JPH059801Y2 - - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention (Field of Industrial Application) The present invention relates to an electric shock prevention cover for a discharge type fuse used in a cylindrical cutout.

(Prior Art) As shown in FIG. 7, a discharge type fuse tube 6 that is removably attached to the cylindrical cutout 1 is connected to the upper electrode 11 of the cylindrical cutout 1 at the upper end of the insulating tube 6a. An upper contact 12 to be released is fixed, and a cylindrical cutout 1 is provided at the bottom of the insulating cylinder 6a.
An annular lower contact 7 that comes into contact with and separates from the lower electrode 5 is loosely fitted. Further, a locking tube 8 is attached to the outer periphery of the lower end of the insulating tube 6a. This locking tube 8 is
It consists of a screw seat 8a fitted on the outer periphery slightly above the lower end of the insulating tube 6a, and a display tube 8b provided at the bottom of the screw seat 8a.

Furthermore, a fuse element 13 is connected to the lower end of the upper contactor 12 in the insulating cylinder 6a,
A lead wire 10 is connected to the lower end of the fuse element 13. The lead wire 10 is connected to the outer surface of the lower contactor 7 by a lead wire tightening screw 9 by folding back the lower end opening of the insulating tube 6a. The portion of the lead wire 10 from the folding point at the lower end of the insulating tube 6a to the connection point on the outer surface of the lower contactor 7 was arranged along the outside of the display tube 8b and was exposed to the outside. .

(Problem to be solved by the invention) Therefore, when inspecting the cylindrical cutout 1,
There was a risk that the worker would receive an electric shock if he touched the exposed lead wire 10.

(Means for Solving the Problems) In order to solve the above-mentioned problems, in this invention, a lower contact having an annular contact portion is loosely fitted into an insulating cylinder having an upper contact fixed to the upper end, and the lower end of the insulating cylinder is A locking cylinder is fixed to the part, a coil spring is interposed between the lower contact and the locking cylinder, and one end is connected to the upper contact through a fuse element by passing through the insulating cylinder. An electric shock prevention cover that is removably attached to the lower end of a discharge type fuse cylinder, which is equipped with a fuse whose lower end is bent at the lower end of the locking cylinder and is connected to the lower contact. The insulating main body is formed into a cylindrical shape so as to cover the lead wire exposed from the locking cylinder and to allow the downward movement of the insulating cylinder when the fuse element is cut off, and the upper part has the lower contact An elastic locking portion that elastically locks the locking portion protruding on the outer periphery of the child is provided, and the outer periphery of the main body includes:
A structure is adopted in which a protrusion is provided for attachment operation.

(Function) To attach the electric shock prevention cover 21 configured as described above to the discharge type fuse tube 6, first fit the upper end opening of the electric shock prevention cover 21 to the lower part of the discharge type fuse tube 6, and then the electric shock prevention cover 21 is attached to the discharge type fuse tube 6. The elastic locking portion 27 of 21 is locked to a locking portion 19 protruding from the outer periphery of the lower contactor 7, and the electric shock prevention cover 21 is attached to the discharge type fuse 6. After this, in order to attach the discharge type fuse tube 6 to the cylindrical cutout 1, use the protrusion 31 on the outer periphery of the electric shock prevention cover 21 at the tip of the operation rod, which is larger in diameter than the conventional insulated tube operation rod. Then, the electric shock prevention cover is attached, and then the release type fuse tube 6 is attached to the cylindrical cutout 1.

(Example) An example embodying this invention will be described below with reference to FIGS. 1 to 6. In FIG. 1, the same members as those in FIG. 7 are given the same reference numerals.

The main body insulator 1 of the cylindrical cutout 1 has an insulating cylinder storage hole 2 formed therein;
An enlarged-diameter portion 3 is formed at the lower part of the tube via a stepped portion 4, and the lower end thereof is formed to open downward. An upper contact (not shown) connected to the power supply side is provided at the upper part of the insulating cylinder storage hole 2, and a lower electrode 5 is attached to the upper part of the enlarged diameter part 3, and a discharge type is provided between the two electrodes. Fuse tube 6
is removably attached.

