Patents by Inventor David C. H. Grant
David C. H. Grant has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 5503175Abstract: A water safety valve, system and method for detecting and shutting off water flow due to leaks or breaks in a water line in which the water flow is at a very low rate on the order of three to five fluid ounces per minute but having the capability of passing large flows of three hundred to five hundred times this amount. The system provides an automatic fluid shut off with an over-ride timer with an automatic return to normal operation when a predetermined period has expired. It further allows simple shut off and activation of the system with a single conveniently located control.Type: GrantFiled: December 22, 1994Date of Patent: April 2, 1996Inventors: Paul W. Ravilious, David C. H. Grant
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Patent number: 5346534Abstract: A system for processing a product with a solvent containing volatile constituents, the system including a pressure chamber for receiving the product, a vacuum pump for evacuating the chamber, a solvent recirculating system for admitting the solvent at a predetermined pressure into the chamber, the solvent recirculating system including a heater for maintaining the temperature of the chamber at the saturation temperature of the solvent, gas liquid separator for separating the gas and liquid components of the solvent discharged from the chamber, a first closed loop system connected to the separator to return the gas constituent to the chamber and a second closed loop system connected to the separator to return the liquid component to the chamber.Type: GrantFiled: June 2, 1993Date of Patent: September 13, 1994Assignee: Baxter International Inc.Inventor: David C. H. Grant
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Patent number: 5343885Abstract: A vacuum air lock assembly for transferring an article into an enclosure for treating the article with a solvent, the enclosure including a door for admitting the article into or out of the enclosure, the assembly including a chamber mounted on the enclosure and having an outer door, the chamber being sealed to the enclosure for transferring the article from the chamber through the enclosure door into the enclosure, a vacuum pump for drawing a vacuum in the chamber and discharging the air to atmosphere, the chamber being connected to the enclosure to break the vacuum in the chamber with solvent vapor from the enclosure, the article is transferred into the enclosure through the enclosure door for treatment and returned to the chamber after treatment, and the solvent vapor in the chamber is returned to the enclosure chamber through the vacuum pump and the vacuum in the chamber is broken to atmosphere.Type: GrantFiled: March 4, 1992Date of Patent: September 6, 1994Assignee: Baxter International Inc.Inventor: David C. H. Grant
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Patent number: 5304253Abstract: A method is provided for cleaning an article with a solvent having a boiling point such that the solvent is a gas at room temperature and one atmosphere pressure. Such a method includes the steps of disposing the article in a chamber, introducing the solvent into the chamber so that the solvent contacts the article, pressurizing the chamber so that the solvent is in a liquid state and removes contaminants from the article, purging the chamber to remove the solvent, and removing the treated article from the chamber. Such a system permits the use of liquids having boiling points lower than room temperature, such as certain C.sub.1 -C.sub.4 halocarbons, which liquids have not previously been used as cleaning solvents.Type: GrantFiled: February 25, 1992Date of Patent: April 19, 1994Assignee: Baxter International Inc.Inventor: David C. H. Grant
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Patent number: 5232476Abstract: A system for processing a product with a solvent containing volatile constituents, the system including a pressure chamber for receiving the product, a vacuum pump for evacuating the chamber, a solvent recirculating system for admitting the solvent at a predetermined pressure into the chamber, the solvent recirculating system including a heater for maintaining the temperature of the chamber at the saturation temperature of the solvent, gas liquid separator for separating the gas and liquid components of the solvent discharged from the chamber, a first closed loop system connected to the separator to return the gas constituent to the chamber and a second closed loop system connected to the separator to return the liquid component to the chamber.Type: GrantFiled: March 6, 1992Date of Patent: August 3, 1993Assignee: Baxter International Inc.Inventor: David C. H. Grant
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Patent number: 5192340Abstract: An emission control system for a fluid composition comprised of volatile constituents used to clean a hollow fiber filter or capillary flow dialyzer including a housing having a chamber for receiving the dialyzer, a control system is used for establishing a desired environment in the chamber, the dialyzer and the fibers, a separator operatively associated with the chamber for separating gas and liquid components of the fluid composition, a stripper connected to the separator for fractionating lower boiling point volatiles from the gas to return the higher boiling point volatiles to the fluid phase and yield a stripped or solvent humidified gas and a delivery system for routing the stripped gas to the chamber dialyzer and fibers as a drying agent.Type: GrantFiled: February 21, 1992Date of Patent: March 9, 1993Assignee: Baxter International, Inc.Inventors: David C. H. Grant, Randolph H. Watkins, Robert M. Sluga, Steven J. Wurgler, Gregory D. Mills, Dennis C. Berry, Jerry D. Fisher
