Oil cooling system of electric drive axle

Abstract

The present invention provides an oil cooling system for an electric drive axle, wherein a first end cover oil circuit is provided on the end cover, a first insulating seat oil circuit and a second insulating seat oil circuit are provided on the insulating seat, and a drainage channel is provided at the overlapping portion; one end of the first insulating seat oil circuit is connected to the first end cover oil circuit, and the other end is connected to the drainage channel; one end of the second insulating seat oil circuit is connected to the drainage channel, and the other end is directed toward the motor copper part; the cooling oil in the first end cover oil circuit flows to the drainage channel at the overlapping portion through the first insulating seat oil circuit, and then flows back to the insulating seat through the second insulating seat oil circuit, and is sprayed toward the first section of the motor copper part, thereby cooling the insulating seat, the motor copper busbar and / or the controller copper busbar, and then flows to the winding by gravity to cool the winding.

Description

Technical Field

[0001] The present invention relates to the technical field of electric drive axles, and in particular to an oil cooling system of an electric drive axle. Background Art

[0002] In a bridge system, the controller and motor are connected via copper busbars to conduct current. However, due to contact resistance, the copper busbar connections heat up when high current flows through them. When the bridge operates continuously at high torque, the copper busbar connections continue to heat up, potentially leading to component failure within the cavity.

[0003] The existing technology makes a cooling structure at the insulating seat or the motor high-voltage cover plate. The active cooling of the insulating block can promptly remove the heat at the copper busbar connection position to avoid failure. Summary of the Invention

[0004] In order to overcome the above technical defects, the object of the present invention is to provide an oil cooling system that can cool the copper busbars and motor windings of an electric drive axle.

[0005] The present invention discloses an oil cooling system for an electric drive axle, comprising a motor copper busbar and a controller copper busbar of a motor controller; the motor copper busbar comprises a plurality of motor copper parts, and the controller copper busbar comprises a plurality of controller copper parts; a first section of the motor copper part is bent and connected to the motor, and a second section is overlapped with one end of the controller copper part, thereby connecting the motor copper busbar and the controller copper busbar, thereby electrically connecting the motor and the motor controller; the overlapping portion of the motor copper busbar and the controller copper busbar is provided on an insulating seat, and the insulating seat is provided on an end cover;

[0006] The end cover is provided with a first end cover oil circuit, the insulating seat is provided with a first insulating seat oil circuit and a second insulating seat oil circuit, and the overlapping portion is provided with a drainage channel; one end of the first insulating seat oil circuit is connected to the first end cover oil circuit, and the other end is connected to the drainage channel; one end of the second insulating seat oil circuit is connected to the drainage channel, and the other end is directed toward the motor copper part; the cooling oil in the first end cover oil circuit flows through the first insulating seat oil circuit to the drainage channel at the overlapping portion, and then flows back to the insulating seat through the second insulating seat oil circuit, and is sprayed toward the first section of the motor copper part, thereby cooling the insulating seat, the motor copper busbar and / or the controller copper busbar, and then flows to the winding by gravity to cool the winding.

[0007] Preferably, at the overlapping portion, the motor copper busbar is arranged on the controller copper busbar, and the lower surface of the controller copper busbar is in contact with the upper surface of the insulating seat; the drainage channel is arranged on the controller copper busbar; the cooling oil in the first end cover oil circuit flows to the controller copper busbar through the first insulating seat oil circuit, and then flows back to the insulating seat through the second insulating seat oil circuit, and is sprayed toward the motor copper parts, thereby cooling the insulating seat, the motor copper busbar and the controller copper busbar.

[0008] Preferably, the drainage channel is provided on the lower surface of the controller copper busbar.

[0009] Preferably, the insulating seat is provided with an oil collecting groove at the overlapping portion, and the first insulating seat oil circuit is connected with the drainage channel through the oil collecting groove.

[0010] Preferably, a sealing ring is provided around the circumference of the oil collecting tank.

