CN214542038U - Movable anti short circuit direct current relay - Google Patents

Abstract

Disclosed is a movable short-circuit resistant direct current relay, which comprises a shell, a magnetic pole plate, an upper shielding cover, a first magnetic conduction block, a second magnetic conduction block, two fixed contacts, a lower shielding cover, a movable contact bridge and a pushing component, wherein the top of the pushing component is connected with the movable contact bridge and used for pushing the movable contact bridge to be communicated with or disconnected from the two fixed contacts, the lower shield of the relay includes an elastic connecting member having a certain stroke, the elastic connecting member absorbs tolerance when the housing and the magnetic pole plate are welded, can ensure the stable contact and fitting of the upper shield and the lower shield, when the relay is electrified with large current, the two magnetic conduction blocks form a magnetic conduction loop, the attraction force generated between the two magnetic conduction blocks is larger than the elastic force of the lower shield, so that the opening distance of the two magnetic conduction blocks is reduced, the attraction force is increased, therefore, the movable contact bridge can be well kept in suction with the two fixed contacts, and the working stability and the short-circuit resistance of the relay are greatly improved.

Description

Movable anti short circuit direct current relay

Technical Field

The utility model relates to a relay technical field, concretely relates to movable anti short circuit direct current relay.

Background

The conventional structure of a direct current relay in the current market comprises a shell, two static contacts, a movable contact bridge and a driving mechanism, wherein the two static contacts are installed in the shell, the movable contact bridge and the two static contacts are vertically and oppositely arranged, the driving mechanism is provided with a sleeve, a static iron core, a movable iron core, a push rod group and a counter-force spring, the sleeve is arranged below the shell, the movable iron core is movably arranged in the sleeve, the static iron core is fixed above the movable iron core, a gap is formed between the static iron core and the movable iron core, the push rod group is vertically arranged, the lower end of the push rod group is tightly penetrated in the movable iron core in a matching manner, the upper part of the push rod group is connected with the movable contact bridge, and the upper part of the push rod group is further sleeved with a contact spring which is positioned below the movable contact bridge and used for supporting the movable contact bridge and a stop sheet which is positioned above the movable contact bridge and used for stopping the movable contact bridge; the counter-force spring is sleeved outside the lower part of the push rod. When the sleeve is electrified, a magnetic field is generated, a magnetic potential difference is generated between the movable iron core and the static iron core, the movable iron core moves upwards, and then the movable contact bridge is driven to move upwards, so that the movable contact bridge is respectively attracted and communicated with the two static contacts.

When the movable contact bridge is respectively attracted, communicated and electrified with the two static contacts, as the contact flow guide channel of the movable contact bridge and the two static contacts is very small, an electric repulsion force can be formed, the larger the electrified current is, the larger the electric repulsion force borne by the movable contact bridge is, and thus, the contact pressure can be reduced, and even the movable contact bridge and the static contacts can be flicked. At present, the movable contact bridge and two fixed contacts are ensured to be attracted by enhancing the spring force value of a contact spring. However, the force value of the contact spring is too strong, which will affect the operations of the driving mechanism such as reset, and reduce the stability of the relay.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model provides an anti short circuit direct current relay of movable sets up the magnetic conduction piece respectively through the upper and lower at the movable contact bridge for form closed magnetic conduction return circuit in the magnetic field that the movable contact bridge overflows and produces, two magnetic conduction pieces produce suction and drive the movable contact bridge rebound, thereby can fine assurance movable contact bridge and two static contacts keep the actuation, have promoted relay job stabilization nature and anti short circuit ability greatly.

An embodiment of the utility model provides an anti short circuit direct current relay of movable, the relay includes:

the shell and the magnetic pole plate surround to form an accommodating cavity;

the upper shielding cover is movably arranged in the accommodating cavity;

the first magnetic conduction block is fixedly arranged at the top of the inner side of the upper shielding cover;

the two static contacts are fixedly connected with the shell and penetrate through the shell and the upper shielding cover;

a lower shield positioned between the upper shield and the pole plate;

the movable contact bridge is positioned below the two fixed contacts and between the lower shielding case, and the two movable contacts of the movable contact bridge correspond to the two fixed contacts;

the top of the pushing component is connected with the movable contact bridge to push the two movable contacts of the movable contact bridge to be connected with or disconnected from the two fixed contacts;

the second magnetic conduction block is fixedly connected with the movable contact bridge and is arranged opposite to the first magnetic conduction block, and the first magnetic conduction block and the second magnetic conduction block form a magnetic conduction loop so that the second magnetic conduction block drives the movable contact bridge to move upwards;

the lower shielding cover comprises an elastic connecting piece extending to the outer side of the bottom surface of the lower shielding cover, and the elastic connecting piece enables the upper shielding cover to drive the first magnetic conduction block to move so as to adjust the distance between the first magnetic conduction block and the second magnetic conduction block through elastic deformation.

Further, the pushing assembly partially extends out of the lower shield cover and the magnetic pole plate, a coil is arranged on the outer side of the pushing assembly, and the coil is configured to be attached to the bottom of the shell and the lower shield cover according to the elastic force of the elastic connecting piece when the coil is not electrified.

Further, the bottom surface of the lower shielding cover is upwards sunken to form at least two grooves;

lower shield cover include with the recess one-to-one elastic connecting piece, elastic connecting piece includes that connecting plate and two settings are in the elasticity lateral wall of connecting plate both sides, the connecting plate with the recess bottom is connected with the detachable mode, two the elasticity lateral wall extends to the outside of lower shield cover.

Further, the ends of both the elastic side walls are simultaneously bent inward or simultaneously bent outward with respect to the connecting plate.

Further, the lower shield cover is provided with at least two through grooves;

lower shield cover include with lead to the groove one-to-one elastic connecting piece, elastic connecting piece includes cross linking arm and two protruding portions, the cross linking arm has two long lateral walls and two short lateral walls, long lateral wall with form the space between the lateral wall that leads to the groove, two short lateral walls of cross linking arm with the both sides fixed connection who leads to the groove, two the protruding portion is fixed respectively the both ends of two long lateral walls of cross linking arm just extend to the outside of shield cover, two the protruding portion is controlled to drive two long lateral walls to lead to the inslot side and buckle.

Furthermore, the elastic connecting piece is a spring, and the spring is fixedly connected with the bottom surface of the lower shielding case.

