Showing papers on "Contactor published in 1980"

Process and installation for automatic ignition of a plasma cutting torch

Abstract: The invention relates to a plasma cutting plant comprising a principal generator feeding a plasma arc between a workpiece and an electrode of a torch comprising a tube, with initial ignition by means of an ignition or striking arc between the electrode and the tube, via the resistor and the contactor. A circuit comprising a resistor and an excitation coil of a relay is installed across the terminals of the contactor. When the torch has been brought to the correct distance from the workpiece, the circuit detects this correct spacing and acts on the feed motor to stop the latter immediately.

Membrane contact switch

Abstract: A contact switch assembly and method for its manufacture utilizing a resilient dome having electrically conductive surfaces which is positioned on a unitary sheet of plastic or membrane which has a circuit pattern deposited thereon, said circuit pattern forming the contact and contactor means of said switch. In assembly, said membrane is folded upon itself so that the contact and contactor means are positioned in a spaced-apart alignment, separated by said resilient dome, whereby upon depression of said dome, electrical contact is established between said contact and contactor means through the electrically conductive surfaces of said dome.

High-speed automatic tripping contactor

Abstract: A fast opening contactor comprising an electrodynamic repulsion trip device associated to a standard contactor unit so as to operate the contacts towards the open position against the electromagnetic attraction force in response of a short-circuit current.

Auxiliary switch assembly for a power contactor

Abstract: An auxiliary switch assembly for mounting on and operation by a power contactor includes a molded plastic housing cover to be mounted on the contactor by screws which provides a space within the housing for two electrical switches, which for this assembly are standard snap-action switches, and space for a movable element mechanically connected to the actuator of the power contactor which moves within the confines of the housing cover to engage the plunger in each such switch.

Failure protection circuit for a two-motor lift truck

Abstract: An electrically operated dual motor drive system having first and second reversible traction motors (14, 16) driven by a power source (18). Motor control circuitry (10, 12) for controlling the direction of current flow through the motors (14, 16) is designed to be actuated by only two coils (36, 42). Preferably, control circuits (10, 12) employ an arrangement of normally open (32a, 32b, 38a, 38b) and normally closed (34a, 34b, 40a, 40b) contacts such that the two motors (14, 16) operate in reverse directions in the event of a complete system malfunction. A line contactor (20) is advantageously utilized to simultaneously serve as a main power disconnect for a variety of motors within the system.

Preventive system abnormal operation of pump

Abstract: PURPOSE:To prevent an abnormal operation of pump by a system wherein the pump is shut down through a simple circuit comprising an under-current relay, a timer circuit, a counter circuit, etc. when primary current of a motor detected first becomes lower than a set point or pulsative. CONSTITUTION:A motor is checked for primary current with an undercurrent relay UC, which is actuated for occurrence of undercurrent. If this condition lasts longer than a time set on timer UCT, the coil of a main contactor 88 for motor operation is turned off by a contact UCT-b of the timer UCT. Then, where an input current is pulsative, the undercurrent relay UC repeats ON/OFF operation. The number of times for repetition is counted on an electromagnetic counter 6 and where it exceeds a set number of times, a tripping relay is excited, the main contactor 88 is turned off by a contact UCC-b of a tripping relay UCC to stop the motor 1, thus preventing an abnormal operation.

Inspecting method and device for base plate of circuit

Abstract: PURPOSE:To perform tests of continuity and insulation for the base plate of a circuit having an electroconductive pattern at minute intervals by a method wherein an electroconductive contactor capable of moving vertically is made to contact successively with the open end part of the minute part of the electroconductive pattern on the base plate of circuit. CONSTITUTION:After the plate 3d to be inspected being positioned by a guide rail or a guide pin provided at one end of a probe supporting plate, a motor 9 is operated and a probe 2 and the electroconductive contactor 5 are made to contact with the plate 3 to be inspected. At this point of time, continuity inspection between the electroconductive contactor 5 and each probe 2 is started. A cam 10 is rotated at a prescribed angle and a supporting frame 7b is lifted, whereby the contact of the contactor 5 with the plate 3 to be inspected is released. At this stage, insulation inspection between probes 2 is conducted.

Multipolar type circuit breaker

Abstract: A multipolar type circuit breaker has a plurality of breaker element assemblies corresponding to AC source pole number. Each assembly comprises a contact operating mechanism for ON and OFF operations of a movable contactor connected to a load side terminal with respect to a fixed contactor connected to a current source side terminal. A trip mechanism forms an electric current path between the movable contactor and the load side terminal an interlinks with the contact operating mechanism for releasing its normal ON position latch with respect to the movable contactor upon incoming of a excessive curent to arbitrarity trip ON state. The assemblies are housed in a single housing in a mutually parallel and aligning relation. The contact operating mechanisms in all assemblies are operated by a single handle extending transversely to them within the housing. The tripping operation of the trip mechanism in any of the assemblies is synchronously transmitted at a high speed to other assemblies through a single interlinking rod also extending transverse to all the assemblies and holds the handle at a neutral position between its ON and OFF positions.

