Electric pump

Abstract

To ensure insulation in a case where a high voltage is applied in an electric pump.SOLUTION: An electric pump comprises: a motor which drives the pump; a control board which controls the motor; a terminal which electrically connects the motor and the control board; a conductive holder which is disposed between the motor and the control board; and an insulative terminal guide which is disposed between the terminal and the holder. In the terminal guide, a processing section is provided which makes a creepage distance between the terminal and the holder longer than that before processing.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an electric pump. [Background technology]

[0002] Patent Document 1 discloses a motor configuration in which a busbar holder made of an insulating material has a cylindrical terminal guide portion that extends axially and is disposed inside the terminal through-hole, and the busbar terminals and circuit terminals are connected and housed inside. In this way, both the busbar terminals and the circuit terminals are housed inside the terminal guide portion. Therefore, both the busbar terminals and the circuit terminals are reliably insulated from the bearing holder, preventing the occurrence of short circuits. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-51737 Summary of the Invention [Problem to be solved by the invention]

[0004] In the configuration of Patent Document 1, the occurrence of a short circuit can be prevented by the terminal fixing structure. However, although application of a high voltage to an electric pump has been considered, insulation failure that may occur when such a high voltage is applied has not been taken into consideration.

[0005] The present invention has been made in view of the above-mentioned problems, and has an object to ensure insulation in an electric pump when a high voltage is applied thereto. [Means for solving the problem]

[0006] In order to achieve the above object, an electric pump is provided which comprises a motor for driving the pump, a control board for controlling the motor, a terminal for electrically connecting the motor and the control board, a conductive holder provided between the motor and the control board, and an insulating terminal guide provided between the terminal and the holder, and the terminal guide is provided with a processed portion which makes the creepage distance between the terminal and the holder longer than before processing.

[0007] In this way, the electric pump is provided with a processed portion that increases the creepage distance between the terminals that electrically connect the motor and the control board and the holder compared to before processing. Therefore, even in cases where there is not enough space to form the holder, the creepage distance can be sufficiently increased. Therefore, insulation can be ensured even when high voltage is applied to the electric pump. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic cross-sectional view of an electric water pump according to an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view of a cross section of the electric water pump. [Figure 3] FIG. 10 is an enlarged view of a conventional holder. [Figure 4] FIG. 2 is an enlarged view of a holder according to the embodiment. [Figure 5] FIG. 10 is an enlarged view of a holder according to a modified example. [Figure 6] FIG. 10 is a diagram showing a processing unit according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] Here, the embodiment will be described in the following order. (1) Electric water pump configuration (2) Supplementary Note

[0010] (1) Electric water pump configuration Fig. 1 is a schematic cross-sectional view of an electric water pump 1 according to this embodiment. Fig. 2 is a perspective view of a schematic cross section of the electric water pump 1. The electric water pump 1 includes a pump 11, a motor 12 that drives the pump 11, and a driver 13 that controls the motor 12. The electric water pump 1 is an example of an electric pump.

[0011] The motor 12 is housed in a body housing 21 and includes a stator 121 and a rotor 122. An insulator 123 is provided between the stator 121 and the rotor 122.

[0012] The stator 121 includes a stator core 1211 and a coil 1212. The stator core 1211 is made of a plurality of electromagnetic steel plates laminated in the X-axis direction. Here, the X-axis is the rotation axis of the motor 12. The coil 1212 is wound around the stator core 1211 in a predetermined pattern. The coil 1212 is electrically connected to a control board 131 provided in the driver 13 via terminals 14.

[0013] The coil 1212 includes a U-phase coil, a V-phase coil, and a plurality of W-phase coil wires. Although one terminal 14 is shown in Figures 1 and 2, the stator 121 is actually provided with a total of four terminals 14, three terminals corresponding to the UVW phases and one neutral terminal.

[0014] The insulator 123 ensures insulation between the stator 121 and the rotor 122. The insulator 123 is made of a thermoplastic resin such as a PPS resin.

[0015] The driver 13 is housed in a driver housing 22 and includes a control board 131. A drive circuit for the motor 12 is mounted on the control board 131. A terminal 14 is electrically connected to the control board 131. FIG. 3 is an enlarged view of the periphery of the terminal 14. The configuration in FIG. 3 is not the configuration of this embodiment, but is an explanatory diagram of a short circuit. The terminal 14 is fixed via a terminal guide 210 in a holder 200 provided on the motor 12. The holder 200 is a plate-like member fixed to the body housing 21. Various components are fixed to the holder 200. The holder 200 is made of a conductive member. In this embodiment, the holder 200 is made of aluminum.

