EP2509091B1

EP2509091B1 - Auxiliary device of circuit breaker

Info

Publication number: EP2509091B1
Application number: EP10834376.5A
Authority: EP
Inventors: Yoshinobu Hamada; Koji Asakawa; Yutaka Sato
Original assignee: Fuji Electric FA Components and Systems Co Ltd
Current assignee: Fuji Electric FA Components and Systems Co Ltd
Priority date: 2009-12-04
Filing date: 2010-11-30
Publication date: 2016-04-13
Anticipated expiration: 2030-11-30
Also published as: CN102576632B; WO2011067922A1; EP2509091A4; KR20120058603A; JP5310513B2; EP2509091A1; TW201126558A; KR101258534B1; JP2011119163A; CN102576632A; TWI390571B

Description

TECHNICAL FIELD

This invention relates to an auxiliary device for a circuit breaker, targeting circuit breakers for wiring applied to low-voltage power distribution equipment and earth leakage circuit breakers, and more specifically relates to the configuration of an undervoltage tripping device and an external operating handle device which are mounted on a circuit breaker and used as auxiliary devices of the circuit breaker.

BACKGROUND ART

As is well known, various auxiliary devices are prepared as options for the circuit breaker of the title; one such device is an undervoltage tripping device.
This undervoltage tripping device trips the circuit breaker when the voltage of a circuit for protection (voltage of the main circuit or control circuit) falls below a voltage stipulated in advance (for example, in the range 35 to 85% of a rated voltage), thereby shutting off the main circuit. As one example, internal type undervoltage tripping devices are known which are inserted into and set inside the case of a circuit breaker for use (see for example Patent Reference 1).
Such an internal type undervoltage tripping device is provided with a tripping mechanism that is mounted on a cassette case within the case of the circuit breaker, and is constituted by an assembly of an electromagnet, an actuator joined to the armature of the electromagnet so as to be opposed to a tripping crossbar of the circuit breaker, an armature release spring, and a reset lever linked to the armature.
Operation and functions of such an undervoltage tripping device are described in detail in Patent Reference 1; the coil of the electromagnet is excited by a current passed by a control circuit with the main circuit of the circuit breaker as its power supply, and attracts the armature of the electromagnet in opposition to the release spring during stationary operation, so as to hold the actuator in the retracted position. On the other hand, when the voltage of the main circuit falls below a stipulated range, the attractive force of the electromagnet is reduced, and restraint of the actuator is removed. As a result, the actuator receives the biasing force of the release spring, strikes the trip crossbar, and causes tripping operation of the circuit breaker.
After tripping operation, when the handle of the circuit breaker is operated from the OFF to the ON position, the reset lever of the undervoltage tripping device linked thereto returns the actuator to the retracted position in opposition to the release spring. In this state, if the main circuit voltage has returned to the stipulated range, the electromagnet attracts and holds the armature, and the actuator is held in the retracted position, so that reclosing of the circuit breaker is established.
As an undervoltage tripping device of a circuit breaker, an undervoltage tripping device with an early closing contact, which combines the above-described tripping mechanism with an early closing contact switch, in which this early closing contact switch is connected to the power supply circuit of the electromagnet coil, is also known (see for example Patent Reference 2).
This undervoltage tripping device with an early closing contact performs circuit breaker closing safely and accurately, and so in the above-described configuration which combines an early closing contact switch mechanism with a tripping mechanism including an electromagnet, in a state of use in which this device is mounted on a circuit breaker, the early closing contact switch mechanism is linked to a driving lever (cam type lever) or similar provided on the handle of the circuit breaker.
When, in the process of handle operation for reclosing after a tripping operation of the circuit breaker, the handle of the circuit breaker, which is halted in the TRIP position, is returned once to the OFF position and then moved toward the ON position, the early closing contact is closed before closing of the main circuit contact of the circuit breaker, and the electromagnetic coil is excited by a current. At this time, if the voltage of the main circuit has returned to a voltage in the stipulated range, the armature of the electromagnet of the tripping mechanism is attracted and held, and the actuator is held in the retracted position, so that when the handle is moved to the ON position, reclosing of the circuit breaker is established. On the other hand, if the main circuit voltage has not returned to a stipulated voltage, the electromagnet armature is not attracted, so that even when the handle is moved to the ON position, the circuit breaker is not reset, and returns to the tripped state.
