Cooling device

Abstract

To cool a plurality of parts of a cooled object by variably changing an injection direction from injection holes while suppressing the installation number of the injection holes, in a cooling device of a double cylinder structure.SOLUTION: A nozzle of a cooling device for cooling a cooled object includes: a first inclined injection hole penetrating through an outer cylinder in a state of being inclined in a prescribed direction to a radial direction of the outer cylinder; and a second inclined injection hole penetrating through an inner cylinder in a state of being inclined to a prescribed direction to a radial direction. The inner cylinder axially slides relatively to the outer cylinder against energization force of an elastic member by a pressure of a cooling liquid introduced to the inside of the inner cylinder, and a relative position of the inner cylinder to the outer cylinder is changed by change of the pressure of the cooling liquid introduced to the inside of the inner cylinder. The injection direction of the cooling liquid injected through the first inclined injection hole and the second inclined injection hole is variable by changing an overlapping area of the first inclined injection hole and the second inclined injection hole, and a communication direction of the first inclined injection hole and the second inclined injection hole.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a cooling device.

Background Art

[0002] For example, Patent Document 1 discloses a cooling structure for cooling a motor stator and a generator stator. The cooling structure according to Patent Document 1 has pipes for injecting a coolant to the coil ends of the motor stator and the generator stator.

[0003] Inside each pipe of the cooling structure according to Patent Document 1, a sliding pipe that slides on the inner peripheral surface is arranged. The pipe is provided with holes for forming a first drip lower part, and the sliding pipe is provided with holes for forming a first drip lower part at the same axial distance as the holes of the pipe. Further, inside each pipe, a spring for biasing the sliding pipe in a direction to close the first drip lower part is provided.

[0004] When the pressure of the coolant passing through the inside of the sliding pipe is low, since the holes of the pipe and the holes of the sliding pipe are displaced in the axial direction, the first drip lower part is in a closed state. Further, when the pressure of the coolant passing through the inside of the sliding pipe becomes high and the sliding pipe slides against the biasing force of the spring, the holes of the pipe and the holes of the sliding pipe coincide in the axial direction, so that the first drip lower part is in an open state.

[0005] Thus, according to the cooling structure according to Patent Document 1, the supply and supply stop of the coolant to the generator stator can be switched by opening and closing each set of holes (first drip lower part) formed in the double-structured pipe by the pressure of the coolant supplied into the sliding pipe.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

[0007] However, in the cooling structure described in Patent Document 1, since the direction of coolant injection is only one direction, even if the communication state of each set of holes is switched, only the same part of the stator can be cooled.

[0008] To switch between two different locations on the stator for cooling, it is necessary to create yet another set of holes in the double-walled pipe. In that case, the structure of the double-walled pipe becomes more complex, the number of manufacturing steps increases, and the cost of the double-walled pipe increases.

[0009] Furthermore, when switching between two different, adjacent locations on the stator for cooling, it is necessary to place two sets of holes in the double-walled pipe at these two different locations. In this case, depending on the axial distance between the two sets of holes, all the holes may connect when the sliding pipe slides inside the pipe, making it impossible to switch between cooling two different locations on the stator. Thus, when switching between two different locations on the stator for cooling, there were sometimes constraints on the arrangement of the holes.

[0010] Therefore, the present invention aims to provide a cooling device with a double-cylinder structure that can cool multiple locations on an object to be cooled by reducing the number of injection holes while varying the direction of injection from the injection holes. [Means for solving the problem]

[0011] To solve the above problems, the cooling device of the present invention A cooling device for cooling an object to be cooled, A pump that supplies coolant, A nozzle positioned opposite the object to be cooled, which sprays the coolant supplied from the pump toward the object to be cooled, Equipped with, The aforementioned nozzle is Outer cylinder and An inner cylinder is provided inside the outer cylinder so as to be slidable in the axial direction of the outer cylinder, and into which the cooling liquid is introduced. An elastic member connected between the outer cylinder and the inner cylinder, which biases the inner cylinder in the axial direction, The outer cylinder has a first inclined injection hole formed through it at an angle in a predetermined direction with respect to the radial direction of the outer cylinder, In the inner cylinder, a second inclined injection hole is formed through the cylinder, inclined in a predetermined direction with respect to the radial direction, Equipped with, The inner cylinder slides relative to the outer cylinder in the axial direction against the biasing force of the elastic member due to the pressure of the coolant introduced into the inner cylinder, The configuration is such that the injection direction of the coolant injected through the first and second inclined injection holes is variable, as the relative position of the inner cylinder with respect to the outer cylinder changes due to a change in the pressure of the coolant introduced into the inner cylinder, and the overlapping area of ​​the first and second inclined injection holes and the direction in which the first and second inclined injection holes communicate change. [Effects of the Invention]

