160 results about "Binding post" patented technology

The utility model provides a spring-free type bushing end screen, which belongs to the technical field of bushing end screens and comprises a flange seat, an insulating sealing sleeve is embedded in an inner cavity of the flange seat and is clamped in the inner cavity of the flange seat through a locking component, and a locking thread is arranged at the end part, far away from the flange seat, of a binding post along the outer wall. The inner wall of the side, away from the flange hole, of the flange base is in threaded connection with a grounding piece, the grounding piece is arranged outside the locking thread in a sleeving mode, anti-skid lines are arranged on the outer wall of the grounding piece in the circumferential direction, external threads are formed in the bottom of the outer wall of the grounding piece in the circumferential direction, internal threads are formed in the top of the inner wall of the flange base, and therefore the grounding piece is in threaded connection with the top of an inner cavity of the flange base. After the grounding piece is in threaded connection with the flange seat, the end screen is in a continuous grounding state, stable operation of the transformer is guaranteed under the condition that overall stability is guaranteed, and the protection effect is enhanced.

The invention provides a scroll compressor cross ring dynamic strain wireless measuring device, which relates to the technical field of compressor state monitoring and comprises a high-temperature-resistant strain gauge, a wire fixing system and a wireless sensor. Wherein the high-temperature-resistant strain gauges are respectively attached to stress sensitive areas of a static key, a ring beam and a movable key of the cross ring every time; the wire fixing system comprises a three-stage fixing structure formed by an adhesive, an internal wire, an external wire and an internal binding post; the three stages of fixing structures are a strain gauge end fixing structure, a lead transition section fixing structure and a binding post end fixing structure in sequence; the high-temperature-resistant strain gauge is connected with the wireless sensor through an internal wire, a binding post and an external wire, and continuous signal collection is achieved. By implementing operation according to the technical route, the impact load borne by the cross ring at the moment of starting and stopping of the compressor can be collected in a high-quality mode, data collection in a closed cavity is achieved, and an experimental basis is provided for subsequent strength design of the cross ring.

The utility model provides a tensile detection device for a wiring terminal of a drop-out fuse, and relates to the technical field of tensile detection equipment. The flat plate is detachably mounted on the tension detector through bolts, and a first clamping part and a second clamping part are arranged on the flat plate; the driving assembly is arranged on the flat plate and can drive the first clamping part to wrap the connecting position of the wire and the wiring terminal and drive the second clamping part to clamp the wire at the same time, so that the wiring terminal and the wire are synchronously positioned. When the first clamping part is driven to position the wiring terminal part, the second clamping part is driven to synchronously fix the wire part, so that the wiring terminal and the wire can be positioned in one step, the operation steps and the consumed time required for clamping the wiring terminal and the wire by personnel are reduced, the batch detection requirement is met, and the production and detection efficiency is improved.

The utility model discloses a sealed knob switch, which relates to the field of electrical equipment and comprises a shell, a rotating rod, a knob, a rotating block, a base, a second binding post, a contact piece, a first sealing ring, a second sealing ring and a plurality of first binding posts. When the rotary knob is rotated, the rotary knob drives the rotary block to rotate through the rotary rod, the rotary block drives the contact piece to rotate, one end of the contact piece abuts against the second binding post all the time, the other end of the contact piece makes contact with the multiple first binding posts in sequence, and therefore switching of multiple kinds of connection is achieved. In the long-term use process, the first sealing ring plays a dustproof and waterproof role, and the second sealing ring performs secondary protection, thereby improving the sealing performance of the knob switch, prolonging the service life of the knob switch, and preventing water, dust and other impurities from entering the knob switch, causing faults, and further preventing the use effect from being affected.

