Valves With Separate, Correlated, Actuators Patents (Class 137/637)
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Patent number: 4651773Abstract: A throttle valve assembly for displacing the plungers of at least two contiguous throttle valves in correspondence with the degree of throttle opening of an engine includes a first cam rotatably mounted on a stationary bracket fixed to the throttle valve bodies and having a cam face for displacing the plunger of the first throttle valve and an axially extending boss, a second cam rotatably mounted on the bracket and having a cam face for displacing the plunger of the second throttle valve and an axially extending boss, the first and second cams being coupled via coupling means formed on the opposing bosses, and a cable operatively associated with the engine torque demand for rotating the cams. The cam faces of the cams are formed to have a shape capable of providing the desired throttle pressure characteristic, the shapes of the cam faces differing from each other in order to obtain the optimum speed-change performance.Type: GrantFiled: July 5, 1985Date of Patent: March 24, 1987Assignees: Aisin Seiki Kabushiki Kaisha, Toyota Jodosha Kabushiki KaishaInventors: Shigeo Takahashi, Hiromi Hasegawa, Choji Furusawa, Kunio Morisawa
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Patent number: 4609013Abstract: A pressure modulator valve device having adjacent modulator valves, each including a sleeve, a plunger slidably fitted in the sleeve and a cam, the cams being connected to each other by a connecting member, a single supporting member for operatively supporting each of the cams and which is in contact with each sleeve so as to cover a front surface of each modulator valve, and a spring for biasing each sleeve in the direction of the single supporting member.Type: GrantFiled: March 6, 1985Date of Patent: September 2, 1986Assignees: Aisin Seiki Kabushiki Kaisha, Toyota Jidosha Kabushiki KaishaInventor: Shigeo Takahashi
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Patent number: 4526204Abstract: A two lever, three function control apparatus for hydraulic control valves wherein a first control lever end is connected by a first cable to a first hydraulic valve operator, a link perpendicular to the first cable interconnects the first control lever and one leg of a bellcrank rotatable about on axis parallel to the first control lever. A second leg of the bellcrank disposed at right angles to the first leg is connected to a second cable parallel to the first cable which in turn connects to a second hydraulic operator. Fore-and-aft movement of the first control lever actuate only the first cable and hydraulic valve and transverse movement of the first control lever actuates only the second cable and hydraulic valve. To physically differentiate between the two function, the second bellcrank leg is twice the length of the first leg and a detent mechanism acting on the bellcrank hub is also provided. A second control lever is connected by a third cable to a third hydraulic control valve operator.Type: GrantFiled: May 17, 1982Date of Patent: July 2, 1985Assignee: Dresser Industries, Inc.Inventor: Richard D. Primdahl
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Patent number: 4517935Abstract: The device comprises a rocker arm formed with a main bearing surface mounted on a main bearing and further bearing surfaces which co-operate with the upper ends of exhaust and inlet valves and pushrods respectively. Movement of one pushrod to open the inlet valve will turn the rocker arm a first axis and movement of the other pushrod to open the exhaust valve will turn the rocker arm about a second axis transverse to the first axis.Type: GrantFiled: February 23, 1983Date of Patent: May 21, 1985Inventor: Colin T. Pomfret
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Patent number: 4518011Abstract: A control valve cartridge which may be seated within the end plate of an actuator cylinder has a number of two way, two position solenoid valves placed in series axially and by way of which the space on each side of the piston may be connected by a respective control valve cartridge with a high pressure source or a low pressure source so as to give a programmable choke function.Type: GrantFiled: July 29, 1982Date of Patent: May 21, 1985Inventor: Kurt Stoll
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Patent number: 4467834Abstract: The supply conduits (1, 2) for two different gases to be mixted are each associated to a pressure regulator (3, 4) and lead into two chambers (5, 6) connected by chokes (7, 8) having a variable section area to a mixing chamber (9). A control member (13) allows the cross section area of the chokes (7, 8) to be varied without modifying the ratio between those cross section areas. Another control member (14) allows the ratio between those cross section areas to be varied without modifying the sum. This device allows a mixture of gases of any molecular weight in predetermined proportions.Type: GrantFiled: August 16, 1982Date of Patent: August 28, 1984Assignee: LN Industries S.A.Inventors: Jean-Denis Rochat, Conrad Zellweger