In this discharge type fuse 6, an annular lower contact 7 which is held in contact with the lower electrode 5 of the cylindrical cutout 1 is loosely inserted into the lower outer periphery of the insulating cylinder 6a, and between the lower contact 7 and the insulating cylinder 6a. A coil spring (not shown) whose upper end is locked to the lower contactor 7
is interposed. A flange 19 is formed on the outer periphery near the lower end of the lower contact 7 as a locking portion for regulating the insertion condition of the operating rod.
Two locking protrusions 20 (only one shown) are provided below 9 at a distance of 180 degrees from each other. At the lower end of the insulating cylinder 6a, a locking cylinder 8 is provided below the lower contactor 7, and a spring seat 8a provided at the upper part of the locking cylinder 8 locks the lower end of the coil spring. Furthermore, to explain in detail the display tube 8b that constitutes the lower end of the insulating tube 6a and the lower part of the locking tube 8, the lower end of the insulating tube 6a has a locking groove 6b.
A notch is formed in the display tube 8b, and a split groove 8c is formed on the side surface of the display tube 8b so that the cross section of the display tube 8b has a C-shape. Then, the position of the split groove 8c of the display tube 8b is adjusted to the position of the locking groove 6b of the insulating tube 6a.
A lead wire 10, which will be described later, is arranged along the locking groove 6b and the split groove 8c. A fuse element (not shown) connected to the lower end of the upper contactor (not shown) is provided in the insulating tube 6a, and a lead wire 10 is connected to the lower end of the fuse element. This lead wire 10 is folded back at the locking groove 6b of the lower end opening of the insulating tube 6a, and further,
The end portion of the lead wire 10 is tightened and fixed to the outer surface of the lower contactor 7 by a lead wire tightening screw 9.

The coil spring is in a compressed state when the fuse element is connected to the lower contact 7 via the lead wire 10.

Further, the locking protrusion 20 is locked to a locking portion of a fitting cylinder portion of a known operation rod used when removing the discharge type fuse tube 6 from the cylindrical cutout 1, etc. In the embodiment, it is used to prevent the electric shock prevention cover 21 from rotating relative to the lower contact 7 when the electric shock prevention cover 21 is attached.

Next, the electric shock prevention cover 21 will be explained with reference to FIG.

The electric shock prevention cover main body 21 is integrally formed of polyethylene resin into a cylindrical shape whose inner periphery is larger than the outer periphery of the locking tube 8 . An enlarged diameter part 22 is provided at the upper part of the electric shock prevention cover 21, and a locking protrusion 23 is provided on the inner peripheral surface of the enlarged diameter part 22.
Further, below the locking protrusion 23, a locking groove 24 is provided in the circumferential direction of the inner peripheral surface of the enlarged diameter portion 22. From the upper end of the enlarged diameter part 22 to the slightly lower part of the enlarged diameter part 22, slits 25 are formed at five locations at 60 degree intervals as shown in FIG. The lower side of the figure) has a large notch and is provided with an opening groove 26. Electric shock prevention cover 2
1 is separated into six locking pieces as elastic locking portions 27 by these slits 25 and opening grooves 26, and each locking piece 27 has elastic force.
Further, a tapered surface 28 is formed on the inner peripheral surface below the opening groove 26 in an oblique shape so as to expand from below toward the opening groove 26, and the electric shock prevention cover 21 is attached to the lower contactor 7. In some cases, the lead wire 10 is designed to pass through the tapered surface 28 and the opening groove 26. Further, on the inner periphery of the electric shock prevention cover 21, the electric shock prevention cover 21 is attached to the lower contact 7.
The locking protrusion 20 of the lower contactor 7 when attached to the
A detent groove 29 is recessed downward from the locking groove 24 at a position corresponding to the locking protrusion 20.
The anti-rotation groove 29 is adapted to engage with the rotation stopper groove 29.