[0012] According to the present invention, in a double-cylinder cooling device, it is possible to cool multiple locations on an object to be cooled by varying the direction of injection from the injection holes while suppressing the number of injection holes. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 is a schematic diagram showing the configuration of the vehicle. [Figure 2] Figure 2 is a schematic cross-sectional view showing the configuration of the cooling device for the motor at low rotational speed according to this embodiment. [Figure 3] Figure 3A is a schematic cross-sectional view near the injection hole for the second coil end when the inner cylinder is positioned in the first relative position. Figure 3B is a schematic cross-sectional view near the injection hole for the core when the inner cylinder is positioned in the first relative position. Figure 3C is a schematic cross-sectional view near the injection hole for the first coil end when the inner cylinder is positioned in the first relative position. [Figure 4] FIG. 4 is a schematic cross-sectional view showing the configuration of the cooling device during high rotation of the motor according to the present embodiment. [Figure 5] FIG. 5A is a schematic cross-sectional view near the injection hole for the second coil end when the inner cylinder is disposed at the second relative position. FIG. 5B is a schematic cross-sectional view near the injection hole for the core when the inner cylinder is disposed at the second relative position. FIG. 5C is a schematic cross-sectional view near the injection hole for the first coil end when the inner cylinder is disposed at the second relative position. MODE FOR CARRYING OUT THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Specific dimensions, materials, numerical values, etc. shown in such embodiments are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same functions and configurations are denoted by the same reference numerals to omit redundant description, and elements not directly related to the present invention are not shown.

[0015] FIG. 1 is a schematic configuration diagram showing the configuration of a vehicle 100 according to the present embodiment. In the present embodiment, the vehicle 100 is an electric vehicle having a motor as a drive source. However, the present invention is not limited thereto, and the vehicle 100 may be a hybrid vehicle having an engine and a motor as power sources. The vehicle 100 of the present embodiment enables both four-wheel drive (4WD) traveling in which both front and rear wheels are driven and two-wheel drive (2WD) traveling in which only the front wheels are driven.

[0016] The vehicle 100 includes a motor 110, an inverter 112, a battery 114, a transmission 116, an electronic control unit (hereinafter simply referred to as ECU) 118, a propeller shaft 120, a front differential gear 122, a front drive shaft 124, front wheels 126, an electronic control coupling 128, a rear differential gear 130, a rear drive shaft 132, rear wheels 134, a transmission case 136, and a cooling device 200.

[0017] The motor 110 obtains driving force from the electric power supplied from the battery 114 via the inverter 112, and transmits the obtained driving force to the transmission 116. Also, the motor 110 functions as a generator at the timing when it is not receiving power supply. The electric power generated by the motor 110 is stored in the battery 114 via the inverter 112. Also, the inverter 112 is connected to the ECU 118, and the supply power, that is, the driving force of the motor 110 is adjusted based on the control command of the ECU 118.

[0018] The driving force output from the motor 110 is adjusted in torque, rotational speed, and rotational direction by the transmission 116 and transmitted to the propeller shaft 120, and further transmitted to the front wheels 126 via the front differential gear 122 and the front drive shaft 124. Also, during 4WD driving, the driving force output from the transmission 116 is also transmitted to the rear wheels 134 via the electronic control coupling 128, the rear differential gear 130, and the rear drive shaft 132. Here, the front wheels 126 obtain the driving force directly from the transmission 116, and the rear wheels 134 obtain the driving force via the electronic control coupling 128. However, it is also possible to transmit the driving force directly from the transmission 116 to the rear wheels 134 and transmit the driving force to the front wheels 126 via the electronic control coupling 128.

[0019] The transmission case 136 houses the motor 110, the transmission 116, and the cooling device 200. The transmission case 136 has an oil pan (not shown), and the oil pan stores transmission oil (hereinafter simply referred to as oil) for cooling and lubricating each member inside the transmission case 136.

[0020] Figure 2 is a schematic cross-sectional view showing the configuration of the cooling device 200 of the motor 110 according to this embodiment at low rotation speeds. As shown in Figure 2, the motor 110 has a stator 150 (object to be cooled) and a rotor (not shown). The stator 150 comprises a core 160 (second object to be cooled) and a coil 170. When power is supplied to the coil 170, the stator 150 generates a force to rotate the rotor.

[0021] The core 160 is formed in a cylindrical shape and is positioned concentrically with the central axis of the rotor. Teeth (not shown) are arranged at equal intervals in the circumferential direction on the inner surface of the core 160. The coil 170 is wound around the multiple teeth. A portion of the coil 170 wound around the teeth protrudes from both ends of the core 160 in the direction of the central axis of the core 160. Hereinafter, the coil 170 that protrudes from one end of the core 160 will be called the first coil end 170a, and the coil 170 that protrudes from the other end will be called the second coil end 170b.

