CN216902706U - Pyrotechnic excitation device and switching device with pyrotechnic excitation device - Google Patents

Abstract

The utility model relates to a pyrotechnic excitation device and a switching device with the pyrotechnic excitation device, wherein the pyrotechnic excitation device comprises an exciter, a piston and a bottom shell, the bottom shell is of a hollow structure, the piston is installed in the bottom shell in a matching mode, the exciter ignites gunpowder and pushes the piston to break through the bottom shell through gas, a non-return structure is arranged on the bottom shell, and after the piston breaks through the bottom shell, the non-return structure prevents the piston from impacting and rebounding, so that the energy loss caused by the rebounding of the piston is reduced.

Description

Pyrotechnic excitation device and switching device with pyrotechnic excitation device

Technical Field

The utility model relates to the field of switching appliances, in particular to a switching appliance with a pyrotechnic excitation device.

Background

The relay is widely applied to remote control, remote measurement, communication, automatic control, electromechanical integration and power electronic equipment, and is a core component for controlling the state of a switch in an electric loop. With the continuous development and change of electrical technology, the load requirement of the main loop is higher and higher, and the requirement of short circuit resistance of the relay is also higher and higher. In recent years, manufacturers propose a main loop short-circuit resistance capability of 20KA or even 30KA, and under such a high short-circuit current, a great short-circuit electric repulsion force occurs between contacts of the relay, so that the movable spring is forced to be repelled from the fixed contact. In order to resist the short circuit electric repulsion force to maintain the closed state of the movable spring and the movable contact, the electric repulsion force has to be resisted by increasing the pressure of the contact spring or the closing magnetic attraction force of the movable spring (namely, the magnetic attraction force for driving the movable spring to move and close through an electromagnetic driving mechanism). However, when the pressure of the contact spring or the closing magnetic attraction of the movable spring piece is increased, the normal breaking action of the movable spring piece is also influenced, and when the short-circuit current is further increased, if the short-circuit current is not broken timely, the safety of a loop cannot be guaranteed. Therefore, in some prior art, a pyrotechnic actuator (pyrotechnical activator) is arranged to help the relay to perform rapid breaking, when a system monitors that a short-circuit current reaches a critical value, the system triggers the actuator to ignite gunpowder, and a movable contact (movable contact spring) is pushed to rapidly break by means of the impact force of gunpowder explosion, so that a loop protection effect is realized.

The existing pyrotechnic excitation device generally comprises a piston, and after the pyrotechnic excitation device is ignited, high-pressure gas pushes the piston to actuate, and the piston pushes a movable contact (a movable reed) to be quickly disconnected. However, in the prior art, the pyrotechnic excitation device is not provided with a non-return structure of the piston, and the piston is easy to rebound after impacting the movable reed, so that the kinetic energy of the piston is lost to some extent, and the movable reed is not beneficial to realizing the rapid breaking of the movable reed.

SUMMERY OF THE UTILITY MODEL

Therefore, in order to solve the above problems, the present invention provides a pyrotechnic excitation device with an optimized structure, and based on the pyrotechnic excitation device, a switching apparatus having the pyrotechnic excitation device is also provided.

The utility model is realized by adopting the following technical scheme:

the utility model provides a pyrotechnic excitation device, which comprises an exciter, a piston and a bottom shell, wherein the bottom shell is of a hollow structure, the piston is arranged in the bottom shell in a matching manner, the exciter ignites gunpowder and pushes the piston to break through the bottom shell through gas, a non-return structure is arranged on the bottom shell, and the non-return structure prevents the piston from impacting and rebounding after the piston breaks through the bottom shell.

Preferably, a plurality of staggered cracks are arranged at the bottom of the bottom shell, after the piston breaks through the bottom shell, the bottom of the bottom shell expands outwards from the intersection point of the cracks to form a sharp-tooth-shaped non-return part, and the sharp end of the non-return part abuts against the piston to prevent the piston from rebounding.

