JPS6258223B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lightning arrester unit suitably incorporated and used to construct a fuse detour circuit in a protector for telephone subscribers.

The principle of the current telephone protector is, from a circuit perspective, as shown by the solid line in Figure 1, a fuse F is inserted in series on the line L-I that connects the outside line L and the internal line I. The inner line side of the fuse F is grounded by a lightning arrester A, and when an instantaneous shock current (hereinafter referred to as a shock wave) caused by lightning etc. flows into the line, the lightning arrester is grounded by a circuit from L→F→A. A is discharged and discharged to the earth, and when a sustained current (hereinafter referred to as a continuous wave) due to high voltage contact flows in, fuse F is blown to cut off the high voltage. If a fuse detour circuit B is provided in such a safety circuit as shown by the imaginary line in Figure 1, the fuse detour discharge is performed to prevent fuse F from blowing out when a shock wave inflows, and the fuse detour circuit B is provided when a continuous wave inflows. The cutoff mechanism S is cut off by heat sensitivity due to continuous wave inflow, etc., and a discharge circuit of L→F→A is configured to obtain normal fuse blowing.

Therefore, in order to achieve the above-mentioned object, the present invention makes a circuit mechanism consisting of a lightning arrester and a heat-sensitive cut-off mechanism into a compact component, and simply incorporates this into a telephone subscriber's home safety device. The fuse detour circuit as described above can be easily configured. The present invention will be described in detail below based on illustrated embodiments.

In the figure, reference numeral 1 denotes a rectangular insulating case composed of a split case, and a hermet type lightning arrester A is installed in the insulating case 1, with its line electrode a and ground electrode b exposed on the outer surface of the case. The upper electrode plate 2 and the lower electrode plate 3 are attached to the electrode exposed surface of the insulating case 1.
and are assembled so as to be in contact with each electrode a and b. The upper electrode plate 2 is fitted into the groove 1a on the upper surface of the case 1, and is engaged with the groove wall 1c by inserting one end 2b into the stepped portion 1b provided at the groove end and inserting both ear portions 2a at the other end into the upper part of the lightning arrester storage chamber. The lower electrode plate 3 has an L-shaped claw plate 3a at both ends elastically connected to a stepped portion 1d on the side of the case. Engage and grasp. Similarly, a heat-sensitive cut-off mechanism S is installed adjacent to the lightning arrester A,
This is connected to the line electrode a and the electrode c opposite to the ground electrode b of the lightning arrester A, and the lead wire 4 is pulled out from the heat-sensitive cut-off mechanism S to the outside of the insulating case.
An external terminal 5 for connecting a fuse F is attached to the end of the lead wire 4. That is, the external terminal 5 for fuse connection and the lightning arrester A are connected via the lead wire 4 and the heat-sensitive cut-off mechanism S.

The connection between the lightning arrester A and the heat sensitive cut-off mechanism S follows the safety circuit shown in Fig. 1, and the cut-off mechanism S has one end connected to the outside wire side of the fuse F, and the other end connected to the inner wire side of the fuse F. , that is, line electrode a of lightning arrester A
In some cases, a lightning arrester without an electrode c is used, and the heat-sensitive interrupting mechanism S and the external lead wire 4 and its terminal 5 are connected to the line electrode a.

The drawing shows a specific example of the heat-sensitive cut-off mechanism S. As shown in the drawing, a part of the electrode c of the lightning arrester A is made to protrude outside to form an electrode terminal c', and solder is applied to the electrode terminal c'. The conductive wire 4' of the lead wire 4 is connected through a low melting point metal 6, such as a metal 6, to form a heat-sensitive disconnection contact S', and the heat-sensitive disconnection contact S' is elastically supported by a spring 7 that is elastically loaded in the case. and give it a detachment habit. As an example of elastic support by the spring 7, a coil spring 7 is inserted into the conductive wire 4' as shown in the figure, and is elastically loaded in the case 1 so as to be compressed. Apply cutting force. The contact S' always maintains the connection by the low melting point metal 6 against the disconnection force. In order to transmit the above-mentioned separation force by the spring 7 to the contact point S',
A pusher plate 8 is attached integrally with the conductor 4', one end of the spring 7 is supported by the pusher plate 8, and the other end is blocked on the lightning arrester A side to maintain a compressed state. That is, the elastic force accompanying the compression is transmitted to the conductor 4' via the pusher plate 8, and by applying a tensile force to the conductor 4', the breaking behavior of the contact point S is obtained. . In the illustrated embodiment, an insulating bush 9 is inserted into the connecting end of the conductor 4', and a coil spring 7 is inserted through the outer periphery of the insulating bush 9 so that the end is supported by the collar 9a of the bush 9. When the contact S' is disconnected due to the melting of the low melting point metal 6, the elastic force of the spring 7 pulls the end of the conductor 4' into the bush 9, and the dielectric strength voltage at the time of disconnection of the contact S' is increased. At the same time, insulation between the spring 7 and the lightning arrester A is achieved. Note that the spring 7 may be made of an insulating material.

