JPH0517383Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an engine cooling system in which a thermostat is mounted on a cylinder block.

(Prior Art) Generally, in an engine cooling system, a thermostat that adjusts the cooling water circulation system according to the temperature of the cooling water is installed and supported separately from the cylinder block, and is supported by a pipe member. It is connected to the cooling water passage of each part (for example,
Publication No. 28218).

In addition, since the exhaust manifold that guides exhaust gas from the engine cylinder head is in a high temperature state, installing a thermostat near this exhaust manifold may cause the thermostat to malfunction and the cooling water passage connected to the thermostat to be damaged. Since it requires a heat-resistant structure, it is designed to be avoided as much as possible.

Furthermore, as shown in Japanese Patent Application Laid-Open No. 58-206820, if the thermostat is installed directly on the cylinder block, the engine can be made more compact and the supporting rigidity of the thermostat can be improved.

(Problem to be solved by the invention) However, for example, if the thermostat is installed in the cylinder block on the side where the exhaust manifold is installed, due to layout and functional factors of each mechanical part, It is necessary to attach an insulating member against radiant heat from the exhaust manifold to the cooling water hose connected to this thermostat, which increases the number of parts, makes the parts larger, and makes layout difficult.

Therefore, in view of the above circumstances, the present invention aims to provide an engine cooling device that can deal with heat damage from the exhaust manifold to the cooling water hose connected to the thermostat installed on the exhaust side side of the cylinder block. This is the purpose.

(Means for Solving the Problems) The cooling device of the present invention includes an exhaust manifold that extends substantially vertically on the side of the cylinder block, and further includes an exhaust manifold located in front of the exhaust manifold on the side of the cylinder block. In an engine in which first and second auxiliary machines are arranged above and below adjacent to the thermostat, a thermostat case for accommodating the thermostat is formed near the auxiliary machine on the side surface of the cylinder block on the exhaust manifold side, and A cover with a cooling water inlet is removably provided in the case, and a cooling water hose connected to the cooling water inlet of the cover is extended through between the first auxiliary machine and the second auxiliary machine and connected to the radiator. It is characterized by:

(Function) In the above cooling device, when a thermostat is installed in an engine in which an exhaust manifold is disposed extending substantially vertically to the side of a cylinder block, a thermostat case housing the thermostat is attached to the cylinder block. A cooling water hose connected to a cover installed in the thermostat case is installed near the auxiliary equipment arranged above and below adjacent to the front of the exhaust manifold on the side of the block, and is connected to the alternator, cooler compressor,
It is extended between the first and second auxiliary equipment arranged above and below the power steering compressor, etc., and connected to the radiator, so that a part of the auxiliary equipment is connected to the exhaust manifold and the cooling water hose. Located in between, these auxiliary equipment block and protect a portion of the radiant heat from the exhaust manifold, reducing the heat load on the cooling water hose and preventing its thermal damage. Alternatively, there is no need to use a special heat-resistant cooling water hose, resulting in a reduction in the number of parts and an advantage in layout.

(Example) Hereinafter, an example of the present invention will be described along with the drawings. Figure 1 is a sectional view of the thermostat case, Figure 2 is a side view, Figure 3 is a partially sectional side view of the cylinder block, and Figure 4 is a sectional plan view of the cylinder block in the thermostat case. be.

The cylinder block 1 has a skirt part 1b connected to both sides of the lower part of the upper cylinder part 1a, and a cylinder head 2 is fastened to the upper part of the cylinder part 1a.
A piston (not shown) is fitted into the bore 1c of the cylinder portion 1a so as to be able to reciprocate up and down, and the skirt portion 1
A main bearing portion 4 is located below the cylinder portion 1a at the center of b.
will be placed. The main bearing portion 4, the cylinder portion 1a and the skirt portion 1b are connected by a bulkhead portion 5 in the form of a partition wall.

