SU1211703A1 - Air supply device - Google Patents

Description

2. The device for Ti. 1 j This is due to the fact that the first cable is sealed with an electric control valve, the drive of which is connected to the power supply circuit through the normally closed contacts of the first pressure switch and through the normally open contacts of the second pressure switch.

1211703

3. The device according to claim 1, about tl and -. tea | t e f with. we say that the first choke for | The valve has a constant pressure drop.

4.Ustroys; about on nn I and 3, T - wherein the control chamber of the second pressure switch is connected to the power source via a check valve.

The invention relates to pressurized compressed air supply and can be used in pneumatic automation, preferably in installations with low air consumption.

The purpose of the invention is to reduce energy consumption (decrease in pressure of the injection-compressor and its own air flow) and the distribution of functional capabilities (working with vacuum and expanding the range of tuning the dead zone towards low pressures).

The ka of FIGS. 1-2 depicts a diagram of the proposed device, FIG. 3 is a diagram of the state of the device for stabilizing the negative pressure (vacuum).

The device contains sources)

supply - 1 water compressor, first throttle

electric second

choke 3, receiver 4, first p -.:;:,.: 5 pressure p second pressure relay 6 pressure relief valve 7, electrically operated valve 8 p pressure gauge 9 for measuring pressure in receiver 4, circuit 10 pnt1-device.

The device is as follows.

In the initial state, when the air pressure in the receiver 4 is zero, the bullet and pressure in the lower chambers of both pressure switches 5 and 6 are equal, the electrical outputs, contacts n - 5 of both relays are closed at the initial moment of power supply The power supply circuit 10 triggers the pressure relief valve 7 and the cavity of the first pressure relay 5 communicates via terminal 7 with the atmosphere. At the same time, compressor 1 starts to pump from; fresh air through the first 2 throttle 2 to receiver 4 and directly) and {0 to the control chamber of the second pressure switch 6.

From receiver 4, air flows through the second throttle, 3 into control chamber A of the first relay 5, pressure mfi. The pressure in it does not increase, as the incoming air is discharged through valve 7 to the atmosphere. As soon as the pressure at the outlet of compressor 1 (at the inlet of throttles 2) reaches the threshold of operation of the second pressure switch 6, it triggers, its electrical output - contacts a –b open, and contacts a- & closes. Ulapan 7 were ceased to stop the release of pressure and: - the control chamber of the first pressure 5 relay. At the same time, the valve 8 is also opened, because its control circuit is closed after a cycle of both relays 5 and 6 of the pressure and compressor air enters the receiver 4 minutes, choke 2 without energy rubbing.

But as pressure rises in receiver 4, it rises in the control chamber of the first pressure relay 5 (through the second choke 3). At the moment when the pressure in the receiver 4 reaches the upper threshold of the first pressure 5 relay, its contacts LS - S are broken, compressor 1

is turned off, the valve 8 is closed and the pressure in the control chamber of the second pressure switch 6 is equalized through the first throttle 2 with the pressure of the receiver 4. As it is consumed from the receiver 4, the second pressure switch 6 triggers first, followed by the valve 7.

The first pressure switch 5 switches over, turning on the compressor 1, but the valve 8 is turned on only after switching the second pressure switch 6 and switching its electrical contacts. The cycle of the installation is repeated,

FIG. 3 shows a schematic of a device for stabilizing negative pressure (vacuum). The device operates as in FIG. 1 with the only difference that compressor 1 pumps air out of the system, and pressure relays 5 and 6 are set to negative pressure (vacuum),

FIG. 2 shows a diagram of the device in one of the particular cases of execution. The air supply device additionally contains a valve 11 and a check valve 12 for a constant differential pressure.

