JPH076382B2 - Water cooling system for internal combustion engine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a water-cooled cooling device for an internal combustion engine, and more particularly to a water-cooled cooling device for heating an intake system with cooling water.

2. Description of the Related Art Generally, as a water-cooled cooling device for an internal combustion engine for automobiles,
A forced circulation pressurization method is adopted, and an example thereof is a bottom bypass method.

Explaining the outline, a water jacket communicating with each other through a communication hole is formed inside a cylinder block and a cylinder head of a gasoline engine, and the cooling water that has absorbed heat in each of the water jackets is used during normal operation. By the action of the pump, it is pumped to the radiator through the cooling water outlet passage and radiates heat there, and is further forcibly introduced into the cylinder block side water jacket through the cooling water inlet passage and flows to the cylinder head side water jacket. To cool each part of the engine.

On the other hand, when the water temperature is low, such as during cold start, the cooling water outlet passage is blocked by the operation of the thermostat that maintains the engine's proper operating temperature.Therefore, the cooling water does not pass through the radiator but passes through the bypass passages to the water passages. It circulates in the jacket.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention By the way, in general, in a gasoline engine, in order to improve the ignitability of the air-fuel mixture by a spark plug and improve the output of the engine at the time of cold start, the gas is supplied into the combustion chamber. It is desirable to preheat the intake air sufficiently with cooling water or the like.

Therefore, for example, as in the technique described in Japanese Utility Model Laid-Open No. 59-170627, a cooling water introducing pipe for taking out cooling water from a radiator and introducing it into the engine body is provided below the intake manifold and at the same time. In addition to being arranged so as to intersect with each branch part of the above, one end of the bypass pipe whose one end is connected to the thermostat valve in the middle of the cooling water introduction pipe is connected to the cooling water passage in the riser portion of the intake manifold. It is provided.

However, in the device described in such a publication, since only the cooling water introducing pipe is simply arranged below the intake manifold, the intake air cannot be sufficiently warmed when the engine is cold.
Further, the cooling water passage must be formed in the riser portion by so-called casting, etc., which not only requires such special heating means but also complicates the structure, which complicates the manufacturing work and raises the cost. To be forced.

Means for Solving the Problems The present invention has been devised in view of the actual situation of the conventional water-cooled cooling device, and provides an intake volume chamber along a longitudinal direction of the engine at a side portion of an engine body, and A bypass pipe for introducing cooling water discharged from one end side of the engine main body to a thermostat valve provided at the other end side of the engine main body is arranged closely along the longitudinal direction of the intake volume chamber, and flows out from the thermostat valve. The cooling water supply pipe for returning the cooling water to the one end side of the engine body is arranged substantially parallel to the bypass pipe and close to the intake volume chamber.

According to the present invention having the above-described configuration, for example, at the time of starting the cold machine, the cooling water discharged from one end side of the engine body and flowing into the bypass pipe passes through the vicinity of the intake volume chamber while radiating heat from the bypass pipe, and then the thermostat After reaching the valve, the thermostat valve makes a U-turn to flow into the cooling water supply pipe, and again radiates heat from the cooling water supply pipe and returns to the engine body through the vicinity of the intake volume chamber. Therefore, a double amount of heat is released by the bypass pipe and the cooling water supply pipe, the intake volume chamber is efficiently heated, and as a result, the intake air passing through the intake volume chamber can be positively and efficiently warmed.

Moreover, since the bypass pipe and the cooling water supply pipe are simply arranged in parallel in the longitudinal direction of the intake volume chamber, the structure thereof is simplified, and the manufacturing cost does not significantly increase.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

1 to 3 show an embodiment of the present invention, in which 1 is an in-line 4-cylinder gasoline engine which is arranged in the engine room in the vehicle width direction, that is, horizontally, and 2 is arranged in front of the engine 1. A radiator 3, a cylinder block having a water jacket 4 inside, a cylinder head 5 provided at an upper end of the cylinder block 3 and having a water jacket 6 inside, an exhaust manifold 7 and a downstream side 8 of an intake passage The intake volume chamber 9 is an intake manifold disposed above the intake volume chamber 8, and the cylinder block 3 has a front end 3a in which a water pump 10 is integrally housed and disposed. A thermostat valve 11 is connected to the end 3b by bolts 12 ...

