JPH0219294B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to startup control of an air conditioning system using a gas engine.

A conventional control device for an air conditioning system using a gas engine will be described with reference to FIGS. 1 to 4.

First, the configuration of a conventional system will be explained with reference to FIG.

A compressor 2 included in an air conditioning system 1 having a refrigeration cycle (not shown) is coupled to a gas engine 3, and the compressor 2 is rotated by rotating the gas engine 3. A solenoid valve 4 that controls the supply of gas by opening and closing is connected to the gas engine 3. The solenoid valve 4 is opened to supply gas to the gas engine 3, and the starter motor 5 is rotated to ignite the gas.
It has a mechanism for starting it. Starter motor 5
A centrifugal clutch 6 is connected to the starter motor 5, and when the gas engine 3 is started and the rotational speed increases, the starter motor 5 is automatically disconnected. Further, the gas engine 3 is provided with a shaft rotation detection means 7,
This signal is supplied to the engine governor 10, and when the rotation exceeds a certain level, the contact 10' is switched from closed to open, and the supply of power to the starter motor 5 is stopped.
The above is an overview of startup.

If the started gas engine 3 supplies gas,
Continue to rotate. The gas engine 3 will stop naturally by closing the solenoid valve 4 and cutting off the gas supply.

Figure 2 shows a conventional electrical system diagram.

Power is supplied to the system when the system power switch 8 is closed. 9 is the starter motor 5
Switch to turn on, 10' is engine governor 1
0 output contact, ON at low speed, gas engine 3
When the motor starts and reaches a high rotation speed, it is turned off and the starter motor 5 is stopped. 11 is a contact point that turns the solenoid valve coil 4' ON and OFF. 13,12
are a starting failure indicator lamp and its current-carrying contact, respectively.

The startup method for this type of system usually takes sufficient consideration to safety measures from the viewpoint of using gas, and an example of its operation pattern is shown in FIG.

As the starting mode of the gas engine 3, the starting operation is performed up to three times. FIG. 3 shows an example in which starting failed three times, and both the starting and stopping operations are set to about several seconds. At startup, the starter motor 5 and the gas solenoid valve 4 are turned on at the same time. In this case, the engine cannot be started due to some problem such as combustion conditions, and as a result, the output of the shaft rotation detection means 7 does not rise to the set value, and the engine governor contact 1
0' remains ON, and after three startup operations, the startup failure indicator lamp 13 is only turned on, and the system is brought to a halt.

Next, FIG. 4 shows an example of successful startup.

The first startup operation fails, and in this case, the startup is successful at the second time.

Starter motor 5 and gas solenoid valve 4 at the same time
As a result of the startup operation being performed with ON, the gas is ignited and the rotational speed of the engine 3 increases. During this time,
The starter motor 5 is disconnected from the engine 3 by a centrifugal clutch 6. When the output signal from the shaft rotation detection means 7 exceeds the set value, the engine governor 10 is activated, its contact 10' is turned OFF, and the starter motor 5 is stopped. On the other hand, by sending the output of the engine governor 10 to the system control section, the system recognizes that the startup is OK and starts system operation. At this time, the gas electromagnetic valve 4 remains open, and the engine continues to rotate. Naturally, the starting failure indicator lamp 13 is not lit.

The above is an overview of the operation of the conventional example. However, in the unlikely event that a startup failure occurs and the startup operation after resetting the system power is repeated, or the fuel mixture is too rich, startup may not only be difficult, but may also occur. Gas fills the engine, and in some cases, this raw gas may leak into the air via the exhaust system, which is extremely dangerous.

The present invention has been devised in view of the above, and aims to solve all of the above drawbacks.

A control device for an air conditioning system using a gas engine in an embodiment of the present invention will be explained with reference to FIGS. 5 and 6. FIG. Note that the air conditioning system in this embodiment is the same as the conventional example shown in FIG. 1, so illustration is omitted, and the same members are designated by the same numbers and detailed explanations are omitted.