[0022] As shown in Figures 1 and 2, the cooling device 200 includes a nozzle 210 and an electric oil pump (hereinafter simply referred to as EOP) 250. The cooling device 200 is a device for cooling the stator 150, which is the object to be cooled. The nozzle 210 is positioned opposite the upper side of the stator 150. The EOP 250 supplies oil (coolant) stored in the oil pan of the transmission case 136 to the nozzle 210. The nozzle 210 sprays the oil supplied from the EOP 250 toward the stator 150. The oil sprayed toward the stator 150 from the nozzle 210 can cool the stator 150.

[0023] The EOP250 is connected to the ECU118 and adjusts the oil volume and pressure supplied to the nozzle 210 based on control commands from the ECU118. The ECU118 controls the EOP250 so that, for example, the oil volume and pressure increase as the rotational speed of the motor 110 increases.

[0024] As shown in Figure 2, the nozzle 210 comprises an outer cylinder 220, an inner cylinder 230, and a spring 240 (elastic member). The outer cylinder 220 and the inner cylinder 230 have a closed-bottom cylindrical shape with one end closed. Specifically, one end of the outer cylinder 220 has a closed portion 220a, and the other end of the outer cylinder 220 has an opening 220b. Similarly, one end of the inner cylinder 230 has a closed portion 230a, and the other end of the inner cylinder 230 has an opening 230b. The inner cylinder 230 and the spring 240 are housed inside the outer cylinder 220. The central axes of the outer cylinder 220 and the inner cylinder 230 are positioned approximately parallel to the central axes of the rotor and core 160.

[0025] The inner cylinder 230 is slidably mounted inside the outer cylinder 220 in the direction of the outer cylinder 220's central axis. The closing portion 230a of the inner cylinder 230 is located on one end of the outer cylinder 220 and is positioned near the closing portion 230a of the outer cylinder 220. Oil supplied from the EOP 250 is introduced into the interior of the inner cylinder 230.

[0026] The spring 240 is connected between the closing portion 220a of the outer cylinder 220 and the closing portion 230a of the inner cylinder 230, and biases the inner cylinder 230 in the axial direction. Specifically, the spring 240 biases the closing portion 230a of the inner cylinder 230 in a direction that separates it from the closing portion 220a of the outer cylinder 220.

[0027] The state of the spring 240 changes depending on the pressure of the oil supplied to the inner cylinder 230. When the oil pressure becomes greater than the biasing force of the spring 240, the spring 240 is pressed against the closed portion 230a of the inner cylinder 230, changing from an extended state to a contracted state. When the oil pressure becomes less than the biasing force of the spring 240, the spring 240 biases the closed portion 220a of the inner cylinder 230, changing from a contracted state to an extended state.

[0028] On the side surface of the outer cylinder 220, a first coil end injection hole 222 (first inclined injection hole), a second coil end injection hole 224 (fifth injection hole), and a core injection hole 226 (third injection hole) are formed. The first coil end injection hole 222, the second coil end injection hole 224, and the core injection hole 226 are formed aligned along the central axis of the outer cylinder 220.

[0029] The first coil end injection hole 222 is located on one end side of the outer cylinder 220, more so than the second coil end injection hole 224 and the core injection hole 226. The first coil end injection hole 222 is positioned radially opposite the first coil end 170a (first object to be cooled) of the stator 150. The first coil end injection hole 222 is formed to penetrate the outer cylinder 220, inclined in a predetermined direction with respect to the radial direction.

[0030] The injection holes 224 for the second coil end are located on the other end of the outer cylinder 220, further away from the injection holes 222 for the first coil end and the injection holes 226 for the core. The injection holes 224 for the second coil end are positioned radially opposite the second coil end 170b (third object to be cooled) of the stator 150. The injection holes 224 for the second coil end are formed to penetrate the outer cylinder 220 radially.

[0031] The core injection holes 226 are provided between the first coil end injection holes 222 and the second coil end injection holes 224. The core injection holes 226 are positioned radially opposite the core 160 (second cooling target) of the stator 150. The core injection holes 226 are formed to penetrate the outer cylinder 220 in the radial direction.

[0032] On the side surface of the inner cylinder 230, a first coil end injection hole 232 (second inclined injection hole), a second coil end injection hole 234 (sixth injection hole), and a core injection hole 236 (fourth injection hole) are formed. The first coil end injection hole 232, the second coil end injection hole 234, and the core injection hole 236 are formed aligned along the central axis of the inner cylinder 230.

[0033] The circumferential positions of the first coil end injection holes 232, the second coil end injection holes 234, and the core injection holes 236 of the inner cylinder 230 roughly coincide with the circumferential positions of the first coil end injection holes 222, the second coil end injection holes 224, and the core injection holes 226 of the outer cylinder 220. In other words, the first coil end injection holes 232, the second coil end injection holes 234, and the core injection holes 236 of the inner cylinder 230 are provided in the same phase as the first coil end injection holes 222, the second coil end injection holes 224, and the core injection holes 226 of the outer cylinder 220.

