CN221009901U

CN221009901U - Motor and vehicle power system

Info

Publication number: CN221009901U
Application number: CN202322397756.1U
Authority: CN
Inventors: 殷庆振; 刘磊
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2023-09-05
Filing date: 2023-09-05
Publication date: 2024-05-24
Anticipated expiration: 2033-09-05

Abstract

The application proposes an electric motor and a vehicle power system, the electric motor comprising: -a housing (1), said housing (1) comprising a housing body (11) and a housing lip (12), said housing lip (12) being connected to said housing body (11); an end cap (2), the end cap (2) comprising an end cap body (21) and an end cap lip (22), the end cap lip (22) being connected to the end cap body (21), the housing body (11) and the end cap body (21) being connected together to form a cavity; a stator (3), the stator (3) comprising a stator core (31) and a stator winding (32); and a rotor (4), the rotor (4) being located radially inward of the stator (3), neither the casing lip (12) nor the end cap lip (22) being provided with an oil hole for flowing the coolant to the rotor (4).

Description

Motor and vehicle power system

Technical Field

The application belongs to the technical field of vehicles, and particularly relates to a motor and a vehicle power system.

Background

CN110492663a discloses a motor, a power assembly and an automobile, wherein an oil ring is arranged in the motor, the oil ring is provided with a through hole, and cooling oil can flow to a rotor bearing through the through hole, so that the rotor bearing is cooled.

The utility model patent CN212649253U discloses a motor oil cooling device, a motor assembly and a vehicle, wherein the motor oil cooling device comprises a shell and a stator arranged in the shell; the stator comprises a stator core and a stator winding wound on the inner wall of the stator core; the shell is provided with a shell cooling channel, two ends of the shell cooling channel extend to two end parts of the winding respectively, and an oil spraying ring for guiding cooling oil to spray to the winding end parts is arranged between the shell cooling channel and the winding end parts. The cooling oil is sprayed or dropped through the oil holes at the stator winding ends, and then the cooling oil can flow to rotor-related components such as the rotor lamination, the rotor shaft, and the bearing.

The drawbacks of the above prior art include:

(1) The required cooling oil quantity is more, and the cost is high.

(2) The need to provide a special oil ring, which is usually made of plastic material, is easily deformed after long-time hot corrosion and oil corrosion, and causes leakage, which results in reduced reliability and increased cost.

(3) The highest temperature position of the motor is the middle part of the winding instead of the winding ends, and the cooling oil cannot directly contact the middle part of the winding, resulting in poor cooling effect.

(4) Both the stator and the rotor are in contact with cooling oil, and during the high-speed rotation of the rotor, the friction between the rotor and the oil can cause additional energy loss, which affects the efficiency of the motor.

(5) Since the rotor is in contact with the cooling oil, a dynamic seal needs to be provided, which results in a complicated sealing structure.

Disclosure of utility model

The present application aims to propose an electric machine that solves or alleviates at least one of the drawbacks of the prior art described above. The application also provides a vehicle power system comprising the motor.

An embodiment of the present application proposes a motor including:

A housing comprising a housing body and a housing lip, the housing lip being connected to the housing body;

The end cover comprises an end cover main body and an end cover lip, wherein the end cover lip is connected with the end cover main body, and the shell main body and the end cover main body are connected together to form a cavity;

a stator including a stator core and a stator winding; and

A rotor located radially inward of the stator,

A first accommodation space is defined on one axial side of the stator core and on the radial outer side of the rotor, the shell lip is abutted against one axial end of the stator core, the shell lip separates the first accommodation space from the rotor,

A second accommodation space is defined on the other axial side of the stator core and the radial outer side of the rotor, the end cover lip part is abutted against the other axial end of the stator core, the end cover lip part separates the second accommodation space from the rotor,

The stator core is provided with a plurality of runner grooves penetrating the stator core in an axial direction of the motor, winding end portions of the stator winding protruding from the stator core are immersed in a cooling liquid in the first accommodation space and the second accommodation space, the cooling liquid is capable of passing through the runner grooves from the first accommodation space to the second accommodation space,

Neither the casing lip nor the end cap lip is provided with an oil hole for flowing the coolant to the rotor.

