JP3700745B2 - Engine cooling system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cooling device for an engine mounted on a vehicle such as an automobile.
[0002]
[Prior art]
The cooling of an engine mounted on a vehicle is generally a water cooling type using cooling water. This water cooling system is a cycle in which cooling water is guided to the water jacket of the engine to absorb heat, and the high-temperature cooling water is guided to the radiator to dissipate heat to the atmosphere with the wind from the front and the intake air from the cooling fan. Do. In the general structure of a radiator, an upper tank and a lower tank are connected by a thin pipe, and wind is passed between fins attached to the outer periphery of the thin pipe.
[0003]
By the way, the cooling water filled in the cooling system passage increases in pressure due to expansion or the like when the engine is in a warm-up state, and decreases in pressure when the engine is in a cool-down state. Therefore, if the upper tank of the radiator is fully filled in the cold state, it will overflow when the engine is warmed up. In the past, the upper end of the tube was attached to the portion of the radiator upper tank where the cap for water injection was mounted, and the overflowing cooling water was discarded on the ground. However, in such a structure, even if the amount of cooling water is reduced, it is not replenished. Therefore, the amount of cooling water is periodically inspected and replenished as necessary. .
[0004]
Since it is very complicated to periodically check and replenish the amount of cooling water in this way, a reservoir tank is provided separately from the radiator, and the cooling water expands when the engine is warmed up. In such a case, the surplus is led to the reservoir tank and stored there, and when the cooling water contracts while the engine is in a cold state, the deficiency is drawn out from the reservoir tank to compensate.
[0005]
The reservoir tank provided for this purpose is located near the radiator in the engine room at almost the same height as the radiator, but depending on the model, the reservoir tank is located above the radiator for layout reasons. There is something to do. Examples of such a vehicle model include a truck of a small automobile in which an engine is placed under the floor and a radiator is disposed in the front part of the cabin (JP-A-8-74576, JP-A-8-226328, etc.). reference). In these publications, the reservoir tank cap also serves as a water inlet to the radiator.
[0006]
FIG. 5 shows a freight vehicle of the type targeted by the present invention. The lorry 1 has a structure in which a cabin 3 and a loading platform 4 are mounted on an upper portion of a chassis frame 2, and an engine 5 is defined at a rear lower portion of the cabin 3 by a dash panel 6 at a front portion of the cabin 3. A radiator 8 and a reservoir tank 9 are disposed in the front room 7 respectively. Reference numeral 10 denotes a front hood that covers the front portion of the front room 7.
[0007]
FIG. 6 is an enlarged view of the front room 7 in FIG. As shown in this figure, the reservoir tank 9 is disposed immediately above the radiator 8, is provided inside the reservoir tank 9, and has an upper end of a pipe 11 whose lower end is opened near the bottom of the reservoir tank 9, and the radiator 8. A portion adjacent to the water injection cap 13 provided in the upper tank 12 is communicated with a pipe 14.
[0008]
Reference numeral 15 denotes a lower tank of the radiator 8, and 16 denotes a water injection cap of the reservoir tank 9. A pipe 17 has one end connected to the upper tank 12 and a pipe 18 connected to the lower tank 15. The other end (not shown) communicates with the water jacket of the engine 5 (see FIG. 5). A water pump is connected to a part of the circulation path of these pipes 17 and 18, and cooling water is circulated by this water pump. In a normal state, there is a water level difference of H between the coolant level in the reservoir tank 9 and the water injection cap 13 of the radiator 8. 19 is a pot for water injection.
[0009]
FIG. 7 shows a general structure of the upper tank 12 and the water injection cap 13 of the radiator 8. The upper part of the upper tank 12 is opened in a cylindrical shape and is formed in a cap receiving part 12a, into which a water injection cap 13 is fitted. The description of the holding structure of the water injection cap 13 is omitted, but when it is attached to the upper tank 12, the inner plate 20 is pushed so as to contact the cap receiving portion 12a, and then coupled by rotating it by an appropriate angle.