Further, the lower end of the upper shielding cover extends outwards horizontally along the circumferential direction to form a connecting edge, and the connecting edge is positioned below the side wall of the shell;

the top surface of the lower shielding cover is convexly provided with an annular bulge upwards, the annular bulge extends into the upper shielding cover, and the connecting edge is positioned on the outer side of the annular bulge and is attached to the top surface of the lower shielding cover.

Furthermore, two connecting columns are convexly arranged on the inner side of the top of the upper shielding cover, the two static contacts respectively penetrate through the shell and the corresponding connecting columns, and the first magnetic conduction blocks are fixed between the two connecting columns and distributed above the movable contact bridge along the width of the movable contact bridge.

Furthermore, the upper shielding cover comprises a plurality of arc extinguishing windows, the arc extinguishing windows are respectively arranged around the upper shielding cover, and the arc extinguishing windows are arranged opposite to the moving contact and the static contact.

Further, the relay further comprises a connecting ring, and the lower shielding cover is located on the inner side of the connecting ring;

the upper part of the magnetic pole plate is convexly provided with an annular convex rib, and the shell is connected with the magnetic pole plate through the connecting ring and the convex rib.

Furthermore, two sides of the width of the movable contact bridge are inwards sunken to form gaps;

the second magnetic conduction block is of a U-shaped structure and is located below the movable contact bridge, and the two side walls of the second magnetic conduction block penetrate through the notches on the two sides of the movable contact bridge and extend towards the first magnetic conduction block.

Further, the pushing assembly includes:

the fixed support is positioned below the movable contact bridge;

the stop plate comprises a bearing plate and two fixed side arms, the two fixed side arms are arranged on two sides of the bearing plate along the width direction of the movable contact bridge, the bearing plate is buckled on the top surface of the movable contact bridge, and the two fixed side arms respectively extend to two sides of the fixed support and are fixedly connected with the fixed support;

the first elastic piece is arranged between the two fixed side arms, one end of the first elastic piece is connected with the fixed support, and the other end of the first elastic piece is connected with the movable contact bridge;

the push rod penetrates through the magnetic pole plate and the lower shielding cover and is movably connected with the magnetic pole plate and the lower shielding cover, and the top of the push rod is connected with one surface of the fixed support, which faces back to the first elastic piece.

Furthermore, the bearing plate is provided with two openings, two side walls of the second magnetic conduction block respectively penetrate through the corresponding openings, and end surfaces of two side walls of the second magnetic conduction block are higher than a plane where the bearing plate is located.

Further, the relay further includes:

the sleeve is positioned below the magnetic pole plate and is fixedly connected with the magnetic pole plate;

the static iron core is positioned in the sleeve and the magnetic pole plate and is fixedly connected with the sleeve and the magnetic pole plate;

the movable iron core is movably arranged in the sleeve and is positioned below the static iron core;

the two ends of the second elastic piece are respectively connected with the static iron core and the movable iron core;

the pushing rod penetrates through the static iron core and the second elastic piece and penetrates into the movable iron core, the pushing rod is movably connected with the static iron core, and the pushing rod is fixedly connected with the movable iron core.

The movable short-circuit-resistant direct-current relay of this embodiment makes lower shield cover including the elastic connection spare that has certain stroke through setting up, elastic connection spare absorbs the tolerance when casing and magnetic pole plate welding, the stable contact laminating of shield cover about can guaranteeing, when the relay leads to the heavy current, two magnetic conduction blocks form the magnetic conduction return circuit and produce the elasticity that suction is greater than lower shield cover each other, make two magnetic conduction block open distances diminish, the suction grow, thereby can fine assurance movable contact bridge and two static contacts keep the actuation, the stability and the anti short circuit ability of relay work have been promoted greatly.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent from the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

fig. 1 is a cross-sectional view of a relay according to an embodiment of the present invention;

fig. 2 is another angular cross-sectional view of a relay according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of the pushing assembly and the movable contact bridge according to the embodiment of the present invention;

fig. 4 is a schematic structural diagram of a part of the pushing assembly and the movable contact bridge according to the embodiment of the present invention;

fig. 5 is a schematic structural diagram of the movable contact bridge and the second magnetic conductive block according to the embodiment of the present invention;

fig. 6 is a schematic structural view of a second magnetic conduction block according to an embodiment of the present invention;

FIG. 7 is a schematic structural view of a stopper plate according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a lower shield according to an embodiment of the present invention;

fig. 9 is a schematic view of another angle of the lower shield according to the embodiment of the present invention;

fig. 10 is another schematic structural view of the lower shield according to the embodiment of the present invention;

fig. 11 is another schematic structural diagram of the lower shield according to the embodiment of the present invention;

fig. 12 is a further schematic structural view of the lower shield according to the embodiment of the present invention;

fig. 13 is a schematic structural view of a portion of a lower shield according to an embodiment of the present invention;

fig. 14 is a schematic structural view of an elastic connection member according to an embodiment of the present invention;

fig. 15 is another schematic structural view of the elastic connecting member according to the embodiment of the present invention;

fig. 16 is a schematic structural view of a magnetic pole plate according to an embodiment of the present invention;

fig. 17 is a schematic structural diagram of a movable contact bridge according to an embodiment of the present invention;

fig. 18 is a schematic structural diagram of an upper shield according to an embodiment of the present invention.

Detailed Description

The present invention will be described below based on examples, but the present invention is not limited to only these examples. In the following detailed description of the present invention, certain specific details are set forth in detail. It will be apparent to those skilled in the art that the present invention may be practiced without these specific details. Well-known methods, procedures, components and circuits have not been described in detail so as not to obscure the present invention.

Further, those of ordinary skill in the art will appreciate that the drawings provided herein are for illustrative purposes and are not necessarily drawn to scale.

Meanwhile, it should be understood that, in the following description, a "circuit" refers to a conductive loop constituted by at least one element or sub-circuit through electrical or electromagnetic connection. When an element or circuit is referred to as being "connected to" another element or element/circuit is referred to as being "connected between" two nodes, it may be directly coupled or connected to the other element or intervening elements may be present, and the connection between the elements may be physical, logical, or a combination thereof. In contrast, when an element is referred to as being "directly coupled" or "directly connected" to another element, it is intended that there are no intervening elements present.

