Cooling system

Abstract

To provide a cooling system having an air vent valve.SOLUTION: A cooling system includes a cooling flow passage in which a coolant flows and an air vent valve disposed on the cooling flow passage. The air vent valve includes: a housing having an exhaust passage for communicating the cooling flow passage with outside; a valve element accommodated in the housing, movable between an upper limit position for closing the exhaust passage and a lower limit position for opening the exhaust passage and energized toward the upper limit position by using pressure in the cooling flow passage; an elastic member that energizes the valve element toward the lower limit position and allows the valve element to move to the upper limit position when the pressure in the cooling flow passage is larger than a predetermined value; and a plug body disposed at a predetermined closing position relative to the housing. The plug element closes the exhaust passage and abuts on the valve element to move the valve element to the lower limit position when moved to the closing position, and opens the exhaust passage before the valve element reaches the upper limit position when moved from the closing position.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a cooling system, and more particularly to a cooling system having an air bleed valve. [Background technology]

[0002] Patent Document 1 describes an air bleed valve. This air bleed valve includes a valve biased by a spring. The valve moves in response to the magnitude of the biasing force of the spring and the pressure of the hydraulic fluid, thereby opening and closing the air bleed valve. This type of air bleed valve can also be used in cooling systems. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-077893 Summary of the Invention [Problem to be solved by the invention]

[0004] In the air bleed valves described above, the biasing force of the spring must be accurately adjusted according to the expected pressure of the hydraulic fluid. If the biasing force of the spring is not set correctly, for example, if the biasing force of the spring is too high, the air bleed valve will not open and air will not be able to be discharged. On the other hand, if the biasing force of the spring is too low, the air bleed valve will close before sufficient air has been discharged. This poses a problem of difficulty in designing the air bleed valve, including setting the biasing force of the spring, and limited design freedom. [Means for solving the problem]

[0005] To solve the above-mentioned problems, this specification provides a cooling system. The cooling system includes a cooling flow path through which a coolant flows and an air vent valve disposed in the cooling flow path. The air vent valve includes a housing having an exhaust path that connects the cooling flow path to the outside, a valve element housed in the housing, movable between an upper limit position that closes the exhaust path and a lower limit position that opens the exhaust path, and is biased toward the upper limit position by pressure within the cooling flow path, an elastic member that biases the valve element toward the lower limit position and allows the valve element to move to the upper limit position when the pressure within the cooling flow path is greater than a predetermined value, and a plug element disposed at a predetermined closing position relative to the housing. In this cooling system, the plug element closes the exhaust path when moved to the closing position and abuts against the valve element to move the valve element to the lower limit position, and when moved from the closing position, opens the exhaust path before the valve element reaches the upper limit position.

[0006] With the above-described configuration, the cooling flow path can be filled with coolant with the plug moved from the closed position. If air is present in the cooling flow path while the coolant is being filled, the pressure in the cooling flow path is relatively low, and the valve body is maintained in the lower limit position. This opens the exhaust path and allows air to be discharged from the cooling flow path. As the air is discharged and the pressure in the cooling flow path increases, the valve body moves to the upper limit position. This closes the exhaust path and stops the discharge of air (and coolant). The plug is then placed in the closed position, so that the exhaust path is closed by the plug. At this time, the valve body abuts against the plug and is constrained in the lower limit position.

[0007] If the biasing force of the elastic member is set too high relative to the pressure inside the cooling flow path, the valve body will not close the exhaust path even after the air has been exhausted, resulting in unnecessary exhaust of coolant. Even in such cases, by placing the plug in the closed position, the exhaust path will be closed by the plug body, preventing the exhaust of coolant. On the other hand, if the biasing force of the elastic member is set too low, the valve body will close the exhaust path before the air has been exhausted. In such cases, it is advisable to temporarily move the plug from the closed position after placing it in the closed position. This will open the exhaust path and allow the air to be exhausted.