In the above embodiment, the conductor 4' of the lead wire 4 is drawn into the case and also serves as the connection part of the heat-sensitive disconnection contact S'. In some cases, the metal 6 is connected to the electrode, and the other end is made to protrude outside the case and connected to the lead wire 4.

FIG. 5 illustrates the basic structure of the current telephone subscriber protector (for example, Utility Model Publication No. 51-45923). As shown in the figure, a pair of fuse holders 10, Hughes F on 11
At the same time, a bullet plate 12 connected to the fuse holder 11 on the extension side is extended, and a lightning arrester holding case 1 is inserted between the bullet plate 12 and a grounding board 13 inserted through the main body of the protector. The line electrode a of the lightning arrester A held in the lightning arrester holding case 1 is connected to the bullet plate 12, and the ground electrode c is connected to the ground board 13.
By contacting them respectively, L→F→12→
Thirteen discharge circuits are configured.
In the present invention, the lightning arrester unit having the above structure is inserted to form a discharge circuit as described above, and the lead wire 4 is inserted with its external terminal 5 into the screw base of the external fuse holder 10. The fuse detour circuit can be configured extremely simply by simply tightening. That is, as mentioned above, when a shock wave inflows due to lightning or the like, the shock wave does not pass through the fuse F, but passes through the lead wire 4, passes through the heat-sensitive cut-off mechanism S in the case 1, and is directly applied to the arrester A. Discharge and obtain earth discharge. As a result, the safety objective is achieved without blowing out the fuse F. Further, when a continuous wave flows in, it flows into the lead wire 4 and discharges the lightning arrester A as described above, but due to the sustained discharge, the electrode c is overheated and the low melting point metal 6 is melted. As a result, the heat-sensitive disconnection contact S' is disconnected,
The separation force of the spring 7 inside the case 1 safely separates them to a distance where they are completely separated, and the fuse bypass circuit is cut off. As a result, the continuous wave flows into the fuse F side, and while the above-mentioned normal discharge circuit continues to promote discharge, the fuse F reaches its melting point and blows out. As a result, the high voltage is properly shut off, and the flow into the telephone connected to the extension I is reliably blocked, thereby preventing electric shock accidents, equipment damage, etc.

As explained above, the present invention incorporates a lightning arrester in an insulating case, and exposes an upper electrode plate that conducts to the line electrode of the lightning arrester and a lower electrode plate that conducts to the ground electrode in the insulating case. and connect a lead wire to the electrode opposite the line electrode and the ground electrode or the line electrode via a low melting point metal, pull the lead wire out of the case, and attach an external terminal for fuse connection to one end of the lead wire. By providing a lightning arrester unit in which the connection part made of the above-mentioned low-melting point metal is supported by a spring that always gives a tendency to disconnect, shock wave inflow for the above purpose can be achieved by simply incorporating this into the current telephone subscriber home protector. A safety circuit equipped with the fuse bypass circuit that has both the fuse bypass discharge performance at the time and the self-shutdown performance when the connecting wave flows in can be constructed extremely easily. That is, this lightning arrester unit is inserted between the bullet plate 12 on the inner line side and the ground board 13 in the same way as the conventional lightning arrester case, and its external lead wire 4 is integrated with the fuse holder 10 on the outer line side using the external terminal 5. The fuse detour circuit mechanism as explained in Figure 1 can be completed within the protector by simply tightening and installing it, and the current protector does not require any modification, and the current arrester retaining method can be completed. It can be installed and used in the same manner as the above, and can be easily attached and detached for maintenance and inspection.

Incidentally, the heat-sensitive disconnection contact S may be made of a low melting point metal for the lightning arrester connecting conductor 4' or the terminal itself. Further, although the spring 7 is shown using its elastic force, it may be stretched to apply a tensile force to impart the above-mentioned breaking habit.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing an example of a telephone safety circuit equipped with a fuse detour circuit constructed by incorporating a protector into the present lightning arrester unit, Fig. 2A is an external view of the present lightning arrester unit, and Fig. B is the same. 3 is an exploded perspective view, FIG. 4 is an assembled cross-sectional view, and FIG. 5 is a side view schematically showing the structure of the device installed in a telephone subscriber protector. DESCRIPTION OF SYMBOLS 1... Insulating case, 2, 3... Upper and lower electrode plates, 4... Lead wire, 4'... Lightning arrester connection conducting wire, 6... Low melting point metal, S... Heat sensitive disconnection contact, 7... Disconnection spring.

Claims (1)

[Claims] 1. Incorporate a lightning arrester into an insulating case, and install an upper electrode plate conductive to the line electrode of the lightning arrester and a lower electrode plate conductive to the ground electrode in the insulating case in an exposed state, and install the above line electrode and Connect a lead wire to the electrode or line electrode facing the ground electrode via a low-melting point metal, pull the lead wire out of the case, attach an external terminal for fuse connection to one end of the lead wire, and connect the connection part made of the above-mentioned low-melting point metal. A lightning arrester unit for a telephone subscriber protector, characterized in that it is supported by a spring that imparts the above-mentioned disconnection behavior.