The utility model relates to a servo motor with a combined iron core structure, which comprises frameworks and a stator iron core, the number of the frameworks is 12, the frameworks are respectively arranged on the stator iron core, a winding is arranged in each framework, doubling conductive pieces are arranged on the 12 frameworks in a staggered manner, and the stator iron core is of a split combined structure. The top of the framework where the doubling conductive part is installed is provided with an insertion groove, the bottom of the doubling conductive part is provided with an insertion rod inserted into the insertion groove, and the top of the doubling conductive part is provided with a binding post. According to the utility model, the doubling conductive members are arranged on the skeleton in a staggered manner, and the winding arranged on the stator iron core is adjusted from conventional 12 split independent winding to four coil continuous winding, so that the subsequent rewiring process is reduced.

The utility model discloses an inverter with a hidden input terminal binding post. The inverter comprises a housing, a binding post, an inverter circuit and an output interface. The outer surface of the shell is provided with two concave parts, the two concave parts are respectively provided with matched cover bodies, the cover bodies cover the corresponding concave parts, and the cover bodies and the corresponding concave parts define a binding post accommodating space; the other end of the positive terminal and the other end of the negative terminal extend out of the shell and are located in terminal containing spaces defined by the two concave parts and the corresponding cover bodies respectively. Each cover body is provided with a wire hole, and each cover body is detachably connected with the concave part. According to the utility model, the concave part and the detachable cover body are arranged, so that the binding post at the input end of the inverter can be effectively hidden and protected, the binding post is prevented from being exposed or protruding out of the outside, and the binding post is effectively prevented from being corroded or impacted to influence the contact performance of the binding post. And the structure of the cover body is optimized, so that the cover body is convenient to disassemble and assemble and is not easy to fall off.

This utility model discloses a power distribution cabinet, including a door panel. The inner side of the door panel is provided with a wiring section and a buffer section. The wiring section includes at least one base fixedly connected to the door panel. At least one wire groove for arranging wires is opened inside the base. At least one terminal block is provided on the base, located near the wire groove. The buffer section includes a buffer plate movably connected to the door panel. This utility model, by setting a base and providing multiple wire grooves on the surface of the base, allows wires to be placed in the wire grooves. The wire grooves protect and restrict the wires, resulting in an orderly arrangement that facilitates later inspection and maintenance by staff, and also ensures the safety of the wires.

The utility model discloses a quick connecting device for motor wires, which comprises a junction box and a box cover, a terminal wire holder is fixed in the junction box, six binding posts are fixed at the top of the terminal wire holder, and the distance between adjacent longitudinal binding posts is equal to the distance between adjacent transverse binding posts. Two first pressing plates and three second pressing plates are arranged at the bottom of the box cover, rubber sheets are fixed to the lower end of each first pressing plate and the lower end of each second pressing plate, the two first pressing plates and the three binding posts on the same side are arranged at intervals, and the three second pressing plates are located among the three binding posts on the two sides and correspond to one another in position; the rubber sheets abut against the tops of the copper sheets connected between the adjacent binding posts, and the box cover is provided with an abutting assembly used for abutting against connecting wires connected with the binding posts. After the box cover is covered, the rubber sheet at the bottom of the first pressing plate or the second pressing plate abuts against the copper sheet so as to ensure the stability of the copper sheet, and the abutting assembly keeps the connection stability of the motor connecting wire.

The utility model discloses an OBC transformer support assembly, which relates to the technical field of transformers and comprises a transformer base, a support body fixedly mounted on the transformer base, a coil arranged in the support body, a transformer cover plate fixedly mounted at the upper end of the support body, and a temperature control switch fixedly mounted in the middle of the transformer cover plate. A wiring mechanism is arranged on the support body and comprises a binding post fixedly installed on the support body, a conductive contact is arranged below the binding post, a trigger mechanism is connected to the conductive contact, a metal gasket and a fixing nut are arranged on the binding post, a butt joint port is formed in the upper end of the conductive contact, and a wiring groove is formed in the bottom of the conductive contact. One side of the wiring groove is provided with a fixing screw. According to the OBC transformer support assembly, through cooperative use of the wiring mechanism and the triggering mechanism, operation of the transformer can be stopped immediately when the coil is in a high-temperature state, and the use safety of the transformer is improved.

