Pressure Patents (Class 116/266)
  • Patent number: 5078078
    Abstract: A warning indicator provides an indication that a transient over-pressure condition has occurred in a transformer. The indicator takes into account small or slow pressure changes and only indicates pressure surges. The internal arcing warning indicator comprises an opening in a casing of a transformer, a movable piston over the opening with a retainer to retain the piston over the opening, the piston having at least one small aperture therein to allow slow increases and decreases of pressure within the transformer without the piston moving, and an indicator attached to the piston, the indicator providing an indication that the piston has moved a predetermined distance and retaining the indication until reset.
    Type: Grant
    Filed: December 21, 1990
    Date of Patent: January 7, 1992
    Assignee: Powertech Labs Inc.
    Inventor: Nikola Cuk
  • Patent number: 5014786
    Abstract: A pressure checker for a fluid pressure source, including a main unit which includes/comprises a hollow portion which can communicate with a fluid pressure source, a cap with a window fitted on the main unit, a spool contained in the hollow portion of the main unit to be reciprocal, said spool being provided with a front end portion with a defined pressure indication surface, a compression coil spring for biasing the spool against the pressure of the fluid pressure source, and a flat light-shielding member positioned in the window of the cap, said flat light-shielding member being provided with a bag made of a material which allows at least partial transmission of light, and a light-absorbing liquid sealed in the bag, wherein the flat light-shielding member transmits light through the window toward the defined pressure indication surface when the spool is moved by the pressure of the fluid pressure source against the biasing force of the compression coil spring, and can also transmit light reflected by the de
    Type: Grant
    Filed: March 5, 1990
    Date of Patent: May 14, 1991
    Assignee: Nitto Kohku Co., Ltd.
    Inventor: Yoshikazu Kobayashi
  • Patent number: 4978947
    Abstract: A rupturable fluid flow indicator and a rupture disk assembly including the indicator are provided. The indicator is comprised of a rupturable member adapted to be clamped across a fluid flow passageway having at least one opening formed therein for weakening a portion of the member. An electric current conductor adapted to be electrically connected in an alarm circuit is attached across the weakened portion of the rupturable member whereby when the member ruptures as a result of fluid pressure exerted thereon, the conductor also ruptures.
    Type: Grant
    Filed: May 25, 1989
    Date of Patent: December 18, 1990
    Assignee: BS&B Safety Systems, Inc.
    Inventor: Michael C. Finnegan
  • Patent number: 4969492
    Abstract: The method for filling a soft, flexible, thin-walled inflatable bladder with a fluid medium to a predetermined extent that comprises; folding a portion of the soft, flexible, thin-wall of the bladder and engaging the fold in predetermined pressure engagement between opposing clamping surfaces of a clamping device and thereafter introducing fluid medium into the bladder to fill it. The fold slides from engagement between the surfaces when the tensile forces directed onto and through the wall by the fluid medium delivered into the bladder exceed the holding force exerted by the clamping device.
    Type: Grant
    Filed: September 25, 1989
    Date of Patent: November 13, 1990
    Inventor: George R. Monzo
  • Patent number: 4951697
    Abstract: The present invention provides apparatus for visually indicating the failure of a rupture disc comprised of an elongated hollow body member, a piston disposed in the body member which is moved therein by pressurized fluid pressure exerted thereon, and an elongated indicator pin which is pushed by the piston through an opening in the body when pressurized fluid causes the piston to be moved therein. The body member includes a pressurized fluid exhaust port which is opened by the movement of the piston. Pressurized fluid exhausted through the exhaust port can be vented to prevent abnormal rupture disk operation or it can be utilized to activate an alarm.
    Type: Grant
    Filed: November 27, 1989
    Date of Patent: August 28, 1990
    Assignee: BS&B Safety Systems, Inc.
    Inventor: Donald K. Fritts
  • Patent number: 4899684
    Abstract: The invention relates to the inspection of pressure attained in bottles with beverages, especially sparkling wines, by providing a pressure indicator and a deformation member in the carrier stopper body. In the body is provided a movable pressure indicator (2) while between the carrier body (1) and the indicator (2) there is interposed at least one deformation member (3) for influencing the magnitude of an indicator position change relative to the position of the body (1).