Unless the context clearly requires otherwise, throughout the description, the words "comprise", "comprising", and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is, what is meant is "including, but not limited to".

In the description of the present invention, it is to be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In addition, in the description of the present invention, "a plurality" means two or more unless otherwise specified.

Fig. 1 to fig. 2 are schematic structural diagrams of the relay according to the present embodiment. As shown in fig. 1 and 2, the movable short-circuit-resistant dc relay includes a housing 1, a magnetic pole plate 2, an upper shield 3, a first magnetic conductive block 4, two fixed contacts 5, a lower shield 6, a movable contact bridge 7, a pushing assembly 8, and a second magnetic conductive block 9. Wherein, the housing 1 and the magnetic pole plate 2 surround to form a containing cavity. The upper shield cover 3, the first magnetic conduction block 4, the two fixed contacts 5, the lower shield cover 6, the movable contact bridge 7 and the second magnetic conduction block 9 are arranged in a containing cavity formed by the enclosure 1 and the magnetic pole plate 2.

Specifically, the housing 1 has an accommodating space with a downward opening, and the magnetic pole plate 2 closes the opening of the accommodating space to form a closed accommodating cavity. The shape of the shell 1 and the accommodating space in the shell can be of a columnar structure with a rectangular, circular, oval or polygonal cross section, and the shape can be set according to actual product requirements. The shell 1 can be made of high-temperature-resistant and insulating materials such as ceramics, electric arcs generated by the relay can be extinguished more conveniently, and the service life and the use safety factor of the relay are improved.

The relay further comprises a connecting ring 10, as shown in fig. 1 and 2. The coupling ring 10 includes a vertical portion integrally formed with the bottom of the housing 1 and an edge portion extending outward of the housing 1 along the vertical portion. The vertical part is an annular structure with the same shape as the housing 1 and the accommodating space. The shell 1 is fixedly connected with the magnetic pole plate 2 through the connecting ring 10, and the air tightness of the relay can be guaranteed. A certain distance exists between the vertical part of the connecting ring 10 and the inner wall of the accommodating space, so that the positions of the upper shielding case 3 and the lower shielding case 6 in the accommodating cavity are limited. The connection ring 10 may be formed of kovar (also called iron-nickel-cobalt alloy), SPCC (cold rolled carbon steel sheet and steel strip), copper and copper alloy, or stainless steel, and the like, and is used for welding with the magnetic pole plate 2. In the present embodiment, the housing 1 and the coupling ring 10 are integrally formed by an injection molding process, an insert molding process, or the like.

The magnetic pole plate 2 is arranged below the connecting ring 10 and welded with the edge part of the connecting ring 10 to form a containing cavity. Specifically, an annular rib 21 is protruded above the magnetic pole plate 2, as shown in fig. 16. The annular rib 21 is located at a position on the magnetic pole plate 2 facing the middle of the edge of the connecting ring 10. When the magnetic pole plate 2 is connected to the connection ring 10, the annular rib 21 is melted to fixedly connect the two.

The upper shield 3 is disposed in the receiving cavity, as shown in fig. 1 and 2. The upper shield 3 has a receiving cavity with a downward opening, and the lower end of the upper shield 3 is formed with a connecting edge 31 extending horizontally outward in the circumferential direction, as shown in fig. 18. The outer annular dimension of the connecting edge 31 is larger than the dimension of the accommodating cavity and smaller than the annular dimension of the vertical part of the connecting ring 10, so that the connecting edge 31 is located below the bottom of the housing 1 and limited by the bottom of the housing 1.

The two static contacts 5 respectively penetrate through the housing 1 and the upper shielding case 3 in sequence, and the outer sides of the static contacts 5 are fixed and hermetically connected with the housing 1, as shown in fig. 1 and 2. Preferably, the two stationary contacts 5 are symmetrically arranged on the housing 1 and the upper shield 3.

Specifically, the top of the housing 1 has two symmetrical first through holes, the top of the upper shielding case 3 has two second through holes respectively communicated with the first through holes, and the two stationary contacts 5 respectively sequentially penetrate through the first through holes and the second through holes to enter the accommodating cavity of the upper shielding case 3. Furthermore, two connecting posts 32 are convexly arranged on the inner side of the top of the upper shielding case 3, and two second through holes penetrate through the connecting posts 32. The connecting column 32 is used for increasing the creepage distance between the two static contacts 5, and meanwhile, ash generated after the static contacts 5 are evaporated can be well prevented from falling on the inner surface of the shell 1, so that the voltage resistance and the insulating property of a relay product are improved. Preferably, a cylinder is convexly arranged on the outer side of the top of the housing 1, cylinders are convexly arranged on the inner side and the outer side of the top of the upper shielding case 3, the first through hole penetrates through the cylinder on the housing 1, and the second through hole penetrates through the cylinder on the upper shielding case 3, so that the function is the same as that of the first through hole.

The lower shield 6 is located between the upper shield 3 and the magnetic pole plate 2 and inside the connecting ring 10, that is, the lower shield 6 is located in the receiving cavity, as shown in fig. 1 and 2. The movable contact bridge 7, the pushing assembly 8 and the second magnetic conduction block 9 are all located between the upper shielding case 3 and the lower shielding case 6 and are all located below the two static contacts 5.

Specifically, the moving contact bridge 7 is disposed on the top of the pushing assembly 8, and two moving contacts at two ends of the moving contact bridge 7 correspond to the two fixed contacts 5, as shown in fig. 1 to 4. The pushing assembly 8 is used for pushing the movable contact bridge 7 to move so that the two movable contacts are connected with or disconnected from the two fixed contacts 5. In the present embodiment, the upper shield case 3 includes a plurality of arc extinguishing windows 33, as shown in fig. 18. The plurality of arc extinguishing windows 33 are respectively arranged on the periphery of the upper shielding case 3 and are opposite to the moving contact and the static contact of the moving contact bridge 7. The arc extinguishing window 33 can make the arc generated by the disconnection of the moving contact and the fixed contact elongate on the surface of the shell 1 and the surface of the upper shielding case 3, which is more beneficial to extinguishing the arc.

