JPH0755298Y2 - Cooling water passage structure for engine with water-cooled turbocharger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a cooling water circulation system provided in an engine body provided with a water-cooled turbocharger and an intake passage provided with a throttle body. The cooling water passage structure of the engine with a water-cooled turbocharger, which allows the cooling water of the above-mentioned to pass through both the water-cooled turbocharger and the throttle body.

(Prior Art) An engine mounted on a vehicle is equipped with a turbocharger that supercharges intake air by using exhaust gas in order to more effectively improve intake air filling efficiency. It is known that the turbocharger is usually connected to the exhaust gas introduction part side of the turbine housing part thereof on the downstream side of the branch exhaust passage forming part extending from the engine main body, and at the same time, the exhaust gas exhausted in the turbine housing part. The exhaust passage forming portion for leading out the exhaust gas from the turbine to the outside is configured to extend from the portion side. In such a turbocharger, since the bearing portion supporting the connecting shaft that connects the turbine and the blower is exposed to high-temperature exhaust gas on the turbine side during operation of the turbocharger, for example, JP
As also disclosed in JP-A-53-68309, the cooling water discharged from the water pump in the cooling water circulation system provided in the engine body is also supplied to the bearing portion supporting the connecting shaft to cool the bearing portion. It is considered to be a water-cooled turbocharger.

In an engine mounted on a vehicle, a throttle valve provided in an intake passage forms a throttle body portion including the throttle valve, and the throttle body portion is interposed in the intake passage. It is known that the throttle body is equipped with an idling speed control valve that performs operation control according to the cooling water temperature and a fast idle mechanism to control the speed and idling speed when the engine is started. It has been proposed that the cooling water discharged from the water pump in the cooling water circulation system provided in the engine body be supplied to the throttle body as well.

(Problems to be solved by the invention) With the water-cooled turbocharger attached as described above,
In an engine provided with a throttle body part in which an idle speed control valve and a fast idle mechanism are arranged, the water-cooled turbocharger is usually positioned on the lower side of the engine body, and the throttle body part is It is supposed to be located near the intake manifold arranged in the upper part of the engine body. Each of the water-cooled turbocharger and the throttle body and the cooling water circulation system provided in the engine body are connected by a cooling water passage, and cooling water discharged from a water pump provided in the cooling water circulation system is It is supplied from the cooling water circulation system to the idle speed control valve and the fast idle mechanism arranged in the bearing portion and the throttle body portion provided in the water-cooled turbocharger through the cooling water passage. The cooling water discharged from the idle speed control valve and the fast idle mechanism arranged in the bearing portion and throttle body portion provided in the water-cooled turbocharger is, for example, a cooling water circulation system and a water-cooled turbocharger. In order to improve the circulation of the cooling water between the throttle body and the throttle body, the cooling water is guided to the suction side of the water pump in the circulation system.

However, in the cooling water, for example, when the engine is made to shift from the high rotation operating state to the idling operating state, etc., due to the decrease in the flow rate at that time,
There is a risk that bubbles will be generated that will reduce the cooling performance, and the risk is that the cooling water supplied to the bearing portion of the water-cooled turbocharger is heated by the high-temperature exhaust gas. Is made great in. Therefore, the cooling water discharged from the idle speed control valve and the fast idle mechanism arranged in the bearing portion and the throttle body portion provided in the water-cooled turbocharger is guided to the suction side of the water pump in the cooling water circulation system. When it is done, at the position on the upstream side of the water pump in the cooling water circulation system,
Both the one end of the cooling water passage from the water-cooled turbocharger and the one end of the cooling water passage from the throttle body will be connected. The air bubbles generated in the cooling water penetrate into the cooling water passage that connects the throttle body and the upstream position of the water pump in the cooling water circulation system, and as a result, the idle speed of the throttle body is reduced. There is a risk that the operation of the control valve and the fast idle mechanism may be hindered. Also, when there is a portion formed by a rubber hose or the like instead of a steel pipe in the cooling water passage that connects the throttle body portion and the upstream side position of the water pump in the cooling water circulation system, it is caused by bubbles. There is also a problem that the generated abnormal noise leaks outside through the portion formed by the rubber hose or the like.

In view of such a point, the present invention provides a water pump in a cooling water circulation system provided in an engine body having a water cooling turbocharger and an intake passage provided with a throttle body, the water pump being provided in the engine body. The cooling water discharged from the cooling water circulation supercharger and the throttle body are supplied to the cooling water circulation system, and the cooling water discharged from them is guided to the suction side of the water pump in the cooling water circulation system. The circulation of the cooling water between the turbocharger and the throttle body can be made good, and even when bubbles are generated in the cooling water discharged from the water-cooled turbocharger, the bubbles will cause A cooling water passage for a water-cooled turbocharger engine designed to prevent entry into the cooling water passage connected to the body An object of the present invention is to provide an elephant.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the cooling water passage structure of the engine with a water-cooled turbocharger according to the present invention is equipped with a water-cooled turbocharger and has a throttle body part. A cooling water supply passage portion for supplying cooling water discharged from a water pump in a cooling water circulation system provided in an engine body having an provided intake passage to a water cooling turbocharger and a throttle body, and a water cooling turbocharging In order to guide the cooling water discharged from the machine to the suction side of the water pump in the cooling water circulation system, the first cooling water return passage section having one end connected to the cooling water circulation system and the cooling water discharged from the throttle body section. A second cooling water return passage portion, one end of which is connected to the cooling water circulation system, for introducing the cooling water circulation system to the suction side of the water pump in the cooling water circulation system. The connection of one end of the return water return passage portion to the cooling water circulation system is made at a position that is upstream and below the connection of the one end of the first cooling water return passage portion and the cooling water circulation system in the cooling water circulation system. It is constructed and configured.

(Operation) In the cooling water passage structure of the engine with a water-cooled turbocharger according to the present invention configured as described above, the cooling water discharged from the first cooling water return passage portion through the water-cooled turbocharger. , And each of the cooling water discharged from the second cooling water return passage through the throttle body is guided to the suction side of the water pump in the cooling water circulation system, whereby the cooling water circulation system and the water cooling turbocharger are supercharged. Good circulation of cooling water between the machine and the throttle body.
Further, the introduction position of the cooling water discharged from the second cooling water return passage portion in the cooling water circulation system through the throttle body portion is discharged from the water cooling turbocharger discharged from the first cooling water return passage portion. Even if bubbles are generated in the cooling water discharged from the water-cooled turbocharger through the first cooling water return passage portion, by making the upstream side and the lower side of the cooling water introduction position Invasion of the second cooling water return passage portion from the throttle body portion is prevented.

(Embodiment) FIGS. 1 and 2 show a rotary piston engine for a vehicle to which an example of a cooling water passage structure of an engine with a water-cooled turbocharger according to the present invention is applied.

In FIGS. 1 and 2, an engine main body 3 supported and arranged by a plurality of mount members in an engine room 2 opened and closed by a hood panel 1 is arranged side by side in a housing 4 along a longitudinal direction of a vehicle body. And has two rotors that perform planetary rotational movement around an eccentric axis E extending in the vehicle front-rear direction, an oil pan 6 is provided below the rotor, and an intake manifold 9 is provided above the rotor. It is distributed. A cooling fan 8 is arranged at the end of the eccentric shaft E located on the front side of the vehicle body.

Branch intake passages 9a to 9d are formed in the intake manifold 9, and the branch intake passages 9a and 9b are provided in the housing 4 so as to correspond to the working chamber in which one of the two rotors is provided. The two branch intake passages 9c and 9d are connected to the two intake ports, and the two branch intake passages 9c and 9d are provided in the housing 4 so as to correspond to the working chamber in which the other of the two rotors is provided. Is connected to the intake port of.
The upstream end of the intake manifold 9 is connected to the downstream end of the throttle body 13. The throttle body 13 has a plurality of intakes whose effective opening areas are changed by throttle valves. A passage is provided, and at its lower end, an idle speed control valve 14A for performing operation control according to the cooling water temperature is provided, and further, on one side thereof, wax pellets for performing operation according to the cooling water temperature are provided. The provided first idle mechanism 14B is provided. The downstream end of the first pressurized intake passage 10 is connected to the upstream end of the throttle body 13.

An exhaust manifold 15 is arranged on the side of the housing 4 opposite to the side on which the throttle body portion 13 is located. Two branch exhaust passages are formed in the exhaust manifold 15, and one upstream end of the branch exhaust passage is
One of the two rotors is connected to the exhaust port provided in the housing 4 so as to correspond to the working chamber in which the other one of the two rotors has the other end of the two rotors. It corresponds to the working chamber provided and is connected to the exhaust port provided in the housing 4. Further, one downstream end of one of the two branch exhaust passages in the exhaust manifold 15 is connected to a turbine chamber 20a formed in the casing of the primary turbocharger 20 via an exhaust introduction part, The turbine chamber formed in the casing of the secondary turbocharger 21 whose other downstream end is located rearward of the primary turbocharger 20 in the vehicle body and juxtaposed with the engine. It is connected to 21a through an exhaust gas introducing portion.

Sequential control is performed on the primary and secondary turbochargers 20 and 21, and the primary turbocharger 20 has its turbine regardless of its operating state when the engine is operating. The exhaust gas is introduced into the chamber 20a through one of the branch exhaust passages formed in the exhaust manifold 15 and the exhaust introduction portion, whereby the turbine chamber is formed.
The turbine in 20a is driven to be in an operating state, and when the secondary side turbocharger 21 has a specific operating state of the engine, for example, when the rotation speed is equal to or higher than a predetermined value, or The rotation speed has not reached the predetermined value, but when the intake air amount is equal to or higher than the predetermined value, the turbine chamber 21a
Further, the exhaust gas is introduced through the other of the branched exhaust passages formed in the exhaust manifold 15 and the exhaust introduction portion, whereby the turbine in the turbine chamber 21a is driven and put into an operating state.

The casings of the primary and secondary turbochargers 20 and 21 have compressor chambers 20b and 2 for accommodating blowers, respectively.
1b is also formed, the intake introduction portion 22 provided in the compressor chamber 20b of the primary turbocharger 20 is connected to the branch downstream side portion 25a of the main intake passage 25, and the secondary turbocharger is also provided. The intake introduction portion 23 provided in the compressor chamber 20b of the feeder 21 is a branch downstream side portion of the main intake passage 25.
It is connected to 25b. The upstream side portion of the main intake passage 25 is connected to the air filter 26. Turbine chamber 20a and compressor chamber 20b of the primary turbocharger 20
Is connected via a connecting shaft chamber 20c through which a connecting shaft that connects the turbine and the blower is supported, and is connected to the turbine chamber of the secondary turbocharger 21.
21a and the compressor chamber 21b are connected to each other through a connecting shaft chamber 21c which is supported by a bearing portion and through which a connecting shaft which connects the turbine and the blower penetrates.

Further, the pressurized intake air delivery portion 27 provided in the compressor chamber 20b and the pressurized intake air delivery portion 28 provided in the compressor chamber 21b are respectively provided in the branch upstream side portions 30a and 30b of the second pressurized intake passage 30. The downstream end of the second pressurized intake passage 30 is connected to the upstream end of the first pressurized intake passage 10 via an intercooler 29 provided on the front side of the vehicle body. It is connected. On the other hand, the exhaust gas delivery portion provided in the turbine chamber 20a of the primary turbocharger 20 and the exhaust gas delivery portion provided in the turbine chamber 21a of the secondary turbocharger 21 are connected to each other to form an exhaust passage. Connected to 33.

A radiator 34 is arranged between the engine body 3 and the intercooler 29. One end of a cooling water introduction passage 35 forming the upstream side of the cooling water circulation system is connected to the lower portion of the radiator 34, and the other end of the cooling water introduction passage 35 is connected to the cooling fan 8 side of the engine body 3. It is arranged in a casing 36 attached to the side surface on which it is located and is connected to the cooling water inlet of a water pump driven by the engine. The cooling water introduced from the radiator 34 to the water pump through the cooling water introduction passage 35 is supplied to the water jacket formed in the engine body 3 to cool the engine body 3. The cooling water that has cooled the engine body 3 as described above is supplied to the upper portion of the casing 36 and the radiator 34.
It is returned to the inside of the radiator 34 through a cooling water outlet passage 60 disposed between the radiator 34 and the upper part of the radiator. Further, a cooling water outlet 32 for taking out cooling water flowing through the water jacket is formed in an upper surface portion of the engine body 3 which is located above the primary and secondary turbochargers 20 and 21. One ends of the cooling water supply passages 38 and 39 are connected to the cooling water outlet 32, respectively. The other end of the cooling water supply passage 38 is connected to the throttle body portion 13, and the cooling water from the cooling water outlet 32 through the cooling water supply passage 38 is the number of idle revolutions arranged in the throttle body portion 13. It is supplied to each of the wax pellets of the control valve 14A and the fast idle mechanism 14B.

One end of the throttle body 13 has a cooling water introduction passage 35.
The other end of the cooling water return passage 61 connected to the cooling water return passage 61 is connected, and the cooling water supplied to the idle speed control valve 14A and the fast idle mechanism 14B passes through the cooling water return passage 61 and the cooling water introduction passage 35. Will be introduced to.

On the other hand, the other end of the cooling water supply passage 39 has a branch cooling water passage 39a.
And 39b, and the branch cooling water passage 39b
Has a passage length longer than that of the branch cooling water passage 39a. The branched cooling water passage 39a extends from the cooling water supply passage 39 with the same diameter as that of the cooling water supply passage 39, is connected to the connecting shaft chamber 20c of the primary turbocharger 20, and is provided with a cooling water outlet. The cooling water is supplied from 32 through the cooling water supply passage 39 to the bearing portion that supports the connecting shaft that connects the turbine and the blower in the connecting shaft chamber 20c of the primary turbocharger 20. Thereby, the bearing portion in the coupling shaft chamber 20c is cooled. On the other hand, the branch cooling water passage 39b extends from the cooling water supply passage 39 with a passage diameter smaller than the passage diameter, and is connected to the connecting shaft chamber 21c of the secondary turbocharger 21.
The cooling water, which is connected to the cooling water outlet 32 and passes through the cooling water supply passage 39, is supplied to the bearing portion that supports the connecting shaft that connects the turbine and the blower in the connecting shaft chamber 21c. Thereby, the bearing portion in the coupling shaft chamber 21c is cooled.

Further, one end of a branch cooling water return passage 62a having a passage diameter substantially the same as the passage diameter of the branch cooling water passage 39a is connected to the connecting shaft chamber 20c of the primary turbocharger 20, Further, in the connecting shaft chamber 21c of the secondary turbocharger 21, it is located on the vehicle rear side from the branch cooling water return passage 62a,
One end of the branch cooling water return passage 62b, which has a passage diameter substantially the same as the passage diameter of the branch cooling water passage 39b and has a passage length longer than the passage length of the branch cooling water return passage 62a, is connected. The cooling water return passages 62a and 62b respectively form one end side of the common cooling water return passage 62. The other end of the common cooling water return passage 62 is a cooling water introduction passage.
35 connected to the primary and secondary turbochargers 20
The cooling water that has cooled the bearings provided in the cooling water introduction passages 21 and 21 passes through the common cooling water return passage 62 and the cooling water introduction passage 35.
Will be introduced to. The connection position of the other end of the common cooling water return passage 62 to the cooling water introduction passage 35 is the throttle body portion 13.
It is set so as to be located downstream of and above the connection position of one end of the cooling water return passage 61 with respect to the cooling water introduction passage 35. That is, one end of the cooling water return passage 61 for introducing the cooling water discharged from the throttle body portion 13 into the cooling water introduction passage 35 is upstream of the other end of the common cooling water return passage 62 in the cooling water introduction passage 35. They are connected on the side and at the lower position.

(Effect of the Invention) As is clear from the above description, according to the cooling water passage structure of the engine with a water-cooled turbocharger according to the present invention, the water-cooled turbocharger is attached and the throttle body is provided. The cooling water discharged from the water pump in the cooling water circulation system provided in the engine body having the intake passage is supplied to the water-cooled turbocharger and the throttle body, and the cooling water discharged from them is supplied to the cooling water circulation system. When returning to the cooling water, the cooling water discharged from the water-cooled turbocharger through the first cooling water return passage portion and the cooling water discharged from the throttle body portion through the second cooling water return passage portion are respectively cooled. Since it is guided to the suction side of the water pump in the water circulation system, the circulation of cooling water between the cooling water circulation system and the water-cooled turbocharger and throttle body Good cyclicity. Further, the introduction position of the cooling water introduced from the throttle body part to the cooling water circulation system through the second cooling water return passage part is introduced from the water cooling turbocharger to the cooling water circulation system through the first cooling water return passage part. In the case where bubbles are generated in the cooling water discharged from the water cooling turbocharger through the first cooling water return passage section by being positioned on the upstream side and the lower side of the cooling water circulation system from the introduction position of the cooling water. Also, the air bubbles are prevented from invading the second cooling water return passage portion from the throttle body portion, and the idle speed control valve arranged in the throttle body for performing operation control according to the cooling water temperature is provided. And a situation in which the operation of the fast idle mechanism or the like is hindered is avoided, and further, the second cooling water return passage is formed by, for example, a rubber hose instead of a steel pipe. Even if there is a partial or the like, a problem that leak outside it through portions abnormal noise is formed by the rubber hose or the like caused by the bubbles is eliminated.

[Brief description of drawings]

1 and 2 are a side view and a plan view showing an example of a cooling water passage structure of a cooling turbocharged engine according to the present invention together with a rotary piston engine for a vehicle to which the cooling water passage structure is applied. In the figure, 3 is the engine body, 13 is the throttle body, and 20
Is a primary turbocharger, 21 is a secondary turbocharger, 32 is a cooling water outlet, 34 is a radiator, 35 is a cooling water introduction passage,
38 and 39 are cooling water supply passages, 61 is a cooling water return passage, 62 is a common cooling water return passage, and 62a and 62b are branched cooling water return passages.

Claims (1)

[Scope of utility model registration request] 1. A water-cooled turbocharger is attached, and
A cooling water supply passage portion that supplies cooling water discharged from a water pump in a cooling water circulation system provided in an engine body having an intake passage provided with a throttle body portion to the water-cooled turbocharger and the throttle body portion; A first cooling water return passage portion whose one end is connected to the cooling water circulation system in order to guide the cooling water discharged from the water cooling turbocharger to the suction side of the water pump in the cooling water circulation system, In order to guide the cooling water discharged from the throttle body portion to the suction side of the water pump in the cooling water circulation system, one end thereof is connected to the cooling water circulation system and the first cooling water return connected to the cooling water circulation system. A second cooling water return passage portion connected at a position upstream and downward from one end of the passage portion; Cooling water passage structure of the attached engine.