CN114825713A

CN114825713A - Cooling oil circuit system for electric drive system and vehicle with cooling oil circuit system

Info

Publication number: CN114825713A
Application number: CN202210474375.6A
Authority: CN
Inventors: 沈勇; 李纪强; 毕路; 徐士龙; 巩文涛; 钟如意; 李贝贝; 龚丽红
Original assignee: Weilai Power Technology Hefei Co Ltd
Current assignee: Weilai Power Technology Hefei Co Ltd
Priority date: 2022-04-29
Filing date: 2022-04-29
Publication date: 2022-07-29

Abstract

The invention relates to a cooling oil circuit system for an electric drive system and a vehicle with the cooling oil circuit system. The cooling oil path system for the electric drive system comprises a rotor oil path branch for supplying cooling oil to a rotor of the electric drive system, and a control valve capable of controlling the on-off of the rotor oil path branch is arranged on the rotor oil path branch. The cooling oil path system for the electric drive system can effectively control the cooling oil entering the electric drive rotor through the rotor oil path branch only supplying the cooling oil to the rotor and the control valve controlling the rotor oil path branch, so that the cooling oil can be provided to the rotor under the condition that the rotor needs the cooling oil, for example, the cooling liquid is introduced at high speed, and the cooling liquid is not introduced at low speed, thereby achieving the purposes of improving the energy utilization rate, improving NVH and improving the electric drive efficiency.

Description

Cooling oil circuit system for electric drive system and vehicle with cooling oil circuit system

Technical Field

The invention relates to the technical field of vehicles, in particular to a cooling oil circuit system for an electric drive system and a vehicle with the cooling oil circuit system.

Background

Electric energy is being gradually applied to the automobile industry as clean energy. In the face of this trend, electric drive systems are gradually replacing engines that are primarily fueled by traditional fossil fuels. The development of new energy automobiles is always limited by battery endurance mileage, charging time, battery life and the like. Before the restriction factors such as the battery endurance mileage and the charging time do not have great technical breakthroughs, how to improve the efficiency of the electric drive and the energy utilization rate is the main development direction of the current electric drive design. With the development of new energy automobile industry and consumer demand, electric drive will develop towards high efficiency, high power density and high integration. The mode of increasing voltage can be adopted to improve the power density of the electric drive, the high-voltage platform means higher heating power, and the high heating power brings higher temperature rise to the inside of the electric drive. The high voltage platform presents new challenges to the cooling mode, cooling efficiency, and cooling design of the electric drive, which will be continuously updated as the electric drive develops, and the cooling design will become an important technology for the electric drive structural design.

The main cooling modes of electric drive are water cooling and oil cooling. The main disadvantages of the water cooling method are that the heat resistance exists, the contact between the casing and the stator core is insufficient, and therefore, the cooling efficiency of the water cooling is low. The oil cooling mode adopts contact cooling, and has great advantages in the aspects of heat conduction efficiency and the like. The oil cooling mode is mainly to carry out contact cooling on the stator, the stator coil, the rotor and the like through lubricating oil, the direct contact type cooling mode can reduce the quantity of thermal resistance and heat transfer, and the direct or indirect contact type cooling mode is in contact with a heating source, so that the cooling efficiency is higher, and the cooling effect is better.

In order to meet the requirement of high vehicle speed, the rotating speed of the motor needs to be particularly high, and at the moment, the rotor generates heat seriously and needs to be cooled. Because the rotor is a rotating part and the speed of the rotor is not constant and changes irregularly, the problems of dynamic balance and loss increase are caused after cooling oil is introduced. In case of the above contradiction, the existing cooling oil circuit system for the electric drive system cannot control the oil feeding of the rotor so that the cooling oil is provided to the rotor only in the case of needing the cooling oil.

Therefore, there is a need in the art for a new solution to the above problems.

Disclosure of Invention

In order to solve the above problems in the prior art, that is, to solve the technical problem in the prior art that the cooling oil path system for the electric drive system cannot control the oil inlet of the rotor so that the cooling oil is provided to the rotor only when the cooling oil is needed, the present invention provides a cooling oil path system for the electric drive system. The cooling oil circuit system comprises a rotor oil circuit branch circuit for supplying cooling oil to a rotor of the electric drive system, and a control valve capable of controlling the on-off of the rotor oil circuit branch circuit is arranged on the rotor oil circuit branch circuit. In the cooling oil path system for the electric drive system, the cooling oil entering the rotor of the electric drive system can be effectively controlled by the rotor oil path branch only supplying the cooling oil to the rotor and the control valve positioned on the rotor oil path branch, so that the cooling oil can be provided for the rotor under the condition that the rotor needs the cooling oil, for example, the cooling oil is supplied at a high speed, and the cooling oil is not supplied at a low speed, thereby achieving the purposes of improving the energy utilization rate, improving the NVH (Noise, Vibration and Harshness), and improving the efficiency of the electric drive system.

