JP2013077506A - Small switch for dc current cut-off - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small switch for DC current cut-off in which an opening speed of a movable contact is accelerated, a generated arc is drawn by applying a magnetic field to the arc and further, re-arc caused by ionized gas is prevented effectively.SOLUTION: A small switch for DC current cut-off comprises a shield panel device 19 inserted between a fixed contact 18 and a movable contact 15, and a permanent magnet 21 disposed by the side of the fixed contact 18 and the movable contact 15 such that an arc generated in opening a cable run with the shield panel device 19 is drawn by magnetism.

Description

  The present invention relates to a small switch for interrupting a direct current, and more particularly to a small switch excellent in extinguishing performance of an arc generated when a direct current is interrupted.

FIG. 11 is a perspective view showing a DC current interrupting portion of a conventional DC current interrupting small switch with an arc extinguishing device, FIG. 12 is a plan view of the DC current interrupting portion, and FIG. 13 is a side view of the DC current interrupting portion. FIG.
Conventionally, in a small switch for interrupting DC current with an arc extinguishing device, a permanent magnet 104 is arranged in the vicinity of a DC current interrupting portion 103 in a DC current circuit comprising a fixed contact 101 and a movable contact 102 as shown in FIG. In addition, as shown in FIGS. 12 and 13, the arc 105 generated when the direct current is interrupted is stretched and extinguished by the magnetism of the permanent magnet 104 (see Patent Document 1 below).

JP 9-320375 A

  However, in the above-described small switch for interrupting DC current with an arc extinguishing device, an arc extinguishing device using a permanent magnet is arranged separately from the opening and closing mechanism, and the generated arc is extinguished and flows between the contacts. In order to eliminate the unstable factors of the method of extending and extinguishing the arc by a magnetic field, etc., in which the arc changes depending on the current value and the direction in which the changing arc is extended must be controlled by a magnetic field, a complicated design is required. Necessary, and in some cases, increased size.

  In view of the above situation, the present invention increases the opening speed of the movable contact, extends the arc by applying a magnetic field to the generated arc, and effectively prevents re-arcing due to ionized gas. An object is to provide a small switch.

In order to achieve the above object, the present invention provides
[1] In the small switch for interrupting direct current, the stationary contact is inserted between the stationary contact and the movable contact, and the fixed contact so that the arc generated when the electric circuit is opened by the shielding plate is extended magnetically. And a permanent magnet disposed on the side of the movable contact.

[2] The small switch for direct current interruption according to [1], wherein the interruption plate device includes a spring reversing mechanism that is driven in a horizontal direction at a constant high speed regardless of an operation speed of the operation button, The arc is cut off at the side wall of the plate device and the switch.
[3] In the small switch for interrupting direct current as described in [2] above, the arc extinguishing plate comprising a heat-resistant insulating plate disposed on the side wall of the switch by the shut-off plate device as a residual gas that causes the arc. And is cooled by being pushed into a narrow path in front of the fixed contact leading to the space behind the arc to suppress the recurrence of the arc.

[4] In the small switch for direct current interruption according to [3] above, the space behind the arc-extinguishing plate communicates with the internal space of the switch through a hole formed above the arc-extinguishing plate. And
[5] The small switch for interrupting direct current according to the above [1], wherein the blocking plate device includes a portion guided by a case central recess, a square hole into which a lower end protrusion of a second converter is inserted, and the case On both sides of the portion guided by the central recess, a portion for interrupting the arc, a protrusion for pushing up the movable contact piece, and a tip portion for interrupting the arc are provided.

[6] The small switch for interrupting direct current according to [1], wherein the conductive member has a shape that does not hinder the movement of the movable contact piece and the common terminal between the movable contact piece and the common terminal provided with the receiving portion. It is characterized in that it is directly joined by an auxiliary contact plate made of a thin plate to stabilize the position and operation of the movable contact piece and the common terminal, and to prevent bounce when the contact is closed.
[7] In the small switch for interrupting direct current according to any one of [1] to [6], a part of the base of the contact terminal to which the fixed contact is fixed fits in the narrow path. An extended, grooved, fixed contact wear protection plate is provided.

According to the present invention, the following effects can be achieved.
(1) The opening speed of the movable contact can be increased.
(2) By applying a magnetic field from the side to the arc, the arc can be stably stretched by magnetism.
(3) The arc can be reliably extinguished by using both application of a magnetic field to the arc and mechanical interruption of the arc.

