Method and apparatus for controlling leaks in pressurized fluid systems
First Claim
1. In a pressurized fluid system including at least one fluid conduit means and equipment associated with said conduit means, said system adapted to provide fluid at a line pressure to said fluid conduit means to operate said equipment upon initiation of a usage demand condition, apparatus for automatically controlling fluid leakage from existing points of leakage in said at least one fluid conduit means during non-use of said equipment, comprising:
- control unit means coupled into said fluid system including pressure reducing means upstream of said fluid conduit means for reducing the fluid pressure in said conduit means to a low pilot pressure so that during non-use of said equipment a first pilot leak fluid flow at pilot pressure exists in said conduit means through said existing points of leakage therein, said first pilot leak flow having a flow rate which varies continuously, and upon an initial actuation of said equipment a second pilot demand flow at pilot pressure exists in said conduit means, said second pilot demand fluid flow having a flow rate greater than said continuously varying flow rate of said first pilot leak flow, said control unit means further including main valve means for selectively isolating and effecting communication between line pressure and said conduit means in response to a signal;
said control unit means further including sensing means coupled into said conduit means between said pressure reducing means and said equipment for detecting and discriminating between said continuously varying flow rate of said first pilot leak flow and said flow rate of said second pilot demand flow, said sensing means comprising floating means for establishing a floating equilibrium position indicative of said continuously varying flow rate of said first pilot leak flow during non-use of said equipment and a target position indicative of said flow rate of said second pilot demand flow upon initial actuation of said equipment, said sensing means further including means for generating a signal upon sensing said flow rate of said second pilot demand flow and means for transmitting said signal to said main valve means of said control unit means for communicating said conduit means with line pressure.
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Accused Products
Abstract
Method and apparatus for controlling fluid leakage from sections of a pressurized fluid system adapted to provide fluid at line pressure to equipment associated therewith includes means for sensing first and second conditions indicative of non-use and of a usage demand respectively of the equipment and for generating a signal indicative of one of the conditions and control unit means for selectively isolating and effecting communication between line pressure of the fluid system and the system section in response to the condition-indicating signal. According to a first embodiment, the first non-use and second usage demand conditions are constituted by respective lower and higher rates of fluid flow through the section of the fluid system in which leakage is to be controlled. According to a second embodiment of the invention, the first non-use and second usage demand conditions are constituted by support and non-support of the equipment respectively or non-movement and movement of the equipment respectively.
18 Citations
21 Claims
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1. In a pressurized fluid system including at least one fluid conduit means and equipment associated with said conduit means, said system adapted to provide fluid at a line pressure to said fluid conduit means to operate said equipment upon initiation of a usage demand condition, apparatus for automatically controlling fluid leakage from existing points of leakage in said at least one fluid conduit means during non-use of said equipment, comprising:
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control unit means coupled into said fluid system including pressure reducing means upstream of said fluid conduit means for reducing the fluid pressure in said conduit means to a low pilot pressure so that during non-use of said equipment a first pilot leak fluid flow at pilot pressure exists in said conduit means through said existing points of leakage therein, said first pilot leak flow having a flow rate which varies continuously, and upon an initial actuation of said equipment a second pilot demand flow at pilot pressure exists in said conduit means, said second pilot demand fluid flow having a flow rate greater than said continuously varying flow rate of said first pilot leak flow, said control unit means further including main valve means for selectively isolating and effecting communication between line pressure and said conduit means in response to a signal; said control unit means further including sensing means coupled into said conduit means between said pressure reducing means and said equipment for detecting and discriminating between said continuously varying flow rate of said first pilot leak flow and said flow rate of said second pilot demand flow, said sensing means comprising floating means for establishing a floating equilibrium position indicative of said continuously varying flow rate of said first pilot leak flow during non-use of said equipment and a target position indicative of said flow rate of said second pilot demand flow upon initial actuation of said equipment, said sensing means further including means for generating a signal upon sensing said flow rate of said second pilot demand flow and means for transmitting said signal to said main valve means of said control unit means for communicating said conduit means with line pressure. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
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21. In a pressurized fluid system including at least one fluid conduit means and equipment associated with said conduit means, said system adapted to provide fluid at line pressure to said conduit means to operate said equipment upon initiation of a usage demand condition, and main valve means for selectively isolating and effecting communication between line pressure and said conduit means in response to a signal, a method for automatically controlling fluid leakage from existing points of leakage in said at least one conduit means during non-use of said equipment, comprising the steps of:
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reducing the fluid pressure in said conduit means to a low pilot pressure so that during non-use of said equipment a first pilot leak fluid flow at pilot pressure exists in said conduit means through said existing points of leakage therein, said first pilot leak flow having a flow rate which varies continuously, and so that upon initial actuation of the equipment a second pilot demand fluid flow at pilot pressure exists in said conduit means having a flow rate greater than said continuously varying flow rate of said first pilot leak flow; sensing and discriminating between said continuously varying flow rate of said first pilot leak flow and said flow rate of said second pilot demand flow, said sensing and discriminating step being carried out by providing means for establishing a floating equilibrium position indicative of said continuously varying flow rate of said first pilot leak flow during non-use of said equipment and for establishing a target position indicative of said flow rate of said second pilot demand flow upon initial actuation of said equipment; and generating a signal upon sensing said flow rate of said second pilot demand flow, and transmitting said signal to said main valve means for effecting communication of said conduit means with line pressure.
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Specification