Abstract: A device for automatically measuring the compressibility of a tennis ball or the like. The tennis ball tester of the present invention contains three main components: a case to compress the ball to a fixed dimension; a force sensor to measure the force applied to the ball; and an electronic comparative circuit to determine the force level against a standard and to activate a LED indicator for displaying a "go-no go" output. In operation, the ball is first placed in the case and compressed to a fixed dimension by closing the lid of the case. This dimension is the maximum the ball should be compressed by an 18 lb. specified force. As the ball is compressed, the tennis ball tester measures the applied force to determine if the force is less than or greater than the 18 lb. specified force. The force sensor measures this force and supplies an electrical signal proportional to the force measured.

Abstract: In wrapping machinery for wrapping articles in heat sealable plastic film, a web of film is drawn from a supply roll and is severed by pulling the film under tension downwardly onto the narrow edge of a thermal cut-off device, which may be a heated rod or blade, to melt the film material along a thin transverse line and to permit severance thereof by pulling. Following severance of the film, the film-wrapped package is sealed by placing the package on a pedestal hot plate. The temperature of the hot plate is higher than that of the thermal cut-off device used to sever the film. The hot plate is supplied by electrical energy from a single source through a temperature sensor and control. The thermal cut-off device obtains its heat by conduction from the hot plate.

Abstract: An air core meter movement having return-to-zero means. Permanent magnets mounted within the deflection coils provide a field which interacts with the rotor magnet to return the pointer to zero when no power is applied to the meter. A compensating coil is also included to counteract the effects of the permanent magnets when measurable signals are applied to the deflection coils.

Abstract: A magnetostrictive pressure transducer is disclosed wherein pressure in the range of zero to 1000 psi can be accurately measured. The pressure transducer apparatus includes a diaphragm causing the pressure to be applied unidirectionally on sensor material having the property of undergoing changes in magnetic induction when a pressure is applied thereto, the change in magnetic induction being related to the applied pressure. The change in magnetic induction is measured and thus provides a measurement of the applied pressure. Several embodiments are also disclosed for measuring vacuum. In these embodiments force is also applied unidirectionally on the sensor material.

Abstract: A magnetostrictive pressure transducer is disclosed wherein pressure in the range of zero to 1000 psi can be accurately measured. The pressure transducer apparatus includes a diaphragm causing the pressure to be applied unidirectionally on sensor material having the property of undergoing changes in magnetic induction when a pressure is applied thereto, the change in magnetic induction being related to the applied pressure. The change in magnetic induction is measured and thus provides a measurement of the applied pressure. Several embodiments are also disclosed for measuring vacuum. In these embodiments force is also applied unidirectionally on the sensor material.

Abstract: A magnetostrictive pressure transducer is disclosed wherein pressure in the range of zero to 1000 psi can be accurately measured. The pressure transducer apparatus includes a diaphragm causing the pressure to be applied unidirectionally on sensor material having the property of undergoing changes in magnetic induction when a pressure is applied thereto, the change in magnetic induction being related to the applied pressure. The change in magnetic induction is measured and thus provides a measurement of the applied pressure.

Abstract: A speed sensing mechanism for a motor vehicle skid control system has ferromagnetic portions spaced around the periphery of an exciter wheel, the exciter wheel being adapted to be mounted for movement with a motor vehicle wheel whose speed is to be monitored to move the ferromagnetic portions of the exciter wheel in a plane through a station at a rate or frequency corresponding to the speed of vehicle wheel rotation. A permanent magnet is disposed within a wire sensor coil and is mounted at the station with a first pole face in closely spaced relation to the plane of movement of the ferromagnetic portions of the exciter wheel so that the reluctance of the magnetic circuit established by the permanent magnet is varied as each of the ferromagnetic elements is moved through the station, thereby to induce an electrical signal in the coil having a frequency corresponding to vehicle wheel speed.

Abstract: A magnetostrictive pressure transducer is disclosed wherein pressure in the range of 0 to 1000 psi can be accurately measured. The pressure transducer apparatus includes a diaphragm causing the pressure to be applied unidirectionally on sensor material having the property of undergoing changes in magnetic induction when a pressure is applied thereto, the change in magnetic induction being related to the applied pressure. The change in magnetic induction is measured and thus provides a measurement of the applied pressure. Several embodiments are also disclosed for measuring vacuum. In these embodiments force is also applied unidirectionally on the sensor material.

Abstract: An air core meter movement having return-to-zero means. Permanent magnets mounted within the deflection coils provide a field which interacts with the rotor magnet to return the pointer to zero when no power is applied to the meter. A compensating coil is also included to counteract the effects of the permanent magnets when measurable signals are applied to the deflection coils.