Wherein, preferably, the crack is in a shape like a Chinese character ' mi ' or a cross '.

Wherein, preferably, be equipped with radial segment difference structure on the piston.

Preferably, the piston is provided with a neck part with a reduced diameter, and the tip end of the non-return part abuts against a step at one end of the neck part to prevent the piston from rebounding; or the piston is divided into two independent sections and comprises an upper piston and a lower piston, after the lower piston breaks the bottom shell, the upper piston is still remained in the bottom shell, and the tip of the non-return part is propped against the end part of the lower piston to prevent the lower piston from rebounding.

Wherein, preferably, the piston is a structure that gradually contracts in a direction of breaking the bottom case.

The utility model also provides a switching device with the pyrotechnic excitation device, which comprises a switching device body and the pyrotechnic excitation device arranged on the switching device body, wherein the switching device body comprises a fixed static contact part and a movable dynamic contact part to perform a switching function, the pyrotechnic excitation device ignites gunpowder according to the load condition of the switching device body and generates explosion impact force for pushing the movable contact part to be far away from the static contact part so as to assist the switching device to be quickly disconnected, and the pyrotechnic excitation device is the pyrotechnic excitation device.

Preferably, the switch electrical appliance with the pyrotechnic excitation device further includes a restraining member, the restraining member is disposed at a position corresponding to the piston breaking through the bottom case, the restraining member is configured to restrain the movable contact portion from returning towards the stationary contact portion and to be coupled with the movable contact portion, and the restraining member is made of a material which can receive the impact of the piston and does not return to deform.

Preferably, the constraint piece is a constraint frame, and the constraint frame is squashed to be incapable of restoring deformation after receiving the impact of the piston, so as to constrain the movable contact part to return towards the static contact part.

Preferably, the movable contact part is a plate-shaped structure, and the restraint frame spans over the plate-shaped movable contact part to restrain the movable contact part from returning to the static contact part.

Wherein, preferably, the switching device is a direct current high voltage relay.

The utility model has the following beneficial effects: the piston is provided with the non-return structure of the piston, so that the piston can be extruded from the bottom of the bottom shell but cannot rebound again after being stopped by the non-return structure, the piston can be clamped in time, and energy loss caused by rebound of the piston is reduced.

Drawings

Fig. 1 is a cross-sectional view of a relay having a pyrotechnic excitation device in embodiment 1 (the relay is in an open state);

FIG. 2 is a schematic view of the pyrotechnic excitation device of example 1 inserted and fixedly attached to a ceramic cover;

FIG. 3 is an exploded view of the structure of a pyrotechnic excitation device in example 1;

FIG. 4 is a sectional view of a pyrotechnic excitation device in accordance with embodiment 1;

FIG. 5 is an exploded view (front view) of the structure of the exciter in example 1;

FIG. 6 is an exploded view (perspective view) of the structure of the exciter in example 1;

fig. 7 is a sectional view of a relay having a pyrotechnic excitation device in embodiment 1 (the relay is in a conductive state);

FIG. 8 is a cross-sectional view of a relay having a pyrotechnic excitation device (pyrotechnic excitation device excitation) in example 1;

fig. 9 is a schematic view of the bottom case in embodiment 1;

FIG. 10 is a schematic view of the case of example 1 being flared to form a cusp-type backstop to limit piston rebound;

FIG. 11 is a schematic perspective view of a putter assembly according to embodiment 1;

fig. 12 is an exploded view of the structure of the push rod assembly of embodiment 1;

FIG. 13 is a schematic view (front view) of the restraint frame flattened by the impact of the piston in example 1;

FIG. 14 is a schematic view (perspective view) showing the restraint frame flattened by the impact of the piston in example 1;

FIG. 15 is a schematic view of a piston in embodiment 2;

FIG. 16 is a schematic view showing the case of example 2 being flared to form a cusp-type check to limit piston rebound;

FIG. 17 is a schematic view of a piston in embodiment 3;

FIG. 18 is a schematic view of a possible structure of the piston in embodiment 4;

fig. 19 is a schematic view of another possible structure of the piston in embodiment 4.