An undervoltage tripping device with an early closing contact is large in size compared with the internal type undervoltage tripping device disclosed in Patent Reference 1, and without further modification, incorporation within the case of a circuit breaker would be difficult; hence normally a unit case is external mounted on a side face of the circuit breaker case, as in Patent Reference 2, and is linked via a driving lever onto a driving handle, which is a rotary handle of the circuit breaker onto which the early closing contact switch mechanism is mounted.
On the other hand, the above-described circuit breakers (circuit breakers for wiring, earth leakage circuit breakers) are generally installed on and used in wiring boards, distribution boards, and similar, and as auxiliary devices, externally operated handle devices which perform operations to open and close the circuit breaker from the front of the panel door are used. As one such example, a design is known in which a rocker handle of the circuit breaker is driven to the ON, OFF and RESET positions by operation of the rotary handle mounted on an external operating handle device (see for example Patent Reference 3).
Next, the structure of a conventional example of an external operating handle device is explained using Fig. 8. In Figs. 8(a) to 8(c), 1 is a circuit breaker (wiring circuit breaker), and 2 is an external operating handle device, mounted on the case of the circuit breaker as an auxiliary device of the circuit breaker 1. Here, the circuit breaker 1 is configured comprising, installed in a case 1a, an open/close mechanism 1b, movable contact point 1c, open/close mechanism 1d comprising a reversal operation type toggling mechanism, rocker handle 1e disposed on the top of the case 1a and linked to the open/close mechanism 1d, and overcurrent tripping device 1f, and similar. 5a is a nameplate displaying the positions ON, OFF, TRIP, RESET of the handle 4.
The open/close operation of the above circuit breaker 1 is well known; when the rocker handle 1e is switched by moving from the ON position as shown to the right and downward to the OFF position, in the midst of this stroke the open/close mechanism 1d performs a reversal operation, receiving the biasing force of the open/close spring of the open/close mechanism 1d to open the movable contact point 1c. Further, when a main circuit overcurrent is detected and the overcurrent tripping device 1f operates, the open/close mechanism 1d performs a release operation, the movable contact point 1c is opened, and the main circuit current is cut off. Through this tripping operation, the rocker handle 1e moves to a position intermediate between the ON position and the OFF position, and displays the trip operation state.
On the other hand, the external operating handle device 2 comprises, mounted on a base 3 fixed in place by fastening with screws to the top of the case 1a of the circuit breaker 1, a rotary handle 4, handle cover 5, sliding base 6 and other driving components; a turning base 4b linked to a support shaft 4a of the handle 4 comprises a crank pin 4c. The sliding base 6 is slidably guided and supported in a direction parallel to the rocker handle 1e of the circuit breaker 1, and a long hole 6a directed perpendicular to the sliding direction is opened in the plate face thereof; the crank pin 4c is mated with this long hole 6a and linked with the rotary handle 4. Further, in a state in which the external operating handle device 2 is mounted on the circuit breaker 1, the sliding base 6 comprises a pusher 6b which opposes, from the ON side, the knob of the rocker handle 1e protruding from the case 1a of the circuit breaker 1, and a biasing spring 6c which presses the pusher 6b from behind toward the knob of the handle 1e.
In the above configuration, when the rotary handle 4 is rotated in manual operation from the ON position to the OFF position, the sliding base 6 slides rightward via the crank pin 4c, and the rocker handle 1e of the circuit breaker 1 is driven toward the OFF position via the pusher 6b. Here, when the handle 1e is displaced to substantially the intermediate position of the movement stroke, the toggling mechanism of the open/close mechanism 1d provided in the circuit breaker 1 performs reversal operation. By this means, the movable contact point 1 c recedes from the fixed contact point 1 b and moves to the open position, and the circuit breaker 1 is turned OFF.
Further, when the circuit breaker 1 detects and overcurrent and performs tripping operation, the handle 4 of the external operating handle device 2 linked to the rocker handle 1e moves to the TRIP position intermediate between the ON position and the OFF position, and halts. And, in order to reclose the circuit breaker 1 from this state, first the rotary handle 4 is turned to the RESET position. By this means, the tripping mechanism linked to the open/close mechanism 1d of the circuit breaker 1 is reset, and then when the rotary handle 4 reversed and turned to the ON position, the rocker handle 1 e of the circuit breaker 1 moves to the OFF position, and the movable contact point 1 c makes contact with the fixed contact point 1 b, establishing reclosing of the circuit breaker 1.

