1805results about "Contacts" patented technology

A DC relay for anti-short circuit current and arc extinction includes two static contact leading-out ends, a movable contact piece in a straight sheet type, a pushing rod assembly, a fixed upper yoke, a follow-up yoke and a lower armature. The fixed upper yoke is fixed above the movable contact piece, corresponding to a position between the two movable contacts. The follow-up upper yoke is fixed on the pushing rod assembly, above the movable contact piece, corresponding to a position between the two movable contacts. The lower armature is fixed on a bottom end face of the movable contact piece. The fixed upper yoke, the follow-up upper yoke and the lower armature are respectively arranged in a width direction of the movable contact piece, and two magnetic conductive loops are formed in the width direction of the movable contact piece.

A portable computer includes a display portion comprising a display and a base portion pivotally coupled to the display portion. The base portion may include a bottom case and a top case, formed from a dielectric material, coupled to the bottom case. The top case may include a top member defining a top surface of the base portion and a sidewall integrally formed with the top member and defining a side surface of the base portion. The portable computer may also include a sensing system including a first sensing system configured to determine a location of a touch input applied to the top surface of the base portion and a second sensing system configured to determine a force of the touch input.

A relay includes a pair of static contact leading-out terminals; a plurality of movable contact pieces, two ends of each of the movable contact pieces along a first direction is configured to contact with or separate from the pair of static contact leading-out terminals; the first direction is an arrangement direction of the pair of static contact leading-out terminals; wherein a contact gap between at least one of the plurality of movable contact pieces and the static contact leading-out terminal is smaller than contact gaps between remaining movable contact pieces of the plurality of movable contact pieces and the static contact leading-out terminal; and an anti-short circuit structure for forming suction forces on the plurality of movable contact pieces in a contact closing direction; wherein the suction force on the movable contact piece with a smaller contact gap is smaller than the suction forces on the remaining movable contact pieces.

The contactor comprises an electromagnetic assembly, a static contact and a movable assembly, the movable assembly comprises a movable contact, a first elastic part and a driving part which are connected, and the first elastic part is configured to generate elastic force supporting the movable assembly; the driving component is configured to generate electromagnetic driving force through a magnetic field generated by the electromagnetic assembly, and the controller is configured to control a movable contact and a static contact of the movable assembly to be closed and respond to the fact that the sensor detects that the driving component generates displacement based on electric repulsive force generated by current flowing through the movable contact and the static contact. And controlling the electromagnetic assembly to adjust the generated magnetic field so as to reduce electromagnetic driving force which is generated by the driving part according to the generated magnetic field and is opposite to the electric repulsive force, so that the movable contact is not closed with the static contact again. According to the contactor disclosed by the invention, fusion welding of the movable contact and the static contact in the short circuit process can be prevented, so that the contactor fault is avoided, and the equipment reliability is improved.

A relay includes a pair of static contact leading-out terminals; a movable contact assembly including a movable contact piece are configured to contact with or separate from the pair of static contact leading-out terminals along a first direction; the movable contact assembly has a first and a second side surfaces along a third direction; wherein a moving direction of the movable contact piece, the first direction, and the third direction are perpendicular with each other; a push rod assembly including a contact bracket; the contact bracket has a first side wall corresponding to the first side surface and a second side wall corresponding to the second side surface along the third direction; and an anti-rotation structure including a first anti-rotation piece located between the first side wall and the first side surface and a second anti-rotation piece located between the second side wall and the second side surface.

The invention relates to a method for preparing a carbon nanotube reinforced copper-silver-based electrical contact composite material based on a liquid phase atomization method, and belongs to the technical field of electrical contact preparation. The preparation method comprises the following steps: carrying out hot pressed sintering on mixed powder of reinforcement powder, copper powder and silver powder, solidifying the powder to form an Ag-coated CNTs / Cu-Ag composite material block, and then preparing the Ag-coated CNTs reinforced Cu-Ag-based electrical contact composite material through a process route of solid solution, extrusion and aging. The preparation method disclosed by the invention is simple to operate and stable in preparation process, and the mechanical and electrical properties of the prepared composite material can respectively reach 157HV and 103% IACS (International Annealed Copper Standard) and above; according to the method, ablation and damage of the surface of the electrical contact in the working process are relieved, the viscosity of a molten pool is increased, the contact resistance in the electrical contact process can be reduced, the current concentration phenomenon and the temperature rise effect at a contact point can be relieved, the mass loss of an electrical contact material is reduced, the maintenance cost is reduced, and the method has good application prospects in the field of electrical contact materials.