[0008] In addition, when the plug is in the closed position, the valve element is restrained in the lower limit position by contact with the plug, so that even if vibration is transmitted to the air vent valve, the valve element does not vibrate relative to the housing, preventing, for example, the generation of abnormal noise. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram illustrating a cooling system. [Figure 2] FIG. 2 is a schematic cross-sectional view of an air bleed valve of the cooling system according to the first embodiment. [Figure 3] 5A to 5C are diagrams illustrating the movement of the air vent valve of the first embodiment of the cooling system when air is discharged. [Figure 4] FIG. 10 is a schematic cross-sectional view of an air bleed valve of a second embodiment of a cooling system. [Figure 5] 10A and 10B are diagrams illustrating the movement of the air vent valve of the second embodiment of the cooling system when air is discharged. DETAILED DESCRIPTION OF THE INVENTION

[0010] (First embodiment) A cooling system 1 according to a first embodiment will be described with reference to the drawings. The cooling system 1 is mounted on, for example, a vehicle to cool components mounted on the vehicle. The vehicle referred to here is not particularly limited and may be, for example, a battery electric vehicle (BEV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), a fuel cell electric vehicle (FCEV), or an engine vehicle.

[0011] As shown in FIG. 1 , the cooling system 1 includes a cooling flow path 105 and an air vent valve 100. The cooling flow path 105 is a path through which a coolant flows. The cooling flow path 105 is configured using a tubular member such as a pipe or a tube. The tubular member may be configured from, for example, metal, rubber, or plastic, but is not limited to, a material. The coolant may be, for example, cooling water, or alternatively, other liquids used for heat exchange, such as oil. The air vent valve 100 is disposed on the cooling flow path 105. The air vent valve 100 discharges air present in the cooling flow path 105 to the outside. Specifically, in an outlet section 106 of the cooling flow path 105, a portion of the coolant and air flowing through the cooling flow path 105 is diverted to the air vent valve 100.

[0012] As shown in FIG. 1, the cooling system 1 may further include a heat exchanger 101, a reservoir tank 102, a radiator 103, and a pump 104. These components are provided on a cooling flow path 105, and the coolant circulates through the cooling flow path 105. The heat exchanger 101 is disposed on an object to be cooled (not shown). The object to be cooled is, for example, a power conversion unit, and has heat-generating elements such as inverter switching elements. Additionally or alternatively, the object to be cooled may be a drive motor or a battery. In the heat exchanger 101, heat exchange occurs between the object to be cooled and the coolant. This heat exchange cools the object to be cooled and heats the coolant.

[0013] The reservoir tank 102 has a space for storing the coolant and can act as a buffer to reduce the effects of the coolant expanding when heated. The reservoir tank 102 is made of a material such as metal or plastic. The reservoir tank 102 may have an inlet (not shown) for injecting the coolant. In this embodiment, the heat exchanger 101 is disposed at a position higher than the liquid level of the coolant in the reservoir tank 102. The radiator 103 is a radiator that dissipates heat from the coolant. Any known radiator can be used as the radiator 103. The coolant heated by the heat exchanger 101 is cooled by passing through the radiator 103. The pump 104 circulates the coolant in the cooling flow path 105 by pumping the coolant. Any known pump can be used as the pump 104. The pump 104 may be, for example, an electric pump. However, in another embodiment, the pump 104 may be a type that is connected to the crankshaft of the engine (ICE) and operates by receiving rotational power from the engine.

[0014] As shown in Fig. 2, the air vent valve 100 includes a housing 210, a valve body 230, an elastic member 240, and a plug body 250. The housing 210 is disposed so as to surround the outlet 107 of the outlet section 106 of the cooling flow path 105. The housing 210 is made of a material such as metal or plastic. As shown in Fig. 2, the housing 210 includes an exhaust path 220. The exhaust path 220 is provided within the housing 210 and connects the cooling flow path 105 to the outside.

[0015] The valve element 230 is accommodated in the housing 210. The valve element 230 is made of a material such as metal or plastic. The valve element 230 is movable between an upper limit position shown in FIG. 3(C) and a lower limit position shown in FIG. 3(B). When the valve element 230 is located at the upper limit position, the exhaust path 220 is closed. Specifically, the exhaust path 220 is closed when the tip 231 of the valve element 230 abuts against the first opening 223 of the exhaust path 220. When the valve element 230 is located at the lower limit position, the exhaust path 220 is opened. Specifically, the tip 231 of the valve element 230 moves away from the first opening 223 of the exhaust path 220, thereby opening the exhaust path 220. At this time, the base end 232 of the valve element 230 abuts against the cooling channel 105 (or the housing 210). The valve element 230 is urged toward the upper limit position by the pressure within the cooling channel 105.

