JPH0127104Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to the opening/closing mechanism of a clamp sensor, and more specifically, the invention relates to an opening/closing mechanism of a clamp sensor.
The present invention relates to an opening/closing mechanism for a clamp sensor, which is particularly suitable for detecting minute currents, and which opens and closes a pair of magnetic cores by sliding them along their abutting surfaces.

FIG. 1 shows a typical conventional clamp sensor for detecting minute currents. That is, the clamp sensor 1 includes a pair of magnetic cores 3 and 4 that are combined with each other to form, for example, a rectangular annular body so as to surround the electrical path 2 to be measured. The core 3 is fixed to the tip of a lower frame 5 of the housing that is elongated. The other magnetic core 4 is attached to the tip of a slide member 7 that is slidable relative to the upper frame 6 of the housing. Note that this slide member 7 has a spring 8 interposed between it and the upper frame 6, so that the magnetic core 4 is connected to the magnetic core 3.
are biased to a forward position in combination to form a closed magnetic circuit. Therefore, when the slide member 7 is pulled backward against the spring 8, the upper magnetic core 4 slides along its abutting surface, and the electrical path to be measured 2 can be inserted into the lower magnetic core 3. However, this conventional example has the following drawbacks. That is, in order for the upper magnetic core 4 to completely return when the hand is released from the slide member 7, it is preferable that the spring 8 has a strong biasing force, but if a strong spring is used, the slide member 7 will be pushed backward. It requires a large amount of operating force to slide, making it inconvenient to handle. In addition, the electrical path to be measured 2
In order to make it easier to insert the slide member 7 into the lower magnetic core 3, it is preferable that the amount of movement of the slide member 7 is larger, but if this is done, it becomes impossible to further downsize the slide opening/closing mechanism.

This idea was made in view of the conventional circumstances mentioned above, and its purpose was to reduce the magnetic core to almost 1/2 of the conventional one.
It is an object of the present invention to provide an opening/closing mechanism for a clamp sensor that can be easily opened/closed with two strokes and is suitable for downsizing.

Hereinafter, this invention will be described in detail with reference to an embodiment shown in the accompanying drawings.

As exemplified in FIG.
It is equipped with a pair of magnetic cores 3 and 4 that are combined with each other to constitute, for example, a rectangular annular body so as to be able to surround the upper magnetic core 4. It is attached to the tip of the slide member 7 as in the conventional example. In this invention, the lower magnetic core 3 is also slidably attached to the frame 5 of the housing.
That is, this clamp sensor 10 has a sub-frame 12 that is slidably inserted into the lower frame 5 of the housing, and a lower part that is paired with the upper magnetic core 4 is attached to the tip of this sub-frame 12. 3 magnetic cores are installed. In addition, in this case, the magnetic core 3
A suitable shield member 13, which makes a pair with the shield member 11, is disposed around the shield member 11. Further, a spring 8 is interposed between the slide member 7 and the upper frame 6 of the housing.

Each of the slide member 7 and the subframe 12 is provided with racks 14 and 15 that extend parallel to each other, and these racks 14 and 15
A pinion 16 that is pivotally supported by the housing frame is disposed between the housing frame and the housing frame.

In the above configuration, when the slide member 7 is slid toward the right in FIG. 2 against the spring 8,
The pinion 16 rotates clockwise in the figure, and in conjunction with this, the subframe 12 moves to the left in the figure. Therefore, the magnetic cores 3 and 4 slide in opposite directions along their abutting surfaces, and the fourth
As shown in the figure, the lower magnetic core 3 is opened so that the path to be measured 2 can be inserted therein. In this state shown in FIG. 4, the slide member 7
When you let go of the slide member 7, the spring 8
At the same time, the subframe 12 is pushed back toward the front position by the urging force of A closed magnetic circuit surrounding the electric path 2 is constructed.

Note that, although a CT winding and a Hall element are actually attached to either one of the magnetic cores 3 and 4, they are not shown in this embodiment for the sake of convenience.

As is clear from the above description of the embodiment, according to this invention, the sub-frame 12 having the lower magnetic core 3 is connected to the two racks 14 and 15 with respect to the slide member 7 having the magnetic core 4 described above. Since the slide member 7 slides in the opposite direction via the pinion 16, the amount of movement of the slide member 7 required to open and close the magnetic cores 3 and 4 is only half that of the conventional one. Therefore, the spring 8 only needs to be small, and the overall structure can be made more compact, which has significant effects.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional example, Fig. 2 is a sectional view of essential parts showing an embodiment of this invention, Fig. 3 is a sectional view taken along the line A-A in Fig. FIG. 3 is a cross-sectional view for explaining the operating state of the embodiment shown in FIG. 2; In the figure, 2 is the electrical path to be measured, 3 and 4 are magnetic cores, 5 is a lower frame, 6 is an upper frame, 7 is a slide member 7, 8 is a spring, 11 and 13 are shield members, 12 is a subframe, 14, 15 is a rack, and 16 is a pinion.

Claims (1)

[Claims for Utility Model Registration] An opening/closing mechanism for a clamp sensor that relatively slides a pair of magnetic cores that are combined in an annular shape and surround a measured electrical path along a plane parallel to their abutting end surfaces, The opening/closing of the clamp sensor is characterized in that each of the magnetic cores is connected to a rack extending parallel to each other along the sliding direction thereof, and a pinion is interposed between the racks. mechanism.