In at least one possible embodiment, a sealing ring is provided between the housing lip and the stator core, and

And a sealing ring is arranged between the end cover lip and the stator core.

In at least one possible embodiment, the housing body and the housing lip are integrally formed, and

The end cap body and the end cap lip are integrally formed.

In at least one possible embodiment, the motor further comprises a rotor shaft fixedly connected to the rotor shaft, heat of the rotor being conducted through the rotor shaft to the housing and the end cap, the rotor not being immersed in cooling oil.

In at least one possible embodiment, the stator core is provided with a stator winding mounting groove penetrating through the stator core in an axial direction of the motor, the stator winding is mounted in the stator winding mounting groove, and an inner wall of the stator winding mounting groove is provided with a plurality of runner grooves.

In at least one possible embodiment, the plurality of runner grooves decrease in circumferential dimension in sequence in a direction pointing radially inward from a radially outer side of the motor.

In at least one possible embodiment, the stator winding comprises wires, each of which corresponds to at least one of the runner slots,

The flow channel groove is arranged on one side or two sides of the lead wire in the circumferential direction of the stator core.

In at least one possible embodiment, the flow channel groove is semicircular in cross section.

In at least one possible embodiment, the stator winding mounting groove is provided with an opening in an inner circumference of the stator core, the opening being provided with a winding mounting groove wedge that extends the inner circumference of the stator core continuously over the entire circumference.

The embodiment of the application also provides a vehicle power system, which comprises the motor in any one of the technical schemes.

By adopting the technical scheme, the motor and the vehicle power system can obtain at least one of the following beneficial effects.

(1) Neither the casing lip nor the end cap lip is provided with oil holes for flowing cooling fluid (e.g., cooling oil) from the first accommodation space and the second accommodation space to the rotor, and cooling of the motor stator and the motor rotor can be performed separately without affecting each other.

The stator is cooled by using the cooling liquid, the winding end is immersed in the cooling liquid in the first accommodating space and the second accommodating space, the required cooling liquid amount is small, and the cooling effect is good.

(2) The sealing mode of the shell lip and the end cover lip is static sealing, the structure is simple, the cost is low, the sealing effect is good, and the leakage of cooling liquid is not easy to occur.

(3) The shell lip and the end cover lip can be made of metal through casting, and are not easy to deform after long-time hot corrosion and oil corrosion, so that the cooling liquid is not easy to leak.

(4) The rotor is not cooled by the cooling liquid, so that energy loss caused by contact between the rotor and the cooling liquid is avoided, and the motor efficiency is high.

(5) The stator winding is immersed in the cooling liquid, so that the cooling efficiency is high.

Drawings

Fig. 1 shows a schematic configuration of a vehicle power system according to an embodiment of the present application.

Fig. 2 shows a schematic structural view of a housing and an end cover of an electric motor of a vehicle powertrain according to an embodiment of the present application.

Fig. 3 shows a schematic structural view of a housing of a motor of a vehicle power system according to an embodiment of the present application.

Fig. 4 shows a schematic structural view of an end cover of an electric motor of a vehicle power system according to an embodiment of the present application.

Fig. 5 shows a schematic structural view of a stator of an electric motor of a vehicle power system according to an embodiment of the present application.

Fig. 6 shows a partial enlarged view of a stator of a motor of a vehicle power system according to an embodiment of the present application.

Fig. 7 shows a partial cross-sectional view of a stator of an electric machine of a vehicle powertrain according to an embodiment of the present application.

