Abstract: The disclosure relates to a pressure sensitive indicating device of extremely simplified nature, providing a visual indication of a predetermined pressure threshold level. A typical and advantageous form of the device is a valve or valve extension member for a pneumatic tire, providing a visual indication of the existence or not of a desired pressure level. The device, in its most basic form, comprises an element formed of a natural or synthetic deformable elastomer, designed to expand upon exposure to increasing pressure levels. A covering element is associated with the deformable elastomer and is displaced by distention of the elastomer. By providing the deformable elastomer in a distinctively different color than the cover element, the displacement of the cover upon pressurization to a desired threshold, is readily evident to the observer.

Abstract: A visual tire valve is adapted for mounting over a tire valve stem and includes an apertured stem housing at one end mounted upon the valve stem, has an elongated bore intermediate its ends, a barrel having a counterbore, and a stem member at its other end having a normally closed longitudinal bore whose inner end communicates with the counterbore and whose outer end communicates with atmosphere. An axially apertured bolt is slidably nested within the elongated bore and has three annular bands of different colors upon its exterior for indicating over inflation, proper inflation and under inflation with respect to a window in the stem housing. A spring is interposed in compression between the bolt and stem member. A normally seated spring-biased air flow control rod is disposed within the stem member closing off air communication therethrough. A normally seated valve within the bolt is adapted to prevent passage of air therethrough in one direction.

Abstract: A mounting device is provided for mounting a low tire pressure sensor of known type, which may include a deflectable finger and a self-contained and powered ratio transmitter, on the tire rim of a vehicle wheel. The mounting device consists of three simple coordinated metal strapping, strapping seal and counterweight components. The seal is mounted on the counterweight. To install the mounting device, the strapping is engaged with the sensor and ends of the strapping are overlapped and sealed by the seal. To complete the installation the strapping is tensioned around the wheel rim by strapping and sealing tools. When installed, the strapping holds the sensor and counterweight in predetermined fixed positions on the rim within a tire mounted on the rim at all reasonable wheel speeds.

Abstract: A low tire pressure sensor for emitting a magnetic signal when the tire pressure reaches a low limit pressure includes a signal device having a magnet movable from a storage position to an actuated position by tire pressure applied to the magnet from an air switch. The air switch includes a bellows charged to a reference pressure and exposed to tire pressure for moving in response to tire pressure changes, and a three-way valve operated by the bellows for venting the signal device to atmospheric pressure when the tire pressure is normal and for closing the vent and applying tire pressure to the signal device to actuate it when the pressure drops below a preset low pressure.

Abstract: An air switch responsive to low tire pressure for emitting a pulse of air when a critical low tire pressure is achieved comprises a housing having a chamber ported to the internal tire pressure and a bellows within the chamber filled to a reference pressure. A passageway connecting the chamber to an outlet port is closed by a spring biased poppet valve. A pin on the moving end of the bellows is arranged to extend through the passageway to abut the poppet valve so that when low tire pressure causes bellows expansion, the pin will unseat the poppet valve to allow air pressure to escape from the tire through the outlet port. A second valve surrounding the stem on the bellows engages the chamber end of the passageway to close the same whenever the tire pressure reaches a second critical low pressure to stop the airflow through the outlet port.

Abstract: A rubber tired transportation vehicle for use in a mass transit system is provided with a disc member positioned adjacent to at least one vehicle support pneumatic tire operative with a condition sensing apparatus to detect the occurrence of a flat tire condition and to limit the vehicle axle drop in the event of a resulting loss of desired vehicle support because of that flat tire condition.

Abstract: A visual tire valve is adapted for mounting over a tire valve stem and includes a stem housing at one end mounted upon said valve stem, has an elongated bore intermediate its ends and an exteriorly threaded barrel at its other end having a counter bore. An axially apertured bolt is slidably nested within said bore and has three annular bands of different colors upon its exterior for indicating over inflation, proper inflation and under inflation with respect to a window in said stem housing. A second housing having an internally threaded bore is adjustably mounted upon and along said barrel and supports therein a stem having a normally closed longitudinal bore whose inner end extends into the second housing bore and partly into said counter bore and whose outer end projects from the second housing. A spring is interposed in compression between said bolt and stem. A normally seated spring-biased air flow control rod is disposed within said stem closing off air communication therethrough.