Detailed Description

To further illustrate the various embodiments, the utility model provides the accompanying drawings. The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments of the utility model and, together with the description, serve to explain the principles of the embodiments. Those skilled in the art will appreciate still other possible embodiments and advantages of the present invention with reference to these figures. Elements in the figures are not drawn to scale and like reference numerals are generally used to indicate like elements.

The utility model will now be further described with reference to the accompanying drawings and detailed description.

Example 1:

referring to fig. 1-2, as a preferred embodiment of the present invention, a relay with a pyrotechnic excitation device is provided, which includes a relay body 100 and a pyrotechnic excitation device 5 mounted and attached on the relay body 100, where the relay body 100 includes a stationary contact 1 (as a stationary contact) and a movable contact 2 (as a movable contact) for realizing connection or disconnection of the relay body 100, the relay body 100 further includes an outer housing 3, one end of the stationary contact 1 is exposed out of the outer housing 3 and electrically connected to an external load, and the other end of the stationary contact extends into the outer housing 3, and the movable contact 2 is disposed inside the outer housing 3 and connected to an electromagnetic driving mechanism 4. Wherein, static contact 1 is equipped with the internal thread, can be used for with external wiring end threaded connection fixed. The movable reed 2 is a bridge type movable reed, under the action of the electromagnetic driving mechanism 4, the movable reed 2 can move relatively close to or far away from the static contacts 1, and when the movable reed 2 is simultaneously contacted with the two static contacts 1, the communication of loads is realized. For convenience of description, it is defined that the fixed contact 1 is relatively located above the movable spring plate 2, and the movable spring plate 2 is relatively located below the fixed contact 1.

The relay body 100 further comprises a ceramic cover 6, the ceramic cover 6 is fixedly arranged inside the outer shell 3 and covers the lower end of the static contact 1 and the movable contact spring 2 (i.e. covers the contact point between the static contact 1 and the movable contact spring 2 and each other) to form a contact inner cavity, the contact point between the static contact 1 and the movable contact spring 2 is isolated from the outside air through the ceramic cover 6 to obtain high voltage resistance, and the relay can effectively ensure low contact resistance, long service life and high reliability. And when the relay is in short circuit, the arc resistance and high temperature resistance of the ceramic material can ensure that a loop under the short circuit arc is safe and reliable.

The outer casing 3 further comprises a base 32 and an upper cover 31 which are combined, the ceramic cover 6 is arranged inside the upper cover 31, the pyrotechnic excitation device 5 is fixedly connected to the ceramic cover 6 by being inserted from the outside of the ceramic cover 6, the lower end of the pyrotechnic excitation device 5 extends into a contact inner cavity in the ceramic cover 6 to be right above the movable contact spring piece 2, and the upper cover 31 is covered on the ceramic cover 6 and the pyrotechnic excitation device 5 to complete the integral assembly of the relay. Referring to fig. 2, the pyrotechnic actuator 5 is an independent modular structure, and has a substantially cylindrical revolving structure, the upper end of the ceramic cover 6 is provided with a plug hole 61, and the lower end of the pyrotechnic actuator 5 passes through the plug hole 61 to extend into the contact cavity. The pyrotechnic excitation device 5 may be fixed to the ceramic cover 6 by welding, riveting, screwing, or the like, and in this embodiment, the pyrotechnic excitation device 5 is fixed to the ceramic cover 6 by brazing. In addition, in this embodiment, the top surface of the upper cover 31 has a through hole and a hollow cylindrical section which are abducted and matched with the two static contacts 1 and the one pyrotechnic excitation device 5, so that the top ends of the two static contacts 1 can be exposed out of the outer shell 3, and the exterior of the pyrotechnic excitation device 5 can be covered and protected. In addition, in order to improve electrical safety, protective baffles (not shown due to angle problems) are respectively extended from two sides of the outer wall of the hollow cylindrical section in a direction perpendicular to the paper surface of the figure. In other embodiments, the pyrotechnic excitation device 5 may also be fixedly connected to the outer housing 3, but in this embodiment, the pyrotechnic excitation device 5 is selectively and fixedly connected to the ceramic cover 6, so that the assembly process can be simplified, and the pyrotechnic excitation device 5 and the stationary contact 1 are fixedly assembled on the ceramic cover 6 and then the upper cover 31 is covered during final assembly.