The utility model relates to a ground wire pile capable of being automatically locked, which comprises a fixed disc, a circular ring is fixedly arranged on a rear side door of the fixed disc, a binding post is arranged in the circular ring, a wiring pile is arranged at the bottom of the fixed disc, a movable plate is arranged at the top of the fixed disc, and the movable plate is fixedly arranged on the rear side door of the fixed disc. And a rotating assembly and a locking assembly are movably mounted in the fixed disc. According to the ground wire pile capable of being automatically locked, by arranging the locking assembly, when the ground wire pile is used, after a rotating assembly drives a rotating disc to rotate, the rotating disc synchronously drives the position of an arc-shaped sliding groove to change, however, due to the fact that a fixed disc is fixed, the inner wall of the arc-shaped sliding groove pushes the position of a positioning protruding block and the position of a wiring cylinder to change; therefore, the positioning protruding block and the wiring cylinder are contracted outwards, the metal plate is driven to be away from the outside of the binding post, at the moment, a grounding closed state is achieved, and the situation that workers get an electric shock mistakenly during operation and affect life safety is avoided.

The utility model discloses a cold-pressed terminal convenient to install, which comprises a cold-pressed terminal body, the cold-pressed terminal body comprises an installation part and a wiring part, the installation part further comprises an arc-shaped part integrally arranged at the top and a semi-annular sleeve hinged with one side of the arc-shaped part, a spring piece is embedded in one side of the rear part of the arc-shaped part, and the spring piece is connected with the wiring part. A connecting groove is formed in one side of the rear portion of the semi-annular sleeve, one end of the spring piece is arranged in the connecting groove, a clamping groove is formed in the other side of the arc-shaped portion, a clamping block is arranged on the other side of the semi-annular sleeve, and the clamping block is embedded into the clamping groove in a clamped mode. According to the utility model, when the cold-pressed terminal is assembled and disassembled, the nut does not need to be completely screwed off from the binding post, so that the operation efficiency is improved.

The utility model relates to an installation structure of a current transformer. According to the technical scheme, a rectangular notch is formed in the middle of the vertical side wall of a mounting plate, T-shaped inserting grooves are formed in the front surfaces of the left and right plate walls of the rectangular notch, notches are formed in the plate walls in the left and right T-shaped inserting grooves, and shaft sleeves are fixedly arranged on the rear side plate walls at the opposite ends of the left and right notches correspondingly; the clamping assembly comprises clamping blocks which are oppositely arranged left and right, the opposite ends of the left and right clamping blocks are provided with binding post clamping grooves, the middles of the rear side walls of the left and right clamping blocks are fixedly connected with L-shaped bolts, the left and right L-shaped bolts movably penetrate through the corresponding notches respectively, and the bent ends of the left and right L-shaped bolts are sleeved with springs respectively. The pin shafts at the opposite ends of the left and right springs are movably sleeved with wire pressing rings respectively, wire penetrating grooves are formed in the pin shafts at the opposite ends of the left and right wire pressing rings in an up-down penetrating mode, and the opposite ends of the left and right L-shaped bolts are inserted into the left and right shaft sleeves respectively. The beneficial effects of the utility model are that a mutual inductor can be conveniently inserted, and wiring is convenient.

The utility model relates to a switch module, in particular to an electromagnetic switch module, which comprises a box body. The binding posts are fixedly arranged on the box body; the box body is fixedly provided with a wiring sleeve; a static contact is fixedly mounted on the binding post; a sliding rod is mounted in the wiring sleeve in a sliding manner; a movable contact is arranged on the sliding rod; a closing assembly is arranged in the box body; the closing assembly acts to drive the sliding rod to slide in the wiring sleeve so as to drive the moving contact to approach and abut against the static contact. An electromagnetic driving assembly used for driving the closing assembly to act is arranged in the box body, and the electromagnetic driving assembly drives the closing assembly to act, so that an operator can be prevented from being in direct contact with the closing assembly, the safety is improved, and the influence of static electricity carried by the operator on the stability of equipment can be avoided; the closing assembly drives the moving contact to approach and abut against the static contact, power supply can be achieved sensitively, the power-on process is safe, and the power supply process is stable.