Arc suppressing means for current limiting circuit breakers

Abstract: Arc suppressing means for current limiting circuit breakers wherein an arc generated between both movable and fixed contacts by an excess current at the time of short-circuiting is magnetically driven by a member extending from the contact part of fixed contactor to an arc running plate in the right angle relation to the plate with a shortened time of arc's staying at the contact part and a shortened time of arc's traveling from the member to a deion grid along the running plate to quickly obtain an elevated arc voltage and to thereby effectively elevate current limiting effect.

Switch with sliding contactor

Abstract: A switch construction including opposed contacts positioned on a base and a bridging sliding contactor slidable between different switch positions. The design of the contacts on the base includes an upper section that defines a first surface engageable by a tab formed on the sliding contactor, and second surface blade portions which provide engagement with wing sections defined on opposite sides of a tab section formed on the sliding contactor. Resilient means press the sliding contactor against this upper section in a fashion such that the wing sections slide over the second surface portions and the tab section engages the first surface portions. The separate engagement of the tab and wing sections provide separate available current paths for the switch; and since either the tab or the wing sections may engage the contact first, arcing is confined to this initial contact area during switch closure. The other section may then act as an inclined plane during switch closure to help lift off the arcing section away from the initial contact area after arcing occurs. The section that is engaged in the maintained state of the switch is thus a clean contact area at which no arcing has occurred. Similarly, upon opening of the switch circuit the initial contact point is also the last point of the sliding contactor that contacts the stationary contact, and thus arcing is again confined to this area.

Power transfer system

Abstract: Disclosed is a method of transferring energy from a stationary generator of power at radio frequencies to a rotating work station such as a coil to heat inductively by selectively connecting the generator as the work station rotates past the generator. A pair of stationary contact strips connected to the generator are used to connect the low voltage, high current radio frequency (RF) energy to the rotating machine. The contact strips are a commutating device in that they can intermittently be connected to a series of brushes or contactors carried by work stations requiring power. The contact strips form a closed loop which shunts the energy at the point where the brushes engage and/or leave the contact strips thereby keeping the current flow to a minimum at those points. As the brushes slide across the contact strips they move from the shunt to the power input points on the contact strips and where the current flow increases because the voltage difference between the strips is the greatest. Consequently, the power can be transferred to the work stations without arcing as the brushes engage or leave the contact strips.

Power interruption protection system for electric motors

Abstract: A power interruption protection system for AC electric motors. An electroresponsive relay (OL) in the energizing circuit of an electroresponsive main power contactor (MC) for an AC motor is responsive to deliberately deenergize the contactor if a power supply interruption persists for more than a few cycles of the supply frequency. A motor current level detector (CLD) monitors the motor current and if it falls below a predetermined level activates a pulse counter (CTR) to register pulses from a clock pulse generator (CPG) which produces pulses each half cycle of the supply frequency. If the pulse counter registers a certain number or more of such pulses an amplifier-driver (AD) energizes the relay to effect disconnection of the motor from the AC supply. The system is disclosed both as a stand-alone system, and as combined in a system affording current overload protection modes as well for AC motors.

Method and apparatus for measuring threeedimentional curvature

Abstract: PURPOSE:To provide an apparatus which allows accurate measurement of three- dimentional curvature extremely complicated by measuring reading of a rotary encorder so arranged to move in the directions of X, Y and Z with a contactor at the tip of an arm having joint pieces rotatively connected to each other. CONSTITUTION:An object with a three-dimentional curvature is retained on a rotary table 11. A shaft 11a is fitted wlth a rotation detecting scale 12 of a rotary shaft (Z axis). A vertical column moves in the X direction with a X axis movement body and in the Y direction with a Y axis movement body. An arm is formed by joint pieces to which are mounted a rotary encoder 7 and a guide roller 8 and a contactor 6 is provided at the tip of the arm 5. Also provided are a control panel 18 for indicating design values and measured values with respect to coordinates of the axes of X, Y and Z, an electronic calculator 19 for collecting measured data and calculating the deviation between the design value computing an actual curvature configuration and a type writer 20 for recording the output.

Method for manufacturing electric switching block of electromagnetic relay

Abstract: Method for manufacturing an electric switching block of an electromagnetic relay wherein a rocking armature end or ends of an electromagnetic block drives respective movable contactor spring plates between opposing fixed contact terminals in respective switching sections of the switching block.