[0011] Preferably, the oil collecting tank is rectangular or circular.

[0012] Preferably, the first insulating seat oil circuit includes a main circuit and several branches connected to the main circuit, and the branches lead to each of the oil collecting tanks respectively; each of the overlapping parts is provided with a drainage channel, and each of the drainage channels is connected to a second insulating seat oil circuit respectively, and is sprayed to each of the motor copper parts respectively through the second insulating seat oil circuit.

[0013] Preferably, it also includes a second end cover oil circuit, which is distributed on the end cover along the radial cross-section of the motor and is arranged above the placement position relative to the oil cooling system; the second end cover oil circuit is provided with a plurality of axial oil spray channels, and the oil spray channels are directed toward the winding; the cooling oil in the second end cover oil circuit is sprayed to the winding through the plurality of oil spray channels, and then flows to other parts of the winding by gravity.

[0014] Preferably, it also includes a motor housing, which is connected to the end cover; an axial housing oil circuit is provided on the motor housing, and the first end cover oil circuit and the second end cover oil circuit are connected to the housing oil circuit; a part of the cooling oil in the housing oil circuit flows into the first end cover oil circuit, and the other part flows into the second end cover oil circuit.

[0015] Preferably, a plurality of bumps are provided on the upper surface of the drainage channel.

[0016] Compared with the existing technology, the above technical solution has the following beneficial effects:

[0017] 1. The present invention directs cooling oil to the insulating seat of the copper busbar through the oil passage on the end cap, thereby cooling the insulating seat. Furthermore, the cooling oil in the oil collecting tank of the insulating seat is drained to the copper component through the drainage channel at the overlapped portion, thereby directly cooling the copper component and continuously refreshing the oil in the oil collecting tank. Furthermore, the oil passage on the insulating seat is directed toward the bent portion of the motor copper busbar, thereby further cooling the copper busbar, thereby preventing failure. Furthermore, the required copper busbar thickness can be reduced, thereby achieving the purpose of reducing costs.

[0018] 2. When the electric drive axle is placed normally, the terminal block is on the upper part of the electric drive axle. Therefore, due to gravity, the cooling oil sprayed on the copper bar can directly fall onto the motor windings, thereby cooling the windings without adding other cooling parts;

[0019] 3. The oil collecting tank is provided on the upper surface of the insulating seat, so as to directly cool the bottom surface of the overlapping part (the motor copper busbar or the controller copper busbar);

[0020] 4. Cooling oil can be directly sprayed onto the winding through the several oil spray channels on the second end cover oil circuit. Due to gravity, the cooling oil will flow to other parts of the winding, thereby achieving comprehensive cooling of the winding. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A front view of the oil cooling system of the electric drive axle provided by the present invention;

[0022] Figure 2 A schematic diagram of the oil circuit in the insulating seat provided by the present invention;

[0023] Figure 3 A schematic diagram of the end cover oil circuit provided by the present invention;

[0024] Figure 4 A schematic diagram of the three branches and main circuit of the first insulating seat oil circuit leading to the three-phase copper busbar in the insulating seat provided by the present invention;

[0025] Figure 5 A schematic diagram of the spraying direction of the cooling oil in the oil circuit of the second insulating seat provided by the present invention toward the copper parts of the motor;

[0026] Figure 6 A schematic structural diagram of the second end cover oil circuit provided by the present invention;

[0027] Figure 7 This is a schematic diagram of the distribution of cooling oil in the second insulating seat oil circuit and the second end cover oil circuit due to gravity provided by the present invention.

[0028] Among them: 1-motor end cover, 2-controller copper busbar, 3-motor copper busbar, 4-controller copper parts, 5-motor copper parts, 501-first section, 502-second section, 6-insulating seat, 7-oil collecting tank, 8-drainage channel, 9-second insulating seat oil circuit, 10-motor housing, 11-housing oil circuit, 12-first end cover oil circuit, 13-first insulating seat oil circuit, 14-sealing ring, 15-second end cover oil circuit, 16-oil injection channel. DETAILED DESCRIPTION

[0029] The advantages of the present invention are further described below with reference to the accompanying drawings and specific embodiments.