Patent Reference 1: Japanese Patent Application Laid-open No. H10-255639
Patent Reference 2: Patent Publication No. 3867541
Patent Reference 3: Japanese Patent Application Laid-open No. 2007-134148 (Fig. 7 and Fig. 8)
Patent Reference 4: United States Patent Application US 2002/158733 A1
Patent Reference 5: French Patent Application FR 2831321 A1
Patent Reference 6: European Patent Application EP 1261010 A1

Patent Reference 4 discloses an under-voltage tripping device installed on a main body of a circuit breaker including an electromagnetic under-voltage tripping mechanism, an early-operation auxiliary switch for switching a conductive path of an electromagnet of the electromagnetic under-voltage tripping mechanism in connection with a handle mechanism of the circuit breaker, and a unit case having two opposite ends and external connection terminals at the two opposite ends.
Patent Reference 5 discloses a circuit breaker and an auxiliary device including an undervoltage tripping mechanism and an early closing contact mechanism. Both mechanism are coupled to each other.
Patent Reference 6 teaches an auxiliary device for a circuit breaker, comprising an electrical protection unit that cooperates, by means of a mechanism, with an opening slider biased by a return spring. In case of a voltage drop, the opening slider is released acting on a safety release lever of an enclosed circuit breaker.
However, the above-described conventional undervoltage tripping devices and external operating handle devices prepared by manufacturers as auxiliary devices for circuit breakers have the following problems in accommodating optional specifications specified by users.
That is, various auxiliary devices prepared by manufacturers as options for the above-described circuit breakers are adopted to accommodate the specifications of users. In such cases, optional undervoltage tripping device products include, as described above, normal internal type undervoltage tripping devices not provided with an early closing contact (see Patent Reference 1), and undervoltage tripping devices with an early closing contact (see Patent Reference 2); these specifications further differ according to the type, rated voltage, and other parameters of the circuit breaker. In addition, there are also cases in which a circuit breaker is combined for use with an external operating handle device, and in these and other ways, auxiliary device types vary according to the environment of use of the circuit breaker, user specifications, and similar.
Hence circuit breaker manufacturers must prepare various types of undervoltage tripping devices with different specifications and designs in anticipation of options specified by users, and costs are entailed in stocking and managing such optional products.
However, when adopting the above-described undervoltage tripping device with an early closing contact (see Patent Reference 2) as an auxiliary device for a circuit breaker, it is necessary to equip the circuit breaker in advance with a dedicated rotary handle provided with a driving lever which is linked to the early closing contact switch mechanism.
However, in an ordinary circuit breaker (see Fig. 8) a rocker handle is not provided as standard, and when adopting an undervoltage tripping device with an early closing contact, various circuit breakers provided with dedicated rotary handles must be used. If the above-described dedicated rotary handle is provided as standard in a circuit breaker in advance, in anticipation of accommodating an undervoltage tripping device with an early closing contact, there is the problem that in cases where an undervoltage tripping device with an early closing contact is not used, specifications are excessive, and the cost of the circuit breaker product is increased.