In this embodiment, the process of performing the startup operation is performed in the third stage.
Although this is the same as the conventional example shown in FIG. 4 and FIG. 4, the process especially when the startup operation ends in failure is different from the conventional example shown in FIG. That is, in this embodiment, after the startup operation fails three times, the startup failure indicator lamp 13 is turned on, and at the same time, only the starter motor 5 is turned for a certain period of time, and then the system power switch 8 is opened to bring the entire system to a halt state. . As a result, the raw gas that has filled the engine due to a startup failure is released into the outside air through the engine's exhaust system, and the raw gas inside the engine is expelled as much as possible. Note that the time it takes to rotate only the starter motor 5 is approximately several seconds.

Further, in this embodiment, when the engine 3 is not driven, the starter motor contact 9 in FIG. 5 is kept closed and the starter motor 5 is
continues to drive, and after a certain period of time, contact 1
2 is closed, the system power switch 8 is opened, the startup failure lamp 13 is turned on, and the operation of the entire air conditioning system is stopped.

As is clear from the description of the embodiments above, the control device for an air conditioning system using a gas engine according to the present invention includes a gas engine that uses gas as fuel, a solenoid valve that connects and disconnects supply gas, and a centrifugal clutch. A starter motor for starting the gas engine, a detection function for detecting shaft rotation of the gas engine, an engine governor for cutting off power to the starter motor when the shaft rotation of the gas engine exceeds a certain value, and the gas engine. An air conditioning system using a gas engine is formed from a compressor, etc. that is connected to the output shaft of the engine and forms part of the refrigeration cycle, and if the gas engine does not start after repeated startup operations multiple times, an abnormality may occur. The air conditioning system includes means for displaying a state and for stopping the air conditioning system, and means for driving the starter motor for a predetermined period of time after performing a starting operation.

Therefore, according to the present invention, since a step of expelling the raw gas is included every time the starting operation is failed, it is possible to avoid a situation in which the air-fuel mixture becomes abnormally rich, smoother starting is achieved, and the raw gas is removed due to repeated starting operations. Since it is possible to avoid release into the outside air and no raw gas remains in the engine system, it has extremely high safety and other excellent effects. Moreover, this type of air conditioning system is usually installed in a room different from the room being air conditioned, so it is easy to start up, and it is not necessary to provide a means to notify abnormal conditions and shut down the system. This is extremely reliable for users who cannot directly confirm the starting status of the gas engine by sound or vibration.

[Brief explanation of drawings]

Figure 1 is a schematic configuration diagram of a conventional air conditioning system using a gas engine, Figure 2 is a control circuit diagram of the air conditioning system, Figure 3 is a timing chart when the air conditioning system has a startup failure, and Figure 4 is A timing chart when the startup is successful, FIG. 5 is a control circuit diagram of an air conditioning system using a gas engine in one embodiment of the present invention, and FIG. 6 is a timing chart showing a startup failure when using the same control device for the air conditioning system using a gas engine. This is a timing chart. 1...Air conditioning system, 2...Compressor, 3...
...Gas engine, 5...Starter motor, 8...
System power switch, 13...Start failure indicator lamp.

Claims (1)

[Claims] 1. A gas engine that uses gas as fuel, a solenoid valve that connects and disconnects the supplied gas, and a starter motor that is used to start the gas engine that is equipped with a centrifugal clutch;
a detection function that detects shaft rotation of the gas engine; an engine governor that cuts off power to the starter motor when the shaft rotation of the gas engine exceeds a certain value; An air conditioning system using a gas engine is formed from a compressor, etc. that forms part of the air conditioning system, and when the starting operation is repeated multiple times and the gas engine does not start, a display indicating an abnormal state is displayed, and the air conditioning system A control device for an air conditioning system using a gas engine, comprising means for driving the starter motor for a certain period of time after a starting operation in addition to means for stopping the system.