A composite cooling device for an electric machine

Abstract

The motor composite cooling device of the present invention has a housing that is hermetically connected through a front housing cover and a rear housing cover. A reduction gearbox for installing reduction gears is formed by the cooperation of a groove structure between the front housing cover and the inner front motor cover. The "pin" - shaped longitudinal water channels at the top corners of the housing form a circulating water channel through the rear housing cover and the inner water channels of the front motor cover. An oil passage is arranged in the middle of the water channels. The openings at the front and rear ends of the hollow inner cavity of the motor shaft are connected to the oil passage on the housing through the oil channels on the rear housing cover and the front housing cover to form a circulating oil passage. Two cooling systems, namely water cooling and oil cooling, are used to cool the entire motor system simultaneously. The two cooling systems are independent of each other and interact with each other, improving the heat dissipation performance of the motor. The reduction gearbox part adopts an oil cooling system, and the reduction gears are immersed in the cooling oil. When the motor system is running, it can effectively reduce noise, improve the lubrication performance of the reduction gearbox, has a simple structure, good cooling effect, low noise, and high motor driving efficiency.

Description

Technical Field

[0001] The present invention relates to a motor cooling device with a built-in cooling system, belonging to the technical field of motors. Background Art

[0002] In the existing motor technology, the reduction mechanism and the motor body are usually designed as a whole, and the motor and the reduction gear are cooled separately at the same time. For the cooling of the motor, natural cooling or forced cooling by installing a fan is generally adopted, and forced water cooling or oil cooling can also be used; the cooling method of the reduction gear generally adopts installing a cooling fan to cool the gearbox housing, adding cooling coils in the gearbox to cool down by the flow of cooling water, pumping out the lubricating oil through an oil pump for external cooling, or adopting a dual cooling method of a cooling fan + cooling coils. In actual use, generally only a single water cooling or oil cooling method is adopted for the above methods. The water cooling method can only cool the motor, and the oil cooling method can only cool the reduction gearbox, resulting in problems such as unsatisfactory cooling effect, high noise, affecting the lubrication performance of the reduction gearbox, slow heat dissipation, and low working efficiency of the motor. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a compound motor cooling method with both water cooling and oil cooling methods. The cooling device designed by using this method has a simple structure, good cooling effect, low noise, and high motor driving efficiency.

[0004] The motor cooling device of the present invention includes a motor housing. The front and rear ends of the housing are hermetically connected through a front housing cover and a rear housing cover. A motor shaft is arranged at the center of the housing. The front and rear ends of the motor shaft are coaxially installed on the front housing cover and the rear housing cover respectively. A rotor is installed on the motor shaft, and a stator is installed on the inner wall of the housing; a reduction gearbox for installing reduction gears is arranged at the front end of the motor shaft. The feature is that: a motor front cover is further arranged inside the front housing cover, and the front housing cover and the motor front cover cooperate with each other through a rib groove structure to form a gear chamber of the reduction gearbox; A "pin" - shaped water channel is longitudinally arranged along the housing at the top corner of the housing. The top water channel of the "pin" - shaped is the water inlet channel, and the two water channels on both sides of the top are the water return channels; a motor rear cover is arranged inside the rear housing cover. Water inlet holes and water outlet holes are arranged on the rear housing cover and the motor rear cover. Grooved water channels are arranged on the inner walls of the motor rear cover and the motor front cover. The water inlet holes and the water outlet holes are respectively connected to the water inlet channels and the water return channels at the four corners of the housing. The longitudinal water inlet channels and water return channels at the top corners of the housing form a circulating water channel through the grooved water channels inside the motor rear cover and the motor front cover; There is an oil passage at the middle position of the "pin" - shaped water channel at at least one corner of the housing; the motor shaft has a hollow inner cavity with openings at both the front and rear ends of the motor shaft; there is an oil injection hole on the outer wall of the front end cover of the housing, and an oil channel is provided on the inner side. There is a gear chamber oil inlet hole at the lower part of the gear chamber wall of the reduction gearbox; there is also an oil channel on the rear end cover of the housing; the openings at both the front and rear ends of the hollow inner cavity of the motor shaft are respectively connected to the oil channels on the rear end cover and the front end cover of the housing. The hollow inner cavity of the motor shaft, the oil channel on the rear end cover of the housing, and the oil channel of the front end cover of the housing are connected to the oil passage at the corner of the housing to form a circulating oil channel; a oil pump is provided at the connection between the oil channel on the front end cover of the housing and the oil passage at the corner of the housing, and the oil pump can provide circulating power for the cooling oil in the circulating oil channel; There are several oil storage grooves arranged around the gear chamber on the inner wall of the front end cover of the housing; The hollow inner cavity of the motor shaft has steps; The motor housing is rectangular.