DISCLOSURE OF THE INVENTION

This invention was devised in light of the above problems, and has as an object the provision of an auxiliary device for a circuit breaker wherein, with respect to an undervoltage tripping device applied to a circuit breaker, optional products related to the undervoltage tripping device can be divided into a plurality of units and configured in advance, and units selected according to option specifications specified by a user can be combined and used with a circuit breaker, to enable accommodation of specifications with various options specified by simple means.
In order to attain the above object, an auxiliary device of a circuit breaker according to one embodiment of the invention is an auxiliary device of a circuit breaker which has, as the auxiliary device, an external operating handle device and an undervoltage tripping device, wherein the undervoltage tripping device is divided into two modules, which are a tripping unit comprising a tripping mechanism and an early closing contact unit comprising an early closing contact; the tripping unit is internally provided in a case of the circuit breaker, the early closing contact unit is externally provided on the external operating handle device such that the early closing contact is linked to an internal mechanism of the external operating handle device, and the early closing contact is closed midway during ON operation of the external operating handle device and before a main circuit contact of the circuit breaker closes.
Further, the auxiliary device of a circuit breaker according to one embodiment of the invention is the external operating handle device, comprising a base mounted on the case of the circuit breaker; a rotary type handle; a sliding base which converts rotation of the handle into linear motion and drives a rocker type handle of the circuit breaker in ON and OFF directions; a pusher, installed on the sliding base and opposed to the rocker type handle from the ON operation direction; and a spring which biases the pusher from the rear, the external operating handle device being configured with a backlash stroke set between the sliding base and the pusher, and the movement of the sliding base corresponding to the backlash stroke is captured, and the early closing contact of the early closing contact unit is caused to perform open/close operation, in the process of turning on the circuit breaker.
Further, in the auxiliary device of a circuit breaker according to one embodiment of the invention, the early closing contact unit comprises an assembly of a limit switch provided with the early closing contact, and a frame with a terminal which holds the limit switch; the frame is detachably mounted on a base of the external operating handle device, and an operation end of the limit switch is linked to the sliding base of the external operating handle device at this mounted position.
By means of an auxiliary device of a circuit breaker of this invention, by configuring an undervoltage tripping device as described above as an auxiliary device of a circuit breaker, the minimum number of types of optional products can be selected appropriately and applied to the circuit breaker, so that various specified option specifications can be accommodated by simple means.
That is, when a normal undervoltage tripping device not having an early closing contact function is applied as an auxiliary device of a circuit breaker, immediate accommodation is possible by providing the tripping unit internally in the case of the circuit breaker. Further, in this case an external operating handle device can be mounted on the circuit breaker as necessary.
On the other hand, as an undervoltage tripping device, when the option specifications are changed to include an early closing contact function, the above-described existing tripping unit is internally provided without modification in the case of the circuit breaker, and an early closing contact unit can be added as an optional product, externally mounted on the external operating handle device mounted on the circuit breaker, to accommodate specifications by simple means. Hence circuit breaker manufacturers may prepare a smaller number of optional products than in the prior art, and the costs entailed in stocking and managing such optional products can be greatly reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is an exploded perspective view of an example of this invention, in which the auxiliary devices of an external operating handle device and an undervoltage tripping device are mounted on a circuit breaker;
Fig. 2 shows the configuration of an undervoltage tripping device with an early closing contact applied to the circuit breaker of Fig. 1, in which Figs. 2(a) and 2(b) are perspective views of the tripping unit and the early closing contact unit respectively;
Fig. 3 shows the assembled structure of the external operating handle device in Fig. 1, in which Fig. 3(a) is an exploded perspective view of the entire device, and Fig. 3(b) is an exploded perspective view of the sliding base in Fig. 3(a);
Fig. 4 shows states of operation of the external operating handle device shown in Fig. 3, wherein Figs. 4(a) and 4(b) respectively show the states of rotating the handle to the ON and OFF positions;
Fig. 5 is an external perspective view of the state of use when the early closing contact unit of Fig. 2 is externally mounted onto the external operating handle device of Fig. 3, which is mounted on the circuit breaker;
Fig. 6 is an external perspective view of a state of use with the early closing contact unit removed in Fig. 5;
Fig. 7 explains handle operation in a state of use of the early closing contact unit of Fig. 5, in which Figs. 7(a) to 7(d) show transitions in the handle position when rotating the handle of the external operating handle device from the OFF position to the ON position, and Figs. 7(e) to 7(h) show transitions in the operation of the sliding base, pusher, circuit breaker rocker handle and early closing contact unit corresponding to Figs. 7(a) to 7(d) respectively; and
Fig. 8 shows the structure of the state of use with a conventional external operating handle device mounted on a circuit breaker, in which Fig. 8(a) is a side cross-sectional view, Fig. 8(b) is a plane view, and Fig. 8(c) is a perspective view showing the internal mechanism of the external operating handle device.

