JPS6123608Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a cooling device for an internal combustion engine that improves fuel efficiency, exhaust characteristics, and drivability.

As a conventional cooling device of this type, for example, the first
There is something like the one shown in the figure (Nissan Motor Co., Ltd., March 1978, Automotive Engineering (Engine) No.
(See page 79). In such a cooling system, the thermostat 1 is closed when the engine cooling water temperature is below a predetermined value, so the cooling water pushed out from the water pump 2 flows through the cylinder block 3 and cylinder head 4 as shown by the arrow. Instead of passing through the rear radiator 5, the cooling water passed through a bypass hole 6 and was led back to the water pump inlet 7, thereby forming a first passage for the cooling water.

To further explain this with the partially enlarged cross-sectional view in FIG.
, and was led from the water pump outlet 8 to the water jacket inlet 9.

Note that when the temperature of the cooling water exceeds a predetermined value (first predetermined value), it flows to the inlet of the water pump 2 via the cylinder block 3, cylinder head 4, thermostat 1, and radiator 5, and flows through the second passage. The configuration is the same as before.

However, in such conventional cooling systems, even when the engine cooling water temperature is low, the water pump 2 continues to rotate and the cooling water is forced to circulate inside the engine. This has the problem of radiating heat generated from the engine and slowing down the rate of increase in coolant temperature, which slows down the rise in engine temperature and leads to deterioration in fuel efficiency, exhaust characteristics, and drivability.

This idea was made by focusing on such conventional problems, and when the engine cooling water temperature is below a predetermined value, at least the cooling water passage at the water pump inlet and outlet is communicated, so that the cooling water flows between the cylinder block and the cylinder block. The purpose of the present invention is to solve the above problem by preventing the fluid from flowing into the cylinder head.

This invention will be explained in detail below based on the drawings.

FIG. 3 is an enlarged sectional view of essential parts showing an embodiment of this invention. In this figure, the same reference numerals as in FIG. 2 indicate the same components, and 10 is a radiator outlet waterway;
Reference numeral 11 denotes a communication passage, which provides electrical continuity between the water pump outlet 8 and the water pump inlet 7 when the engine is cold. Reference numeral 12 denotes a thermostat for opening and closing the water jacket inlet 9 and the communication passage 111 according to the cooling water temperature.

The details and operating conditions of this thermostat 12 will be explained with reference to FIGS. 4 and 5. FIG. 4 shows the state when the cooling water temperature is low, that is, the non-operating state, and FIG. 5 shows the state when the cooling water temperature is high, that is, the operating state. The operating temperature (second predetermined value) of the thermostat 12 is suitably lower than the valve opening temperature of 80°C (first predetermined value) of the conventional thermostat 11 shown in FIG. 1, for example, about 60°C. This difference is not absolute, and may be equal to, but never exceed, the first predetermined value.

In Figures 4 and 5, 13 is a cylinder;
It has a piston 14, a wax W is provided on the circumferential surface inside the cylinder 13, and the inside is filled with synthetic rubber G. 15 is a valve integrated with the cylinder 13, which closes and opens the water jacket inlet 9 of the cylinder block; 16 is a valve which opens and closes the communication passage 11; both valves move integrally; and the valve 15 is a spring-mounted valve. 17
It is in close contact with the guide 18. The thermostat 12 is configured as described above.

Next, the action will be explained. In FIG. 4, when the engine cooling water temperature is low, the valve 15 integrated with the cylinder 13 is in close contact with the guide 18 due to the spring force of the spring 17 because the wax W is contracted, and the water jacket inlet 9 is closed. Closed. Since the other valve 16 does not block the communication passage 11, the cooling water pushed out from the water pump outlet 8 in FIG. 3 is guided to the water pump inlet 7 again through the communication passage 11. As a result, when the engine is cold, the cooling water does not circulate through the cylinder block and cylinder head, causing the engine temperature to rise quickly and greatly improving fuel efficiency, exhaust characteristics, and drivability.

Next, when the engine cooling water temperature exceeds a predetermined value, the fifth
As shown in the figure, as the wax W expands and the synthetic rubber G conversely contracts, the cylinder 13 moves upward on the piston 14. Since the valve 15, which is made integrally with the cylinder 13, also overcomes the spring force of the spring 17 and moves upward, a gap 19 is created between the valve 15 and the guide 18, and the cooling water from the water pump outlet 8 flows through the gap. 19 to the water jacket inlet 9, and circulates through the cylinder block and cylinder head. When the engine cooling water temperature further rises, the valve 16 completely shuts off the communication passage 11 and the entire amount of cooling water from the water pump outlet 8 is guided to the water jacket inlet 9.