[0005] The motor cooling device of the present invention uses two cooling systems, namely water cooling and oil cooling, to cool the entire motor system simultaneously. The water cooling and oil cooling methods coexist. The oil cooling system mainly cools the reduction gearbox part and cools the internal rotor part of the motor through the circulating oil channel; the water cooling system mainly cools the stator part of the motor and also cools the oil cooling circulating oil channel passing through the inside of the motor, achieving the effect of cooling the oil cooling system while cooling the motor. The two cooling systems are independent of each other and interact with each other, improving the heat dissipation performance of the motor; the reduction gearbox part uses the oil cooling system, and the reduction gears are immersed in the cooling oil. When the motor system is running, it can effectively reduce noise, improve the lubrication performance of the reduction gearbox, has a simple structure, good cooling effect, low noise, and high motor driving efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 is a schematic plan structure diagram of the motor cooling device according to an embodiment of the present invention; Figure 2 is a schematic plan structure diagram of the circulating oil channel of the motor cooling device according to an embodiment of the present invention; Figure 3 is a schematic plan structure diagram of the circulating water channel of the motor cooling device according to an embodiment of the present invention; Figure 4 is a schematic three - dimensional structure diagram of the front end cover of the housing of the motor cooling device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0007] As shown in the figure, a motor cooling device includes a motor housing 5. The front and rear ends of the housing 5 are hermetically connected through a front housing cover 1 and a rear housing cover 6. A motor shaft 2 is provided at the center of the housing 5. The front and rear ends of the motor shaft 2 are coaxially installed on the front housing cover 1 and the rear housing cover 6 respectively. A rotor 8 is installed on the motor shaft 2, and a stator 9 is installed on the inner wall of the housing 5. A reduction gear 3 for installing a reduction gearbox is further provided at the front end of the motor shaft 2. A motor front cover 4 is also provided inside the front housing cover 1. The front housing cover 1 and the motor front cover 4 are mutually matched through a rib groove structure to form a gear chamber 204 of the reduction gearbox. At the top corners of the housing 5, a "pin" - shaped water channel is arranged longitudinally along the housing. The top water channel 101 of the "pin" - shaped is the water inlet channel, and the two side water channels 102 at the top are the water return channels. A motor rear cover 7 is provided inside the rear housing cover 6. Water inlet holes and water outlet holes are provided on the rear housing cover 6 and the motor rear cover 7. Grooved water channels are provided on the inner walls of the motor rear cover 7 and the motor front cover 4. The water inlet holes and water outlet holes are respectively connected to the water inlet channel 101 and the water return channel 102 at the four corners of the housing 5. The longitudinal water inlet channel 101 and water return channel 102 at the top corners of the housing 5 form a circulating water channel through the inner water channels of the motor rear cover 7 and the motor front cover 4. An oil passage 103 is provided at the middle position of the "pin" - shaped water channel at at least one housing top corner. The motor shaft 2 has a hollow inner cavity with openings provided at the front and rear ends of the motor shaft 2. An oil injection hole 201 is provided on the outer wall of the front housing cover 1, and an oil channel 202 is provided inside. A gear chamber oil injection hole 203 is provided at the lower part of the wall of the gear chamber 204 of the reduction gearbox. An oil channel is also provided on the rear housing cover 6. The openings at the front and rear ends of the hollow inner cavity of the motor shaft 2 are respectively connected to the oil channels on the rear housing cover 6 and the front housing cover 1. The openings at the front and rear ends of the hollow inner cavity of the motor shaft 2 are connected to the oil passage 103 on the housing 5 through the oil channels on the rear housing cover 6 and the front housing cover 1 to form a circulating oil channel. A oil pump is provided at the connection between the oil channel on the front housing cover 1 and the oil passage 103 at the top corner of the housing 5. The oil pump can provide circulating power for the cooling oil in the circulating oil channel. A motor rear cover 7 is also provided inside the rear housing cover 6. The grooved water channel is provided on the inner wall of the motor rear cover 7. A number of oil storage grooves 205 are provided around the gear chamber 204 on the inner wall of the front housing cover 1. The hollow inner cavity of the motor shaft 2 has a step. The motor housing 5 is rectangular.