BEST MODE FOR CARRYING OUT THE INVENTION

Below, embodiments of the invention are explained based on Fig. 1 to Fig. 7. In the embodiments, members corresponding to members in Fig. 8 are assigned the same symbols, and explanations are omitted.
First, Fig. 1 shows an example of this invention, which is an external operating handle device and undervoltage tripping device mounted as auxiliary devices on a circuit breaker. In the figure, 1 is the circuit breaker comprising a rocker handle 1e on the top of a case 1a, 2 is the external operating handle device, 7 is a tripping unit of the undervoltage tripping device, internally provided in the case 1a of the circuit breaker 1, and 8 is an early closing contact unit of the undervoltage tripping device, detachably mounted externally on the rear-face side of the base 3 of the external operating handle device 2, disposed between [the base 3 and] the circuit breaker 1.
Here, the tripping unit 7 is configured with a tripping mechanism, including an electromagnet, mounted on a cassette-type unit case as shown in Fig. 2(a), similarly to that of Patent Reference 1 described above. 7a is an actuator opposed to a trip crossbar of the circuit breaker, protruding from the unit case, and 7b is a reset lever. On the other hand, as shown in Fig. 2(b), the early closing contact unit 8 comprises an assembly of a limit switch 8a provided with an early closing contact, and a mounting frame 8b which holds the limit switch 8a; the mounting frame 8b comprises an external connection terminal 8c, terminal screws 8d, and a pair of support legs (snap fits) 8e protruding upward from both ends of the mounting frame 8b.
Further, the external operating handle device 2 has substantially the same configuration as the conventional external operating handle device shown in Fig. 8; the detailed structure thereof is shown in Fig. 3. That is, the sliding base 6 mounted on the base 3 of the external operating handle device, guided in a straight line and supported, has a pin 6d erected on the upper-face side thereof which mates with a groove 4b-1 in the turning base 4b, and is linked to the rotary handle 4 via a support shaft 4a. Further, a window hole 6e, with the shape of a small square placed on a large lateral rectangle, is cut out and opened in the plate face of the sliding base 6, and as explained below, a pusher 6b, opposed from the ON side by the rocker handle 1e (see Fig. 1) of the circuit breaker 1, set with a backlash stroke with the sliding base 6, and a weak spring (coil spring) 6c which biases the pusher 6b from behind, are set in this window hole 6e. Further, a cam groove 6f which functions as a dog opening and closing the limit switch 8a (see Fig. 2(b)) of the above-described early closing contact unit 8 is formed in a side face of the sliding base 6 along the direction of movement.
Figs. 4(a) and 4(b) show the assembled state of the external operating handle device 2; when the rotary handle 4 is rotated manually to the ON and OFF positions, the sliding base 6, linked to the handle 4, slides and moves in a straight-line direction, and as shown in Fig. 8, drives the rocker handle 1e of the circuit breaker 1 to the ON and OFF positions.
Further, Fig. 5 shows the state of use in which the early closing contact unit 8 of the undervoltage tripping device is additionally mounted on the external operating handle device 2, mounted on the circuit breaker 1 (although not shown, the tripping unit 7 of the above-described undervoltage tripping device is internally set in the case of the circuit breaker). Here, the early closing contact unit 8 is snap-fit and detachably joined by pressing, from the rear-face side, the support legs 8e provided in the frame 8b into engaging holes 3e (see Fig. 1) opened in the base 3 of the external operating handle device 2. Further, in this assembled state, the terminals 8c of the early closing contact unit 8 are connected to the exciting circuit of the electromagnet coil incorporated in the tripping unit 7. On the other hand, Fig. 6 shows the state of use in which an early closing contact unit 8 is not used, and the tripping unit 7 is internally set in the case of the circuit breaker 1.
That is, by employing a configuration in which the undervoltage tripping device is divided into two optional parts, which are the tripping unit 7 and the early closing contact unit 8, cases where an undervoltage tripping device without an early closing contact function is applied as an option can immediately be accommodated by inserting, setting and using the tripping unit 7 in the case 1a of the circuit breaker 1, as in Fig. 6.