A contact unit and a rotary isolation switch. The contact unit comprises a housing and a contact mechanism provided in the housing, wherein the contact mechanism comprises a pair of stationary contact assemblies and a moving contact assembly, each stationary contact assembly comprising a stationary contact portion; arc-extinguishing systems are provided on either side of the contact mechanism, each arc-extinguishing system comprises an arc-extinguishing cover, one end of which serves as an arc inlet; the contact mechanism further comprises a shell, which has an accommodating cavity provided with two opposite openings, each opening being connected to one arc inlet; and the moving contact assembly and the stationary contact portions are mounted into the accommodating cavity, the moving contact assembly is located between the pair of stationary contact portions, and the contact mechanism and the arc-extinguishing systems on the two sides jointly form a relatively closed space. In the present invention, the contact mechanism and the arc-extinguishing systems on the two sides jointly form the relatively closed space, such that the arc generated by the contact mechanism flows in the relatively closed space, thereby improving the arc-striking and arc-quenching effects.

The invention relates to the technical field of load switches, in particular to a load switch and a ring main unit thereof, the load switch comprises a cabinet body, a cabinet door, a support frame, a sleeve, a static contact and a moving contact, the cabinet door is hinged to the cabinet body, the support frame is fixedly connected with the inner wall of a shell, both the sleeve and the static contact are fixedly connected with the support frame, and a control rod is further hinged to the support frame; the movable contact is slidably connected to the sleeve, one end of the movable contact is hinged to the control rod, a spray head is fixedly installed in the sleeve, and a plurality of first cleaning pipelines and second cleaning pipelines are arranged in the spray head. The cleaning assembly cleans carbon deposits on the surfaces of the moving contact and the static contact, and the problems that the contacts are powered off due to carbon deposits on the contacts, an electric appliance cannot work normally, and the service life of the electric appliance is shortened are solved.

A relay includes a movable contact assembly comprising a movable contact piece; a push rod assembly configured to push the movable contact assembly to move, to make the movable contact piece contact with or separate from a static contact leading-out terminal; a limiting component connected to the movable contact assembly and the push rod assembly, and configured to restrict the movable contact assembly from rotating around an axis of the push rod assembly relative to the push rod assembly; and an elastic assembly configured to provide a contact pressure.

A system includes a circuit protection device (CPD) having an input coupled to an aircraft power generator and an output coupled to an aircraft electrical load. A shorting switch is coupled to the input of the CPD. The shorting switch, when closed, provides a fault current path that returns to the aircraft power generator and avoids passing through the CPD and the aircraft electrical load. A controller, based upon the voltage measurements from one or more voltage sensors and current measurements from at least one current sensor selectively opens and closes one or more of the CPD and the shorting switch.

The invention discloses an integrated sealed primary and secondary fusion pole-mounted circuit breaker in the technical field of circuit breakers, and the integrated sealed primary and secondary fusion pole-mounted circuit breaker comprises a case, a push-pull mechanism, a first elastic mechanism and a second elastic mechanism. A plurality of sets of insulating pull rods extending into the circuit breaker body are installed in the case in an up-down sliding mode, the push-pull mechanisms are fixedly installed in a plurality of sets of supports in the case in a rotating mode, and the top ends of the push-pull mechanisms are fixedly connected with the bottom ends of the insulating pull rods. The two sides of the support are symmetrically provided with two groups of first elastic mechanisms connected with the push-pull mechanism, and the problems that the speed of a movable contact block in an existing circuit breaker cannot be effectively buffered when the movable contact block rapidly gets close to or gets away from a static contact block, and the elastic mechanisms in the circuit breaker are inconvenient to efficiently synchronize energy storage and pressure release of a closing spring and an opening spring; and the operation efficiency, the reliability, the synchronism, the arc extinguishing performance and the like of the circuit breaker are not improved.

A micro-electrical-mechanical-system (MEMS) switching device including a first MEMS switch having a first and second terminal, and a second MEMS switch having a third and fourth terminal. The device also includes first and second input conductors, and first and second output conductors. The first input conductor electrically connects the second terminal to the third terminal. The second input conductor electrically connects an input port to the first input conductor. The first output conductor electrically connects a first output port to the first terminal. The second output conductor electrically connects a second output port to the fourth terminal. A first path from the input port to the first output port, and a second path from the input port to the second output port, have substantially identical electrical characteristics.