[0010]
The water injection cap 13 is provided with a valve body 21, and the guide member 22 presses the outer periphery so as to move up and down. A seal member 23 is attached to the outer periphery of the lower surface of the valve body 21, and the pressurizing valve 24 is formed by being seated on the valve seat 12 b formed in the upper tank 12. Reference numeral 25 denotes a spring, which pushes the valve body 21 downward in the figure. The upper tank 12 is integrally formed with a pipe 12c that extends laterally, and a pressure valve 24 opens and closes the pipe 12c.
[0011]
A stepped hole 21 a is provided in the center of the valve body 21, and an annular seal member 26 is attached to the lower surface of the outer periphery. A dish-shaped valve element 27 is supported by a shaft 28 and pressed against the seal member 26. A plate 29 is attached to the upper end of the shaft 28, and the valve element 27 is pressed against the seal member 26 by a spring 30 interposed between the plate 29 and the stepped portion of the stepped hole 21 a, and the negative pressure valve 31 is formed.
[0012]
The water injection cap 13 having the above structure is shown in FIG. 7 in a normal state. When the engine is warmed up and the temperature of the cooling water rises, the pressure rises. As shown in FIG. 8, the pressure of the spring 25 is overcome and the valve body 21 is pushed up. The portion flows through the pipe 12c to the reservoir tank 9 (see FIG. 5) side and is accumulated.
[0013]
When the engine is stopped and time elapses and the engine is in a cold state, the inside of the upper tank 12 (inside the radiator 8) is in a negative pressure state. Therefore, as shown in FIG. Pulled downward against the force. As a result, the cooling water enters the upper tank 12 from the pipe 12 side (reservoir tank 9 side) as indicated by an arrow in FIG. In this way, the amount of cooling water in the radiator 8 is kept constant.
[0014]
[Problems to be solved by the invention]
As described above, the pressurization valve 24 of the water injection cap 13 is provided between the upper tank 12 of the radiator 8 and the pipe 12c. However, if the water injection cap 13 is removed for inspection work or the like, the communication state is established. Therefore, all the cooling water in the reservoir tank 9 provided at a higher position than the upper tank 12 is sucked out and flows out. The engine cooling water generally contains an antifreeze called coolant in the water, so if it flows out, it must be replenished, which is complicated.
[0015]
The present invention has been made in view of this point, and in an engine cooling apparatus having a structure in which a reservoir tank is disposed above a radiator, the cooling water flows out to the outside even if the cap for water injection of the upper tank is removed. An object of the present invention is to provide a cooling device for an engine that prevents this from happening.
[0016]
[Means for Solving the Problems]
According to the present invention, as means for solving the above-mentioned problems, in the invention described in claim 1, a reservoir tank is disposed above a radiator in which a cap for water injection is provided in the upper tank, and the interior of the reservoir tank is And a cooling tank for the engine in which the upper tank of the radiator is connected by a pipe, a blocking means for blocking a flow of the cooling water between the upper tank and the reservoir tank of the radiator in a part of the pipe or a portion of the reservoir tank. The blocking means is formed by an atmospheric opening provided in a part of the pipe or a reservoir tank .
[0017]
The invention described in claim 2 is characterized in that in the structure described in claim 1, the atmospheric opening provided in a part of the pipe or the reservoir tank is configured to be closed with a cap. To do.
[0018]
According to a third aspect of the present invention, there is provided an engine in which a reservoir tank is disposed above a radiator in which a water injection cap is provided in the upper tank, and the inside of the reservoir tank and the upper tank of the radiator are connected by a pipe. In the cooling apparatus, a part of the pipe or a part of the reservoir tank is provided with a blocking means for blocking a flow of the cooling water between the upper tank and the reservoir tank of the radiator, and the blocking means is connected to the overflow pipe of the reservoir tank. It is characterized in that it is formed by an atmospheric blocking part provided in the part.
[0019]
According to a fourth aspect of the present invention, in the third aspect of the present invention, the atmospheric block provided in the overflow pipe portion of the reservoir tank fits the overflow pipe provided in a part of the reservoir tank. It is a protrusion .