Anti-telegraph control circuit for electromagnet coil

Abstract: An anti-telegraph circuit for locking out the circuit controlling the flow of direct current in a coil winding of an electromagnetically operated switching device, such as a contactor, from an alternating current source whenever improper control voltages are present which would cause repeated operations of the armature picking up and falling out of its sealed position.

Electromagnetic proportional control valve

Abstract: PURPOSE: To enable fluid to be sealed from the open air in safe manner without using a diaphragm by a method wherein a vibration insulating piece is brought into contact with a contactor which moves in synchronism with a plunger to prevent vibration CONSTITUTION: The outer diameter of the contactor 34 is made slightly larger than the clearance L of a vibration insulating piece 35 Therefore, the contactor 34 also takes the same behavior as the plunger 28 in accordance with the vertical motion thereof and suitable sliding resistance occurs in the still vibration insulating piece 35 Said sliding resistance acts to stop the vibration of the plunger 28 Accordingly, the fluid can be sealed from the open air securely without using the diaphragm COPYRIGHT: (C)1982,JPO&Japio

Gas insulated power switch-gear apparatus

Abstract: A gas insulated power switch gear apparatus of a reduced height comprising gas insulated circuit breakers arranged horizontally and disconnecting switches operated vertically is disclosed. Each of the disconnecting switches includes a first sheath portion inserted into an interrupted point of a main bus bar and mechanically connected with the sheath of the main bus bar through an insulating spacer for defining a gas section, and a second sheath portion communicating with the first sheath portion and crossing and extending in the direction perpendicular to the first sheath portion. A collector electrically connected with the conductor of a feeding bus bar is arranged within the second sheath portion, and a movable contactor normally electrically connected with the collector is movable vertically. A fixed contactor electrically connected with the main bus bar conductor and engageable with the movable contactor is arranged within the first sheath portion.

Overcurrent detector for electric circuit

Abstract: PURPOSE:To execute anti-timing operation as to a weak current, by providing an electroconductive magnetic resistor between a contactor and a leg of a U-shaped magnetic circuit member, coupling the resistor to the leg and passing a load current through the magnetic resistor. CONSTITUTION:A load current I, which is detected, flows through an external terminal, contacts 5, 6, a lead wire 6a and a magnetic resistor 7 so that the resistor heats. When the heat generated by the resistor is more than that transferred therefrom, the temperature of the resistor rises gradually. As a result, the magnetic flux density of the resistor 7 and an U-shaped magnetic circuit member 2 falls sharply. When the magnetic flux density falls below a prescribed level, the magnetic attractive force is overcome by the force of a spring 9 so that a contactor 3 is separated from the magnetic circuit member 2, the contact 6 is brought out of touch with the contact 5 and the load current I is cut off. An anti-timing property is thus attained.

Method of variably controlling speed of induction motor

Abstract: PURPOSE:To operate variably at the speed of an induction motor over a wide range by a small capacity inverter by driving the motor in a primary frequency operation in low frequency range and in Scherbius operation in high frequency range. CONSTITUTION:In case of a primary frequency operation, electromagnetic contactors 1, 5 and 9 are closed and electromagnetic contactors 7 and 8 are opened to drive an induction motor in a primary variable frequency operation by a current type inverter 3, and in case of a Scherbius operation, the electromagnetic contactors 1, 7 and 8 are closed, and the electromagnetic contactors 5 and 9 are opened. In such states, the primary power is supplied to the induction motor 6 through the contactor 7, and the secondary power of the motor 6 is regenerated at the power side through the contactor 8, the inverter 3, a transformer 2 and the contactor 1. In this case, the secondary circuit at the inverter 3 side operates as a rectifier, and the primary circuit operates as a power inverter. Since the inverter 3 constitutes at the input side circuit a rectifying circuit by a thyristor, it can control the firing phase to thereby operate the induction motor in a supersynchronous Scherbius operation to largely increase the variable speed range of the motor.

Power measuring apparatus

Abstract: Power measuring apparatus for electric appliances including interconnected male and female connectors for attachment to a source of power and to an appliance to be measured, a transformer having a primary winding in series with one of the conductors interconnecting the connectors, a potentiometer having a resistance element connected with the secondary winding on said transformer and a movable contactor, and an indicator connected between the contactor and one end of the resistance element, the potentiometer being calibrated in terms of cost per kilowatt-hour and the indicator being calibrated in terms of cost per hour.