    Type: Grant
    Filed: August 17, 1988
    Date of Patent: February 13, 1990
    Assignee: Jednotne Rolnicke Druzstvo Jedlova Vo Vysnej Jedlovej
    Inventors: Vladimir Houzvic, Jiri Jakl
  • Patent number: 4875509
    Abstract: An air pressure control system for verifying and adjusting air pressure, simultaneously, in a pair of vehicle tires, either the pair of front tires or the pair of rear tires or any individual tire. The system comprises a pair of air conduits having tire valve connectors at a free end thereof for connecting the conduits to respective one of a pair of vehicle tires. The conduits are interconnected together at a junction to equilibrate air pressure in the pair of tires. An air pressure source is also provided. A valve connects the air pressure source to the junction, in an inflating mode, to inflate the tires. Another valve also connects the junction to outside atmosphere, in a deflating mode, to evacuate air from the tires. A pressure sensor is connected in association with the valves and the junction to display the air pressure equilibrated between the pair of tires. A display device visually indicates the equilibrated pressure at the junction to determine if the valves should be actuated and in which mode.
    Type: Grant
    Filed: February 16, 1988
    Date of Patent: October 24, 1989
    Assignee: E.R.C.D. Industries Inc.
    Inventor: Jean Da Silva
  • Patent number: 4869197
    Abstract: A method and device for indicating the swelling of a casing or the like having a wall with at least one generally planar portion prone to deformation by pressure buildup within the casing. The device comprises an elongate strip of visible frangible material adapted for spanning superposition with the planar portion of the wall and means for securing opposing ends of the frangible strip to the casing to restrict movement of the ends perpendicular to the planar portion of the wall. Increasing bulging of the wall deflects the frangible strip to the point of fracture thereof. In another embodiment, gaskets may be interposed between the ends of the frangible strip and the wall of the casing to provide a clearance therebetween, thus increasing the permissible degree of bulging of the wall which may occur before deflection of the frangible strip.
    Type: Grant
    Filed: February 23, 1988
    Date of Patent: September 26, 1989
    Inventors: Bal K. Gupta, David L. Mader
  • Patent number: 4831957
    Abstract: Three concentric hollow cylinders, with radii for slidably loose interfitting, are coaxially assembled against separation and partially sealed by a combination slotted seal and detent, for telescoping outwardly when actuated by exhaust pressure from a sensing device to expose a formerly hidden strip on one of the cylinder sides, and then to open a passage to prevent back pressure from affecting the sensing device. The partial sealing prevents slight leakage of exhaust pressure from outwardly telescoping the cylinders. The expansion of the slotted seal and detent when not compressed by telescoping cylinders engages resetting cylinder edges that are rounded. The detent is operable to prevent resetting but is overridable manually, the slotted seal and detent being recompressable by the rounded surfaces engagement without damage.
    Type: Grant
    Filed: June 2, 1986
    Date of Patent: May 23, 1989
    Inventor: Kip B. Goans
  • Patent number: 4785670
    Abstract: A compact pressure gauge includes a cylinder which has a compressed gas inlet, a piston, a U-shaped piston rod, and a compression spring. The compression spring is sleeved on the piston rod in the cylinder for biasing the piston against the compressed gas pressure exerted on the piston. The U-shaped piston rod has parallel first and second arms. The first arm extends into the cylinder. The second arm includes a rack secured thereto. A rotating shaft includes an indicator secured thereto for displaying the rotational degree of the rotating shaft, and a pinion secured to the rotating shaft for meshing with the rack. A channel member is secured to the cylinder and has a guide slot through which the second arm extends. A positioning plate is secured to the channel member so that the rotating shaft is journalled on the cylinder and the positioning plate. When the piston rod is moved, the rotating shaft is rotated due to the fact that the pinion always meshs with the rack.
    Type: Grant
    Filed: March 1, 1988
    Date of Patent: November 22, 1988
    Inventor: Ten T. Hwang
  • Patent number: 4722451
    Abstract: Vacuum containers of synthetic polymeric resins include a wall portion deformable under vacuum containing conditions, to give a visual indication of the vacuum integrity. The containers by virtue of the deformable portion resist paneling.
    Type: Grant
    Filed: August 22, 1986
    Date of Patent: February 2, 1988
    Assignee: General Electric Company
    Inventor: George R. Conrad
  • Patent number: 4654643
    Abstract: By providing a pressure responsive actuator in controlled actuating engagement with a latch mechanism in which a spring-loaded indicator is securely retained, with said indicator being movable from a non-visible, retained position to a visible, released position in response to pressure exceeding a desired level, a unique, precision constructed pressure sensor and indicator is achieved. In the preferred embodiment, the latch mechanism comprises a plurality of elongated, resilient, spring-biased locking fingers, with the locking fingers being controllably disengaged from the indicator in response to the movement of the pressure responsive actuator. In addition, the present invention is also quickly and easily manually reset, thereby further enhancing the usability of the present invention.