  (4) It is possible to ensure the interruption of the arc and prevent a re-occurring arc due to the disappearance of the residual gas.

It is a top view of the small switch for direct current interruption of the present invention. It is the sectional view on the AA 'line of FIG. FIG. 3 is a sectional view taken along the line BB ′ in FIG. 2 (when the contact is closed). FIG. 3 is a cross-sectional view taken along the line BB ′ in FIG. 2 (when the contact is open). FIG. 3 is a cross-sectional view taken along the line CC ′ of FIG. 2 (when the contact is closed). FIG. 3 is a cross-sectional view taken along the line CC ′ in FIG. 2 (when the contact is open). It is a perspective view of a shield plate device. It is a figure which shows the mode of the arc extinguishing based on FIG. It is a perspective view which shows the narrow path ahead of a fixed contact. It is a perspective view of the fixed contact which shows the protection aspect of a fixed contact. It is a perspective view which shows the interruption | blocking part of the direct current of the conventional small switch for direct current interruption with an arc-extinguishing apparatus. It is a top view of the interruption part of the direct current of the conventional small switch for direct current interruption with an arc-extinguishing apparatus. It is a side view of the interruption part of the direct current of the conventional small switch for direct current interruption with an arc-extinguishing apparatus.

  The small switch for interrupting a direct current of the present invention includes a blocking plate device inserted between a fixed contact and a movable contact, and the fixed contact so that an arc generated when an electric circuit is opened by the blocking plate device is extended magnetically. And a permanent magnet disposed on the side of the movable contact.

Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 is a top view of a small DC current blocking switch according to the present invention, FIG. 2 is a cross-sectional view taken along line AA 'in FIG. 1, and FIG. 3 is a cross-sectional view taken along line BB' in FIG. 4 is a cross-sectional view taken along the line B-B 'in FIG. 2 (when the contact is open), FIG. 5 is a cross-sectional view taken along the line C-C' in FIG. 2 (when the contact is closed), and FIG. FIG. 7 is a perspective view of the shield plate device, FIG. 8 is a view showing the arc extinguishing based on FIG. 6, and FIG. 9 is a perspective view showing a narrow path ahead of the fixed contact. 10 is a perspective view of a fixed contact showing a protection mode of the fixed contact, FIG. 10 (a) is an explanatory view of the fixed contact portion (corresponding to FIGS. 6 and 8), and FIG. 10 (b) is a fixed contact portion. FIG.

  In these drawings, 1 is an operation button, 2 is a housing, 3 is a cover, 4 is a first converter, 5 is a guide, 6 is a base, 7 is a pin, 8 is a connector, 9 is a first coil spring, 10 is a second converter, 11 is a second coil spring, 12 is a sliding rod, 13 is an auxiliary contact plate, 14 is a movable contact piece, and 14A is a protrusion formed on both sides of the movable contact piece 14. The movable contact piece 14 is pushed up by the projection 19D of the blocking plate device 19 to be separated from the fixed contact 18 described later. Reference numeral 15 is a movable contact, 16 is a common terminal, 17 is a contact terminal, 18 is a fixed contact, 19 is a blocking plate device, 19A is a portion guided by a recess in the center of the base, and 19B is inserted into a lower end protrusion of the second converter 10. 19C is a part that cuts off the arc, 19D is a protrusion that pushes up the movable contact piece 14, 19E is a tip part that cuts off the arc, 20 is a heat-resistant insulating arc extinguishing plate, 21 is a permanent magnet, and 22 is a case The floor, 23 is a narrow path, 24 is a hole below the arc-extinguishing plate 20, 25 is a space behind the arc-extinguishing plate 20, 26 is a hole above the arc-extinguishing plate 20, 27 is a space inside the switch, 28 is An arc 31 is a wear protection plate of the fixed contact 18, and 32 is a groove formed in the wear protection plate 31 of the fixed contact 18.

Hereinafter, each part of the small switch for direct current interruption will be described.
First, as shown in FIG. 7, the blocking plate device 19 is formed with a square hole 19 </ b> B into which the lower end protrusion of the second converter 10 is inserted at the center of the portion 19 </ b> A guided by the case center recess. The portions 19C for interrupting the arc are provided on both sides of the portion 19A guided by the recess in the center of the case. A projection 19D that pushes up the movable contact piece 14 and a tip portion 19E that blocks the arc are formed in the portion 19C that blocks the arc.