[0030] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible embodiments consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

[0031] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. As used in this disclosure and the appended claims, the singular forms "a," "an," "the," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0032] It should be understood that although the terms first, second, third, etc. may be used in this disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of this disclosure, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining."

[0033] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0034] In the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the internal communication between two components. It can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances.

[0035] In the following description, the suffixes such as "module", "component" or "unit" used to represent elements are only used to facilitate the description of the present invention and have no specific meaning. Therefore, "module" and "component" can be used interchangeably.

[0036] See attached Figure 1-2 The electric drive bridge includes a motor and a motor controller. The motor includes a motor copper busbar. The motor controller includes a controller copper busbar. The motor copper busbar is connected to the controller copper busbar, thereby electrically connecting the motor and the motor controller.

[0037] The present invention discloses an oil cooling system for an electric drive axle. Typically, the motor copper busbar and the controller copper busbar are both three-phase copper busbars with three copper parts. The motor copper busbar includes three motor copper parts, and the controller copper busbar includes three controller copper parts. The first section of the motor copper part is bent and connected to the motor, and the second section (at the other end) overlaps with one end of the controller copper part, thereby connecting the motor copper busbar to the controller copper busbar, thereby electrically connecting the motor and the motor controller. Similarly, one end of the controller copper part is bent and connected to the controller, and the other end is connected to the motor copper part. The overlapping portion of the motor copper busbar and the controller copper busbar is provided on an insulating seat, and the insulating seat is provided on an end cover.

[0038] It should be noted that the motor copper component of the present invention can be understood as consisting of a first section and a second section. The first section is the bent section, the second section is the section that overlaps with the controller copper component, and the portion other than the first section is the second section. Although the portion other than the first section does not entirely overlap with the controller copper component, it can be considered to be used for overlapping with the controller copper component.

[0039] A first end cover oil circuit is provided on the motor end cover, which is connected to the insulating seat and is used to introduce the cooling oil in the motor end cover into the insulating seat; and a first insulating seat oil circuit and a second insulating seat oil circuit are provided on the insulating seat. The first insulating seat oil circuit can be regarded as the oil inlet circuit of the insulating seat, and the second insulating seat oil circuit can be regarded as the oil outlet circuit of the insulating seat. The oil outlet circuit is used to spray cooling oil to the first section of the motor copper part.

[0040] The first insulating seat oil circuit and the second insulating seat oil circuit are connected through a drainage channel, which is arranged at the overlapping part of the motor copper part and the controller copper part. When the controller copper part contacts the insulating seat, the drainage channel is arranged on the controller copper part. When the motor copper part contacts the insulating seat, the drainage channel is arranged on the motor copper part.

[0041] Specifically, one end of the first insulating seat oil circuit is connected to the first end cover oil circuit, and the other end is connected to the drainage channel; one end of the second insulating seat oil circuit is connected to the drainage channel, and the other end is directed toward the first section of the motor copper part. The cooling oil in the first end cover oil circuit flows through the first insulating seat oil circuit to the drainage channel at the overlap, and then flows back to the insulating seat through the second insulating seat oil circuit and sprayed toward the first section of the motor copper part, thereby cooling the insulating seat, motor copper busbar, and / or controller copper busbar. See attached. Figure 7 , and then flows to the winding by gravity to cool the winding.

[0042] See attached Figure 3 The first end cover oil circuit includes an axial first section and a radial second section (not a standard radial section, but distributed along a radial cross section), thereby delivering the oil in the end cover to the surface of the insulating seat. Then, the first insulating seat oil circuit includes a radial first section (not a standard radial section, but distributed along a radial cross section), thereby delivering the oil to the inside of the insulating seat. (See attached Figure 4 ) and then upwards to the copper busbar.