    Type: Grant
    Filed: July 22, 1985
    Date of Patent: March 31, 1987
    Inventor: Daniel T. Meisenheimer, Jr.
  • Patent number: 4619328
    Abstract: A discharge valve assembly for a fire extinguisher container includes a housing defining a passageway providing communication between the container outlet and a nozzle. An elongated tubular valve stem is axially movable in the passageway between open and closed conditions with respect to a valve seat in the passageway, the stem projecting from the passageway for engagement by an actuating lever. An elongated indicating rod, shorter than the valve stem, is coaxially movable therein between extended and retracted conditions. A bias spring and the pressure in the container holds the valve stem closed, and the pressure in the container holds the indicating rod extended. A bias spring urges the indicating rod toward a retracted position. To check the pressure the indicating rod is manually depressed, the extent to which it returns to its extended condition being indicative of the magnitude of the pressure in the container.
    Type: Grant
    Filed: November 28, 1984
    Date of Patent: October 28, 1986
    Assignee: Pittway Corporation
    Inventors: Gerard Seyler, Donald R. Sloan
  • Patent number: 4601254
    Abstract: A tire pressure warning device is disclosed which produces an explosive report when the tire pressure falls below a predetermined value. The device includes a connector member which screws onto the valve stem of a tire and admits pressurized air from the tire to a pressure sensing valve. A cap member screws onto the connector member and includes an actuating plunger which is biased by a coil spring toward engagement with a valve actuator in the connector member. The cap member has an outlet passage which is closed by an elastomeric balloon. A closure valve which is normally open is adapted to close the outlet passage. When the tire pressure falls below a predetermined value, the pressure sensing valve is opened and pressurized air from the tire is admitted through the closure valve to the balloon and the balloon is inflated until it explodes. The outrush of air following explosion of the balloon causes the closure valve to close and prevent further loss of air from the tire.
    Type: Grant
    Filed: March 24, 1983
    Date of Patent: July 22, 1986
    Inventors: Chung-Siung Huang, Hsien-Ching Kuo
  • Patent number: 4438792
    Abstract: Pressure relief detecting/alert apparatus for detecting the activation of pressure relief devices associated with fluid storage is disclosed comprising a cover adapted to move in response to a release of stored fluid, a tube assembly for containing a control fluid under pressure and capable of rupture upon movement of the cover, and means for detecting a decrease in control fluid pressure.
    Type: Grant
    Filed: December 28, 1981
    Date of Patent: March 27, 1984
    Assignee: Air Products and Chemicals, Inc.
    Inventor: George A. Timberlake, Jr.
  • Patent number: 4432462
    Abstract: A reliable and low cost indicator to be associated with a receptacle filled with dosage forms (e.g. over-the-counter drugs) and a corresponding method by which to quickly and easily warn a consumer that an unauthorized tampering may have occurred to the receptacle and the contents thereof. The tampering indicator is preferably either attached to or integrally formed with a seal at the underside of a removable receptacle cap. The tampering indicator comprises a fluid filled reservoir, a tab having a chemically treated indicator strip thereat, and a fluid path by which fluid from the reservoir communicates with the indicator strip. The indicator is engaged by the rim of the receptacle when the cap is positioned thereover by the dosage form manufacturer. Accordingly, fluid is forced from the reservoir into the fluid path. However, the fluid path is initially blocked at the engagement thereof by the receptacle rim.
    Type: Grant
    Filed: October 18, 1982
    Date of Patent: February 21, 1984
    Inventor: Randall A. Newkirk
  • Patent number: 4404924
    Abstract: A medical suction device is disclosed which includes a vacuum indicator flag. This flag is made up of a flexible tube capped with a plug. The rigidity of the walls of the tube is chosen such that the walls collapse when the pressure inside the tube falls below a predetermined value, thereby allowing the flag to droop. In addition the rigidity of the tube serves to hold the flag upright when the pressure inside the tube rises above a second predetermined value. Thus the state of the flag (upright or drooped) provides a remote indication of the pressure being developed by the suction device. In addition, the suction device uses a constant force coiled ribbon spring to provide substantially constant suction as the suction device is filled. Furthermore, the suction device includes a plurality of separately valved drainage receptacles which can be folded and stored compactly against the drainage device.