Next, the arc extinguishing part will be described. As shown in FIGS. 8 and 9, a narrow path 23 is formed on the case floor 22 in front of the fixed contact 18 toward the side wall of the switch. 23 is partitioned by an arc extinguishing plate 20 as a side wall of the switch. The arc extinguishing plate 20 is provided with a lower hole 24, and the hole 24 is connected to a space 25 behind the arc extinguishing plate 20.
Next, a countermeasure for wear of the fixed contact will be described.

  As shown in FIG. 10, a consumable protection plate 31 for the fixed contact 18 is formed by extending a part of the base metal (contact terminal 17) to which the fixed contact 18 is fixed so as to fit in the narrow path 23 in front. A groove 32 is processed in the center. As a result, the portion that becomes the pole of the arc 28 when the contact is opened is moved from the fixed contact 18 to prevent wear. That is, the groove 32 serves as a path for guiding the arc 28 to the tip of the wear protection plate 31.

  Therefore, when the operation button 1 is turned off, the blocking plate device 19 is operated at a high speed by the reversing mechanism regardless of the operation speed of the button 1, and the blocking plate device 19 is moved between the fixed contact 18 and the movable contact 15 at a high speed. The arc 28 is cut off by the shield plate device 19 and the arc extinguishing plate 20 serving as a side wall. At this time, the gas in which the electrode material has evaporated and the gas in which the atmosphere surrounding the arc 28 has been ionized by heat, as shown in FIG. The movable contact piece 14 is operated from a hole 26 above the arc-extinguishing plate 20 serving as a side wall while being cooled in a space 25 behind the arc-extinguishing plate 20 serving as a side wall through a hole 24 formed in the lower part of the arc plate 20. Since it is led to the space 27 inside the wide switch, it is possible to effectively suppress the re-arcing due to the ionized gas.

  As described above, the DC current interrupting small switch according to the present invention increases the breaking speed of the movable contact piece 14, applies a magnetic field to the generated arc 28, stretches the arc, increases the arc voltage, and attenuates the current. In addition, the arc 28 in a damped state is sandwiched between the shield plate 19 and the arc extinguishing plate 20 serving as a side wall to cut off the arc 28, and the gas in which the electrode material has evaporated and the atmosphere surrounding the arc are ionized by heat. The gas was cut off and separated, pushed into the narrow passage 23, and cooled through the space 25 behind the side wall, thereby increasing the dielectric strength and performing sufficient arc extinction.

Hereinafter, the small switch for interrupting direct current of the present invention will be described in more detail.
(1) Speeding up the opening of the movable contact The opening and closing of the movable contact 15 is performed by a blocking plate device 19 that is horizontally operated by a spring reversing mechanism, whereby a high opening speed is obtained irrespective of the operation speed of the operation button 1 of the switch. Can be obtained.

In addition, in order to ensure the contact pressure when the contact is closed, a form in which the force by the second coil spring 11 is applied to the movable contact piece 14 by the sliding rod 12 is also used.
The interior of the switch is divided into three rooms by the guide 5 in parallel with the operation direction, and the center is a room containing a mechanism for driving the blocking plate device 19, and the rooms on both sides of the center are fixed. The room accommodates the contact 18 and the movable contact 15.

In the center room, a second converter 10 in which a first coil spring 9 is installed in the center recess is arranged on the guide 5 with a rotation axis. This axis is arranged at a distance from the axis for rotating the operation button 1.
The first converter 4 is directly fitted to the operation button 1 and performs the same rotational movement with the same rotational axis as a reference. The first converter 4 is fitted with a pin 7 having a spherical tip directly below the center. Therefore, when the operation button 1 is operated, the pin 7 rotates. On the upper side of the first coil spring 9 housed in the second converter 10, a connector 8 having a dent that matches the sphere of the pin 7 is attached and combined with the pin 7 to form a ball joint. .

There is a protrusion having the same diameter as the inner diameter of the first coil spring 9 on the inner side of the recess of the second converter 10, and the first coil spring 9 placed there cannot move horizontally. The upper side opposite to this is a funnel-shaped depression having a large opening in the operation direction of the operation button 1, so that the first coil spring 9 can move in this direction in addition to the compression direction and bend like a bow. Can do.
When the operation button 1 is started to be pressed, the pin 7 starts to compress the first coil spring 9, but the second converter 10 does not rotate. Around the rotation axis, the direction of bending is reversed, and the first coil spring 9 is extended so that it can be flipped along with it. With this force, the second converter 10 rotates. In this way, the second converter 10 performs a constant and high-speed spring reversal operation regardless of the operation speed of the operation button 1.