[0020]
According to the first and second aspects of the present invention, when the water injection cap of the radiator is removed, the atmosphere enters the pipe from the atmospheric opening provided in a part of the pipe or the reservoir tank. The cooling water in the tank cannot be sucked up. Therefore, it does not flow out. According to the third and fourth aspects of the present invention, since the atmosphere cannot be sucked from the overflow pipe portion, the cooling water in the reservoir tank does not flow to the radiator side.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described below with reference to FIG. Reference numeral 9 denotes a reservoir tank, which has a water injection port 9a at the top, and has a structure in which a water injection cap 16 is fitted into the water injection port 9a. The reservoir tank 9 is marked with “FULL” and “LOW” so that the amount of cooling water is within this range. A pipe 11 having a lower end opened near the bottom of the reservoir tank 9 is provided inside the reservoir tank 9.
[0022]
The upper end of the pipe 11 is fitted in a portion directed downward of an L-shaped pipe portion 16 a formed in the water injection cap 16. A pipe 14 is fitted to the side portion of the pipe portion 16 a and communicates with the upper tank 12 of the radiator 8. The water injection cap 16 has another pipe portion 16b having one end communicating with the inside of the reservoir tank 9, and the base end of the overflow pipe 32 is fitted into the pipe portion 16b. The tip of the overflow pipe 32 is open to the atmosphere.
[0023]
A part of the water injection cap 16 is provided with an atmospheric opening 16c by projecting a part of the L-shaped pipe part 16a. The atmospheric opening 16c is covered with a rubber cap 33. When removed, the pipe portion 16a communicates with the atmosphere, and when covered, the atmosphere is blocked from the atmosphere. . In this embodiment, when the cap 33 is removed and the pipe portion 16a communicates with the atmosphere, it functions as a blocking means for blocking the flow of cooling water between the upper tank 12 and the reservoir tank 9 of the radiator 8. .
[0024]
In this embodiment, the cap 33 is put on in the normal state. Then, air does not enter the inside of the pipe portion 16a from the atmospheric opening portion 16c. Therefore, if the upper tank 12 side of the radiator 8 becomes a negative pressure, the cooling water passes through the pipe 11, the pipe portion 16a and the pipe 14 to the upper tank 12 side. Flowing. At this time, air is sucked from the overflow pipe 32.
[0025]
When removing the water injection cap 13 of the radiator 8 due to the need for maintenance or the like, the cap 33 is removed from the atmospheric opening 16c as shown in FIG. Then, air enters the pipe portion 16a and the pipe 11, the pressure in the reservoir tank 9 becomes the same as the atmospheric pressure, and the cooling remaining in the pipe 14 even when the water injection cap 13 of the radiator 8 is removed. Only water flows to the radiator 8 side, and other cooling water does not flow to the radiator 8 side. This prevents the cooling water from flowing out.
[0026]
FIG. 3 shows another example of the embodiment of the present invention. In this embodiment, the blocking means for blocking the flow of the cooling water between the upper tank 12 and the reservoir tank 9 of the radiator 8 is formed by an atmospheric block provided in the overflow pipe 32 of the reservoir tank 12. Specifically, as shown in the figure, a projection 34 for fitting the overflow pipe 32 is provided in a part of the reservoir tank 12, and the tip of the overflow pipe 32 is fitted to the projection 34. Since this fitting is performed densely so that air does not enter from this portion, the outer dimension A of the protrusion 34 is slightly larger than the inner diameter B of the overflow pipe 32.
[0027]
In this embodiment, when the maintenance inspection or the like is necessary and the water injection cap 13 of the radiator 8 is removed, the tip of the overflow pipe 32 is fitted to the protrusion 34 formed on the reservoir tank 9 as shown in FIG. . Then, since the overflow pipe 32 is cut off from the atmosphere, even if the water injection cap 13 of the radiator 8 is removed and the pipe 14 is opened to the atmosphere, the cooling water does not flow to the radiator 8 side. This prevents the cooling water from flowing out.