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Patent number: 5176187Abstract: A process and apparatus for evacuating refrigerant for recovery from a conventional refrigeration sytems, e.g. automobile air conditions, preferably by attachment to a manifold having multiple evacuation devices, e.g. compressor, vacuum pump, transfer pump with the evacuation devices discharging through self-closing quick connect valves into at least one flexible accumulator, e.g. a bag mounted onto a manifold, and with an additional transfer pump evacuating the bag gradually to a recovery system which can be a conventional refrigerant recovery condensing unit with purification. Facilities for receiving bags filled from refrigeration systems which are remote from the system, e.g. home refrigerators, can be provided to weigh the contents into the manifold for recovery.Type: GrantFiled: October 18, 1990Date of Patent: January 5, 1993Assignee: Ashland Oil, Inc.Inventor: David C. H. Grant
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Patent number: 5106404Abstract: A system and method for controlling atmospheric emission of volatile materials such as solvents, used to clean or treat articles incident to their manufacture comprising a treatment chamber and a recirculating closed loop gas and solvent recovery system. The chamber is isolated from the closed loop system, the article to be treated is put into the chamber, the chamber is sealed and gases removed by evacuation, these gases being discharged outside the closed loop system. The articles are treated with solvent, dried with a fluid derived in the solvent recovery system from noncondensable gas, residual in the system. Drying is effected by passing the recovered gases from the closed loop system through the chamber and by evacuation. The gas evacuated from the chamber, containing solvent vapor is retained within the closed loop system. The chamber is vented to outside the closed loop system prior to removing the treated item.Type: GrantFiled: September 12, 1990Date of Patent: April 21, 1992Assignee: Baxter International Inc.Inventor: David C. H. Grant
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Patent number: 5094277Abstract: A refrigerant recovery and purification system employs a centrifugal separator connected to a disabled automotive air conditioning system and connects a slack-sided accumulator to a reclaim condenser chamber. Oil and contaminants are separated by centrifugal action from the incoming refrigerant. Condensing of reclaimed refrigerant vapor in a condenser produces a vacuum pressure causing vapor to flow from the slack-sided accumulator. A conventional refrigeration system supplies refrigerant to a first evaporator coil and to a second evaporator coil surrounding a liquid receiver connected by a conduit with the reclaim condenser. A power cylinder axially vertically positioned above a vertically upright refrigerated block drives a piston rod connected to a T-shaped piston screw small diameter shank projecting through a slightly larger diameter bore within the bottom of an upwardly open cup-shaped piston slidable within the refrigerated block receiver chamber.Type: GrantFiled: October 19, 1990Date of Patent: March 10, 1992Assignee: Ashland Oil Inc.Inventor: David C. H. Grant
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Patent number: 5058631Abstract: A process and system for recovering refrigerant from refrigeration systems without substantial contamination of the atmosphere. The system includes devices for removing refrigerant from the system under the vapor pressure of the refrigerant or with aid from a pump, a conduit for conveying the refrigerant from the system, and a collapsible bag constructed of a flexible material substantially impermeable to refrigerant and to air, having at least one inlet for introducing refrigerant to be salvaged and sealing means for sealing the inlet on the bag. After filling, the bags may be transported to a recovery system for recovering refrigerant from the bag so that the refrigerant may be purified and recovered for reuse.Type: GrantFiled: August 16, 1989Date of Patent: October 22, 1991Assignee: Ashland Oil, Inc.Inventor: David C. H. Grant
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Patent number: 4969495Abstract: A refrigerant recovery and purification system particularly applicable to automotive air conditioning systems employs a centrifugal separator connected directly to the disabled automotive air conditioning system and which connects to a slack-sided accumulator and to a condenser chamber, all operating at near atmospheric pressure in a low pressure section. Oil and contaminants are separated by centrifugal action from the incoming refrigerant vapor stream and removed by gravity from the separator chamber. Condensing of the refrigerant vapor in the condenser produces a vacuum pressure for causing vapor to flow from the slack-sided accumulator to the condenser. A conventional refrigeration system supplies refrigerant liquid under pressure to a first evaporator coil within the condenser. The conventional refrigeration system also supplies high pressure liquid refrigerant to a second evaporator coil surrounding a liquid receiver connected by a conduit in series with the condenser and the accumulator.Type: GrantFiled: June 27, 1989Date of Patent: November 13, 1990Inventor: David. C. H. Grant
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Patent number: 4878931Abstract: Disclosed is a system for recovering vapor from an air/vapor process stream. The system is operated in two stages, a high temperature stage and a low temperature stage. The high temperature stage may be referred to as a condenser column. The low temperature stage is referred to as the stripper column. The air/solvent vapor stream is conducted first through the condenser column and then through the stripper column. A countercurrent flow of liquid solvent is provided to both the condenser column and the stripper column. In the low temperature stage (condenser column), the countercurrent flow of liquid solvent is at a temperature near but above the freezing point of water. This results in the removal of most of the solvent vapor and water vapor from the air/solvent vapor mixture.Type: GrantFiled: August 29, 1988Date of Patent: November 7, 1989Assignee: Quadrex HPS Inc.Inventor: David C. H. Grant