[0016] The terminals 14 are guided by terminal guides 210 and extend toward the control board 131. The terminal guides 210 are made of an insulating material. In this embodiment, the terminal guides 210 are made of resin. This ensures insulation between the terminals 14 and the holder 200. However, if a high voltage, such as 800 V, is applied to the terminals 14, short circuits may become a problem.

[0017] In FIG. 3, the creepage distance L1 is expressed by (Equation 1) L1=L11+L12 (Formula 1) In (Equation 1), L11 is the horizontal length of the terminal guide 210. L12 is the height of the terminal guide 210. Here, the horizontal direction is the direction perpendicular to the X-axis. The height of the terminal guide 210 is the length in the X-axis direction.

[0018] To prevent a short circuit from occurring, it is necessary to ensure a sufficiently long creepage distance L1. However, it may be difficult to ensure a sufficient creepage distance in the direction perpendicular to the X-axis due to the relationship with other components. Furthermore, if the distance in the X-axis direction between the control board 131 and the holder 200 is relatively long, it may be possible to ensure a sufficient creepage distance by making the terminal guide 210 long along the X-axis direction, but it may also be difficult to ensure a sufficient creepage distance in the X-axis direction.

[0019] In contrast, in the electric water pump 1 of this embodiment, as shown in FIG. 4 , a groove 212 is formed in the terminal guide 210 between the terminal 14 and the holder 200. The groove 212 is a processed portion processed into a concave shape. As a result, the creepage distance L2 is longer than the sum of the lateral length of the terminal guide 210 and the height of the terminal guide 210. In this way, by forming the groove 212, the creepage distance can be increased. Here, the groove 212 is configured to increase the creepage distance compared to before the groove 212 is formed, that is, it is an example of a processed portion that increases the creepage distance compared to before processing.

[0020] 5 is a view of the groove 212 as viewed in the X-axis direction. As shown, the groove 212 is formed in an annular shape.

[0021] As described above, in the electric water pump 1 according to this embodiment, the formation of the groove 212 in the terminal guide 210 increases the creepage distance between the terminal 14 and the holder 200, thereby preventing the occurrence of a short circuit. In other words, insulation can be ensured when a high voltage is applied to the electric pump. Furthermore, the groove 212 is formed in an annular shape, so that a sufficient creepage distance can be ensured around the entire periphery of the terminal 14.

[0022] (2) Supplementary Note The above embodiment is an example for carrying out the present invention, and various other embodiments can be adopted.

[0023] In such a modified example, the shape of the groove 212 is not limited to a circular ring, as long as it surrounds the periphery of the terminal 14. The groove 212 may be formed in an elliptical shape, for example.

[0024] Furthermore, when a sufficient creepage distance can be ensured around the terminal 14 in a predetermined direction, the groove 212 may be formed only in a part of the periphery of the terminal 14 .

[0025] Furthermore, the position where the groove 212 is formed is not limited to the embodiment. For example, the groove 212 may be formed on a side (portion having a length of L12) in the height direction of the terminal guide 210. That is, the groove 212 may be formed so as to be concave in the horizontal direction on a side of the terminal guide 210 in the height direction having a length of L12, as shown in FIG.

[0026] Furthermore, the processed portion for increasing the creepage distance is not limited to the groove portion 212. For example, the processed portion may be a tapered opening 214 formed in the terminal guide 210, as shown in FIG. 6. The opening 214 is formed so that its diameter increases from the holder 200 toward the motor 12 along the X-axis. In this case, the terminal 14 and the terminal guide 210 contact each other at an end point 2141 where the tapered opening begins to widen. Therefore, the configuration including the tapered opening 214 has a longer creepage distance than the configuration before the tapered opening is formed. [Explanation of symbols]

[0027] 1...electric pump, 11...pump, 12...motor, 13...driver, 21...body housing, 22...driver housing, 121...stator, 122...rotor, 123...insulator, 200...holder, 210...terminal guide, 212...groove portion, 214...opening, 1211...stator core, 1212...coil

Claims

1. a motor that drives the pump; a control board for controlling the motor; a terminal for electrically connecting the motor and the control board; a conductive holder provided between the motor and the control board; an insulating terminal guide provided between the terminal and the holder; Equipped with The terminal guide has a processed portion that makes the creepage distance between the terminal and the holder longer than before the processing.

2. The electric pump according to claim 1 , wherein the processed portion is a groove formed around the terminal.

3. The electric pump according to claim 2 , wherein the groove is formed in an annular shape.

4. The electric pump according to claim 1 , wherein the processed portion is a tapered opening whose diameter increases from the holder toward the motor.

Images