Positioner methods and apparatus

• US 3,906,726 A
• Filed: 12/20/1974
• Issued: 09/23/1975
• Est. Priority Date: 12/20/1974
• Status: Expired due to Term

• Current Assignee: Varco International Inc. (NOV, Inc.)
• Original Assignee: Douglas L. Jameson
• Inventors: Jameson, Douglas L.
• Primary Examiner(s): Geoghegan, Edgar W.
• Application Number:
  US05/534,848
• Time in Patent Office: 277 Days
• Field of Search: 60/327,413,387,386,398 91/1R,391R 175/24,40 137/236
• US Class Current: 60/327
• CPC Class Codes: F15B 1/04 Accumulators
• CPC Class Codes: Y10T 137/402 Distribution systems involving geographic features

Abstract

This invention relates to methods and apparatus for controlling the positioning of a device such as a fluid control valve. Hydraulic cylinder means having a movable piston disposed therein are provided operably connected to the device. The device is positioned manually at a desired setting, and upon the receipt of and in response to a physical signal a control signal is generated which is utilized to cause the introduction of pressurized hydraulic fluid into the hydraulic cylinder means on a selected side of the movable piston thereby moving the piston and the device in a desired direction and displacing hydraulic fluid on the other side of the piston. The displaced hydraulic fluid is stored throughout the duration of the physical signal, and upon the withdrawal thereof, the stored hydraulic fluid is reintroduced into the hydraulic cylinder means on the side of the piston from which it was displaced thereby restoring the piston and the device to the setting occupied prior to the receipt of the physical signal.

Claims

1. Positioner apparatus for positioning a device manually, but automatically moving the device to a different desired position in response to a physical signal, and then repositioning the device to the original setting thereof upon the withdrawal of said physical signal comprising:

a. a hydraulic cylinder having a movable piston disposed therein operably connected to said device;

b. a source of pressurized hydraulic fluid;

c. first conduit means connecting said source of pressurized hydraulic fluid to opposite ends of said hydraulic cylinder;

d. first valve means disposed in said first conduit means for manually introducing or withdrawing pressurized hydraulic fluid into and from said hydraulic cylinder so that said piston can be selectively moved to desired positions therein;

e. accumulator means for temporarily storing hydraulic fluid;

f. second conduit means connected between said accumulator means and a selected end of said hydraulic cylinder;

g. second valve means disposed in said second conduit means for selectively causing hydraulic fluid displaced from said hydraulic cylinder to be transferred into said accumulator means or hydraulic fluid stored in said accumulator means to be transferred back into said hydraulic cylinder; and

h. control means responsive to said physical signal and operably connected to said first and second valve means so that upon receipt of said physical signal said valve means are operated to cause said pressurized hydraulic fluid to be introduced by way of said first conduit means into a selected end of said hydraulic cylinder thereby moving said piston in a desired direction and hydraulic fluid displaced by the movement of said piston to be transferred by way of said second conduit means into said accumulator means, and upon the withdrawal of said physical signal, the hydraulic fluid stored in said accumulator means to be transferred back into the end of said hydraulic cylinder from which it was displaced thereby restoring said piston to the position it occupied prior to the receipt of said physical signal.

2. The apparatus of claim 1 wherein said accumulator means for temporarily storing hydraulic fluid comprises:

an elongated cylinder having a forward end and a rearward end and having a movable piston disposed therein;

means connected to the rearward end of said cylinder for urging said piston toward the forward end thereof; and

said second conduit means being connected to the forward end of said cylinder so that when displaced hydraulic fluid is introduced thereinto said piston is moved from the forward end toward the rearward end thereof and when hydraulic fluid is withdrawn therefrom said piston is moved back to the forawrd end thereof by said means urging said piston toward the forward end thereof.

3. The apparatus of claim 2 wherein said means for urging said piston toward the forward end of said cylinder comprises:

third conduit means connected to said source of pressurized hydraulic fluid and to the rearward end of said cylinder; and

third valve means for introducing or withdrawing said pressurized hydraulic fluid into and from said rearward end of said cylinder operably connected to said control means whereby when displaced hydraulic fluid is introduced into the forward end of said cylinder, hydraulic fluid is withdrawn from the rearward end thereof, and when stored hydraulic fluid is withdrawn from the forward end of said cylinder, pressurized hydraulic fluid is introduced into the rearward end thereof.

4. The apparatus of claim 3 wherein said control means responsive to said physical signal comprises:

means for receiving said physical signal and generating a first control signal in response thereto, said first control signal being operably connected to said first, second and third valve means; and

means for generating a second control signal operably connected to said piston disposed in said elongated cylinder whereby said second control signal is generated when said piston occupies positions within said cylinder other than at the forward end thereof, said second control signal being operably connected to said first and second valve means so that upon withdrawal of said physical signal and said first control signal, said second control signal maintains said first and second valve means in the same position as did the first control signal until the hydraulic fluid stored in said cylinder is displaced therefrom and said piston occupies a position at the forward end of said cylinder.