[0008] The motor cooling device system of the present invention includes two parts: a motor and a reduction gearbox. It uses two cooling systems, water cooling and oil cooling, to cool the entire motor system simultaneously. The oil cooling system mainly cools the reduction gearbox part and cools the motor rotor part through a circulating oil channel. The water cooling system mainly cools the motor stator part. The part of the circulating oil channel located on the housing is in the middle position of the "pin" - shaped water channel. The cooling water in the "pin" - shaped water channel cools the motor stator and also cools the oil - cooling circulating oil channel passing through the motor. By cooling the motor with water cooling and simultaneously cooling the oil cooling system, the two cooling systems are independent of each other and interact with each other to jointly form the cooling system of the motor system of the present invention, optimizing the heat dissipation performance of the motor. Since the reduction gearbox part in the motor system uses an oil cooling system and the reduction gears are immersed in the cooling oil, when the motor system is running, it can effectively reduce noise and at the same time lubricate the reduction gearbox. The oil filling hole is not sealed, and the reduction gears are immersed in the cooling oil. To ensure that the cooling oil is not thrown out when the reduction gearbox is working, there is a splash - proof oil channel inside the reduction gearbox housing. The reduction gears are placed in the gear chamber. The oil filling hole of the gear chamber is not the same hole as the oil filling hole of the reduction gearbox, and the cooling oil is only injected to 3 / 4 of the reduction gearbox. When the gears in the reduction gearbox rotate, the cooling oil will only be thrown into the splash - proof oil channel and will not be thrown out of the reduction gearbox. The motor stator part is cooled by the water cooling system, and the rotor is cooled by the oil cooling system, that is, the stator is water - cooled and the rotor is oil - cooled. The main heat - generating parts during the operation of the motor are effectively cooled, significantly improving the heat dissipation performance of the motor and the working efficiency of the motor.

[0009] The front - end cover 1 of the housing, the motor shaft 2, the reduction gears 3, the front - end cover 4 of the motor, the housing 5, the rear - end cover 7 of the motor, the rear - end cover 6 of the housing, the rotor 8, the stator 9, and the water / oil channel together form a rectangular motor. The front - end cover 1 of the housing, the reduction gears 3, and the front - end cover 4 of the motor together form the reduction gearbox part. The front - end cover 4 of the motor is both the rear - end cover of the reduction gearbox and the front - end cover of the motor. The water / oil channels are at the four corners of the housing 5. Three independent straight - through water channels are arranged in a "pin" - shaped triangle at each corner. There is an oil - flow channel in the middle of three "pin" - shaped water channels at one of the corners. The front - end cover 4 of the motor, the housing 5, the rear - end cover 7 of the motor, and the rear - end cover 6 of the housing form the motor. The motor and the reduction gearbox share a motor shaft 2. The inside of the motor shaft 2 is hollow to form a hollow inner cavity, and this hollow inner cavity part is a part of the circulating oil channel. There are water inlet and outlet holes on the rear - end cover 7 of the motor connected to the water inlet channels 101 at the four corners of the housing 5, and an oil - flow channel at one of the top corners is connected to the oil - flow channel 103 on the housing and the hollow inner cavity of the motor shaft that serves as an oil channel.