Abstract: A method and apparatus are provided for monitoring tire pressure for motor vehicles, or the like, in which coded sound signals emitted from a wheel-mounted sound signal generator are detected and processed. The coded signal from the generator serves to distinguish the sound signal from background noise. The output of the generator is comprised of at least two coherent frequencies that beat acoustically with one another to produce an amplitude modulated sound signal that is then detected by a transducer which converts the sound signals into the electrical signals. The electrical signals are then fed through the processing circuitry including a detector which extracts the modulation envelope and applies it to an audio band-pass filter. The filter accepts the envelope within a predetermined frequency range, eliminating all signals which are not within the designed band pass. A second detector converts the audio signal to a DC level and feeds it to a threshold comparator.

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

Abstract: A low pressure, tread wear and speed indicator for a tire includes at least one abutment member secured to the exterior surface of one of the sidewalls of the tire adjacent to the tread, which projects laterally outward from the sidewall. The abutment member is positioned at a distance radially inwardly from the tread such that, upon tire deflation or excessive tread wear or a combination thereof, the abutment will strike the road surface during vehicle operation, to produce a vibrational and/or audible signal perceivable by the driver, indicating an unsafe tire condition. The indicator may also include a weighted insert embedded within the abutment member which, upon operation of the vehicle at an excessive or illegal rate of speed, will produce an eccentric tire condition which, in turn, causes a vibrational signal. A tire deflation indicator which includes a segmented radially-extending rib formed on the interior surface of the tire sidewall is also provided.

Abstract: An acoustic alarm arrangement associatable with a pneumatic tire for generating a signal indicating that pressure of gas in the tire decreases from a predetermined magnitude, has a housing arranged to be connected with a tire and bounding an inner chamber, a signal element associated with the housing and actuated under the action of a strike, and a striking element movable in the inner chamber between an inoperative position in which it is spaced from the signal element and an operative position in which it approaches and strikes the latter. The striking element subdivides the inner chamber into a first compartment communicating with the interior of the tire, and a second compartment.

Abstract: A warning indicator disclosed is secured to a pneumatic tire valve to sense tire pressure and emit an audible signal when the tire pressure goes below a predetermined value. A connector of the indicator is initially threaded onto the tire valve and a cap thereof is subsequently threaded onto the connector. The connector includes a valve opener that opens the tire valve so that pressurized tire air flows to a pressure sensing valve which prevents air flow to the cap when normal tire pressures are sensed. A valve element of the pressure sensing valve moves into and out of engagement with a valve seat and is engaged by the first end of a valve actuator that also has a second end projecting toward the cap. The cap includes a housing with a spring that biases an actuating member into engagement with the second end of the actuator so as to move the valve element out of engagement with the valve seat when low tire air pressure is present.

Abstract: Projections made of a different and less abrasion resistant kind of rubber to that constituting the exterior of the tire are arranged to contact the road during low pressure conditions, whereby the amount of rubber worn off indicates the amount of fatigue accumulated and degree of internal damage done by running the tire at that pressure.

Abstract: A pneumatic tire pressure monitor for a tandem set of tires has a housing for being affixed to the outboard tire wheel. The housing includes a first and second chamber communicating with the interior pressure of each pneumatic tire of the tandem set of tires. The housing further includes a third chamber containing hydraulic fluid for maintaining a reference level of pressure. A diaphragm is responsive to pressure differentials between the first and second chambers and the third chamber to activate a latch. The latch releases a visual signal member, which moves from a retracted position within the housing to an extended position in order to signal a drop in pressure in either or both of the tires. In an alternate embodiment, the monitor may be used to monitor the pressure of a single pneumatic tire.