In a preferred embodiment of the above cooling oil system, the control valve is a mechanical valve or an electromagnetic valve. The mechanical valve has the advantages of simple structure, small size, no need of an electronic controller, no need of programming, easy adjustment and connection and the like; the electromagnetic valve has the advantages of sensitive response, small power, reliable work, low price and the like. Through the above arrangement, the mechanical valve or the electromagnetic valve can effectively control the cooling oil entering the rotor of the electric driving system, thereby being beneficial to reducing energy loss and improving the efficiency of the electric driving system.

In a preferred embodiment of the above cooling oil passage system, the control valve is the mechanical valve, and includes: the mechanical valve body is provided with a valve inlet, a valve outlet and a guide groove positioned in the mechanical valve body, the guide groove is provided with a first side wall and a second side wall which extend along the length direction of the mechanical valve body and are opposite to each other, and the valve inlet and the valve outlet are respectively arranged at two opposite ends of the guide groove and are communicated with the guide groove; the first valve core is positioned in the guide groove, and a first elastic piece which is respectively abutted against the first valve core and the first side wall is arranged between the first valve core and the first side wall; and a second valve core which is positioned in the guide groove and arranged in parallel with the first valve core, and a second elastic part which is respectively abutted against the second valve core and the second side wall is arranged between the second valve core and the second side wall, wherein the first elastic part and the second elastic part force the first valve core and the second valve core to be mutually and hermetically abutted through elastic force, and when the rotating speed of the rotor reaches a preset value, the first valve core and the second valve core are separated from each other under the action of centrifugal force against the elastic force. Through foretell setting, when the electricity driven system is static or low rotational speed, first elastic component and second elastic component exert on first case and second case elasticity be greater than by the rotatory centrifugal force that causes of rotor and reverse with this elasticity, consequently under the extrusion of elasticity, first case and second case mutually form sealed supporting to fluid intercommunication between trip valve import and the valve export realizes blocking of oil circuit, and then prevent that the coolant oil from flowing into the rotor. When the rotor is in high rotation speed, the centrifugal force is larger than the elastic force exerted by the first elastic piece and the second elastic piece, the first valve core and the second valve core are separated from each other under the action of the centrifugal force, the valve inlet and the valve outlet are communicated through fluid, and therefore cooling oil can flow to the rotor through the mechanical valve to cool the rotor. The cooling oil entering the electric drive rotor can be effectively controlled through a simple mechanical structure, so that the purpose that the rotor is communicated with the oil at a high speed and is not communicated with the oil at a low speed can be achieved.

In a preferred embodiment of the above cooling oil system, the mechanical valve body is configured to be formed by a part of a rotor shaft of a rotor of the electric drive system. Through the arrangement, a part of the rotor shaft is constructed into the mechanical valve body, and the mechanical valve body does not need to be additionally manufactured, so that the mechanical valve is directly integrated in the rotor shaft, the manufacturing cost of the mechanical valve can be reduced, and the rotor oil path branch is shortened by enabling a part of the rotor shaft to form a part of the rotor oil path branch, so that the space occupied by the cooling oil path system is reduced.

In a preferred embodiment of the cooling circuit system, the first elastic member is fixedly connected to the first valve core and the first side wall, and the second elastic member is fixedly connected to the second valve core and the second side wall. With the above arrangement, the first and second elastic members can form stable connections with the first and second spools and the guide groove, respectively, and seal the two spools against each other by applying elastic force to block the cooling oil from entering the rotor.

In a preferred embodiment of the above cooling oil path system, the first elastic member and the first valve element respectively form an abutment with the first side wall in a non-fixed connection, and the second elastic member and the second valve element respectively form an abutment with the second side wall in a non-fixed connection. "non-fixed connection" means that the first elastic member is sandwiched between the first valve element and the second side wall, but neither end thereof is fixed to the first valve element and the second side wall; the second elastic member is sandwiched between the second valve core and the second sidewall, but both ends thereof are not fixed to the second valve core and the second sidewall, so that the manufacturing process of the mechanical valve is simplified.