[0010] The oil cooling system of the motor cooling device of the present invention is as follows: through the oil inlet hole 201 in the speed reducer part, cooling oil is injected into the gear chamber of the speed reducer, so that the reduction gears are immersed in the cooling oil. Through the oil pump arranged at a corner of the speed reducer, the cooling oil in the speed reducer is pumped into the oil passage on the housing. The cooling oil flows through the oil passage on the housing, the oil passage of the rear end cover of the housing, and the hollow inner cavity of the motor shaft in sequence, and then returns to the speed reducer, forming a complete circulating oil passage. In this circulating oil passage, the cooling oil cools the reduction gears 3 in the speed reducer and plays a lubricating role. When passing through the motor housing 5, the oil passage is surrounded by the water passages 101 and 102 in a triangular shape. At this time, the cooling water in the water passage cools the oil passage. The cooled cooling oil enters the hollow inner cavity of the motor shaft 2 through the rear end cover 7 of the motor, cools the rotor of the motor, and finally returns to the speed reducer to complete an oil cooling cycle. The hollow inner cavity of the motor shaft 2 has steps, making the oil passage cooling space in the motor shaft 2 larger and further improving the cooling effect.

[0011] For the water cooling system of the motor cooling device of the present invention, there are 3 holes arranged in a "pin" - shaped triangle at the four corners of the rear end cover of the motor as the water circulation channels. There are three longitudinally through - holes arranged in a "pin" - shaped triangle at each of the four corners of the motor housing, forming the water inlet channel and the water outlet channel of the housing. The positions and shapes of the holes on the rear end cover of the motor and the through - holes on the housing are adapted to each other. Cooling water enters from the water inlet hole on the rear end cover of the motor, flows along the groove water passage on the rear end cover of the motor to the positions corresponding to the water inlet channels of the housing at the four corners, and then enters the corresponding water inlet channels of the housing. It flows straight along the water inlet channel of the motor housing to the front end cover of the motor, flows along the groove water passage on the front end cover of the motor to the positions corresponding to the water return channels of the housing at the four corners, and then enters the corresponding water return channels of the housing. It flows straight along the water return channel of the motor housing to the rear end cover of the motor, and flows along the groove water passage on the rear end cover of the motor to flow out through the water outlet hole, completing a water cooling cycle. At one of the corners of the housing, in addition to the through - holes arranged in a triangle, there is another through - hole, that is, the oil passage. The oil passage is surrounded by the other three water - passage through - holes in a triangle. Therefore, the water cooling system cools the oil passage while cooling the motor.

[0012] The front end cover of the motor cooling device housing of the present invention includes an oil injection hole 201, an anti-splash oil channel 202, a gear chamber oil injection hole 203, and a reduction gear chamber 204; a plurality of oil storage grooves 205 are provided around the gear chamber 204: firstly, to reduce weight; secondly, to allow cooling oil to be injected into the grooves to cool the reduction gear chamber 204 externally; when cooling oil enters from the oil injection hole 201, it enters the plurality of oil storage grooves 205 outside the reduction gear chamber 204 through the anti-splash oil channel 202, and simultaneously enters the reduction gear chamber 204 through the gear chamber oil injection hole 203; when the reduction gear 3 rotates at high speed, the temperature inside the reduction gear chamber 204 will rise and a vacuum state will be formed, causing the cooling oil to flow out from the gear... The coolant splashes out of the gearbox oil filling hole 203. To solve this problem, this embodiment requires that the coolant is only injected into 3 / 4 of the gearbox gear chamber 204. At the same time, the oil filling hole 201, which is connected to the outside, is not the same hole as the gearbox oil filling hole 203. The coolant splashing out of the gearbox gear chamber 204 will only splash out of the gearbox oil filling hole 203, flow into the anti-splash oil channel 202 and return to the oil storage groove 205 outside the gearbox gear chamber 204. At the same time, because only 3 / 4 of the coolant is injected, the coolant in the oil storage groove 205 outside the gearbox gear chamber 204 is 1 / 4 of the distance from the oil filling hole 201, so the coolant will not splash out of the oil filling hole 201.