The utility model relates to a hand-held portable energy-saving transformer with a universal socket and binding posts. According to the technical scheme, the hand-held portable energy-saving transformer is characterized by comprising a metal shell; a lifting assembly is arranged on the metal shell; a transformer assembly is arranged in the metal shell; a universal socket is arranged on the metal shell; a binding post is arranged on the metal shell; the universal socket and the binding post are electrically connected with the transformer assembly; the portable transformer protection device is convenient to carry, the transformer can be protected conveniently, and meanwhile harmonic waves generated by the transformer can be shielded.

The utility model relates to pipeline anticorrosion technical field, especially a kind of cathodic protection test pile structure, including support pipe;Support pipe inside upper end is equipped with terminal block;The four terminal ends of terminal block back surface are respectively used to be connected with the four detection lines that go up into from the lower end of support pipe, and the two terminal posts of terminal block surface are respectively used to be connected with the terminal pen of multimeter;Support pipe upper end is equipped with the protection cover of barrel shape;The position of support pipe opposite terminal block surface is equipped with let position opening, and the position of protection cover opposite let position opening is equipped with operation opening and is hingedly installed with cover plate;It is equipped with mounting pipe in support pipe, and the inner peripheral wall of mounting pipe has two protruding blocks, and the mounting protruding block formed by protruding on the upper end both sides of terminal block is respectively hung and installed on protruding block;The utility model has the characteristics that terminal block can be more conveniently installed and disassembled, and better sealing effect can be achieved.

The invention discloses a blind connection plug-in assembly structure. The blind connection plug-in assembly structure comprises a plug and a socket, a plurality of groups of moving contacts and static contacts are respectively arranged in the plug and the socket, each moving contact comprises a contact head and a wiring platform which respectively extend out of the plug, a contact spring is arranged in the middle of the contact head and the wiring platform, the outer ends of the contact head and the wiring platform are connected through a flexible connecting belt, each static contact comprises a static confluence sheet, and the static confluence sheet is connected with the wiring platform through a flexible connecting belt. The end face of one end of the static confluence piece is slightly higher than the socket, the other end of the static confluence piece is perpendicularly and fixedly connected with a binding post, the binding post extends out of the socket, protrusions are arranged on the two sides of the plug and the two sides of the socket, opposite connecting holes are machined in the protrusions on the two sides, and locking pieces are installed in the connecting holes. The contact reliability of the movable contact is guaranteed through the spring, each group of contacts and the binding post are isolated through the partition plate to block arc diffusion, and the movable contact and the static contact are simple in structure, so that the plug-in assembly is small in size and low in cost.

The utility model discloses a binding post stable in wiring, which comprises a binding post main body and a threaded hole arranged on the binding post main body, a screw is arranged on the binding post main body, a shifting piece is arranged on the screw, a sliding groove capable of guiding the shifting piece is arranged on the binding post main body, and after a wire head is inserted into the binding post main body, the shifting piece can slide in the sliding groove. The beneficial effects of the utility model are that through the arrangement of the pressing plate and the poking rod, the wire head can be poked to be wound and bent when the screw rotates, and the pressing plate can tightly press the wire head along with the rotation of the screw, so that the contact area between the wire head and the pressing plate is increased; in addition, the antiskid lines arranged on the driving lever and the bumps arranged on the wiring surface are arranged to increase friction with the wire head, so that the driving lever can drive the wire head more conveniently, and the pressing plate can stably press and fix the wire head.

