JPH08254371A - Engine-driven air conditioner - Google Patents

Abstract

PURPOSE: To prevent the quality of engine oil from deteriorating, and to facilitate engine starting, by restraining a temperature drop of the engine oil during engine stopping. CONSTITUTION: A heating means 20 consisting of an electric heater 20 or the like is attached to an oil tank 1A for an engine 1 or to an oil sub-tank 17 connectively communicating with the oil tank 1A. When a temperature detected by a temperature sensor 23 is lowered at a specified value or lower, the electric heater 20 is energized by a command from a controller 24 and by heating engine oil, the temperature of the engine oil is prevented from lowering.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine driven air conditioner having a compressor driven by an engine.

[0002]

2. Description of the Related Art In a conventional engine-driven air conditioner, when the operation is started in the early morning of winter, the temperature of the engine oil decreases and its viscosity increases, so that the engine is started. However, as a result, a large amount of current flows through the starter motor, which not only shortens the service life of the starter motor but also may cause the engine to fail to start.

Further, the engine is warmed up after starting until the engine oil temperature rises to an appropriate temperature, but there is a problem that this warming up requires a long time.

[0004]

The present invention has been invented to solve the above-mentioned problems, and the gist of the first invention is to provide a compressor driven by an engine and an outdoor heat exchanger. In an engine-driven air conditioner equipped with a refrigeration cycle consisting of a throttle mechanism, an indoor heat exchanger, etc.,
A heating means is attached to the oil tank of the engine or a sub-oil tank connected to the engine and a heating control means for activating the heating means when the temperature of the oil tank or the engine oil drops below a predetermined value. The air conditioner is driven by an engine.

The heating means can be composed of an electric heater.

The gist of the second invention is that a compressor driven by an engine, an outdoor heat exchanger, a throttle mechanism,
In an engine-driven air conditioner including a refrigeration cycle including an indoor heat exchanger and the like, exhaust gas branched from an exhaust pipe of the engine flows into an oil tank of the engine or a sub oil tank connected to communicate with the oil tank of the engine. In the engine-driven air conditioner, a heat transfer pipe is attached and a switching damper is provided to switch the exhaust gas to the heat transfer pipe side when the engine is started.

The gist of the third invention is that a compressor driven by an engine, an outdoor heat exchanger, a throttle mechanism,
In an engine-driven air conditioner equipped with a refrigeration cycle including an indoor heat exchanger, etc., the cooling water branched from the cooling water circuit of the engine flows into the oil tank of the engine or a sub oil tank connected to communicate with the oil tank. The engine-driven air conditioner is characterized in that a switching valve for switching the cooling water to the heat transfer pipe when the engine is started is provided.

[0008]

In the first aspect of the invention, the engine oil is heated by the heating means such as an electric heater when the temperature of the oil tank provided with the heating means or the temperature of the engine oil in the oil tank falls below a predetermined value.

In the second aspect of the present invention, when the engine is started, the switching damper is switched to guide the exhaust gas branched from the exhaust pipe of the engine to the heat transfer pipe attached to the oil tank or the sub oil tank to heat the engine oil. .

According to the third aspect of the present invention, when the engine is started, the switching valve is switched to guide the engine cooling water to the heat transfer pipe attached to the oil tank or the sub oil tank to heat the engine oil.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A first embodiment of the invention is shown in FIG. When the compressor 2 is driven by the engine 1 during the cooling operation, the gas refrigerant discharged from the compressor 2 enters the outdoor heat exchanger 4 via the four-way valve 3 as shown by the solid arrow, and here the outdoor fan is placed. By condensing and liquefying by radiating heat to the outside air sent by 7.

This liquid refrigerant is adiabatically expanded in the process of passing through the throttling mechanism 5, and then enters the indoor heat exchanger 6, where the indoor air sent by the indoor fan 8 is cooled and vaporized. Then, the gas refrigerant returns to the compressor 2 via the four-way valve 3.

During the heating operation, the refrigerant discharged from the compressor 2 passes through the four-way valve 3, the indoor heat exchanger 6, the throttle mechanism 5, the outdoor heat exchanger 4, and the four-way valve 3 in this order as indicated by the broken line arrow. Return to compressor 2.

Exhaust gas of the engine 1 is discharged into the atmosphere through an exhaust pipe 13, an exhaust gas heat exchanger 11 and a muffler 14 which are interposed in the exhaust pipe 13.