Referring to fig. 3-6, pyrotechnic activation device 5 specifically includes an activator 51, a piston 52, and a base 53. The actuator 51 and the bottom case 53 are engaged and fixed one above the other, and the piston 52 is accommodated between the actuator 51 and the bottom case 53. Wherein the initiator 51 further comprises a hollow initiator base 512, and a connector 511, an igniter 513 and a sealing ring 514 fixedly mounted inside the initiator base 512. The exciter base 512 and base 53 engage to form the outer housing of the pyrotechnic exciter 5. The connector 511, the igniter 513, the sealing ring 514 and the piston 52 are sequentially disposed inside the outer housing from top to bottom, and the connector 511 is connected to the lead 5131 of the igniter 513. The connector 511 is clamped and fixed on the inner wall of the exciter base 512, the sealing ring 514 is pressed into the exciter base 512 in an interference manner and upwards compresses and fixes the igniter 513, the upper end and the lower end of the piston 52 are respectively supported by the sealing ring 514 and the bottom shell 53, the sealing ring 514 can achieve the effects of moisture prevention and air sealing, and the igniter 513 above the piston can be further compressed and the piston 52 below the piston can be further compressed by micro deformation generated by compression of the sealing ring 514, so that vibration and loosening are prevented.

Referring to fig. 7-8, the connector 511 is used for fixedly connecting the ignition lead of the monitoring and excitation circuit to transmit the excitation electrical signal emitted by the monitoring and excitation circuit to excite the igniter 513, and the monitoring and excitation circuit may emit the excitation electrical signal to conduct downward via the connector 511 after the monitoring current value (or the current climbing rate) reaches a certain threshold, and excite the igniter 513 to ignite. An air gap 50 is arranged between the piston 52 and the igniter 513, and after the igniter 513 ignites gunpowder, high-pressure gas is generated in the air gap 50 (namely, ignition is carried out), so that the piston 52 is pushed to downwards break through the bottom shell 53, the piston 52 pushes the movable spring piece 2 to downwards move, the movable spring piece 2 is helped to be separated from the contact with the static contact 1, and the quick breaking of the relay is realized.

The bottom case 53 is a hollow cylindrical structure, and the piston 52 is a rotary structure with a shaft hole fitted inside the bottom case 53, so that the bottom case 53 can provide a guiding function for the piston 52, and the piston 52 moves downward along the hollow cylindrical inner cavity of the bottom case 53 after the ignition tool 513 ignites.

In this embodiment, the pyrotechnic actuator 5 is a modular structure that is independent of the relay body, and can be separately manufactured and then fixedly mounted to the relay. Production, the transportation of fireworks formula excitation device 5 are easily managed and controlled, and part is small in quantity, easily assembly, and the standardization of spare part also changes the realization, reaches to fall heavy this and carries the performance purpose. And a lead 5131 extending from the ignition tool 513 is connected with the ignition lead of the monitoring excitation circuit through the connector 511, so that the distance between the gunpowder in the ignition tool 513 and the leading-out end of the ignition lead is far, the temperature rise is low, and the temperature resistance requirement of the medicament is reduced.

