CN107134877A - Motor and electric automobile - Google Patents

Abstract

A motor and an electric vehicle, wherein the motor includes a casing and a cooling passage located in the casing, the cooling passage surrounds the central axis of the casing, and a partition is arranged in the cooling passage; the partition The cooling channel is axially partitioned into two sub-channels, the partition member has a connecting channel connecting the two sub-channels, and the two sub-channels respectively have an input port and an output port, and the input port and the output port The ports are all spaced apart from the connecting channel along the circumferential direction. With this technical solution, the first sub-channel and the second sub-channel in the cooling channel are connected through the connecting channel, the coolant in the first sub-channel, the second sub-channel and the connecting channel are all in a continuous flow state, and no dead water zone will be formed . Therefore, the coolant in the entire cooling channel is in a state of continuous flow, which reduces the probability of forming a dead water zone. This can eliminate the problem of local overheating of the motor, reduce power loss, and improve the working efficiency of the motor.

Description

Electric Motors, Electric Vehicles

technical field

The invention relates to a motor and an electric vehicle.

Background technique

Electric vehicles are powered by on-board power supplies, and use electric motors to convert electrical energy into mechanical energy to drive wheels. An existing electric motor for an electric vehicle includes a housing, in which an annular cooling passage is provided around the central axis of the housing, and a coolant can circulate in the cooling passage, and the coolant can absorb the energy of the motor during the circulation process. The generated heat realizes the purpose of cooling the motor.

A partition member is provided in the cooling passage to partition the cooling passage along the circumferential direction. The cooling channel has an input port and an output port, and the input port and the output port are both close to the partition and respectively located on two sides of the partition along the circumferential direction. The low-temperature coolant flows into the cooling channel from the input port and flows in the circumferential direction in the cooling channel. During the flow process, the coolant absorbs heat and becomes a high-temperature coolant, and the high-temperature coolant flows out from the output port. During this process, the partition prevents the low-temperature coolant input from the input port from mixing with the high-temperature coolant at the position of the output port.

However, the existing motor still has the problem of local overheating, which causes power loss and reduces the working efficiency of the motor.

Contents of the invention

The problem solved by the invention is that the existing motor has the problem of partial overheating, which causes power loss and reduces the working efficiency of the motor.

In order to solve the above problems, the present invention provides a motor, the motor includes a housing and a cooling channel located in the housing, the cooling channel surrounds the central axis of the housing, and a partition is provided in the cooling channel; The partition part divides the cooling channel into two sub-channels in the axial direction, the partition part has a connecting channel connecting the two sub-channels, and the two sub-channels respectively have an input port and an output port, the Both the input port and the output port are spaced apart from the connecting channel along the circumferential direction.

Optionally, the axial width of the sub-channel where the input port is located is greater than the axial width of the sub-channel where the output port is located.

Optionally, the axial width of the sub-channel where the input port is located decreases gradually from the input port to the connecting channel in the circumferential direction, and/or the axial width of the sub-channel where the output port is located It gradually decreases from the connecting channel to the output port in the circumferential direction.

Optionally, the axial width of the cooling channel is constant along the circumferential direction, and the axial width of the partition is constant along the circumferential direction.

Optionally, the axial width of the sub-channel where the input port is located at the position of the input port is greater than half of the axial width of the cooling channel.

Optionally, the axial width of each of the sub-channels at the position of the connecting channel is equal to half of the axial width of the cooling channel.

Optionally, both the input port and the output port are separated from the connecting channel by 180° in the circumferential direction.

Optionally, each of the sub-channels is symmetrical with respect to the plane where the input port, the output port and the connecting channel are located.

Optionally, the connecting channel is a notch.

The present invention also provides an electric vehicle, which includes any one of the motors described above.

Compared with the prior art, the technical solution of the present invention has the following advantages:

The first sub-channel and the second sub-channel in the cooling channel are connected through the connecting channel, and the coolant in the first sub-channel, the second sub-channel and the connecting channel are all in a state of continuous flow, and no dead water zone will be formed. Therefore, the coolant in the entire cooling channel is in a state of continuous flow, which reduces the probability of forming a dead water zone. This can eliminate the problem of local overheating of the motor, reduce power loss, and improve the working efficiency of the motor.