Further, in cases where this undervoltage tripping device is to be provided with an early closing contact function, by adding the early closing contact unit 8 and mounting on the external operating handle device 2 as in Fig. 5, optional specifications for an undervoltage tripping device with an early closing contact can be accommodated by simple means.
Next, in a state of use in which the early closing contact unit 8 is mounted on the external operating handle device 2, Fig. 7 is used to explain transitions in operation of the early closing contact corresponding to handle operation.
First, Figs. 7(a) and 7(e) show a state in which the rotary handle 4 of the external operating handle device 2 is halted in the OFF position. In this state, the sliding base 6 is halted on the left end of the movement stroke by the biasing force of a return spring 9 (tension coil spring), and in this position a backlash stroke L1 is held between the rear end of the pusher 6b, being biased by the spring 6c, and the rear end of the window hole 6e opened in the sliding base 6. Further, in this position the limit switch 8a of the early closing contact unit 8 disposed on a side face of the sliding base 6 is opposed to the cam groove 6f of the sliding base 6, and the early closing contact is OFF.
When, from this state, rotation of the rotary handle 4 toward the ON position is begun (see Fig. 7(b)), the sliding base 6, driven by this rotation, begins to move rightward. In this case, in the stroke range immediately after the start of motion corresponding to the above-described backlash stroke L1 (see Fig. 7(e)), the pusher 6b biased from behind by the weak spring 6c abuts the rocker handle 1e of the circuit breaker, but the rocker handle 1e remains halted in the OFF position, the limit switch 8a escapes from the cam groove 6f of the sliding base 6, and the early closing contact is closed (ON operation). By this means, the coil of the electromagnet incorporated in the tripping unit 7 (see Fig. 2(a)) of the undervoltage tripping device is excited by a current.
And, when rotation of the rotary handle 4 is continued from the position of Fig. 7(b) toward the ON position, the sliding base 6 presses the rocker handle 1e of the circuit breaker which is integral with the pusher 6b, and midway in this movement stroke, the toggling mechanism (see Fig. 8) of the open/close mechanism 1d of the circuit breaker rapidly performs a reversal operation. By this means, the main circuit contact receives the biasing force of the open/close spring of the toggling mechanism and closes, and at the same time the rocker handle 1e reaches the stroke end shown in Fig. 7(e), and halts at this ON position. The operation stroke of the rocker handle 1e accompanying this closing operation of the main circuit contact is indicated by L2 in the figure.
Further, when the rocker handle 1e of the circuit breaker reaches the ON position, the rotary handle 4 of the external operating handle device 2 passes the ON position somewhat, as shown in Fig. 7(c), and after this overrun halts at the ON position of Fig. 7(d). Further, accompanying this operation of the rotary handle 4, the sliding base 6 and pusher 8b pass through Fig. 7(g) to halt at the position of Fig. 7(h). The limit switch 8a of the early closing contact unit 8 holds the ON state even after the main circuit contact of the circuit breaker has closed, and maintains an excitation current in the electromagnet coil incorporated in the tripping unit 7 (see Fig. 2(a)).
As is clear from the above explanation, the undervoltage tripping device of this embodiment combines a tripping unit 7 and an early closing contact unit 8, and so can exhibit the same operations and functions as the undervoltage tripping device with an early closing contact described in Patent Reference 2. Moreover, there is no need to install a dedicated rotary handle in the circuit breaker which links to the early closing contact, as described in Patent Reference 2, and merely by somewhat modifying the sliding base of the external operating handle device and additionally external mounting the above early closing contact unit 8 on this external operating handle device, an existing internal type undervoltage tripping device (see Patent Reference 1) can be used as-is, and optional specifications for an undervoltage tripping device with an early closing contact function can be accommodated by simple means. By this means, circuit breaker manufacturers can reduce the number of optional products prepared as auxiliary devices for undervoltage tripping devices compared with previously, and costs entailed in stocking and management of such products can be reduced.

