JPS6138567B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to circuit breakers.

When re-closing a circuit breaker that was opened due to overcurrent or opened during a power outage, it must be closed while the switch in the branch circuit connected to the circuit breaker remains closed. If this occurs, a motor or the like connected to the branch circuit will start operating at the same time as the circuit breaker is closed, and there is a risk that an unexpected accident may occur to an operator who is not expecting this.

In view of these points, the present invention includes a switch and its opening/closing mechanism suitable for configuring a protection circuit that allows closing of a circuit breaker only when a branch circuit switch is open. The purpose is to provide a circuit breaker.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

FIG. 1 is a circuit diagram showing the wiring state of a circuit breaker 10 according to the present invention and branch switches 12, 14, and 16 connected to the circuit breaker.

As shown in the figure, the circuit breaker 10, like a normal circuit breaker, senses the undervoltage of the switching section 18 and the bus bar 20 to which the switching section is connected, and opens (releases) the switching section 18. The present invention is characterized in that it includes a release device 22 and switches 24 and 26 connected in parallel to the release device 22, respectively. The switches 24 and 26 are the opening/closing portion 18
The switch 24 is linked to the opening/closing operation of the opening/closing section, and is opened when the opening/closing section is opened and closed when the opening/closing section is closed. The section 18 and the switch 26 are closed in this order.

Branch switches 12, 14, 16 are circuit breakers 10
are connected in parallel. As shown in the figure, the branch switches 12, 14, 16 are normally closed auxiliary switches 36, 38, 4 that are opened and closed in conjunction with the respective opening and closing operations.
0, and each switch is configured to close only when its respective switch is open. As shown, these switches are switch 24
connected in series.

In normal use, circuit breaker 10 is closed and branch switches 12, 14, 16 are closed. Therefore, in this state, the undervoltage release device 22
switch 24 and auxiliary switch 3 connected to
6, 38, and 40 are opened, but since the switch 26 is closed, a reference voltage is applied to the release device 22 by the circuit including the switch, and the opening/closing part 18 of the circuit breaker 10 is kept closed. be done. However, when the main circuit voltage decreases, the undervoltage release device operates to open the switching section 18. Along with this, switches 24 and 26 are also opened.

Therefore, when closing the circuit breaker 10 again, first the branch switches 12, 14,
16 (therefore, this opens the auxiliary switch 3
6, 38, 40 are closed). When the circuit breaker 10 is closed in this state, the switch 24 is closed before the opening/closing part 18 and the switch 26 are closed as described above, and the undervoltage release device 22 and the auxiliary switches 36, 38, 40 are closed. The circuit is closed and a reference voltage is applied to the release device, thereby
The opening/closing part 18, which is subsequently closed, is kept closed.

However, even if the circuit breaker 10 is closed while the branch switches 12, 14, and 16 are closed, the circuit will not close even if the switch 24 is closed because the auxiliary switches 36, 38, and 40 are open. Since the reference voltage is not applied to the undervoltage release device 22 and the release device performs the release (opening) operation of the opening/closing portion 18, the opening/closing portion 18 cannot be closed.

When the opening/closing section 18 is closed as described above, the switch 26 is also closed, so even if the branch switches 12, 14, 16 are closed and the auxiliary switches 36, 38, 40 are opened afterwards, the switch 26 is closed. A reference voltage is applied to the undervoltage release device 22 via the switch 26, so that the opening/closing section 18 is maintained in the closed state.

Although not shown in FIG. 1, the circuit breaker 10 described above includes an input terminal and an output terminal to which the input side and output side of the switching section 18 are connected, and the switch 2.
The bus bar 20, branch switches 12, 14, 16, auxiliary switches 36, 38, 40, etc. are connected via these input and output terminals. It is clear that it is connected to

FIG. 2 shows a circuit breaker 5 which embodies the basic structure of the circuit breaker 10 according to the present invention described above.
A perspective view of the main parts of 0 is shown, and FIGS.
The figure shows a cross-sectional view of the main parts of the circuit breaker.

As illustrated, this circuit breaker 50 includes a base 52;
From side walls 54, 54, etc. installed at intervals on the base and partitioning the inside of the circuit breaker into three chambers, and a cover 56 set on the side walls (see FIGS. 3 to 5). It has an insulating box body with side walls 5
In each room partitioned by 4, 54, opening/closing parts 58, 58, 58 are installed, respectively, to constitute a three-pole circuit breaker.

As is clear from FIGS. 3 to 5, each opening/closing section 58 has a fixed contact 60 fixed to the base 52 and a movable contact 62 that comes into contact with and separates from the fixed contact. It is attached to a holder 65 that rotates around a pivot 64 attached to the side wall 54. The holder includes a rotating base 66 that is pivotally attached to a pivot 64, and a support that supports the movable contact 62 and is pivotally attached to a pivot 70 extending between side walls 68, 68 depending from both sides of the base. 72.

3 to 5 particularly show the opening/closing section provided in the central chamber among the opening/closing sections 58 of the three chambers shown in FIG. 2. This central opening/closing section 58 is provided with a mechanism 7 for opening/closing the opening/closing operation.