[0034] The first coil end injection hole 232 is located on one end side of the inner cylinder 230, compared to the second coil end injection hole 234 and the core injection hole 236. The first coil end injection hole 232 is positioned radially opposite to the first coil end 170a of the stator 150. The first coil end injection hole 232 is formed to penetrate the inner cylinder 230, inclined in a predetermined direction with respect to the radial direction. Here, the inclination direction of the first coil end injection hole 222 is the same as the inclination direction of the first coil end injection hole 232, and the inclination angle is also the same. The core 160 is positioned opposite the first coil end injection holes 222 and 232 in a direction inclined radially in that predetermined direction.

[0035] The injection hole 234 for the second coil end is located on the other end side of the inner cylinder 230, further than the injection hole 232 for the first coil end and the injection hole 236 for the core. The injection hole 234 for the second coil end is positioned radially opposite to the second coil end 170b of the stator 150. The injection hole 234 for the second coil end is formed to penetrate the inner cylinder 230 radially.

[0036] The core injection hole 236 is provided between the first coil end injection hole 232 and the second coil end injection hole 234. The core injection hole 236 is positioned radially opposite the core 160 of the stator 150. The core injection hole 236 is formed to penetrate radially through the inner cylinder 230.

[0037] The inner cylinder 230 slides relative to the outer cylinder 220 in the axial direction due to the increasing pressure of the oil introduced into the inner cylinder 230, against the biasing force of the spring 240. Specifically, when the oil pressure is greater than the biasing force of the spring 240, the oil pressure causes the closed portion 230a of the inner cylinder 230 to slide toward the closed portion 230a of the outer cylinder 220, against the biasing force of the spring 240. The direction in which the inner cylinder 230 moves in the axial direction at this time is defined as the positive direction in the axial direction. Conversely, when the biasing force of the spring 240 is greater than the oil pressure, the direction in which the closed portion 230a of the inner cylinder 230 moves toward the closed portion 220a of the outer cylinder 220 due to the biasing force of the spring 240 is defined as the negative direction in the axial direction. The injection holes 222 and 232 for the first coil end are inclined toward the negative direction from the inside outward.

[0038] Here, a position restricting portion 228 is provided inside the outer cylinder 220. The position restricting portion 228 is provided between the closing portion 220a of the outer cylinder 220 and the closing portion 230a of the inner cylinder 230. The position restricting portion 228 is configured to be able to contact the closing portion 220a of the inner cylinder 230, and by contacting the closing portion 230a, it restricts the movement of the inner cylinder 230 in the direction of the central axis.

[0039] As a result, even if the pressure of the oil introduced into the inner cylinder 230 becomes too high, the position restricting unit 228 restricts the movement of the inner cylinder 230 in the central axis direction, thereby positioning the relative position of the inner cylinder 230 with respect to the outer cylinder 220 at a predetermined position.

[0040] On the other hand, when the biasing force of the spring 240 is greater than the oil pressure, the closing portion 230a of the inner cylinder 230 slides in a direction away from the closing portion 220a of the outer cylinder 220, relative to the biasing force of the spring 240.

[0041] As shown in Figure 2, when the oil pressure is a first pressure (below a predetermined pressure), the inner cylinder 230 is positioned at a first relative position with respect to the outer cylinder 220. Also, as will be described later, when the oil pressure is a second pressure (above a predetermined pressure), the inner cylinder 230 is positioned at a second relative position with respect to the outer cylinder 220 (see Figure 4). The first relative position is located on the other end side of the outer cylinder 220 than the second relative position. The second relative position is located on the one end side of the outer cylinder 220 than the first relative position. In other words, the first relative position is located on the negative side of the extension of the spring 240 than the second relative position. The second relative position is located on the positive side of the contraction of the spring 240 than the first relative position.

[0042] Figure 3A is a schematic cross-sectional view of the vicinity of the injection holes 224 and 234 for the second coil end when the inner cylinder 230 is positioned in the first relative position. Figure 3B is a schematic cross-sectional view of the vicinity of the injection holes 226 and 236 for the core when the inner cylinder 230 is positioned in the first relative position. Figure 3C is a schematic cross-sectional view of the vicinity of the injection holes 222 and 232 for the first coil end when the inner cylinder 230 is positioned in the first relative position.

[0043] As shown in Figure 3A, the injection hole 224 for the second coil end of the outer cylinder 220 has an inner opening 224a and an outer opening 224b. Similarly, the injection hole 234 for the second coil end of the inner cylinder 230 has an inner opening 234a and an outer opening 234b.

