Abstract: A liquid level indicator system is provided for sensing the presence of liquid at a preselected level in a liquid containing container. A piezoelectric reed transducer is disposed in the container for detecting vibrational movement and for producing an electrical signal in response to the vibrational movement. Operationally coupled to the transducer is a paddle which is sized to be immersed in the liquid when the liquid is present at the proper level. Immersion of the paddle in the liquid inhibits the transducer from vibrating due to fluid resistance against the paddle and accordingly inhibits an electrical signal output from the transducer. A control circuit is provided for sensing the electrical signal generation and for generating an alarm signal representative of low liquid level. A tubular housing is provided for containing a level of liquid representative of liquid level in the liquid container. The reed is preferably tuned to a preselected natural frequency sympathetic to ambient system vibrations.

Abstract: A system and method for adjusting the frequency of operation of a radio frequency circuit including an inductive loop having an adjustable exposed inductor portion is provided. The frequency of operation of the circuit is first detected with means for detecting a parameter relating to and representing the frequency of operation. The adjustable inductor portion is associated with a selectively movable actuator device coupled to the frequency detecting means and a source of signals representing a predetermined frequency of operation for the circuit. A control circuit means, preferably a computer, is coupled to the detecting means and to the source of signals to provide an output control signal when the detected frequency of operation bears a predetermined relationship to the predetermined frequency of operation.

Abstract: A device is provided for sensing the condition of a pneumatic tire preferably of the type used on an automobile wherein the tire is mounted on a tire rim and the tire is subject to normal vibrations. The device comprises a housing, a band for mounting the housing to the tire rim, a sensor for monitoring the condition within the tire, circuitry operatively connected to the sensor for generating radio signals indicative of the tire condition, power supply operatively connected to the circuitry and a receiver for receiving the radio signals. The power supply includes a piezoelectric reed having a base portion and an end portion. The base portion is elastomerically bonded to the housing. A tuning mass member is mounted to the end portion and is configured for mating abutment against stop members which limit the flexure stroke of the piezoelectric reed and inhibit compound bending of the reed.

Abstract: An abnormal tire condition warning system is disclosed for use in pneumatic tires. The self-contained device comprises a sensor, an electronic transmitter and a power supply. The power supply is a weighted, vibrating arm that has a piezoelectric transducer attached. Normal wheel vibrations cause the weighted arm to vibrate and flex, in turn causing the transducer to flex, thus producing electrical energy.

Abstract: A self-leveling viscous elastic damper comprising an inner member at least partially received in an outer member and joined to the outer member with an elastomeric shear spring. A main fluid chamber is included in the outer member in communication with a second fluid chamber in the inner member through restricted orifice means. A third fluid chamber, separated from the main fluid chamber by a partitioning wall, is also included in the outer member. An elastomeric bladder for selective gas pressurization is disposed in the second fluid chamber. An elastomeric gas accumulator for selective gas pressurization is disposed in the third fluid chamber. Pump means extend through the partitioning wall for pumping fluid from the third fluid chamber to the main fluid chamber. An elastomeric diaphragm in the main fluid chamber connects the pump means to a peripheral wall of the outer member.

Abstract: A ball joint construction having a ball-stud member with a ball portion and a shank portion and an open-ended socket member into which the ball portion is inserted. An elastomeric covering is permanently bonded to both the ball member and a part of the shank portion to provide increased bond life and strength and then deformed for inserting in the open end of the socket thereby resiliently interconnecting the socket and ball members. An additional rib or lip of elastomer is provided on the covering of the ball adjacent the shank which collapses into a continuous multiple curved pattern during insertion into the socket. The rib provides for increased life of the elastomer by improved surface tension parameters and also keeps stones and other debris out of the open-ended portion of the socket. A further bonding between the socket and elastomer after insertion provides a completely bonded system capable of accepting very substantial angular movement without slippage or pullout.

Abstract: Apparatus and method adapted for detecting the profile deflection condition in a wheel structure of the type comprised of a pneumatic tire mounted on a wheel rim and which deflection may be caused by tire under inflation or overloading. A sensing and actuating structure constructed from flexible material having high flex fatigue characteristics to include a body portion and a profile sensor is conveniently mounted to the drop center portion of the rim such that the profile sensor extends into the tire cavity so that it is positively engaged by the inside of the tire wall when tire profile deflection reaches an amount greater than a predetermined maximum amount due to overloading or under inflation, to thereby cause flexure in the profile sensor generally inwardly toward the rim. This flexure causes a piezoelectric device positioned adjacent the profile sensor to provide an electrical discharge.

Abstract: Apparatus and method particularly adapted for detecting over and/or under inflated conditions in a wheel structure of the type comprised of a pneumatic tire mounted on a wheel rim. A generator unit is mounted to the wheel generally coaxial of the axis of wheel rotation and is constructed such that the generator rotor is operably journalled within the generator stator in a manner facilitating rotation of the rotor independently of the remainder of the generator unit and wheel itself. One side of the rotor is weighted so that as the wheel and generator unit are rotated, the rotor disposition remains generally stationary due to the influence of gravity forces on the weighted area. The relative rotation thus achieved between stator and rotor causes a voltage to be induced in the stator field winding which is utilized to energize a small radio transmitter mounted on the wheel with the generator unit.