The invention relates to the technical field of power equipment, in particular to a vacuum pole-mounted circuit breaker, which comprises a vacuum arc-extinguishing chamber and a mechanism box, a static contact and a moving contact are inserted in the vacuum arc-extinguishing chamber, and under the action of the mechanism box, the moving contact can be close to or far away from the static contact and can be conducted with the static contact; a conductive part is arranged between the static contact and the moving contact, the conductive part can generate elastic deformation, can be in stop fit with the static contact or the moving contact, and is configured to be conducted with the static contact and the moving contact before the static contact and the moving contact are conducted. Therefore, the problem of arc erosion between the static contact and the moving contact is effectively avoided in a mode of transferring an arc generation position, the bounce amplitude of the moving contact is reduced by utilizing the elastic deformation characteristic of the conductive part, the service life of the static contact and the moving contact can be ensured while the wear of the static contact and the moving contact is reduced, and the service life of the static contact and the moving contact is prolonged. And the conductivity between the static contact and the moving contact can be ensured.

The invention discloses a draw-out type switch cabinet, and particularly relates to the technical field of switch cabinets, the draw-out type switch cabinet comprises a cabinet body, a plurality of drawer chambers distributed at intervals up and down are arranged in the cabinet body, the rear end of each drawer chamber is provided with a static contact mounting substrate, a drawer is slidably connected in each drawer chamber, and the rear end of each drawer is provided with a moving contact mounting substrate. Through the arrangement of the drawing assembly, on one hand, when the drawer is inserted into the drawer chamber, repulsive force is generated between the second electromagnetic part and the permanent magnet part, a buffering effect on insertion of the drawer is achieved, the drawer is prevented from colliding with the cabinet body, meanwhile, too large force generated when the contacts are inserted can be avoided, and abrasion between the contacts is reduced; and when the drawer is drawn out of the drawer chamber, the extrusion block can be synchronously drawn out of the limiting sliding groove, so that the second electromagnetic part gradually moves upwards in the limiting sliding groove under the springback effect of the second elastic piece, repulsive force is generated again corresponding to the position of the permanent magnet part, and the power assisting effect is achieved on drawing of the drawer.

The utility model discloses a primary and secondary fusion outdoor pole-mounted circuit breaker, which belongs to the technical field of circuit breakers, and comprises a mounting rack, an operating mechanism mounted at the top of the mounting rack, a plurality of vacuum circuit breakers mounted at the top of the operating mechanism, and the operating mechanism used for driving the vacuum circuit breakers to open and close. A plurality of insulators I and insulators II are fixedly mounted at the top of the mounting frame, a group of knife switch assemblies are arranged at the tops of the insulators II, closing assemblies are arranged at the tops of the insulators I, and fixed knife switches and movable knife switches are mounted on brake bars in the knife switch assemblies; a plurality of telescopic springs are installed between the fixed disconnecting link and the movable disconnecting link to push the movable disconnecting link outwards, so that the movable disconnecting link can be tightly attached to an abutting plate on a brake base during closing, electric arcs caused by poor contact due to structure looseness after long-time use are prevented, and the use safety is improved.

The invention relates to the technical field of computational material science, in particular to a high-entropy ceramic phase change strengthened silver-based electric contact material component screening method, which comprises the following steps of: firstly, based on first principle calculation and Monte Carlo molecular dynamics simulation, combining experimental data correction, and screening out a (MgCoNiCuZn) O component proportion of which the phase change temperature is close to a silver melting point and the single-phase enthalpy value is high; secondly, dynamically simulating wetting behaviors of liquid silver and O with different component proportions (MgCoNiCuZn) through molecular dynamics, and selecting a component proportion with the best wettability with the liquid silver in combination with phase boundary energy calculation and wetting angle experimental verification; and finally, preparing a sample based on spark plasma sintering, actually measuring a wetting angle by using a seat drop method, and feeding back and correcting simulation parameters to form closed-loop optimization. The method is suitable for wettability collaborative optimization screening of a rare earth element doped high-entropy oxide system and liquid metal, proper components can be efficiently and accurately screened out, and the performance of the silver-based electric contact material is improved.