A flange 30 is provided on the outer peripheral surface of the electric shock prevention cover 21 in the circumferential direction, and the upper surface of the flange 30 coincides with the lower end of the opening groove 26 . Furthermore, locking protrusions 13 are formed slightly below the flange 30 and are spaced apart from each other by 180 degrees, and furthermore, on substantially the same circumference of the locking protrusions 31 are formed anti-shake protrusions 3 that are spaced from each other by 180 degrees.
2 is provided.

Next, the operation rod 33 for attaching the discharge type fuse tube 6 equipped with the electric shock prevention cover 21 to the cylindrical cutout 1 will be explained with reference to FIGS. 5 and 6.

The operation rod 33 used in this embodiment has a fitting tube portion 34 which is different from a fitting tube portion (hereinafter referred to as the first fitting tube portion 34) of a known operation rod used when replacing a discharge type fuse tube. Another fitting tube portion (hereinafter referred to as the second fitting tube portion 35) configured in substantially the same manner as
Two connections are made.

First, the first fitting cylinder part 34 will be explained.
A rod 36 is attached to the base end of the first fitting cylinder 34, and a fitting hole 37 is bored from the distal end of the first fitting cylinder 34 toward the base end. This fitting hole 37 consists of a large diameter portion 37a on the distal end side and a small diameter portion 37b on the proximal end side. A screw hole 38 communicating with the small diameter portion 37b of the fitting hole 37 is threaded on the side of the first fitting cylinder 34, and the screw hole 38 has a screw 39.
is screwed in. On the inner peripheral surface of the tip of the fitting hole 37,
A pair of L-shaped protruding engaging portions 37c (only one of which is shown) is provided at opposing positions. Further, an annular holding member 40 is provided in the large diameter portion 37a of the fitting hole 37, and is urged toward the distal end by a coil spring 41 provided in the large diameter portion 37a.

The second fitting cylindrical part 35 has a fitting hole 43 and an L-shaped engagement part 44 that are configured almost similarly to the first fitting cylindrical part 34.
(only one shown), holding member 45, coil spring 46
The difference is that the inner diameters of the fitting hole 43, the presser member 45, etc. are formed slightly larger than the inner diameters of the fitting hole 37 of the first fitting cylinder 34 and the presser member 40. A connecting screw portion 47 is threaded at the base end of the second fitting cylinder portion 42, and an engaging step portion 48 whose diameter is larger than that of the connecting screw portion 47 is formed at the opening of the connecting screw portion 47. It is provided. Further, a connecting screw portion 4 is provided on the side of the second fitting cylinder portion 35.
A screw hole 49 communicating with 7 is threaded, and the same screw hole 49 is threaded.
A screw 50 is screwed into the hole 9.

The adapter 51 that connects the first and second fitting cylinder parts 34 and 35 is formed into a substantially cylindrical shape. A tip threaded portion 52 is threaded on the tip side of the adapter 51, and a screw hole 53 is threaded on the side of the tip threaded portion 52. A locking flange 54 is provided at the base end of the tip threaded portion 52, and a stepped portion 55 having approximately the same diameter as the tip threaded portion 52 is provided immediately at the proximal side of the locking flange 54.
is formed. Further, from this stepped portion 55, a mounting tube 56 whose diameter is reduced from that of the stepped portion 55 extends toward the base end side, and a screw hole 57 is threaded on the side of the mounting tube 56. Further, a vibration preventing protrusion 58 is formed on the outer peripheral surface of the stepped portion 55.

