JP2016100108A - Dc current cut-off miniature switch with arc extinguishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a DC current cut-off miniature switch with an arc extinguishing device, capable of accurately extinguishing an arc by bypassing the arc generated when a direct current is cut off.SOLUTION: The DC current cut-off miniature switch with the arc extinguishing device is configured to guide an arc route, generated when a switch is switched off, to intentionally bypass to form a plurality of arc paths, so as to extend an open/close durable lifetime by increasing the number of the arc paths .SELECTED DRAWING: Figure 1

Description

  The present invention relates to a small switch for interrupting a direct current with an arc extinguishing device.

  2. Description of the Related Art Conventionally, as a direct current small switch for interrupting direct current, a small switch for interrupting direct current with an arc extinguishing device as described below (see Patent Document 1 and Patent Document 2 below) has been proposed.

  FIG. 8 is a perspective view showing a state of a conventional DC small switch that cuts off direct current when the direct current is cut off. In this figure, 301 is a case, 302 is a stationary contact, 303 is a movable contact piece, 304 is a movable contact, 305 is a blocking surface of the case, 305A is a front wall of the blocking surface of the case, 306 is a blocking plate (sliding plate), 307 Is an arc, and the arc flies between the fixed contact 302 and the movable contact 304 in the shortest distance.

  As described above, the normal arc flies between the fixed contact 302 and the movable contact 304 with the shortest distance [see FIG. 8A]. Further, the arc 307 is cut by the shielding plate 306, and the arc path is the shortest distance at that time (see FIGS. 8B to 8C). When the gap between the shielding plate 306 and the shielding surface 305 of the case is 0, the arc 307 searches for a structural gap and flies.

JP 2012-212543 A JP 2013-0777506 A

  However, in the above-described conventional small switch for direct current interruption, there is a problem of how to properly extinguish an arc generated when interrupting direct current, and in that case, the opening / closing durability life is extended. It is desirable to do so.

  In view of the above situation, the present invention provides a DC current interrupting small switch with an arc extinguishing device capable of detouring an arc generated when DC is interrupted in a small switch for interrupting direct current. The purpose is to provide.

In order to achieve the above object, the present invention provides
[1] In a small switch for interrupting DC current with an arc extinguishing device, it is guided to intentionally bypass the arc path that occurs when the switch is turned off, and the arc path is made plural, thereby extending the switching durability life. It is characterized by that.

  [2] In the small switch for interrupting a direct current with the arc extinguishing device according to [1], an arc path is induced by forming a recess in the cut-off surface of the case.

  [3] The small switch for interrupting direct current with the arc extinguishing device according to [1], wherein a plurality of minute protrusions are formed on the contact surface of the movable contact to stabilize the contact and arc path.

  [4] The small switch for interrupting DC current with the arc extinguishing device according to [3], wherein two small protrusions are provided on the contact surface of the movable contact.

  According to the present invention, it is possible to extend the open / close durability life by intentionally detouring the path of the arc generated when the switch is turned off and by making a plurality of arc paths.

  In addition, by providing two minute protrusions on the contact surface of the movable contact, the stability of the contact and the arc path can be achieved.

FIG. 2 is a perspective view showing the inside of a small switch for interrupting a direct current in which a path of an arc is guided by a recess (dent) according to the first embodiment of the present invention. It is a figure which shows the interruption | blocking surface of the case where the arc which shows 1st Example of this invention produced. It is a figure which shows the interruption | blocking surface of the case where the 1st damage groove | channel damaged by the arc which shows 1st Example of this invention produced. It is a figure which shows the interruption | blocking surface of the case where the 2nd damage groove | channel further damaged with the arc which shows 1st Example of this invention produced. It is a figure which shows the interruption | blocking surface of the final case where the 3rd damage groove | channel further damaged by the arc which shows 1st Example of this invention produced. It is a figure which shows the small switch for a direct current interruption which shows the Example of this invention. It is a figure which shows the movable contact of the small switch for a direct current interruption which shows 2nd Example of this invention. It is a perspective view which shows the mode at the time of DC interruption | blocking of the direct current | flow small switch which interrupts | blocks the direct current | flow.