[0028]
In the embodiment described above, the structure of a part of the water injection cap 16 of the reservoir tank 9 is changed or the protrusion 34 is provided on the reservoir tank 9, but in the present invention, the upper tank 12 and the reservoir tank 9 of the radiator 8 are provided. The blocking means for blocking the flow of the cooling water between the two is not limited to this, for example, a three-way cock is attached to the portion of the water injection cap 16, thereby allowing air to enter the pipe 14 side, Or you may switch so that it may interrupt | block.
[0029]
【The invention's effect】
Since the present invention is an engine cooling apparatus configured as described above, according to the first aspect of the present invention, the blocking of the cooling water flow between the upper tank and the reservoir tank of the radiator is performed. Means , that is, the part of the pipe that connects the interior of the reservoir tank and the upper tank, or the atmospheric opening provided in the reservoir tank ensures that the cooling water flows out of the reservoir tank when the upper tank water injection cap is removed. can be prevented in, by very simple structure the number of components is small, it is possible to obtain the great effect of the cooling water outflow prevention.
According to the second aspect of the present invention, the atmospheric opening can be returned to the normal state only by closing it with the cap, and the structure is extremely simple.
Further, according to the invention described in claim 3, by means of a shut-off means for blocking the flow of the cooling water between the upper tank and the reservoir tank of the radiator, that is, by the atmosphere closing portion provided in the overflow pipe portion of the reservoir tank, It is possible to reliably prevent cooling water from flowing out of the reservoir tank when the upper tank water injection cap is removed.
Furthermore, according to the invention described in claim 4, since the atmosphere closing portion is a projection for fitting an overfree pipe provided in a part of the reservoir tank, the cooling can be performed by a simple structure with a small number of parts. A great effect of preventing water outflow can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a main part of an example of an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing a different state of that of FIG.
FIG. 3 is a cross-sectional view showing a main part of another example of the embodiment of the present invention.
4 is a cross-sectional view showing a different state of that of FIG. 3;
FIG. 5 is a side view showing a part of a lorry to which the present invention is applied in a transparent state.
6 is an enlarged side view of the front room portion of FIG. 5. FIG.
FIG. 7 is a sectional view showing a general structure of a radiator upper tank and a water injection cap.
8 is a cross-sectional view showing a different state of that of FIG.
FIG. 9 is a cross-sectional view showing a further different state from that of FIG. 7;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Lorry car 8 Radiator 9 Reservoir tank 11 Pipe 12 Upper tank 13 Water injection cap 14 Pipe 16 Water injection cap 16a Pipe part 16b Pipe part 16c Atmospheric opening 32 Overflow pipe 33 Cap

Claims (4)

In an engine cooling apparatus in which a reservoir tank is disposed above a radiator having a cap for water injection provided in an upper tank, and the inside of the reservoir tank and the upper tank of the radiator are communicated with each other by a pipe. The tank is provided with a blocking means for blocking the flow of cooling water between the upper tank and the reservoir tank of the radiator, and the blocking means is formed by an atmospheric opening provided in a part of the pipe or the reservoir tank. An engine cooling system characterized by that . 2. The engine cooling device according to claim 1 , wherein an atmospheric opening provided in a part of the pipe or a reservoir tank can be closed with a cap. In an engine cooling apparatus in which a reservoir tank is disposed above a radiator having a cap for water injection provided in an upper tank, and the inside of the reservoir tank and the upper tank of the radiator are communicated with each other by a pipe. The tank part is provided with a blocking means for blocking the flow of cooling water between the upper tank and the reservoir tank of the radiator, and the blocking means is formed by an atmospheric block provided in the overflow pipe part of the reservoir tank. Engine cooling device characterized by.   4. The engine cooling apparatus according to claim 3, wherein the air blocking portion provided in the overflow pipe portion of the reservoir tank is a projection for fitting the overflow pipe provided in a part of the reservoir tank.

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