The intake volume chamber 8 has a substantially box shape extending laterally along the outer surface of the upper portion of the cylinder block 3, and a throttle body 15 having a throttle valve 14 housed therein is attached to a bolt 16 at a side mounting flange 13. Are connected to each other, and a flange-shaped mounting portion 17 having four intake holes at equal intervals in the lateral direction is formed on the upper side. The intake volume chamber 8 is connected to and supported by the cylinder block 3 and the cylinder head 5 by four brackets 18, 19, 20, 21. Specifically, the lower end portion of the mounting flange 13 is connected and supported to the transmission coupling flange portion at the rear end of the cylinder block 3 via the first bracket 18 having a substantially triangular shape, and the upper end portion of the mounting flange 13 is also substantially It is connected to and supported by the rear end outside portion of the cylinder head 5 via a second bracket 19 bent in a crank shape. Further, the lower portion of the mounting portion 17 on the rear end side is connected and supported to the lower end of the skirt portion on the rear end side of the cylinder block 3 through a third bracket 20 bent in a substantially L shape, and also on the front end side of the mounting portion 17. The lower portion is connected and supported to the lowermost end of the skirt portion on the front end side of the cylinder block 3 via a fourth bracket 21 bent in a substantially arc shape.

As shown in FIG. 3, the intake manifold 9 is provided with four branch portions 22 ... Which are bent downward in a substantially arc shape, and the upper ends of the branch portions 22 ... The mounting flange 23 is integrally provided with a mounting flange 25, which is mounted via two stud bolts 24a at both ends and six bolts 24b, while the mounting portion of the intake volume chamber 8 is provided at the lower end. Similarly, 17 is integrally provided with a mounting portion 27 which is mounted via two stud bolts 26a at both ends and three bolts 26b. The entire intake manifold 9 is detachably attached to the cylinder head 5 and the intake volume chamber 8 via the mounting flanges 25 ... And the mounting portion 27. A substantially inverted concave space 50 is formed inside the cylinder block 3, the cylinder head 5, the intake volume chamber 8 and the intake manifold 9.

A boss portion 29 having a mounting hole for the fuel injection valve 28 is integrally formed at the upper end of each mounting flange 25 of each branch portion 22 and the joint portion, and a fuel pipe 30 that connects the mounting holes. Are arranged along the lateral direction.
Both sides of the boss 30 are pressed and supported by the support members 31, 31 against the boss portion 29 ... Outer edge.

Further, an accelerator drum 33 is fixed to the outside of the rear end side branch portion 22 by a bolt 32.
The reference numeral 33 is connected to the throttle drum 34 of the throttle valve 14 via a linkage (not shown) arranged in the vertical direction.

Further, as shown in FIG. 1, the cooling water outlet end 35 provided on the outer surface on the front end side of the cylinder head 5 has a cooling water outlet pipe 36.
Is connected to the cooling water inlet end 37a provided at the upper end of the inner surface of the radiator 2. On the other hand, the cooling water outlet end 37b provided at the lower end of the inner surface of the radiator 2 has a cooling water introduction pipe 38
Is connected to the cooling water inlet portion 11a of the thermostat valve 11, and further the cooling water outlet portion 11b formed on the side portion of the thermostat valve 11 is connected to the water pump 10 via the cooling water supply pipe 39 made of a metal pipe. Is connected to the suction port 10a. Further, a bypass pipe 40 made of a metal pipe is juxtaposed on the side of the cooling water supply pipe 39.

That is, the cooling water supply pipe 39 is connected to the cylinder block 3
Cooling of the thermostat valve 11 by wrapping around the side of the cylinder head 5 from the rear end side 3b and extending in the direction of the front end 3a, one end 39a of which is welded to the flange 47 of the thermostat valve 11. It is firmly connected to the water outlet 11b, while the other end 39b is connected to the water pump inlet 10a via a joint 48 of a rubber tube.

On the other hand, one end 40a of the bypass pipe 40 is a rubber tubular joint 4
Bypass water outlet 3c near the water pump 10
And the other end 40b is firmly connected to the flange portion 47 by welding and connected to the bypass water inlet portion 11c of the thermostat valve 11, respectively, and substantially the entire cooling water supply pipe 3 is provided.
It is arranged in parallel with 9.

The cooling water supply pipe 39 and the bypass pipe 40 are housed in the space 50 of the reverse concave shape constituted by the cylinder block 3, the cylinder head 5, etc., and extend in the longitudinal direction over substantially the entire length of the intake volume chamber 8. They are located close to each other. Also,
The cooling water supply pipe 39 and the bypass pipe 40 are connected to the joint side portion of the cylinder block 3 and the cylinder head 5 by a support bracket 41 bent in a substantially V shape. Therefore, the binding force of both 39 and 40 is strengthened, and the vibration due to the vibration input from the cylinder block 3 and the cylinder head 5 can be sufficiently prevented.