[0044] When the inner cylinder 230 is positioned in the first relative position, a portion of the second coil end injection hole 224 of the outer cylinder 220 overlaps with a portion of the second coil end injection hole 234 of the inner cylinder 230, and they communicate radially. More specifically, when the inner cylinder 230 is positioned in the first relative position, a portion of the outer opening 234b of the second coil end injection hole 234 of the inner cylinder 230 overlaps with a portion of the inner opening 224a of the second coil end injection hole 224 of the outer cylinder 220.

[0045] As shown in Figure 3B, the core injection hole 226 of the outer cylinder 220 has an inner opening 226a and an outer opening 226b. Similarly, the core injection hole 236 of the inner cylinder 230 has an inner opening 236a and an outer opening 236b.

[0046] When the inner cylinder 230 is positioned in the first relative position, the core injection holes 226 of the outer cylinder 220 do not overlap radially with and communicate with the core injection holes 236 of the inner cylinder 230. More specifically, when the inner cylinder 230 is positioned in the first relative position, the outer opening 236b of the core injection holes 236 of the inner cylinder 230 does not overlap radially with the inner opening 226a of the core injection holes 226 of the outer cylinder 220.

[0047] As shown in Figure 3C, the injection hole 222 for the first coil end of the outer cylinder 220 has an inner opening 222a and an outer opening 222b. Similarly, the injection hole 232 for the first coil end of the inner cylinder 230 has an inner opening 232a and an outer opening 232b.

[0048] When the inner cylinder 230 is positioned in the first relative position, a portion of the first coil end injection hole 222 of the outer cylinder 220 overlaps with a portion of the first coil end injection hole 232 of the inner cylinder 230, and they communicate radially. More specifically, when the inner cylinder 230 is positioned in the first relative position, a portion of the outer opening 232b of the first coil end injection hole 232 of the inner cylinder 230 overlaps with a portion of the inner opening 222a of the first coil end injection hole 222 of the outer cylinder 220.

[0049] As shown in Figure 3A, when the inner cylinder 230 is positioned in the first relative position, a portion of the second coil end injection hole 224 of the outer cylinder 220 overlaps with a portion of the second coil end injection hole 234 of the inner cylinder 230, thereby communicating radially. As a result, the nozzle 210 can inject oil into the second coil end 170b through the second coil end injection holes 224 and 234, as indicated by the white arrows in Figure 2. At this time, the radial direction in which the oil flows through the second coil end injection holes 224 and 234 is defined as the direction in which the second coil end injection holes 224 and 234 communicate.

[0050] As shown in Figure 3B, when the inner cylinder 230 is positioned in the first relative position, the core injection holes 226 of the outer cylinder 220 do not overlap radially with the core injection holes 236 of the inner cylinder 230 and do not communicate with them. Therefore, as shown in Figure 2, the injection of oil into the core 160 through the core injection holes 226 and 236 is stopped.

[0051] As shown in Figure 3C, when the inner cylinder 230 is positioned in the first relative position, a portion of the first coil end injection hole 222 of the outer cylinder 220 overlaps with a portion of the first coil end injection hole 232 of the inner cylinder 230, thereby communicating radially. As a result, the nozzle 210 can inject oil into the first coil end 170a through the first coil end injection holes 222 and 232, as indicated by the white arrows in Figure 2.

[0052] As described above, the ECU 118 controls the EOP 250 so that the oil volume and oil pressure increase as the rotational speed of the motor 110 increases. Here, at low rotational speeds of the motor 110, the heat generated by the core 160 of the stator 150 is below the threshold, while the heat generated by the coil 170 is above the threshold.

[0053] The ECU 118 controls the EOP 250 so that the oil pressure becomes a first pressure, which is below a predetermined pressure, when the motor 110 is rotating at low speeds. When the oil pressure becomes a first pressure, which is below the predetermined pressure, the nozzle 210 injects oil into the first coil end 170a and the second coil end 170b, as explained in Figures 2, 3A to 3C, and stops injecting oil into the core 160.

[0054] This allows oil to be injected only into the first coil end 170a and the second coil end 170b, which generate more heat than a threshold and require cooling when the motor 110 is rotating at low speeds, thereby enabling cooling.

[0055] Figure 4 is a schematic cross-sectional view showing the configuration of the cooling device 200 when the motor 110 is rotating at high speed according to this embodiment. As shown in Figure 4, when the motor 110 is rotating at high speed, the oil pressure becomes a second pressure, which is higher than a predetermined pressure. When the oil pressure is the second pressure, the closing portion 220a of the inner cylinder 230 comes into contact with the position restricting portion 228 of the outer cylinder 220, and the inner cylinder 230 is positioned at a second relative position with respect to the outer cylinder 220. The second relative position is located closer to one end of the outer cylinder 220 than the first relative position. In other words, the second relative position is located on the positive direction side where the spring 240 contracts, compared to the first relative position.

