Transverse magnetic field contact for vacuum arc-extinguishing chamber

Abstract

A transverse magnetic field contact for a vacuum arc-extinguishing chamber comprises a contact body, the contact body is provided with an arcing surface and an assembling surface, the arcing surface is provided with a plurality of rotating arc grooves which are uniformly distributed in the circumferential direction of the contact body and are arranged in a penetrating mode, and the contact body is allowed to be in a'hot wheel 'structure through the plurality of rotating arc grooves. The arc rotating grooves are formed in the arc burning surface, contact fingers matched with the arc rotating grooves in number are obtained, the arc moving direction is defined by the arc rotating grooves and the contact fingers, continuity is achieved in the moving direction, and groove edges used for being connected with the arc grooves and guiding part of the arc into the arc grooves are formed on the arc burning surface of the contact fingers. And surface edges which are used for connecting the peripheral surface of the contact finger and guiding part of electric arc to the peripheral surface of the contact finger are formed on the arcing surface and the assembling surface of the contact finger. The beneficial effects of the utility model lie in that the static state of the electric arc is reduced, the damage caused by the continuous burning of the electric arc to the arcing surface is reduced, the utilization rate of the arcing surface is also improved, and the whole contact body is really and uniformly covered.

Description

TECHNICAL FIELD

[0001] The utility model relates to vacuum switch technical field especially a transverse magnetic field contact for vacuum arc extinguishing chamber. BACKGROUND

[0002] The vacuum arc extinguishing chamber is the key element of the vacuum switch, and undertakes the task of extinguishing arc, and the closing and breaking of circuit current are completed by the contact in the vacuum arc extinguishing chamber.

[0003] The surface of the conventional vacuum arc extinguishing chamber contact usually adopts the radial straight groove form to produce the transverse magnetic field.

[0004] Defect one: the arc control ability is limited, and the concentrated arc is easy to form

[0005] When breaking the large current, the transverse magnetic field can not be enough to fully "blow away" the arc, that is, when the current exceeds a certain threshold, for example, 20kA, the arc can be converted from the diffusion state to the concentrated arc with high energy, and the arc temperature is extremely high, which can continuously ablate a local area on the surface of the contact like a welding gun, resulting in a large amount of evaporation and spatter of the contact material, and the serious local ablation can ignite the arc, resulting in arc failure after the current zero crossing, limiting the breaking capacity of a single arc extinguishing chamber, and shortening the service life of the contact.

[0006] Defect two: the utilization of the contact surface is uneven

[0007] The arc rotates on the surface of the contact, but the rotation path is relatively fixed, that is, the ablation area of the arc is mainly concentrated in one or several annular areas on the surface of the contact, and the utilization rate of the center and the outer edge of the contact is very low.

[0008] Defect three: the control ability of the transverse magnetic field on the small current arc is weak

[0009] The strength of the transverse magnetic field is proportional to the current size, that is, when breaking the small current such as a few amperes to a few hundred amperes, the generated magnetic field is very weak, and cannot effectively drive the arc to rotate. Utility model content

[0010] The utility model wants to solve the above-mentioned prior art's shortcomings, provide a vacuum interrupter with transverse magnetic field contact to solve the above-mentioned problem.

[0011] The utility model discloses a kind of vacuum interrupter with transverse magnetic field contact, including contact body, contact body has arc face, and assembly surface, arc face is formed with several arc rotation grooves on contact body, arc rotation groove is evenly distributed and is arranged through along the circumference of contact body, and allow through several arc rotation grooves to make contact body present "fire wheel" configuration, and get the contact finger matched with the number of arc rotation groove, arc rotation groove and the outer peripheral surface of contact finger define the movement direction of arc, and have continuity in movement direction, contact finger is formed with the slot rib on arc face and assembly surface, to link the outer peripheral surface of contact finger and guide part of arc to the outer peripheral surface of contact finger.

[0012] Further improvement, guiding surface is formed on contact finger and is inclinedly arranged between face edge and arc face.

[0013] Further improvement, arc rotation groove includes arc rotation corner section, two arc rotation arc sections respectively located on both sides of arc rotation corner section and two arc rotation straight sections respectively connected with corresponding arc rotation arc section, arc rotation straight section is used to link the outer peripheral surface of contact finger and arc rotation arc section.

[0014] Further improvement, arc rotation straight section and the outer peripheral surface of contact finger have arc transition section linking both.

[0015] Further improvement, the angle between arc rotation straight section and horizontal line is 10 °.

[0016] Further improvement, the angle between the central position of arc rotation arc section and horizontal line is 25 °.

[0017] Further improvement, contact body is made of copper-chromium alloy.