The second magnetic conduction block 9 is fixedly connected with the movable contact bridge 7, and the second magnetic conduction block 9 is located between two movable contacts of the movable contact bridge 7, as shown in fig. 3 and 4. The first magnetic conductive block 4 is fixedly arranged at the top of the inner side of the upper shielding case 3, and the first magnetic conductive block 4 is fixed between the two connecting posts 32 (i.e. between the two fixed contacts 5) and arranged opposite to the second magnetic conductive block 9. After the pushing assembly 8 pushes the movable contact to be communicated with the fixed contacts 5, the second magnetic conduction block 9 is close to the first magnetic conduction block 4, at the moment, an external circuit is conducted, the movable contact bridge 7 can generate an annular magnetic field around the movable contact bridge 7 through a large current, the annular magnetic field forms a closed magnetic conduction loop through the first magnetic conduction block 4 and the second magnetic conduction block 9, a mutual attraction force is generated between the first magnetic conduction block 4 and the second magnetic conduction block 9, the second magnetic conduction block 9 drives the movable contact bridge 7 to be attracted upwards, and therefore the two movable contacts of the movable contact bridge 7 are in more stable contact with the two fixed contacts 5, and the working stability and the short-circuit resistance of the relay are greatly improved. The first magnetic conduction block 4 and the second magnetic conduction block 9 can be made of iron, cobalt, nickel, alloys thereof and other materials.

Further, in order to adjust the distance between the first magnetic conduction block 4 and the second magnetic conduction block 9, so that the distance between the first magnetic conduction block 4 and the second magnetic conduction block 9 can meet the working requirement, a protrusion can be selectively and convexly arranged between the two connecting posts 32 on the upper shielding cover 3, and the first magnetic conduction block 4 can be arranged on the protrusion. The working requirement means that when the moving contact is abutted with the static contact, the first magnetic conduction block 4 and the second magnetic conduction block 9 can be infinitely close to or abutted with each other, and a magnetic conduction loop is formed when a large current is conducted; when the moving contact and the static contact are separated, the first magnetic conduction block 4 and the second magnetic conduction block 9 are separated. The fixing mode between the first magnetic conduction block 4 and the upper shielding case 3 can be injection molding, gluing, buckling, hot melting, riveting and the like.

In the present embodiment, the movable contact bridge 7 has a strip-shaped plate-like structure, as shown in fig. 5 and 17. Two ends of the movable contact bridge 7 are respectively arranged towards the two static contacts 5. Two sides of the width of the movable contact bridge 7 are recessed inwards to form two gaps 71, and the width is perpendicular to the two movable contact connecting lines, as shown in fig. 17. The second magnetic conduction block 9 is of a U-shaped structure, as shown in fig. 6. The second magnetic conduction block 9 is located below the movable contact bridge 7, and two side walls of the second magnetic conduction block 9 respectively penetrate through the notches 71 on two sides of the movable contact bridge 7 and extend towards the first magnetic conduction block 4, as shown in fig. 5. Two side walls of the second magnetic conduction block 9 extend to the top part higher than the movable contact bridge 7 and are arranged opposite to the first magnetic conduction block 4.

Further, the bottom of the second magnetic conduction block 9 extends to the two moving contacts of the moving contact bridge 7 along the length direction, and two extending sides are respectively provided with a fixing hole. And two fixed columns are convexly arranged on the bottom surface of the movable contact bridge 7. The movable contact bridge 7 and the second magnetic conduction block 9 are inserted into the fixing hole through the fixing column to be fixedly connected. In other modes, the bottom surface of the movable contact bridge 7 is provided with two fixing holes with downward openings, and the bottom of the second magnetic conduction block 9 is provided with two fixing columns which are fixedly connected with the two fixing holes of the movable contact bridge 7 in an upward protruding mode. In addition, the movable contact bridge 7 and the second magnetic conduction block 9 can be fixedly connected through a fastener, welded, fixed and the like.

In a preferred embodiment, the gap 71 is located in the middle of two moving contacts of the moving contact bridge 7, so that the second magnetic conductive block 9 is fixed in the middle of the moving contact bridge 7. Correspondingly, the first magnetic conduction block 4 is arranged right above the second magnetic conduction block 9. Above-mentioned mode of setting up can make the suction that second magnetic conduction piece 9 produced can drive the both sides of moving contact bridge 7 rebound simultaneously, avoids taking place the slope, simultaneously can also the size of furthest reduction relay, adapts to different space demands.

The pushing assembly 8 is located below the movable contact bridge 7 and connected with the movable contact bridge 7 and used for pushing the movable contact bridge 7 to move up and down. Specifically, the pushing assembly 8 includes a fixed bracket 81, a stopper plate 82, a first elastic member 83, and a pushing rod 84, as shown in fig. 1 to 3. The fixed bracket 81 is located between the movable contact bridge 7 and the lower shield 6. The pushing rod 84 is located below the fixing bracket 81, one end of the pushing rod 84 is fixedly connected with the fixing bracket 81, and the other end of the pushing rod 84 penetrates through the lower shielding case 6 and the magnetic pole plate 2, as shown in fig. 1 and 2. The pushing rod 84 is movably connected with the magnetic pole plate 2 and the lower shielding case 6 and used for pushing the fixing support 81 to move up and down.

In this embodiment, the second magnetic block 9 has an exit hole at the middle of the bottom. The first elastic member 83 is located above the fixed bracket 81, and has one end fixedly connected to the fixed bracket 81 and the other end fixedly connected to the bottom of the movable contact bridge 7 through the through hole, as shown in fig. 1 and 2. In other embodiments, the bottom of the second magnetic conductive block 9 may not be provided with a through hole, and one end of the first elastic member 83 is fixedly connected to the fixing bracket 81, and the other end is fixedly connected to the bottom of the second magnetic conductive block 9.

The stop plate 82 includes a receiving plate 821 and two fixed side arms 822, as shown in FIG. 7. The two fixed side arms 822 are disposed on two sides of the receiving plate 821 in the width direction of the movable contact bridge 7. The receiving plate 821 is opened at both sides in the width direction by the opening 85. The receiving plate 821 is fastened on the top surface of the movable contact bridge 7, and two side walls of the second magnetic conduction block 9 respectively penetrate through the two openings 85 and extend upward, as shown in fig. 3. The two fixing side arms 822 are located at the outer sides of the two side walls of the second magnetic conduction block 9, respectively extend to the two sides of the fixing bracket 81 and the first elastic element 83, and are fixedly connected with the fixing bracket 81, as shown in fig. 3. Preferably, the two sides of the fixing bracket 81 are respectively provided with a connecting piece, and the two fixing side arms 822 are respectively fixedly connected with the two connecting pieces. The two fixing side arms 822 limit the first elastic member 83 to prevent the first elastic member 83 from inclining outward, so as to facilitate assembly.