Description of the reference numerals

100 Motor 200 gearbox

1 Shell 11 Shell Main body 12 Shell lip 13 Shell lip Reinforcement

2 End cover 21 end cover main body 22 end cover lip 23 end cover lip reinforcing rib

3 Stator 31 stator core 32 stator winding 33 runner groove 34 winding installation slot wedge block

4. Rotor

5. Sealing ring

Aaxial C circumferential R radial

Detailed Description

To more clearly illustrate the above objects, features and advantages of the present application, specific embodiments of the present application are described in detail in this section with reference to the accompanying drawings. The present application can be embodied in various forms other than those described in this section, and modifications, variations, and alternatives thereto can be made by those skilled in the art without departing from the spirit of the application, and therefore the application is not limited to the specific examples disclosed in this section. The protection scope of the present application shall be subject to the claims.

As shown in fig. 1 to 7, an embodiment of the present application proposes a vehicle power system including a motor 100 and a transmission 200, the transmission 200 may include a plurality of gears, and the transmission 200 may be used to change the rotational speed/torque or the like output from the motor 100 and/or to change the rotational speed/torque or the like input to the motor 100. The vehicle power system may be used for a pure electric vehicle or a hybrid vehicle, etc. As an example, the transmission 200 may be connected to wheels or the like.

The motor 100 includes a housing 1, an end cap 2, a stator 3, and a rotor 4. The housing 1 and the end cap 2 may be connected together to form a cylindrical cavity, and the housing 1 of the motor may also serve as part of the housing of the gearbox 200. The stator 3 and the rotor 4 are disposed in the cavity, the rotor 4 is rotatably mounted to the housing 1 with respect to the housing 1, and the stator 3 may be located radially outside the rotor 4.

The axial one end (right end of fig. 1) of the housing 1 may be provided with a cooling oil inlet, the axial other end (left end of fig. 1) of the housing 1 or the end cap 2 may be provided with a cooling oil outlet, and the cooling oil may flow from one end of the cavity to the other end of the cavity, thereby cooling the stator 3 of the motor 100.

As shown in fig. 1 to 3, the case 1 includes a case body 11 and a case lip 12, the case body 11 may be cylindrical, the case lip 12 may be provided radially inward of the case body 11, and the case lip 12 may extend in an axial direction a from an end surface of one side in an axial direction of the case body 11. The casing lip 12 is located radially inward of winding ends of the stator windings 32 protruding from the stator core 31 (see fig. 5), a free end of the casing lip 12 away from the base may abut against the stator core 31 of the stator 3, a seal ring 5 may be provided between the casing lip 12 and the stator core 31, and the seal ring 5 may prevent cooling oil from leaking radially inward of the casing lip 12, avoiding the cooling oil from contacting the rotor 4. The sealing mode of the sealing ring 5 is static sealing, the structure is simple, the cost is low, the sealing effect is good, and the leakage of cooling oil is not easy to occur. The housing lip 12 may be provided with a groove to accommodate the sealing ring 5, and the sealing ring 5 may be an O-ring.

Housing body 11 and housing lip 12 may each be made of metal, and housing body 11 and housing lip 12 may be integrally formed, such as by casting. The casing lip 12 is also less prone to deformation after long periods of hot and oil corrosion, which makes the cooling oil less prone to leakage, and the reliability of the motor 100 is higher, saving the cost of repairing cooling oil leakage failure and the cost of specially making an independent oil ring.

The radially inner side and/or the radially outer side of the casing lip 12 may be provided with a plurality of casing lip reinforcing ribs 13, and the plurality of casing lip reinforcing ribs 13 may be arranged radially.

As shown in fig. 1, 2 and 4, the end cap 2 includes an end cap body 21 and an end cap lip 22, and the end cap body 21 may be plate-shaped, and the case body 11 and the end cap body 21 are coupled together to form a cavity. The end cap lip 22 may extend in the axial direction a from the housing body 11. The end cover lip 22 is located radially inward of the winding end of the stator winding 32, the free end of the end cover lip 22 away from the base may abut against the stator core 31 of the stator 3, a seal ring 5 may be provided between the end cover lip 22 and the stator core 31, and the seal ring 5 may prevent cooling oil from leaking radially inward of the end cover lip 22, avoiding the cooling oil from contacting the rotor 4. The sealing mode of the sealing ring 5 is static sealing, the structure is simple, the cost is low, the sealing effect is good, and the leakage of cooling oil is not easy to occur. The end cap lip 22 may be provided with a groove to receive the seal ring 5, and the seal ring 5 may be an O-ring.