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Patent number: 4467833Abstract: A control valve and a multiple control system therefor for controlling a plurality of remotely positioned hydraulically actuated underwater devices. The control valve includes first and second equal size pilot pistons acted upon by first and second pilot ports, respectively, for moving the valve to either an open or closed position, and third and fourth unequal size pilot pistons acted upon by third and fourth pilot ports for moving the valve to either an open or closed position. The control valve may be operated in an electro-hydraulic control mode by the use of electrically actuated valves controlling the supply of fluid to the first and second ports. In addition, the control valve can be operated in a hydraulic mode by hydraulically controlling the supply of fluid to the third and fourth pilot ports.Type: GrantFiled: September 10, 1981Date of Patent: August 28, 1984Assignee: NL Industries, Inc.Inventors: Lawrence E. Satterwhite, Lawrence F. Angelo
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Patent number: 4460017Abstract: A flow diversion valve having first and second tubular spool housings joined at a contiguous edge to form an assembly, each of the housings having a flow passageway intermediate the housing ends, the passageways being opposite each other, and each of the housings having first and second ports formed in the sidewall spaced 90.degree.Type: GrantFiled: June 23, 1982Date of Patent: July 17, 1984Inventor: Wendell E. Robb
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Patent number: 4422619Abstract: A remote control system for controlling the movement of manually operable mechanisms such as hydraulic control valves for hydraulically operating the various cylinders on equipment such as cranes, or the like. A remote control unit includes a deadman switch and one or more potentiometers that provide control signals to a corresponding number of servo circuits. Each servo circuit drives a motor and a motor position sensing potentiometer that generates an error signal back to the servo. The motor rotation provides linear movement to the hydraulic control valve through a solenoid operated mechanical coupling. The servo circuit includes safety circuitry that detects open or shorted circuits in the cable to the remote unit and releases the solenoid coupling and returns the motor to a neutral position.Type: GrantFiled: July 21, 1981Date of Patent: December 27, 1983Inventor: Edward E. Griffiths
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Patent number: 4409902Abstract: A pair of air-operated hammers for driving railroad spikes are guided by separate yokes, raised and lowered by trunnion-mounted cylinders; a cross frame in a vertical plane is supported between the hammers and clamps join upright guides to the crossframe, the clamps enabling the hammers to be laterally adjusted on a main frame.Type: GrantFiled: April 20, 1981Date of Patent: October 18, 1983Assignee: Abex CorporationInventor: Earl E. Frank
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Patent number: 4398668Abstract: A showerhead control structure having an extending control operator, defining, a showerarm provided having a separate hot and cold water port for connection to existing hot and cold water supply lines in a showerstall wall comprising, a first pivotal ball and socket waterflow control valve structure to shut off the water flow in at least one pivotal position by swinging movement of the extending operator and in combination a second waterflow control valve structure to vary the water spray temperature and shut off the waterflow therethrough by rotational movement of the extending operator.Type: GrantFiled: May 26, 1981Date of Patent: August 16, 1983Inventor: Emile Jette
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Patent number: 4394969Abstract: A showerhead device assembly, independent of the need for faucet or faucets, including an extending control operator for controlling waterflow, water temperature and spray, comprising, a main housing having a passageway between a discharge mouth and an inlet providing a separate hot and cold water chamber for pivotal connection to a showerarm having a hot water port and a cold water port including discharges and an inlet connection, to a hot and cold water supply, including a first water temperature and flow control structure and a second waterflow and spray control structure connected with the extending operator, enabling a user to shut off and turn on waterflow through the showerhead, adjust the temperature of the water flowing therethrough and adjust the spray texture and direction by movement of the operator.Type: GrantFiled: February 10, 1981Date of Patent: July 26, 1983Inventor: Emile Jette
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Patent number: 4376450Abstract: A valve position monitoring and control system incorporates a proximity sensor positioned near a movable valve element to detect the operational position of the valve and includes circuit means coupled to a valve actuating solenoid for deactivating the solenoid in the event the valve fails to respond to command signals for positioning the valve in a predetermined position. In one embodiment, the system incorporates a pair of series connected valves used in presses which valves in turn are operated by solenoid actuated pilot valves. In the event either one of the valves do not operate either by opening within a predetermined time after actuation or closing within a predetermined time after their deactuation, the system of the present invention will not permit further operation of the valves until the system has been manually reset.Type: GrantFiled: July 3, 1978Date of Patent: March 15, 1983Assignee: Scovill Manufacturing Co. - Scovill, Inc.Inventors: Robert W. Fayfield, Kenneth B. Fontaine
