Abstract: A reverb generator comprises a delay circuit for delaying an input audio signal, a feed back path connecting an output port of the delay circuit to its input port, and a phase shifter connected in series to the delay circuit. The phase shifter produces a dispersion in the spectrum of the input audio signal in accordance with frequency dependent delay characteristic in such a manner that the delay time is large in a low frequency range and small in a higher frequency range. By including the phase shifter in the feed back path, one can obtain an output audio signal having a spectrum which is repeatedly subjected to dispersion, thus simulating the effect of dispersion due to the multiple reflections taking place in an actual concert hall.

Abstract: A multi-channel reproducing system comprises main speakers for sounding an input audio signal as a main channel audio signal, a phase shifter supplied with the input audio signal for shifting a phase thereof, and sub-speakers supplied with an output signal from the phase shifter as a sub-channel audio signal for sounding the sub-channel audio signal. The phase shifter has a frequency versus delay time characteristic in which a delay becomes large as the frequency decreases and small as the frequency increases.

Abstract: An audio signal amplifier for an electromagnetic transducer, comprises a transformer which has a primary winding coupled to the electromagnetic transducer for receiving an output audio signal from the electromagnetic transducer and a secondary winding for producing a transformed audio signal as an output. The transformer has a turn ratio of the primary winding and the secondary winding which is selected to n:1, where n is a real number greater than 1. The audio signal amplifier further comprises a current-voltage conversion circuit which is coupled to the secondary winding of the transformer for converting an audio signal current from the secondary winding into an audio signal voltage.

Abstract: An electronic control fuel injection system for a spark ignition internal combustion engine is described which controls air flow rate as function of fuel flow rate by transmitting an operator's depression stroke of an accelerator pedal to a fuel selecting mechanism which determines the fuel flow rate, applying a signal representative of the selected fuel flow rate to a computer together with various correction information, calculating by the computer from the selected fuel flow rate and correction information, the optimum air flow rate, and determining the opening of a throttle valve from the calculated result via a throttle valve servo mechanism. The invention is particularly useful in eliminating hesitation of an automobile while attaining both fuel economy and low harmful exhaust emissions.

Abstract: A circuit device for driving an electromagnetically movable unit at a high speed with a single power source such as a battery comprises a plurality of power transistors for inverting the polarities of the input power, a pair of control transistors connected via a NOT element to the control circuit of the transistors for turning then alternately on or off, and instantaneous double voltage generator connected to the output circuit of the power transistors. Rapid responsiveness of the circuit device can be obtained by magnetically driving the movable unit in both one way and return way without a conventional return spring.

Abstract: An exhaust gas recirculation valve driven by an electric motor. The valve comprises a housing having an inlet port and an outlet port, a valve member disposed within said housing, an electric motor attached to the upper portion of said housing, a changing means for changing the rotation of said electric motor into the vertical movement of said valve member, said changing means being disposed between the shaft of said electric motor and a valve rod. The valve member is operated by said electric motor through the intermediary of said changing means. Therefore, the valve can be controlled delicately independent of the engine manifold vacuum. The valve may be incorporated into an electronic fuel injection system adapted to calculate the amount of fuel supply to an internal combustion engine by means of a control unit so as to obtain an optimum air-fuel mixture or air-fuel ratio.

Abstract: A throttle valve disposed within the intake bore of an internal combustion engine. The valve thickness is large, preferably more than about 1.5 mm and less than 1/10 of the valve diameter. The full closed angle of the valve is less than 5.degree.. The circumferential edge of the valve has a roundness having a radius less than about five times as large as the valve thickness. When the valve is fully closed, there is a clearance L of about 1/10,000 to 5/1,000 of the intake bore diameter between the circumferential edge of the valve and the inner surface of the intake bore. The valve reduces the degree of air flow change at small opening angles of the valve as in the idling or low-speed operation of the engine so as to reduce the change of air flow caused by the change of the valve opening. Thus, an optimum air-fuel ratio in a range of small opening angles of the valve can be easily maintained.

Abstract: A throttle valve actuating system in an electronic control fuel injection system for a spark ignition internal combustion engine which controls air flow rate as a function of fuel flow rate, wherein a throttle valve is made to be able to be opened and closed by a throttle actuator and pneumatic actuator in order to reduce the electric power consumption and to avoid the actuation delay with the variations of the operating conditions and environmental conditions. The throttle valve is operated by such a separate actuating power source as a step motor or the like without directly connecting the throttle valve to an accelerator pedal.

Abstract: A throttle valve driving mechanism comprising an actuator disposed near a throttle valve shaft, and an oscillating slide block mechanism disposed between an actuator shaft and said throttle valve shaft. Said oscillating slide block mechanism comprises a throttle lever provided at one end thereof with a roller, an actuator shaft disposed in a position on a straight line between said throttle valve shaft and said roller at the time when the throttle valve is fully closed and a certain distance away from the center of said roller toward the center of said throttle valve shaft, a rotatable lever secured to said actuator shaft, said rotatable lever having a groove within which said roller slides freely with small clearances, the center of said throttle valve shaft, the center of said roller and the center of said groove being arranged in the same direction when the throttle valve is fully closed.

Abstract: A fuel feed system of a fuel priority type for an internal combustion engine. The fuel feed system of the invention has a small auxiliary control unit with no calculation function in addition to a main control unit. When the main control unit malfunctions or is out of order, it is changed over to the auxiliary control unit which insures injection, for instance, at a constant air fuel ratio and in proportion to the degree of movement of an accelerator pedal. Therefore, even when the main control unit is out of order, the driver can drive his vehicle safely to a service station, etc., without stopping the engine. When the main control unit is in a normal state, the main control unit performs engine air control (EAC) at a variable air fuel ratio in the entire range of operation.

Abstract: A circuit for driving a solenoid at a high speed with a choke coil, which has a pair of switching circuits alternatively turned ON and OFF by a transistor, a solenoid coil connected to one of the switching circuits, a resistor connected to the other of the switching circuits, and a choke coil connected in series with the switching circuit and in parallel with a power source. Thus, this circuit can abruptly raise an electric current flowing through the solenoid coil by utilizing the constant current characteristics of the choke coil and the current switching characteristics of the transistor.

Abstract: An electronic control fuel injection system for a spark ignition internal combustion engine is disclosed which controls air flow rate as a function of fuel flow rate by converting an operator's depression of an accelerator pedal to an electric signal, applying the signal to a computer which preferentially determines the fuel flow rate and then the air flow rate, and feedback controlling the air flow rate by using the determined air flow rate and an actual air flow rate sensed by a pressure sensor provided at the upstream and downstream sides of a throttle valve and/or a throttle opening sensor. The computer also receives signals representative of the fuel line pressure and the air pressure in a region adjacent one or more injectors and uses this in adjusting the supply of fuel to the injector(s) to obtain a predetermined constant pressure difference thereacross. A unique digital flow control valve may also be used to precisely adjust the air flow rate.

Abstract: A record player comprises a tone arm provided at the distal end thereof with a pickup cartridge, and a vibration damping device for damping a resonance of the tone arm. The damping device comprises a damping member made of an electrically conductive material and provided at the tone arm in a manner to vibrate unitarily therewith, and a damping unit inclusive of permanent magnet means for forming a magnetic field with respect to the damping member. Eddy currents are generated in the damping member when the damping member vibrates in the magnetic field, whereby damping of the vibration of the damping member and the tone arm is accomplished. The damping device may further comprise an elastic member supported at one end thereof at the tone arm and having another free end and a weight secured to the free end of the elastic member.