According to one embodiment of the present disclosure, a vacuum circuit breaker may include: a pressure vessel filled with an insulating gas of a predetermined pressure; a vacuum interrupter provided inside the pressure vessel and having a fixed electrode and a movable electrode in a vacuum tube in a vacuum state; a bellows provided to seal a gap between the vacuum tube and the movable electrode; a movable rod, one end of which is connected to an end portion of the movable electrode via an insulating link, and which is capable of penetrating the pressure vessel and reciprocating in an axial direction while maintaining airtightness; a drive rod which is provided outside the pressure vessel at the other end of the movable rod and which transmits the driving force of the drive unit to the movable rod; and a contact pressure spring, one end of which is supported by the movable rod and the other end of which is supported by the driving rod, in which a ratio of a self-closing force of the vacuum interrupter to a minimum closed contact pressure is set to a predetermined ratio.

The invention discloses a moving contact applying a comb-shaped contact finger structure and a clamp type disconnecting switch, relates to the technical field of disconnecting switches, and is used for solving the problem that the existing clamp type disconnecting switch is concentrated due to clamping force or stress. The moving contact comprises a push plate, supporting pieces, a contact finger, a clamping spring and a mounting plate, the end part of the push plate is connected with one end of the supporting piece on the corresponding side through a connecting plate, the other end of the supporting piece is hinged with the mounting plate, one end of the supporting bent plate is hinged with the mounting plate, and the other end of the supporting bent plate is hinged with the clamping spring. The clamping spring is located between the supporting piece and the other end of the supporting bent plate. The two groups of contact fingers are symmetrically arranged between the two supporting bent plates, one end of each contact finger is fixedly connected with the supporting bent plate on the corresponding side, and the other end of each contact finger is in a comb tooth shape and is used for being in contact with a static contact; one end of the pressing plate is fixedly connected with the other end of the supporting bent plate, and the other end of the pressing plate is contacted with the other end of the contact finger from the inner side. Reliable clamping force exists between the clamping device and the static contact.

The utility model belongs to the technical field of electromagnetic switches, and particularly relates to an electromagnetic switch with an indicating lamp, which comprises a bottom shell, a top cover, a closing button, an opening button, the bottom shell and a contact pin seat assembled by a buckle, a first contact pin and a second contact pin are assembled on the contact pin seat, and an electromagnetic coil is assembled on one side of an inner cavity of the bottom shell through a mounting frame. A moving seat is assembled on the contact pin seat in a sliding mode, a movable contact plate is arranged on the moving seat through a first spring, the warped plate drives the moving seat to move up and down in a reciprocating mode when swinging, connection and disconnection of the first contact pin and the second contact pin are achieved, a second spring is connected between the moving seat and the top cover, and a sleeve seat is arranged on the top cover. The second lead is propped against the second contact pin through a third spring in the sleeve seat; according to the utility model, the contact pin seat and the bottom shell are assembled in a buckling manner, so that quick disassembly and reassembly during maintenance are facilitated, the electromagnetic switch does not need to be integrally disassembled, the maintenance time and cost are greatly saved, the electrical connection is more reliable, and the stability and durability of the whole structure are improved.

The invention relates to the technical field of circuit breaker isolation switch equipment, and discloses a circuit breaker isolation switch of a primary and secondary fusion ring main unit, which comprises a mechanism box body, an installation space is arranged in the mechanism box body, and the top of the mechanism box body is fixedly connected with a plurality of airtight insulators. According to the invention, when the contact piece is arranged and the disconnecting switch part needs to be switched on, the operation switch is firstly rotated reversely, the rotating shaft rotates to drive the connecting contact at one end of the isolating rod at one end of the operation insulator to approach, and the connecting inclined block is arranged to be inclined, so that the collision phenomenon caused by inaccurate alignment of the isolating rod and the connecting contact can be avoided; the isolating rod is aligned and connected with the connecting contact, so that the connecting contact is protected from being damaged due to collision between the connecting contact and one end of the isolating rod on one hand, and the butt joint accuracy of the connecting contact at one end of the isolating rod on the other hand is improved on the other hand.