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Patent number: 4313469Abstract: A faucet assembly including pinch valves for controlling the flow of hot and cold water. A base is secured to the deck of a sink from above the deck and a body secured to the base completes the faucet housing. A spout extends over the basin and includes an outlet at its end. Two flexible tubes are connected to a mixing chamber near the outlet and extend through the spout and through the base for connection to hot and cold water conduits remote from the sink deck. The tubes are normally pinched closed adjacent the mixing chamber by springs, and operating levers at opposite sides of the spout rotate about a shaft and operate a linkage and valve mechanism for overcoming the spring forces to permit flow. Lost motion connections render the spring closing forces independent of lever position. A cross bar limits lever movement and provides a support surface against which the tubes are pinched. The tubes are located in the valve region by a block which serves as a barrier to leakage.Type: GrantFiled: May 8, 1980Date of Patent: February 2, 1982Assignee: JH Industries, Inc.Inventor: Dwight N. Johnson
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Patent number: 4310026Abstract: Individual rotary flow control valves associated with and metering hydraulic fluid flow through one or more directional control valves mounted on a tractor frame are connected by flexible push-pull cables to respective control sectors located adjacent the tractor seat so that an operator may control the flow rate to a remote hydraulically driven or adjusted implement from the tractor seat.Type: GrantFiled: January 22, 1980Date of Patent: January 12, 1982Assignee: International Harvester CompanyInventors: Robert J. Oliver, Kenneth J. Lindblom, Lloyd B. Idelman, Carl S. Medo
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Patent number: 4270574Abstract: A mixing valve mechanism which is operable by a clockwork mechanism has a valve member which is movable in a valve chamber of the housing for opening and closing an outlet passage. The valve member has an upwardly extending follower portion which engages against a cam plate which is rotatably mounted in the housing above the follower. Spring means are provided for urging the follower of the valve member into engagement with the cam, and the cam has a control surface which during a portion of rotation of the cam moves the valve member downwardly into a closed position and which during another portion permits it to move upwardly under the action of the return spring. A handle member is mounted on the housing, and it is coupled by coupling means to the cam to rotate the cam to drive the clockwork during a portion of the rotational movement of the handle member and to lower valve member to close the passage during another portion of the movement.Type: GrantFiled: December 14, 1978Date of Patent: June 2, 1981Assignee: Aktiengesellschaft Karrer, Weber & CieInventor: Heinz Graber
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Patent number: 4268215Abstract: Two rotary air valves are mounted on the bucket control levers of an end loader and are operable to control the shifting of the loader's transmission. One of the air valves is used to operate a cylinder connected to the forward and reverse shift valves of the end loader power shift transmission while the other rotary air valve operates a pneumatic cylinder connected to the range selector valves of the power shift transmission. In this manner, both the bucket control functions as well as the forward and reverse movement of the end loader may be totally controlled by one hand of the operator leaving the other hand free to remain on the steering wheel at all times.Type: GrantFiled: February 6, 1979Date of Patent: May 19, 1981Inventors: Martin J. Spicer, Howard G. Spicer
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Patent number: 4240304Abstract: Valve operating system which is particularly suitable for use in the remote control of valves such as the function control valves of a crane or loading apparatus. The system includes output shafts for connection to the operating levers of the valves and input shafts disposed telescopically of the output shafts. A drive motor is connected to the input shafts for moving the same in unison along their axes, the detent means are provided for selectively locking the input and output shafts in each pair together. The detent means are operated by electrically energized solenoids which can be controlled remotely, e.g. from a hand held control unit connected to the remainder of the system by a cable.Type: GrantFiled: June 30, 1978Date of Patent: December 23, 1980Inventor: Edward E. Griffiths
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Patent number: 4237934Abstract: A vacuum flush water closet having a bowl and rim which are made from steel stampings covered with chemical resistant porcelain. The water closet has a self-contained flushing water and sewage valve discharge control system which is operatively mounted around the bowl and enclosed by an outer shroud made of a molded high impact plastic material. The water closet is shock proof and is mounted on a base plate that may be fixedly secured to a mounting surface, such as a floor or ship's deck. The bowl is mounted on a sewage discharge valve which is spring closed and vacuum opened. Flushing water is supplied through a spray ring mounted around the upper end of the bowl. The flushing water is controlled by a vacuum operated valve. The operation of the flushing water valve and the sewage discharge valve is controlled by a vacuum-gravity timer which is activated by a push button switch mounted at the rear of the bowl rim.Type: GrantFiled: July 28, 1978Date of Patent: December 9, 1980Assignee: Jered Brown Brothers, Inc.Inventors: Charles E. Gregory, Michael Brian, Jerald F. Thomas, James F. Cameron