[0043] The present invention preferably makes the controller copper part contact with the insulating seat, and the drainage channel is provided on the controller copper part. When the coolant flows into the insulating seat and then sprays from the insulating seat to the motor copper part, the insulating seat, the controller copper part and the motor copper part are cooled at the same time.

[0044] See attached Figure 2 At the overlap, the motor busbar is mounted on the controller busbar, with its lower surface in contact with the upper surface of the insulating base. A drainage channel is provided on the controller busbar, specifically on its lower surface. Cooling oil in the first end cap oil circuit flows through the first insulating base oil circuit to the controller busbar, then back through the second insulating base oil circuit to the insulating base and sprayed onto the motor copper components, thereby cooling the insulating base, motor busbar, and controller busbar.

[0045] Preferably, an oil collecting groove is provided at the overlapped portion of the insulating seat, and the first insulating seat oil circuit is connected to the drainage channel through the oil collecting groove. The cooling oil is collected in the oil collecting groove, which can cool the insulating seat and the back of the controller copper busbar.

[0046] The oil collecting tank can be rectangular or circular, and the sizes of the oil collecting tanks at the three copper parts are not consistent. They can be set according to the size of the copper parts at the overlap. See the attached Figure 1The rightmost copper piece has the largest size at the overlap, so the oil collecting tank under the copper piece can be set to the largest. Similarly, the leftmost copper piece has the smallest size at the overlap, so the oil collecting tank under the copper piece can be set to the smallest.

[0047] Preferably, a sealing ring is provided around the oil collecting tank to prevent leakage of oil in the oil collecting tank.

[0048] Better, see attached Figure 2 、 4 -5. The first insulating base oil circuit includes a main circuit and three branch circuits connected to the main circuit, each of which leads to each oil sump. A drainage channel is provided at each overlap (i.e., the junction between the controller copper component and the motor copper component. In this preferred embodiment, the controller copper component is located below the motor copper component and connected to the insulating base, so that the drainage channel is provided on the controller copper component). Each drainage channel is connected to a second insulating base oil circuit, and oil is sprayed through the second insulating base oil circuit to each motor copper component.

[0049] The insulating seat is fixed to the motor end cover by bolts, so that the oil channel in the insulating seat is connected with the oil channel of the end cover.

[0050] Better, see attached Figure 6-7 The motor also includes a second end cap oil circuit, which is distributed along the radial cross-section of the motor and located above the oil cooling system. The second end cap oil circuit is provided with a plurality of axial oil injection channels, which face the windings. If the end cap is relatively thin, these oil injection channels can be considered oil injection holes. If the end cap is relatively thick, these oil injection channels are axial oil passages, which are through-holes facing the windings.

[0051] The cooling oil in the second end cover oil circuit is sprayed to the winding through several oil spray channels to cool it. Later, since the second end cover oil circuit is above the position relative to the oil cooling system, the winding directly sprayed by the oil spray channel is also above the position relative to the oil cooling system. Therefore, it can flow to other parts of the winding by gravity, thereby realizing comprehensive cooling of the winding.

[0052] Better, see the attached Figure 2 , further comprising a motor housing connected to the end caps. An axial housing oil circuit is provided in the motor housing, with the first and second end cap oil circuits communicating with the housing oil circuit (in practice, this can be considered to be a main circuit on the end caps, which directly connects to the housing oil circuit, and then to the first and second end cap oil circuits, respectively). This allows a portion of the cooling oil in the housing oil circuit to flow into the first end cap oil circuit and another portion to flow into the second end cap oil circuit.

[0053] Preferably, the insulating seat and the copper busbar are covered with plastic to prevent the copper busbar and the insulating seat from being damaged due to excessive temperature and causing assembly failure.

[0054] Preferably, the upper surface of the drainage channel is provided with a plurality of bumps, which can be used to increase the contact area between the cooling oil and the copper part of the control component and enhance the cooling effect. The bumps can be rectangular or circular.

