Remote control apparatus for hydraulically actuated devices

A remote control apparatus for positioning the throttling mechanism of a throttling valve fixedly mounted in a conduit at a first location, said throttling mechanism being adapted to progressively open, remain stationary and progressively close in response to varied hydraulic pressures applied to a first end and/or an opposed second end of a hydraulic operating means mechanically coupled to said throttling mechanism, said control apparatus comprising:

• a hydraulic control valve having a valve stem with first, second and third valve stem positions;
• first hydraulic means fluid-tightly interconnecting said hydraulic control valve and said hydraulic operating means, said first hydraulic means being adapted (a) to apply a higher pressure to said first end of said hydraulic operating means than is applied to said second end of said hydraulic operating means when said valve stem is in said first valve stem position, thereby progressively opening said throttling mechanism, (b) to equalize the pressures applied to said first and second ends of said hydraulic operating means when said valve stem is in said second valve stem position thereby maintaining said throttling mechanism in a stationary position, and (c) to apply a higher pressure to said second end of said hydraulic operating means when said valve stem is in said third valve stem position, thereby progressively closing said throttling mechanism;
• pneumatic means comprising (1) a pneumatic operating means mechanically coupled to said valve stem and adapted to controllably adjust the position of said valve stem among said first, second and third valve stem positions in response to variations in a superatmospheric pneumatic pressure normally applied to a first end and an opposed second end of said pneumatic means, and (2) electronically controlled venting means fluid-tightly connected to said first and second ends of said pneumatic operating means;
• a manually switchable electrical switch mounted at a second location spaced from said first location, said electrical switch having first, second and third switch positions;
• electrical means interconnecting said electrical switch and said venting means, said venting means being adapted to (a) vent pneumatic fluid from said second end of said pneumatic operating means to thereby adjust said valve stem to said first valve stem position when said electrical switch is in said first switch position, (b) prohibit venting of pneumatic fluid from said first and second ends of said pneumatic operating means to thereby adjust said valve stem to said second valve stem position when said electrical switch is in said second switch position, and (c) vent pneumatic fluid from said first end of said pneumatic operating means to thereby adjust said valve stem to said third valve stem position when said electrical switch is in said third switch position.

A remote control apparatus for positioning the throttling mechanism of a throttling valve fixedly mounted in a fluid flow conduit at a first location, said throttling mechanism being adapted to progressively open, remain stationary and progressively close in response to varied hydraulic pressures applied to a first end and/or an opposed second end of a hydraulic operating means mechanically coupled to said throttling mechanism, said control apparatus comprising:

• first hydraulic means comprising (1) a hydraulic control valve having a valve stem with first, second and third valve stem positions;
• (2) a source of pressurized hydraulic fluid;
• (3) a hydraulic fluid sump;
• and (4) conduit means fluid-tightly connecting said hydraulic control valve to said first and second ends of said hydraulic operating means and to the hydraulic fluid source and the hydraulic fluid sump, said first hydraulic means being adapted (a) to apply a higher pressure to said first end of said hydraulic operating means than is applied to said second end of said hydraulic operating means when said valve stem is in said first valve stem position, thereby progressively opening said throttling mechanism, (b) to equalize the pressures applied to said first and second ends of said hydraulic operating means when said valve stem is in said second valve stem position, thereby maintaining said throttling mechanism in a stationary position, and (c) to apply a higher pressure to said second end of said hydraulic operating means than is applied to said first end of said hydraulic operating means when said valve stem is in said third valve stem position, thereby progressively closing said throttling mechanism;
• pneumatic means comprising (1) a pneumatic operating means mechanically coupled to said valve stem and adapted to adjust the position of said valve stem among said first, second and third valve stem positions in response to varied pneumatic pressures applied to a first end and/or an opposed second end of said pneumatic operating means, (2) a source of pressurized pneumatic fluid fluid-tightly connected to said first and second ends of said pneumatic operating means;
• and (3) electronically controlled venting means fluid-tightly connected to said first and second ends of said pneumatic operating means, said venting means being adapted to controllably vent pneumatic fluid from said first and second ends of said pneumatic operating means;
• and
• electrical control means comprising (1) a manually switchable electrical switch mounted at a second location spaced from said first location, said electrical switch having first, second and third switch positions, and (2) electrical conductor means interconnecting said electrical switch and said venting means, said electrical control means being adapted to (a) maintain pneumatic pressure on said first end of said pneumatic operating means and vent pneumatic fluid from said second end of said pneumatic operating means through said venting means to thereby adjust said valve stem to said first valve stem position when said electrical switch is in said first switch position, (b) prohibit venting of pneumatic fluid from said first and second ends of said pneumatic operating means to thereby adjust said valve stem to said second valve stem position when said electrical switch is in said second switch position, and (c) maintain pneumatic pressure on said second end of said pneumatic operating means and vent pneumatic fluid from said first end of said pneumatic operating means through said venting means to thereby adjust said valve stem to said third valve stem position when said electrical switch is in said third switch position.

A remote control apparatus for positioning a hydraulically-actuated mechanism adapted to move progressively in a first direction, remain stationary and move progressively in a second direction in response to varied hydraulic pressures applied to a first end and/or an opposed second end of a hydraulic operating means mechanically coupled to said mechanism, said control apparatus comprising:

• first hydraulic means comprising (1) a hydraulic control valve having a valve stem with first, second and third valve stem positions;
• (2) a source of pressurized hydraulic fluid;
• (3) a hydraulic fluid sump;
• and (4) conduit means fluid-tightly connecting said hydraulic control valve to said first and second ends of said hydraulic operating means and to the hydraulic fluid source and the hydraulic fluid sump, said first hydraulic means being adapted (a) to apply a higher pressure to said first end of said hydraulic operating means than is applied to said second end of said hydraulic operating means when said valve stem is in said first valve stem position, thereby progressively opening said mechanism, (b) to equalize the pressures applied to said first and second ends of said hydraulic operating means when said valve stem is in said second valve stem position, thereby maintaining said mechanism in a stationary position, and (c) to apply a higher pressure to said second end of said hydraulic operating means than is applied to said first end of said hydraulic operating means when said valve stem is in said third valve stem position, thereby progressively closing said mechanism;
• pneumatic means comprising (1) a pneumatic operating means mechanically coupled to said valve stem and adapted to adjust the position of said valve stem among said first, second and third valve stem positions in response to varied pneumatic pressures applied to a first end and/or an opposed second end of said pneumatic operating means, (2) a source of pressurized pneumatic fluid fluid-tightly connected to said first and second ends of said pneumatic operating means;
• and (3) electronically controlled venting means fluid-tightly connected to said first and second ends of said pneumatic operating means, said venting means being adapted to controllably vent pneumatic fluid from said first and second ends of said pneumatic operating means;
• and
• electrical control means comprising (1) a manually switchable electrical switch mounted at a second location spaced from said first location, said electrical switch having first, second and third switch positions, and (2) electrical conductor means interconnecting said electrical switch and said venting means, said electrical control means being adapted to (a) maintain pneumatic pressure on said first end of said pneumatic operating means and vent pneumatic fluid from said second end of said pneumatic operating means through said venting means to thereby adjust said valve stem to said first valve stem position when said electrical switch is in said first switch position, (b) prohibit venting of pneumatic fluid from said first and second ends of said pneumatic operating means to thereby adjust said valve stem to said second valve stem position when said electrical switch is in said second switch position and (c) maintain pneumatic pressure on said second end of said pneumatic operating means and vent pneumatic fluid from said first end of said pneumatic operating means through said venting means to thereby adjust said valve stem to said third valve stem position when said electrical switch is in said third switch position.