Valve operating mechanism

Claim 2

An improved valve operating mechanism for use in a well pumping apparatus wherein a beam is pivotally supported for rocking movement, an hydraulic operating mechanism is connected to said beam for rocking said beam about its pivot support between predetermined upper and lower limits and includes a cylinder means having fluid connections to a source of pressurized hydraulic fluid, said fluid connections including valve means having a control arm movable between first and second operative positions for controlling the flow of hydraulic fluid to and from said cylinder means and said valve operating mechanism is controlled by the rocking movement of said beam and is arranged to quickly switch said control arm to one or the other of its operative positions to reverse the rocking movement of said beam as it approaches one of its predetermined upper and lower limits, said valve operating mechanism including a control rod connected to said beam and arranged for reciprocating movement during rocking movement of said beam, at least one tripping block secured to said control rod, a swing arm movable between first and second positions corresponding to said first and second operative positions of said control arm, and having a portion thereof which has means for receiving an impulse from said tripping block through an impulse transmitting means during a stroke of said reciprocating control rod for moving said swing arm toward one of said first and second positions thereof, a switching means operatively associated with said control arm and connected to said swing arm at a point spaced from said portion thereof and means connected at one end to said swing arm and at another end to a point spaced from said swing arm for exerting a tension force on said swing arm, said tension exerting means being operative in response to movement of said swing arm by an impulse to move said swing arm to one of said first and second positions to move said switching means and thereby move said control arm to one of said first and second operative positions.

Claim 3

A valve operating mechanism according to claim 1 in which said valve switching means comprises a fork arrangement which is arranged to straddle a portion of said control arm extending from said valve means.

Claim 4

A valve operating mechanism according to claim 1 including a guide arm having a first portion which is connected to said valve switching means and to said swing arm and a second portion which is pivotally mounted on a pivot axis, said guide arm serving to maintain said valve switching means operatively associated with said control arm of said valve means during movement of said control arm to and from said first and second operative positions.

Claim 5

A valve operating mechanism according to claim 1 in which said tensioning means is fixedly secured at one end to said swing arm and is adjustable secured at another end to a support spaced from said swing arm.

Claim 6

A valve operating mechanism according to claim 4 in which said swing arm is elongated and hollow and said one end of said tensioning means extends into and is secured to said hollow swing arm.

Claim 7

A valve operating mechanism according to claim 1 wherein said impulse transmitting means is a toggle actuator which is mounted for pivoting movement about a pivot Axis, said toggle actuator having a projecting portion which is positioned to receive an impulse from said tripping block for transmitting said impulse to said swing arm and to permit said tripping block to move past said projecting portion during overshoot movement of said control rod carrying said tripping block, said projecting portion being moved by said tripping block out of the path of said tripping block during overshoot movement of said control rod.

Claim 8

A valve operating mechanism according to claim 6 in which said toggle actuator has a recess therein and said means on said swing arm for receiving an impulse comprises a projection extending from said swing arm into said recess.

Claim 9

A valve operating mechanism according to claim 7 in which said recess in said toggle actuator extends into said actuator in a direction parallel to the pivot axis of said actuator and has a generally U-shaped cross section.

Claim 10

A valve operating mechanism according to claim 1 in which at least one tripping block is adjustably positioned on said control rod for adjusting the extent of the stroke of the control rod to thereby adjust the extent of rocking movement of the beam.

Claim 11

A valve operating mechanism according to claim 1 in which two tripping blocks are adjustably positioned on and secured to said control rod.

Claim 12

In a well pumping apparatus, the combination of: a beam pivotally supported for rocking movement, an hydraulic operating mechanism connected to said beam for rocking said beam about its pivot support between predetermined upper and lower limits and including a cylinder means having fluid connections to a source of pressurized hydraulic fluid, said fluid connections including valve means of the type having a valve housing and a control arm which extends from the housing and which is movable between first and second operative positions for controlling the flow of hydraulic fluid to and from said cylinder means and a valve operating mechanism controlled by the rocking movement of said beam and arranged to quickly switch said control arm from one of its operative positions to the other of its operative positions to reverse the rocking movement of said beam as it approaches one of its predetermined upper and lower limits, said valve operating mechanism including a control rod connected to said beam and arranged for reciprocating movement during rocking movement of said beam, at least one tripping block secured on said control rod, a swing arm movable between first and second positions corresponding to said first and second operative positions of said control arm and having a portion thereof which has means for receiving an impulse from said tripping block through an impulse transmitting means during a stroke of said reciprocating control rod for moving said swing arm toward one of said first and second positions thereof, a switching means operatively associated with said control arm and connected to said swing arm at a point spaced from said portion thereof and means connected at one end to said swing arm and at another end to a point spaced from said swing arm for exerting a tension force on said swing arm, said tension exerting means being operative in response to movement of said swing arm by an impulse to move said swing arm to one of said first and second positions to move said switching means to move said control arm to one of said first and second operative positions.

Claim 13

In a well pumping apparatus, the combination of: a beam pivotally supported for rocking movement, an hydraulic operating mechanism connected to said beam for rocking said beam about its pivot support between predetermined upper and lower limits and including a cylinder means having fluid connections to a source of pressurized hydraulic fluid, said fluid connections including valve means of the type having a valve housing and a control arm which extends from the housing and which is movable between first and second operative positions for controlling the flow of hydraulic fluid to and from said cylinder means and a valve operating mechanism controlled by the rocking movement of said beam and arranged to quickly switch said control arm from one of its operative positions to the other of its operative positions to reverse the rocking movement of said beam as it approaches one of its predetermined upper and lower limits, said valve operating mechanism including a control rod connected to said beam and arranged for reciprocating movement during rocking movement of said beam, at least one tripping block secured on said control rod, a swing arm movable between first and second positions corresponding to said first and second operative positions of said control arm and having a portion thereof which has means for receiving an impulse from said tripping block through an impulse transmitting means during a stroke of said reciprocating control rod for moving said swing arm toward one of said first and second positions thereof, a switching means operatively associated with said control arm and connected to said swing arm at a point spaced from said portion thereof and means connected at one end to said swing arm and at another end to a point spaced from said swing arm for exerting a tension force on said swing arm, said tension exerting means being operative in response to movement of said swing arm by an impulse to move said swing arm to one of said first and second positions to move said switching means to move said control arm to one of said first and second operative positions.

Claim 14

A pumping apparatus according to claim 11 in which said valve operating mechanism includes a mounting bar which is secured to and supported by said valve housing, and said tensioning means is supported by said mounting bar.

Claim 15

A pumping apparatus according to claim 12 including a guide arm having a first portion which is connected to said valve switching means and to said swing arm and a second portion which is mounted for pivotal movement about a pivot axis between said mounting bar and said valve housing.

Claim 16

A pumping apparatus according to claim 12 wherein said impulse tRansmitting means is a toggle actuator which is mounted for pivotal movement about a pivot axis adjacent said mounting bar, said toggle actuator having a projecting portion which is adapted to receive impulses from said tripping block for transmitting said impulses to said portion of said swing arm and to permit said tripping block to move past said projecting portion during overshoot movement of said control rod carrying said tripping block, said projecting portion being moved by said tripping block out of the path of said tripping block during overshoot movement of said control rod.