Referring to fig. 9-10, the bottom of the bottom shell 53 is provided with staggered slits having a shape of a Chinese character mi, when the piston 52 impacts the bottom shell 53 downwards, the bottom of the bottom shell 53 expands outwards from the intersection point of the slits having a shape of a Chinese character mi and forms a sharp-tooth-shaped non-return portion 53-1 to abut against the peripheral surface or end of the piston 52 (if the piston 52 does not completely impact the bottom shell 53, the non-return portion 53-1 abuts against the peripheral surface of the piston 52 to stop the piston 52, and if the piston 52 completely impacts the bottom shell 53, the non-return portion 53-1 abuts against the end of the piston 52 to stop the piston 52) to stop the rebound of the piston 52. That is to say, under the check structure of the zigzag slit in the shape of a Chinese character 'mi', the piston 52 can be extruded from the bottom of the bottom shell 53, but cannot rebound again after being stopped by the check portion 53-1, the piston 52 can be clamped in time, energy loss caused by rebound of the piston 52 is reduced, and meanwhile, after the piston 52 is stopped, the head of the piston 52 is dead against the movable contact spring, so that the possibility of reclosing the movable contact and the static contact is avoided.

The bottom of the bottom shell 53 may have other shapes, such as a cross shape, in addition to the shape of a Chinese character 'mi' in the present embodiment. However, any shape of slit that causes the bottom of the bottom case 53 to expand outward after an impact is possible.

And, it is worth to say that the pyrotechnic excitation device with the check structure of the present embodiment may not be installed on the relay body as a separate modular structure, but integrated inside the relay as in the prior art, and fixed integrally with the relay. The pyrotechnic excitation device with the non-return structure can obviously improve the electrical safety performance of the relay, and the structure and the installation mode of the pyrotechnic excitation device are not necessarily related.

As a preferred example, the pyrotechnic excitation device 5 in this embodiment is applied to a ceramic-sealed relay, and specifically, the pyrotechnic excitation device 5 is welded to the ceramic cover 3, so that the welding tightness is good, the sealing performance and the anti-vibration performance of the pyrotechnic excitation device 5 are better, the outer shell of the pyrotechnic excitation device 5 is simpler to form, and the product height is lower. In other embodiments, the pyrotechnic excitation device 5 may also be applied to relays with other structures, as long as a plug hole (such as the plug hole 61 of the embodiment) is formed on the relay body for the insertion of the pyrotechnic excitation device 5, and the pyrotechnic excitation device 5 is attached to the relay through a fixed connection means. The pyrotechnic excitation device 5 can also be detachably connected (e.g., screwed) to be fixed to the relay body, so that the pyrotechnic excitation device 5 can be quickly replaced according to input requirements.

As shown in fig. 8, an arc extinguishing medium 54 is further disposed in the bottom shell 53, and when the pyrotechnic excitation device 5 is excited, the bottom shell 53 is broken downward by the piston 52 to release the arc extinguishing medium 54 into the contact cavity of the ceramic cover 6, so as to perform arc extinguishing treatment on the contact gap between the stationary contact 1 and the movable contact spring 2, further accelerate the arc extinguishing capability when the contact is disconnected, and improve the safety of short circuit of the product. In this embodiment, the arc-extinguishing medium 54 is quartz sand. Because the gas at the lower end of the pyrotechnic excitation device 5 expands rapidly after ignition and explosion, the arc-extinguishing medium 54 stored in the bottom shell 53 or the piston 52 can be uniformly and extremely rapidly spread in the contact inner cavity along with the explosive gas, and is not limited by the shapes of the static contact 1 and the movable contact piece 2 and the inner contour of the contact inner cavity to the greatest extent, so that the arc-extinguishing effect can be directly exerted in a short time.

