CN110828228B

CN110828228B - Vacuum interrupter contact protection device

Info

Publication number: CN110828228B
Application number: CN201911034981.0A
Authority: CN
Inventors: 覃向阳
Original assignee: Zhejiang Taikong Electric Co ltd
Current assignee: ZHEJIANG TAIKONG ELECTRIC Co.,Ltd.
Priority date: 2019-10-29
Filing date: 2019-10-29
Publication date: 2021-06-08
Anticipated expiration: 2039-10-29
Also published as: CN110828228A

Abstract

The invention relates to the technical field of power equipment, and discloses a contact protection device of a vacuum arc extinguish chamber, which comprises an insulating cover, a main shielding cover, a static contact and a moving contact, wherein the inner wall of one side of the main shielding cover is fixedly connected with a suction pipe, the inner wall of the suction pipe is fixedly provided with a sealing piston, a plunger rod is arranged inside the suction pipe, the plunger rod is movably sleeved with the sealing piston, and the upper end and the lower end of the plunger rod are respectively and fixedly connected with an upper plunger and a lower plunger. According to the invention, the heat collection box and the suction pipe are respectively arranged on the two sides of the contact, on one hand, partial metal steam is timely received through the side edge of the heat collection box, on the other hand, after the heat collection box absorbs heat, internal gas expands to push the lower plunger to move downwards, so that the similar injector consisting of the upper plunger and the suction pipe can timely suck the metal steam near the contact, and by matching with the heat collection box, the content of the metal steam at the contact can be rapidly reduced, the amount of the metal steam falling back to the surface of the contact is greatly reduced, and the use safety of the contact is protected.

Description

Vacuum interrupter contact protection device

Technical Field

The invention relates to the technical field of power equipment, in particular to a contact protection device of a vacuum arc extinguish chamber.

Background

The arc is a form of gas discharge, which is divided into self-sustaining discharge and non-self-sustaining discharge, and in vacuum, a vacuum arc is maintained by metal vapor, for a contact electrical appliance, as the arc is mainly generated when a contact breaks a circuit, high temperature will burn the contact and insulation, and even cause interphase short circuit and electrical appliance explosion under severe conditions, thus causing fire and endangering the safety of personnel and equipment. Therefore, the arc extinguishing device is installed on the electric appliance with high voltage and frequent switching on and off, so that the safety of the equipment is protected.

The basic structure of the vacuum arc extinguish chamber comprises an insulating cover 1, a main shielding cover 2, a static contact 3 and a moving contact 4 in figure 1, wherein the moving contact 4 is movably sleeved with the insulating cover 1 and is in sealing connection through a metal corrugated pipe. At the moment of just separating the contacts, vacuum electric arc is generated between the contacts immediately, the vacuum electric arc is maintained by metal steam evaporated from the contacts, the metal steam is close to and stops evaporating until the power frequency alternating current is close to zero, simultaneously, plasma of the vacuum electric arc is quickly diffused to the periphery, the electric arc is extinguished, the gap between the contacts is quickly changed into an insulator, and then the current is cut off.

At present, for metal steam in a vacuum arc extinguishing chamber, the pressure of the generated gas is higher than that of the edge of the metal steam and the metal steam diffuses to the periphery, and because the power-off instant is extremely short and is basically in the millisecond level, the diffusion capacity of the metal steam to a peripheral shielding cover is limited, a considerable part of the metal steam can directly fall on the surface of a contact, the surface of the contact is uneven, poor contact is caused, the voltage of a main loop is reduced, the load is easily heated and overloaded, and the contact is easily burnt out, so that the contact protection device is provided and aims to solve the problems.

Disclosure of Invention

Aiming at the defects of the existing vacuum arc-extinguishing chamber contact in the use process, the invention provides a vacuum arc-extinguishing chamber contact protection device which has the advantage of protecting the contact to be safe to use and solves the problems in the background technology.