[0018] The utility model has the beneficial effects that:

[0019] The contact body of the utility model presents "fire wheel" configuration, so that arc can be quickly driven to rotate, further reduce the stationary state of arc, reduce the damage caused by the continuous burning of arc face, also improve the utilization rate of arc face, truly achieve uniform coverage of the entire contact body, thereby improve material utilization, under the same breaking capacity, smaller diameter contact can be used, realize the miniaturization and low cost of vacuum interrupter. DRAWINGS

[0020] Figure 1 It is the structural schematic diagram of the utility model. CONCRETE IMPLEMENTING METHOD

[0021] The utility model makes further illustration in connection with the drawings:

[0022] Referring to the drawings: this vacuum arc extinguish chamber uses transverse magnetic field contact, including contact body 1, contact body 1 has arc face 11 and assembly surface, arc face 11 is formed with several arc rotation grooves 13 that are evenly distributed along the circumference of contact body 1 and are arranged through on contact body 1, and allow through several arc rotation grooves 13 to make contact body 1 present "fire wheel" configuration, and get the number matching contact finger 14 of arc rotation groove 13, the outer circumferential surface of arc rotation groove 13 and contact finger 14 defines the movement direction of arc, and has continuity in the movement direction, the slot edge 15 that arc face 11 is formed with to link arc rotation groove 13 and guide part arc to arc rotation groove 13 is formed on arc face 11 and assembly surface with the outer circumferential surface of contact finger 14 and guide part arc to the outer circumferential surface of contact finger 14 is formed with the surface edge 16 that contact finger 14 is linked on the outer circumferential surface.The principle of the utility model lies in, according to right-hand screw rule, when short-circuit current passes, can produce very big tangential component through arc rotation groove 13, the outer circumferential surface of arc rotation groove 13 and contact finger 14 defines the movement direction of arc, and both have continuity in link, after the guidance of arc through arc rotation groove 13, it can reach the outer circumferential surface of corresponding contact finger 14 because contact body 1 presents round member, to make arc rotate movement along the circumferential direction of contact body 1, namely in arc area generates the radial magnetic field perpendicular to the direction of arc, namely transverse magnetic field, under the action of transverse magnetic field, arc moves at high speed on arc face 11, drives the metal vapor, metal ion and electron density of arc area close to the condition of diffusion type vacuum arc, so when current passes zero, arc face 11 can rapidly cool to the temperature that does not evaporate a large amount of metal vapor again, thus after arc extinguishing, the recovery speed of post-arc medium intensity greatly improves, can approach the recovery speed of post-arc medium intensity of diffusion type vacuum arc, when breaking small current, the depth of melting area is smaller, and metal vapor can solidify in very short time, and can stabilize arc, prevent its early extinguishing, significantly reduce the cut-off value, the generated overvoltage is lower, is more friendly to power system, especially suitable for the occasion that need to frequently operate inductive load;

[0023] And in order to increase the efficiency of the guide, the groove edge 15 and the surface edge 16 are also provided, on the one hand, the groove edge 15 guides part of the arc into the rotating arc groove 13, and the surface edge 16 guides part of the arc to the outer surface of the contact finger 14, so that the arc has filled the contact body 1 around when the arc does not rotate, and then the arc driven by the rotating arc groove 13 can drive the arc around the contact body 1 to rotate in a certain direction, so as to quickly drive the arc to rotate, further reduce the static state of the arc, also reduce the damage caused by the continuous burning of the arc to the arc surface 11; on the other hand, it plays a limiting role, that is, through the groove edge 15 and the surface edge 16, the arc at the outer surface of the contact finger 14 and in the rotating arc groove 13 is limited to flow, that is, it will not run to the arc surface 11, avoiding the arc concentrated in a certain area of the arc surface 11 or flowing to the assembly surface, thereby increasing the durability of the contact body 1. In this embodiment, the groove edge 15 and the surface edge 16 are both chamfer transitions during processing, which can produce inclined surfaces that have a guiding effect.

[0024] Further improvement, the surface edge 16 and the arc surface 11 also have a guide surface 17 formed on the contact finger 14 and arranged obliquely, which on the one hand improves the uniform distribution efficiency of the arc, that is, by inclining, the guide surface 17 has a guiding effect, and part of the arc can exist at the outer edge of the arc surface 11, thereby improving the utilization rate of the arc surface 11, and truly achieving uniform coverage of the entire contact body 1, thereby improving material utilization, and under the same breaking capacity, a smaller diameter contact can be used, realizing the miniaturization and low cost of the vacuum arc chamber.