The utility model belongs to the technical field of printed circuit structures, and particularly relates to a circuit connection structure. The field effect transistor comprises a field effect transistor, the bottom surface is a bonding pad, and the side surface is provided with a pin used for controlling the on-off of the field effect transistor; the surface of the aluminum substrate is provided with a surface-mounted bonding pad, and the surface-mounted bonding pad is used for welding a bonding pad on the bottom surface of the field effect transistor; the circuit board is fixed right above the aluminum substrate through a supporting column, and a through hole bonding pad is arranged on the circuit board; after the field effect transistor is welded on the surface-mounted bonding pad on the aluminum substrate, the pin of the field effect transistor extends into the through hole bonding pad of the aluminum substrate after being bent and is connected with the through hole bonding pad in a welding mode. When in use, after the circuit board is connected with a power supply, the pin of the field effect transistor can be used for replacing a binding post to transmit an on-off signal of the field effect transistor, so that the use quantity of the binding post can be reduced, and the tilting risk of the binding post in the aluminum substrate in the reflow soldering process can be reduced.

The utility model relates to the technical field of three-phase voltage transformers, in particular to a three-phase voltage transformer which comprises a three-phase voltage transformer body, a plurality of binding posts are fixedly installed on the surface of the upper end of the three-phase voltage transformer body, and the upper ends of the binding posts are all fixedly connected with bolts. Two connecting frames are fixedly connected to the bottom face of the three-phase voltage transformer body, and two mounting frames are slidably connected to the bottom faces of the two connecting frames. By arranging the auxiliary mechanism, copper sheets or external wires can be conveniently and automatically fixed to the binding posts, and the binding posts can be integrally connected at the same time; according to the three-phase voltage transformer, the working efficiency of wiring of the binding posts or connecting copper sheets is effectively improved, the specific positions of the mounting frame on the bottom surfaces of the two connecting frames can be adjusted according to different mounting positions, the three-phase voltage transformer adapts to different mounting positions, and the three-phase voltage transformer is more flexible to mount and higher in applicability.

The utility model relates to a complete set cabinet detection dolly, which belongs to the high and low voltage electric appliance manufacturing tool technology field, and comprises an upper rack and a lower rack, the end face of the upper rack is provided with a touch screen, the side edge of the touch screen is provided with a plurality of buttons, the upper rack is internally provided with a circuit board which is in circuit communication with the touch screen and the buttons, and the lower rack is provided with a circuit board. A three-phase current source communicated with a circuit board phase circuit is arranged in the lower rack, a rear door is arranged at the rear end of the upper rack and the rear end of the lower rack, a main switch is arranged on the upper portion of the rear door, and a plurality of binding posts A are arranged on the lower portion of the rear door. And a plurality of binding posts B which are distributed in an array manner and are in circuit communication with the circuit board are arranged between the lower part of the rear door and the binding posts A. The device has the characteristics of functional diversity, light structure and good operation stability. The problem of detection convenience of the whole set of cabinets is solved. The detection convenience, efficiency and reliability of the whole set of cabinets are effectively improved, and the detection cost is reduced.

The utility model provides a kind of wiring structure of motor and corresponding motor, wiring structure is arranged at the installation port of the side of shell, the side of the first coil assembly in shell is provided with multiple binding posts, the wiring structure of motor includes terminal housing and fixed housing.Fixed housing is connected on installation port, terminal housing is detachably connected in the installation slot of fixed housing, terminal housing is provided with terminal hole.The wiring post of the wiring structure of motor of the utility model extends into terminal hole, so that external plug can be inserted with terminal housing to realize the electrical connection of motor, and the electrical connection is not easy to damage and fail, the external plug can have different length of lead, and it is convenient to flexibly layout in different use environment.At the same time, terminal housing is detachably connected on fixed housing, so that different models of terminal housing can be replaced to be connected with different models of external plug, and the plug-in compatibility is high, and the terminal housing is also convenient to replace after damage.