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Patent number: 4237925Abstract: An anesthesia apparatus which comprises at least two flow meters, an oxygen gas supply means for supplying oxygen gas to one of said flow meters, a nitrous oxide gas supply means for supplying nitrous oxide gas to another one of said flow meters, at least two flow rate adjustment valves disposed between the one of said flow meters and said oxygen gas supply means and between said another one of said flow meters and said nitrous oxide gas supply means, respectively, each of said flow rate adjustment valve including a valve element having a predetermined shape to vary the rate of flow of each of said gases substantially in proportion to the amount of movement of said valve element, a flow control means connected to said flow rate adjustment valves for actuating said valves, and a flow rate adjustment means operatively connected to said flow control means and operative to set a selected angular position of said flow control means with respect to said flow rate adjustment valves for thereby determining the relatiType: GrantFiled: January 12, 1978Date of Patent: December 9, 1980Assignee: Citizen Watch Co., Ltd.Inventor: Yoshihisa Urushida
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Patent number: 4205705Abstract: Linkage which extends between right and left brake pedals and a valve construction provided with an outwardly extending shiftable shaft and a pair of valves disposed to either side of the shaft. A bolt assembly passes through one end of the shaft and mounts a yoke for rocking movement, the yoke having ends equally offset from the valves. Right and left substantially identical linkages are employed, each linkage including a push rod mounted for limited adjustable sliding movement in a trunnion carried by a bifurcated arm of a bell crank. The other bell crank arm is connected to an end of the yoke by a ball joint assembly, one end of a tubular intermediate portion being adapted to bear against a valve.Type: GrantFiled: June 30, 1978Date of Patent: June 3, 1980Assignee: Massey-Ferguson Inc.Inventor: Paul R. Chervenak
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Patent number: 4203471Abstract: Monitoring device for steam-turbine valves having respective electrohydraulic servocontrol devices for directly controlling the valves individually, including means for monitoring operability of the respective servocontrol devices, the operability monitoring means including means for comparing a value of a variable of each one of the servocontrol devices determining a setting of the respective valve with a mean value of corresponding variables of others of the servocontrol devices determining respective settings of valves associated with the other servocontrol devices and for establishing from the comparison if a permissible deviation from the mean value is exceeded by the variable value of the respective one of the servocontrol devices, and means for controlling a valve drive associated with the respective valve controlled by the respective one of the servocontrol devices for driving it in closing direction thereof when the permissible deviation from the mean value is exceeded.Type: GrantFiled: August 18, 1978Date of Patent: May 20, 1980Assignee: Kraftwerk Union AktiengesellschaftInventors: Ernst-Gunter Egener, Wolfgang Kindermann
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Patent number: 4194524Abstract: A system to flush the valve chamber of a valve (10) which is mounted in a flowline (12) by passing a cleaning fluid through the valve chamber when the valve is moved between open and closed positions. An actuator (38) operates a pair of flush valves (26, 32) which are connected to the valve body (14) for controlling the flow of the flushing fluid through the valve body. A flush control system is operated by movement of the flowline valve between the open and closed positions. The flush control system is connected to the actuator and operated when the flowline valve is moved from the open position to the closed position. The flush control system causes an operating fluid to be applied to the flush valve actuator so that the flush valves are opened to pass the flush or cleaning fluid through the valve chamber and then after a period of time again sequence the valve actuator to close the flush valves and terminate the cleaning of the valve chamber.Type: GrantFiled: May 22, 1978Date of Patent: March 25, 1980Assignee: ACF Industries, IncorporatedInventor: Charles H. Wicke