In one embodiment, the two fixed side arms 822 and the receiving plate 821 are integrally formed. In this way, the connection between the two fixed side arms 822 and the receiving plate 821 is firm, and the impact resistance of the stopper plate 82 is improved. The first elastic member 83 is for providing an elastic force. When the two ends of the moving contact bridge 7 contact with the two fixed contacts 5, the elastic force of the first elastic member 83 acts on the moving contact bridge 7 to maintain the abutting relationship between the moving contact bridge 7 and the fixed contacts 5.

When the push rod 84 pushes the fixed bracket 81, the stop plate 82, the first elastic element 83, the movable contact bridge 7 and the second magnetic conduction block 9 to move upward toward the fixed contact 5, the two movable contacts at the two ends of the movable contact bridge 7 are respectively abutted against the two fixed contacts 5. At this time, the second magnetic conduction block 9 abuts against or is fixed in relative position with the first magnetic conduction block 4. With the over travel (over travel operation), the push rod 84 continues to push the fixed support 81 to move upwards to compress the first elastic element 83 due to the fixed position of the movable contact bridge 7 at the moment, so that the requirement of the relay operation during the over travel operation is met.

Because the first magnetic conduction block 4 is arranged on the inner side surface of the top of the upper shielding case 3, the position relation between the first magnetic conduction block 4 and the second magnetic conduction block 9 cannot be changed due to the continuous process of overtravel. That is to say, the magnetic air gap between the first magnetic conduction block 4 and the second magnetic conduction block 9 cannot be changed, the magnetic air gap between the first magnetic conduction block 4 and the second magnetic conduction block 9 cannot be enlarged along with the enlargement of the overtravel, the magnetic attraction between the first magnetic conduction block 4 and the second magnetic conduction block 9 cannot be influenced by the enlargement of the overtravel, the short-circuit resistance function of the relay is not influenced, and therefore the contradiction between the overtravel and the magnetic air gap is solved.

In the field of relay technology, over travel is a very important parameter. When the moving contact bridge 7 contacts with the two stationary contacts 5, the push rod 84 does not stop moving immediately, the fixed bracket 81 continues to move, and the first elastic member 83 is further compressed. When the moving contact bridge 7 is in contact with the two fixed contacts 5, the two fixed contacts 5 limit the continuous movement of the moving contact bridge 7, at this time, the moving contact bridge 7 and the second magnetic conduction block 9 will not move, the fixed bracket 81, the stop plate 82 and the push rod 84 continue to move, and after the first elastic piece 83 continues to be compressed to a certain degree, the fixed bracket 81, the stop plate 82 and the push rod 84 stop moving.

In this embodiment, end surfaces of two side walls of the second magnetic conductive block 9 are higher than a top surface of the receiving plate 821. When the overtravel proceeds, the push rod 84 firstly continues to push the fixed bracket 81 and the stop plate 82 to move upwards, and when the receiving plate 821 of the stop plate 82 abuts against the first magnetic conduction block 4, the fixed bracket 81 starts to press the first elastic member 83 so that the first elastic member 83 is compressed, thereby meeting the requirement of the relay operation during the overtravel operation. Specifically, when the movable contact bridge 7 is just in contact with the two fixed contacts 5, the distance between the top of the first magnetic conductive block 4 and the receiving plate 821 is the maximum amplitude of the over travel in this embodiment. When the relay is closed and in a stable state, there is a gap between the receiving plate 821 and the top end portion of the first magnetic conduction block 4 to avoid the collision between the receiving plate 821 and the first magnetic conduction block 4.

The stop plate 82 is arranged to improve the stability of the upward movement of the movable contact bridge 7 and the second magnetic conduction block 9 during non-over travel. Meanwhile, the stop plate 82 and the first elastic element 83 are arranged to provide a certain over travel displacement amount during over travel. The first elastic member 83 may be made of elastic material or form such as spring, rubber, silicon rubber, memory alloy, etc. The stop plate 82 is made of a non-magnetic material or a weak magnetic material, so that the situation that the stop plate 82 cannot move continuously or is blocked due to the influence of the over-travel motion of the stop plate under the action of attraction is avoided.

In this embodiment, the fixing bracket 81 has a cylindrical structure. The fixed support 81 comprises a first cylindrical portion and a second cylindrical portion which are coaxially arranged, and the first cylindrical portion is located above the second cylindrical portion and close to the movable contact bridge 7. A groove is formed at the top of the first cylindrical portion, and one end of the first elastic member 83 is fixedly disposed in the groove. And a through hole is formed in the middle of the lower shielding case 6. The through hole is larger than the radial dimension of the second cylindrical portion and smaller than the radial dimension of the first cylindrical portion, so that the first cylindrical portion of the fixing bracket 81 can move in the height direction of the lower shield shell 6. The two connecting pieces are arranged on the radial outer side surface of the second cylindrical part. The push rod 84 is fixedly connected to the bottom of the first cylindrical portion.

In other embodiments, the bottom dimension of the fixed bracket 81 is larger than the dimension of the through hole of the lower shield 6, so that the fixed bracket 81 moves between the movable contact bridge 7 and the lower shield 6. The push rod 84 passes through the through hole and the magnetic pole plate 2 and is movably connected with the lower shielding case 6 and the magnetic pole plate 2 respectively.

Specifically, the magnetic pole plate 2 is further provided with a moving through hole. The moving through hole is located right below the fixed bracket 81 and is used for the push rod 84 to penetrate out and move. The push rod 84 is a stressed component, the push rod 84 is a cylindrical structure, and the push rod 84 pushes the fixed bracket 81 to move under the action of electromagnetic force, so that the movable contact bridge 7 moves towards the fixed contact 5.

