JPH0718336B2 - Soundproof water-cooled engine cooling system - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a cooling device for a soundproof engine used in a soundproof engine generator or the like, and more specifically, to a front side of a water-cooled engine in a soundproof case. A radiator and a radiator fan are installed, the water jacket of the engine and the radiator are circulated in a circulating manner with a hot water pipe and a cold water pipe, a ventilation inlet is opened at the rear of the soundproof case, and an exhaust port is opened at the front to open the engine. The present invention relates to a cooling device for a soundproof water-cooled engine in which a muffler is housed in a soundproof case.

[Prior art]

Conventionally, in the above cooling device, the radiator fan alone is used to cool the radiator and to ventilate the inside of the soundproof case.The outside air taken in from the ventilation inlet formed after the soundproof case is guided to the surroundings of the engine and then passed through the radiator. It was designed to be discharged to the outside of the machine through the air outlet on the front of the soundproof case.

[Problems to be Solved by the Invention]

According to the above configuration, the radiator and the radiator fan have a large heat dissipation capacity in order to ventilate the inside of the soundproof case, which is apt to be filled with hot air, with a single radiator fan and to sufficiently cool the engine by the radiator. In addition to that, it was necessary to enlarge the ventilation opening in order to improve the ventilation performance of the soundproof case, which made engine noise more likely to leak.

Further, since the radiator fan was continuously driven while the engine was operating, there was a problem that the fan driving noise and the cooling air exhaust noise were large even under no load or light load.

When the radiator fan is driven by the DC electric motor, it has been necessary to replace the motor consumable parts such as brushes within a short period of time.

There is also a problem that the warm-up time is long because the radiator fan starts cooling at the same time as the engine starts.

It is an object of the present invention to provide a cooling device for a soundproof water-cooled engine that can solve the problems found in the above-mentioned conventional devices.

[Means for Solving the Problems]

The characteristic configuration of the present invention for achieving the above-mentioned object is that the radiator fan 5 is driven by the electric motor 4 in the cooling system for the soundproof water-cooled engine described above, and the front side of the engine compartment A is provided. A ventilation fan 18 is provided at an intermediate height portion, a muffler chamber C is provided in the vicinity thereof, and the engine room A is communicated with the atmosphere through the ventilation fan 18 and the muffler chamber C,
The muffler 11 is housed in the muffler chamber C, the radiator cooling air inlet 24 is opened in the peripheral wall of the radiator chamber B, and the engine load detecting means 29 and the radiator fan drive for driving the radiator fan when the detected engine load is less than a set value. And a motor control means for automatically stopping the electric motor.

[Action]

According to the above configuration, the outside air sucked into the soundproof case from the ventilation inlet at the rear of the soundproof case is heated and becomes hot air to reach the front part of the engine room, and is guided to the muffler room by the ventilation fan, and then to the atmosphere. Is discharged.

Therefore, the ventilation fan is responsible for cooling the engine room and the muffler, and the radiator fan is responsible for cooling the radiator.

Further, during operation with a high engine load and a large amount of heat generation, the radiator fan is driven by an electric motor to perform the above cooling, or when a low load operation below a set value is reached, the electric motor is stopped via the motor control means. , Only the ventilation fan is used for cooling operation.

〔Example〕

FIG. 1 shows a vertical side surface of a soundproof engine generator to which the cooling system for a soundproof water-cooled engine according to the present invention is applied, FIG. 2 shows a vertical plane surface thereof, and FIG. 3 shows a vertical front surface of an essential part. It is shown.

In this engine generator, basically, a water-cooled engine 2 is installed in the middle of the soundproof case 1 with its cylinder head 2a facing forward, and a radiator 3 and an electric motor 4 are driven in front of the engine 2. The radiator fan 5 is installed, and the generator 6 which is belt-transmitted to the engine output shaft 2b is installed on the rear side of the engine 2.

A partition wall 7 is provided between the engine 2 and the radiator 3.
Is installed upright, and the inside of the soundproof case 1 is the engine 2 and the generator 6.
Further, a muffler chamber C partitioned by a partition wall 9 is formed in the upper part of the engine output side in the front part of the engine chamber A and is divided into an engine chamber A and a radiator chamber B housed in the fuel tank 8 and the like, and exhaust gas is exhausted there A muffler 11 that is connected to the cylinder head 2a via a pipe 10 is housed.

Further, a water pump 12 which is belt-transmitted to the engine output shaft 2b is provided on one side of the cylinder head 2a, and an intake port 13 of the water pump 12 is a lower tank of the radiator 3.
It is connected to 3a via a cold water pipe 14. A cooling water outlet 15 communicating with a water jacket (not shown) is provided on the upper surface of the engine tank case of the engine 2, and the cooling water outlet 15 and the upper tank 3b of the radiator 3 are connected by a hot water pipe 16. There is.

The input pulley 17 of the water pump 12 has a ventilation fan 18
And the upper part of the air guide housing 19 surrounding the fan 18 and the lower part of one side of the muffler chamber C are ventilated.
The hot air sucked by the ventilation fan 18 from one side of the front part of the engine room A is sent to the muffler chamber C to cool the muffler 11 and then to the outside through the exhaust port 21 formed in the upper part of the muffler chamber C. Is configured to be discharged to.