Description of drawings

Fig. 1 is a sectional view of a motor installed in an electric vehicle according to a specific embodiment of the present invention;

Fig. 2 is the perspective view of the water jacket in the motor of the specific embodiment of the present invention;

Fig. 3 is a plane view of the water jacket shown in Fig. 2 viewed from the input port and the output port along the radial direction;

Fig. 4 is a plan view of the water jacket shown in Fig. 2 viewed from the connecting channel along the radial direction.

detailed description

Aiming at the problems existing in the prior art, the inventor found through research that the inlet and outlet of the cooling channel are located on both sides of the partition, which forms a dead water zone near the partition between the inlet and the outlet.

During the coolant circulation process, due to the partition, the low-temperature coolant flowing from the input port will flow towards the output port, and only a small amount of low-temperature coolant will flow to the cooling channel area between the partition and the input port, so that The coolant in the area of the cooling channel between the partition and the inlet is in a stagnant state for a long time.

Correspondingly, the low-temperature coolant from the input port flows into the high-temperature coolant after flowing through the cooling channel, and the high-temperature coolant directly flows into the output port and is output, while only a small amount of high-temperature coolant flows to the area between the partition and the output port, making the partition The coolant in the area between the parts and the outlet is in a stagnant state for a long time. Consequently, a dead zone is formed in the area near the partition between the inlet and outlet.

Because the coolant in the area between the partition and the output port keeps high temperature for a long time, and even the coolant in the area between the input port and the partition heats up due to heat exchange, causing the coolant in the dead water area to maintain high temperature for a long time, resulting in local overheating of the motor , the power loss increases, and the working efficiency of the motor decreases.

Accordingly, the inventor proposes a new motor cooling scheme to reduce the problem of local overheating of the motor. In order to make the above objects, features and advantages of the present invention more comprehensible, specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

Referring to Fig. 1, Fig. 1 shows a motor 1 used in an electric vehicle, the motor 1 can be connected to a transmission input shaft to provide driving force. The motor 1 includes a housing 2 and a cooling channel 3 located in the housing 2. The cooling channel 3 surrounds the central axis of the housing 2. The coolant can circulate in the cooling channel 3 to absorb the heat generated by the motor. A partition 4 is provided inside the cooling channel 3 , and the partition 4 surrounds the central axis of the housing 2 to partition the cooling channel 3 into two sub-channels in the axial direction, namely a first sub-channel 31 and a second sub-channel 32 . Referring to FIG. 2 , the partition member 4 has a connecting channel 30 communicating with the first sub-channel 31 and the second sub-channel 32 . The two sub-channels have an input port 310 and an output port 320 respectively. For example, the first sub-channel 31 has an input port 310, and the second sub-channel 32 has an output port 320. Both the input port 310 and the output port 320 are circumferentially spaced from the connecting channel 30. set up.

The flow direction of the coolant is: flow into the first sub-channel 31 from the input port 310, then divide into two paths, and flow toward the connecting channel 30 along _two opposite directions A1 and A2 around the circumference of the housing ₂ ;

After converging to the connecting channel 30, flow into the second sub-channel 32 along _two opposite directions A1 and A2 respectively _;

Then flow to the output port 320 along two opposite directions A ₁ and A ₂ , and output after converging at the output port 320 . The coolant absorbs the heat generated by the motor during the flow process to achieve the purpose of cooling the motor.

Both the input port 310 and the output port 320 are separated from the connecting channel 30 in the circumferential direction, so that the input port 310 and the connecting channel 30 have no overlapping area along the axial direction of the housing 2, and the output port 320 and the connecting channel 30 have no overlapping area along the axial direction of the housing 2. overlapping area. This ensures that the coolant input from the input port 310 can flow in two opposite circumferential directions A ₁ and A ₂ in the first sub-channel 31 , and finally converge to the connecting channel 30 . Correspondingly, the coolant input from the connection channel 30 into the second sub _- channel 32 can be converged to the output port 320 along _two opposite circumferential directions A1 and A2 for output.

If the input port 310 and the connecting channel 30 have an overlapping area in the axial direction, a large amount of coolant input from the input port 310 will flow to the connecting channel 30, and only a small amount of cooling fluid will flow to both sides of the input port 310 in the circumferential direction, resulting in the first The coolant in the sub-channel 31 is in a stagnant state for a long time to form a dead water zone. Similarly, if the output port 320 and the connecting channel 30 have an overlapping area in the axial direction, a dead water area will be formed in the second sub-channel 32 .