The invention provides the following technical scheme: a contact protection device of a vacuum arc extinguish chamber comprises an insulating cover, a main shielding cover, a static contact and a moving contact, a suction pipe is fixedly connected with the inner wall of one side of the main shielding cover, a sealing piston is fixedly arranged on the inner wall of the suction pipe, a plunger rod is arranged in the suction tube and movably sleeved with the sealing piston, the upper end and the lower end of the plunger rod are respectively and fixedly connected with an upper plunger and a lower plunger, the upper plunger and the lower plunger are both connected with the inner part of the suction pipe in a sliding way, the bottom end of the lower plunger is fixedly connected with a return spring, the other end of the return spring is fixedly connected with the inner bottom of the suction pipe, the inner wall of the other side of the main shielding cover is fixedly connected with a heat collecting box, the inner cavity of the heat collection box is communicated with the upper end of the inner cavity between the sealing piston and the lower plunger through an air pipe, and one side of the heat collection box and the top end of the suction pipe are respectively positioned at the left side and the right side of the static contact.

Preferably, one side of the heat collecting box facing the static contact is provided with a semicircular concave arc surface, and the concave arc surface is provided with a transverse aggregate rib.

Preferably, the top end of the suction pipe is provided with a collecting hopper, and the bottom end of the collecting hopper extending into the suction pipe is radially contracted to be in an inverted round table shape.

Preferably, the contact surface between the sealing piston and the plunger rod adopts a cup piston in a downward direction.

The invention has the following beneficial effects:

1. according to the invention, the heat collection box and the suction pipe are respectively arranged on the two sides of the contact, on one hand, partial metal steam is timely received through the side edge of the heat collection box, on the other hand, after the heat collection box absorbs heat, internal gas expands to push the lower plunger to move downwards, so that the similar injector consisting of the upper plunger and the suction pipe can timely suck the metal steam near the contact, and by matching with the heat collection box, the content of the metal steam at the contact can be rapidly reduced, the amount of the metal steam falling back to the surface of the contact is greatly reduced, and the use safety of the contact is protected.

2. According to the invention, the side surface of the heat collection box facing the contact is designed into the semi-circular concave shape, and the horizontal aggregate ribs are arranged on the surface of the concave arc, so that on one hand, the bearing area is increased, metal steam diffused to the periphery can be collected in time, meanwhile, the contact area is increased, the heat collection performance can be improved, gas in the heat collection box can conveniently make thermal expansion reaction in time, and the action effect of the suction pipe is initiated.

3. According to the invention, the collecting hopper is arranged at the top end of the suction pipe, and the bottom end of the collecting hopper contracts along the radial direction, so that collected steam is prevented from entering the inner wall of the suction pipe to influence the sealing performance of the upper plunger and the inner wall of the suction pipe.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a top view of the heat collecting tank of the present invention;

fig. 3 is a right side view of fig. 2 of the present invention.

In the figure: 1. an insulating cover; 2. a main shield case; 3. static contact; 4. a moving contact; 5. a suction tube; 6. a sealing piston; 7. a plunger rod; 8. an upper plunger; 9. a lower plunger; 10. a return spring; 11. a heat collection tank; 11a, aggregate ribs; 12. a collection hopper.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-3, a contact protection device for a vacuum arc-extinguishing chamber comprises an insulating cover 1, a main shielding cover 2 is fixedly connected to the top end of an inner cavity of the insulating cover 1, a fixed contact 3 and a movable contact 4 are respectively arranged at the upper end and the lower end of the insulating cover 1, a suction tube 5 is fixedly connected to the inner wall of one side of the main shielding cover 2, a sealing piston 6 is fixedly installed on the inner wall of the suction tube 5, a plunger rod 7 is arranged inside the suction tube 5, the plunger rod 7 is movably sleeved with the sealing piston 6, an upper plunger 8 and a lower plunger 9 are respectively fixedly connected to the upper end and the lower end of the plunger rod 7, the upper plunger 8 and the lower plunger 9 are respectively located at the upper side and the lower side of the sealing piston 6, the upper plunger 8 and the lower plunger 9 are both connected with the inside of the suction tube 5 in a sliding manner and are both sealed, a heat collecting tank 11 is fixedly connected to the inner wall of the other side of the main shielding case 2, the inner cavity of the heat collecting tank 11 is communicated with the upper end of the inner cavity between the sealing piston 6 and the lower plunger 9 through an air pipe, and one side of the heat collecting tank 11 and the top end of the suction pipe 5 are respectively positioned at the left side and the right side of the static contact 3.