In a preferred embodiment of the above cooling oil passage system, the control valve is the solenoid valve, and includes: the electromagnetic valve body is internally provided with an oil inlet, an oil outlet and a control cavity, a sealing seat is fixed in the control cavity, and the sealing seat is provided with through holes which are respectively communicated with the oil inlet positioned at the upstream and the oil outlet positioned at the downstream; and the sealing assembly comprises a sealing block matched with the through hole in shape and an electromagnetic actuating assembly, the sealing block is movably fixed in the control cavity through a sealing elastic piece, the sealing elastic piece is configured to enable the sealing block to seal the through hole through elastic force, and the electromagnetic actuating assembly is configured to apply actuating force overcoming the elastic force to the sealing block so as to move the sealing block away from the through hole. Through the arrangement, the electromagnetic valve can lead the sealing block to block the through hole on the sealing seat so as to prevent the cooling oil from flowing to the rotor. When oil needs to be filled into the rotor, the electromagnetic valve can drive the electromagnetic actuating device through electric control, so that the electromagnetic actuating device applies force to the sealing block, the sealing block is moved away from the through hole, and the electromagnetic valve is conducted. The setting can be according to the on/off of demand control solenoid valve, and then whether the logical oil of control rotor, more high-efficient intelligence.

In a preferred embodiment of the above cooling oil path system, the seal block includes a first seal portion and a second seal portion connected to each other, the first seal portion is of a cylindrical structure and has a first end and a second end opposite to each other, and the second seal portion is of a tapered table structure with a cross section gradually increasing in an outward direction from the second end and is located downstream of the first seal portion. Through foretell setting, the through-hole that has the looks isostructure can be plugged up to sealed piece, forms line contact seal and combines together with face contact seal, has effectively improved the sealed effect of sealed piece.

In a preferred embodiment of the above cooling oil system, the actuating assembly includes: the movable iron core, the static iron core surrounding the movable iron core, the coil surrounding the static iron core and the ejector pin fixedly connected with the movable iron core are arranged in the shell, wherein the ejector pin is configured to extend into the control cavity and translate towards the sealing block under the action of magnetic force when the coil is electrified and abut against the first end so that the sealing block is moved away from the through hole. Through the arrangement, the electromagnetic valve can be switched on and off through simple electric control. When the electromagnetic valve is electrified, the coil generates a magnetic field to magnetize the static iron core, and generates repulsive downward force with the movable iron core, so that the movable iron core drives the thimble to move downward and applies downward force to the sealing block to move away from the through hole on the sealing seat, and the conduction of the electromagnetic valve is further realized.

In a preferred technical solution of the above cooling oil system, the movable iron core is connected to the housing through an iron core elastic member, so that the iron core elastic member forces the movable iron core and the ejector pin to move away from the sealing block when the coil is powered off. Through foretell setting, the solenoid valve is behind the outage, and the elastic force that the elastic component applyed to moving the iron core can move the iron core and drive the thimble and remove from the seal block to make the through-hole on the seal receptacle block up to the seal block, and then prevent the coolant oil entering rotor.

In a preferred embodiment of the above cooling oil path system, the sealing block is configured to move away from the through hole when the hydraulic pressure applied to the sealing block from the oil inlet exceeds a predetermined pressure value. Through foretell setting, can make hydraulic pressure force act on the seal block through the flow of control cooling oil, and then realize that the rotor leads to oil. The arrangement enables the electromagnetic valve to still realize the control of the on-off of the rotor oil way when the circuit fails, and is beneficial to ensuring the stability and reliability of the work of the electromagnetic valve.

In a preferred embodiment of the above cooling oil path system, the cooling oil path system further includes a stator oil path branch for providing cooling oil to a stator of the electric drive system and a bearing oil path branch for providing cooling oil to a bearing of the electric drive system, and the stator oil path branch and the bearing oil path branch are both connected in parallel with the rotor oil path branch. Through foretell setting, cooling oil piping system can supply the cooling oil to stator, rotor and bearing respectively through independent cooling oil branch road each other to ensure the normal work of electricity system, and improve the work efficiency of electricity system, reduce energy loss.

In order to solve the above problems in the prior art, that is, to solve the technical problem in the prior art that a cooling oil path system for electric drive cannot control the oil inlet of a rotor so that the rotor is provided with cooling oil only when the cooling oil is needed, the invention further provides a vehicle. The vehicle includes the cooling oil circuit system of any one of the preceding claims. The cooling oil path system for the electric drive system in the vehicle can effectively control the cooling oil entering the rotor of the electric drive system, so that the cooling oil can be introduced at a high speed, and is not introduced at a low speed, thereby achieving the purposes of improving the energy utilization rate, improving the NVH and improving the efficiency of the electric drive system.