The utility model relates to the technical field of motor overload thermal protection, and discloses a motor overload thermal protector which is composed of a protector front cover, a rear cover and a top cover, an overload protection mechanism is arranged in the protector, a reset operation mechanism is arranged on the surface of the top cover, and the overload protection mechanism comprises a heating copper sheet, a binding post, a shifting fork and the like. Current is transmitted to the heating copper sheet through the binding post. When overload occurs, current is increased, so that heat of a heating copper sheet is increased, the heat is transmitted to a deformation copper sheet to deform the deformation copper sheet, related parts are driven to act, a shifting fork pushes a reset copper sheet to trigger a protection mechanism to cut off a circuit, response is rapid, and the safety coefficient is high; a current protection threshold can be set, normal reset and forced reset can be realized, and compared with the prior art, the protector effectively solves the problems of slow overheat detection response, untimely protection mechanism triggering and the like, and can better protect the safe operation of the motor.

The utility model belongs to the technical field of low-voltage electric appliances, and discloses a contactor. The contactor comprises a base body, an upper base, a flexible electric connecting piece and a working coil, wherein a switching conductive piece is arranged in the base body; the upper base is fixed above the base body, the upper base is provided with a wiring terminal, and the upper base is provided with a lead groove for connecting the interior of the base body and the wiring terminal; one end of the flexible electric connecting piece is connected to the wiring terminal, the other end of the flexible electric connecting piece is connected to one end of the switching conductive piece, and at least part of the flexible electric connecting piece is clamped in the lead groove; the working coil is arranged on the outer side of the lower portion of the base body, and the other end of the switching conductive piece is conductively connected with the working coil. According to the contactor, the working coil of the contactor can work more stably, wiring of the working coil is facilitated, and the contactor is suitable for various narrow installation environments.

The three-axis fluxgate sensor comprises a fluxgate sensor body and a protection assembly, the fluxgate sensor body comprises a shell and a connector lug arranged on one side of the shell, the protection assembly comprises an installation block installed on one side of the shell, the installation block is provided with a jack, the connector lug is arranged in the jack, and the connector lug is arranged in the jack. The three-axis fluxgate sensor further comprises a protection plate, the protection plate can block the jacks or move away from the jacks, the front face of the protection plate is provided with a driving inclined face, when the protection plate blocks the jacks, the protection plate can protect the connector lug and prevent external dust and other impurities from entering the connector lug and causing poor contact of the connector lug, and meanwhile the front face of the protection plate is provided with the driving inclined face. When a plug is inserted into the jack, the plug extrudes the driving inclined surface to drive the protection plate to slide linearly, so that the protection plate is moved away from the jack, and the plug can be inserted into the connector lug.

The invention relates to the technical field of electricity teaching aids, in particular to a circuit teaching safety detection device and a using method thereof, the circuit teaching safety detection device comprises a teaching aid, a circuit board is arranged in the teaching aid, at least two binding posts are arranged in the teaching aid, and each binding post is connected with the circuit board. The detection ring is integrated on the conductive part, so that the identification module can automatically identify the identity of the wire according to the identification information of the conductive part when the power connection wire is inserted, the controller drives the electromagnet according to an identification signal, and the locking and releasing states of the telescopic part are finally controlled through magnetic force and the rotating ring; when the telescopic piece is unlocked, the telescopic piece can be contracted, so that the conductive piece and the binding post can be connected to conduct electricity, and therefore, when a student adopts a wrong connection mode in an experiment process, the electricity teaching aid can give out measures correspondingly, the student can correct in time, the learning efficiency of the student is improved, and the teaching efficiency of the student is improved. And equipment faults caused by wrong wiring can be avoided.

The utility model relates to a material receiving device for CNC high-voltage binding posts. The material receiving device comprises a movable seat part, a material receiving disc part, a material receiving rail part, a rotary driving part, an anti-accumulation part and a control part. The material receiving device has the advantages that the anti-accumulation part is arranged on the material receiving disc part, the material receiving disc part is connected with the rotary driving part, the anti-accumulation part can gradually and flatly lay machined parts accumulated at the edge position of the material receiving disc part in the material receiving disc part, and excessive machined parts are prevented from being accumulated at the edge position of the material receiving disc part; in addition, through the arrangement of the material receiving disc component, the material receiving track component, the rotary driving component and the anti-accumulation component, automatic material receiving of the machined parts can be achieved, labor is saved, and efficiency is improved.

