Abstract: An easily restarted brushless DC motor has a skeleton type stator core, a rotor core having permanent magnets arranged around it, and needs only one position sensor adapted to detect a rotational position of a rotor and only one stator coil. A controller is provided for switching over the polarity of the electrical power supplied to the stator coil in accordance with an output of the position sensor.

Abstract: At least two microcomputers are provided for the controlling operation of an automatic vending machine, which are connected by signal wires of a number selected from one to four with respect to each other. One of the microcomputers is a main microcomputer, while the other thereof is a submicrocomputer. The submicrocomputer performs the controlling operation on the restricted block functions of the automatic vending machine, while the main microcomputer transmits control codes to the submicrocomputer through the signal wire to control the operation thereof, and controls the automatic vending operation while serially transmitting or receiving the necessary data.

Abstract: A variable reactance circuit which can produce equivalent reactance varying from negative given values to positive given values in accordance with fundamental reactance elements such as capacitor, coil, etc. The present invention has a big advantage of being capable of easily producing the positive, negative equivalent reactance given times as much as the basic reactance element with the use of a circuit which can be integrated.

Abstract: A hermetically sealed motor compressor for use in a small-size refrigerating machine, refrigerator, freezer and the like has a compressor on which is mounted a silencer comprising in combination a suction muffler of thermal insulating and a discharge muffler made of formed metal plates. The suction muffler has an suction port disposed near the open end of a suction coupling fixed to a sealed casing, and also has an connection pipe connected to a compressor cylinder and having a distal end fitted directly in a hole defined in an head plate which is mounted on the head of the cylinder. A refrigerant gas as it is introduced from the suction coupling into the sealed casing can be drawn into the cylinder through the suction port, the suction muffler and the connection pipe to minimize heat transfer to the suction gas, so that the compressor can increase its volumetric efficiency.

Abstract: An induction heating coil and a self-excited inverter are connected to a ripple voltage source. The self-excited inverter comprises a transistor as a switching element and the transistor is rendered conductive responsive to a drive voltage applied for each cycle of the ripple voltage source, whereby the self-excited inverter is started at each cycle of the ripple voltage source. The self-excited inverter stops the oscillation when the voltage of the ripple voltage source becomes lower than a predetermined value. During the non-oscillation period of the intermittent oscillation, the oscillation output of the self-excited inverter is detected. If and when the oscillation output is detected at that time, the oscillation of the inverter is stopped. Furthermore, the pulses of the attenuating oscillation of the self-excited inverter during the oscillation rest period are counted.

Abstract: An induction heating coil and a self-excited inverter are connected to a ripple voltage source. The self-excited inverter comprises a transistor as a switching element and the transistor is rendered conductive responsive to a drive voltage applied for each cycle of the ripple voltage source, whereby the self-excited inverter is started at each cycle of the ripple voltage source. The self-excited inverter stops the oscillation when the voltage of the ripple voltage source becomes lower than a predetermined value. During the non-oscillation period of the intermittent oscillation, the oscillation output of the self-excited inverter is detected. If and when the oscillation output is detected at that time, the oscillation of the inverter is stopped. Furthermore, the pulses of the attenuating oscillation of the self-excited inverter during the oscillation rest period are counted.

Abstract: An off-line switching regulated power supply employing a switching transistor, wherein the base drive system is improved to supply a reverse base current, remaining an interval after the termination of a forward base current, thereby the influence of the storage time of the switching transistor is removed and various drawbacks including the problem due to the incompatible characteristics of a breakdown voltage and switching speed, the problem due to delay in turning-off and the problem of overheating, are removed, resultantly enabling to provide a switching power supply which is allowed to employ a higher switching frequency.

Abstract: An absorption heat pump system having a generator, a condenser, an evaporator and an absorber connected hermetically to form closed cycles for a refrigerant and an absorbent, comprising a control means disposed in the refrigerant passage leading from said condenser to said evaporator and adapted to continuously controlling the temperature or flow rate of the liquid refrigerant, thereby to stabilize the temperature in said evaporator.

Abstract: A noise detecting circuit in a television receiver, which comprises a horizontal synchronizing signal separating circuit (17) for separating a horizontal synchronizing signal from a detected composite video signal, a differential circuit (101) for extracting a noise component included in the horizontal synchronizing signal period of the composite video signal as a function of the separated horizontal synchronizing signal, and a rectifying circuit (102) for rectifying the extracted noise component for providing a direct current voltage associated with the magnitude of the noise component in the composite video signal. The noise detected output is applied to an automatic frequency control circuit (26) for the purpose of controlling the sensitivity of an automatic frequency control operation thereof. The noise detected output is also applied to the automatic frequency control circuit (26) for the purpose of controlling the impedance of a filter thereof.

Abstract: A control device for brushless motor comprises an inverter (3), a control circuit (8) and a rotor position detecting circuit (9). In the rotor position detecting circuit (9), voltage induced in stator coils (U, V and W) due to rotation of a rotor (7) and neutral voltage at a virtual neutral point (25) are compared by comparators (CU, CV and CW) so that polarity changing points can be detected. The control circuit (8) controls the inverter (3) based on the above stated polarity changing points so as to control changeover of the modes for conducting to the stator coils (U, V and W). As a result, rotation of a brushless motor can be controlled without using Hall elements.

Abstract: A tuning control apparatus of a receiver having an electronic tuner comprises a tuning voltage generating circuit including a window comparator, a charge pump and a low-pass filter. An S curve signal is applied to the window comparator to make a search controlled by means of a voltage synthesizer system using the S curve signal until the receipt of a broadcasting signal. If an optimum tuning point is established through the search control, the local oscillation frequency at that time is counted to provide frequency division ratio data. A phase-locked loop is operated as a function of the frequency division ratio data on the occasion of the above described optimum tuning point, whereby reception of the broadcasting signal is continued. Preferably, an automatic frequency control operation is performed before the phase-locked loop is operated.