The end cap body 21 and the end cap lip 22 may be both made of metal, and the end cap body 21 and the end cap lip 22 may be integrally formed by, for example, casting. The end cap lip 22 is also less prone to deformation after long periods of hot and oil corrosion, which makes the cooling oil less prone to leakage, and the reliability of the motor 100 is higher, saving the cost of repairing cooling oil leakage failure and the cost of specially making an independent oil ring.

The radially inner side and/or the radially outer side of the end cap lip 22 may be provided with a plurality of end cap lip reinforcing ribs 23, and the plurality of end cap lip reinforcing ribs 23 may be arranged radially.

As shown in fig. 1, 5 to 7, the stator 3 includes a stator core 31 and stator windings 32, the stator core 31 may be cylindrical, the stator core 31 is provided with stator winding mounting grooves penetrating the stator core 31 in the axial direction a of the motor, and the stator winding mounting grooves may be provided in plurality in the circumferential direction C of the stator core 31. The stator winding 32 is mounted in the stator winding mounting groove, and a part of the stator winding 32 (a middle portion of the stator winding 32) is fitted into the stator winding mounting groove, and the stator winding 32 may be exposed from both ends in the axial direction a of the stator core 31, and the exposed part may be referred to as a winding end portion.

The case body 11, the case lip 12, and the stator core 31 define a first accommodation space S1 on one axial side (right side in fig. 1) of the stator core 31 and on the radially outer side of the rotor 4, the case lip 12 abuts on one axial end of the stator core 31, and the case lip 12 partitions the first accommodation space S1 and the rotor 4.

The housing body 11, the end cap body 21, the end cap lip 22, and the stator core 31 define a second accommodation space S2 on the other axial side (left side in fig. 1) of the stator core 31 and the radially outer side of the rotor 4, the end cap lip 22 abuts the other axial end of the stator core 31, and the end cap lip 22 partitions the second accommodation space S2 from the rotor 4. The cooling oil in the first accommodating space S1 and the second accommodating space S2 cannot leak to the rotor 4, so that energy loss caused by contact between the rotor 4 and the cooling oil is avoided, and the motor efficiency is high.

The motor 100 may be a hairpin motor and the stator windings 32 may be hairpin windings formed of flat copper wire. Referring to fig. 7, the stator winding mounting groove may be provided with an opening at an inner circumference of the stator core 31. The opening is provided with a winding installation groove wedge 34, the winding installation groove wedge 34 can be sealed and installed with the opening, the winding installation groove wedge 34 can enable the inner peripheral surface of the stator core 31 to continuously extend along the whole circumference, the shell lip 12 and the end cover lip 22 can be abutted against the winding installation groove wedge 34, and cooling oil cannot leak from the radial inner side of the stator winding installation groove.

The motor further comprises a rotor shaft to which the rotor 4 may be fixedly connected, neither the casing lip 12 nor the end cap lip 22 being provided with oil holes for letting the coolant flow to the rotor 4, the rotor 4 not being immersed in the cooling oil, and the heat of the rotor being conducted through the rotor shaft to the casing 1 and the end cap 2, whereby rotor heat dissipation is achieved. The stator is cooled with a coolant, in which the winding heads are immersed in the first accommodation space S1 and the second accommodation space S2, and the rotor is not cooled with a coolant, so that the amount of coolant required is small and the cooling effect is good. The cooling of the motor stator and the motor rotor can be carried out separately without mutual influence.

The stator winding 32 may include wires such as copper wires and insulating paper surrounding the wires. The insulating paper may insulate the wires from stator core 31 and/or the multiphase wires.