With the motor cooling scheme of the present technical solution, the coolant in the first sub-channel 31 , the second sub-channel 32 and the connecting channel 30 is in a state of continuous flow, and no dead water zone will be formed. Therefore, the coolant in the entire cooling passage 3 is in a state of continuous flow, which reduces the probability of forming a dead water zone. This can eliminate the problem of local overheating of the motor 1 , reduce power loss, and improve the working efficiency of the motor 1 .

Referring to FIG. 1 , the casing 2 includes a water jacket 20 and a motor casing 21 outside the water jacket 20 , and a cooling channel is formed between the water jacket 20 and the motor casing 21 . An annular groove 22 is formed on the outer surface of the water jacket 20 , and the motor casing 21 seals the annular groove 22 to form the cooling channel 3 .

Referring to Fig. 2, Fig. 2 is a perspective view of the water jacket 20 in the housing 2, the input port 310 and the output port 320 are located on the same straight line parallel to the central axis of the housing 2, and are separated from the connecting channel 30 by 180° in the circumferential direction. Both the input port 310 and the output port 320 correspond to the connecting channel 30 along the radial direction of the housing 2 . In this way, in the first sub-channel 31, the flow lengths of the coolant input from the input port 310 to the connecting channel ₃₀ in _two opposite directions A1 and A2 are basically the same, and the cooling effect of the two parts of the coolant can be effectively utilized. This improves the cooling efficiency of the coolant as a whole. When the distance between the input port 310 and the connecting channel 30 is not 180° in the circumferential direction, the coolant flows from the input port 310 to the connecting channel 30 along a short circumferential path, and the flow length of this part of the coolant is short and the effective cooling time is short , and its cooling function utilization rate is low.

On the other hand, in the first sub-channel 31, there is little difference in the amount of coolant flowing from the input port 310 to the connecting channel ₃₀ in _two opposite directions A1 and A2. ) are close in cooling effect, and each part of the motor 1 is cooled evenly.

Correspondingly, in the second sub-channel 32, the flow length and dosage of the coolant flowing in from the connecting channel ₃₀ to the output port 320 along the _two opposite directions A1 and A2 are _{approximately} the same, and along the two opposite directions A1 and A2 ₂ The cooling effect of the flowing coolant on the motor 1 is close. Therefore, various parts of the motor 1 can be cooled more evenly.

Referring to FIGS. 2-4 , the axial width H ₁ of the first sub-channel 31 where the input port 310 is located gradually decreases along the circumferential direction—from the input port 31 to the connecting channel 30 (not shown in FIG. 3 ). Heat flux It has the following proportional relationship with the heat transfer coefficient (h) and the temperature difference (ΔT) between the coolant and the shell 2: While h∝v (v is the coolant flow rate), the heat flux can be used to characterize the ability of the coolant to absorb heat from the shell 2 .

As the axial width H ₁ of the first sub-channel 31 gradually decreases from the input port 310 to the connecting channel 30 along the circumferential direction, the coolant flow rate v gradually increases, and the heat transfer coefficient h gradually increases. As the coolant absorbs heat from the housing 2 during the flow, the temperature difference ΔT gradually decreases. But since h also gradually increases, this can compensate for the temperature difference ΔT to decrease the heat flux effect, maintaining the heat flux It is basically constant, which makes the ability of the coolant flowing in the first sub-channel 31 along the circumferential direction to absorb heat from the shell 2 relatively consistent during the flow process, and the heat absorption continuity is good, and the cooling effect of the coolant is more effectively utilized.

The axial width H1 of the _first sub-channel ₃₁ gradually decreases along _two opposite directions A1 and A2 in the circumferential direction from the input port 310 to the connecting channel ₃₀ , and from the input port 310 along _two opposite directions A1 and A2 The coolant flowing to the connecting channel 30 has a constant heat flux When the input port 310 is separated from the connecting channel 30 by 180° in the circumferential direction, in the first sub-channel 31, the coolant heat flux flowing from the input port 310 to the connecting channel 30 is divided into two paths It is relatively close, and the cooling effect on the motor 1 (refer to FIG. 1 ) is more balanced.