[0016] The elastic member 240 is accommodated in the housing 210. The valve element 230 is biased toward the lower limit position by the elastic member 240. As an example, the elastic member 240 in this embodiment is a coil spring, and is arranged coaxially with the valve element 230. The elastic member 240 has a spring load designed to allow the valve element 230 to move to the upper limit position when the pressure in the cooling flow path 105 is greater than a predetermined value. Note that the elastic member 240 is not limited to a coil spring, and may be another type of spring member. In this case, the specific configuration (type, size, material) of the spring member is not particularly limited. In another embodiment, the elastic member 240 may be composed of multiple members.

[0017] The plug 250 is attached to the housing 210 and is configured to be movable to a closed position shown in FIG. 3(A). As shown in FIG. 3(A), the plug 250 has a support portion 251 and a plug portion 252. The bottom surface of the plug portion 252 of the plug 250 is flat. Meanwhile, the tip 231 of the valve body 230 is conical. Therefore, when the plug 250 moves from the closed position, the plug 250 opens the exhaust path 220 before the valve body 230 reaches the upper limit position. In another embodiment, the plug portion 252 may be conical, and the upper surface of the tip 231 may be flat. At least one of the plug portion 252 of the plug 250 and the tip 231 of the valve body 230 may have a shape that protrudes toward the other.

[0018] To fix the plug 250, a fixing mechanism such as a screw or a locking pin is used. When the plug 250 is in the closed position, the exhaust passage 220 is closed by the plug 250, regardless of the valve body 230. More specifically, the bottom surface of the plug portion 252 of the plug 250 closes the first opening 223 of the exhaust passage 220, and the side surface of the plug portion 252 closes the second opening 224 of the exhaust passage 220. At this time, the valve body 230 abuts against the plug 250 and is restrained in the lower limit position. Therefore, even if vibration is transmitted to the air vent valve 100, the valve body 230 will not vibrate relative to the housing 210, preventing, for example, the generation of abnormal noise.

[0019] The following describes how to operate the air vent valve 100. As shown in Fig. 3(A), before air starts to be discharged, the plug 250 is attached to the closed position and the exhaust path 220 is closed. As shown in Fig. 3(B), when air starts to be discharged, the plug 250 is moved from the closed position and the exhaust path 220 is opened. As air is discharged, the pressure inside the cooling channel 105 increases.

[0020] If the biasing force of the elastic member 240 is set correctly, the valve element 230 moves to the upper limit position when all the air is discharged, as shown in Figure 3(C). This stops the discharge of air and prevents unnecessary discharge of coolant. After that, by placing the plug element 250 in the closed position, the valve element 230 is restrained in the lower limit position, preventing the generation of abnormal noise, etc.

[0021] If the biasing force of the elastic member 240 is set too high, the valve body 230 cannot reach the upper limit position and the exhaust path 220 is not blocked even after the air has been exhausted. In this case, the coolant will be unnecessarily discharged. However, as shown in FIG. 3(A), by placing the plug body 250 in the blocking position, the exhaust path 220 can be blocked. Therefore, the situation in which the coolant is unnecessarily discharged can be avoided.

[0022] If the biasing force of the elastic member 240 is set too low, the valve element 230 will move to the upper limit position and close the exhaust path 220 before the air is completely discharged. In this case, the coolant will not be discharged unnecessarily, but air will remain in the cooling flow path 105. However, after placing the plug 250 in the closed position, moving the plug 250 slightly from the closed position, as shown in FIG. 3(D), opens the exhaust path 220 and allows the remaining air to be discharged. Furthermore, if the biasing force of the elastic member 240 is set too low, the coolant will not be discharged, making it difficult to determine whether air remains. Even in such cases, the air in the cooling flow path 105 can be reliably discharged by slightly moving the plug 250 from the closed position and confirming that the coolant has been discharged. (Second embodiment)

[0023] The second embodiment of the cooling system 1 has a structure that is partially common to the first embodiment of the cooling system 1. A description of the common structure will be omitted.