The cooling oil path system for the electric drive system is characterized by comprising a rotor oil path branch for supplying cooling oil to a rotor of the electric drive system, and a control valve for controlling the on-off of the rotor oil path branch is arranged on the rotor oil path branch.

Scheme 2. the cooling oil circuit system for electric drive system according to scheme 1, characterized in that, the control valve is mechanical valve or solenoid valve.

Scheme 3. the cooling oil circuit system for electric drive system according to scheme 2, characterized in that, the control valve is the mechanical valve and includes:

the mechanical valve body is provided with a valve inlet, a valve outlet and a guide groove positioned in the mechanical valve body, the guide groove is provided with a first side wall and a second side wall which extend along the length direction of the mechanical valve body and are opposite to each other, and the valve inlet and the valve outlet are respectively arranged at two opposite ends of the guide groove and are communicated with the guide groove;

the first valve core is positioned in the guide groove, and a first elastic piece which is respectively abutted against the first valve core and the first side wall is arranged between the first valve core and the first side wall; and

a second valve core which is positioned in the guide groove and is arranged in parallel with the first valve core, and a second elastic piece which is respectively abutted against the second valve core and the second side wall is arranged between the second valve core and the second side wall,

wherein the first and second elastic members force the first and second valve spools to be sealed against each other by an elastic force, and when the rotational speed of the rotor reaches a predetermined value, the first and second valve spools are separated from each other against the elastic force by a centrifugal force.

Scheme 4. the cooling oil circuit system for the electric drive system according to scheme 3, characterized in that the mechanical valve body is configured to be formed by a part of a rotor shaft of a rotor of the electric drive system.

The cooling oil system for the electric drive system of the claim 3, characterized in that the first elastic member is fixedly connected with the first valve core and the first side wall respectively, and the second elastic member is fixedly connected with the second valve core and the second side wall respectively.

The cooling oil circuit system for the electric drive system according to the claim 3 is characterized in that the first elastic member is respectively abutted against the first valve core and the first side wall in an unfixed connection mode, and the second elastic member is respectively abutted against the second valve core and the second side wall in an unfixed connection mode.

Scheme 7. the cooling oil circuit system for electric drive system according to scheme 2, characterized in that, the control valve is the solenoid valve and includes:

the electromagnetic valve body is internally provided with an oil inlet, an oil outlet and a control cavity, a sealing seat is fixed in the control cavity, and the sealing seat is provided with through holes which are respectively communicated with the oil inlet positioned at the upstream and the oil outlet positioned at the downstream; and

a sealing assembly including a sealing block shaped to match the through hole and an electromagnetic actuating assembly, the sealing block movably secured within the control cavity by a sealing spring and the sealing spring configured to cause the sealing block to seal the through hole by a spring force, the electromagnetic actuating assembly configured to apply an actuating force to the sealing block to overcome the spring force to move the sealing block away from the through hole.

The cooling oil circuit system for the electric drive system according to claim 7, characterized in that the seal block includes a first seal portion and a second seal portion connected to each other, the first seal portion is of a cylindrical structure and has opposite first and second ends, and the second seal portion is of a tapered table structure having a cross section that gradually increases in an outward direction from the second end and is located downstream of the first seal portion.

Scheme 9. the cooling oil circuit system for electric drive system according to scheme 8, characterized in that, the actuating assembly includes:

a shell, a movable iron core, a static iron core surrounding the movable iron core, a coil surrounding the static iron core, and a thimble fixedly connected with the movable iron core are arranged in the shell,

wherein the thimble is configured to extend into the control cavity and to magnetically translate toward the seal block and against the first end to move the seal block away from the through-hole when the coil is energized.

The cooling oil system for the electric drive system of claim 9, wherein the plunger is connected to the housing by a plunger spring such that the plunger spring urges the plunger and the needle to move away from the seal block when the coil is de-energized.

The cooling oil system for an electric drive system of claim 7, wherein the seal block is configured to move away from the through bore when the hydraulic force applied to the seal block from the oil inlet exceeds a predetermined pressure value.