Starting system for liquefied gas engine

Abstract: PURPOSE:To improve starting property by enlarging a secondary valve opening of vaporizer when cranking up an engine which is cold below a given value. CONSTITUTION:Where an engine temperature is lower than a given value, a contactor 26a of thermal switch 26 is in touch with a vapor phase side contact P, and from closing an ignition switch 24, a vapor phase solenoid 27 is actuated to feed a vapor phase fuel to the engine. Then, a current flows to a relay coil 23a, and a control relay 23 is closed. If the engine is subjected to cranking under the state described, a starting switch 22 is closed, a solenoid-operated valve 16 is excited to increase opening of a secondary valve of vaporizer, and a gas pressure in a secondary chamber is stepped up to increase quantity of the fuel to feed to the engine. Where the engine temperature is kept at the given value or higher, a liquid phase solenoid 28 is actuated and the liquid phase fuel is fed to the engine.

Valve driving device of internal combustion engine

Abstract: PURPOSE:To simplify the construction without cam shaft nor gears for driving suction and exhaust valves in an internal combustion engine, by controlling them through electric detection and function CONSTITUTION:An electromagnet 12a attracts a contactor 12e as it conducts, and a rocking lever 12d is turned in the direction of arrow Y against the elasticity of a valve spring 8 to open an exhaust valve 7 through a push rod 5 The valve is closed when the magnet 12a is deenergized The time for controlling the valve is detected by getting in touch with the contactor and a sensing projection around a shaft fixed to the fore edge of a crankshaft, and the signal is transmitted to a valve motion controller for controlling an actuator 12 The lift of the exhaust valve 7 can be changed in accordance with the level of current added to the electromagnet 12a The similar way is used for controlling the suction valve

Air conditioning equipment

Abstract: PURPOSE:To accomplish comfortable automatic operation control by driving the air conditioning equipment to match life schedules with a program timer connected to the equipment. CONSTITUTION:When a changeover switch 22 is turned to automatic operation, a program timer 23 closes a contact 24 at the set time and a time limiting relay 25 and an auxiliary relay 26 are excited for 2 or 3 seconds. When a pressure switch 3, a thermostat 4 for motor protection 4 and an overcurrent relay 5 for motor protection are closed, an auxiliary relay 6 is energized, and a contact 6a is closed to form a self-holding circuit while an electromagnetic contactor 8 for the pump is energized to operate the pump. When a contact 6a' of the auxiliary relay 6 and a cooling water thermostat 1 are closed, an electromagnetic contactor 2 for the compressor is energized to operate the compressor. In this manner, the air conditioning equipment starts operation. The rest is automatically operated by the program timer 23.

Electric contactor responding to humidity

Abstract: Two contact electrodes (12, 13) separated from one another by an electric insulation are provided which can be electrically connected to one another by wetting the insulation (11). To achieve little delay in the contacting during wetting and optimum adaptability of the contactor to the anatomic conditions of the patient, particularly when the contactor (10) is used in the therapy of enuresis nocturna, the insulation is formed by a flat flexible carrier (11), for example of a plastic fabric, on which two separate conductor systems (12, 13) are attached as contact electrodes. The conductor systems (12, 13) can have the form of intermeshing combs.

Aerial transport system

Abstract: Disclosed is an aerial transport system which comprises an aerial track having therealong a pair of electric current-carrying cables in a parallel relationship with respect to one another and with respect to the track, and self-propelled carriages. Each carriage has an electric current collector to collect electric power from the current-carrying cables and to supply the power to an electrical driving mechanism mounted thereon for driving wheels engaging with the track. The current-carrying cables are separated at longitudinal given intervals so as to define respectively independent electric power supply zones. The transport system further includes a system for controlling electric power supply for the vehicle or carriage including a mechanism for detecting a vehicle or carriage position in the track provided in each power supply zone. The vehicle or carriage position detecting mechanism has a circuit which is closed when the vehicle or carriage is present within the zone, and a detector for detecting an electric current flowing in the zone when the circuit is closed. The detector is associated with a holding relay control circuit. The holding relay controls an electric power supply control circuit having a controlling contactor connected with a contact of the holding relay.

Cut=out circuit for three=phase transformer protection - has three transformers with resistors and thermistor associated with capacitor and solenoid

Abstract: The cut-out circuit is for contactors esp. those providing protection for the low voltage side of polyphase transformers used in electrical power distribution and particularly those employed in rural areas. The cut-out also minimises heating at the contactor proper. Current level and balance in each phase is detected by a current transformer (2, 3, 4) within an insulated housing (1). Each transformer secondary is shunted by a low value resistor (8, 9, 10). The three resistors are spaced symmetrically around a single central heat sensitive element (11). This forms one part of a potentiometer (27, 11) controlling the gate bias of a threshold detecting thyristor or similar semiconductor. The voltage from each resistor also determines the charge on a capacitor (19) via rectifying diodes (13-18) and a further resistive, zener diode potentiometer (20-23) controlling the supply voltage across the thyristor.