5. Positioner apparatus for controlling the operation of a device in response to a physical signal, said apparatus having the capability of automatically repositioning to an original setting which comprises:

a. first hydraulic cylinder means having a movable piston disposed therein operably connected to said device;

b. a source of pressurized hydraulic fluid;

c. first conduit means connecting said source of pressurized hydraulic fluid to opposite ends of said first hydraulic cylinder;

d. first valve means disposed in said first conduit means for selectively introducing or withdrawing pressurized hydraulic fluid into and from said first hydraulic cylinder means so that said piston can be selectively moved to desired positions therein;

e. second hydraulic cylinder means having first and second ends and a movable piston disposed therein;

f. means attached to said second hydraulic cylinder means for urging said movable piston toward the first end thereof;

g. second conduit means connected to the first end of said second hydraulic cylinder means and to a selected end of said first hydraulic cylinder means;

h. second valve means disposed in said second conduit means for selectively causing hydraulic fluid displaced from said first hydraulic cylinder means by the movement of said piston therein to be transferred through said second conduit means into said second hydraulic cylinder means;

i. control means responsive to said physical signal and operably connected to said first and second valve means so that upon receipt of said physical signal said valve means are operated to cause said pressurized hydraulic fluid to be introduced by way of said first conduit means into a selected end of said first hydraulic cylinder means tHereby moving the piston disposed therein in a desired direction, and to cause hydraulic fluid displaced by the movement of said piston to be transferred by way of said second conduit means into said second hydraulic cylinder means moving the piston disposed therein toward the second end thereof, and upon the withdrawal of said physical signal, the hydraulic fluid stored in said second hydraulic cylinder means is caused by said means urging said piston therein toward the first end thereof to be transferred back into said first hydraulic cylinder means thereby restoring said piston disposed therein to the position it occupied prior to the receipt of said physical signal.

6. The apparatus of claim 5 wherein the means for urging said movable piston in said second hydraulic cylinder means toward the first end thereof comprises:

third conduit means connected to said source of pressurized hydraulic fluid and to the second end of said second hydraulic cylinder means; and

third valve means disposed in said third conduit means and operably connected to said control means for introducing or withdrawing pressurized hydraulic fluid into and from the second end of said second hydraulic cylinder means whereby when displaced hydraulic fluid from said first hydraulic cylinder means is introduced into the first end of said second hydraulic cylinder means, hydraulic fluid is withdrawn from the second end thereof, and when the stored hydraulic fluid is withdrawn from the first end of said second hydraulic cylinder means, said pressurized hydraulic fluid is introduced into the second end thereof.

7. The apparatus of claim 6 wherein said source of pressurized hydraulic fluid comprises:

an accumulator for containing a supply of hydraulic fluid including inlet and outlet connections;

pump means for generating a stream of pressurized hydraulic fluid having suction and discharge connections; and

conduit means connected between the outlet connection of said accumulator and the suction connection of said pump means.

8. The apparatus of claim 7 which is further characterized to include fifth conduit means connected between the inlet connection of said hydraulic fluid accumulator and to said first, second and third valve means so that pressurized hydraulic fluid withdrawn from said first and second hydraulic cylinder means is caused to be returned to said hydraulic fluid accumulator by way of said fifth conduit means.

9. A method of automatically changing the position of a device operated by manually controllable hydraulic cylinder means which includes a movable piston connected to said device in response to a physical signal, and then repositioning said device to its original setting upon the withdrawal of said physical signal comprising the steps of:

a. generating a control signal in response to said physical signal;

b. utilizing said control signal to operate the movable piston of said hydraulic cylinder means whereby pressurized hydraulic fluid is introduced into said hydraulic cylinder means on a selected side of said movable piston therein to move said piston in a desired direction and to displace hydraulic fluid from the other side of said piston;

c. storing the hydraulic fluid displaced from said hydraulic cylinder means throughout the duration of said physical signal; and

d. then reintroducing said stored hydraulic fluid into said hydraulic cylinder means on the side of said piston from which it was displaced thereby restoring said piston to the position it occupied prior to the receipt of said physical signal.

10. The method of claim 9 wherein the step of storing said displaced hydraulic fluid is further defined to include the step of:

introducing said displaced hydraulic fluid into one end of an elongated cylinder having a movable piston disposed therein so that said piston is moved toward the opposite end of said cylinder by said fluid and said fluid is stored therein.

11. The method of claim 10 wherein the steP of reintroducing said stored hydraulic fluid into said hydraulic cylinder means is further defined to include the step of:

returning said piston disposed in said elongated cylinder to the position it occupied prior to the introduction of said displaced hydraulic fluid therein thereby displacing said stored hydraulic fluid from said elongated cylinder into said hydraulic cylinder means.