JPH0449208B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a disconnector equipped with a locking device that prevents the disconnector from opening due to erroneous operation or malfunction when the disconnector is in an energized state.

"Prior Art" Generally, a disconnector is a device in an electric circuit that does not switch on or off a load, so it is necessary to prevent the load current from being cut off due to erroneous operation or malfunction. In other words, it is necessary to prevent a disconnector from opening when it is energized, but conventionally there is no locking device that directly detects whether the disconnector is energized and prevents it from opening if it is energized. Nakatsuta. Therefore, as an indirect method, the open/closed state of the circuit breaker is output as a contact by the auxiliary switch of the circuit breaker operating device, and this output is input as an electrical interlock condition to the circuit breaker's operating circuit. An interlock is provided so that the disconnector can only be opened and closed when the disconnector is open.

``Problem to be solved by the invention'' The above interlock is possible when a shingle breaker is installed near the disconnect switch, but it cannot be used when there is no shingle breaker near the disconnect switch. .
Therefore, in this case, the operator performs the opening/closing operation of the disconnector after confirming that the line has been switched and confirming that the disconnector is in an open state. Therefore, due to human error such as misidentification of the open/closed state of the disconnector, there was a risk of a so-called erroneous operation of opening the disconnector when the disconnector was in the closed state.

"Means for Solving the Problems" The present invention provides a disconnector equipped with a lock device that directly detects whether or not the disconnector is energized and prevents the disconnector from performing an opening operation when the disconnector is energized. The purpose of this is to provide a current detection section near the fixed contact that detects the current flowing through the current-carrying section, and a movable device that is connected to this current detection section and is actuated by the output of this current detection section. A locking device is provided to prevent the contact from separating from the fixed contact.

``Operation'' When the disconnector is energized, the locking device is activated by the output of the current detection section, and the movable contact cannot be separated from the fixed contact. Therefore, even if a command to open the circuit is issued by mistake while the circuit is energized, the lock device maintains the energized state, thereby preventing malfunction.

Further, when the disconnector is de-energized, there is no output from the current detection section, so the lock device does not operate and the disconnector can be opened and closed.

Embodiment Next, prior to describing an embodiment of the present invention, an outline of a twist type horizontal two-point disconnect device will be explained based on FIGS. 4 and 5.

Support insulators 2 and 2a are placed at both ends of the base 1, and a rotary insulator 3 is rotatably supported at the center. A blade 5 having movable contacts 4 at both ends is fixed to the upper end of the rotary insulator 3. External electric wires 6, 6a are connected to the upper ends of the support insulators 2, 2a, and the movable contact 4
Fixed contacts 7, 7a that can grip the terminal are fixed. This fixed contactor 7 has a finger 9 attached to a support 8 fixed to the support insulator 2, and a spring 10 that applies contact pressure to the finger 9.
and a pin 11, etc. Further, the fixed contact 7a is also constructed in exactly the same manner as the fixed contact 7.

On the other hand, the twisting mechanism of the blade 5 is composed of a fixed contact stopper 12 fixed to the support 8, a knock pin 13 fixed to the blade 5, and a movable contact stopper 14.

Figures 5a to 5c show the process of circuit closing operation. When the circuit closing operation is performed by an operating device (not shown) in the open state of the disconnector, the blade 5 rotates and the movable contact 4 contacts the fixed contact. When reaching the vicinity of the contacts 7 and 7a, the knock pin 13 comes into contact with the fixed contact stopper 12. This state is shown in FIG. 5a.

In this state, the blade 5 attempts to rotate further, but since the knock pin 13 is in contact with the fixed contact stopper 12 as described above, the blade 5 begins to twist as shown in FIG. 5b.

When the blade 5 is twisted and the movable contact 4 is gripped by the fingers 9, the movable contact stopper 14 comes into contact with the fixed contact stopper 12, the twisting is stopped, and the closing operation of the disconnector is completed.

Next, an embodiment of the present invention will be described based on FIGS. 1 to 3. Note that the same parts as those in the above-mentioned prior art are given the same numbers, and the explanation thereof will be omitted. A current-carrying portion 21 is formed between the fixed contact 7 and the external electric wire 6, and a current detecting portion 22 such as a through-type current transformer or an optical current transformer is attached to this current-carrying portion 21. A locking device 23 having a locking pin 23a is connected to the current detecting section 22, and the locking pin 23a is operated by the output of the current detecting section 22, thereby causing the moving contact stopper 14 to move in the opposite direction from the fixed contact stopper 13. configured to prevent it.

That is, when the disconnector is in the energized state, the output of the current detection section 22 is input to the lock device 23, the lock pin 23a protrudes as shown in FIG. movement to the opposite side is prevented, so the disconnector is configured not to open. on the other hand,
When the disconnector is de-energized, there is no output from the current detection section 22, so the lock pin 23a of the locking device 23 does not protrude as shown in FIG. 3b, and the disconnector can be opened.

In the device of the present invention, even if a command to open the disconnector is issued due to an erroneous operation while the disconnector is energized, the rotation of the movable contact stopper 14 is restricted by the lock pin 23a of the lock device 23. , the blade 5 cannot be twisted, and as a result, the movable contactor 4 remains in contact with and gripped by the fingers 9. Therefore, the disconnector is not opened and does not cut off the load current, so accidents caused by erroneous operation can be reliably prevented.

In the above embodiment, the present invention was applied to a twist type horizontal two-point disconnect device.
Of course, it can be applied to various types of disconnectors such as horizontal two-point disconnectors and vertical disconnectors that do not require twisting.

``Effects of the Invention'' The present invention does not use a method of interlocking the opening and closing operations of a disconnector using a disconnector as in the prior art, but directly checks whether or not the disconnector is energized. Since the opening operation can be prevented,
Not only can it be applied even when no disconnector is installed near the disconnector, but it can also reliably prevent malfunctions caused by erroneous commands.

Furthermore, since the current detection part is mounted on the conductive part of the disconnector, it does not require a withstand voltage unlike a bushing type current transformer, so it is very economical.

[Brief explanation of drawings]

Figure 1 is a front view showing one embodiment of the present invention, Figure 2 is a front view showing one embodiment of the present invention;
The figure is a side view of Figure 1, Figures 3a and 3b are operation diagrams of the locking device, Figure 4 is a front view showing an overview of the horizontal two-point disconnector, and Figure 5 is the circuit closing operation process. FIG. In the figure, 4 is a movable contact, 5 is a blade,
7 and 7a are fixed contacts, 12 is a fixed contact stopper, 13 is a knock pin, 14 is a movable contact stopper, 21 is a current conducting section, 22 is a current detecting section, 23 is a locking device, and 23a is a locking pin.

Claims (1)

[Claims] 1. In a disconnector that is opened and closed by a movable contact provided at the tip of a blade coming into contact with and separating from a fixed contact, a current detection unit is provided near the fixed contact to detect the current flowing through the current-carrying part. A disconnector further comprising a lock device connected to the current detection section and actuated by the output of the current detection section to prevent the movable contact from detaching from the fixed contact.