[0013] The motor cooling device of this invention employs two cooling systems, water cooling and oil cooling, to simultaneously cool the entire motor system. The oil cooling system primarily cools the gearbox and also cools the internal rotor of the motor through circulating oil channels. The water cooling system primarily cools the motor stator and also cools the circulating oil channels passing through the motor, achieving the effect of cooling the oil cooling system while simultaneously cooling the motor. The two cooling systems are independent yet interact with each other, improving the motor's heat dissipation performance. The gearbox uses an oil cooling system, with the reduction gears immersed in cooling oil. During motor operation, this effectively reduces noise, improves lubrication of the gearbox, and results in a simple structure, good cooling effect, low noise, and high motor drive efficiency.

Claims

1. A composite cooling device for an electric motor, comprising a motor housing (5), the front and rear ends of the housing (5) being closedly connected by a front end cover (1) and a rear end cover (6), a motor shaft (2) being disposed at the center of the housing (5), the front and rear ends of the motor shaft (2) being coaxially mounted on the front end cover (1) and the rear end cover (6) of the housing respectively, a rotor (8) being mounted on the motor shaft (2), and a stator (9) being mounted on the inner wall of the housing (5); a reduction gearbox for mounting a reduction gear (3) is also disposed at the front end of the motor shaft (2), characterized in that: A motor front end cover (4) is further arranged inside the front end cover (1) of the housing. A gear chamber (204) of the reduction gearbox is formed by the mutual cooperation of the front end cover (1) of the housing and the motor front end cover (4) through a rib groove structure; At the top corners of the housing (5), a water channel in a "pin" shape is arranged longitudinally along the housing. The top water channel (101) of the "pin" shape is the water inlet channel, and the two side water channels (102) at the top are the water return channels. A motor rear end cover (7) is arranged inside the rear end cover (6) of the housing. Water inlet holes and water outlet holes are arranged on the rear end cover (6) of the housing and the motor rear end cover (7). Grooved water channels are arranged on the inner walls of the motor rear end cover (7) and the motor front end cover (4). The water inlet holes and water outlet holes are respectively connected to the water inlet channels (101) and water return channels (102) at the four corners of the housing (5) through the grooved water channels. The longitudinal water inlet channels (101) and water return channels (102) at the top corners of the housing (5) form a circulating water channel through the grooved water channels inside the motor rear end cover (7) and the motor front end cover (4); An oil channel (103) is arranged at the middle position of the "pin" shape water channel at at least one top corner of the housing; The motor shaft (2) has a hollow inner cavity, and openings are arranged at the front and rear ends of the hollow inner cavity of the motor shaft (2). An oil injection hole (201) is arranged on the outer wall of the front end cover (1) of the housing, and an oil channel (202) is arranged inside. An oil injection hole (203) for the gear chamber is arranged at the lower part of the wall of the gear chamber (204) of the reduction gearbox; An oil channel is also arranged on the rear end cover (6) of the housing; The openings at the front and rear ends of the hollow inner cavity of the motor shaft (2) are respectively connected to the oil channels on the rear end cover (6) and the front end cover (1) of the housing. The hollow inner cavity of the motor shaft (2), the oil channel on the rear end cover (6) of the housing, and the oil channel on the front end cover (1) of the housing are connected to the oil channel (103) at the top corner of the housing (5) to form a circulating oil channel; A oil pump is arranged at the connection between the oil channel on the front end cover (1) of the housing and the oil channel (103) at the top corner of the housing (5), and the oil pump can provide circulating power for the cooling oil in the circulating oil channel.

2. The motor cooling device according to claim 1, characterized in that: A number of oil storage grooves (205) are arranged around the gear chamber (204) on the inner wall of the front end cover (1) of the housing.

3. The motor cooling device according to claim 1, characterized in that: The hollow inner cavity of the motor shaft (2) has steps.

4. The motor cooling device according to claim 1, characterized in that: The motor housing (5) is rectangular.

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