The electromagnetic driving mechanism 4 is used for driving the movable reed 2 to move, referring to fig. 7-8, the electromagnetic driving mechanism 4 specifically includes a stationary iron core 41, a coil 42, a movable iron core 43, a push rod assembly 44, a return spring 45, a first yoke iron piece 46, a second yoke iron piece 47 and a magnetic conduction cylinder 48, the first yoke iron piece 46, the second yoke iron piece 47 and the magnetic conduction cylinder 48 are used for transmitting magnetic lines and improving the magnetic energy utilization rate, the lower end of the push rod assembly 44 is fixedly connected with the movable iron core 43, and the upper end of the push rod assembly is in linkage connection with the movable reed 2. The return spring 45 has one end acting on the stationary iron core 41 and the other end acting on the movable iron core 43. The coil 42 is electrified to enable the static iron core 41 to attract the movable iron core 43 to move upwards, and the push rod 44 pushes the movable reed 2 upwards to move upwards; when the coil 42 is deenergized, the electromagnetic drive mechanism 4 is reset by the elastic force of the reset spring 45. The electromagnetic driving mechanism 4 is a conventional direct-acting magnetic circuit structure, and the operation principle thereof is not described in detail in this example.

Referring to fig. 11 to 12, the push rod assembly 44 includes a push rod 441, a spring seat 442, and a U-shaped support 443, the push rod 441 is used to output the driving force of the electromagnetic driving mechanism 4, and the lower end thereof is fixedly connected to the movable iron core 43, and the upper end thereof is fixedly connected to the spring seat 442. The U-shaped support 443 is a plate-shaped structure and includes a top plate 4431 horizontally disposed above the spring seat 442 and two side plates 4432 connected to two ends of the top plate 4431 and extending downward, wherein lower ends of the two side plates 4432 are fixedly connected to two ends of the spring seat 442, so that the spring seat 442 and the U-shaped support 443 are connected to form a rectangular hollow restraint frame 400. The lower end of the over travel spring 445 abuts against the spring seat 442, and the movable spring plate 2 penetrates through the restraint frame 400 and abuts against the top plate 4431 under the elastic force of the over travel spring 445, so that the over travel spring 445 and the movable spring plate 2 are stably installed in the restraint frame 400 by the elastic force of the over travel spring 445. And, when push rod subassembly 44 pushes movable contact 2 and static contact 1 upwards and contacts, spring holder 442 can further compress over travel spring 445, has realized the overtravel of the contact under the relay on-state.

Referring to fig. 13-14, in the present embodiment, the spring seat 442 and the U-shaped support 443 are used to form a restraint frame 400, when the pyrotechnic excitation device 5 is excited, the piston 52 impacts downward on the restraint frame 400, so that the push rod assembly 44 and the movable spring 2 move downward, after the spring seat 442 is stopped by the internal structure of the relay, the over travel spring 445 is further compressed under the impact force of the piston 52, the two side plates 4432 of the U-shaped support 443 are pressed and bent to generate plastic deformation, so that the whole restraint frame 400 is flattened and cannot be restored, and thus the heights of the whole push rod assembly 44 and the movable spring 2 are further reduced, and the U-shaped support 443 straddles over the plate-shaped movable spring 2, so that the movable spring 2 can be restrained from rebounding back towards the stationary contact 1. And because the piston 52 impacts downwards, the restraint frame 400 is compressed and flattened, the contact gap between the movable spring leaf 2 and the static contact 1 can be further pulled open, and the short-circuit safety is improved. From another perspective, since the restraint frame 400 formed by the spring seat 442 and the U-shaped support 443 in this embodiment can be compressed and flattened, compared with other schemes in which the push rod assembly cannot be compressed and flattened, when the push rod assembly 44 and the movable spring plate 2 in this embodiment are impacted by the piston 52, only a smaller downward movement distance (after the restraint frame 400 is overlapped and flattened and compressed in the compression space) is required to ensure that a sufficiently large contact gap is opened, so the height space of the contact cavity of the ceramic cover 6 can also be set to be smaller, and can be kept consistent with the specification of a relay without the pyrotechnic excitation device 5 (the existing relay with the pyrotechnic excitation device 5 needs to increase the height space of the contact cavity), and thus the height volume of the whole relay can also be reduced.

Preferably, the U-shaped support 443 is made of a non-deformation-restoring material, such as stainless steel or mild steel. In addition, the side plate 4432 is a hollow sheet structure in this embodiment, so that the side plate 4432 is more easily pressed and bent.