[0055] It should be noted that the embodiments of the present invention have better practicability and do not impose any form of limitation on the present invention. Any technician familiar with the field may use the technical content disclosed above to change or modify it into an equivalent effective embodiment. However, any modification or equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. An oil cooling system for an electric drive axle, comprising a motor copper busbar and a controller copper busbar of a motor controller; the motor copper busbar comprises a plurality of motor copper parts, and the controller copper busbar comprises a plurality of controller copper parts, wherein a first section of the motor copper part is bent and connected to the motor, and a second section overlaps with one end of the controller copper part, thereby connecting the motor copper busbar to the controller copper busbar, thereby electrically connecting the motor and the motor controller, characterized in that: The overlapping portion of the motor copper busbar and the controller copper busbar is arranged on an insulating seat, and the insulating seat is arranged on an end cover; The end cap is provided with a first end cap oil circuit, the insulating seat is provided with a first insulating seat oil circuit and a second insulating seat oil circuit, and a drainage channel is provided at the overlapped portion; one end of the first insulating seat oil circuit is connected to the first end cap oil circuit, and the other end is connected to the drainage channel; one end of the second insulating seat oil circuit is connected to the drainage channel, and the other end faces the first section of the motor copper part; The cooling oil in the first end cover oil circuit flows through the first insulating seat oil circuit to the drainage channel at the overlapped portion, then flows back to the insulating seat through the second insulating seat oil circuit and sprays toward the motor copper parts, thereby cooling the insulating seat, the motor copper busbar, and / or the controller copper busbar, and then flows to the winding by gravity to cool the winding; The insulating seat is provided with an oil collecting groove at the overlapping portion, and the first insulating seat oil circuit is communicated with the drainage channel through the oil collecting groove.

2. The oil cooling system according to claim 1, characterized in that: At the overlapping portion, the motor copper busbar is arranged on the controller copper busbar, and the lower surface of the controller copper busbar contacts the upper surface of the insulating seat; The drainage channel is provided on the controller copper busbar; The cooling oil in the first end cover oil circuit flows to the controller copper busbar through the first insulating seat oil circuit, then flows back to the insulating seat through the second insulating seat oil circuit, and sprays toward the motor copper parts, thereby cooling the insulating seat, the motor copper busbar and the controller copper busbar.

3. The oil cooling system according to claim 2, characterized in that: The drainage channel is arranged on the lower surface of the controller copper busbar.

4. The oil cooling system according to claim 1, characterized in that: A sealing ring is provided around the circumference of the oil collecting groove.

5. The oil cooling system according to claim 1, characterized in that: The oil collecting tank is rectangular or circular.

6. The oil cooling system according to claim 1, characterized in that: The first insulating seat oil circuit includes a main circuit and a plurality of branch circuits connected to the main circuit, and the branch circuits lead to each of the oil collecting tanks respectively; Each overlapping portion is provided with a drainage channel, and each drainage channel is respectively connected to a second insulating seat oil circuit, and is sprayed toward each motor copper part through the second insulating seat oil circuit.

7. The oil cooling system according to claim 1, characterized in that: It also includes a second end cover oil circuit, which is distributed on the end cover along the radial cross section of the motor and is arranged above the position relative to the oil cooling system; The second end cover oil circuit is provided with a plurality of axial oil injection channels, and the oil injection channels face the winding; The cooling oil in the oil circuit of the second end cover is sprayed to the winding through the plurality of oil spray channels, and then flows to other parts of the winding by gravity.

8. The oil cooling system according to claim 7, characterized in that: Also included is a motor housing, wherein the motor housing is connected to the end cover; The motor housing is provided with an axial housing oil circuit, and the first end cover oil circuit and the second end cover oil circuit are connected to the housing oil circuit; A portion of the cooling oil in the housing oil passage flows into the first end cover oil passage, and another portion flows into the second end cover oil passage.

9. The oil cooling system according to claim 1, characterized in that: A plurality of protrusions are provided on the upper surface of the drainage channel.

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