  The small switch for DC current interruption with an arc extinguishing device according to the present invention intentionally bypasses the path of an arc generated when the switch is turned off, and extends the switching durability life by making a plurality of arc paths. I did it.

  Hereinafter, embodiments of the present invention will be described in detail.

FIG. 1 is a perspective view showing the inside of a small switch for cutting off a direct current in which a path of an arc is guided by a recess (dent) according to a first embodiment of the present invention, and FIG. 2 is a first embodiment of the present invention. FIG. 3 is a view showing a cut-off surface of a case in which the arc shown is generated, FIG. 3 is a view showing a cut-off surface of the case in which the first damaged groove damaged by the arc is shown, and FIG. The figure which shows the interruption | blocking surface of the case where the 2nd damage groove | channel further damaged by the arc which shows 1st Example of this was produced, FIG. 5 is the 3rd damage groove | channel further damaged by the arc which shows 1st Example of this invention It is a figure which shows the interruption | blocking surface of the final case where this occurred.
In these drawings, 1 is a case, 2 is a fixed contact, 3 is a blocking surface of the case, 3A is a front wall of the blocking surface of the case, 4 is a recess (dent), and 5 is guided to bypass the recess (dent) 4. Arc path to be played.

  Thus, the small switch for interrupting direct current of the present invention has a switch structure in which the arc is interrupted by the interrupting plate without using a magnet, and the arc is sandwiched between the interrupting plate and the interrupting surface of the case as in FIG. When passing through the gap between the shielding plate and the shielding surface of the case, the arc energy is reduced, and finally the arc is physically broken by the shielding plate. In that case, it is desirable to suppress the burnout of the cut-off surface of the case by the arc as much as possible.

  Therefore, the small switch for interrupting direct current of the present invention induces the arc path generated when the switch is turned off by intentionally bypassing the arc by forming a recess (dent) 4 on the cut-off surface of the case. By configuring a plurality of paths, the opening / closing durability life is extended.

  Note that the longer the travel distance of the shield plate, the more advantageous for arc interception, but the longer the length, the larger the entire switch.

As described above, the small switch for interrupting direct current of the present invention has a structure in which the number of electrical switching durability is increased by taking advantage of the following two arc paths.
(1) The arc searches for a gap and forms a path. That is, an arc whose gap between the shielding plate and the shielding surface of the case is 0 loses its place, and the structural gap becomes the path of the arc.
(2) The arc flies at the shortest distance. That is, the arc flies at the shortest insulation distance (creeping space + space) between the fixed contact and the movable contact.

  As a specific structure, the gap between the shielding plate and the shielding surface of the case is 0, a recess (dent) is provided in a part of the shielding surface of the case, and the arc is recessed by providing a clearance with the shielding plate only in that portion. Guide to pass through. The concave portion (dent) is provided at a position away from the path so that the arc does not fly along the path of the shortest distance as shown in FIG.

  When an arc is generated by opening and closing, the arc flies along a path passing through the recess (dent) 4, but as the number of times of opening and closing increases, a portion corresponding to the arc passing path of the blocking surface 3 of the case is damaged and the first groove 7 </ b> A (induction) Path) is formed. Due to the passage of the arc, damage to the first groove 7A spreads, and the 8A portion of the front wall 3A of the cut-off surface of the case begins to be damaged, and a new gap is formed with the shielding plate. Then, due to the characteristics of the arc that is about to fly at the shortest distance, the arc starts to fly along a path that passes through the damage 8A, and a second groove 7B is formed in this path as the number of times of opening and closing increases. Similarly, the damage to the second groove 7B spreads, and the 8B portion of the front wall 3A of the blocking surface of the case starts to be damaged, creating a new gap with the shielding plate. The arc starts to fly along a path passing through the damage 8B, and finally, a third groove 7C is formed in this path.

  In this way, as the number of times of opening and closing advances, the entire front wall 3A of the case blocking surface is damaged by an arc, and a gap is formed between the blocking plate and the blocking surface 3 of the case. As a result, the arc path changes due to the nature of flying the shortest distance of the arc. As the number of times of opening and closing advances, the arc will fly at the shortest distance.