Therefore, when the static contact 3 and the moving contact 4 generate metal steam due to vacuum arc, part of the metal steam is directly diffused to the surface of the heat collection box 11, and high temperature near the vacuum arc can expand gas in the heat collection box 11 and enter the suction pipe 5 to push the lower plunger 9 to move downwards to drive the upper plunger 8 to move downwards, at the moment, the metal steam diffused to the side of the suction pipe 5 forms a suction effect due to the downward movement of the upper plunger 8, so that more metal steam is gathered at the top end of the inner cavity of the suction pipe 5, therefore, the heat collection box 11 is matched with the suction effect at the suction pipe 5, the metal steam generated at the static contact 3 and the moving contact 4 can be timely absorbed, only a small amount of metal steam exists at the static contact 3 and the moving contact 4, namely, the amount of the metal steam falling on the contact is reduced. Because all the mechanisms are good thermal conductors, the temperature of the suction pipe 5 and the heat collection box 11 is reduced after the temperature of the short-term metal steam is high, the metal steam is condensed, the air pressure in the heat collection box 11 is gradually recovered, and the return spring 10 pushes the lower plunger 9 to move upwards.

Wherein, one side of the heat collecting box 11 facing the static contact 3 is set to be a semicircular concave arc surface, and a transverse collecting rib 11a is arranged on the concave arc surface, the collecting rib 11a can condense metal steam more easily, and meanwhile, the heat collecting performance is improved by improving the contact area.

Wherein, be equipped with collection hopper 12 at the top of suction tube 5, collection hopper 12 stretches into the radial shrink of the bottom in the suction tube 5 for collection hopper 12 is the circular truncated cone of inversion, so that collection hopper 12 absorbs the metal vapor of suction phase, prevents that metal vapor from directly reaching the inner wall of suction tube 5 and condensing and influence the sliding seal performance of plunger 8 and suction tube 5.

The contact surface between the sealing piston 6 and the plunger rod 7 adopts a downward leather cup piston, the pressure in the suction pipe 5 is always higher than that in the insulating cover 1 due to the vacuum in the insulating cover 1, and the downward leather cup piston can enable the sealing piston 6 and the plunger rod 7 to have good sealing performance all the time.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides a vacuum interrupter contact protection device, includes insulating boot (1), main shield cover (2), static contact (3) and moving contact (4), its characterized in that: the inner wall of one side of the main shielding cover (2) is fixedly connected with a suction pipe (5), the inner wall of the suction pipe (5) is fixedly provided with a sealing piston (6), a plunger rod (7) is arranged in the suction pipe (5), the plunger rod (7) is movably sleeved with the sealing piston (6), the upper end and the lower end of the plunger rod (7) are respectively fixedly connected with an upper plunger (8) and a lower plunger (9), the upper plunger (8) and the lower plunger (9) are both in sliding connection with the inner part of the suction pipe (5), the bottom end of the lower plunger (9) is fixedly connected with a return spring (10), the other end of the return spring (10) is fixedly connected with the inner bottom of the suction pipe (5), the inner wall of the other side of the main shielding cover (2) is fixedly connected with a heat collection box (11), the inner cavity of the heat collection box (11) is communicated with the upper end of the inner cavity between the sealing piston, one side of the heat collection box (11) and the top end of the suction pipe (5) are respectively positioned at the left side and the right side of the static contact (3).

2. A vacuum interrupter contact protection device according to claim 1, characterized by: one side of the heat collection box (11) facing the static contact (3) is provided with a semicircular concave arc surface, and a transverse aggregate rib (11a) is arranged on the concave arc surface.

3. A vacuum interrupter contact protection device according to claim 1, characterized by: the top of suction tube (5) is equipped with collecting hopper (12), collecting hopper (12) stretch into the radial shrink of bottom in suction tube (5) and are the round platform shape of inversion.

4. A vacuum interrupter contact protection device according to claim 1, characterized by: the contact surface between the sealing piston (6) and the plunger rod (7) adopts a cup piston in the downward direction.