Abstract: A pressure regulator valve includes: a housing including a base, a cover, and a body; a valve element configured to open and close a valve passage by moving between a closed position and an open position, the valve element being further configured to reduce a primary pressure to a secondary pressure and receive the secondary pressure by which the valve element moves toward the closed position; a biasing unit accommodated in an accommodating space formed between the body and the cover, the biasing unit being configured to bias the valve element such that the valve element moves toward the open position; a first sealing member provided at a gap between the base and the body; and a second sealing member provided a gap between the base and the cover and made of synthetic rubber. The second sealing member is arranged away from the body.

Abstract: A pressure regulator valve includes: a housing including a base, a cover, and a body; a valve element configured to open and close a valve passage by moving between a closed position and an open position, the valve element being further configured to reduce a primary pressure to a secondary pressure and receive the secondary pressure by which the valve element moves toward the closed position; a biasing unit accommodated in an accommodating space formed between the body and the cover, the biasing unit being configured to bias the valve element such that the valve element moves toward the open position; a first sealing member provided at a gap between the base and the body; and a second sealing member provided a gap between the base and the cover and made of synthetic rubber. The second sealing member is arranged away from the body.

Abstract: A voltage switching amplifier circuit has a comparator which, after comparing signal amplitude to a comparison voltage, switches on a high voltage or low voltage amplifier depending upon whether the comparison voltage is exceeded or not. After the predetermined comparison voltage is exceeded, a positive feedback circuit reduces the comparison voltage enabling the high voltage amplifier to continue operation at least until the signal amplitude drops below the reduced comparison voltage. In a preferred embodiment, a time constant circuit maintains the high voltage amplifier in operation for a predetermined period of time during which the signal amplitude has dropped below and remained below the reduced comparison voltage.

Abstract: A bias circuit for single-ended push-pull amplifiers permits class A or class AB operation while substantially reducing the idling current of the output transistors at low input signal levels. The bias circuit includes a DC current limiting circuit comprised of transistors that are connected between the common output of the amplifier and the bases of the output transistors. The transistors of the DC current limiting circuit limit the idling currents of the output transistors when there is no input signal applied to the amplifier. The bias circuit further includes RC/diode circuits which operate to increase or decrease the bias voltages of the transistors of the DC current limiting circuit corresponding to a decrease or an increase of the output voltage of the amplifier. In this way, the idling currents of the output transistors are changed so as to effectively follow the input signal power.

Abstract: A low pass filter is connected to a junction of a direct-coupled amplifier. The amplifier has a single-ended push-pull output stage consisting of two output transistors and series-connected two resistors. The output transistors are connected to a positive and negative d-c power sources, respectively. The series-connected two resistors are interposed between the two output transistors and defines an intermediate point therebetween at which substantially zero d-c voltage prevails when the amplifier is functioning normally. The junction of the amplifier, to which the low pass filter is connected, is between one of the output transistors and the series-connected resistors. The low pass filter is supplied with the voltage at the junction and applies its output to following isolating means. The means responds to the output of the low pass filter for isolating the intermediate point from a load device connected thereto.

Abstract: In a differential amplifier having a current mirror circuit, the improvement where the collectors of a pair of transistors comprising the current mirror circuit are respectively connected to the bases of a pair of transistors of polarity reverse that of the current mirror transistors, the collectors of the reversed polarity transistors are connected to a power supply, the emitters of the reversed polarity transistors are connected to corresponding active elements of the differential amplifier, and resistors are respectively connected between the bases and emitters of the reversed polarity transistors.

Abstract: An amplifier circuit having an input adapted to receive a signal to be amplified from a signal source, at least two sets of combined amplifying transistors and associated power sources for the amplifying transistors, the two sets constituting first and second amplifying stages, a switching transistor for automatically switching the amplifying operation of the amplifier circuit from the first amplifying stage to the second amplifying stage depending upon the amplitude of the input signal to the amplifier and a load to which the amplifying transistors are connected in parallel.

Abstract: In a preamplifier having integrated circuitry, the improvement where the active elements of the first stage amplification of the preamplifier and the resistor which establishes the current flowing through these active elements are mounted on the outside of the integrated circuitry and the connecting terminals for the active elements and resistor are disposed with the remaining preamplifier components inside the integrated circuitry.