The relay further includes a sleeve 11, a stationary core 12, a movable core 13, and a second elastic member 14, as shown in fig. 1 and 2. The sleeve 11 is located below the magnetic pole plate 2, and the connecting edge at the opening of the sleeve 11 is fixedly connected with the magnetic pole plate 2 outside the movable through hole and used for sealing the magnetic pole plate 2. The static iron core 12 is located in the sleeve 11 and the movable through hole of the magnetic pole plate 2, and the static iron core 12 is fixedly connected with the sleeve 11 and the magnetic pole plate 2. The movable iron core 13 is arranged in the sleeve 11 and positioned below the static iron core 12, and the movable iron core 13 moves between the bottom of the sleeve 11 and the static iron core 12. The second elastic element 14 is arranged in the sleeve 11, and two ends of the second elastic element 14 are respectively fixedly connected with the static iron core 12 and the movable iron core 13.

The pushing rod 84 penetrates out of the lower shielding case 6 and enters the stationary core 12, and penetrates through the stationary core 12 and the second elastic member 14 and is inserted into the movable core 13. The pushing rod 84 is movably connected with the stationary iron core 12, and the pushing rod 84 is fixedly connected with the movable iron core 13.

When the relay is used, a coil is sleeved outside the sleeve 11. The coil is energized to generate a magnetic field, the magnetic field forms a magnetic circuit through the static iron core 12 and the movable iron core 13, and the static iron core and the movable iron core generate mutually attracted electromagnetic force. Because the static iron core 12 is fixed on the sleeve 11 and the magnetic pole plate 2, the moving iron core 13 drives the pushing rod 84 to move upwards under the action of electromagnetic force, and further drives the moving contact bridge 7 and the second magnetic conduction block 9 to move upwards, so that the two moving contacts of the moving contact bridge 7 are respectively connected with the two static contacts 5 in an attraction manner. During the upward movement of the plunger 13, the plunger 13 presses the second elastic member 14, so that the second elastic member 14 is compressed. When the coil is powered off, the movable iron core 13 drives the pushing rod 84 to move downward under the action of the elastic force of the second elastic member 14, and further drives the movable contact bridge 7 and the second magnetic conductive block 9 to move downward, so that the movable contact bridge 7 is separated from the two fixed contacts 5.

The second elastic member 14 is a spring, but may have other elastic structures. The sleeve 11 may be made of stainless steel or the like.

In a preferred embodiment, a washer is further disposed between the top of the stationary core 12 and the bottom of the fixed bracket 81 for buffering noise generated by the pushing rod 84 during the movement of pushing the fixed bracket 81. Wherein, the gasket can comprise two gaskets, one stainless steel gasket and one silicon rubber gasket.

The two static contacts 5 are used for connecting an external circuit. When a coil in the relay is electrified and the two fixed contacts 5 and the movable contact bridge 7 are attracted and communicated, an external circuit is conducted, and current generates an annular magnetic field around the movable contact bridge 7 through the movable contact bridge 7. The first magnetic conduction block 4 and the second magnetic conduction block 9 are arranged in the magnetic field of the movable contact bridge 7, the first magnetic conduction block 4 and the second magnetic conduction block 9 generate a magnetic conduction loop, so that mutual attraction is generated between the first magnetic conduction block and the second magnetic conduction block, the second magnetic conduction block 9 drives the movable contact bridge 7 to be subjected to upward electromagnetic attraction, and the movable contact bridge 7 is contacted with the two fixed contacts 5 more stably. The larger the current is, the larger the magnetic field is, the larger the attraction force between the two is, the electric repulsion force formed by the contact and flow guiding of the movable contact bridge 7 and the two static contacts 5 can be counteracted, thus under the condition of passing large current (such as 6000A-10000A), the movable contact bridge 7 and the two static contacts 5 can be well ensured to be attracted, and the working stability and the short circuit resistance of the relay are greatly improved.

The lower shield 6 is located between the upper shield 3 and the pole plate 2 as shown in figures 1 and 2. The lower shield 6 is used for supporting and positioning the upper shield 3 and preventing electric arcs generated by separating the moving contact and the fixed contact from running onto the magnetic pole plate 2.

In the present embodiment, the lower shield 6 includes an elastic connector 61 extending to the outside of the bottom surface of the lower shield 6, as shown in fig. 9, 11 and 12. The elastic connection member 61 is in contact with the top surface of the magnetic pole plate 2 so that a gap is formed between the bottom surface of the lower shield 6 and the magnetic pole plate 2. Whereby said elastic connection 61 gives the lower shield 6 a certain elastic travel. When the relay is in a non-working state, the elastic connecting piece 61 can absorb tolerance formed before and after the casing 1 and the magnetic pole piece 2 are welded and fixed, the connecting edge 31 of the upper shielding cover 3 is in contact fit with the bottom of the casing 1 and the lower shielding cover 6 according to the elasticity of the elastic connecting piece 61, and therefore the first magnetic conduction block 4 fixed at the top of the inner side of the upper shielding cover 3 is located at the highest position, and the distance between the first magnetic conduction block 4 and the second magnetic conduction block 9 is guaranteed to be the largest.

Furthermore, the elastic force value of the elastic connecting piece 61 can ensure that the upper shield cover 3 and the lower shield cover 6 do not move up and down in the accommodating cavity due to vibration impact and the like. When the movable contact bridge 7 and the two fixed contacts 5 of the relay are abutted against the small current (such as 200A-2500A), the suction force generated between the first magnetic conduction block 4 and the second magnetic conduction block 9 is smaller than the elastic force of the lower shielding case 6, and at the moment, the relative position between the upper shielding case 3 and the lower shielding case 6 is unchanged, so that a larger distance between the first magnetic conduction block 4 and the second magnetic conduction block 9 is ensured.

When a large current (such as 6000A-10000A) is connected between the moving contact bridge 7 and the two fixed contacts 5 of the relay in an abutting mode, the suction force generated between the first magnetic conduction block 4 and the second magnetic conduction block 9 is larger than the elastic force of the lower shielding cover 6, the first magnetic conduction block 4 drives the upper shielding cover 3 to move downwards, the elastic connecting piece 61 of the lower shielding cover 6 is stressed to compress downwards so that the lower shielding cover 6 moves downwards at the same time, the distance between the first magnetic conduction block 4 and the second magnetic conduction block 9 is reduced due to the downward movement of the first magnetic conduction block 4, the suction force between the first magnetic conduction block 4 and the second magnetic conduction block 9 is increased, the moving contact bridge 7 can be well ensured to be attracted with the two fixed contacts 5, and the working stability and the short circuit resistance of the relay are greatly improved.