Abstract: A pressure-responsive signalling valve for use on pneumatic tires is adapted to generate a highly efficient acoustical signal whenever the pressure within the tire falls outside of a predetermined range. The emitted signal is detected by means of an acoustical receiver which, in turn, is coupled to an alarm typically in the form of a warning light or audio device conveniently located within the vehicle to alert the driver. The acoustical valve employs a rolling or flat seal disc diaphragm and a flat sealing arrangement providing a positive sealing action, minimal friction, low hysteresis and extremely precise pressure response characteristics.

Abstract: A device for indicating whether the pressure in a pressurized vessel, such as a pneumatic tire, is at or above a desired predetermined level. The device employs pressure-biased indicating means held by releasable means employing a floating latch member in a position indicating vessel pressure at or above the desired level. The indicator means is released by movement of the release means and floating latch member, upon decrease of the pressure in the vessel below the desired level, to move to another position for indicating loss of pressure in the vessel.

Abstract: A tire pressure indicator includes a cylindrical housing having an axial bore communicating with the interior of a pneumatic tire either through the tire valve stem or directly through the wheel rim. A valve poppet is movable within the housing between a first position in which it seals the tire by engaging a shoulder projecting inwardly in the bore and a second position in which it is spaced from the shoulder to release air from the tire. A hollow cap threadedly connects to the housing and, when so connected, compresses a spring in the housing that biases the poppet toward its second, releasing position against the air pressure in the tire biasing the poppet toward its first, sealing position. When the pressure in the tire drops to a predetermined level, the poppet moves to its second position releasing air into the cap. An indicating element normally concealed within the cap is projected from the cap by the released air to provide a visual warning of the tire pressure drop.

Abstract: Excessively high or low tire pressure is detected automatically with a warning signal generated for the operator. A device is attached to each wheel and includes a spring-loaded piston mounted for reciprocation in a cylinder formed in the device. The cylinder is provided with a porting arrangement which opens only at certain pressure limits. When the ports are opened a sonic or ultrasonic signal is generated and detected by sensors located in proximity to each wheel. The signals detected by the sensors are processed and utilized to actuate a warning signal that provides a visual and/or audio output for the operator. Means are provided for discriminating between background noise and the generated signal as well as to discriminate as to the location of the affected tire. In a modification of the invention, a reserve chamber is integrated into the body of the wheel and is adapted to replenish automatically air lost from the tire.

Abstract: A method of detecting puncture of a pneumatic tire is disclosed. The method comprises guiding an internal pressure applied to the tire through a pressure outlet opening provided in that portion of a rim which is faced to a tube into an alarm means. The alarm means may be a whistle or a buzzer circuit which becomes operated when puncture occurs to produce alarm sound.

Abstract: A device for indicating when the air within a tire is above or below an optimum pressure range, comprising a housing having a bore therein in which a piston is movable. The piston is spring biased toward one end of the bore and is normally held in a medial sealing position by air pressure from within the tire. In such sealing position, a sealing ring on the piston engages a sealing section of the bore to prevent movement of air along the bore; when the air pressure exceeds or falls below the optimum range, the sealing ring moves over a relieved portion of the bore and allows air to move along the latter to actuate a whistle carried by the piston. An electronic device senses the whistle and signals the operator.

Abstract: A wheel-mounted tire pressure indicator which includes a housing enclosing a pneumatically-actuated pressure indicia scale as well as a self-contained battery and circuit for energizing a signal light on the housing when the tire pressure is below a predetermined selected value.

Abstract: An indicator device positioned in the passenger compartment of an automotive vehicle to warn the operator of the vehicle when the air pressure in a spare tire, disposed in a remote location, is too low for emergency usage.

Abstract: A low pressure tire valve assembly having a standard tire valve core unit encapsulated at its lower end into a flexible rubber plug which has molded to it a distensible cylindrical member which biases a plurality of circumferentially spaced springs into latching engagement with an indicator cap. The indicator cap is ejected by spring means upon a loss of pressure due to collapse of the distensible member. Cord means interconnects the cap to the tire valve assembly.