Scheme 12. a cooling oil circuit system for an electric drive system according to any of the claims 1-11, characterized in that the cooling oil circuit system further comprises a stator oil circuit branch for providing cooling oil to a stator of the electric drive system and a bearing oil circuit branch for providing cooling oil to a bearing of the electric drive system, and that the stator oil circuit branch and the bearing oil circuit branch are both formed in parallel with the rotor oil circuit branch.

An arrangement 13, characterized in that the vehicle comprises a cooling oil circuit system according to any one of the arrangements 1-12.

Drawings

Preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which:

FIG. 1 is a schematic structural diagram of an embodiment of a cooling oil system of the present invention;

FIG. 2 is a schematic structural diagram of an embodiment of a mechanical valve in the cooling oil circuit system of the present invention;

fig. 3 is a schematic structural diagram of an embodiment of the electromagnetic valve in the cooling oil circuit system of the invention.

List of reference numerals:

1. cooling the oil circuit system; 10. a rotor oil path branch; 11. a rotor; 12. a control valve; 13. a mechanical valve; 131. a mechanical valve body; 132. a valve inlet; 133. a valve outlet; 134. a guide groove; 341. a first side wall; 342. a second side wall; 135. a first valve spool; 136. a second valve core; 137. a first elastic member; 138. a second elastic member; 14. an electromagnetic valve; 141. an electromagnetic valve body; 142. an oil inlet; 143. an oil outlet; 144. a control chamber; 145. a sealing seat; 146. a through hole; 147. a sealing block; 148. a sealing elastic member; 149. a spring seat; 150. an electromagnetic actuating assembly; 501. a housing; 502. a movable iron core; 503. a stationary iron core; 504. a coil; 505. a thimble; 506. an end cap; 507. an iron core elastic member; 20. a stator oil way branch; 21. a stator; 30. a bearing oil way branch; 31. a bearing; 40. a lubricating oil sump; 50. a suction filtration device; 60. an electronic oil pump; 70. a filter pressing device; 80. a heat exchanger.

Detailed Description

Preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only for explaining the technical principle of the present invention, and are not intended to limit the scope of the present invention.

It should be noted that in the description of the present invention, the terms of direction or positional relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, which are only for convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Furthermore, it should be noted that, in the description of the present invention, unless otherwise explicitly specified or limited, the terms "disposed" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; either directly or indirectly through intervening media, or through the communication between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In order to solve the technical problem that the cooling oil path system for the electric drive system in the prior art cannot control the oil inlet of the rotor so that the cooling oil is provided for the rotor under the condition that the cooling oil is needed, the invention provides a cooling oil path system 1 for the electric drive system. The cooling oil path system 1 comprises a rotor oil path branch 10 for supplying cooling oil to a rotor 11 of the electric drive system, and a control valve 12 capable of controlling the on-off of the rotor oil path branch 10 is arranged on the rotor oil path branch 10.

In one or more embodiments, the vehicle (not shown) of the present invention is a pure electric vehicle. Alternatively, the vehicle may be a hybrid vehicle, or other suitable vehicle. The vehicle has an electric drive system for powering the vehicle, wherein the electric drive system includes, but is not limited to, a rotor having a rotor shaft, a stator, a bearing, and the like. In order to ensure that the electric drive system can stably and efficiently output power, the vehicle also has a cooling oil path system 1 for the electric drive system.

Fig. 1 is a schematic structural diagram of an embodiment of the cooling oil circuit system of the present invention. As shown in fig. 1, in one or more embodiments, the cooling oil path system 1 includes a lubricant oil pool 40, a suction filter device 50, an electronic oil pump 60, a filter press device 70, and a heat exchanger 80. The lubricant sump 40 is capable of storing a certain amount of lubricant. The lubricant from the lubricant sump 40 flows first into the suction filter 50 and then into the oil pump 60. This suction filter device 50 can filter the large granule impurity in the lubricating oil to avoid impurity to cause the harm to electronic oil pump 60. The electronic oil pump 60 can provide circulating power of the lubricating oil to ensure that the lubricating oil can flow out from the lubricating oil pool 40. The lubricating oil from the electronic oil pump 60 flows through the filter press device 70 before flowing through the heat exchanger 80. The filter pressing device 70 can further filter the lubricating oil from the electronic oil pump 60 to filter out smaller particles of impurities in the lubricating oil, so as to avoid the impurities from damaging parts needing to be lubricated. The lubricating oil from the heat exchanger 80 flows to the oil passages and finally returns to the lubricating oil pool 40. The heat exchanger 80 is capable of cooling the hot lubricating oil to ensure that the lubricating oil flowing to each branch can cool the stator 21, the rotor 11, and the bearing 31, and at this time, the lubricating oil also functions as cooling oil, and is also referred to as cooling oil.