The axial width _H2 of the second sub-channel 32 where the output port 320 is located decreases gradually from the connecting channel 30 (not shown in FIG. 4 ) to the output port 320 in the circumferential direction. heat flux The proportional relationship with the heat transfer coefficient (h), the temperature difference (ΔT) between the coolant and the housing 2, and the proportional relationship between the heat transfer coefficient (h) and the coolant flow rate, the cooling flow from the connecting channel 30 to the output port 320 The heat flux of the coolant is approximately constant, and the coolant flowing in the circumferential direction in the second sub-channel 32 has a consistent heat absorption capacity during the continuous flow process, and the heat absorption continuity is good.

The axial width _H2 of the second sub-channel 32 is set to gradually decrease from the connecting channel 30 to the output port ₂₀ in _two opposite directions A1 and A2 in the circumferential direction, and flows from the connecting channel 30 to the output port 320 in two ways. The coolant has a constant heat flux When the output port 320 is separated from the connecting channel 30 by 180° in the circumferential direction, the coolant heat flux of the second sub-channel 32 flowing from the connecting channel 30 to the output port 320 in _two opposite directions A1 and A2 is relatively consistent, and the motor ₁ The cooling effect is more balanced.

It can be set that the axial width H ₁ of the first sub-channel 31 gradually decreases from the input port 310 to the connecting channel 30 in two opposite circumferential directions A ₁ and A ₂ , and the axial width H ₂ of the second sub-channel 32 Along these _two opposite directions A1 and A2 gradually decrease from the connecting channel ₃₀ to the output port 320, which can realize the coolant heat flux in the whole cooling channel 3 It tends to be consistent, and the heat absorption is continuous.

The axial width H of the cooling passage 3 may be constant along the circumferential direction, and the axial width of the partition 4 may be constant along the circumferential direction. In this way, while the axial width H1 of the first sub-channel 31 decreases gradually from the input port 310 to the connecting channel 30 in the circumferential direction, the axial width _{H2 of} the second sub-channel 32 extends from the connecting channel 30 to the output port in the circumferential direction. Port 320 tapers down. At this time, there is a non-zero included angle between the central axis of the partition 4 and the central axis of the cooling channel 3 , and the partition 4 is an ellipse.

As a modified example, the partition can include a body coaxially arranged with the cooling channel and a protrusion protruding into the first sub-channel, or a side edge of the cooling channel on one side of the first sub-channel has a protrusion protruding into the first sub-channel. For the protrusion, the axial width of the protrusion along the axial direction of the body can be set to gradually increase along the circumferential direction from the input port to the connecting channel, so as to realize that the axial width of the first sub-channel gradually decreases along the circumferential direction from the input port to the connecting channel.

As another modified example, the partition can include a body coaxially arranged with the cooling channel and a protrusion protruding into the second sub-channel, or a side edge of the cooling channel on one side of the second sub-channel has a protrusion protruding into the second sub-channel. For the protruding protrusion, the axial width of the protrusion along the axial direction of the body can be gradually increased along the circumferential direction from the connecting channel to the output port, so as to realize that the axial width of the second sub-channel gradually decreases along the circumferential direction from the input port to the connecting channel .

Compared with the above modification scheme, the forming process of the cooling channel 3 in this embodiment is relatively simple, and the feasibility is higher.

Referring to FIG. 3 , when the axial width H of the cooling channel 3 is constant, the axial width H ₁ of the first sub-channel 31 where the input port 310 is located at the position of the input port 310 is greater than half of the axial width H of the cooling channel 3 . The axial width H1 of the _first sub-channel 31 has a relatively obvious decrease trend from the input port 310 to the connecting channel 30 along the circumferential direction, and the slope of the change is relatively large, which can provide a large adjustment space to compensate for the temperature difference as much as possible. ΔT decreases for heat flux effect, maintaining the heat flux constant.

Further, referring to Fig. ₄ , the axial width H3 and H4 of each sub-channel at the position of the connecting channel 30 can be equal to half of the axial width H of the cooling channel ₃₀ , and the axial width of each sub-channel near the connecting channel 30 H ₃ and H ₄ are approximately equal to half the axial width H of the cooling channel 3 . At this time, when the coolant flows from the first sub-channel 31 to the second sub-channel 32 through the connecting channel 30, the coolant flowing in the first sub-channel 31 along the _first direction A1 flows into the connecting channel 30 and then along the second direction. A ₂ flows into the second sub-channel 32 , the coolant flowing in the first sub-channel 31 along the second direction A ₂ flows into the connecting channel 30 and then flows into the second sub-channel 32 along the first direction A ₁ , in the connecting channel 30 along the circumferential direction The flow rate and flow rate of the coolant flowing from the first sub-channel 31 into the second sub-channel 32 are basically the same on both sides, so as to avoid the poor local cooling effect of the motor 1 (refer to FIG. 1 ) caused by a small coolant flow rate on one side. The problem.

