RU2503868C1 - Locking device - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: locking device includes a pneumatic valve with inlet, outlet and control cavities and an electric valve. The above electric valve is located in a channel that connects inlet and control cavities. In a channel between the electric valve and the control cavity there installed is a delay valve. The latter has inlet, outlet and control passages and includes a piston pushed with a spring towards the inlet passage. The first cavity of the above delay valve is interconnected with the inlet passage to the electric valve, and the other surface is connected to the outlet cavity through the outlet passage. A check valve is installed in the above outlet passage. The control passage is interconnected with the control cavity of the pneumatic valve. In the piston there is a passage connecting the first and the second cavities to each other. A throttle is installed in the above passage. On the piston end on the side of the second cavity there is a seal made so that it can overlap the control passage when it is being mounted on the housing seat. Diameter of the seat in the housing is equal to the piston diameter.

EFFECT: excluding pneumatic impact at opening of a pneumatic valve of large cross section; simplifying the structure at designing a locking device.

1 cl, 1 dwg

Description

The invention relates to the field of pneumatic automation and can be used for remote supply of a high pressure medium to elements of gas supply systems without pneumatic shock.

To eliminate the negative impact of pneumatic shock on the main pneumatic valves from the sharp opening of the shut-off device of a large bore in gas supply systems, the parallel installation of two electro-pneumatic valves of large and small bore is used. In this case, the output line is pre-filled through a small section electro-pneumatic valve.

Known electro-pneumatic valve according to the author's certificate of the USSR No. 396511, class. F16K 11/10 (analog). It contains a pneumatic valve with inlet, outlet, and control cavities and an electrovalve in the channel or pipeline communicating the inlet and control cavities.

The disadvantages of the analogue is a sharp opening, accompanied by a pneumatic shock when filling the output connected line.

Known electro-pneumatic valve according to the author's certificate of the USSR No. 501237, class. F16K 31/02 (prototype), which contains a pneumatic valve having a valve, piston, inlet, outlet and control cavity. In the channel communicating the input and control cavities, a control electrovalve is installed.

To reduce pneumatic shock when opening in the prototype body, a check valve is provided that communicates the electrovalve and the outlet cavity.

The disadvantages of the prototype are the possibility of pneumatic shock due to its opening with a significant pressure difference between the inlet and outlet cavities and a sharp opening of the valve due to imbalance in the outlet pressure. In addition, the installation of an electrovalve and a non-return valve in the housing complicates the design of the electro-pneumatic valve with a large flow area.

A locking device is proposed that eliminates these drawbacks.

The locking device comprises a pneumatic valve with an inlet, outlet and control cavities, and an electrovalve in a channel communicating the inlet and control cavities of the pneumatic valve.

The difference between the invention and the prototype is the presence of a delay valve installed in the channel between the electrovalve and the control cavity of the pneumatic valve.

The delay valve has an inlet, outlet and drainage channels. The input channel is connected to an electrovalve. The outlet channel is connected to the outlet cavity of the pneumatic valve and a check valve is installed in it with the flow direction towards the outlet cavity. The control channel is connected to the control cavity of the pneumatic valve. The delay valve has a piston, the cavities of which are interconnected by a channel in which the throttle is installed.

The delay valve piston is single-stage and spring pressed towards the inlet channel. The output channel is located inside the seat, the control channel is located outside the seat of the housing. The diameter of the seat in the housing is equal to the diameter of the piston seal.

The technical effect of the use of the invention is to exclude a pneumatic shock when opening a large cross-section pneumatic valve, simplifying the design when performing the locking device. This allows you to prevent self-oscillation of gas gears and reduce wear of moving parts and seals of pneumatic fittings installed in the output line. Simplification of the design is provided by installing a check valve in the piston, which simplifies the passage of channels and does not increase the dimensions of the housing.

The main advantage in the industrial application of the invention is the simple refinement of existing shut-off devices with a large flow area by installing a delay valve in the pipeline between the solenoid valve and the control cavity of the pneumatic valve. This allows you to exclude a pneumatic shock in the output line.

The drawing shows the proposed locking device.