As shown in fig. 1, the cooling oil path system 1 of the present invention includes three oil path branches connected in parallel, which are a rotor oil path branch 10, a stator oil path branch 20, and a bearing oil path branch 30. The upstream ends of the rotor oil path branch 10, the stator oil path branch 20, and the bearing oil path branch 30 are connected to the heat exchanger 80. When it is necessary to feed oil to the rotor 11, the stator 21, and the bearing 31 to cool them, the cooled lubricating oil from the heat exchanger 80 flows to the rotor oil path branch 10, the stator oil path branch 20, and the bearing oil path branch 30, respectively, to cool the rotor 11, the stator 21, and the bearing 31. Finally, the lubricant oil flowing out of the rotor 11, the stator 21, and the bearing 31 flows back to the lubricant oil pool 40. As shown in fig. 1, a control valve 12 is provided on the rotor oil passage branch 10 to control the oil supply and oil cut of the rotor 11.

Fig. 2 is a schematic structural diagram of an embodiment of a mechanical valve in the cooling oil circuit system of the invention. As shown in fig. 2, in one or more embodiments, in the cooling oil path system 1 of the present invention, the control valve 12 provided on the rotor oil path branch 10 is a mechanical valve 13.

The mechanical valve 13 includes a mechanical valve body 131. In one or more embodiments, the mechanical valve body 131 is part of an upstream rotor shaft (not labeled in the figures) of the rotor 11 and has a valve inlet 132, a valve outlet 133, and a guide slot 134. The mechanical valve 13 is installed in the rotor shaft, and the valve inlet 132 and the valve outlet 133 are respectively communicated with the rotor oil passage, so that the on-off of the rotor oil passage branch 10 can be controlled. The guide groove 134 is formed in the mechanical valve body 131, i.e., in the rotor shaft, and communicates with a cooling oil passage (not labeled) of the rotor 11. The valve inlet 132 is located on the illustrated left side of the guide slot 134 and the valve outlet 133 is located on the illustrated right side of the guide slot 134. In an alternative embodiment, the mechanical valve body 14 of the mechanical valve 13 is independent of the rotor shaft of the rotor 11.

The mechanical valve 13 also includes a first spool 135 and a second spool 136. The first spool 135 and the second spool 136 are provided in the guide groove 134. Between the first spool 135 and the first sidewall 341 of the guide groove 134, a first elastic member 137 is provided. The first elastic member 137 is sandwiched between the first sidewall 341 and the first valve spool 135. A second elastic member 138 is also provided between the second spool 136 and the second side wall 342 of the guide groove 134. The second elastic member 138 may be the same as or different from the first elastic member 137. The second resilient member 138 is sandwiched between the second side wall 342 and the second spool 136. In one or more embodiments, the first elastic member 137 and the second elastic member 138 are springs.

In an alternative embodiment, a plurality of first elastic members 137 may be disposed between the first spool 135 and the first sidewall 341 of the guide groove 134. A plurality of second elastic members 138 may also be disposed between the second spool 136 and the second side wall 342 of the guide groove 134. Alternatively, the first elastic member 137 may be fixedly coupled to the first sidewall 341 and the first valve element 135 by laser welding or other suitable processes. Alternatively, the second resilient member 137 may be fixedly connected to the second side wall 342 and the second valve element 136 by laser welding or other suitable processes.

When the first valve spool 135, the second valve spool 136, the first elastic member 137, and the second elastic member 138 are fitted into the rotor shaft of the rotor 11, the rotor shaft needs to be cut open and the guide groove 134 is machined therein. Then the first valve core 135, the second valve core 136, the first elastic member 137 and the second elastic member 138 are placed in the guide groove 134, and finally the rotor shaft is joined and restored by laser welding.