To explain this mechanism 7, first, the opening/closing part 58
A pivot 73 is provided in the side wall 54 in an upper position, to which a latch 74 is pivotally attached and which connects an upper link 76 and a lower link 78.
It is connected to the holder 65 of the opening/closing part 58 by a link mechanism 79 consisting of. Furthermore, at the upper position, there is an opening 8 provided in the cover 56 of the circuit breaker.
A substantially inverted T-shaped operating lever 82 is provided extending outward through the 0, and a substantially inverted U-shaped yoke 84 (see particularly FIG. 2) is provided on the lower end surface of the lever. The lower ends of the legs 86, 86 provided at intervals in the width direction of the yoke are bifurcated, and the side walls 54, 5 defining the central chamber are bifurcated.
The control lever 82 is placed on pins 88, 88 protruding from the inner surface of the control lever 82, so that the operating lever 82 can rotate around the pins. The right end of the top wall 90 (FIGS. 3-5) between the legs 86, 86 of the yoke 84 is bent downwardly so as to be engageable with the latch 74. As clearly shown in FIGS. 2 and 3, a compression spring 96 is stretched between the top wall 90 of the yoke 84 and a pivot 94 connecting the upper and lower links 76, 78 of the link mechanism 79. . In the figure, 98
is a general-purpose trip device for engaging and unlatching a latch.

Here, to explain the operation of the above opening/closing operation mechanism 7, when the circuit breaker 50 is in the open (cut off) state, the latch 74 is released from the locking pawl 100 of the tripping device 98 as shown in FIG. The tension of the compression spring 96 acting on the central pivot 94 of the linkage 79 bends the linkage 79 into a dogleg shape and pulls it upwards, thus releasing the latch 74 with which it is articulated. The movable contact 6 is rotated clockwise about its pivot 73 and is similarly connected to a link mechanism 79.
The movable contactor 62 is separated from the fixed contactor 60 by rotating the second holder 65 counterclockwise about its pivot 64. To change this state to a closed (conducting) state as shown in FIG. 5, first open the opening 8 of the cover 56 in the open state as shown in FIG.
0, move the lever 82 at the approximately central position to the fourth position.
The latch 74 is rotated counterclockwise about its pivot 88 and tilted to the left as shown, and the latch 74 is rotated counterclockwise about its pivot 73 to release the release device 98.
It engages with the stop pawl 100 of. Next, by rotating the lever 82 clockwise about the pivot 88, the upper end locking portion 96' of the compression spring 96 is placed on the line connecting the central pivot 94 of the link mechanism 97 and the upper pivot 104 (see FIG. 3). When moving to the right from the position (hereinafter referred to as the dead center), the spring force acts to move the central pivot 94 of the link mechanism to the right, so that the link mechanism is extended almost in a straight line. Therefore, the holder 65 is rotated clockwise around the pivot 64 to bring the movable contact 62 into contact with the fixed contact 60. The spring 108 interposed between the rotating base 68 and the support part 72 of the holder 65 biases the movable contact 62 toward the fixed contact 60 in the electrically conductive state shown in FIG. , to ensure that both contacts are in contact. In addition, as shown in FIGS. 2 to 5, the movable contacts 6 in the three opening/closing parts 58
A cross bar 109 is fixed across the holder 65 that supports 2, and when the central opening/closing part 58 is opened/closed, the other two opening/closing parts are also opened/closed.

The circuit breaker 50 according to the present invention is further provided with a switch mechanism 110 corresponding to the switches 24 and 26 in FIG. This switch mechanism will be explained below.

In the embodiment shown in FIG. 2, this switch mechanism is mainly provided on the right opening/closing part 58. That is, in FIG. 2, 112 and 114 are microswitches, each connected in parallel to an undervoltage release device (not shown in the embodiments shown in FIGS. 2 to 5) as shown in FIG. This corresponds to the switches 24 and 26 in FIG. These microswitches are mounted at a predetermined distance on two mounting bars 120, 120 extending horizontally above the opening/closing section 58 from a mounting plate 118 fixed to the base 52 of the circuit breaker. As shown in FIGS. 2, 4, and 5, one end of a substantially inverted L-shaped elastic actuator 126 is fixed to one side of the switch 112 so as to surround the switch 112. The button 130 of the switch is operated by the deflection of the actuator. (See Figures 4 and 5). To perform this actuator deflection operation, the mounting plate 118 of the switches 112, 114 is used in the illustrated embodiment.
A rotating member 134 is provided which is rotatable around a pivot shaft 132 fixed to the actuator 126, and the member 134 can be engaged with a bent portion 136 at one end of the actuator 126.
38 is fixed, and the upper half of the yoke 8 is bent at a right angle and the tip is fixed to the operating handle 82.
The rotary member 134 is inserted into and engaged with an opening 137 provided in one of the leg portions 86 of 4, so that the rotary member 134 rotates around the pivot shaft 132 as the operating lever 82 is rotated, and the actuator 126 is rotated as appropriate. The user has to operate the switch button 130 very quickly.