    Type: Grant
    Filed: September 5, 1980
    Date of Patent: September 20, 1983
    Assignee: UreSil Company
    Inventors: Edward M. Goldberg, Seymour Bazell
  • Patent number: 4375789
    Abstract: Control system for indicating which, of a plurality of sensed functions, first malfunctions. The system includes a plurality of series connected devices, each such device includes a shiftable valve which, in one position activates an indicator, and, in another position deactivates said indicator. Signalling connections link the devices such that all indicators, save the one governing the first malfunction, remain in the indicating condition they were in prior to such malfunction occurring.
    Type: Grant
    Filed: August 7, 1980
    Date of Patent: March 8, 1983
    Assignee: B.W.B. Controls, Inc.
    Inventor: Ned A. Bergeron
  • Patent number: 4362121
    Abstract: The invention provides a deflation warning device for a pneumatic tire which gives a clear, positive indication of a predetermined pressure loss by the exposure of a brightly colored element within a transparent dome, all moving parts of the device being fully enclosed and protected against the ingress of dirt and corrosion by a housing.The element is either masked or unmasked by an opaque shield mounted on a piston which is biased by a spring to unmask the element but can be displaced by tire pressure acting on its surface to mask the element.In preferred embodiments of the invention the piston is located between the inner and outer parts of a second piston which is in turn responsive to tire pressure acting on its upper surface.
    Type: Grant
    Filed: August 8, 1980
    Date of Patent: December 7, 1982
    Assignee: Dunlop Limited
    Inventor: Philip H. Pegram
  • Patent number: 4361107
    Abstract: A pressure indicating device for use with medical cannulae having balloon type sealing cuffs such as tracheal tubes. The device would be added to a normal pilot balloon to indicate having exceeded a preset pressure by having a long tubular structure that could be folded inside itself telescopically at low pressure and would pop-out at the preset pressure. When elongated or popped-out, a visual indicator would be exposed until the overpressure was corrected and the tube again tucked into itself.
    Type: Grant
    Filed: November 20, 1980
    Date of Patent: November 30, 1982
    Inventor: Gordon A. Gereg
  • Patent number: 4361048
    Abstract: A pointer instrument movement is disclosed including a chassis of integrally moulded plastic, a pointer shaft rotatably mounted on the chassis, a lifting member, a measured value pickup which converts changes of the measured quantity to a mechanical deflection, a measured value transducer having a rocker connected to said lifting member for converting the mechanical deflection of the measured value pickup into a rotation of the pointer shaft, the rocker being formed integrally with said chassis.
    Type: Grant
    Filed: December 8, 1980
    Date of Patent: November 30, 1982
    Assignee: Helmut Bernhardt GmbH u. Co. KG
    Inventor: Johann Huttinger
  • Patent number: 4295566
    Abstract: An evacuated article-containing package assembly with a vacuum integrity indicator comprises an air-impervious package having an access opening and having at least a flexible portion. An article is included inside the package. A member is included inside the package which is compressible under the influence of pressure less than atmospheric pressure. A closure seal is on the package for sealing the access opening, with the sealed package being air-evacuated. The compressible member is adapted to expand against the flexible portion of the package to outwardly expand the flexible portion if the pressure inside the package equalizes with the pressure outside the package. When this occurs, the expanded flexible portion serves as a visual indicator that there is no vacuum condition inside the package.
    Type: Grant
    Filed: May 7, 1980
    Date of Patent: October 20, 1981
    Assignee: Becton, Dickinson and Company
    Inventor: Robert C. Vincek
  • Patent number: 4252076
    Abstract: An automatic signaling device responsive to small pressure variation, said pressure variations being created by a restriction of fluid flow within a flow system. The pressure variation causes fluid to flow through a resonant; loading chamber, activating a longitudinal wave resonator. The generation of longitudinal waves is apparent by the production of an audible signal. The device is mounted to the flow system using attaching means designed as part of or appurtenant to the device. In some embodiments the dimensions of the respective components of the device are adjustable.