The first spool 135 and the second spool 136 are balanced by centrifugal force, gravity and elastic force, and the centrifugal force applied to the first spool 135 and the second spool 136 increases as the rotation speed of the rotor 11 increases. When the centrifugal force is greater than the sum of the spring force and the gravitational force, the two spools are able to overcome the spring force of the spring and separate from each other, thereby establishing fluid communication between the valve inlet 132 and the valve outlet 133. When the vehicle of the present invention is in a stationary state or a low speed state, the first spool 135 and the second spool 136 are in a sealing position against each other, i.e., the position shown in fig. 2, by the elastic force of the first elastic member 137 and the second elastic member 138. At this time, the communication between the valve inlet 132 and the valve outlet 133 is blocked by the first spool 135 and the second spool 136, and the cooling oil cannot enter the rotor. When the vehicle speed of the vehicle is higher than a certain value, for example, higher than 100km/h, the rotation speed of the rotor is also high, for example, the corresponding rotation speed of the rotor is 12000r/min, at this time, the first valve core 135 and the second valve core 136 compress the first elastic member 137 and the second elastic member 138 respectively and separate from each other under the action of centrifugal force, so that the oil path is conducted, and the cooling oil enters the rotor 11 and cools it. Further, the higher the rotation speed of the rotor 11, the larger the centrifugal force, and the larger the flow rate into the rotor 11.

Fig. 3 is a schematic structural diagram of an embodiment of the electromagnetic valve in the cooling oil circuit system of the invention. As shown in fig. 3, in one or more embodiments, in the cooling oil path system 1 of the present invention, the control valve 12 disposed on the rotor oil path branch 10 is a solenoid valve 14, and the solenoid valve 14 is located upstream of the rotor 11.

The solenoid valve 14 includes a solenoid valve body 141. An oil inlet 142, an oil outlet 143 and a control chamber 144 are provided in the solenoid valve body 141. An oil outlet 143 is provided at the illustrated lower end of the solenoid valve body 141, and the cooling oil flowing out from the oil outlet 143 can flow to the rotor 11. The oil inlet 142 is a small hole provided in a side wall of the solenoid valve body 141 and penetrating the side wall. In this embodiment, 2 oil inlets 142 are provided on the solenoid valve body 141 at opposite positions. In alternative embodiments, 3 oil inlets 142 may be provided on the solenoid valve body 141, or another suitable number of oil inlets 142 may be provided.

The solenoid valve body 141 also has a seal seat 145 therein. The seal seat 145 is disposed relatively below the oil inlet 142 as shown. The seal seat 145 is integrally formed with the solenoid valve body 141, and the seal seat 145 extends from a circumferential inner wall of the control chamber 144 toward the center of the control chamber 144. A through hole 146 is provided in the seal holder 145. The through hole 146 is formed of an upper portion and a lower portion (based on the orientation shown in fig. 3), and may be considered as being formed of an upstream portion and a downstream portion along the flow direction of the lubricating oil, and the upper portion thereof is cylindrical and the lower portion thereof is frustoconical. In alternative embodiments, the through hole 146 may be cylindrical, rectangular parallelepiped, or other suitable shape.

As shown in FIG. 3, the solenoid valve 14 also includes a seal assembly (not shown). The seal assembly includes a seal block 147 and an electromagnetic actuation assembly 150. A sealing block 147 is movably secured within the control chamber 144 and has a shape that matches the through-hole 146. The sealing block 147 includes a first sealing portion (not labeled) and a second sealing portion (not labeled) connected to each other. The first sealing portion is a cylinder having the same shape as the upper portion of the through hole 146. The second sealing portion is of a truncated cone shape having the same shape as the lower portion of the through hole 146. The second sealing part is connected with the first sealing part through the lower end face of the first sealing part, and the cross section of the second sealing part is gradually increased downwards from the lower end face of the first sealing part. In alternative embodiments, the sealing block 147 may also be cylindrical, spherical, or any other suitable shape, so long as it can cooperate with the sealing seat 145 to block the oil path.

In one or more embodiments, the solenoid valve 14 has a spring seat 149. A spring seat 149 is provided at the downstream end of the solenoid valve body 141, and a seal elastic member 148 is fixed to the spring seat 149. The sealing elastic member 148 is a spring, and the sealing elastic member 148 is connected to the spring seat 149 at one end and to the sealing block 147 at the other end. When the solenoid valve is not energized or no cooling oil flows into the control chamber 144, the sealing block 147 is in a balanced state by its own weight and the elastic force of the sealing elastic member 148, and sealingly blocks the through hole 146 in the sealing seat 145. At this time, the solenoid valve 14 is closed, i.e., the solenoid valve 14 is normally closed.

