Coolant pipe for in-vehicle device

Abstract

To facilitate inspection of a liquid amount of cooling liquid in cooling liquid piping through which the cooling liquid for cooling a battery or the like of a vehicle flows.SOLUTION: The coolant pipe 22 connects the battery 16 and the inverter 18, which are to be cooled, to the radiator 20, which dissipates heat, so that the coolant circulates. The coolant pipe 22 is provided with a reserve tank 26 for storing a spare coolant. An air bubble visual confirmation structure 32 for confirming air bubbles inside the cooling liquid piping is provided at a position different from the reserve tank 26 and visible when the hood 30 is opened. The air bubble visual recognition structure 32 has a transparent part, and air bubbles mixed in the cooling liquid are confirmed from the transparent part to inspect the liquid amount of the cooling liquid.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a coolant pipe that connects an on-board device mounted on a vehicle to a radiator so that a coolant circulates therebetween. [Background technology]

[0002] Vehicles are equipped with devices that require cooling or temperature control. Such on-board devices include an engine and electric motor that drive the vehicle, a battery that supplies power to the electric motor, and an inverter or converter that performs AC / DC power conversion and voltage conversion between the electric motor and the battery. When these on-board devices are cooled using a coolant, a radiator is used to dissipate the heat of the coolant. The coolant circulates through coolant piping that connects the on-board devices to be cooled to the radiator. Patent Document 1 listed below shows a level gauge that has a transparent pipe that is connected to the inside of a fuel tank and is located outside the tank. The fuel level in the tank can be confirmed by checking the position of the liquid level in the transparent pipe. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-61219 Summary of the Invention [Problem to be solved by the invention]

[0004] The coolant level is usually checked by checking the level in the reserve tank, which stores extra coolant. However, if the reserve tank is located in a place that is difficult to see, it is necessary to check the coolant level using other methods.

[0005] An object of the present invention is to provide a coolant piping system that allows inspection of the coolant level in a reserve tank, where it is difficult to inspect the level of the coolant. [Means for solving the problem]

[0006] The coolant piping of the present invention is a coolant piping that connects the on-board equipment to be cooled to a radiator that dissipates heat generated by the on-board equipment through the coolant so that the coolant circulates, and is located in a position separate from the reserve tank that stores spare coolant and is visible, and has a transparent part that allows air bubbles inside the coolant piping to be checked. [Effects of the Invention]

[0007] The coolant level can be checked in areas other than the reserve tank. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a side view schematically showing a front part of a vehicle equipped with a coolant pipe according to an embodiment; [Figure 2] 10A and 10B are diagrams showing an example of a bubble visualizing structure for checking bubbles mixed in the coolant. [Figure 3] 10A and 10B are diagrams showing another example of a bubble visualizing structure for checking bubbles mixed in the coolant. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, unless otherwise specified, terms indicating relative positions and directions such as front, rear, left, right, up, down, etc., indicate relative positions and directions with respect to the vehicle. In each drawing, the arrow FR points forward, the arrow UP points upward, the arrow LH points leftward, and the arrow OUT points outward in the vehicle width direction.

[0010] FIG. 1 is a diagram showing a schematic internal structure of the front of a vehicle 10. The vehicle 10 is a so-called electric vehicle equipped only with an electric motor as a prime mover for driving the vehicle 10. The front of the vehicle 10 is equipped with an electric motor 14 that rotates front wheels 12, a battery 16 that stores power supplied to the electric motor 14, and an inverter 18 that converts DC power from the battery 16 to AC power and supplies the AC power to the electric motor 14. The electric motor 14 may be integrated with a reducer that reduces the output of the electric motor 14. The inverter 18 also converts AC power generated by the electric motor 14 driven by the inertia of the vehicle into DC power and charges the battery 16. The vehicle may also be equipped with a DC-DC converter (not shown) that reduces the voltage of the battery 16 to supply the power to on-board electrical equipment such as lighting and electronic control units (ECUs) that control various devices. The DC-DC converter may be integrated with the inverter 18. A portion or the front of the battery 16 may be mounted under the floor of the vehicle 10 .

[0011] The vehicle 10 is equipped with a cooling system for managing the temperatures of the battery 16 and the inverter 18. The cooling system includes a radiator 20 and coolant piping 22 that forms a circulation flow path connecting the radiator 20 with on-board equipment to be cooled. The on-board equipment to be cooled may be the battery 16 and the inverter 18. In the vehicle 10, the coolant piping 22 forms a circulation flow path by sequentially connecting the battery 16, the inverter 18, and the radiator 20. The coolant piping 22 is provided with a circulation pump 24 that circulates the coolant.