A ventilation inlet 22 is formed in the lower part of the rear side wall of the soundproof case 1 so that cold outside air is sucked in from the rear part of the engine room A, and an engine is provided in the upper part of the partition wall 7 opposite to the muffler room side. A ventilation port 23 that connects the front part of the room A and the radiator chamber B is formed, and a part of the ventilation introduced from the ventilation inlet 22 and reaching the front part of the engine room A flows into the radiator chamber B through the ventilation port 23. Then, the cooling air is introduced from the cooling air inlet 24 formed in a part of the peripheral wall of the radiator chamber B, passes through the radiator 3, and is discharged to the outside through the exhaust port 25 on the front side wall of the soundproof case 1.

In the figure, reference numeral 26 is an intake pipe connected to an air cleaner (not shown), and 27 is a battery.

An exhaust temperature sensor 30 as an example of engine load detection means 29 is attached to the exhaust manifold connected to the cylinder head 2a, and an electric motor for driving a radiator fan is based on a detection signal from the exhaust temperature sensor 30. 4 is configured to be on / off controlled.

That is, as shown in the block of FIG. 5, the signal from the exhaust gas temperature sensor 30 is compared with the signal from the reference temperature setter 31 in the comparison / discrimination circuit 32, and when the detected temperature θ becomes equal to or lower than the set temperature θo, The electric motor 4 is stopped via the drive circuit 33. FIG. 6 is a time chart of the above control operation.

As the engine load detecting means 29, in addition to detecting the exhaust temperature, a means for detecting the engine load from the engine speed and the control rack position of the fuel injection pump,
When a working machine such as a generator is connected as in the embodiment, it is possible to determine the engine load by detecting ON / OFF of an external load applied to the working machine.

〔The invention's effect〕

As described above, according to the present invention, the following effects can be obtained.

(1) The muffler is housed in a soundproof case, and the overall outer shape is compact, while the soundproof case is strongly ventilated by a radiator fan and a ventilation fan to prevent hot air from being trapped. The ventilation opening provided in the soundproof case can be made smaller than in the case of performing the above, so that the leakage of engine noise from the ventilation opening can be reduced and the soundproof performance can be improved.

(2) The radiator and the radiator fan do not have to bear the hot air and muffler exhaust heat in the engine compartment, and thus the heat radiation capacity is smaller, which is advantageous for downsizing.

(3) Since the electric motor for driving the radiator fan is automatically stopped when the engine is operating under no load or light load, the radiator fan driving noise and the exhaust air noise can be reduced.

(4) Since the operating time of the electric motor for driving the radiator fan becomes shorter than the operating time of the engine, the replacement period of the consumable parts of the electric motor becomes longer and the maintainability is improved.

(5) Since the radiator fan does not perform supercooling when the engine is started in the cold state, the warm-up operation time can be shortened.

(6) Since the on / off control of the electric motor for driving the radiator fan is performed based on the detection of the engine load, compared with the case where the control is performed based on the detection of the engine temperature or the engine cooling water temperature, the engine temperature or the cooling water is controlled. There is no time delay required for temperature change, the electric motor can be turned on / off with high response accuracy, and the radiator fan can be turned on / off at an appropriate timing.

[Brief description of drawings]

The drawings show an embodiment of a cooling device for a soundproof water-cooled engine according to the present invention. FIG. 1 is a vertical sectional side view of a soundproof engine generator, FIG. 2 is a cross-sectional plan view thereof, and FIG. FIG. 4 is a schematic vertical perspective view, FIG. 4 is a schematic perspective view of the whole, FIG. 5 is a control block diagram of an electric motor for driving a radiator fan, and FIG. 6 is a time chart of control operation of the electric motor. 1 ... Soundproof case, 2 ... Water-cooled engine, 3 ... Radiator, 4 ... Electric motor, 5 ... Radiator fan, 11
…… Muffler, 14 …… Cold water pipe, 16 …… Hot water pipe, 18 …… Ventilation fan, 22 …… Ventilation inlet, 24 …… Cooling air inlet, 25 …… Exhaust outlet, 29 …… Engine load detection means, A ...... Engine room, B ... Radiator room, C ... Muffler room.

Claims (1)

[Claims] 1. A radiator 3 and a radiator fan 5 are arranged in front of a water-cooled engine 2 in a soundproof case 1, and a water jacket of the engine 2 and the radiator 3 are connected to a hot water pipe.
16 and the cold water pipe 14 are connected in a circulating manner, the ventilation inlet 22 is opened in the rear part of the soundproof case 1, and the exhaust port 25 is opened in the front part.
In a cooling system for a soundproof water-cooled engine in which the muffler 11 is housed in the soundproof case 1, the radiator fan 5 is configured to be driven by the electric motor 4, and the intermediate height of the front side of the engine room A is increased. A ventilating fan 18 is provided in the lower part, and a muffler chamber C is provided in the vicinity thereof, the engine room A is communicated with the atmosphere through the ventilating fan 18 and the muffler chamber C, the muffler 11 is accommodated in the muffler chamber C, and the radiator chamber B The radiator cooling air inlet 24 is opened on the peripheral wall of the engine, and the engine load detection means 29 and the motor control means for automatically stopping the electric motor for driving the radiator fan when the detected engine load is equal to or less than the set value. A cooling system for a soundproof water-cooled engine characterized by being equipped.