In the actuator 126, when the circuit breaker is closed as described above, the operating lever 82 is rotated clockwise from the state shown in FIG. Before reaching the position on the line connecting the center and upper pivots 94 and 104, that is, to the right of the dead center, and extending the link mechanism (therefore, the opening/closing part is turned ON), the engagement with the switch button 130 is disengaged and the corresponding The switch 112 is turned on.

FIG. 6 shows the above relationship (in solid lines). Note that the stroke indicated by the broken line indicates the case where the circuit breaker 50 in the state shown in FIG. 5 is opened by rotating the operating lever 82 counterclockwise around its pivot shaft 88. It can be seen that first the micro switch 112 is turned off, and then the opening/closing section is turned off.

Micro switch 114 is micro switch 1
It is the same type as 12 and is installed upside down. Actuator 140 of the switch 114
is formed by bending a long and thin elastic member into a dogleg shape,
Its one end is fixed to one end of the lower surface of the micro switch, and the lower half 140' is bent.
is capable of engaging with the upper surface of the holder 65 of the movable contact in the opening/closing portion 58 . As shown in FIG. 2, when the circuit breaker is in the open and shut off state, the holder
5 presses the lower half 140', causing the actuator to bend upward, thereby pressing a switch button (not shown) provided on the bottom surface of the micro switch 114, which is in the OFF state. When the circuit breaker is closed and the holder 65 is in the position shown in FIG.
The switch button is no longer pressed and the switch is in the ON state.

When using the circuit breaker 50 with the above configuration, the input side terminal is connected to the bus bar, the output side terminal is connected to the branch circuit line, and the circuit breaker 50 shown in FIG. The contacts 36, 38, 40 are connected in series to the micro switch 112, and the micro switch 114 is connected to the contacts 36, 38, 40 in series.
It is connected to the same ground wire as the circuit including 40 to form a circuit as shown in FIG.

When an overcurrent flows through the circuit breaker 50, the undervoltage release device activates and releases the latch 74 from the tripping device 98.
is removed and the above-mentioned interruption occurs. In addition, when closing this circuit breaker, branch switches 12, 1
4 and 16, and then turn the operating lever 82, the micro switch 112 is first turned on, and the undervoltage release device and auxiliary switches 12, 14, 1 are turned on.
6 continues to close, and the opening/closing portion 58 is closed and held by the compression spring 96. In this state, the micro switch 114 is also closed, so by closing the branch switches 12, 14, and 16,
Even if the auxiliary switches 36, 38, and 40 are opened, the opening/closing portion 58 remains closed.

On the other hand, even if you forget to open the branch switches 12, 14, 16 when closing the circuit breaker 50, the respective auxiliary switches 36, 3
8 and 40 are open, even if the operating lever 82 is rotated, the undervoltage release device is activated and the opening/closing portion 58 is not closed.

As described above, the circuit breaker according to the present invention includes an undervoltage release device 22 whose input side is connected between the switching section 18, 58 and the input terminal of the circuit breaker to which it is connected, A first switch 24, 112 connected between the output side of the voltage release device and one output terminal, and a second switch connected between the output side of the undervoltage release device and the other output terminal. 26, 114, and the opening/closing portions 18, 5 of the first switch 24, 112 in conjunction with the movement of the operating lever 82.
an opening/closing mechanism that opens and closes the second
It is equipped with an opening/closing mechanism that opens and closes the switches 26, 114 in conjunction with the movement of the opening/closing section, and its input terminals and output terminals are connected to the bus bar 20, branch switches 12, 14, 16, and auxiliary switches as described above. By connecting the switches 36, 38, 40, etc., the protection circuit described in the object of the invention described above can be constructed.

[Brief explanation of the drawing]

Figure 1 is a connection diagram between a circuit breaker and a branch switch according to the present invention; Figure 2 is a perspective view showing the main parts of the circuit breaker according to the present invention; Figures 3 to 5 are circuit breaker A sectional view of the main parts of the circuit breaker; FIG. 6 is a diagram showing the operating stroke of the opening/closing part of the circuit breaker and the microswitch during the opening/closing operation of the circuit breaker. 10, 50...Circuit breaker, 12, 14, 16
... Branch switch, 22 ... Undervoltage release device, 2
4,112...Switch, 26,114...Second
switch, 82... operating lever, 126... actuator.

Claims (1)

[Claims] 1. In a circuit breaker equipped with an opening/closing part connected between an input terminal and an output terminal and an opening/closing mechanism having an operating lever for opening/closing this opening/closing part, the input side is connected between the opening/closing part and the input terminal. a first switch connected between the output side of the undervoltage release device and the second output terminal; and a first switch connected between the output side of the undervoltage release device and the third output terminal. a second switch connected between the first and second switches, an opening/closing mechanism that opens and closes the first switch in conjunction with the movement of the operating lever before the opening/closing section is opened/closed; A circuit breaker characterized by having an opening/closing mechanism that opens and closes in conjunction with each other.