Abstract: A gas-actuated sound signal generator is provided to produce a simple, reliable sound signal of predetermined frequency, or combination of frequencies. The signal generator is intended for use primarily with a tire pressure sensing system on a vehicle as a means for transmitting the occurrence of a low tire pressure condition from a wheel to a microphone mounted in fixed position to the vehicle and connected via processing circuitry to an alarm near the operator. The device is operated upon the release of a small amount of air from the tire if the tire pressure drops, for example, below a preset limit. The air released from the tire flows into the signal generator and is converted into a sound signal for detection by the microphone. The signal generator is comprised of a cavity block, a shim and a cover. The block contains an entrance feed through which air is admitted as from the tire and a cavity spaced from the entrance feed.

Abstract: An air leakage warning device for a pneumatic tire is described which comprises a housing member including in longitudinal direction a cylindrical intermediate section, an enlarged cylindrical lower section connected to the cylindrical intermediate section through a shoulder portion, and a four-sided upper section having a circular at the outmost end; a cylinder or tubular member containing a perforated piston means and a coil spring responsive to a predetermined pressure within the tire, the upper end of the cylinder member being inter-connected with the lower section of the housing member while the lower end thereof is secured to a base member which is adapted to be secured to the air filling valve stem of the pneumatic tire; a rubber ball being freely movable in the space defined by the housing member and the upper end of the cylinder member; and a rubber sack forming a receiver for escaping tire air and adapted to be ruptured by its contained air pressure so as to give an audible signal, the rubber sack h

Abstract: A pneumatic tire pressure indicator adapted to be attached to a valve stem of a pneumatic tire for designating a low pressure condition therein includes a member defining at least one window in a housing, and an attention-attracting member mounted on the housing out of proper orientation relative to the window to conceal the attention-attracting member from view when normal air pressure exists within the tire. A mechanism rotates the members relative to one another to properly orient them to expose the attention-attracting member through the window for indicating purposes when the tire pressure falls below a predetermined value. A sensing mechanism activates the rotating mechanism when the pressure within the pneumatic tire falls below the predetermined value.

Abstract: An air switch senses abnormally low pressure in a tire and provides a pneumatic signal to an actuator which moves a magnet from a normal position to a warning position. An electrical detection system senses that the magnet is in a warning position and provides a low pressure warning signal to the vehicle operator. The actuator contains a mechanical latch to assure that the magnet remains in a warning position even if the pneumatic signal should cease. A reset feature allows the latch to be disengaged to return the actuating mechanism to normal condition when proper tire inflation pressure has been restored.

Abstract: Apparatus for warning a driver of low tire inflation, especially on multiwheel vehicles, including a collapsible warning bladder positioned in a dust cover can having a snap-open cover on a wheel hub of the vehicle, pressure line conduit from the dust cover to a plurality of different tire valve stems, and valve means between the conduit and valve stems operable to connect the bladder with tire air pressure in response to a predetermined tire air pressure which is lower than a desired pressure, which valve means includes a check valve for preventing deflation of the bladder after inflation thereof.

Abstract: An electrical brush contact for use in an electrical circuit requiring the conduction of electrical energy between relatively moving objects, said contact having a contactor block mounted on one of said objects and a block engaging brush mounted on the other object, said brush providing a stud disposed adjacent to the path of relative movement of the block, a helical spring mounted on the stud having an anchored end and an opposite end, and a plurality of wire bristles mounted on said opposite end of the spring and substantially tangentially extended therefrom for block engagement.

Abstract: A combined gauge and inflator for a tire includes a support member threaded on the tire stem with a body slidably disposed within the support member and locked in a first position. The body has a passage extending therethrough with a spring-biased piston slidably disposed therein. With the body in the first position, the piston rests against a spring-biased plunger, which opens the valve in the tire stem when the plunger spring is overcome. The plunger spring is overcome either by an air chuck acting on the piston to move the piston against the plunger or when the body is moved from its first position to a second position in which the body engages the plunger. When the body is moved against the plunger, sealing means on the piston seal the body passage so that air pressure in the tire moves the piston relative to the body. A scale on the piston cooperates with a marker on the body to indicate the pressure of the tire.