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Patent number: 4187704Abstract: A vault door lock of a combination type that operates on fluid pressure. The locking system has a master control valve assembly mounted on the rear face of the vault door and operatively associated with variously positionable dials mounted on the front face of the door and reciprocally mounted actuators which pass therethrough. A slave valve mounted on the rear face of the vault door is operated on command from the master control valve. A plurality of locking members are movably mounted on the vault door from one to another of a locking and unlocking position and coupled to the pistons of a piston cylinder assembly for moving the same. The master control valve consists of a plurality of operatively interrelated valves designed to provide an output that actuates the slave valve when such interrelated valves are actuated in a predetermined sequence. An alarm trigger is actuated by the master control valve when the operatively interrelated valves are actuated in a sequence other than the predetermined sequence.Type: GrantFiled: April 11, 1977Date of Patent: February 12, 1980Inventor: Spasoje Ristic-Petrovic
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Patent number: 4185652Abstract: A subaqueous sequence valve mechanism includes one or more main valves each adapted to be disposed in the water below the surface thereof. A first expansible chamber hydraulic actuator on the main valve operates that valve and also operates a second expansible chamber device against a spring. A hydraulic pressure line or lead from a controlled source above the surface is joined to and controls the submerged actuator. The second expansible chamber is connected in sequence through a throttle valve and a pressure relief valve to one side of a movable barrier in a hydraulic accumulator. On the other side of the movable barrier the accumulator is open to the water. There is also a return, one way flow valve shunting the pressure relief valve. The accumulator is hydraulically protected by a spring loaded check valve discharging into the water.Type: GrantFiled: October 31, 1977Date of Patent: January 29, 1980Assignee: NL Industries, Inc.Inventors: Howard Zintz, Richard C. Fisher, John F. Gee
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Patent number: 4135850Abstract: A fan assembly for a ventilator system. The assembly comprises a fan housing a inlet end and an outlet end. One or more blower wheels are secured for rotation in the fan housing to direct air from the inlet end to the outlet end. Each of the blower wheels has a plurality of inclined peripheral fan blades. Means is provided to support and impart a rotational drive to the blower wheels. An adjustable cylindrical damper is movably supported in closely spaced relationship to the periphery of the blower wheels to vary the quantity of fluid directed to the outlet end of the fan housing.Type: GrantFiled: September 7, 1976Date of Patent: January 23, 1979Assignee: Mark Hot Inc.Inventor: Marcel d'Anjou
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Patent number: 4078577Abstract: This disclosure relates to a hydrant coupling device including a pressure control valve which, due to its portability, may be connected to any one of a plurality of hydrants to regulate the flow of liquid therefrom, and additionally including a pit valve which is interlocked with the pressure control valve body to prevent the spilling of liquid if the control valve is accidentally forced loose from the pit valve.Type: GrantFiled: August 20, 1975Date of Patent: March 14, 1978Assignee: International Telephone and Telegraph CorporationInventor: Albert William Brown
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Patent number: 4055303Abstract: Disclosed are an aerial agrichemical spraying process and apparatus for producing and applying a multifluid invert emulsion. The apparatus, which is combined with an aircraft, comprises automatically balanced concentric tanks; multifluid valves combining individual preset metering control for each fluid with common, automatic, and simultaneous on/off control for all fluids; a single low-speed pump; a rotary twisted blade in-line mixer; a boom fitted with a number of spray nozzles; feeding and linking conduits; and an electrical control system.Type: GrantFiled: February 5, 1976Date of Patent: October 25, 1977Assignee: Golden State Helicopter, Inc.Inventor: Erben G. Brown
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Patent number: 4054083Abstract: A dual lever control mechanism is disclosed for actuating a pair of control devices individually having first and second modes of operation, including a stationary support, a first lever arrangement pivotally mounted on the support for selectively moving both of the control devices into either their first modes of operation or their second modes of operation for effecting simultaneous coordinated movement thereof, and a second lever arrangement pivotally mounted on the support and cooperatively coupled with a portion of the first lever arrangement for selectively moving both of the control devices respectively into either their first and second modes of operation or their second and first modes of operation for effecting simultaneously opposite coordinated movement thereof.Type: GrantFiled: July 14, 1975Date of Patent: October 18, 1977Assignee: Caterpillar Tractor Co.Inventor: Robert Eugene Utter
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Patent number: 4051860Abstract: A valve control mechanism for operating a plurality of valves in a bank of valves which can be selectively operated by interchangeable lever arrangements one of which has a separate lever for each valve and another of which has a single lever for a pair of valves. The bank of valves and the lever arrangements are detachably removable independently of each other to permit easy servicing and selecting of the desired lever arrangement or to change the sequence of valve operation.Type: GrantFiled: December 15, 1975Date of Patent: October 4, 1977Assignee: Massey-Ferguson Inc.Inventors: Allyn C. Dowd, Habibur Rahman