  At the lower end of the second converter 10, there is a square bar-like protrusion, which is gently inserted into a square hole 19 </ b> B vacated in the center of the blocking plate device 19. The blocking plate device 19 has a “H” shape (see FIG. 7), and the central portion slides horizontally using a concave portion dug in the center of the case as a guide. In this way, the force of the rotational motion caused by the spring reversal operation of the second converter 10 is converted into the horizontal motion of the blocking plate device 19 as it is. Then, the blocking plate device 19 moves constantly in the high-speed horizontal direction toward the pressed side of the operation button 1.

Previously, it was described that the inside of the switch was divided into three rooms by the guide 5, but the guide 5 and the case have a space for allowing the blocking plate device 19 to pass. As one thing, the left and right wings of the “Hi” character extend to each electrical point on both sides.
In this part of the blocking plate device 19, there are two wedge-shaped projections 19D each arranged so as not to interfere with the base width of the movable contact piece 14, and by pushing up the ears that protrude on both sides of the movable contact piece 14, The movable contact 15 is released.

This acts as a force that opens the contact point, and in combination with the above-described movement at high speed, acts as a forced separation for welding.
As shown in FIGS. 5, 6, and 8, the movement of the movable contact piece 14 is a seesaw type that supports the fulcrum portion by receiving, but between the movable contact piece 14 and the common terminal 16 in which the receiving portion is disposed, It is directly joined by a conductive thin plate (auxiliary contact plate) 13 having a shape that does not hinder the movement, so that these positions and operations are stabilized, and bounce countermeasures are taken when the contact is closed.

The joint portion of the auxiliary contact plate 13 is on the side opposite to the contact contact portion of the movable contact piece 14 and in the vicinity of the portion fixed to the base 6 of the common terminal 16, and the movable contact piece 14 and the receiving portion that are in the middle are fitted. Since the area is not joined, it can move freely and freely.
In the first converter 4, the second coil spring 11 and the sliding rod 12 are installed above the movable contact piece 14, and the tip of the sliding rod 12 is in contact with the back of the movable contact piece 14. The force of the second coil spring 11 is transmitted to the movable contact piece 14 while being slid and moved by the rotational movement of the converter 4.

When the contact is closed, as shown in FIG. 5, the sliding rod 12 is positioned between the receiving portion and the contact, and the movable contact piece 14 which is a rigid body reliably applies contact pressure to the fixed contact 18 with the receiving portion as a fulcrum.
When the contact is opened, as shown in FIG. 6, the sliding rod 12 passes through the receiving portion, and the force pressing the movable contact piece 14 is extremely reduced. Shortly before this happens, the barrier plate device 19 begins to lift the movable contact piece 14, so that the contact opens very smoothly and quickly.
(2) Magnetic field application and stable stretching of the arc A wide space in front of the contact is taken, and as shown in FIG. 2, the permanent magnet 21 is placed beside the contact in parallel to the operation direction, and the generated arc 28 Is greatly stretched into the space. As shown in FIG. 2, in the case of two poles, one permanent magnet 21 is arranged for each pole. At this time, the S and N poles of the permanent magnet 21 face each other. By doing so, the lines of magnetic force are easily aligned in parallel, a stable magnetic field can be applied between the contacts, and the direction in which the arc is stretched can be stabilized. The permanent magnet 21 and the contact portions 18 and 15 are separated from each other by the wall of the guide 5, so that the life of the permanent magnet 21 can be extended.
(3) Mechanical interruption As described in (1) above, when the contact button shown in FIG. 6 is opened, when the operation button 1 is operated, the interruption plate device 19 moves horizontally in the contact direction, as shown in FIG. The protrusion 14 </ b> A of the movable contact piece 14 is lifted by the protrusion 19 </ b> D of the blocking plate device 19, and the contact starts to open. As described in the above (2), the arc 28 generated at this time is stretched by applying a magnetic field, and further attenuates by touching the arc extinguishing plate 20 of a heat-resistant insulator installed on the side wall in front of the contact. In order to follow this state, the interrupting plate device 19 interrupts between the movable contact 15 and the fixed contact 18, and the tip end portion 19E that interrupts the arc of the interrupting plate device 19 hits the arc extinguishing plate 20 to cut off the arc 28. As shown in FIG. 9, the case floor 22 in front of the fixed contact 18 is formed with a narrow path 23 that is recessed toward the side wall so as to be covered by the blocking plate device 19, and an arc extinguishing plate as a side wall. A hole 24 formed in 20 is connected to a space 25 behind the hole 24. In the state where the arc 28 is sandwiched and cut off, the breaker plate device 19 blocks the fixed contact 18 and the narrow passage 23 in front, confines the generated high temperature residual gas, and further drives the space 24 behind the side wall from the hole 24. Cool and extinguish.