In order to connect the first and second fitting cylinder parts 34 and 35 using this adapter 51, first, the tip threaded part 52 of the adapter 51 and the connecting thread part 47 of the second fitting cylinder part 35 are screwed together, and then Tighten the screw 50, and insert the same screw 50 into the screw hole 57 of the tip threaded portion 52 of the adapter 51. (Normally, the adapter 51 is used while being fixed to the second fitting cylinder part 35.) Next, the mounting cylinder 56 of the adapter 51 is inserted into the fitting hole 37 of the first fitting cylinder part 34. Then, further tighten the screw 39 and screw it into the screw hole 57 of the mounting tube 56 of the adapter 51. At this time, the anti-shake protrusion 58 comes into contact with the inner periphery of the large part 37a of the first fitting cylinder 34, and the adapter 51 is prevented from shaking.

The electric shock prevention cover 21 is attached to the discharge type fuse tube 6 constructed in this manner, and the discharge type fuse 6 is further attached to the cylindrical cutout 1 using the operating rod 33 in the following manner.

First, match the position of the lead wire tightening screw 9 of the lower contactor 7 of the discharge type fuse tube 6 with the position of the opening groove 26 of the electric shock prevention cover 21, and
1 to the lower part of the open fuse tube 6. At this time, the locking protrusions 23 of each locking piece 27 of the electric shock prevention cover 21 come into contact with the flange 19 of the lower contactor 7, and each locking piece 27 expands slightly against its own elastic force. Further, when pressed, the flange 19 fits into the locking groove 24 of each locking piece 27, and each locking piece 2
7 returns to its original state and elastically locks the flange 19, and the electric shock prevention cover 21 is attached to the discharge type fuse tube 6. In addition, when the electric shock prevention cover 21 is attached to the discharge type fuse tube 6 in this way, the locking protrusion 20 of the lower contactor 7 is engaged with the rotation prevention groove 29 of the electric shock prevention cover 21, and the electric shock prevention cover 21 is prevented from shifting in its mounting position.

Next, the fitting hole 43 of the second fitting cylinder part 35 of the operating rod 33 is engaged with the lower end of the electric shock prevention cover 21 attached to the discharge type fuse cylinder 6 . At this time, after the holding protrusion 31 retreats the holding member 45 into the fitting hole 44 against the biasing force of the coil spring 46, the electric shock prevention cover 21 and the operating rod 3 are removed.
3 is rotated relative to each other, and the locking protrusion 31 is locked to the engaging portion 44 as shown in FIG. In addition, the anti-shake projection 32 comes into contact with the inner circumferential surface of the fitting hole 43, and the electric shock prevention cover 21 is prevented from shaking.

Thereafter, the discharge type fuse tube 6 with the electric shock prevention cover 21 attached is attached to the cylindrical cutout 1 by using the operation rod 33 in the same manner as when attaching a normal discharge type fuse tube to the cylindrical cutout. Installing.

As described above, when the electric shock prevention cover 21 of the present invention is attached to the lower part of the discharge type fuse tube 6 of the cylindrical cutout 1, it covers the display tube 8b and the intermediate electrode 8a as shown in FIG. Then, the lead wire 10 exposed to the outside near the display tube 8b and the intermediate electrode 8a is also covered with the electric shock prevention cover 21, and there is a risk that a worker may come into contact with the lead wire 10 and receive an electric shock when inspecting the cutout 1. can be eliminated. Further, when the electric shock prevention cover 21 is attached, the lead wire 10 passes through the tapered surface 28 and the opening groove 26 of the electric shock prevention cover 21, so that it is not hindered in any way.

Further, when removing the ejection type fuse tube 6 to which the electric shock prevention cover 21 is attached from the cylindrical cutout 1, the same operation as when removing a normal ejection type fuse from the cylindrical cutout is performed. Furthermore, it is also possible to attach this electric shock prevention cover 21 to a discharge type fuse that is already attached to the cylindrical cutout using the operating rod of this embodiment.

Note that this electric shock prevention cover 21 is formed into a cylindrical shape that allows the insulating tube to move downward, so even if the insulating tube 6a etc. moves downward to cut off the fuse element, it will not cause any hindrance to its operation. do not have.

With the above configuration, this embodiment provides the following unique effects.