To prevent upsizing of an electromagnetic relay while reducing an impact on the operation of an auxiliary contact part by a main contact part.SOLUTION: An electromagnetic relay comprises a base, a first fixed terminal, a first fixed contact, a second fixed terminal, a second fixed contact, a main contact part, a coil part, an auxiliary contact part, and a second moving member. The main contact part includes a movable contact piece, a first movable contact, a second movable contact, and a first moving member. The movable contact piece extends in a lateral direction. Between a first closed position and a first open position, the first moving member is movable in a moving direction perpendicular to the lateral direction. The main contact part is supported by the base in a supporting direction perpendicular to the lateral direction and the moving direction. The coil part is supported by the base in the supporting direction. The auxiliary contact part includes an auxiliary fixed terminal, an auxiliary movable terminal, and an auxiliary movable contact. In the moving direction of the first moving member, the auxiliary contact part is disposed opposite to the main contact part with respect to the coil part. The second moving member moves in the moving direction in conjunction with the first moving member.SELECTED DRAWING: Figure 2

The invention discloses a silver-based tin oxide electric contact material and a preparation method thereof, and relates to the technical field of electric contact materials. When the silver-based tin oxide electric contact material is prepared, firstly, a high-temperature solid-phase method is used for doping lithium and cerium to prepare doped tin oxide powder; stannic chloride and copper nitrate are prepared into a fiber membrane through electrostatic spinning, meanwhile, titanium dioxide is grown in situ through nano spraying, and doped stannic oxide fibers are prepared after calcination; the doped tin oxide powder, doped tin oxide fibers and silver powder are subjected to high-energy ball milling and powder mixing and then annealed, and silver-based tin oxide composite powder is obtained; the silver-based tin oxide composite powder is subjected to pre-pressing forming and then subjected to vacuum discharge plasma sintering, and the silver-based tin oxide electric contact material is prepared. The prepared silver-based tin oxide electric contact material has the advantages of being low in resistivity, high in fusion welding resistance, good in arc erosion resistance and easy to machine and shape.

The invention discloses a relay, which comprises a pair of static contact leading-out ends, a plurality of movable reeds and a plurality of separators, two ends of each movable reed along the first direction are respectively contacted with or separated from the leading-out ends of the pair of static contacts; the first direction is the arrangement direction of the pair of static contact leading-out ends; the moving direction of the movable contact spring is defined as a second direction; the number of the separators corresponds to the number of the movable reeds. Each separator comprises a top part and two side parts, the top part is located on one side, facing the static contact leading-out end, of the movable contact spring, and the two side parts are connected to the two sides, in the third direction, of the top part respectively and extend in the direction away from the static contact leading-out end from the top part; and the two side parts of the separator are respectively positioned on the two sides of the same movable contact spring along the third direction. Wherein the first direction, the second direction and the third direction are perpendicular to one another.

The invention discloses a quick closing operation mechanism of a circuit breaker, which comprises a shell, a handle, a static contact supporting piece, a moving contact supporting piece, a linkage piece and a tripping mechanism, and is characterized in that the handle and the moving contact supporting piece are rotationally arranged in the shell, a contact torsion spring is arranged between the shell and the moving contact supporting piece, the moving contact supporting piece is provided with a long circular hole, and the linkage piece is arranged in the long circular hole; a pin shaft is arranged in the shell and penetrates through the oblong hole, and the moving contact supporting piece rotates relative to the pin shaft; an installation area is arranged in the shell, the energy storage limiting piece slides and is limited in the installation area, the handle is provided with a moving area, the moving contact supporting piece is provided with an abutting portion, and the energy storage limiting piece is provided with a moving portion limited in the moving area and a matching portion. And in the last section of closing action, energy storage is realized based on the energy storage limiting piece, oxide between the moving contact and the static contact can be quickly broken down, and the overall closing effect is improved.

The invention provides a graphene reinforced copper-based electrical contact material and a preparation method thereof. The electrical contact material comprises the following raw materials in percentage by mass: 15-35% of tungsten powder, 1-10% of chromium powder, 1-5% of molybdenum powder, 0.1-1% of cerium oxide powder, 0.5-2% of copper-based graphene powder and the balance of copper powder. According to the graphene reinforced copper-based electrical contact material and the preparation method thereof, surface copper-based treatment is carried out on graphene, so that the problems that the interface infiltration between graphene and copper is poor and the copper is easy to oxidize are effectively solved, and the obtained electrical contact material has excellent mechanical property, conductivity, oxidation resistance and the like.