The cooling water whose temperature has been raised by cooling the engine 1 enters the radiator 9 where it radiates heat to the outside air sent by the outdoor fan 7 to lower the temperature. Next, in the process of passing through the heat transfer tube 12 arranged in the exhaust gas heat exchanger 11, which is energized by the cooling water circulation pump 10, the exhaust gas flowing outside the tube absorbs heat, and then returns to the engine 1.

A sub oil tank 17 is installed adjacent to the oil tank 1A of the engine 1, and engine oil after lubricating the engine 1 enters the sub oil tank 17 through the oil pipe 16 and is temporarily stored therein. Then, it returns to the oil tank 1A through the communication pipe 18.

An electric heater 20 and a temperature sensor 23 are attached to the sub oil tank 17.

When the temperature of the sub oil tank 17 detected by the temperature sensor 23 or the engine oil stored in the sub oil tank 17 is input to the controller 24, the controller 24 changes the temperature as shown in FIG. 1 (B). The detected temperature is a predetermined value a
When it drops below, it is output to the switch 22 to close it.

Then, the electric current from the power source 21 flows through the switch 22 to the electric heater 20, and the electric heater 20 heats the engine oil stored in the sub oil tank 17. When the detected temperature rises to the predetermined value b, the switch 22 is opened and the electric heater 20 is de-energized.

Thus, the temperature of the engine oil can be prevented from lowering even when the engine 1 is stopped, so that the deterioration of the engine oil can be prevented. Further, since it is possible to prevent the viscosity of the engine oil from increasing, it is possible to start the engine 1 with a comparatively small force. Therefore, it is possible to reduce the life or fail to start the engine due to an excessive starting current flowing through the starter motor. It can be prevented. In addition, sub oil tank 17
Since it is possible to prevent the temperature of the internal air from decreasing, it is possible to prevent the dew condensation of water in the air and the induction thereof.

It is also possible to energize the electric heater attached to the oil tank 1A when the temperature of the oil tank 1A and the engine oil stored therein drops below a predetermined value.

A second embodiment of the invention is shown in FIG. In this second embodiment, the exhaust pipe of the engine 1
A heat transfer pipe 30 through which exhaust gas branched from 13 flows is attached to a sub oil tank 17. It should be noted that it may be arranged in the oil tank 1A.

Therefore, when the engine 1 is started, the command from the controller 35 is input to the drive actuator 33 of the switching damper 31. Then, the actuator 33 drives the switching damper 31 to switch the switching damper 31, so that the exhaust gas of the engine 1 is branched from the exhaust pipe 13 and the gas pipe 32, the heat transfer pipe 30,
It returns to the exhaust pipe 13 via the gas pipe 32, and is discharged into the atmosphere via the muffler 14. Then, in the process of passing through the heat transfer tube 30, the engine oil outside the tube is heated.

Thus, the temperature of the engine oil rises as shown by the solid line in FIG. 3, and rises to an appropriate temperature in a short time as compared with the conventional one shown by the broken line. Therefore, the warm-up operation time of the engine 1 becomes shorter than that of the conventional one, and the capacity of the air conditioner can be exhibited early.

After the warm-up operation is completed, the switching damper 31 is switched to return to the steady state, and the exhaust gas of the engine 1 is discharged into the atmosphere through the exhaust gas heat exchanger 11 and the muffler 14.

A third embodiment of the invention is shown in FIG. In the third embodiment, a heat transfer pipe 41 through which engine cooling water flows is arranged in the oil tank 1A.
It should be noted that the sub oil tank 17 can also be arranged.

When the engine 1 is started, a command from the controller 45 is output to the actuator 46 for driving the switching valve 42, which is a three-way valve, and the actuator 46 drives the switching valve 42 to switch it as shown by the broken line. Then, the cooling water flowing out from the engine 1 is transferred from the switching valve 42 to the pipe 43 and the heat transfer pipe.
41, the pipe 43, the cooling water circulation pump 10, and the heat transfer pipe 12 of the exhaust gas heat exchanger 11 to return to the engine 1 and heat the engine oil outside the pipe in the process of flowing through the heat transfer pipe 41.

When the engine oil temperature rises to an appropriate temperature, the switching valve 42 returns to the steady state shown by the solid line, and the cooling water is transferred to the switching valve.
42, the radiator 9, the cooling water circulation pump 10, and the heat transfer pipe 12 of the exhaust gas heat exchanger 11 to return to the engine 1.