    Type: Grant
    Filed: December 20, 1978
    Date of Patent: February 24, 1981
    Inventor: Douglas J. Williams
  • Patent number: 4246864
    Abstract: A device for indicating airtightness of a packing for apparatus which is to be stored under a vacuum and, particularly for protective breathing apparatus, comprises, a packing enclosing a packing space in which the apparatus is stored which has an outer surface with a recessed portion forming a chamber having a cover overlying the chamber enclosing and sealing it. A hollow expansible and retractable member, such as a bellows, is mounted in the chamber and has an opening to its interior extending through the packing into the interior of the packing space so that the pressure inside of the bellows is the same as the packing space. A ball is disposed between the bellows and the cover and it is held by expansion of the bellows against it in a fixed position which indicates an increase of the pressure within the packing beyond a predetermined amount.
    Type: Grant
    Filed: May 9, 1979
    Date of Patent: January 27, 1981
    Assignee: Dragerwerk Aktiengesellschaft
    Inventor: Adalbert Pasternack
  • Patent number: 4209041
    Abstract: A hydraulic pressure responsive accessory, such as a cavitation eliminator, for a hydraulic system and a replacement bladder assembly for the accessory. The accessory comprises a cartridge having an inlet for connection to a hydraulic system, and contains a gas filled flexible bladder which compresses and expands in response to pressure fluctuations in the system. This bladder is removably secured within the cartridge in a unique way which permits easy removal of a bladder in the field when worn and replacement of the bladder by that of the present replacement bladder assembly. Shield means are provided between the bladder and a grid overlying casing inlet openings to protect the bladder from impact damage, and means connected with the shield provide indication of excess bladder pressure or automatic release of excess pressure.
    Type: Grant
    Filed: March 27, 1978
    Date of Patent: June 24, 1980
    Inventor: Ernest W. Loukonen
  • Patent number: 4190014
    Abstract: In an industrial dust collector comprising a gas intake dirty air chamber, a filtration clean air chamber, and a set of fabric filter bags mounted within the filtration chamber with the bag interiors in fluid communication with the gas intake chamber having a system for cleaning the filtration chamber which includes a venturi in fluid communication with both chambers to effect cleaning of the collector. A method of cleaning the filtration chamber of an industrial dust collector having fabric filter bags mounted within a filtration chamber with the bag interiors in fluid communication with a gas intake chamber is disclosed comprising the steps of evacuating dust from the filtration chamber and directing the evacuated dust into the gas intake chamber.
    Type: Grant
    Filed: June 19, 1978
    Date of Patent: February 26, 1980
    Inventors: Hugh N. Jenkins, Robert P. Black
  • Patent number: 4184376
    Abstract: A device (10) for metering discrete lengths of filament utilized in a flexible filament vegetation cutting device is disclosed. The line metering device (10) is preferably used in flexible filament lawn mowers. An electric motor (28) rotatively drives a drive shaft (32) about its axis. A driving mechanism, preferably a spool (36) is coupled to the drive shaft (32) for rotation therewith whenever the drive shaft (32) is rotated. A driven mechanism, preferably a guide drum (84), is selectively coupled for rotation to the driving mechanism (36). The spool (36) has the flexible filament (66) wound about it and is coupled to one of the driven and driving mechanisms (84, 32) for rotation therewith.
    Type: Grant
    Filed: December 13, 1978
    Date of Patent: January 22, 1980
    Assignee: Donaldson Company, Inc.
    Inventors: Timothy J. Thomas, Harold A. Manguson
  • Patent number: 4178939
    Abstract: Apparatus for visually indicating the degree of inflation of an inflatable cuff surrounding a catheter which is adapted to be inserted into a body passageway. The apparatus comprises a hollow-walled tubular member formed with a plurality of ridges and valleys and is selectively inflatable into a balloon-like shape in response to the pressure of air applied to the cuff by means of a passageway extending into the tubular member. The member is collapsible without occluding the fluid passageway extending into the indicator apparatus and thus without preventing the deflation of the cuff.
    Type: Grant
    Filed: September 29, 1977
    Date of Patent: December 18, 1979
    Assignee: Portex, Inc.
