JPH037588Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a compressor that boosts the pressure of compressed air supplied from a low-pressure air source as needed.

"Conventional technology" Generally, in factories that require compressed air as a power source for equipment, compressed air generated by a low-pressure compressor with a large discharge volume is supplied to the necessary departments via piping lines. , a step-up compressor (booster) that takes in low-pressure air supplied from the piping line and further compresses it to a department that requires high-pressure (higher pressure than the piping line pressure) air.
There is a tendency to adopt air supply systems in which separate air supply systems are provided.

In other words, by covering most of the required amount of compressed air with a low-pressure compressor that generally has a high discharge volume and high efficiency, the number of installed high-pressure compressors that are less efficient and have a lower discharge volume than the low-pressure compressors, Alternatively, the discharge amount of each high-pressure compressor is made as small as possible to reduce the cost of compressed air.

``Problem that the invention seeks to solve'' By the way, from the standpoint of energy conservation, it is desirable to operate the high-pressure compressor when necessary and stop it when it is not necessary. For example, if you try to start up a boost compressor that was stopped at the end of the day the next day, the boost compressor will be operated for a certain period of time and high-pressure air will be pumped in until the internal pressure of the air tank reaches a predetermined value. The problem is that it cannot be used. In addition, general compressors have the property that the discharge amount becomes extremely small as the discharge pressure increases, so it takes a very long time from startup to ready for use, especially for high-pressure compressors. The problem is that it takes time.

This idea was proposed in view of the above circumstances.
The purpose is to reduce the time required for the boost compressor to start up.

"Means for Solving the Problems" In order to achieve the above object, the present invention provides a bypass pipe that bypasses the main body of the boost compressor and connects the air tank of the compressor to the low pressure air pipe, and A switching valve is installed in the piping.

"Function" The switching valve is operated by a control circuit to open the bypass pipe and cut off the low-pressure air pipe and the compressor main body for a certain period of time before the boost compressor main body operates. The function is to direct low-pressure compressed air to the air tank, reducing the amount of air that must be sent from the boost compressor to the air tank at startup.

"Embodiment" Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

Reference numeral 1 in the figure is a low-pressure air pipe that supplies pressurized air discharged from a low-pressure compressor (not shown). The low-pressure air pipe 1 is connected to the suction side of a compressor body 4 via a filter 2 and a pilot valve 3, and the compressor body 4 is driven by a motor 5. Also, the compressor body 4
The discharge side of is connected to a high pressure air pipe 8 via an air tank 6 and a flow rate regulating valve 7.

The pilot valve 3 switches the suction side of the compressor main body 4 to the atmosphere or to the low pressure air pipe 1, and is operated by the following switching control mechanism.

That is, the switching control mechanism
a pressure switch 9 that outputs a detection signal when the internal pressure exceeds a set value; and an electromagnetic switch that causes the internal pressure of the air tank 6 to act on the pilot valve 3 when the pressure switch 9 is operated and switched. It is composed of a valve 10 and a speed controller 11 that creates a time lag between the operation of the switching valve 10 and the switching operation of the pilot valve 3.

The reference numeral 12 is a pressure gauge that displays the internal pressure of the air tank 6, and the reference numeral 13 is a safety valve that opens the air tank 6 when the internal pressure of the air tank 6 exceeds a specified value.

Further, the boost compressor is provided with a bypass path 14 (a portion surrounded by a chain line in FIG. 1) in parallel, which directly connects the air tank 6 to the low-pressure air pipe 1. This bypass path 14 is a bypass pipe 1 that connects the low pressure air pipe 1 and the high pressure air pipe 8.
5, there is an electromagnetic switching valve 16 that opens and closes the bypass pipe 15, and a low pressure air pipe 1 from the air tank 6.
a check valve 17 that prevents backflow to the air, and a pressure switch 18 that switches when it detects that the internal pressure of the bypass piping 15 (the internal pressure of the air tank 6) has exceeded a predetermined value (the internal pressure of the low-pressure air piping 1). It is composed of.

Next, the configuration of the circuit for controlling the bypass path 14 will be explained along with its operation with reference to FIG.