The cylinder head 2 is connected to an exhaust manifold 6 that guides exhaust gas from each cylinder.
are also bent rearward and gathered at the rear flange portion 6a. On the other hand, first and second auxiliary machines 7 and 8 such as an alternator and a compressor for a cooler are arranged above and below on the front side of the cylinder block 1 where this exhaust manifold 6 is arranged, and the crankshaft (Fig. (not shown) via belt 9.

A water pump 11 (see FIG. 3) is installed on the front side of the cylinder block 1, and the water pump 11 is attached to a water pump body 12 formed on the cylinder block 1 and fixed to a pump shaft 13. An impeller 14 is provided. Further, the pump shaft 13 is supported by a chain case 15 and a pump cover 16 attached to the front end surface of the cylinder block 1, and a pulley 17 is attached thereto.

The water pump body 12 is formed integrally with the cylinder block 1 so as to protrude from the side of the front end surface thereof. On the back side of the water pump body 12, a thermostat case 20 in which the thermostat 19 is attached is installed, and the thermostat case 20 is attached to the first auxiliary machine 7.
In the vicinity of the water pump body 12
The cylinder block 1 is integrally formed so as to connect the rear surface of the cylinder block 1 with the side wall of the cylinder block 1.

Suction side port 11a of the water pump 11
communicates with the thermostat case 20 from the side, and the center of the thermostat case 20 is arranged at a position offset downward from the center of the suction side port 11a of the water pump.

On the other hand, a discharge port 11b of the water pump 11 is formed to communicate with a cooling water passage 21 on the outer periphery of the bore of the cylinder portion 1a. Further, the thermostat case 20 has a downstream end 22a opened at the center of the bottom of a bypass passage 22 integrally formed with the cylinder portion 1a.
Communication between the water pump 11 and the suction side port 11a of the water pump 11 is opened and closed by a thermostat 19.
Furthermore, a heater return passage connection port 20a is formed in the thermostat case 20, facing the water pump suction side port 11a and extending substantially coaxially with the suction side port 11a.

A cap-shaped cover 23 that covers the thermostat 19 is detachably attached to the thermostat case 20, and the cover 23 is provided with a cooling water inlet 23a. A radiator return passage 25 by a hose 24 is connected. The cooling water hose 24 passes from the cooling water inlet 23a of the cover 23 between the first auxiliary machine 7 and the second auxiliary machine 8, and connects to the radiator 31.
(See FIG. 5) is connected to the drain port 31b. Communication between the radiator return passage 25 and the suction side port 11a of the water pump 11 is also opened and closed by the thermostat 19, and the bypass passage 2
2 to be opened and closed.

The bypass passage 22 extends longitudinally in the lower part of the cylinder portion 1a, and has an inlet 22b opened in the side wall of the cylinder block 1. Furthermore, an oil gear gallery 26 that similarly extends in the longitudinal direction of the cylinder block 1 is formed at the lower portion of the cylinder portion 1a on the opposite side to the bypass passage 22. Note that balancer shafts 27, 27 are provided on both sides of the upper portion of the main bearing portion 4.

Next, FIG. 5 shows a schematic configuration of the cooling system.
The cooling water discharged from the discharge side port 11b of the water pump 11 installed on the front end face of the cylinder block 1 flows into the cylinder section 1 of the cylinder block 1.
The cooling water flows into the cylinder head 2 from the cooling water passage 21 on the outer periphery of the bore a, and branches into a radiator supply passage 30 and a bypass passage 22 from an outlet 29 at the rear end of the cylinder head 2. The bypass passage 22 starts from the inlet 22b on the side of the cylinder block 1, passes through the bypass passage 22 inside the cylinder block 1, and connects to the water pump 11 via the thermostat case 20.
It communicates with the suction side port 11a.