[0056] Figure 5A is a schematic cross-sectional view of the vicinity of the injection holes 224 and 234 for the second coil end when the inner cylinder 230 is positioned in the second relative position. Figure 5B is a schematic cross-sectional view of the vicinity of the injection holes 226 and 236 for the core when the inner cylinder 230 is positioned in the second relative position. Figure 5C is a schematic cross-sectional view of the vicinity of the injection holes 222 and 232 for the first coil end when the inner cylinder 230 is positioned in the second relative position.

[0057] As shown in Figure 5A, when the inner cylinder 230 is positioned in the second relative position, the second coil end injection hole 224 of the outer cylinder 220 overlaps with the second coil end injection hole 234 of the inner cylinder 230 and communicates radially with it. More specifically, when the inner cylinder 230 is positioned in the second relative position, the entire outer opening 234b of the second coil end injection hole 234 of the inner cylinder 230 overlaps with the entire inner opening 224a of the second coil end injection hole 224 of the outer cylinder 220.

[0058] As shown in Figure 5B, when the inner cylinder 230 is positioned in the second relative position, the core injection holes 226 of the outer cylinder 220 overlap radially with and communicate with the core injection holes 236 of the inner cylinder 230. More specifically, when the inner cylinder 230 is positioned in the second relative position, the entire outer opening 236b of the core injection holes 236 of the inner cylinder 230 overlaps with the entire inner opening 226a of the core injection holes 226 of the outer cylinder 220.

[0059] As shown in Figure 5C, when the inner cylinder 230 is positioned in the second relative position, the first coil end injection hole 222 of the outer cylinder 220 overlaps with the first coil end injection hole 232 of the inner cylinder 230 and communicates radially with it. More specifically, when the inner cylinder 230 is positioned in the second relative position, the entire outer opening 232b of the first coil end injection hole 232 of the inner cylinder 230 overlaps with the entire inner opening 222a of the first coil end injection hole 222 of the outer cylinder 220.

[0060] The inclination direction of the injection holes 222 and 232 for the first coil ends relative to the radial direction is the negative direction in which the spring 240 extends, when the direction in which the spring 240 contracts is considered the positive direction. In other words, the inclination direction of the injection holes 222 and 232 for the first coil ends relative to the radial direction is the negative direction in the central axis direction, when the direction in which the inner cylinder 230 moves in the central axis direction against the biasing force of the spring 240 is considered the positive direction.

[0061] As shown in Figure 5A, when the inner cylinder 230 is positioned in the second relative position, the second coil end injection hole 224 of the outer cylinder 220 overlaps with the second coil end injection hole 234 of the inner cylinder 230, thereby communicating radially. As a result, the nozzle 210 can inject oil into the second coil end 170b through the second coil end injection holes 224 and 234, as indicated by the white arrows in Figure 4.

[0062] Here, as shown in Figure 3A, the area where the outer opening 234b of the second coil end injection hole 234 and the inner opening 224a of the second coil end injection hole 224 overlap when the inner cylinder 230 is positioned in the first relative position is defined as the third area. Also, as shown in Figure 5A, the area where the outer opening 234b of the second coil end injection hole 234 and the inner opening 224a of the second coil end injection hole 224 overlap when the inner cylinder 230 is positioned in the second relative position is defined as the fourth area.

[0063] Here, the third area is smaller than the fourth area. The smaller the overlapping area of ​​the injection holes 224 and 234 for the second coil end, the greater the oil flow velocity, making it easier to supply oil to the target location to be cooled.

[0064] Furthermore, the fourth area is larger than the third area. Therefore, the amount of oil injected into the second coil end 170b can be increased when the inner cylinder 230 is positioned in the second relative position compared to when it is positioned in the first relative position. In other words, by increasing the amount of oil injected into the second coil end 170b, the amount of cooling provided to the second coil end 170b can be increased.

[0065] As shown in Figure 5B, when the inner cylinder 230 is positioned in the second relative position, the core injection hole 226 of the outer cylinder 220 overlaps radially with and communicates with the core injection hole 236 of the inner cylinder 230. Therefore, as shown in Figure 4, the nozzle 210 can inject oil into the core 160 through the core injection holes 226 and 236. In other words, the nozzle 210 can start injecting oil into the core 160 from the state shown in Figure 2, where the injection of oil into the core 160 is stopped, as shown in Figure 4.

[0066] As shown in Figure 5C, when the inner cylinder 230 is positioned at the second relative position, the first coil end injection hole 222 of the outer cylinder 220 overlaps with the first coil end injection hole 232 of the inner cylinder 230, thereby communicating with it in a direction inclined in a predetermined direction with respect to the radial direction.

[0067] Here, as shown in Figure 3C, the area where the outer opening 232b of the first coil end injection hole 232 and the inner opening 222a of the first coil end injection hole 222 overlap when the inner cylinder 230 is positioned in the first relative position is defined as the first area. Also, as shown in Figure 5C, the area where the outer opening 232b of the first coil end injection hole 232 and the inner opening 222a of the first coil end injection hole 222 overlap when the inner cylinder 230 is positioned in the second relative position is defined as the second area.