INDUSTRIAL APPLICABILITY

As described above, in an auxiliary device of a circuit breaker of this invention, an optional product related to an undervoltage tripping device is divided into a plurality of units and configured in advance, and units selected according to option specifications specified by a user can be combined and used with a circuit breaker, to enable accommodation of specifications with various options specified by simple means.

EXPLANATION OF REFERENCE NUMERALS

1: Circuit breaker
1a: Circuit breaker case
1e: Rocker handle
2: External operating handle device
3: Base
4: Rotary handle
6: Sliding base
6b: Pusher
6c: Spring
6f: Cam groove
7: Tripping unit
8: Early closing contact unit
8a: Limit switch
8b: Frame
8e: Support leg

Claims

An auxiliary device for a circuit breaker (1), which auxiliary device comprises an external operating handle device (2) and an undervoltage tripping device,
the undervoltage tripping device is divided into two modules, which are a tripping unit (7) comprising a tripping mechanism and
an early closing contact unit (8) comprising an early closing contact,
characterized in that;
the tripping unit (7) is adapted to be internally provided in a case (1a) of the circuit breaker (1),
the early closing contact unit (8) is externally provided on the external operating handle device (2) such that the early closing contact is linked to an internal mechanism of the external operating handle device (2), and
the early closing contact is closed midway during ON operation of the external operating handle device (2) and before a main circuit contact of the circuit breaker (1) closes.
The auxiliary device for a circuit breaker (1) according to Claim 1,
characterized in that the external operating handle device (2) comprises
a base (3) mounted on the case (1a) of the circuit breaker (1);
a rotary type handle (4);
a sliding base (6) which converts rotation of the handle (4) into linear motion and drives a rocker type handle (1e) of the circuit breaker (1) in ON and OFF directions;
a pusher (6b) installed on the sliding base (6) and opposed to the rocker type handle (1e) from the ON operation direction; and
a spring (6c) which biases the pusher (6b) from the rear, the external operating handle device (2) being configured with a backlash stroke set between the sliding base (6) and the pusher (6b), and
the movement of the sliding base (6) corresponding to the backlash stroke is captured and the early closing contact of the early closing contact unit (8) is caused to perform open/close operation, in the process of turning on the circuit breaker (1).
The auxiliary device for a circuit breaker (1) according to Claims 1 or 2, characterized in that the early closing contact unit (8) comprises
an assembly of a limit switch (8a) provided with the early closing contact, and
a frame (8b) with a terminal which holds the limit switch (8a), and
the frame (8b) is detachably mounted on a base (3) of the external operating handle device (2), and an operation end of the limit switch (8a) is linked to the sliding base (6) of the external operating handle device (2) at this mounted position.