In addition to the constraint frame 400 of this embodiment for limiting the movable spring 2 and constraining the movable spring 2 to rebound toward the stationary contact 1, in other embodiments, other constraint elements may be used instead of the constraint frame 400, for example, the movable spring 2 is fixedly connected to the end of a strut, but the strut is designed to receive impact to generate axial compression and not recover deformation. It is possible that the constraining member is a structure coupled with the movable spring plate 2 and configured to constrain the movable spring plate 2 to return toward the stationary contact 1.

In addition, because the non-return structure of the piston 52 is arranged in the embodiment, on one hand, the non-return structure enables the piston 52 to be clamped in time after being flushed out of the bottom case 53, the piston 52 cannot be collided and rebounded, the restraint frame 400 can prevent the movable spring leaf 2 from rebounding, and the movable spring leaf and the static spring leaf can both play a role in avoiding reclosing of the movable contact and the static contact, so that double insurance is realized; on the other hand, the non-return structure prevents the piston 52 from rebounding, so that the energy loss caused by the rebounding of the piston 52 is reduced, most of the kinetic energy of the piston 52 can act on the restraint frame 400, and the restraint frame 400 can be guaranteed to be impacted and flattened. Because the energy loss of the rebound of the piston 52 is reduced, the impact force requirement of the piston 52 of the embodiment can be reduced, so that the amount of the explosive of the embodiment can be reduced, and the safety performance is improved.

The present embodiment illustrates the function and effect of the pyrotechnic actuator 5 and the plunger assembly 44 in a relay structure, and the same structure can be applied to other switching devices, such as a contactor, in addition to the relay.

Example 2:

this embodiment proposes a relay, which is similar in structure to the relay of embodiment 1, and also includes a bottom case 53 having a slit shaped like a Chinese character mi at the bottom, except for the piston structure of this embodiment. As shown in fig. 15-16, in the present embodiment, a neck portion 52A-1 with a reduced diameter is provided on the piston 52A, when the piston 52A breaks the bottom shell 53 downward, the bottom of the bottom shell 53 expands outward from the intersection point of the slit in the shape of a Chinese character mi to form a pointed tooth-shaped non-return portion 53-1, and when the piston 52A impacts the movable spring to rebound, the lower end step of the neck portion 52A-1 is stopped by the non-return portion 53-1 to be limited.

In the present embodiment, the neck portion 52A-1 with a reduced diameter is provided on the piston 52A, so that the piston 52A can abut against the lower end step of the neck portion 52A-1 to generate a check effect on the piston 52A, and therefore, the piston 52A of the present embodiment can be stably abutted against a check by the check portion 53-1 even if the piston 52A does not completely flush out of the bottom case 53. Therefore, the stroke and impact force requirements of the piston 52A of the present embodiment can be reduced, so that the amount of the fire can be reduced, and the safety performance is improved.

Example 3:

this embodiment proposes a relay, which is similar in structure to the relay of embodiment 1, and also includes a bottom case 53 having a slit shaped like a Chinese character mi at the bottom, except for the piston structure of this embodiment. Referring to fig. 17, in the present embodiment, the piston 52B is divided into two independent sections, namely, an upper piston 52B-1 and a lower piston 52B-2, when the pyrotechnic actuator is not activated, the upper piston 52B-1 and the lower piston 52B-2 are stacked up and down, and when the pyrotechnic actuator is activated, the lower piston 52B-2 is pushed out of the bottom case 53C, and the upper piston 52B-1 remains in the bottom case 53C, so that the check portion 53C-1 of the bottom case 53C abuts against and limits the end of the lower piston 52B-2. In this embodiment, similarly to embodiment 2, a radial step structure is formed on the piston, in embodiment 2, the step in the radial direction of the piston is formed by the reduced diameter portion, and in this embodiment, the piston is divided into two independent sections to form the radial step. The effect can be seen in example 2.