As shown in fig. 6 and 7, the inner wall of the stator winding mounting groove is provided with a flow path groove 33, and the flow path groove 33 penetrates the stator core 31 in the axial direction a of the stator core 31, so that the first accommodation space S1 and the second accommodation space S2 communicate with each other through the flow path groove 33. The flow path grooves 33 may be located at opposite sides of the stator winding mounting groove in the circumferential direction C of the stator core 31.

In a state where the stator winding 32 is mounted on the stator core 31, the inner wall of the stator winding mounting groove and the stator winding 32 enclose a cooling flow passage (flow passage groove 33) extending in the axial direction a of the stator 3. The runner grooves 33 are located on both sides of the wires in the circumferential direction C of the stator core 31, and each side may be provided with a plurality of runner grooves 33 arranged in the radial direction R, so that each wire of the stator winding 32 corresponds to at least one runner groove 33, and thus the cooling effect of the cooling oil on the stator winding 32 is good.

The stator winding 32 is the most part that generates heat of stator 3, and the cooling runner that runner groove 33 formed is used for through the cooling oil, and the cooling oil can directly cool stator winding 32 through runner groove 33, and the cooling effect is better. The runner slots 33 do not occupy the radial space of the stator core 31, which makes the motor 100 compact and small in size.

As shown in fig. 7, the radial dimension and the circumferential dimension (cross-sectional area) of the plurality of runner grooves 33 may be sequentially reduced in a direction from the radially outer side toward the radially inner side of the motor. This makes it possible to make the circumferential dimensions of the portions of the stator core 31 between two adjacent sets of stator windings 32 in the circumferential direction C identical (including substantially identical) throughout the radial direction R. For example, in the radial direction R of the stator core 31, the circumferential dimension of the stator core 31 between adjacent runner grooves 33 located at the radially outer side is C1, the circumferential dimension of the stator core 31 between adjacent runner grooves 33 located at the radially middle position is C2, and the circumferential dimension of the stator core 31 between adjacent runner grooves 33 located at the radially inner side is C3. C1, C2 and C3 are the same (including about the same) size. This allows the stator 3 to still have a sufficient flux area in the radially inner portion so that the performance of the motor is not impaired.

The cross section of the flow channel groove 33 may be various shapes such as a semicircle, a rectangle, a trapezoid, and the like. Alternatively, the cross section of the flow channel groove 33 may be, for example, semicircular, and the semicircular flow channel groove 33 may make the stress distribution uniform. The stator core 31 includes a plurality (e.g., hundreds) of laminations, the laminations having the stator winding mounting slots and the runner slots 33 can be formed by stamping the laminations, and the runner slots 33 are easy to machine.

It will be appreciated that the semicircle here need not be exactly half of a circle, including a few semicircle or a plurality of semicircles. That is, here, a circle is cut along a straight line parallel to one diameter of the circle, and a portion separated from the circle is referred to as a semicircle.

The flow process of the cooling oil is described below with reference to fig. 1, and the unidirectional arrow in fig. 1 indicates the flow direction of the cooling oil.

The cooling oil may enter the first accommodation space S1 from the liquid inlet, and then the cooling oil may flow in the axial direction a in the cooling flow passage formed by the flow passage groove 33, cooling the stator 3 of the motor. The cooling oil can contact the stator winding 32 and flow from the inside of the stator core 31 through the flow direction to the second accommodation space S2, and finally the cooling liquid is discharged from the liquid discharge port to the second accommodation space S2. The winding end portions of the stator winding 32 may be immersed in the cooling oil of the first and second accommodation spaces S1 and S2, and the middle portion of the stator winding 32 may be immersed in the cooling oil of the flow path groove 33. Thus, the stator winding 32 and the stator core 31 are cooled well, and the motor can be made compact. The stator 3 dissipates heat by cooling oil, and the rotor 4 dissipates heat by conducting heat to the housing 1 and the end cap 2. In one example of the present application, the rotor 4 is not immersed in the cooling oil, and the rotor 4 does not suffer from a problem such as a loss of power due to stirring of the cooling oil.