The invention discloses a 10KV sulfur hexafluoride switch cabinet which comprises a cabinet body, a gas box is arranged in the cabinet body, a mechanism chamber is arranged on the gas box, an electric control chamber is arranged on the mechanism chamber, an operating mechanism is arranged in the mechanism chamber, a three-phase high-voltage switch assembly is arranged in the gas box, and the three-phase high-voltage switch assembly is connected with the operating mechanism. A wire inlet sleeve and a wire outlet sleeve which are matched with each phase of high-voltage switch assembly are arranged on the gas box, the wire inlet sleeve is arranged on the gas box in an inverted mode, a first cylindrical contact is fixedly arranged in the wire inlet sleeve in a sleeved mode, copper-tungsten alloy of a spiral structure is embedded in the inner circumferential wall of the first cylindrical contact, a copper wire inlet rod is vertically inserted in the first cylindrical contact, and a wire outlet rod is arranged on the wire inlet sleeve. A heat dissipation box is arranged at the upper end of the gas box, a pressure relief device is arranged at the upper end of the heat dissipation box, the heat dissipation box and the gas box are internally communicated to form a closed cavity, the closed cavity is filled with sulfur hexafluoride gas, an inflation and measurement integrated pressure gauge is mounted on the gas box, and heat dissipation fins are paved on the outer surfaces of the gas box and the heat dissipation box. The heating value can be reduced, efficient heat dissipation is achieved, and the reliability of the switch cabinet is improved.

In accordance with an embodiment, a microelectromechanical system (MEMS) switch device includes: a substrate; a switching membrane disposed above the substrate; a pull-in electrode disposed above the switching membrane; a metal contact disposed on the switching membrane; and a pull-back electrode disposed below the switching membrane, wherein the switching membrane is movable between an open position and a closed position, and wherein in the closed position, the metal contact electrically connects two RF signal lines.

The invention discloses a contactor moving terminal assembly and a contactor. The contactor moving terminal assembly comprises: a moving terminal; the driving shaft is movably connected with the movable terminal and is used for driving the movable terminal to move from the open position to the closed position; the main elastic piece is axially compressed between the bottom of the movable terminal and the driving shaft and is used for providing main contact pressure for the movable terminal; and an auxiliary elastic member disposed between the moving terminal and the driving shaft. When the movable terminal is in the closed position, the auxiliary elastic piece is axially compressed between the bottom of the movable terminal and the driving shaft and is used for providing auxiliary contact pressure for the movable terminal; and when the movable terminal is in the disconnection position, the auxiliary elastic piece is not axially compressed. According to the invention, the main elastic member and the auxiliary elastic member apply the contact pressure to the moving terminal at the same time, so that the contact resistance between the moving terminal and the static terminal is reduced, the short-circuit current resistance of the contactor is improved, and the auxiliary elastic member does not affect the normal pull-in of the contactor.

The invention provides coated SnO and FeOx composite oxide powder and a silver-based composite electric contact material and a preparation method thereof, and the preparation method comprises the following steps: providing stannous mono-sulphate, dissolving, stirring to form a SnSO4 solution, and continuously reacting to obtain a solution A; adding an alkaline reaction solution into the solution A to reach a preset pH value to obtain a precursor solution; performing hydrothermal reaction on the precursor solution; washing and drying a hydrothermal reaction product to obtain SnO powder; the preparation method comprises the following steps: adding FeSO4 or FeCl2 into an aqueous solution containing SnO powder, dissolving, adding H2C2O4 to obtain a precipitate, filtering, separating, and drying; and carrying out vacuum heat treatment on the precipitate to obtain the coated SnO-coated FeOx composite oxide powder. The SnO-coated FeOx composite oxide with a controllable and adjustable valence structure can be formed, and the composite oxide is firstly applied to the field of silver-based composite electric contact, so that the Ag / SnO-coated FeOx composite electric contact material has the performance advantages of low temperature rise, long cycle life and the like in the service process.

The invention relates to the technical field of electrical contact materials, and particularly discloses a graphene modified electrical contact material and a preparation method thereof, and the preparation method comprises the following steps: preparing a polydopamine-graphene suspension; adding a copper-containing solution into the polydopamine-graphene suspension to prepare a polydopamine / copper modified graphene material; the preparation method comprises the following steps: carrying out ball-milling mixing on the following components in percentage by mass: 1-4% of a polydopamine / copper modified graphene material, 0.03-0.2% of aluminum powder, 0.3-0.8% of zirconium powder, 15-20% of copper powder and the balance of tungsten powder to obtain a mixture; the mixture is subjected to pressure forming and sintering, and the graphene modified electrical contact material is obtained. According to the preparation method, the graphene is modified, the dispersity and wettability of the graphene are improved, copper, tungsten, aluminum, zirconium and the modified graphene are compounded, and all the components act comprehensively, so that the comprehensive properties such as the mechanical property, the conductivity and the ablation resistance of the electrical contact material are improved.