[0012] The cooling system further includes a reserve tank 26 that compensates for any excess or deficiency of the coolant in the coolant pipe 22. The reserve tank 26 may be provided in the coolant pipe 22, and the coolant flowing through the coolant pipe 22 passes through the reserve tank 26 and circulates through the coolant pipe 22. When the coolant in the coolant pipe 22 heats and expands, the amount of coolant in the reserve tank 26 increases, and the expanded amount is stored in the reserve tank 26. When the coolant in the coolant pipe 22 cools and contracts, the deficiency is replenished from within the reserve tank 26. Air in the coolant pipe 22 remains in the upper part of the reserve tank 26, and the coolant is sent from the lower part of the reserve tank 26 toward the circulation pump. Therefore, the height of the coolant level in the reserve tank 26 corresponds to the amount of coolant in the coolant pipe 22. A typical coolant reservoir tank is made of a translucent material, allowing the coolant inside to be seen through and the liquid level to be visually checked from the outside.

[0013] The coolant is sent from the circulation pump 24 to the radiator 20, where it dissipates heat, and then from the radiator 20 to the inverter 18. The coolant cools electronic elements such as power transistors within the inverter 18. The coolant then flows from the inverter 18 to the battery 16, where it cools the cells within the battery 16. The coolant flow paths within the inverter 18 and the battery 16 are actually complex, but are shown simplified in FIG. 1. The coolant then returns to the circulation pump 24 from the battery 16 via the reserve tank 26.

[0014] In the vehicle 10, due to layout requirements, the reserve tank 26 is located below the fixed cowl 28, which is part of the vehicle body. An openable hood 30 is located in front of the cowl 28. Because the reserve tank 26 is located behind the opening in the vehicle body that is created when the hood 30 is opened, it is difficult to check the liquid level in the reserve tank 26. In the vehicle 10, the coolant level can be checked at a position separate from the reserve tank 26.

[0015] The amount of cooling water in the coolant pipe 22 can be checked by checking whether air bubbles are mixed in the flowing coolant. When the amount of cooling water is insufficient, air bubbles will be mixed in the coolant flowing through the coolant pipe 22. The coolant pipe 22 is provided with an air bubble viewing structure 32 that allows the coolant flowing inside to be visually confirmed. The air bubble viewing structure 32 has a transparent portion that allows the air bubbles in the coolant flowing inside to be confirmed. The presence or absence of air bubbles mixed in the coolant can be confirmed through the air bubble viewing structure 32, making it possible to determine whether the amount of cooling water is insufficient.

[0016] 2 is a diagram showing a specific example of a bubble visualization structure 32. The upper diagram is a plan view, and the lower diagram is a side view. The bubble visualization structure 32 has an L-shaped pipe 34 bent into an L shape and a window 36 provided on the top surface of the L-shaped pipe 34. Glass or transparent resin is placed in the window 36, and the coolant flowing inside the pipe can be seen through the window 36. If air bubbles are mixed in the flowing coolant, it can be seen that there is a shortage of coolant.

[0017] Alternatively, a protrusion may be provided on the top surface of the L-shaped tube 34 so that air bubbles can accumulate there. The trapped air bubbles can be visually confirmed through a window 36 to determine whether air bubbles have been mixed in. A cap may be provided on the protrusion, and the cap may be opened to allow the air bubbles to be discharged. In this case, the cap may be provided with a window 36 for visually checking for air bubbles.

[0018] 3 is a diagram showing another example of a bubble viewing structure. The bubble viewing structure 38 is used in place of the above-described bubble viewing structure 32. The bubble viewing structure 38 is composed of a tube that is transparent enough to allow the interior to be seen through, in this example, an L-shaped tube 40 that is bent into an L shape. The coolant flowing inside the tube can be seen through the L-shaped tube 40. If air bubbles are mixed in the flowing coolant, it is clear that there is a shortage of coolant.

[0019] 1 is part of the flow path through which the coolant circulates, but it may also be provided in a flow path branching off from the circulating flow path. Specifically, the reserve tank may be provided at the end of a branch pipe branching off from the coolant pipe 22 between the battery 16 and the circulation pump 24. Excess coolant in the coolant pipe 22 is sent to the reserve tank through the branch pipe, and when the coolant pipe 22 runs short of coolant, the coolant is replenished from the reserve tank via the branch pipe.

[0020] The coolant may be used to heat the battery 16. In this case, the cooling system includes a heater that heats the coolant, which then heats the battery 16.

[0021] The vehicle 10 is an electric vehicle equipped only with an electric motor as a prime mover for driving the vehicle, but the above-described coolant piping can also be applied to vehicles equipped only with an internal combustion engine as a prime mover, or to vehicles equipped with an internal combustion engine and an electric motor. In a vehicle equipped with an internal combustion engine, the internal combustion engine is also an on-board device to be cooled. [Explanation of symbols]

[0022] 10 vehicle, 14 electric motor, 16 battery, 18 inverter, 20 radiator, 22 coolant piping, 24 circulation pump, 26 reserve tank, 32, 38 bubble viewing structure, 34, 40 L-shaped pipe, 36 window.

Claims

[Claim 1] A coolant pipe that connects an on-board device to be cooled to a radiator that dissipates heat generated by the on-board device through the coolant so that the coolant circulates, the coolant pipe having a transparent portion in a visible position and separate from a reserve tank that stores spare coolant, allowing air bubbles inside the coolant pipe to be confirmed.

Images