Differential volume sensing hydraulic control
AssigneePredator Systems Inc.
InventorsGordon Yowell, Stephen Kaylor, Duane Samuelson, Alvin S. Blum
Life of this patent
Estimating the term…
Abstract
A valve assembly senses the cumulative volume of hydraulic fluid that has passed to an actuator and senses and subtracts from that cumulative volume the volume of return fluid that has passed from the actuator. When the difference between the volumes exceeds a preset value, the system shuts off the flow to the actuator to prevent further loss of fluid from a leak. The assembly may employ separate sensors in separate pressure and return lines or a common line with a common sensor which reverses signal polarity when flow reverses. Target flowmeters with signal adding and subtracting circuits may provide the differential volume information.
Claims18
A differential volume sensing shut off valve assembly to be installed in the hydraulic fluid pressure and return lines between upstream and downstream portions of a hydraulic circuit for isolating the circuit in response to a leakage of a predetermined volume of fluid therefrom, the valve assembly comprising:
- a valve body having a first entrance port and a first exit port for connectably interposing in the fluid pressure line of the upstream portion of the hydraulic circuit and a second entrance port and a second exit port for connectably interposing in the fluid return line of the downstream portion of the hydraulic circuit;
- a first channel in the valve body connecting the first entrance port to the first exit port;
- a second channel in the valve body connecting the second entrance port to the second exit port;
- first sensing means in the first channel for sensing volume of fluid flowing therethrough;
- second sensing means in the second channel for sensing volume of fluid flowing therethrough;
- first summing means in the valve body operatively connected to the first sensing means for accumulating volume of fluid flow information on fluid flowing in the first channel;
- second summing means in the valve body operatively connected to the second sensing means for accumulating volume of fluid flow information on fluid flowing in the second channel;
- difference determining means connected to the first and second summing means for determining the difference between the cumulative fluid flow volume information in the first and second channels;
- storage means in the valve body for storing a preset differential cumulative volume value;
- comparator means in the valve body connected to the storage means and the difference determining means for generating a shut off signal when the difference between the cumulative fluid flow volume information in the first and second channels exceeds the preset differential cumulative volume value;
- and
- valve means in the valve body in at least one of the first and second channels for shutting off the fluid flow therein when a shut off signal is received, the valve means being operatively connected to the comparator means.
A differential volume sensing shut off valve assembly to be installed in the hydraulic fluid pressure and return lines between upstream and downstream portions of a hydraulic circuit for isolating the circuit in response to a leakage of a predetermined volume of fluid therefrom, the valve assembly comprising:
- a first entrance port and a first exit port for connectably interposing in the fluid pressure line of the upstream portion of the hydraulic circuit and a second entrance port and a second exit port for connectably interposing in the fluid return line of the downstream portion of the hydraulic circuit;
- a first channel connecting the first entrance port to the first exit port;
- a second channel connecting the second entrance port to the second exit port;
- first sensing means in the first channel for sensing volume of fluid flowing therethrough;
- second sensing means in the second channel for sensing volume of fluid flowing therethrough;
- first summing means operatively connected to the first sensing means for accumulating volume of fluid flow information on fluid flowing in the first channel;
- second summing means operatively connected to the second sensing means for accumulating volume of fluid flow information on fluid flowing in the second channel;
- difference determining means connected to the first and second summing means for determining the difference between the cumulative fluid flow volume information in the first and second channels;
- storage means for storing a preset differential cumulative volume value;
- comparator means connected to the storage means and the difference determining means for generating a shut off signal when the difference between the cumulative fluid flow volume information in the first and second channels exceeds the preset differential cumulative volume value;
- and
- valve means in at least one of the first and second channels for shutting off the fluid flow therein when a shut off signal is received, the valve means being operatively connected to the comparator means.
A differential volume sensing shut off valve assembly adapted to be installed in a hydraulic circuit for supplying hydraulic fluid to, and receiving hydraulic fluid from a hydraulic actuator for isolating the circuit in response to a leakage of a predetermined volume of fluid therefrom, the valve comprising:
- at least one entrance port and at least one exit port adapted for connectably interposing in fluid connection with a hydraulic pressure source at the at least one entrance port and with a hydraulic actuator at the at least one exit port;
- first means for sensing volume of fluid flowing between at least one entrance port and at least one exit port;
- second means for sensing volume of fluid flowing between at least one exit port and at least one entrance port;
- first summing means operatively connected to the first sensing means for accumulating volume of fluid flow information on fluid flowing from at least one entrance port to at least one exit port;
- second summing means operatively connected to the second sensing means for accumulating volume of fluid flow information on fluid flowing from at least one exit port to at least one entrance port;
- difference determining means connected to the first and second summing means for determining the difference between the cumulative fluid flow volume information received from the first and second summing means;
- storage means for storing a preset differential cumulative volume value;
- comparator means connected to the storage means and the difference determining means for generating a shut off signal when the determined difference between the first and second summing means exceeds the preset differential cumulative volume value;
- and
- valve means for shutting off fluid flow when a shut off signal is received, the valve means being operatively connected to the comparator means, and in fluid connection with at least one entrance port.
Dependencies are inferred from the claim text.