Pneumatic drive system and method for operating the pneumatic drive system

Patent metadata

Field	Value
Publication number	US-9500293-B2
Application number	US-201314064416-A
Country	US
Kind code	B2
Filing date	Oct 28, 2013
Priority date	Oct 31, 2012
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

In a method or device for operating a pneumatic drive system for actuating a control valve, a pneumatic working chamber is loaded with pneumatic pressure in order to move the control valve into a desired position. At least two pneumatic control signals are supplied to the working chamber by means of electropneumatic conversion.

First claim

I claim as my invention:

1. A pneumatic drive system for actuating a control valve, comprising:
a pneumatic working chamber and a current/pressure transducer coupled with the working chamber for loading the working chamber with a pneumatic pressure to move the control valve; and
the current/pressure transducer having an electrical input configured to receive an electrical control signal, the current/pressure transducer being configured to:
generate at least two pneumatic control signals with which the working chamber is loaded, the at least two pneumatic control signals including a high flow rate control signal having a high flow rate and a low flow rate control signal having a low flow rate;
supply the high flow rate control signal and the low flow rate control signal to the pneumatic working chamber simultaneously to regulate a position of the control valve;
switch off the high flow rate control signal while maintaining the low flow rate control signal in the event that at least one of a permitted vibration amplitude limit and vibration frequency limit is exceeded at the control valve.

2. The drive system according to claim 1 wherein the current/pressure transducer performs at least one of the following functions:
generates the at least two pneumatic control signals independently of one another; and
supplies the at least two pneumatic control signals to the working chamber independently of one another.

3. The drive system according to claim 1 wherein air flow rates of the at least two pneumatic control signals are pre-set.

4. The drive system according to claim 1 wherein the current/pressure transducer has a regulating electronics which regulates the generation or supply of the at least two pneumatic control signals on the basis of at least one of a received set-point control value and an actual control value, the at least two pneumatic control signals being generated by respective independent subassembly transducers operating independently of each other.

5. The drive system according to claim 4 wherein the regulating electronics has a clock generator which temporally times a loading of the working chamber with said at least two pneumatic control signals in such a manner that the at least two pneumatic control signals are supplied to the working chamber simultaneously.

6. The drive system according to claim 1 wherein the current/pressure transducer has at least two pneumatically separated pneumatic output ports which are connected to the working chamber, and wherein the at least two pneumatic control signals leave the current/pressure transducer separately from one another via the at least two pneumatically separated pneumatic output ports.

7. The drive system according to claim 1 wherein a line network with parallel lines connects to the current/pressure transducer, said parallel lines each conducting a respective one of said at least two pneumatic control signals.

8. The device of claim 1 wherein the control valve comprises a processing plant control valve.

9. A method for operating a pneumatic drive system for actuating a control valve, comprising:
loading a pneumatic working chamber with pneumatic pressure in order to move the control valve into a position; and
supplying at least two pneumatic control signals to the working chamber using electropneumatic conversion, the at least two pneumatic control signals being provided with differently sized air flow rates to regulate the position of the control valve, wherein the at least two pneumatic control signals are supplied to the working chamber simultaneously, and in the event that at least one of a permitted vibration amplitude limit and vibration frequency limit is exceeded at the control valve, one of the at least two pneumatic control signals with a high air flow rate is switched off while maintaining another of the at least two pneumatic control signals with a low air flow rate.

10. The method according to claim 9 wherein each of said at least two pneumatic control signals is generated by an individual current/pressure conversion procedure.

11. The method according to claim 9 wherein air flow rates of the at least two pneumatic control signals are preset.

12. The method according to claim 9 wherein the at least two pneumatic control signals are provided with differently sized pressure values, wherein only a high pressure control signal or high air flow rate control signal is switched on for opening or closing the control valve, or only a low pressure control signal or low air flow rate control signal is switched on for carrying out a partial stroke test.

13. The method according to claim 9 wherein the at least two pneumatic control signals have differently sized pressure values, and wherein, to displace the control valve, the at least two pneumatic control signals with differently sized pressure values are simultaneously supplied to the working chamber during a predetermined pulse period or for as long as it takes for the control valve to respond, and subsequently one of the control signals is switched off.

14. The method of claim 9 wherein the control valve comprises a processing plant control valve.

Assignees

• Valentin-Rumpel Frank
• Samson Ag

Inventors

• Valentin-Rumpel Frank

Classifications

• F16K31/1245

  with more than one valve · CPC title

• F15B2211/6653

  Pressure control · CPC title

• F15B5/006 Primary

  with electrical means, e.g. electropneumatic transducer (F15B5/003 takes precedence) · CPC title

• F15B2211/8855

  Compressible fluids, e.g. specific to pneumatics · CPC title

• F15B2211/6656

  Closed loop control, i.e. control using feedback · CPC title