Thus, also in the third embodiment, the engine oil rises as shown by the solid line in FIG. 3 and rises to an appropriate temperature in a short time as compared with the conventional one shown by the broken line. It can be shorter than the conventional one.

[0030]

According to the first aspect of the invention, when the temperature of the oil tank provided with the heating means or the temperature of the engine oil therein falls below a predetermined value, the engine oil is heated by the heating means such as an electric heater. Even when the engine is stopped, it is possible to prevent the temperature of the engine oil from lowering. Therefore, it is possible to prevent the deterioration of the engine oil and to extend the oil replacement interval.

Further, since the viscosity of the engine oil can be prevented from increasing, the engine can be started with a small force,
Therefore, it is possible to prevent a failure in starting the engine and prevent the life of the starter motor from being shortened.

In the second aspect of the present invention, when the engine is started, the exhaust gas of the engine can be guided to the heat transfer pipe attached to the oil tank or the sub oil tank to heat the engine oil therein. As a result, the warming-up time of the engine is shortened, so that the capacity of the air conditioner can be exhibited early.

According to the third aspect of the present invention, when the engine is started, the engine cooling water can be guided to the heat transfer pipe attached to the oil tank or the sub oil tank to heat the engine oil therein. As a result, the warming-up time of the engine is shortened, so that the capacity of the air conditioner can be exhibited early.

[Brief description of drawings]

1 shows an embodiment of the present invention, (A) is a system diagram, (B)
Is the electric heater on. It is a diagram which shows the relationship between OFF and temperature.

FIG. 2 is a system diagram showing a second embodiment of the present invention.

FIG. 3 is a diagram showing a temporal change in engine oil temperature at the time of starting the engine of the second embodiment.

FIG. 4 is a system diagram showing a third embodiment of the present invention.

[Explanation of symbols]

 1 Engine 1A Oil Tank 17 Sub Oil Tank 2 Compressor 4 Outdoor Heat Exchanger 5 Throttling Mechanism 6 Indoor Heat Exchanger 9 Radiator 10 Cooling Water Circulation Pump 11 Exhaust Gas Heat Exchanger 13 Exhaust Pipe 14 Muffler 20 Electric Heater 21 Power Supply 22 Switch 23 Temperature Sensor 24 controller

Front page continuation (72) Inventor Minoru Hanai 1 Takamichi, Iwazuka-cho, Nakamura-ku, Nagoya City Mitsubishi Heavy Industries, Ltd. Nagoya Research Laboratory (72) Inventor Michio Yoneda 1 Takamichi, Iwazuka-cho, Nakamura-ku, Nagoya Mitsubishi Heavy Industries Ltd. Company Nagoya Research Laboratory (72) Inventor Tadahiro Kato 3-1, Asahi-cho, Nishibiwajima-cho, Nishikasugai-gun, Aichi Prefecture Mitsubishi Heavy Industries, Ltd. Air Conditioning Factory

Claims (4)

[Claims] 1. An engine-driven air conditioner having a refrigeration cycle including an engine-driven compressor, an outdoor heat exchanger, a throttle mechanism, an indoor heat exchanger, and the like, wherein an oil tank of the engine or a communication therewith. An engine-driven air characterized in that a heating means is attached to the connected sub-oil tank, and heating control means for activating the heating means when the temperature of the oil tank or engine oil drops below a predetermined value. Harmony machine. 2. The engine-driven air conditioner according to claim 1, wherein the heating means comprises an electric heater. 3. An engine-driven air conditioner having a refrigeration cycle including a compressor driven by an engine, an outdoor heat exchanger, a throttle mechanism, an indoor heat exchanger, etc., wherein an oil tank of the engine or a communication therewith. The sub oil tank connected is provided with a heat transfer pipe through which the exhaust gas branched from the exhaust pipe of the engine flows, and a switching damper is provided to switch the exhaust gas to the heat transfer pipe side when the engine is started. A characteristic engine-driven air conditioner. 4. An engine driven air conditioner having a refrigeration cycle including a compressor driven by an engine, an outdoor heat exchanger, a throttle mechanism, an indoor heat exchanger, etc., wherein an oil tank of the engine or a communication therewith. A heat transfer pipe through which cooling water branched from the cooling water circuit of the engine flows is attached to the connected sub oil tank, and a switching valve is provided to switch the cooling water to the heat transfer pipe when the engine is started. A characteristic engine-driven air conditioner.