JPS58138297A - Gas engine drive refrigerator - Google Patents

Abstract

PURPOSE:To improve the reliability of a compressor by conducting power to a crank case heater to heat a compressor at the stoppage of an engine or a compressor, thereby exhausting the refrigerant stored in the compressor and preventing the liquid compression or the forming at the starting. CONSTITUTION:Upon closing of a contact 10a, it is started to supply the power while upon completion of the starting said contact 10a is opened to stop a startor 10. A relay 11 for a gas valve will close a contact 11a at the running of an engine 1 and a compressor 2 to open a gas valve 7 thus to feed the fuel to the engine 1. When the contact 11a is normal closed, a relay 12 for a crank case heater is cnnected while at the stoppage of the engine 1 and the compressor 2 where the power is not supplied to said relay 11, the power is supplied to said heater 8. Consequently the compressor 2 is heated to discharge the refrigerant stored in the machine to the refrigerating cycle thus to prevent the liquid cmpression or the forming at the rotation of the compressor 2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas engine-driven refrigerator in which a refrigeration cycle is constructed by driving a compressor by a gas engine that uses natural gas, propane gas, city gas, or the like as a heat source.

As a way to solve the recent severe electricity supply situation, such as the difficulty of constructing new power plants and the peak demand for electricity in the summer, we have decided to use compressor-driven refrigerators instead of conventional electric motors. Refrigerators driven by gas engines are attracting attention.

This gas engine-driven refrigerator is a device that has many advantages, such as high efficiency on a primary energy basis because there is no power generation efficiency involved, and the ability to effectively recover exhaust heat from the engine for hot water supply.

However, this gas engine refrigerator has a long operating time compared to heating/cooling operation, hot water supply operation, etc., and requires high durability, so it is particularly important to ensure the life of the compressor. However, unlike in the case of car coolers, etc., the refrigeration cycle is large compared to the capacity of the compressor, the refrigerant circuit tends to be long, and a large amount of refrigerant is required. As a result, refrigerant may stay in the compressor together with oil, resulting in liquid compression during startup, and lubricating oil running out of bearings due to forming, which can shorten the life of the compressor and cause seizure of the bearings. I was doing a lot of things.

In the case of electric compressors, etc., to prevent this, a crankcase heater is wrapped around the compressor, and when the compressor is stopped, it is normally connected to the reverse contact side of the electromagnetic switch of the electric motor. Measures are being taken such as energizing the heater. However, in the case of gas engine-driven refrigerators, there was still no good method.

The present invention has been made in view of the above problems, and its purpose is to improve the reliability of the compressor in a gas engine-driven refrigerator by effectively using the compressor crankcase heater. .

As a solution to this, the present invention provides an engine, a compressor driven by the engine, and a refrigeration cycle driven by the compressor, and a gas valve is provided in the fuel supply circuit of the engine, and a gas valve is provided in the fuel supply circuit of the engine, and the compressor is driven by the engine. A crankcase heater is provided, and an electric circuit is provided to energize the crankcase heater when the gas valve is closed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of an embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is an engine, 2 is a compressor driven by the engine 1, 3a is a condenser, 3b is a condenser fan, 4 is a pressure reducer, 5a is an evaporator, and 5b is an evaporator fan. A is a refrigeration cycle.

6 is a starter for starting engine 1, 7 is fuel supply circuit B
A gas valve 8 is provided to supply and stop fuel, and a crankcase heater 8 is wound around the engine 1 to heat the compressor 2 and expel refrigerant within the compressor 2. The crankcase heater 8 is configured to conduct electricity and heat when the gas valve 2 is closed.

That is, in FIG. 2, 9 is the main switch, 9a
9 is a main switch relay, and 9b is a contact point of the main switch relay 9a, which turns on the system by turning on the main switch 9. Reference numeral 1o denotes a starter relay, which is energized for startup by closing contact 10a, and when startup is complete, opens contact 10a to stop starter o.

11 is a gas valve relay, which connects engine 1. When the compressor 2:□ is in operation, the gas valve 7 is opened by closing the contact 11a, and fuel is supplied to the engine 1. The crankcase heater relay 12 is connected to the normally closed side of the contact 11a, and the engine 1. When the compressor 2 is stopped, the crankcase heater 8 is energized to heat the compressor 2, and the refrigerant stored in the compressor 2 is expelled to the refrigeration cycle outside the compressor 2, resulting in liquid compression when the compressor rotates twice. Forming can be prevented.

13 is the condenser fan relay, 13 is its contact, 14
is the relay for the evaporator fan, and 14a is its contact 1. When you want to rotate fans 3b and sb, contact 13a
, 14a are closed and the required fans 3b, ab are rotated.

In the embodiment of the present invention, the crankcase heater relay 12 is connected to the normally closed contact side of the contact 11a of the gas valve relay 11, but the contact of the crankcase heater 8 relay 12 is made independent for microcomputer control. Valve relay 1
The crankcase heater 8 may be energized to heat the compressor 2 when the compressor 1 is turned off.

As described above, according to the present invention, the refrigerant stored in the compressor is expelled by heating the compressor by energizing the crankcase heater while the gas valve is closed, that is, when the engine and compressor are stopped. This has the excellent effect of preventing liquid compression and foaming during startup and improving the reliability of the compressor.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a gas engine-driven refrigerator of the present invention, and FIG. 2 is an electric circuit diagram thereof. 1...Φ...Engine, 21+11...Compressor)
71-... Gas valve, 8... Crankcase heater, 11--■... Relay for gas valve, 11a...
・Fist contact, 12・e・・・Relay for gas heater, A・
... Refrigeration cycle, B ... Fuel supply circuit.

Claims (1)

[Claims] an engine, a compressor driven by the engine, and a refrigeration cycle driven by the compressor; a gas valve in the fuel supply circuit of the engine; a crankcase heater in the compressor; A gas engine-driven refrigerator provided with an electric circuit that energizes a crankcase heater when the gas valve is closed.