[0068] Here, the first area is smaller than the second area. The smaller the overlapping area of ​​the injection holes 222 and 232 for the first coil end, the greater the oil flow velocity, making it easier to supply oil to the target location to be cooled.

[0069] Furthermore, the second area is larger than the first area. Therefore, when the inner cylinder 230 is positioned at the second relative position, the amount of oil injected into the first coil end 170a can be increased compared to when the inner cylinder 230 is positioned at the first relative position. In other words, by increasing the amount of oil injected into the first coil end 170a, the amount of cooling provided to the first coil end 170a can be increased.

[0070] Furthermore, when the inner cylinder 230 is positioned at the second relative position, the position of the outer opening 232b of the first coil end injection hole 232 and the position of the inner opening 222a of the first coil end injection hole 222 roughly coincide in the direction of the central axis. Also, the central axis of the first coil end injection hole 232 and the central axis of the first coil end injection hole 222 roughly coincide.

[0071] At this time, as shown in Figure 5C, the inner circumferential surface of the first coil end injection hole 232 and the inner circumferential surface of the first coil end injection hole 222 form a continuous inclined surface 260 from the inner circumferential surface of the inner cylinder 230 to the outer circumferential surface of the outer cylinder 220. The oil supplied to the inside of the inner cylinder 230 flows along the inclined surface 260 and is injected toward the stator 150. At this time, a predetermined direction inclined from the radial direction in which the oil flows through the first coil end injection holes 222 and 232 is defined as the communication direction of the first coil end injection holes 222 and 232.

[0072] At the second relative position, the boundary between the core 160 and the first coil end 170a lies on the extension of the central axis of the injection holes 222 and 232 for the first coil end. Therefore, the injection holes 222 and 232 for the first coil end can inject oil toward the boundary between the core 160 and the first coil end 170a, as shown by the white arrows in Figure 4. This allows for simultaneous cooling of the core 160 and the first coil end 170a.

[0073] As shown in Figures 2 and 4, by changing the relative position of the inner cylinder 230, the communication direction of the injection holes 222 and 232 for the first coil end can be changed. As a result, as can be seen by comparing Figures 2 and 4, the direction of oil injection can be changed. By changing the direction of oil injection, the target of cooling can be changed from the first coil end 170a to the core 160 and the first coil end 170a. In this embodiment, the target of cooling is changed from the first coil end 170a to the core 160 and the first coil end 170a, but it is not limited to this, and the target of cooling may be changed from the first coil end 170a to the core 160. In other words, by changing the communication direction of the injection holes 222 and 232 for the first coil end, it is sufficient that oil is injected at least toward the core 160.

[0074] As described above, the ECU 118 controls the EOP 250 so that the oil volume and oil pressure increase as the rotational speed of the motor 110 increases. At high rotational speeds of the motor 110, the heat generated by the core 160 of the stator 150 exceeds a threshold, in addition to the heat generated by the coil 170. Therefore, at high rotational speeds of the motor 110, the core 160, in addition to the coil 170, also needs to be cooled by oil.

[0075] The ECU 118 controls the EOP 250 so that the oil pressure becomes a second pressure, which is above a predetermined pressure, when the motor 110 is rotating at high speed. When the oil pressure becomes a second pressure, which is above the predetermined pressure, the first coil end injection holes 222 and 232 of the nozzle 210 inject oil toward the core 160 in addition to the first coil end 170a, as explained in Figures 4 and 5A to 5C. The second coil end injection holes 224 and 234 of the nozzle 210 also inject oil toward the second coil end 170b. The core injection holes 226 and 236 of the nozzle 210 also inject oil toward the core 160.

[0076] This allows oil to be injected into the core 160, first coil end 170a, and second coil end 170b, which require cooling when the motor 110 is rotating at high speed and the heat generated exceeds a threshold, thereby cooling them.

[0077] As described above, in the cooling device 200 of this embodiment, the relative position of the inner cylinder 230 with respect to the outer cylinder 220 changes due to the change in the pressure of the oil introduced into the inner cylinder 230. This change in relative position changes the overlapping area and communication direction of the first coil end injection holes 222 and 232, and the injection direction of the oil injected through the first coil end injection holes 222 and 232 becomes variable. Therefore, the core 160 and the first coil end 170a of the stator 150 can be switched and cooled using a single first coil end injection hole 222 or 232, eliminating the need to form a separate new injection hole. Furthermore, when switching between cooling the core 160 and the first coil end 170a, it is unnecessary to form a separate new injection hole near the first coil end injection holes 222 and 232, thus eliminating constraints on the arrangement of the injection holes. As a result, it is possible to achieve low cost and increased freedom in the arrangement of injection holes.