Further, the radiator feed passage 30 is connected to an inlet 31a of the radiator 31, and a radiator return passage 25 from the drain port 31b of the radiator 31 is connected to the cooling water inlet 23a of the cover 23 via the thermostat case 20. , is communicated with the water pump 11. Furthermore, a heater passage 3 led out from the other side of the cylinder block 1
2 passes through a heater core 33, a heater return passage 34 is connected to a connection port 20a in the thermostat case 20, and flows into the suction side port 11a of the water pump 11.

Connections between the bypass passage 22 and the radiator return passage 25 and the suction side port 11a of the water pump 11 are switched open and closed by a thermostat 19 housed in a thermostat case 20.

When the engine temperature is low, the thermostat 19 closes the radiator return passage 25 while opening the bypass passage 22, allowing the cooling water that has flowed through the cylinder block 1 and the cylinder head 2 to flow through the bypass passage 22. The water is circulated by bypassing the radiator 31 and returning to the water pump 11.

When the engine is cold, the cooling water flowing through the bypass passage 22 is heated by radiant heat from the exhaust manifold 6 disposed near the bypass passage 22, and the temperature of the cooling water increases quickly. Opportunity is encouraged.

On the other hand, when the engine temperature rises, the thermostat 19 closes the bypass passage 22, opens the radiator return passage 25, cools the cooling water that has passed through the cylinder block 1 and cylinder head 2 in the radiator 31, and then closes the thermostat. 19
is fed again by the water pump 11 from
This cools and circulates the engine.

According to the above embodiment, by forming the thermostat case on the cylinder block, the supporting rigidity of the thermostat and the rigidity of the cylinder block can be improved. In particular, the number of parts is reduced compared to separately mounting the thermostat, and the number of connecting parts between the mounting part and the passage is reduced by integrally forming the thermostat, making it easier to ensure sealing performance. Further, by forming the thermostat case at the connecting portion between the cylinder portion and the skirt portion of the cylinder block, the rigidity of the entire cylinder block can be improved.

Furthermore, by installing the thermostat in the back space of the part where the water pump body protrudes, space can be used effectively, and together with the heat shielding structure of the cooling water hose, the system can be made more compact.

(Effects of the Invention) According to the present invention as described above, the cooling water hose connected to the cover of the thermostat case formed in the cylinder block is extended between the first and second accessories arranged adjacent to each other in front of the exhaust manifold and connected to the radiator, and part of the accessories is interposed between the cooling water hose and the exhaust manifold to reduce the amount of heat received from the exhaust manifold and lighten the thermal load, thereby making it possible to block the radiant heat from the exhaust manifold to the cooling water hose without the use of any special insulation material.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the thermostat case of an engine according to an embodiment of the present invention, Fig. 2 is a side view of the engine, Fig. 3 is a sectional side view of the main part of the cylinder block, and Fig. 4 is a sectional view of the thermostat case. A cross-sectional plan view of the case portion, FIG. 5 is a schematic configuration diagram of the cooling system. 1... Cylinder block, 1a... Cylinder part, 1b... Skirt part, 2... Cylinder head, 6... Exhaust manifold, 7, 8... Auxiliary equipment,
11...Water pump, 12...Water pump body, 19...Thermostat, 20...Thermostat case, 22...Bypass passage, 2
3...Cover, 23a...Cooling water inlet, 24...
...Cooling water hose, 25...Radiator return passage, 31...Radiator.

Claims (1)

[Claims for Utility Model Registration] An exhaust manifold is disposed on the side of the cylinder block and extends substantially in the vertical direction, and a first and a first exhaust manifold are provided above and below adjacent to the front of the exhaust manifold on the side of the cylinder block. In the engine in which two auxiliary machines are arranged, a thermostat case for accommodating a thermostat is formed near the auxiliary machine on a side surface of the cylinder block on the exhaust manifold side, and a cooling water inlet is formed in the thermostat case. a removable cover, and a cooling water hose connected to a cooling water inlet of the cover extends between the first auxiliary equipment and the second auxiliary equipment and is connected to the radiator. An engine cooling system featuring: