JP2002038948A - Engine cooling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To precisely control engine cooling. SOLUTION: The communication of a third cooling water passage 19 with a second cooling water passage 16 is controlled by varying an inside 43 of a cylinder 42. The engine cooling control is made precise in the association of the communication and an opening/closing control of an air valve 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine cooling device.

[0002]

2. Description of the Related Art For example, as disclosed in Japanese Utility Model Laid-Open Publication No. Sho 61-122325 and Japanese Utility Model Laid-Open Publication No. Hei 6-74408, a warm-up operation of an engine is performed by supplying hot water to the engine when the engine is started. The idea of improving fuel efficiency, lowering exhaust gas, and improving heater performance is known.

[0003]

However, in the conventional engine cooling device, the hot water stored in the regenerator is simply circulated when the engine is started, and cooling according to the load of the engine is performed. There was a request to do so.

[0004] Therefore, it is a technical object of the present invention to provide an engine cooling device that can meet such a demand.

[0005]

The technical measures taken to solve the above-mentioned technical problem include, as described in the feature 1, "a cylinder head having a first cooling water passage formed therein; An engine having a cylinder block portion in which a second cooling water passage communicating with the first cooling water passage through a communication hole is formed. Cooling water discharged from a pump is provided between the first cooling water passage and the first cooling water passage. (2) A cooling water circulation mechanism that circulates through the pump through a cooling water passage and a return passage, or through a radiator by the action of a valve mechanism: provided in the engine, the first cooling water passage and the second (2) an air valve for opening the cooling water passage to the atmosphere: and a volume portion interposed between the discharge port of the pump and the second cooling water passage, wherein the volume of the volume portion is maximized when the engine is stopped. And maintaining the temperature of the cooling water in the volume portion, and adjusting the volume of the volume portion so as not to hinder the communication between the discharge port of the pump and the second cooling water passage at the time of starting the engine. At the time of load operation, the volume of the volume portion is adjusted so as to cut off the communication between the discharge port of the pump and the second cooling water passage. An engine cooling device comprising a heat storage control mechanism that adjusts the volume of the volume portion to the extent that communication with the second cooling water passage is not hindered.

[0006]

In the engine cooling device described in the feature 1, the warm-up / cooling mode of the engine can be changed according to the state of the engine, so that precise control can be performed.

[0007]

Embodiments of the present invention will be described with reference to the accompanying drawings.

In FIG. 1, an engine 10 includes a cylinder head 12 and a cylinder block 13. A first cooling water passage 14 and a second cooling water passage 16 are formed inside the cylinder head 12 and inside the cylinder block 13, respectively. Thus, the first cooling water passage 14
The second cooling water passage 16 communicates with the second cooling water passage 16 through a communication hole 18.

When the cooling water temperature is lower than a predetermined value, the cooling water discharged from the pump 21 flows through the first cooling water passage 14 and then circulates through the return passage 22 to return to the pump 21. Thus, as is well known, the return passage 22
If the temperature of the cooling water passing through the engine exceeds a predetermined value, the engine 1
When it is determined that the temperature of 0 has exceeded the predetermined value, the thermostat valve mechanism 25 is operated, and the cooling water returned to the pump 21 passes through the radiator 26 from the return passage 22. Pump 21, first cooling water passage 14, return passage 22, thermostat valve mechanism 25, and radiator 26
Constitutes the cooling water circulation mechanism 20.

From the discharge port of the pump 21, in addition to the first cooling water passage 14, a third cooling water passage 19 extends in parallel with the first cooling water passage 14. 19 is connected to the side of the cylinder 42 of the plunger pump 41 and communicates with the inside 43 of the cylinder 42. The inside 43 of the cylinder 42 is
6 is always in communication. And plunger pump 4
The first piston 44 drives a motor 45 and other actuators that output linear motion, thereby driving the cylinder 4.
2 slides inside 43 of the piston 4
When the cylinder 4 is displaced until the volume of the interior 43 of the cylinder 42 becomes substantially zero (described later), the third coolant passage 19
The communication with the cooling water passage 16 is shut off. The cylinder 42 is warmed by a heater (not shown) and / or is kept warm and stored by a heat insulating mechanism while the engine 1 is stopped as shown in FIG.

In FIG. 1, that is, when the engine 1 is stopped, the position of the cylinder 42 is displaced to a position where the volume of the interior 43 becomes maximum.

The plunger pump 41 and the motor 45 constitute a heat storage control mechanism 40.

The engine 10 is provided with an air valve 30. The air valve 30 is connected to the first cooling water passage 14.
As shown in FIG. 1, when the engine 10 is stopped, the valve is opened and the first cooling water passage 16 is opened.
The cooling water passage 14 and the second cooling water passage 16 are opened to the atmosphere. Therefore, all or a part of the cooling water is stored by gravity in the interior 43 of the cylinder 42 through the second cooling water passage 16.

When the engine 10 is started, as shown in FIG. 2, the piston 44 advances to a position where the communication between the third cooling water passage 19 and the inside 43 of the cylinder 42 is not interrupted. Moves in the direction to reduce the volume of the inside 43 of the device and stops. Thus, the hot water stored in the inside 43 of the cylinder 42 is supplied to the second cooling water passage 16. Thus, the second cooling water passage 16
Is connected to the first cooling water passage 14 through the communication hole 18, so that the hot water is also supplied to the first cooling water passage 14. At this time, since the air valve 30 is open to the atmosphere,
When the cooling water stored in the cylinder 42 is supplied into the first cooling water passage 14 and the second cooling water passage 16, the air in both passages is pushed out. Then, the air valve 30 is closed when all the air in the two passages is released. Thus, hot water is supplied to the cylinder head 12 in which the first cooling water passage 14 is formed and the cylinder block 13 in which the second cooling water passage 16 is formed, and these are quickly heated. That is, the engine 10 is quickly warmed up, so that the combustion can be stabilized early, the fuel consumption can be improved by reducing the friction of the sliding portion inside the engine 10, the exhaust gas can be purified, and the vehicle heater performance can be improved.

During low load operation of the engine 10, as shown in FIG. 3, the piston 44 moves forward and the communication between the third cooling water passage 19 and the second cooling water passage 16 is cut off. Thereby, the pump 21 is provided in the first cooling water passage 14.
Cooling water flows in from the
Cooling water circulates through the cooling water passage 14. On the other hand, the pump 21 is connected to the second cooling water passage 16 through the third cooling water passage 19.
Does not supply cooling water. Further, inflow of water from the first cooling passage 14 side to the second cooling water passage 16 through the communication hole 18 is also prevented. This is because the second cooling water passage 16 is a closed space. For this reason, in the second cooling water passage 16, the piston 44 of the plunger pump 41 moves and passes through the second cooling water passage 16 immediately before the third cooling water passage 19 and the second cooling water passage 16 are completely closed. The cooling water that has been accumulated stays. Thus, compared with the cylinder head 12 in which the first cooling water passage 14 is formed, the second cooling water passage 16
Is reduced (ie, the cylinder block 13 is not overcooled), and fuel consumption can be improved by reducing friction of the sliding portion.

When the engine 10 is operating under a high load,
As shown in FIG. 3, the piston 44 is slightly retracted from the position shown in FIG. 3 to enable the communication between the third cooling water passage 19 and the second cooling water passage 16. Thus, the cooling water is supplied to the second cooling water passage 16 through the third cooling water passage 19 and the inside 43 of the cylinder 42, and the cooling water passes through the first cooling water passage 14 through the communication hole 18. Merge with cooling water. Thus, both the cylinder head 12 where the first cooling water passage 14 is formed and the cylinder block 13 where the second cooling water passage 16 is formed are simultaneously cooled at the same level.

After the engine 10 shown in FIG. 2 is started, the engine 10 is stopped from either the low load state of the engine 10 shown in FIG. 3 or the high load state of the engine 10 shown in FIG. The state shifts to a state where the engine 10 shown in FIG. 1 is stopped.

The main components of the heat storage control mechanism 40 may be other than the plunger pump 41 as long as the communication can be controlled by the above-described variable volume.

Although the embodiments of the present invention have been described above, the present invention is not intended to be limited to the above-described embodiments.
Any device may be used as long as it is a device conforming to the gist of the present invention.

[Brief description of the drawings]

FIG. 1 is a diagram showing an operation state of an engine cooling device according to the present invention when an engine is stopped.

FIG. 2 is a diagram showing an operation state of the engine cooling device according to the present invention when the engine is started.

FIG. 3 is a diagram showing an operation state of the engine cooling device according to the present invention during low engine load operation.

FIG. 4 is a diagram showing an operation state of the engine cooling device according to the present invention during high engine load operation.

[Explanation of symbols]

 10: Engine 12: Cylinder head 13: Cylinder block 14: First cooling water passage 16: Second cooling water passage 18: Communication hole 19: Third cooling water passage 20: Cooling water circulation mechanism: Pump 22: Return passage 25: Thermostat Valve mechanism 26: Radiator 30: Air valve 40: Heat storage control mechanism 41: Plunger pump 42: Cylinder 43: Internal (variable volume) 44: Motor

Claims (1)

[Claims] 1. A cylinder head having a first cooling water passage formed therein and a cylinder block having a second cooling water passage formed therein and communicating with the first cooling water passage through a communication hole. Equipped engine: cooling water circulation in which cooling water discharged from a pump is circulated to the pump through the first cooling water passage, the second cooling water passage, and the return passage, or through a radiator by the action of a valve mechanism. Mechanism: provided on the engine, and the first mechanism is provided when the engine is stopped.
An air valve for opening the cooling water passage and the second cooling water passage to the atmosphere; and a volume interposed between a discharge port of the pump and the second cooling water passage, wherein the volume is provided when the engine is stopped. The volume of the volume is adjusted to a maximum so as not to impede communication between the discharge port of the pump and the second cooling water passage at the time of starting the engine. Adjusting the volume of the volume portion so as to cut off communication between the discharge port of the pump and the second cooling water passage during low-load operation of the engine; An engine cooling device comprising: a heat storage control mechanism that adjusts the volume of the volume portion as long as the communication between the discharge port of the second cooling water passage and the second cooling water passage is not hindered.