[0078] Embodiments of the present invention have been described above with reference to the attached drawings, but it goes without saying that the present invention is not limited to these embodiments. It is clear to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and these will naturally also fall within the technical scope of the present invention.

[0079] In the above embodiment, an example was described in which second coil end injection holes 224 and 234 are provided separately from the first coil end injection holes 222 and 232. However, the second coil end injection holes 224 and 234 are not an essential component, and they may not be provided.

[0080] In the above embodiment, an example was described in which core injection holes 226 and 236 are provided separately from the first coil end injection holes 222 and 232. However, the core injection holes 226 and 236 are not an essential component, and they may not be provided. [Explanation of Symbols]

[0081] 100 vehicles 110 Motor 150 stator 160 cores (second cooling target) 170 coils 170a First coil end (first object to be cooled) 170b Second coil end (third object to be cooled) 200 Cooling device 210 nozzles 220 Outer cylinder 222 Injection holes for the first coil end 224 Injection holes for the second coil end 226 injection holes for core 230 Inner cylinder 232 Injection holes for the first coil end 234 Injection holes for the second coil end 236 injection holes for core 240 Springs (elastic components) 250 EOP

Claims

1. A cooling device for cooling an object to be cooled, A pump that supplies coolant, A nozzle positioned opposite the object to be cooled, which sprays the coolant supplied from the pump toward the object to be cooled, Equipped with, The aforementioned nozzle is Outer cylinder and An inner cylinder is provided inside the outer cylinder so as to be slidable in the axial direction of the outer cylinder, and into which the cooling liquid is introduced. An elastic member connected between the outer cylinder and the inner cylinder, which biases the inner cylinder in the axial direction, The outer cylinder has a first inclined injection hole formed through it, which is inclined in a predetermined direction with respect to the radial direction of the outer cylinder, In the inner cylinder, a second inclined injection hole is formed through the cylinder, inclined in a predetermined direction with respect to the radial direction, Equipped with, The inner cylinder slides relative to the outer cylinder in the axial direction against the biasing force of the elastic member due to the pressure of the coolant introduced into the inner cylinder, A cooling device configured such that the relative position of the inner cylinder with respect to the outer cylinder changes due to a change in the pressure of the coolant introduced into the inner cylinder, and the area in which the first inclined injection hole and the second inclined injection hole overlap and the direction in which the first inclined injection hole and the second inclined injection hole communicate change, thereby making the injection direction of the coolant injected through the first inclined injection hole and the second inclined injection hole variable.

2. When the direction in which the inner cylinder moves axially against the biasing force of the elastic member due to the increase in pressure of the coolant introduced into the inner cylinder is defined as the positive axial direction, The predetermined direction is the negative direction opposite to the positive direction in the axial direction. The cooling device according to claim 1.

3. The object to be cooled is, The first inclined injection hole of the outer cylinder and the first object to be cooled are arranged facing each other in the radial direction, The first inclined injection hole of the outer cylinder and the second object to be cooled are arranged opposite each other in a direction inclined in the predetermined direction with respect to the radial direction, Includes, When the pressure of the coolant is a first pressure, the inner cylinder is positioned at a first relative position with respect to the outer cylinder, the direction in which the first inclined injection hole and the second inclined injection hole communicate is the radial direction, and the coolant is injected from the first inclined injection hole and the second inclined injection hole toward the first object to be cooled. When the pressure of the coolant is greater than the first pressure, the inner cylinder is positioned at a second relative position on the positive axial side of the first relative position, the direction in which the first inclined injection hole and the second inclined injection hole communicate is inclined in the predetermined direction with respect to the radial direction, and the coolant is injected from the first inclined injection hole and the second inclined injection hole toward at least the second object to be cooled. The cooling device according to claim 2.

4. The outer cylinder is provided with a third injection hole located at a position facing the second object to be cooled in the radial direction, and which is formed to penetrate in the radial direction, A fourth injection hole is provided in the inner cylinder at a position facing the second object to be cooled in the radial direction, and is formed to penetrate in the radial direction, Equipped with, When the inner cylinder is in the first relative position, the third injection hole and the fourth injection hole are not in communication. When the inner cylinder is in the second relative position, the third injection port and the fourth injection port are in communication. The cooling device according to claim 3.

5. The outer cylinder is provided with a fifth injection hole located at a position facing the third object to be cooled in the radial direction, and which is formed to penetrate in the radial direction, A sixth injection hole is provided in the inner cylinder at a position facing the third object to be cooled in the radial direction, and is formed to penetrate in the radial direction, Equipped with, The area where the fifth injection hole and the sixth injection hole overlap when the inner cylinder is in the second relative position is greater than the area where the fifth injection hole and the sixth injection hole overlap when the inner cylinder is in the first relative position. The cooling device according to claim 3 or 4.

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