Example 4:

this embodiment proposes a relay, the structure of which is similar to that of the relay of embodiment 3, and which also includes a bottom shell 53 having a slit shaped like a Chinese character mi at the bottom and a piston divided into two parts, the only difference being that: in the embodiment, the piston is in a shape that the piston contracts from top to bottom (namely towards the direction that the piston breaks the bottom shell), the force application area of the piston is reduced, and the acting force on the bottom shell and the movable spring piece is enhanced, so that the bottom shell can be broken more quickly, and the movable spring piece can be pushed to be broken rapidly. The shape of the piston lower end contraction can be realized by adopting a conical contraction structure, a step-shaped contraction structure or a combination of the conical contraction structure and the step-shaped contraction structure, and the piston with the contracted lower end as shown in fig. 18 and 19 is feasible.

While the utility model has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the utility model as defined by the appended claims.

Claims (11)

1. Pyrotechnic composition formula excitation device, including exciter, piston and drain pan, the drain pan is hollow structure, the piston cooperation is installed in the drain pan, the exciter ignites gunpowder and promotes through the gas the piston breaks through the drain pan, its characterized in that: the bottom shell is provided with a non-return structure, and after the piston breaks through the bottom shell, the non-return structure prevents the impact rebound of the piston.

2. The pyrotechnic excitation device as claimed in claim 1 wherein: the bottom of the bottom shell is provided with a plurality of staggered cracks, after the piston breaks through the bottom shell, the bottom of the bottom shell expands outwards from the intersection points of the cracks to form a sharp-tooth-shaped non-return part, and the sharp end of the non-return part abuts against the piston to prevent the piston from rebounding.

3. A pyrotechnic excitation device in accordance with claim 2 wherein: the crack is shaped like a Chinese character ' mi ' or a cross '.

4. A pyrotechnic excitation device in accordance with claim 2 wherein: and a radial section difference structure is arranged on the piston.

5. A pyrotechnic excitation device in accordance with claim 4 wherein: the piston is provided with a neck part with a diameter reduction, and the tip end of the non-return part is abutted against a step at one end of the neck part to prevent the piston from rebounding; or the piston is divided into two independent sections and comprises an upper piston and a lower piston, after the lower piston breaks the bottom shell, the upper piston is still remained in the bottom shell, and the tip of the non-return part is propped against the end part of the lower piston to prevent the lower piston from rebounding.

6. The pyrotechnic excitation device as claimed in claim 1 wherein: the piston is a structure which gradually shrinks towards the direction of breaking the bottom shell.

7. Switch apparatus with pyrotechnic composition excitation device, including switch apparatus body and pyrotechnic composition excitation device set up on the switch apparatus body, the switch apparatus body includes fixed static contact and movable contact part in order to carry out the switch function, the pyrotechnic composition excitation device according to the load condition of the switch apparatus body ignites gunpowder and produces and promotes the movable contact part and keep away from the explosion impact force of static contact part, in order to assist the quick disconnection of switch apparatus, its characterized in that: the pyrotechnic excitation device is as claimed in any of claims 1 to 6.

8. Switching device with pyrotechnic excitation device according to claim 7, characterized in that: the piston is arranged at a position corresponding to the position where the piston breaks through the bottom shell, the restraint part is configured to restrain the movable contact part from returning towards the static contact part and being coupled with the movable contact part for assembly, and the restraint part is made of a material which can receive the impact of the piston and does not restore to deform.

9. Switching device with pyrotechnic excitation device according to claim 8, characterized in that: the constraint piece is a constraint frame, and the constraint frame is smashed to be flat without recovering deformation after receiving the impact of the piston, so that the movable contact part is constrained to return towards the static contact part.

10. Switching device with pyrotechnic excitation device according to claim 9, characterized in that: the movable contact part is of a plate-shaped structure, and the restraint frame is arranged on the plate-shaped movable contact part in a spanning mode to restrain the movable contact part from returning to the static contact part.

11. Switching device with pyrotechnic excitation device according to claim 7, characterized in that: the switching device is a direct-current high-voltage relay.

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