  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 of the present invention increases the breaking speed of the movable contact, stretches the arc by applying a magnetic field to the generated arc, and effectively prevents recurrence due to ionized gas. It can be used as a small switch.

DESCRIPTION OF SYMBOLS 1 Operation button 2 Housing 3 Cover 4 1st converter 5 Guide 6 Base 7 Pin 8 Connector 9 1st coil spring 10 2nd converter 11 2nd coil spring 12 Sliding rod 13 Auxiliary contact plate 14 Movable contact piece 14A Protrusions formed on both sides of the movable contact piece 15 Movable contact point 16 Common terminal 17 Contact terminal 18 Fixed contact point 19 Blocking plate device 19A Part guided by the case center recess 19B Square hole into which the lower end protrusion of the second converter is inserted 19C A portion for interrupting the arc 19D A protrusion for pushing up the movable contact 19E A tip portion for interrupting the arc 20 A heat-resistant insulator arc extinguishing plate 21 A permanent magnet 22 A case floor 23 A narrow path 24 A hole below the arc extinguishing plate 25 An arc extinguishing Space behind the plate 26 Hole above the arc extinguishing plate 27 Space inside the switch 28 Arc 31 Consumable protection plate for fixed contact 32 Fixed contact Grooves formed in the depletion protective plate

Claims (7)

  A breaker device inserted between the fixed contact and the movable contact, and an arc generated when the electric circuit is opened by the breaker device is extended laterally between the fixed contact and the movable contact. A small switch for interrupting a direct current, characterized by comprising a permanent magnet.   2. The small switch for interrupting direct current according to claim 1, wherein the interrupting plate device includes a spring reversing mechanism that is driven in a horizontal direction at a constant high speed regardless of an operation speed of the operation button, and the interrupting plate device and the switch A small switch for interrupting a direct current, wherein the arc is cut off at a side wall of the switch.   3. A small switch for interrupting a direct current according to claim 2, wherein a residual gas that causes generation of the arc is made to be a space behind an arc-extinguishing plate made of a heat-resistant insulating plate disposed on a side wall of the switch by the interrupting plate device. A small switch for interrupting a direct current, which is cooled by being pushed into a narrow path in front of the fixed contact leading to, thereby suppressing re-arcing of the arc.   4. The small switch for interrupting direct current according to claim 3, wherein the space behind the arc extinguishing plate communicates with an internal space of the switch from a hole formed above the arc extinguishing plate. Small switch for shutoff.   2. The small switch for interrupting a direct current according to claim 1, wherein the blocking plate device is guided to a portion guided by a case center recess, a square hole into which a lower end projection of a second converter is inserted, and guided to the case center recess. A small switch for interrupting direct current, comprising a portion for interrupting the arc, a protrusion for pushing up the movable contact piece, and a tip portion for interrupting the arc on both sides of the portion to be cut.   2. A small switch for interrupting a direct current according to claim 1, wherein the auxiliary contact is made of a conductive thin plate having a shape that does not hinder the movement of the movable contact piece and the common terminal between the movable contact piece and the common terminal provided with the receiving portion. A small direct current cut-off switch characterized in that it is directly joined with a contact plate to stabilize the position and operation of the movable contact piece and the common terminal, and to take measures against bounce when the contact is closed.   The small switch for DC current interruption according to any one of claims 1 to 6, wherein a part of a base metal of a contact terminal to which the fixed contact is fixed is extended to fit in the narrow path, and is provided with a groove. A compact switch for interrupting a direct current, comprising a consumable protective plate for the fixed contact.

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