FI119199B - Suction - Google Patents

Description

1 119199

IMUVENTTOLI

The invention relates to a suction vent for bridging a pipe for closing, adjusting and preventing backflow, wherein the suction valve comprises a movable shut-off member disposed in the valve housing and a counter-surface in the valve housing and the movable shutter - or cylinder part Especially the valve is suitable as a suction valve for screw and root-10 tor compressors, which causes extremely low flow loss and is adjustable and closes as required. Closing the suction valve prevents backflow from the compressor when the compressor stops.

It is known in the prior art a suction valve e.g. U.S. Patent No. 6,695,007, wherein the flow of 15 fluid keeps the valve open. As the flow decreases or, for example, the compressor suction effect decreases, a spring in the valve pulls the valve closing member against the seat surface and closes the valve. In such a spring-return valve, there is always some more pressure loss due to the flow keeping the valve closing member open. Loss of pressure occurs even if the spring has a relatively low resistance force. When larger compressors run almost 24 hours a day, even a small reduction in the efficiency of ·· ·: V due to their suction valve becomes a significant • ·: cost in producing compressed air. In addition, the spring-loaded suction valve is difficult to adjust • • · t · * * to the intermediate position close to the shut-off position to provide compressor relief. The relief must therefore be made by closing the φ · · *** | 25 valve, which is effected by the application of spring force or otherwise by moving the movable • · ***** closing member against the closing surface.

• · • ♦ · *: l: To improve the drawbacks shown and to reduce the flow loss when used with a very small::. **, a new suction valve for the fluid is developed to provide the suction valve. pressure • »· • · '···' by forming the piston or cylinders of the fluid-acting cylinder piston) Sax. The suction valve of the invention described above is characterized in that the fluid pressure required to move the closure member is introduced into said closure member via a special quick-release valve fitted into the closure member 2 119199.

An advantage of the suction valve according to the invention is that the opening of the valve does not cause 5 flow losses in the valve. The valve remains open by means of the suction pressure of the compressor, which pressure is allowed to act in the cylinder space formed by the closing member in the direction that pulls the closing member into the open position. The compressor only needs to suck the vacuum into the said space through the quick-release valve, and after that there will be no loss when the valve is opened. The quick-release valve fitted inside the suction valve closure member is controlled by the pressure of the medium supplied thereto. Closure and opening of the suction valve is controlled by the available propellant medium. The control is thus carried out independently of the operation of the compressor. The closing member is also adjustable to any intermediate space between the closing and open positions. By means of the quick release valve, the movement of the closure member from the closure to the open position is made very no-15 when the pressure of the medium which presses the closure member into the closed position is rapidly discharged through the express outlet valve into the compressor suction pipe. The suction valve causes very little flow resistance of the flow bypasses the inlet valve and the downstream formulations capable of making very streamlined.

In the following, the invention will be explained in more detail with reference to the accompanying drawing, in which: '': Figure 1 shows a valve in accordance with the invention in sectional view with the valve open.

Fig. 2 shows the valve in the closed position.

Fig. 1 shows a suction valve having an outer shell formed by two seals 6 ...: * 25 using one of the intact portions la and Ib which can be connected to one another in some known manner, such as by means of screws. The second part Ib is connected to the closure member sleeve-shaped • ·: * j · fixed part 4 by means of wings 2 guided across the annular flow channel, the outer surface of which is arranged as a sliding surface to co-operate with the • member. The parts 3 and 4 are like a cylinder and a piston which move with respect to each other. Part 3 is provided with a seal 11 and part 3 in the closing position presses ··· against the counter surface of part la as the seal 11 seals. The wing 2 connecting the portion 4 to the portion Ib *; **: is slightly thicker, whereby it has been possible to pass: ***: the channel S externally into the portion 4.

·· # 119199 3

The quick release valve is secured inside the sleeve-like part 4 by a locking ring 12. The quick release valve includes an outlet 7 which leads directly to the suction space of the compressor. Furthermore, it comprises a flange-shaped closing flange 10 in the cylindrical body of the valve 8 5 which is made of a flexible material such as polyurethane. A fixed support flange 9 is connected to the body 8. The closing flange 10 closes the outlet 7 if the pressure applied through the duct 5 and further down the duct 10 behind the closing flange 10 is higher than the pressure in the outlet 7. In the state of Figure 1, no pressure is applied to the quick-release valve 10 through duct 5. Channel S may be e.g. connected to the same pressure as the compressor suction side ie. The chamber, which outlet 7 is discharged. The closing member 3 remains in the state shown in Fig. 1 and does not seek to close. Flow losses caused by the closing member are thus minimized.

The situation of Fig. 2 can be achieved both when the compressor stops and when it is running. Through the passage 5, for example, control pressure is applied from the pressure side of the compressor to the quick-release valve behind the shut-off flange 10, whereupon it moves to block the outlet 7. The material of the shut-off . The compressor is now running light or stopping.

· * * • *, · The pressure cannot escape back from the compressor.

♦ · * * ♦ * · · * ·· *

When the suction valve is desired, it is done very quickly by the control pressure * of the duct 5: which is a very small amount of air. In this case, the cylinder member 3 a 9 · ···. The inside pressure 25 is capable of immediately pushing the shut-off flange 10 of the quick-release valve slightly to the left, whereby the pressure inside the shut-off member 3 is rapidly discharged through the outlet 7 of the starter compressor and the shut-off flange 10 remains in position. Within the shut-off member 3, a vacuum is drawn by the compressor and the shut-off member 3 * · "· 'quickly moves to the open position and the flow is able to bypass the valve. Thus, running or starting the compressor · *. **: 30 accelerates valve opening.

* »· • · • *

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*: **: Adjustable intermediate positions for the shut-off member 3 are also obtained in the position of the quick-release valve according to Fig. 2 by passing only a controlled amount of medium into the space formed inside the shut-off member 3 and part 4.

Claims (6)

119199 A piping suction valve for filing means for closing, adjusting and preventing backflow 5, the suction valve comprising a movable shut-off member (3) disposed in the valve housing (1) and an adjacent surface thereof in the valve housing and the movable shut-off member (3) by forming a closing member (3) into a piston or cylinder part of a cylinder driven by fluid pressure, characterized in that the 10 control fluid pressure required to move the closing member (3) is introduced into said closing member via an outlet valve (8, 9, 10) (3) in. Suction valve according to Claim 1, characterized in that the pressure of the guiding fluid applied to the outlet valve is adapted to close the outlet valve 15 (7), e.g. by means of a pressure-displaceable shut-off valve (10). Suction valve according to Claim 1, characterized in that the reduction of the pressure of the fluid introduced into the outlet valve is arranged to open the outlet valve (8, 9, 20 10) for a quick opening of the closing member (3). • · * · • • • • • * * The suction valve according to claim 1, characterized in that the outlet valve * ··· «• φ. (8, 9, 10) The outlet is adapted to open into the piping downstream of the suction valve, · ·, viewed in the flow direction. ·: ΊΓ 25 • · • · Suction valve according to claim 1, characterized in that the closing element (3) is; a movable cylinder adapted to be movable with respect to the sleeve-like piston (4). • · · ·· ♦ · • · · • • • e A suction valve according to claim 1, characterized in that the exhaust valve * ··· * • · t. 30 (8, 9, 10) is disposed within the sleeve-like piston (4). • • • m • · • · · »» • • • 5 119199