The device according to this embodiment operates as follows. In the initial state, when the air pressure in receiver 4 is zero, the pressure in control chambers of both relays 5 and 6 of pressure is zero, the electrical contact; both relays are closed. At the initial moment of supplying power to the installation input, the pressure relief valve 7 is activated and the chamber of the first pressure relay 5 communicates via valve 7 with the atmosphere. At the same time, compressor 1 begins to pump compressed air through valve 11 into receiver 4 and the second reverse valve 12 into the control chamber of the second pressure relay 6 and through the first throttle 2 also into the receiver 4. From receiver 4, air flows through the second throttle 3 into the control chamber of the first pressure switch 5, but the pressure in it does not increase, as the incoming air is discharged through valve 7 to the atmosphere. The air pressure in the line from source 1 is quickly set to equal the pressure in receiver 4 plus pressure drop to valve 11 (this difference is determined by the spring force and the inherent resistance of the channels of the valve itself). The resistance of the check valve does not affect the pressure in line from the source, since the conductivity of the first throttle 2 is significantly less reducibility valve 11.

five

five

0

0

The pressure drop across valve 12 is selected to be minimal. The purpose of this valve is to prevent air from being released through the valve of compressor 1 during a pause in its operation. In the particular case, when there is no air leakage through the valve of an inoperative compressor 1 pet, there is no need for a reverse valve, it may be absent.

As soon as the pressure in the line, and thus in the control chamber, the second pressure relay 6 exceeds the upper threshold of the second pressure relay 6, the pressure relief valve 7 closes, the pressure in the control chamber of the first pressure relay 5 becomes equal. pressure in receiver 4 (. pressure drop on throttle 3 due to the smallness of the chamber of the relay 5 yes. plsnik (neglected), As far as polypropylene; -; receiver 4; The pressure in the chamber of the second pressure is always greater than iiii the value of the differential across valve 11,

As soon as pressure in receiver 4 exceeds the upper threshold of the first pressure switch 5, its contacts are open and compressor 1 is turned off. The pressure in the chamber of the second pressure relay and in the master: iii through the first throttle 2 is equalized with the pressure in the receiver 4,

Let the air flow out of

jyec.i- .Bepa 4 has relieved the pressure in it; a, et SJ; at the same time, the eye is reduced from both the control chambers of both relays 5 and pressure. If the dead zone of the first pressure relay 5 is zibr; within the zone of allowable pressure fluctuations in recire 4, and the lower threshold of this relay is also set below the lower threshold, n1; the second relay 6 daElevi, then r; the second pressure switch 6 switches the first pressure switch D to the receiver 4. At the moment of operation of the second pressure switch 6, the valve 7 also activates to the control chamber of the first pressure switch 5 drop abruptly to atmospheric, the relay is activated and the compressor 1 is turned on, the pressure in the line and, therefore, in the control switch of the second relay 6 pressure also rises abruptly

the upper threshold of the operation of this relay, the relay switches again and the valve 7 is closed, the air discharge through the choke 3 is stopped, and further filling of the receiver 4 to

top pressure without parasitic air loss. After the pressure rises to the upper level, the pressure relay 5 will operate and the operation cycle will repeat.

FIG 2

 entrance

FIG.

Claims (4)

1. A device for air supply, containing a power source with an electric drive connected through the first choke to the receiver; the first pressure switch with electric output, connected to the power supply circuit of the electric drive and connected through the second inductor to the receiver, and a pressure relief valve from the control chamber of the first pressure switch, characterized in that, in order to reduce energy consumption and expand the functionality, it has a second relay pressure with an electrical output included in the control circuit of the electric actuator of the pressure relief valve, and the control chamber of the second pressure switch is connected to the output of the power source. Figure 1 2. The device according to π. 1, distinguished by the fact that the first throttle is shunted by an electrically controlled valve, the actuator of which is connected to the power circuit through the normally closed contacts of the first pressure switch and through the normally open contacts of the second pressure switch. 3. The device according to claim 1, with the proviso that the first throttle is shunted by a constant differential pressure valve. 4. The device for pi. 1 and 3, characterized in that the control chamber of the second pressure switch is connected to the power source through a check valve.