    Inventor: Thomas P. Stephens
  • Patent number: 4174673
    Abstract: A low pressure warning cap for a pneumatic tire air valve including a generally cylindrical body having first and second ends, a cylinder adjacent the first end, a threaded connector for attachment to a conventional air valve stem of a pneumatic tire at the second end and an acting chamber connecting with and disposed intermediate the cylinder and the threaded connector, a piston disposed in the cylinder and resiliently biased toward the acting chamber, the cylinder having an opening at the first end, a deformable diaphragm disposed across the acting chamber between the threaded connector and the enlarged end, a perforated diaphragm disposed across the cylinder adjacent the opening, an elastic sack enveloping in air tight manner the first end including the opening, and a protuberance in the threaded connector to cooperate with the valve to open the valve upon attachment of the cap to valve, whereby, at a desired tire pressure, the deformable diaphragm is deformed by air from at the desired pressure to move th
    Type: Grant
    Filed: April 6, 1978
    Date of Patent: November 20, 1979
    Inventors: Wei-Ling Tung, Steven Kwan
  • Patent number: 4168493
    Abstract: An alarm system for a multi-facet functional installation in which a malfunction in any segment of the installation will result in the initiation of an audio alarm signal of such a character as to immediately indicate the relative severity of the malfunction.
    Type: Grant
    Filed: October 20, 1977
    Date of Patent: September 18, 1979
    Assignee: Texaco Inc.
    Inventor: Rocky R. Romero
  • Patent number: 4166429
    Abstract: Disclosed herein is a fluid pressure indicator for providing visual indication of the magnitude of a fluid pressure condition. The indicator comprises an optical element including a front surface for receiving ambient light and a rear, light-reflecting portion having three mutually perpendicular surfaces which define a cube corner having an apex remote from the front surface, and a one-piece, resilient, imperforate diaphragm in cooperative relationship with the rear, light-reflecting portion of the optical element, to provide a chamber between the interior of the diaphragm and the three perpendicular surfaces. The diaphragm is normally not in optical engagement with the three perpendicular surfaces, but is resiliently deformed into such optical engagement upon the application of a positive fluid pressure differential to the exterior of the diaphragm.
    Type: Grant
    Filed: September 14, 1977
    Date of Patent: September 4, 1979
    Assignee: Amerace Corporation
    Inventor: Adam Smorzaniuk
  • Patent number: 4166430
    Abstract: Disclosed herein is a fluid pressure indicator for providing visual indication of the magnitude of a fluid pressure condition. The indicator comprises an optical element including a front surface for receiving ambient light and a rear, light-reflecting portion having three mutually perpendicular surfaces which define a cube corner having an apex remote from the front surface, and a one-piece, resilient, imperforate diaphragm in cooperative relationship with the rear, light-reflecting portion of the optical element, to provide a chamber between the interior of the diaphragm and the three perpendicular surfaces. The diaphragm is normally not in optical engagement with the three perpendicular surfaces, but is resiliently deformed into such optical engagement upon the application of a positive fluid pressure differential to the exterior of the diaphragm.
    Type: Grant
    Filed: September 14, 1977
    Date of Patent: September 4, 1979
    Assignee: Amerace Corporation
    Inventor: Glenn W. Johnson, Jr.
  • Patent number: 4143616
    Abstract: A selectively changeable pneumatic control system for monitoring the start-up and running of process machinery, the system having a pneumatically operated indicator, a pneumatically operated arrangement for operating the indicator and a selector for setting the pneumatically operated arrangement to any one of a first, second, third, fourth or fifth monitoring condition thereof which monitors a respective variable of the process machinery and will operate the indicator to indicate an unsafe condition thereof, the first condition being adapted to monitor a variable of the process machinery that is normally safe when the process machinery is not running, the second condition being adapted to monitor a variable of the process machinery that is normally unsafe when the process machinery is not running but must be locked out to allow start-up and must become safe within a predetermined time period after initial start-up, the third condition being adapted to monitor a variable of the process machinery that is normal
    Type: Grant
    Filed: February 24, 1978
    Date of Patent: March 13, 1979
    Assignee: Robertshaw Controls Company
    Inventor: Harley V. Bible
  • Patent number: 4137942
    Abstract: A control valve structure and combined visual indicator for controlling fluid and visually indicating the operating condition of a portion of a fluid system. The control valve has a slide valve mounted in a housing and biased toward a retracted position with one end portion thereof extending from the housing. The extended end portion of the slide valve has a knob adapted to be manually gripped for moving of the slide valve outwardly for setting same. A visual indicator is mounted on the knob. A port in the housing communicates with the slide valve to permit the application of fluid pressure to the slide valve to move same outwardly. The visual indicator has a visually observable indicator member movable between two positions for indicating the presence of either of two associated conditions in a system containing the control valve.
    Type: Grant
    Filed: July 15, 1976
    Date of Patent: February 6, 1979
    Assignee: W-K-M Wellhead Systems, Inc.
    Inventors: Melvin J. Hargraves, Clifford M. Peters