That is, the elastic force of the elastic connecting member 61 of the lower shield 6 is used to control the up-and-down movement of the upper shield 3, so as to control the distance between the first magnetic conductive block 4 and the second magnetic conductive block 9, the distance between the first magnetic conductive block 4 and the second magnetic conductive block 9 determines the size of the suction force between the first magnetic conductive block 4 and the second magnetic conductive block 9, the smaller the distance between the first magnetic conductive block 4 and the second magnetic conductive block 9 is, the larger the suction force therebetween is, and the smaller the suction force therebetween is.

In a preferred embodiment, the top surface of the lower shield 6 is provided with an annular protrusion 64 protruding upward, as shown in fig. 8 and 10. Annular protrusion 64 stretches into go up the intracavity that holds of shield cover 3, connection edge 31 is located the annular protrusion 64 outside and with the top surface laminating of shield cover 6 down avoids last shield cover 3 and the relative horizontal direction of shield cover 6 to remove down.

In one embodiment, the bottom surface of the lower shield 6 is recessed upwardly to form two grooves 62, as shown in fig. 13. Two grooves 62 are symmetrically provided on the bottom surface of the lower shield 6. The lower shield 6 includes two elastic connectors 61, each of which is fixed in a corresponding recess 62, as shown in fig. 11 and 12. Wherein, two elastic connecting pieces 61 extend out of the two grooves 62 by the elastic stroke of the elastic connecting pieces 61. The number of the grooves 62 and the number of the elastic connecting pieces 61 can be set arbitrarily according to requirements, and the arrangement position is avoided by the middle penetrating hole.

The elastic connection member 61 includes a connection plate 611 and two elastic sidewalls 612 disposed at both sides of the connection plate 611, as shown in fig. 11, 12, 14 and 15. The connecting plate 611 is detachably connected to the bottom of the groove 62, and the two elastic side walls 612 extend to the outside of the lower shield 6. The lower shield 6 changes the distance from the lower shield 6 to the magnetic pole plate 2 by elastic deformation of the two elastic sidewalls 612, thereby changing the distance from the first magnetic conductive block 4 to the second magnetic conductive block 9. The detachable manner includes a fastener connection or a snap connection, etc. The groove 62 may allow for detachably attached fasteners, snaps, etc. to be located within the groove 62, thereby increasing the spring travel of the lower shield 6. Preferably, the ends of the two elastic sidewalls 612 respectively extend in a direction away from each other to form a V-shape or in a direction close to each other, that is, the two elastic sidewalls are simultaneously bent inward or simultaneously bent outward relative to the connecting plate, as shown in fig. 14 and 15.

In addition, the bottom surface of the lower shield 6 may not be provided with the groove 62. The connection plate 611 of the elastic connection member 61 is directly fixedly connected to the bottom surface of the lower shield 6. In addition, the elastic connecting piece 61 can also adopt a plastic wedge-shaped, L-shaped, i-shaped and other plane structure which is higher than the lower end surface of the lower shielding case 6, so that the lower shielding case 6 has elasticity with a certain stroke, and the elastic connecting piece 61 can also be fixedly connected with the lower shielding case 6 in a metal spring, elastic sheet and other modes.

In one embodiment, the lower shield 6 has two through slots 63 and elastic connectors 61 corresponding to the through slots 63 one by one, as shown in fig. 8 and 9. Wherein the elastic connecting member 61 comprises a cross-shaped connecting arm 613 and two protrusions 614, as shown in fig. 9. Two opposite short side walls of the cross-shaped connecting arm 613 are fixedly connected with two sides of the through groove 63, and a gap is formed between the two opposite long side walls and the side walls of the through groove 63. The two protruding portions 614 are fixed to the outer sides of the two opposite long side walls of the cross-shaped connecting arm 613 and extend to the outer side of the lower shield 6. The two opposite long sidewalls of the cross-shaped connecting arm 613 are deformed to move the two ends of the two long sidewalls into the through groove 63, so as to change the distance from the lower shield 6 to the magnetic pole plate 2, thereby changing the distance from the first magnetic conductive block 4 to the second magnetic conductive block 9. The height of the projection 614 is a travel distance by which the lower shield 6 can move. The lower shield 6 and the elastic connection member 61 are integrally formed.

The relay is in the equipment in-process, to the acceping of relay in the chamber be sealed in can carry out refrigerated gas to electric arc, strengthened the arc extinguishing performance of the anti short circuit structure of relay. The gas may be a mixed gas mainly containing hydrogen.

The top of the promotion subassembly of this embodiment relay is connected with the movable contact bridge and is used for promoting movable contact bridge and two static contacts intercommunication or disconnection, the lower shield of this relay is including making it have the elastic connection spare of certain stroke, elastic connection spare absorbs the tolerance when casing and magnetic pole plate welding, can guarantee the stable contact laminating of shield from top to bottom, when the relay leads to the heavy current, two magnetic conduction blocks form the magnetic conduction return circuit and produce the elasticity that suction is greater than shield down each other, make two magnetic conduction block open distance diminish, the suction grow, thereby can fine assurance movable contact bridge and two static contacts keep the actuation, the stability and the anti short circuit ability of relay work have been promoted greatly.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims (14)

1. A movable short-circuit resistant dc relay, the relay comprising:

the magnetic pole plate comprises a shell (1) and a magnetic pole plate (2), wherein the shell and the magnetic pole plate surround to form a containing cavity;

the upper shielding cover (3) is arranged in the accommodating cavity;

the first magnetic conduction block (4) is fixedly arranged at the top of the inner side of the upper shielding case (3);

the two static contacts (5) are fixedly connected with the shell (1) and penetrate through the shell (1) and the upper shielding case (3);

a lower shield (6) located between the upper shield (3) and the pole plate (2);

the movable contact bridge (7) is positioned below the two static contacts (5) and between the lower shielding case (6), and the two movable contacts of the movable contact bridge (7) correspond to the two static contacts (5);

the top of the pushing component (8) is connected with the movable contact bridge (7) to push the two movable contacts of the movable contact bridge (7) to be connected with or disconnected from the two fixed contacts (5);

the second magnetic conduction block (9) is fixedly connected with the movable contact bridge (7) and is arranged opposite to the first magnetic conduction block (4), and after the movable contact is communicated with the static contact (5), the first magnetic conduction block (4) and the second magnetic conduction block (9) form a magnetic conduction loop so that the second magnetic conduction block (9) drives the movable contact bridge (7) to move upwards;

wherein, shield cover (6) are including extending to elastic connection spare (61) in lower shield cover (6) bottom surface outside, elastic connection spare (61) make through elastic deformation go up shield cover (3) drive first magnetic conduction piece (4) remove in order to adjust first magnetic conduction piece (4) with interval between second magnetic conduction piece (9).