FIGS. 6 and 7 are sectional views of main parts showing other embodiments of this invention, respectively.

The embodiment shown in FIG. 6 is an example in which the thermostat 12 is provided on the side of the bypass hole 6, and its operation is the same as that of the embodiment shown in FIG. That is, thermostat 1
When the temperature of water jacket 2 is below the second predetermined value, the bypass hole 6, which is the outlet of the water jacket inlet 9, is closed, and the communication passage 11 is open, so that cooling water does not flow into the water jacket inlet 9. does not flow in, so the first passage remains stopped and warm-up is accelerated. Further, when the temperature of the cooling water exceeds the second predetermined value, the bypass hole 6 is opened and the communication passage 11 is closed, so that normal operation resumes.

In the embodiment shown in FIG. 7, a valve 20 for opening and closing the bypass hole 6 is provided between the cylinders 13 and 16 of the thermostat 12, and the operation is the same as in the previous embodiments. In addition, in this embodiment, the thermostat 12 also serves as the conventional thermostat 1 (see FIG. 1), so the temperatures at the first predetermined value and the second predetermined value are almost the same, and if the temperature is below this predetermined value, As shown in the figure, the outlet of the water jacket inlet 9 is closed by the valve 20 of the thermostat 12 (15 in FIGS. 4 and 5), and the valve 16 is opened to open the communication passage 11. Because it is open, the cooling water in the cylinder block jacket remains stopped and warm-up is accelerated.
Furthermore, when a predetermined value is exceeded, the three valves simultaneously move to the right, opening the first and second passages.

Although each of the above embodiments has been described using the thermostat 12, this invention is not limited to this, and the present invention is not limited to this, but can also be implemented using a temperature detection means that directly or indirectly detects the temperature of the cooling water and a solenoid valve. Alternatively, a similar effect can be obtained by controlling using a bimetal type thermostat.

As explained above, this invention provides a communication path that communicates the water pump inlet and outlet, and further includes a cooling water temperature detection means for detecting the temperature of the cooling water, and a cooling water temperature detection means that controls the temperature of the cooling water. Since a valve is provided that opens the communication passage when the value is below a predetermined value and closes the communication passage when the predetermined value is exceeded, the cooling water from the water pump is circulated to the cylinder block and cylinder head when the engine is cold. As a result, the engine temperature rises earlier than before, resulting in significant improvements in fuel efficiency, exhaust characteristics, and drivability.

[Brief explanation of the drawing]

Fig. 1 is a system diagram of a conventional cooling system, Fig. 2 is a partially enlarged sectional view of Fig. 1, Fig. 3 is a sectional view of essential parts showing an embodiment of this invention, Figs. 4 and 5. FIG. 3 is a cross-sectional view of a main part for explaining details and operating conditions, and FIGS. 6 and 7 are cross-sectional views of main parts showing other embodiments of this invention. In the figure, 2 is a water pump, 7 is a water pump inlet, 8 is a water pump outlet, 9 is a water jacket inlet, 10 is a radiator outlet waterway, 1
1 is a communicating path, 12 is a thermostat, 13 is a cylinder, 14 is a piston, 15, 16, and 20 are valves, 17 is a spring, 18 is a guide, and 19 is a gap.

Claims (1)

[Scope of utility model registration request] From the water pump outlet to the cylinder block,
A first passage in which cooling water circulates through the cylinder head, a thermostat, and a bypass hole to the water pump inlet; and when the temperature of the cooling water exceeds a first predetermined value, the thermostat begins to open and the water pump flows from the water pump outlet to the cylinder. A second section in which cooling water circulates through the block, cylinder head, thermostat, and radiator to the water pump inlet.
A cooling device for an internal combustion engine, comprising: a communication passage that directly communicates the inlet and outlet of the water pump; a cooling water temperature detection means for detecting the temperature of the cooling water; and a cooling water temperature detection means that is controlled by the cooling water temperature detection means to When the temperature of the water is below a second predetermined value lower than the first predetermined value, the communication passage is opened and the first passage is closed; when the temperature exceeds the second predetermined value, the communication passage is closed and the first passage is closed. A cooling device for an internal combustion engine, comprising a valve that opens one passage.