negative Y-axis direction). Additionally, the second terminal 26 is raised from the surface of the terminal block 24 due to a step difference, etc. That is, a gap exists between the back surface of the second terminal 26 and the surface of the terminal block 24. The secondary protrusion 20e enters this gap and extends along the back surface of the second terminal 26.

[0026] When the first terminal 20 is fastened to the terminal block 24 using bolt 22, the first terminal 20 rotates about the rotation axis R of bolt 22. Here, the outer edge of the second terminal 26 is located circumferentially about the rotation axis R. Therefore, when the first terminal 20 rotates about the rotation axis R of bolt 22, the protruding body 20d abuts against the outer edge of the second terminal 26. That is, the rotation of the first terminal 20 stops due to the protruding body 20d. By stopping the rotation of the first terminal 20, deviations in the contact area between the first terminal 20 and the second terminal 26 during mass production can be suppressed.

[0027] Here, as Figure 3 As shown, the protrusion 20b is positioned away from the rotation axis R of the through hole 20c, i.e., the bolt 22. For example, the through hole 20c is located between the center of the terminal body 20a in the longitudinal direction (i.e., the Z-axis direction) and one end of the terminal body 20a in the longitudinal direction. On the other hand, the protrusion 20b is located between the center of the terminal body 20a in the longitudinal direction and the other end of the terminal body 20a in the longitudinal direction. By moving the protrusion 20b away from the through hole 20c, the load on the connection between the protrusion 20b and the terminal body 20a caused by the torque applied by rotating the bolt 22 can be reduced.

[0028] Furthermore, the first terminal 20 vibrates as the vehicle equipped with the motor unit 2 travels. In this embodiment, the terminal body 20a and the secondary protrusion 20e clamp the second terminal 26. As a result, the terminal body 20a is unlikely to vibrate along the Y-axis direction.

[0029] Furthermore, the cone portion 20f allows the second terminal 26 to be easily inserted into the gap between the terminal body 20a and the secondary protrusion 20e.

[0030] Correspondence

[0031] Terminal fastening structure 4, housing 8, and opening 8b are examples of "terminal fastening structure," "housing," and "opening," respectively. Motor 6 and power line 10 are examples of "motor" and "power line," respectively. Terminal 1 20, terminal body 20a, and protrusion 20b are examples of "terminal 1," "terminal body," and "protrusion," respectively. Protrusion body 20d, secondary protrusion 20e, and through hole 20c are examples of "protrusion body," "secondary protrusion," and "through hole," respectively. Cone 20f is an example of "cone." Bolt 22, terminal block 24, and second terminal 26 are examples of "bolt," "terminal block," and "second terminal," respectively. Rotating shaft R and interval D are examples of "rotating shaft" and "interval," respectively.

[0032] Example 2

[0033] This embodiment has the same structure as the first embodiment, except that the protrusion 20b lacks the secondary protrusion 20e. In this embodiment, when the first terminal 20 is fastened to the terminal block 24 using the bolt 22, the protrusion body 20d abuts against the outer edge of the second terminal 26, and the rotation of the first terminal 20 stops. The absence of the secondary protrusion 20e in this embodiment simplifies the structure compared to the first embodiment.

[0034] The following describes some considerations related to the technology shown in the embodiments. In the second embodiment, the protruding body 20d can extend from the back side of the terminal body 20a of the first terminal 20 toward the second terminal 26. Furthermore, a recess for accommodating the protruding body 20d can be formed on the surface of the second terminal 26. In this modified example, the protruding body 20d abuts against the inner surface of the recess of the second terminal 26 in the circumferential direction centered on the rotation axis R of the bolt 22.

[0035] Furthermore, in the second embodiment, the protruding body 20d can abut against a portion of the terminal block 24 to replace the second terminal 26.

[0036] Furthermore, in the first embodiment, the secondary protrusion 20e may not have a cone portion 20f formed.

Claims

1. A terminal fastening structure, characterized in that, It comprises: a first terminal disposed on a power line extending from a motor; a terminal block fastened to the first terminal by bolts; and a second terminal disposed on the terminal block, which contacts the first terminal when the first terminal is fastened to the terminal block. The first terminal includes: a plate-shaped terminal body having a through hole or notch for the bolt to be inserted; and a protrusion protruding from the terminal body, the protrusion abutting against at least one of the second terminal and the terminal block in a circumferential direction about the rotation axis of the bolt.

2. The terminal fastening structure according to claim 1, characterized in that, The protrusion is formed along the outer edge of the terminal body and abuts against the outer edge of the second terminal.

3. The terminal fastening structure according to claim 2, characterized in that, The protrusion comprises: a protrusion body that abuts against the outer edge of the second terminal; and a secondary protrusion that extends from the front end of the protrusion body along the back side of the second terminal.

4. The terminal fastening structure according to claim 3, characterized in that, On the inner surface of the sub-protrusion opposite to the back side of the second terminal, a tapered portion is formed such that the gap between the terminal body and the sub-protrusion widens toward the front end of the sub-protrusion.

5. The terminal fastening structure according to any one of claims 1 to 4, characterized in that, The terminal block is mounted on an opening formed in the housing that accommodates the motor.

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