As shown in fig. 3, electromagnetic actuation assembly 150 includes a housing 501. The housing 501 is fixedly connected to the solenoid valve body 141 by caulking, and a movable core 502, a stationary core 503, a coil 504, an ejector pin 505, and a core elastic member 507 are provided inside the housing 501. Alternatively, the housing 501 and the solenoid valve body 141 may be fixedly connected by other suitable processes. Wherein the plunger 502 is movably fixed in the housing 501. The stationary core 503 surrounds the movable core 502. The coil 504 surrounds the stationary core 503. The thimble 505 is fixed with the plunger 502 by interference fit. An end cover 506 is also fixed to the upper portion of the housing 501. The core elastic member 507 is a spring. The core elastic member 507 is fixed between the end cap 506 and the movable core 502, and is fixedly connected to the end cap 506 and the movable core 502, respectively, by welding or other suitable processes.

The on/off of the solenoid valve 14 can be controlled by both hydraulic pressure and electromagnetic force. When the electromagnetic valve 14 is energized, the coil 504 generates a magnetic field to magnetize the stationary core 503, and the magnetized stationary core 503 and the movable core 502 generate repulsive downward force, so that the movable core 502 drives the plunger 505 to move downward to push open the sealing block 147 and make it completely separate from the through hole 146 on the sealing seat 145, thereby turning on the electromagnetic valve 14. When the solenoid valve 14 is powered off, the plunger 502 moves upward under the elastic force of the plunger elastic member 507 to return to the initial position, and the sealing block 147 moves upward under the elastic force of the sealing elastic member 148 to return to the initial position to block the through hole 146, thereby closing the solenoid valve 14. Therefore, the solenoid valve 14 can be electrically controlled to perform oil supply and oil cut-off whenever necessary.

When the cooling oil enters the control chamber 144 from the oil inlet 142, the cooling oil is accumulated on the seal seat 145 and the seal block 147 and applies a hydraulic force to the seal block 147, and the hydraulic force and the gravity of the seal block 147 resist the elastic force of the seal elastic member 148 together. When the hydraulic pressure is higher than a certain pressure value, for example, when the hydraulic pressure is higher than 1bar, the sealing block 147 overcomes the elastic force of the sealing elastic member 148 to move the sealing elastic member 148 downward by a certain distance and completely disengage from the through hole 146 on the sealing seat 145. At this time, the solenoid valve 14 is turned on, and the cooling oil can flow out from the oil outlet 143 to cool the rotor 11. Therefore, the solenoid valve 14 can ensure that it conducts by increasing hydraulic pressure when the circuit fails. Specifically, the rotor oil supply can be realized by only increasing the rotation speed of the electronic oil pump 60 to increase the total flow of the lubricating oil and increase the system pressure, so that the electromagnetic valve 14 is jacked open under the action of high hydraulic pressure.

So far, the technical solutions of the present invention have been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of the present invention is obviously not limited to these specific embodiments. Equivalent changes or substitutions of related technical features can be made by those skilled in the art without departing from the principle of the invention, and the technical scheme after the changes or substitutions can fall into the protection scope of the invention.

Claims

1. A cooling oil path system for an electric drive system is characterized by comprising a rotor oil path branch for supplying cooling oil to a rotor of the electric drive system, and a control valve for controlling the on-off of the rotor oil path branch is arranged on the rotor oil path branch.

2. The cooling circuit system for an electric drive system as defined in claim 1, wherein the control valve is a mechanical valve or a solenoid valve.

3. The cooling oil system for an electric drive system as defined in claim 2, wherein the control valve is the mechanical valve and comprises:

4. The cooling oil system for an electric drive system of claim 3, wherein the mechanical valve body is configured to be formed by a portion of a rotor shaft of a rotor of the electric drive system.

5. The cooling oil system for the electric drive system as defined in claim 3, wherein the first resilient member is in fixed connection with the first valve spool and the first side wall, respectively, and the second resilient member is in fixed connection with the second valve spool and the second side wall, respectively.

6. The cooling oil system for the electric drive system as defined in claim 3, wherein the first resilient member forms a non-fixed abutment with the first valve spool and the first side wall, respectively, and the second resilient member forms a non-fixed abutment with the second valve spool and the second side wall, respectively.

7. The cooling oil system for an electric drive system as set forth in claim 2, wherein said control valve is said solenoid valve and includes:

8. The cooling oil system for the electric drive system as defined in claim 7, wherein the seal block includes a first seal portion and a second seal portion connected to each other, the first seal portion being of a cylindrical configuration and having opposite first and second ends, the second seal portion being of a tapered mesa configuration with a cross-section that increases progressively in an outward direction from the second end and being located downstream of the first seal portion.

9. The cooling oil system for an electric drive system as defined in claim 8, wherein the actuation assembly comprises:

10. A vehicle, characterized in that the vehicle comprises a cooling oil circuit system according to any one of claims 1-9.