When a main switch (not shown) is turned on to start the boost compressor, the timer 19 is energized and activated, and its a contact 19a becomes "closed". Then, the b contact 18b of the pressure switch 18 is "closed".
(the internal pressure of the bypass piping 15 is lower than the internal pressure of the low-pressure air piping 1), the electromagnetic switching valve 16 is switched to the open state, and air is transferred from the low-pressure air piping 1 via the bypass piping 15. Compressed air is sent into the tank 6.

Next, when the set time of the timer 19 has elapsed (e.g., the time sufficient to make the air tank 6 equal to the pressure of the low-pressure air pipe 1 by causing compressed air to flow in due to the pressure of the low-pressure air pipe 1), the timer 19 is cut off and the timer 19 is turned off. b
The contact 19b becomes "closed". In addition, the pressure switch 9 is configured so that the internal pressure of the air tank 6 is low pressure air piping 1.
Switching occurs when the pressure becomes equal to that of the a contact 9.
a becomes "closed". In this state, motor 5
When the starting push button 20 is operated, the electromagnetic contactor 21 is closed, the motor 5 is operated, the boost compressor 4 is operated, and the electromagnetic valve 10 is switched. Then, by switching the solenoid valve 10, the internal pressure of the air tank 6 is applied to the pilot valve 3 via the speed controller 11 after a certain time delay from the switching of the solenoid valve 10, and the low pressure air supply piping 1 is connected to the compressor main body 4. After startup, the compressor main body 4 starts compression operation and fills the air tank 6 with high-pressure compressed air. Therefore, even if the push button 20 is operated within the set time of the timer 19 or before the internal pressure of the air tank 6 rises to a predetermined value and the a contact 9a of the pressure switch 9 is closed, the motor 5 never starts. Incidentally, reference numeral 22 is a thermal relay, and this thermal relay 22 is connected to the motor 5.
The heater 23 is activated by the heat generated by the heater 23 when a current exceeding a specified value flows through the power supply circuit of the motor 5, thereby opening the power supply to the motor 5.

Note that the control of the operating conditions of the compressor main body is not limited to the control by the timer of the above-mentioned embodiment. A method may be adopted in which the switch for starting the motor functions effectively on the condition that the pressure becomes equal to that of the air piping, and in this case as well, the bypass piping is left open for a certain period of time, and the boost compressor The time required for startup can be shortened.

``Effect of the invention'' As is clear from the above explanation, the present invention provides a bypass piping that connects the air tank of the boost compressor to the low pressure air piping. Since the air tank and the low-pressure air piping are directly connected, and the compressor body and the low-pressure air piping are isolated, the low-pressure compressor generally has a larger air supply capacity than the booster compressor body. After compressed air is supplied from the air piping and the empty air tank is filled with low-pressure compressed air in a short time, the booster compressor is operated to raise the pressure to a predetermined pressure. This has the effect of shortening the operating time of the booster compressor body required to fill the tank, increasing the pressure of the high-pressure air supply line in a short time, and quickly making it ready for use.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a piping diagram around the compressor, and FIG. 2 is a circuit diagram of the valve control mechanism. 1...Low pressure air piping, 3...Pilot valve, 4
... Boost compressor main body, 5 ... Motor, 6 ... Air tank, 8 ... High pressure air piping, 9 ... Pressure switch, 11 ... Speed controller, 15 ... Bypass piping, 16 ... Solenoid switching valve, 18...pressure switch, 19...timer.

Claims (1)

[Scope of utility model registration request] In a booster compressor that further compresses and discharges compressed air discharged from a low-pressure compressor and supplied to the suction side of the compressor body, there is a detour between the compressor body and the suction side of the compressor body. and a switching means for switching the destination of the air discharged from the low pressure compressor to the compressor main body or the bypass pipe, and a control means for controlling the switching means, the control means ,
Before the compressor main body is operated, the compressed air discharged from the low pressure compressor is pumped until the pressure on the discharge side of the compressor main body becomes approximately equal to the pressure of the compressed air discharged from the low pressure compressor. A boost compressor characterized in that a switching means is operated to lead the compressed air to a bypass pipe and to cut off the supply of compressed air to the suction side of the compressor main body.