The pneumatic valve 1 has an input 2, output 3 and control 4 cavities. It has a valve 5 with a spring 6 connected to the piston 7. Between the inlet 2 and the control 4 cavities, a normally closed solenoid valve 8 and a delay valve 9 are installed. The elements are connected by pipelines 10, 11, 12, 13.

The delay valve 9 has an input 14, output 15 and control 16 channels. The input channel 14 is connected to the electrovalve 8 by a pipe 11. The output channel 15 is connected to the output cavity 3 of the pneumatic valve 1 by a pipe 12.

A check valve 17 is installed in the output channel 15, having a flow direction in the direction of the output cavity 3. The control channel 16 is connected by a pipe 13 to the control cavity 4 of the pneumatic valve 1. In the delay valves 9 there is a piston 18 having a cavity 19 from the side of the electrovalve 8 and a cavity 20 with the sides of the output channel 15. The cavities 19 and 20 are interconnected by the channel 21, in which the throttle 22 is installed.

The piston 18 of the delay valve 9 is single-stage and pressed by a spring 28 together with the seal 23 from the seat 24 towards the inlet channel 14. The output channel 15 is located outside the seat 24. The diameter of the seat 24 is equal to the diameter of the piston seal 18.

The locking device operates as follows.

In the initial position, the solenoid valve 8 is closed, the pressure is supplied to the inlet cavity 2, the valve 5 of the pneumatic valve 1 is closed. There is no pressure in the outlet cavity 3. The locking element in the output line connected to the cavity 3 is closed.

To open the pneumatic valve 1, the electric valve 8 opens. The working medium under pressure from the inlet cavity 2 through the channel 21, the throttle 22, the check valve 17 enters the outlet cavity 3. There is a smooth, shockless filling of the main connected to the outlet cavity 3 with a closed shut-off element.

The pressure drop across the throttle 22 between the inlet pressure in the cavity 19 and the outlet pressure in the cavity 20 presses the seal 23 against the seat 24, blocking the control channel 16.

As the outlet cavity 3 is smoothly filled together with the connected line, the pressure in the cavity 20 reaches a value that can overcome the effect of the inlet pressure on the piston 18 from the side of the cavity 19. In the shut-off device 9, the seal 23 is separated from the seat 24 by the combined action of pressure in the cavity 20 on the area of the piston 18 and the spring force 28.

After opening the control channel 16, the pressure from the inlet cavity 2 through the open electrovalve 8, the throttle 22 enters the control cavity 4 of the pneumatic valve 1. The valve 5 is opened and the outlet cavity 3 is refilled with the connected line to a pressure equal to the inlet.

Full opening of the pneumatic valve 1 occurs at a constant pressure drop between the inlet and outlet pressures, determined by the action of the force of the spring 28 on the area of the piston 18.

Thus, shock-free filling of the output line with the proposed locking device is provided.

To close the shut-off device, the electrovalve 8 is closed. The pressure from the control cavity 4 of the pneumatic valve 1 is drained through the open seal 23, the throttle 22 and the drainage of the electrovalve 8 into the environment, while the check valve 17 prevents the flow of gas from the outlet cavity 3 into the drainage. Valve 5 is acted upon spring 6 closes.

The advantage of the proposed invention is the ability to modify existing shut-off devices by installing the proposed delay valve in the control pipe between the solenoid valve and pneumatic valve.

The proposed technical solution has been tested experimentally and it is planned to introduce it into the design documentation of one of the products developed by the Armature Design Bureau.

Claims (1)

A locking device containing a pneumatic valve with an inlet, outlet and control cavities and an electrovalve in the channel communicating the inlet and control cavities, characterized in that a delay valve is installed in the channel between the electrovalve and the control cavity, having an inlet, outlet and control channels and containing a pressed spring in the side of the inlet channel is a piston, the first cavity of which is communicated by the inlet channel with the electrovalve, and the second cavity - with the outlet cavity by the outlet channel in which the check valve is installed, the supply channel is in communication with the control cavity of the pneumatic valve, a channel is made in the piston that communicates between the first and second cavities, a throttle is installed in the channel, there is a sealant on the end of the piston from the side of the second cavity, which is capable of overlapping the control channel when landing on the body seat, seat diameter in the housing is made equal to the diameter of the piston.