It will be appreciated that although a vehicle powertrain including an electric machine and a transmission is shown in the drawings, the application is not so limited. The above-described stator cooling structures, features, concepts, etc. of the present application may also be used with motors that are not connected to a gearbox or housed in the same housing.

The motor and the vehicle power system of the application have the following beneficial effects.

(1) The seal between the shell lip 12 and the end cap lip 22 is static, and has the advantages of simple structure, low cost, good sealing effect and difficult occurrence of cooling oil leakage.

(2) The shell lip 12 and the end cap lip 22 may be cast from metal and are not easily deformed after long periods of hot and oil corrosion, making the cooling oil less prone to leakage.

(3) The rotor is not cooled by the cooling oil, so that energy loss caused by contact between the rotor and the cooling oil is avoided, and the motor efficiency is high.

(4) The stator winding 32 is immersed in the cooling oil, and the cooling efficiency is high.

It is to be understood that at least some aspects or features of the above-described implementations, embodiments or examples may be combined as appropriate.

It is to be understood that in the present application, when the number of parts or members is not particularly limited, the number may be one or more, and the number herein refers to two or more. For the case where the number of parts or members is shown in the drawings and/or described in the specification as a specific number such as two, three, four, etc., the specific number is generally illustrative and not restrictive, it can be understood that a plurality, i.e., two or more, is plural, but this does not mean that the present application excludes one.

In the present application, unless explicitly stated or limited otherwise, terms such as "mounted," "assembled," "connected," "coupled," "joined," "abutting," "communicating," "conducting," "fixed," "fastened," and the like are to be construed broadly, as they may be, for example, direct or indirect. For example, the connection may be a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other, or may interact with each other, unless explicitly stated or limited otherwise. For example, the communication/conduction may be direct communication/conduction or indirect communication/conduction via an intermediate medium. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present application, unless explicitly stated or defined otherwise, one member is provided/mounted/located/accommodated/placed in/within another member, inside, etc., may be either of the following two cases: a portion or a majority of the one member is located within the other member; and the one member is fully received within the other member.

While the present application has been described in detail using the above embodiments, it will be apparent to those skilled in the art that the present application is not limited to the embodiments described in the present specification. The present application can be modified and implemented as modified embodiments without departing from the spirit and scope of the present application as defined by the claims. Accordingly, the descriptions in this specification are for the purpose of illustration and are not intended to be limiting in any way.

Claims

1. An electric machine, comprising:

a stator including a stator core and a stator winding; and

A rotor located radially inward of the stator,

2. The electric machine of claim 1, wherein a seal ring is provided between the housing lip and the stator core, and

And a sealing ring is arranged between the end cover lip and the stator core.

3. The electric machine of claim 1, wherein the housing body and the housing lip are integrally formed, and

The end cap body and the end cap lip are integrally formed.

4. The electric machine of claim 1, further comprising a rotor shaft fixedly connected to the rotor shaft through which heat of the rotor is conducted to the housing and the end cap, the rotor not being immersed in cooling oil.

5. The motor according to any one of claims 1 to 4, characterized in that the stator core is provided with a stator winding mounting groove penetrating the stator core in an axial direction of the motor, the stator winding being mounted to the stator winding mounting groove, an inner wall of the stator winding mounting groove being provided with a plurality of runner grooves.

6. The electric machine of claim 5, wherein the plurality of runner grooves sequentially decrease in circumferential dimension in a direction pointing radially inward from a radially outer side of the electric machine.

7. The motor of claim 5 wherein said stator windings include wires, each of said wires corresponding to at least one of said runner slots,

8. The electric machine of claim 5 wherein the flow channel slot is semi-circular in cross-section.

9. The motor of claim 5, wherein the stator winding mounting groove is provided with an opening in an inner circumference of the stator core, the opening being provided with a winding mounting groove wedge that extends the inner circumference of the stator core continuously over the entire circumference.

10. A vehicle powertrain comprising an electric machine as claimed in any one of claims 1 to 9.