[0024] 4, the cooling system 1 includes an air bleed valve 400 instead of the air bleed valve 100. In the outflow section 106 of the cooling flow path 105, a portion of the coolant and air flowing in the cooling flow path 105 is diverted to the air bleed valve 400 through the outlet port 108. The air bleed valve 400 includes a support portion 410, an intake side check ball 411, a discharge side check ball 412, an intake port 413, an exhaust port 414, an intake side spring 421, a main spring 422, a discharge side spring 423, a piston 430 having an intake side piston 431 and a discharge side piston 432, a magnetic circuit configuration portion 440, a pusher 441, a plunger 442, and a winding 443.

[0025] An suction side chamber is formed between suction side check ball 411 and discharge side check ball 412 and suction side piston 431. An discharge side chamber is formed between discharge side check ball 412 and suction side piston 431 and discharge side piston 432. Although not limited to, suction side spring 421, main spring 422, and discharge side spring 423 are coil springs in this embodiment. Suction side check ball 411 is biased by suction side spring 421 to a position where it is almost fixed relative to support portion 410. Discharge side check ball 412 is biased by discharge side spring 423 to a position where it is almost fixed relative to suction side piston 431.

[0026] Piston 430, pusher 441, and plunger 44 are arranged coaxially and are each movable between an advanced position closest to suction side check ball 411 and a retracted position farthest from suction side check ball 411. Main spring 422 biases suction side piston 431 axially toward pusher 441. Therefore, piston 430, pusher 441, and plunger 442 abut against each other in sequence. Magnetic circuit configuration unit 440 may be a linear SOL type magnetic circuit or an ON / OFF SOL type magnetic circuit.

[0027] 5(A), when the power supply (not shown) that supplies power to the magnetic circuit configuration 440 is turned off, the plunger 442 moves to the retracted position. As the plunger 442 moves back, the piston 430 and the pusher 441 move back due to the main spring 422, and the suction chamber expands. This creates negative pressure in the suction chamber, and air from the cooling passage 105 is sucked into the suction chamber through the suction check ball 411.

[0028] 5(B), when a power supply (not shown) that supplies power to magnetic circuit configuration unit 440 is ON, plunger 442 moves to the forward position. Pusher 441 moves as plunger 442 moves forward, causing piston 430 to move forward and the suction chamber to contract. This generates positive pressure in the suction chamber, and the absorbed air is discharged to the outside through exhaust port 414.

[0029] According to this embodiment, exhaust can be started and stopped by controlling the power supply, which eliminates the need to consider the setting of the valve opening pressure. (Other embodiments)

[0030] In another embodiment, the air bleed valve 100 may further include a tank for collecting coolant unintentionally discharged from the exhaust path 220. Alternatively, instead of the tank, a pipe may be provided for collecting the coolant discharged from the air bleed valve 100 into the reservoir tank 102. Similarly, a tank or a pipe may be provided for the exhaust port 414 of the air bleed valve 400 so as to collect the coolant discharged from the exhaust port 414.

[0031] In other embodiments, the air vent valve 100 and the air vent valve 400 may have a plug, seal or sealing structure that closes the exhaust port on the housing after the air has been vented.

[0032] In each of the above-described embodiments, the pump 104 may be a radial piston pump in which multiple piston pumps are arranged radially around the rotation shaft of the motor. In this case, some of the radial piston pumps may be used for the hydraulic circuit for the brake, and the other part may be used as the pump 104 for the cooling system 1. [Explanation of symbols]

[0033] 1: Cooling system, 100: Air vent valve, 105: Cooling flow path, 210: Housing, 220: Exhaust path, 230: Valve body, 240: Elastic member, 250: Plug body,

Claims

[Claim 1] 1. A cooling system comprising: a cooling flow path through which a coolant flows; an air vent valve disposed on the cooling flow path; It is equipped with The air vent valve is a housing having an exhaust path that connects the cooling flow path to the outside; a valve element accommodated in the housing, movable between an upper limit position at which the exhaust passage is closed and a lower limit position at which the exhaust passage is opened, and biased toward the upper limit position by pressure within the cooling passage; an elastic member that biases the valve element toward the lower limit position and allows the valve element to move to the upper limit position when the pressure in the cooling flow path is greater than a predetermined value; a plug that is disposed in a predetermined closing position relative to the housing, The plug is When the valve is moved to the closing position, the exhaust passage is closed and the valve body is brought into contact with the valve and moved to the lower limit position. When the valve element moves from the closed position, the exhaust passage is opened before the valve element reaches the upper limit position. Cooling system.

Images