The utility model relates to the technical field of transformer production equipment, in particular to a pouring mold for integrally forming a transformer. Comprising a winding mold, the winding mold comprises a top plate, a bottom plate, a plurality of side plates surrounding the peripheral side of the bottom plate and a mounting core column, a winding pouring cavity with an opening in the top is defined by the side plates and the bottom plate, and the top plate is arranged at a cavity opening of the winding pouring cavity; a mounting core column is mounted in the winding pouring cavity, and the mounting core column is connected to the side plate in a sealing manner so as to support a coil main body of the transformer in the pouring process and enable the coil main body to be suspended in the winding pouring cavity; the bottom plate is provided with an overflowing hole for a binding post of the output end to penetrate out. And the output terminal mold is located outside the winding pouring cavity and connected to the bottom plate in a sealed mode, a terminal pouring cavity is formed in the output terminal mold, and the terminal pouring cavity communicates with the winding pouring cavity through an overflowing hole. The casting mold can be formed by one-time integral casting, is fast and convenient, and effectively improves the casting quality.

The utility model belongs to the technical field of motor forward and reverse phase converters, particularly relates to a motor forward and reverse phase converter with a long service life, and aims to solve the problems that working procedures such as plug dismounting are needed when a motor rotates reversely to adjust phase lines for commutation, labor and time are wasted, the service life is shortened or potential safety hazards are generated in the prior art. Comprising a lower end sleeve and an upper top cover, internal wiring pieces are arranged in the lower end sleeve and the upper top cover, and each internal wiring piece comprises a bottom support, a sleeve, a top plate, a binding post and a spring. According to the utility model, when the upper top cover rotates, the internal contact points are connected with different contact points along with the rotation, the state change causes the change of the circuit connection mode so as to realize the interchange of phase lines, and as the phase change is realized through the rotation, the rewiring or the replacement of a socket is not needed, the conversion of the positive and negative rotation of the motor is realized; the purpose of rapidly adjusting forward and reverse rotation of the motor is achieved, the working efficiency is improved, and time is saved.

The utility model discloses a resistance law teaching demonstration teaching aid belongs to teaching aid technical field. The teaching aid includes backplate, is equipped with direct current source, electric bulb, ammeter, voltmeter and various resistances on backplate, and the both ends of each resistance are connected with resistance terminal post. The positive and negative poles of direct current source are connected with the wire with binding jaw, and the wire is connected with electric bulb and ammeter in series, and also can be connected with manual switch in series. Various resistances cover material, thickness, length, short and temperature comparison resistance, and can comprehensively show the influence of different factors on resistance. The voltmeter is used for measuring circuit voltage. Through the teaching aid, the relation between resistance and material, length, cross -section area and temperature can be directly shown, and the bright and dark of electric bulb and the change of ammeter value are matched, help student to understand resistance law, and operation is safe and convenient, and the teaching effect is improved.

The utility model relates to the technical field of electric connectors, and discloses an interference blocking type HDMI electric connector, which comprises a shell, an insulator is fixedly connected to the rear side of the interior of the shell, two metal woven meshes are fixedly connected to the front side of the interior of the shell, aluminum foils are fixedly connected to the interiors of the two metal woven meshes, and the aluminum foils are fixedly connected to the interiors of the two metal woven meshes. A terminal is fixedly connected to the front side of the interior of the insulator, a connector lug is fixedly connected to the rear side of the shell, guide grooves are formed in the upper side and the lower side of the interior of the shell, and a protection mechanism is arranged at the top of the shell and used for protecting the terminal. According to the utility model, the insulator blocks signal interferences of different lines and ensures stable transmission of signals, the housing constructs an electromagnetic shielding space, the metal woven mesh guides interference signals to the ground and prevents internal signal leakage, the aluminum foil strengthens low-frequency interference shielding, and the guide groove reduces interferences caused by unstable connection. Therefore, accurate, efficient and interference-free signal transmission is ensured.