Therefore, according to this embodiment, when the engine 1 is cold-started, the thermostat valve 11 is closed to shut off the introduction of the cooling water from the radiator 2, so that the cylinder head side water jacket whose water temperature is rising The cooling water in 6 flows into the bypass pipe 40 from the bypass water outlet part 3c as shown by the solid line arrow in FIG. 1, and while radiating heat there, it passes through the vicinity of the intake volume chamber 8 and the intake manifold 9 and the thermostat. It is sent into the valve 11. Furthermore, from here U
It turns and flows into the cooling water supply pipe 39 from the cooling water outlet portion 11b, further radiates heat there, and again passes through the vicinity of the intake volume chamber 8 and the like, and enters the cylinder block side water jacket 4 via the water pump 10. Circulate. Therefore, the intake volume chamber 8 and the intake manifold 9 are positively and efficiently heated by the heat radiated from the cooling water in both the bypass pipe 40 and the cooling water supply pipe 39. Particularly, in the intake volume chamber 8, since the residence time of the intake air is long, the heating efficiency of the intake air is further improved. Therefore, the temperature of the intake air flowing through the intake volume chamber 8 and the like rapidly rises and is supplied to the combustion chamber as it is. As a result, the ignitability of the air-fuel mixture is improved, and higher engine output can be obtained.

On the other hand, since the thermostat valve 11 is opened after warming up, the cooling water in the water jacket 6 on the cylinder head side is cooled by the cooling water outlet pipe 36-radiator 2-cooling water introduction pipe 38-thermostat valve as shown by the broken line in FIG. 11-cooling water supply pipe 39-circulates in the water jacket 4 on the cylinder block side and the water jacket 6 on the cylinder head side via the water pump 10.

Further, the cooling water supply pipe 39 and the bypass pipe 40 are connected to the intake volume chamber 8
Since it is arranged in the inner space 50 such as the above, the dead space can be effectively utilized. Further, since the thermostat valve 11 is arranged on the rear end portion 3b side of the cylinder block 3, maintenance and inspection work of the thermostat valve 11 is facilitated. Become.

Further, since the intake volume chamber 8 is connected and supported to the cylinder block 3 and the cylinder head 5 by the four brackets 18 to 21, its supporting rigidity is increased and the amplified vibration of the throttle body 15 is sufficiently suppressed. As a result, the deterioration of the sealing performance between the throttle body 15 and the intake volume chamber 8 can be prevented.

Furthermore, since the intake manifold 9 is detachably attached to the cylinder head 5 and the intake volume chamber 8 by itself,
Not only the work such as maintenance and inspection of the equipment near the engine 1 and the intake manifold 9 can be facilitated, but also the piping work of the cooling water supply pipe 39 and the bypass pipe 40 in the space 50 becomes very easy.

Incidentally, on the downstream side of the bypass pipe 40 and on the upstream side of the cooling water supply pipe 39, as shown in FIG.
The inlet pipe 42 and the outlet pipe 43 of the bypass pipe 40 are connected.
The cooling water in the inside is sent to the heater device 46 and returned from there to the cooling water supply pipe 39. Therefore, when the heater is used, the relatively high temperature cooling water from the heater device 46 reciprocates in the bypass pipe 40 and the cooling water supply pipe 39, so that the intake air heating effect in the intake volume chamber 8 is further promoted.

The present invention is not limited to the configuration of the above-described embodiment, and for example, the bypass circuit can be configured by a different bypass water supply pipe without using the cooling water supply pipe 39 together.

EFFECTS OF THE INVENTION As is apparent from the above description, according to the present invention, for example, during cold start of the engine, the intake air in the intake volume chamber is positively and efficiently provided by the cooling water that reciprocates in the bypass pipe and the cooling water supply pipe. The temperature of the intake air supplied to the engine rises rapidly because the intake air is heated and is sufficiently heated in the intake volume chamber since the residence time of intake air is long. As a result, the ignitability of the mixed fuel is improved, and the output of the engine can be improved.

Moreover, since the cooling water supply pipe and the bypass pipe are simply arranged side by side along the longitudinal direction near the intake volume chamber, the piping structure is simplified, manufacturing and assembling work are facilitated, and the cost is increased. Can be suppressed sufficiently.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a water cooling type cooling device according to the present invention, FIG. 2 is a sectional view taken along the line II-II of FIG. 1, and FIG. 3 is a four-cylinder gasoline to which this embodiment is applied. It is a perspective view which decomposes | disassembles and shows the intake system of an engine. 1 ... Internal combustion engine, 3 ... Cylinder block, 5 ... Cylinder head, 8 ... Intake volume chamber, 11 ... Thermostat valve, 39 ... Cooling water supply pipe, 40 ... Bypass pipe.

Claims (1)

[Claims] 1. An intake volume chamber is provided on a side portion of an engine body along the longitudinal direction of the engine, and cooling water discharged from one end side of the engine body is introduced into a thermostat valve provided at the other end side of the engine body. A bypass pipe arranged close to the intake volume chamber along the longitudinal direction of the intake volume chamber, and a cooling water supply pipe for returning the cooling water flowing out from the thermostat valve to one end side of the engine body, in parallel with the bypass pipe. A water-cooled cooling device for an internal combustion engine, characterized in that it is arranged close to the intake volume chamber.