2. The relay according to claim 1, characterized in that the push assembly (8) partially protrudes from the lower shield (6) and the pole plate (2), and the push assembly (8) has a coil on its outside, the coil being configured such that when not energized, the upper shield (3) abuts against the bottom of the housing (1) and the lower shield (6) according to the elastic force of the elastic connection (61).

3. The relay according to claim 1, characterized in that the bottom surface of the lower shield (6) is recessed upwards to form at least two grooves (62);

the lower shielding case (6) comprises elastic connecting pieces (61) which correspond to the grooves (62) one by one, each elastic connecting piece (61) comprises a connecting plate (611) and two elastic side walls (612) arranged on two sides of the connecting plate (611), the connecting plate (611) is detachably connected with the bottom of each groove (62), and the two elastic side walls (612) extend to the outer side of the lower shielding case (6).

4. The relay according to claim 3, characterized in that both of the resilient side walls (612) are bent simultaneously inwards or simultaneously outwards with respect to the connection plate (611).

5. The relay according to claim 1, characterized in that the lower shield (6) has at least two through slots (63);

lower shield cover (6) include with lead to groove (63) one-to-one elastic connecting piece (61), elastic connecting piece (61) include cross connecting arm (613) and two protruding portions (614), cross connecting arm (613) have two long side walls and two short side walls, long side wall with form the space between the lateral wall that leads to groove (63), two short side walls of cross connecting arm (613) with the both sides fixed connection who leads to groove (63), two protruding portion (614) are fixed respectively the both ends of two long side walls of cross connecting arm (613) just extend to the outside of shield cover (6) down, two protruding portion (614) are controlled to drive two long side walls to lead to groove (63) inboard bending.

6. The relay according to claim 1, characterized in that the resilient connection (61) is a spring which is fixedly connected to the bottom surface of the lower shield (6).

7. The relay according to claim 1, characterized in that the lower end of the upper shield (3) is formed with a connecting edge (31) extending horizontally outwards in the circumferential direction, the connecting edge (31) being located below the side wall of the housing (1);

the top surface of the lower shielding cover (6) is provided with an annular bulge (64) in an upward protruding manner, the annular bulge (64) extends into the upper shielding cover (3), and the connecting edge (31) is positioned on the outer side of the annular bulge (64) and is attached to the top surface of the lower shielding cover (6).

8. The relay according to any one of claims 1 to 7, wherein two connecting posts (32) are convexly provided on the inner side of the top of the upper shield (3), the two stationary contacts (5) respectively penetrate through the housing (1) and the corresponding connecting posts (32), and the first magnetic conductive block (4) is fixed between the two connecting posts (32) and is distributed above the movable contact bridge (7) along the width of the movable contact bridge (7).

9. The relay according to claim 8, wherein the upper shield (3) comprises a plurality of arc-extinguishing windows (33), the plurality of arc-extinguishing windows (33) are respectively arranged around the upper shield (3), and the arc-extinguishing windows (33) are arranged opposite to the moving contact and the fixed contact.

10. The relay according to claim 1, characterized in that the relay further comprises a connection ring (10), the lower shield (6) being located inside the connection ring (10);

the upper part of the magnetic pole plate (2) is convexly provided with an annular convex rib (21), and the shell (1) is connected with the magnetic pole plate (2) through the connecting ring (10) and the convex rib (21).

11. The relay according to claim 1, characterized in that the width of the movable contact bridge (7) is recessed inwards on both sides to form notches (71);

second magnetic conduction piece (9) are U type structure, second magnetic conduction piece (9) are located the below of movablely touching bridge (7), the both sides wall of second magnetic conduction piece (9) passes breach (71) and the orientation of movablely touching bridge (7) both sides first magnetic conduction piece (4) extend.

12. The relay according to claim 11, characterized in that the push assembly (8) comprises:

the fixed support (81) is positioned below the movable contact bridge (7);

the stop plate (82) comprises a bearing plate (821) and two fixing side arms (822), the two fixing side arms (822) are arranged on two sides of the bearing plate (821) along the width direction of the movable contact bridge (7), the bearing plate (821) is buckled on the top surface of the movable contact bridge (7), and the two fixing side arms (822) respectively extend to two sides of the fixing support (81) and are fixedly connected with the fixing support (81);

the first elastic piece (83), the first elastic piece (83) is arranged between the two fixed side arms (822), one end of the first elastic piece (83) is connected with the fixed support (81), and the other end of the first elastic piece (83) is connected with the movable contact bridge (7);

the push rod (84), the push rod (84) run through magnetic pole plate (2) with shield cover (6) down and with magnetic pole plate (2) with shield cover (6) swing joint down, the top of push rod (84) with fixed bolster (81) dorsad the one side of first elastic component (83) is connected.

13. The relay according to claim 12, wherein the receiving plate (821) has two openings (85), and two side walls of the second magnetic conductive block (9) respectively penetrate through the corresponding openings (85), and end surfaces of two side walls of the second magnetic conductive block (9) are higher than a top surface of the receiving plate (821).

14. The relay according to claim 12, further comprising:

the sleeve (11) is positioned below the magnetic pole plate (2) and is fixedly connected with the magnetic pole plate (2);

the static iron core (12) is positioned in the sleeve (11) and the magnetic pole plate (2), and the static iron core (12) is fixedly connected with the sleeve (11) and the magnetic pole plate (2);

the movable iron core (13) is movably arranged in the sleeve (11) and is positioned below the static iron core (12);

the two ends of the second elastic piece (14) are respectively connected with the static iron core (12) and the movable iron core (13);

the pushing rod (84) penetrates through the static iron core (12) and the second elastic piece (14) and penetrates into the movable iron core (13), the pushing rod (84) is movably connected with the static iron core (12), and the pushing rod (84) is fixedly connected with the movable iron core (13).

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