Referring to Fig. 2-Fig. 4, when the input port 310 and the output port 320 are separated from the connecting channel 30 by 180° in the circumferential direction, the first sub-channel 31 and the second sub-channel 32 are set to be all about the input port 310, the output port 320 and the The plane where the connecting channel 30 is located is symmetrical. The axial width H ₁ of the first sub-channel 31 decreases from the input port 310 to the connecting channel 30 (not shown in FIG. 3 ) along the two opposite directions A ₁ and A ₂ in the circumferential direction with the same slope, so that the first sub-channel In 31, the coolant flow rate, flow velocity v and heat flux flowing from the input port 310 to the connecting channel ₃₀ along _two opposite directions A1 and A2 are the same.

Correspondingly, the axial width H ₂ of the second sub-channel 32 sub-channel 32 decreases from the connecting channel 30 to the output port 320 in two opposite circumferential directions A ₁ and A ₂ with the same slope, so that the second sub-channel 32 The coolant flow rate, flow velocity v and heat flux flowing from the connecting channel ₃₀ to the output port 320 in _two opposite directions A1 and A2 are the same. In this way, the axial width H1 of the first sub-channel 31 where the input port 310 is located at the position of the input port 310 is greater than half of the axial width H _of the cooling channel ₃ , and the axial width H3 of each sub-channel at the position of the connecting channel 30 and _H4 can be equal to half of the axial width H of the cooling channel 30, so that the heat flux of the coolant flowing in the entire cooling channel 3 in each area All can have a high degree of consistency, which can better solve the problem of poor local cooling effect of the motor.

As a modified example, the axial width of the first sub-channel and the axial width of the second sub-channel may be constant along the circumferential direction. In both cases of constant and non-constant, the axial width of the first sub-channel where the input port is located can be set to be greater than the axial width of the second sub-channel where the output port is located. In this way, the effective cooling area of the low-temperature coolant entering the first sub-channel from the input port is relatively large, and the flow velocity v of the high-temperature coolant flowing into the second sub-channel from the connecting channel is fast, and the heat flux The loss is compensated, and the cooling effect of the coolant in the second sub-channel is maintained to a certain extent.

Referring to FIG. 2 and FIG. 4 , in the present technical solution, the connecting channel 30 is a gap formed in the partition member 4 . As an improvement, the connecting passage can be an axial through hole or an axial through groove.

Although the present invention is disclosed above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, so the protection scope of the present invention should be based on the scope defined in the claims.

Claims (10)

1. A motor, comprising a housing and a cooling channel located in the housing, the cooling channel surrounds the central axis of the housing, and a partition is provided in the cooling channel; It is characterized in that the partition part divides the cooling channel into two sub-channels in the axial direction, the partition part has a connecting channel connecting the two sub-channels, and the two sub-channels respectively have an input port and an output port The input port and the output port are spaced apart from the connecting channel along the circumferential direction. 2. The motor according to claim 1, wherein the axial width of the sub-channel where the input port is located is greater than the axial width of the sub-channel where the output port is located. 3. The motor according to claim 1, wherein the axial width of the sub-channel where the input port is located gradually decreases along the circumferential direction from the input port to the connecting channel, and/or the The axial width of the sub-channel where the output port is located gradually decreases along the circumferential direction from the connecting channel to the output port. 4. The electric machine according to claim 3, wherein the axial width of the cooling channel is constant along the circumferential direction, and the axial width of the partition member is constant along the circumferential direction. 5 . The motor according to claim 4 , wherein the axial width of the sub-channel where the input port is located at the position of the input port is greater than half of the axial width of the cooling channel. 6. The motor according to claim 5, wherein the axial width of each of the sub-channels at the position of the connecting channel is equal to half of the axial width of the cooling channel. 7. The motor according to any one of claims 1-6, characterized in that, both the input port and the output port are separated from the connecting channel by 180° in the circumferential direction. 8. The motor according to claim 7, wherein each of the sub-channels is symmetrical with respect to a plane in which the input port, the output port and the connecting channel are located. 9. The motor according to claim 1, wherein the connecting channel is a notch. 10. An electric vehicle, characterized by comprising the motor according to any one of claims 1-9.