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Patent number: 3993100Abstract: A hydraulic control system for controlling a plurality of remotely positioned hydraulically actuated underwater devices by a single hydraulic control line extending underwater. A reference hydraulic manifold is connected to the single control line and a signal hydraulic manifold is connected to the single control line. A pilot actuated hydraulic control valve is connected to each of the underwater devices controlling the flow of actuating fluid thereto. The pilot of each valve is connected to both the reference manifold and the signal manifold, but the pilot of each of the valves is actuated by different pressure levels in the signal manifold whereby the underwater devices may be controlled in a predetermined sequence by applying predetermined pressure levels to the single hydraulic control line. A pressure regulator is positioned in the control line upstream of the reference manifold to maintain the reference manifold at a predetermined pressure level.Type: GrantFiled: April 28, 1975Date of Patent: November 23, 1976Assignee: Stewart & Stevenson Oiltools, Inc.Inventors: Terry W. Pollard, David P. Herd, Jack Whiteman
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Patent number: 3973594Abstract: A mixing valve for hot and cold water has two control levers for single hand operation each governing the position of a valve plug. The one lever controls the flow rate of the hot water and the other the flow rate of the cold water. The temperature of the mixed water is regulated by change of the relative positions of the levers and its flow rate is controlled by movement of the levers in unison. Such movement will leave the temperature unaffected because the levers actuate the plugs over cam means and the control surfaces between those means and the plugs yield a logarithmic relationship between the flow area at each plug and the corresponding lever movement.Type: GrantFiled: December 30, 1974Date of Patent: August 10, 1976Assignee: IFO ABInventors: John Harry Gustafsson, Tord Egron Henry Froberg
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Patent number: 3963051Abstract: A remote control system for the jack cylinders of a hydraulically operated crane includes a plurality of regulating valves for controlling respective jack cylinders, the regulation of each valve being controlled by the movement of a respective valve spool connected to a respective lever forming part of a linkage including an arm mounted on a rotatable shaft and connectable to the shaft by a respective electromagnetically operated clutch so that by engagement of one said clutch and rotation of the shaft to a predetermined position the corresponding valve spool may be correspondingly positioned to move the associated jack cylinder accordingly.Engagement of the clutches and rotation of the shaft can be controlled by a portable actuating unit connected to the rest of the system by an electrical cable, the system including a control means which adjusts the position of the shaft to correspond with the setting of a control member on the actuating unit.Type: GrantFiled: August 16, 1974Date of Patent: June 15, 1976Assignee: Kuhlmann & Rust KG, MaschinenfabrikInventor: Hans-Jochen Kuhlmann
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Patent number: 3958597Abstract: A throttle control that provides accurate and reliable control for a plurty of remote air driven devices. The throttle control employs a plurality of primary valves that are built into a common body with a handle and a plurality of operating levers. The body has a single air supply port which directs air through a common chamber to all of the primary valves. In the body are formed a plurality of separate chambers that communicate the outlet air from the plurality of respective primary valves to the plurality of air conduits to supply air to the respective air driven devices. The handle has a chamber through which exhaust air has a tortious flow path to atmosphere. Each primary valve employs an air control valve and an air vent valve that are sequentially actuated by the associated operating lever. When the lever is not depressed, the control valve is closed and the vent valve is open and vents the air in the supply conduit through the handle chamber to atmosphere.Type: GrantFiled: October 21, 1974Date of Patent: May 25, 1976Assignee: The United States of America as represented by the Secretary of the NavyInventors: Robert W. Meyer, Richard I. Schrick
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Patent number: 3937254Abstract: A device for monitoring the relative position of synchronously moved valve cases in safety valves controlling pneumatic or hydraulic drives. Fixedly attached to each valve case and symmetrically disposed one to the other is a member of a metallic material, arranged proximate to the free ends of a pivotally mounted magnetic bar. The axis of rotation of the magnetic bar, which is aligned with the synchronous position of the valve cases in its basic position, is parallel to the direction of movement of the valve cases, and a swing of the magnetic bar, which only occurs in the event of a defect, i.e. if the valve cases do not operate in synchronism, provides a signal for making the monitored drive inoperative.Type: GrantFiled: March 4, 1974Date of Patent: February 10, 1976Assignee: Concordia Fluidtechnik GmbH SteuergerateInventor: Kurt Stahle