摘要:
A low frequency AC voltage is rectified through a full-wave rectifier to obtain a pulsating voltage, which is superimposed with an auxiliary voltage of a predetermined level provided from an auxiliary power source, and the resultant composite pulsating voltage is inverted at an inverter to a high frequency voltage. The high frequency voltage thus obtained from the inverter is used to operate a discharge lamp. Minimum value V.sub.min of the resultant voltage is set to be 1/3 to 4/5 of the maximum value V.sub.max of the resultant voltage.
摘要:
A large number of luminous display elements are arrayed on a board, and the quantity of light emitted by each display element is controlled in accordance with a video signal generated by a video signal generator. Each display element is constituted by a discharge lamp and a high frequency generator lighting the same.
摘要:
An apparatus for operating a gaseous discharge lamp comprises a D.C. power source, a transistor inverter which is connected to the D.C. power source through a switch, provided with at least one inverter transistor and generates an output having a prescribed frequency, and a discharge lamp which is energized by an output from the transistor inverter and having a pair of electrodes heated by part of the output. The apparatus further comprises base current control means which holds the base current of the inverter transistor at a level lower than a first level during a prescribed length of time after the close of the switch, and holds the base current at the first level after the prescribed length of time. The discharge lamp has its electrodes preheated, but does not display discharge when the base current has a level lower than the first level, and commences discharge when the base current reaches the first level and thereafter continues discharge.
摘要:
A large image display apparatus comprises a plurality of discharge lamps each having an anode, a cathode and a light emitting tube, a display board having the plurality of discharge lamps thereon, a heating circuit for heating the cathodes of the plurality of discharge lamps, a power supply circuit for generating a rectified high frequency voltage and biasing the plurality of discharge lamps, an image signal generator for generating an image signal, and a control circuit for controlling the quantity of light emitted from each discharge lamp in response to the image signal.
摘要:
A first video camera includes a lens barrel, a main frame, a first side panel, a second side panel, a first media insertion part, a viewfinder, a handle part, and a stay. The first media insertion part is fixed to the main frame. The viewfinder is disposed at the upper part of the media insertion part. The handle part protrudes from the viewfinder in a direction parallel to the optical axis of the lens barrel. The stay links the main frame and the handle part. The media insertion part is a separate member from the main frame, the first side panel, the second side panel, the viewfinder, and the handle part.
摘要:
There is provided a grasp member joined to the top portion of an image pickup apparatus body including a lens barrel unit at the front end and a display unit at the rear end through leg portions. Here, the front one of the leg portions is joined to the image pickup apparatus body at an offset position to the left from an optical axis of light incident on the lens barrel unit.
摘要:
An improved scroll type compressor is disclosed. A moveable scroll is eccentrically connected to a rotary shaft and opposed to a fixed scroll for forming a compression chamber. The moveable scroll performs an orbital movement about an axis of the rotary shaft without rotating about its own axis. With the orbital movement, the moveable scroll reduces the volume of the compression chamber and compresses coolant gas therein. A fixed wall is disposed adjacent to the moveable scroll on the opposite side from the fixed scroll. The fixed wall receives a reaction force of the compressed gas applied to the moveable scroll. First elements disposed between the fixed wall and the moveable scroll transmit the reaction force from the moveable scroll to the fixed wall. Second elements are disposed independently from the first elements between the fixed wall and the moveable scroll for determining the orbit of the moveable scroll.
摘要:
A mechanism for allowing the orbital movement of an orbiting scroll with respect to a fixed scroll in a scroll type compressor which prevents the orbiting scroll from rotating around its own axis is disclosed. The orbiting scroll is eccentrically attached to a rotary shaft supported by a housing that encases the fixed and orbiting scrolls. A compression chamber is defined by the interfitting between the orbiting scroll and the fixed scroll. During the course of the orbiting scroll's rotation around the center axis line of a rotary shaft, the volume of a compression chamber decreases as the rotation progresses. Refrigerant gas in the compression chamber is compressed in this manner as the constant volume of gas within the compression chamber decreases in size according to the progression of the rotating spiral member. A balancing weight disposed on the eccentric shaft compensates for dynamic unbalancing generated as the orbiting scroll makes an orbital movement due to the rotation of the rotary shaft. This balancing weight engages a bushing which supports the orbiting scroll. A mechanism for automatically adjusting the radius of the orbital movement is disposed between the rotary shaft and the balancing weight. A spring for restricting the shifting on the eccentric shaft of both the weight and the bushing in the thrust direction is disposed between the weight and the bushing.
摘要:
A variable displacement refrigerant compressor of the variable angle wobble or swash plate type is disclosed. The compressor according to the invention has a displacement control valve which is operable in response to the evaporator pressure so as to restrict the drop thereof by throttling the refrigerant gas flowing through a control port disposed between the evaporator and suction chamber. Crankcase of the compressor is arranged for direct communication with the evaporator so as to keep the crankcase under a pressure which is substantially the same as the evaporator pressure.
摘要:
A variable-delivery refrigerant compressor wherein the delivery of a compressed refrigerant is adjustable by an actuator which is movable with a discharge pressure of the compressor between a first position at which plural discharge valves corresponding to compression chambers are rendered operative, and a second position at which at least one of the discharge valves is rendered inoperative. A pilot switch valve is disposed in a passage through which the discharge pressure is applied to the actuator. The switch valve controls a supply of refrigerant of the discharge pressure to the actuator such that the actuator is placed in the first position while a suction pressure of the compressor is relatively high, and in the second position while the suction pressure is relatively low.