Abstract: An absorption refrigeration system having a generator, a rectifier, a condenser, an evaporator, an absorber and heat exchangers which are connected by means of conduits in an airtight manner so that circulations for refrigerant and for absorbent solution are formed, wherein the rectifier is mounted upright above the generator, and wherein a receiver for receiving absorbent containing refrigerant is mounted below the rectifier and communicates with the lower portion of the generator through an absorbent passage means, whereby decreasing hindrance of the generation of the refrigerant vapor from the generator, thus increasing the efficiency in generating vapor and, at the same time, preventing local overheating of the solution in the generator.

Abstract: A ladder-type signal attenuator comprises a ladder network (50) storing a ladder resistor circuit of a plurality of stages (n-1) each having an input resistor (2R) and an output resistor (R) and a ladder portion of the final stage (n) having an input resistor (8) and an output resistor (7) and coupled to the ladder resistor circuit. The resistance value (RB) of the input resistor (8) of the ladder portion of the final stage is different from 2R and/or the resistance value (RA) of the output resistor (7) is different from R. A bias voltage (Vb) or an analog input signal (Sin) is selectively applied to a corresponding signal input terminal of the ladder circuit (50) by means of switches (S.sub.1 to S.sub.n) in response to control data (b.sub.1 to b.sub.n) of n bits. At least one of the resistance values of the two resistors (7, 8) of the final stage ladder portion is changed as a function of the state "0" or "1" of the final bit (b.sub.

Abstract: A Schmitt circuit comprises a series connection of a first, second and third MOS transistors connected between a voltage source and the ground, and a fourth MOS transistor connected between the voltage source and the junction of the second and third MOS transistors. An input voltage is applied to the gates of the second and third MOS transistors. The voltage at the junction of the first and second MOS transistors is applied to the gate of the fourth MOS transistor and is also led out as an output. The Schmitt circuit further comprises a series connection of a sixth and seventh MOS transistors connected between the voltage source and the ground for dividing the source voltage, and a fifth MOS transistor connected between the junction of the sixth and seventh MOS transistors and the junction of the first and second MOS transistors and adapted to be rendered conductive when the potential at the said junction exceeds a predetermined voltage.

Abstract: Oil burner, having an ignition mechanism and a wick movable upwardly and downwardly, and being operated with ease by completing wick lifting and ignition simultaneously in a single operation.

Abstract: An induction heating coil and a self-excited inverter are connected to a ripple voltage source. The self-excited inverter comprises a transistor as a switching element and the transistor is rendered conductive responsive to a drive voltage applied for each cycle of the ripple voltage source, whereby the self-excited inverter is started at each cycle of the ripple voltage source. The self-excited inverter stops the oscillation when the voltage of the ripple voltage source becomes lower than a predetermined value. During the non-oscillation period of the intermittent oscillation, the oscillation output of the self-excited inverter is detected. If and when the oscillation output is detected at that time, the oscillation of the inverter is stopped. Furthermore, the pulses of the attenuating oscillation of the self-excited inverter during the oscillation rest period are counted.

Abstract: A speed control apparatus for a direct current motor comprises a bridge circuit having an armature in one side thereof, a direct current voltage source, and a series connection of a switching transistor and an inductor inserted between the direct current voltage source and the bridge circuit. A detecting transistor detects an unbalanced voltage of the bridge circuit and control transistors are responsive to the detection to control the switching transistor to be turned on or off. The inductor stores a magnetic energy when the switching transistor is turned on and supplies an electromotive force induced by the stored magnetic energy to the bridge circuit when the switching transistor is turned off. To that end, a diode or a transistor cooperates with the inductor and the bridge circuit to constitute a closed loop. A capacitor is connected in parallel with the armature, thereby to restrict the operation of the detecting transistor and thus the on/off-period of the switching transistor.

Abstract: A plug-in electronic clock being operated either by a commercial power source in a normal state or by a D.C. power source in case of a power failure, said electronic clock having means for generation of a pulse train used for a computation of time information in case of a power failure and means for stopping generation of the said pulse train in a case where the commercial power is active so as to prevent interference noise against radio receivers or television receivers, with a correct time information computation being assured when the commercial power source is recovered.

Abstract: A pulsive noise removing apparatus comprises a subtracting circuit (35) receiving one input thereto a stereo composite signal directly from a delay circuit (31). A stereo switching signal is generated as a function of a stereo pilot signal included in the stereo composite signal and a cancel signal of the same level, the same frequency and the same phase as those of the stereo pilot signal is generated as a function of the stereo switching signal. A gate (67) is interposed between the output of the cancel signal generating circuit (65) and the other input of the subtracting circuit and the gate is interrupted responsive to detection of a pulsive noise included in the composite signal. The pulsive noise is removed due to interruption of the gate and the stereo pilot signal is prevented from appearing at the output of the subtracting circuit irrespective of conduction or interruption of the gate.

Abstract: A demodulating circuit is capable of controlling stereo separation as a function of an electric field strength. An intermediate frequency signal not limited obtained from an intermediate frequency circuit is utilized as a signal representative of the level associated with the electric field strength. Stereo separation is discontinuously controlled as a function of the signal representative of the electric field strength. The separation is maintained in the possible maximum value in the region exceeding a predetermined value of the electric field strength but is abruptly decreased to a given value between a stereo state and a monaural state from the above described maximum value (stereo state) when the electric field strength becomes smaller than the above described predetermined value and the separation is changed as a function of the electric field strength in the region smaller than the above described value of the electric field strength.