(a) When carrying out repairs, inspections, etc. in the vicinity of the cylindrical cutout 1, it is possible to prevent a worker from receiving an electric shock from the lead wire of the discharge type fuse tube 6.

(b) Since it can be attached to the existing ejection type fuse tube 6 as is, there is no need to incur any additional costs.

(c) When attaching the electric shock prevention cover 21 to the discharge type fuse tube 6, the discharge type fuse tube 6 can be easily and safely attached without removing it from the cutout 1.

(d) The conventional operating rod 33 can also be used as is by simply inserting a new component into the fitting tube portion of the operating rod 33.

(e) When the electric shock prevention cover 21 is attached to the discharge type fuse tube 6, the locking protrusion of the lower contact and the rotation prevention groove of the electric shock prevention cover 21 engage with each other, so that the electric shock prevention cover 21 There is no risk of the installation position shifting.

(g) Since the lead wire passes through the tapered surface and opening groove of the electric shock prevention cover 21, it will not be subjected to excessive force. Furthermore, there is no problem with the existing functions of the discharge type fuse tube, such as the downward movement of the display tube.

(a) By providing this electric shock prevention cover 21, the display cylinder 8b is hidden behind the electric shock prevention cover 21 and cannot be seen under normal conditions, and the difference from the protruding operation of the display cylinder when the fuse element is cut off is clearly visible. become.

Note that the present invention is not limited to this embodiment, and any changes may be made, such as increasing the diameter of the enlarged diameter portion 22 at the top of the electric shock prevention cover 21 to the flange side, as shown by the two-dot chain line in Fig. 4. is also possible.

Effects of the invention As detailed above, according to the present invention, it is possible to prevent workers from receiving electric shock from the lead wire of the discharge type fuse during repairs or inspections near the cylindrical cut-out, and it is also possible to Since it can be attached to a type fuse as it is and does not impair the function of the discharge type fuse, there is no need to incur additional costs. In addition, a discharge type fuse equipped with an electric shock prevention cover can be easily and safely attached to or removed from a cylindrical cutout using an operating rod, just like a conventional discharge type fuse. It can also be done while attached to the cylindrical cutout.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway sectional view of an electric shock prevention cover according to an embodiment of the present invention attached to a discharge type fuse tube, Fig. 2 is a plan view of the electric shock prevention cover according to the same embodiment, and Fig. 3 is a FIG. 4 is a front view of the electric shock prevention cover, FIG. 4 is a sectional view of the same electric shock prevention cover, and FIG. Cutaway cross-sectional view,
FIG. 6 is a partially cutaway sectional view showing a state in which the electric shock prevention cover and the operating rod are connected, and FIG. 7 is a partially cutaway sectional view of a cutout equipped with a conventional discharge type fuse tube. 6...Discharge type fuse tube, 6a...Insulation tube, 7
... lower contactor, 8 ... locking cylinder, 10 ... lead wire, 19 ... locking part, 27 ... elastic locking part, 31
……protrusion.

Claims (1)

[Claims for Utility Model Registration] A lower contact having an annular contact portion is loosely fitted into an insulating tube with an upper contact fixed to the upper end, and a locking tube is fixed to the lower end of the insulating tube, and the lower contact is fixed to the lower end of the insulating tube. A coil spring is interposed between the child and the locking cylinder, and the coil spring is inserted through the insulating cylinder, and one end thereof is connected to the upper contact through a fuse element, and its lower end is bent at the lower end of the locking cylinder. In the electric shock prevention cover that is removably attached to the lower end of a discharge type fuse tube, which is equipped with a fuse equipped with a lead wire connected to a lower contact at a The insulating cylinder is formed into a cylindrical shape so as to cover the lead wire exposed from the fuse element and to allow downward movement of the insulating cylinder when the fuse element is cut off. 1. An electric shock prevention cover for a discharge type fuse cylinder, characterized in that an elastic locking portion for elastic locking is provided, and a protrusion for attachment operation is provided on the outer periphery of the main body.