[0025] Further improvement, the rotating arc groove 13 includes a rotating arc corner segment 131, two rotating arc arc segments 132 respectively located on both sides of the rotating arc corner segment 131, and two rotating arc straight segments 133 respectively connected to the corresponding rotating arc arc segments 132, the rotating arc straight segments 133 are used to connect the outer surface of the contact finger 14 and the rotating arc arc segments 132, and the rotating arc corner segment 131 is used to transport the arc passing through it to the two rotating arc arc segments 132, based on the two rotating arc arc segments 132 being in a groove, the arc flowing along the rotating arc arc segments 132 is in the groove, and the guiding effect is enhanced, the rotating arc arc segment 132 is one of the guiding paths for guiding the arc to the outer surface of the contact finger 14, because the rotating arc arc segment 132 is arc-shaped, the arc-shaped direction is circumferential, that is, it will turn when it reaches a certain point, and it cannot rely on the rotating arc arc segment 132 alone, so a rotating arc straight segment 133 is connected, the basic effect of the rotating arc straight segment 133 is consistent with that of the rotating arc arc segment 132, which is to provide guidance, the only difference between the two is that the direction of the guidance provided by the rotating arc straight segment 133 is straight, and the arc will not turn under its guidance, and the arc is accurately guided to the outer surface of the contact finger 14.

[0026] Further improvement, the arc rotating linear segment 133 and the outer surface of the contact finger 14 have an arc transition segment 134 connecting both, the setting is considered to produce a sharp corner in the processing, the sharp corner will cause stress concentration and manufacturing difficulty, thereby affecting the safety and life of the structure, so as to eliminate it through the arc transition segment 134, and the arc transition segment 134 can also realize the fluency of arc steering, that is, the steering of the arc when it reaches the outer surface of the contact finger 14 through the arc rotating linear segment 133, so that the arc can quickly reach the outer surface of the contact finger 14.

[0027] Further improvement, the angle between the arc rotating linear segment 133 and the horizontal line is 10°; the angle between the center position of the arc segment 132 and the horizontal line is 25°. The arc rotating groove ensures stable arc movement, controllable direction, can generate sufficient and stable tangential electromagnetic force, drive the arc to rotate at high speed, balance the tangential force and the radial force, realize the uniform distribution of arc energy, reduce local ablation, prolong the life of the contact, promote the rapid diffusion and condensation of the post-arc metal vapor, speed up the recovery of medium strength, ensure reliable arc extinction, improve the performance, reliability and life of the vacuum arc chamber when breaking large current.

[0028] Further improvement, the contact body 1 is made of copper-chromium alloy.

[0029] Although the utility model has been illustrated and described by referring to the preferred embodiments, it should be understood by those skilled in the art that various changes in form and details can be made within the scope of the claims.

Claims

1. A transverse magnetic field contact for a vacuum interrupter comprising a contact body (1), characterized in that: The contact body (1) has an arc surface (11) and an assembly surface, the arc surface (11) is formed with a plurality of arc rotation grooves (13) on the contact body (1) and uniformly distributed along the circumference of the contact body (1) and arranged through, and allows the contact body (1) to be in a "fire wheel" configuration through the arc rotation grooves (13), and a number of contact fingers (14) matched with the number of the arc rotation grooves (13), the arc rotation grooves (13) and the outer circumferential surface of the contact fingers (14) define the movement direction of the arc and have continuity in the movement direction, the contact fingers (14) are formed with groove edges (15) on the arc surface (11) to connect the arc rotation grooves (13) and guide part of the arc into the arc rotation grooves (13), and the contact fingers (14) are formed with surface edges (16) on the arc surface (11) and the assembly surface to connect the outer circumferential surface of the contact fingers (14) and guide part of the arc to the outer circumferential surface of the contact fingers (14).

2. The transverse magnetic field contact for a vacuum interrupter according to claim 1, characterized in that: The surface edges (16) and the arc surface (11) further have a guide surface (17) formed on the contact fingers (14) and arranged obliquely.

3. The transverse magnetic field contact for a vacuum interrupter according to claim 1, characterized in that: The arc rotation groove (13) includes an arc rotation corner segment (131), two arc rotation arc segments (132) respectively located on both sides of the arc rotation corner segment (131), and two arc rotation straight line segments (133) respectively connected with the corresponding arc rotation arc segments (132), the arc rotation straight line segments (133) are used to connect the outer circumferential surface of the contact fingers (14) and the arc rotation arc segments (132).

4. The transverse magnetic field contact for a vacuum interrupter according to claim 3, characterized in that: The arc rotation straight line segments (133) and the outer circumferential surface of the contact fingers (14) have an arc transition segment (134) connecting both.

5. The transverse magnetic field contact for a vacuum interrupter according to claim 3, characterized in that: The included angle between the arc rotation straight line segment (133) and the horizontal line is 10°.

6. The transverse magnetic field contact for a vacuum interrupter according to claim 3, characterized in that: The included angle between the center position of the arc rotation arc segment (132) and the horizontal line is 25°.

7. The transverse magnetic field contact for a vacuum interrupter according to claim 1, characterized in that: The contact body (1) is made of copper-chromium alloy.

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