  As a result, a plurality of arc paths can be formed, and the arc paths are dispersed from the grooves 7A to 7C, thereby extending the opening / closing durability life. In the case where there is only one arc path as in the conventional example of FIG. 8, damage due to arc energy concentrates on the same location of the shielding surface and the shielding plate of the case, and the durability life is shortened.

  Next, a second embodiment of the present invention will be described.

  FIG. 6 is a diagram showing a small switch for interrupting direct current showing an embodiment of the present invention, FIG. 6 (a) is a sectional view thereof, FIG. 6 (b) is a top view of the case, a movable contact 112 and a fixed contact 102 The contact point with is shown. FIG. 6 (c) is an enlarged perspective view of the back surface of the movable contact, FIG. 7 is a diagram showing the movable contact of the small DC current blocking switch according to the second embodiment of the present invention, and FIG. 7 (a) is a sectional view thereof. 7 (b) is a top view of the case and shows a contact point between the movable contact 212 and the fixed contact 202. FIG. FIG. 7C is an enlarged perspective view of the surface of the movable contact.

  In FIG. 6, 102 is a fixed contact, 111 is a movable contact piece, 112 is a movable contact, and 112A is the surface of the movable contact.

  In FIG. 7, 211 is a movable contact piece, 212 is a movable contact, 212A is a surface of the movable contact, 213 is a minute protrusion provided on the surface 212A of the movable contact, and 214 is a fixed contact. When the surface 212A of the movable contact 212 is flat, the contact point between the movable contact 212 and the fixed contact 214 becomes unstable due to variations in parts.

  In addition, if the contact point between the movable contact 212 and the fixed contact 214 is far away from the recess 215, the arc cannot be guided to the cut-off surface recess 215 of the case.

  Therefore, in the present invention, in order to solve this problem, the minute protrusion 213 provided on the front end portion (on the front surface 3A side of the blocking surface) on the surface 212A of the movable contact is formed. Regardless of this, the contact point of the movable contact 212 and the fixed contact 214 is close to the recess 215, and the arc induction to the recess 215 can be stabilized. In addition, the contact resistance value can be stabilized by providing a plurality of minute protrusions 213.

  In the conventional small switch shown in FIG. 10, the number of times of opening and closing is NG (arc can not be cut), whereas in the present invention shown in FIGS. 1 to 5, no abnormality is seen even when the number of times of opening and closing is 10,000. .

  In addition, this invention is not limited to the said Example, Based on the meaning of this invention, a various deformation | transformation is possible and these are not excluded from the scope of the present invention.

  The small switch for DC current interruption with an arc extinguishing device according to the present invention intentionally bypasses the path of an arc generated when the switch is turned off, and extends the switching durability life by making a plurality of arc paths. It can be used as a small switch for interrupting direct current with an arc extinguishing device.

DESCRIPTION OF SYMBOLS 1 Case 2, 102, 214 Fixed contact 3 Case interruption | blocking surface 3A Case interruption | blocking surface front wall 4, 215 Recess (dent)
5 Arc path guided so as to be detoured by recess (dent) 7A First groove 7B Second groove 7C Third groove 8A, 8B Damage 111, 211 Movable contact 112, 212 Movable contact 112A, 212A Movable Contact surface 213 Two minute protrusions on the surface of the movable contact

Claims (4)

  A small switch for DC current interruption with an arc extinguishing device, characterized by intentionally bypassing the arc path generated when the switch is OFF and extending the open / close durability life by making multiple arc paths. .   The small switch for DC current interruption with an arc extinguishing device according to claim 1, wherein the arc path is induced by forming a recess in the interruption surface of the case. .   The small switch for DC current interruption with an arc-extinguishing device according to claim 1, wherein a minute protrusion is formed on the contact surface of the movable contact to stabilize the contact and arc path. Small switch.   The small switch for DC current interruption with an arc-extinguishing device according to claim 3, wherein two small protrusions are provided on the contact surface of the movable contact.

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