JPH09308070A - Fixing packing for armored cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure a clamping function, a waterproofing function, and a grounding function with a simple structure by providing a clamp part with a claw piece which includes a metallic grounding part at its front part, a waterproofing part of thick circumferential wall at its middle part, and elasticity at its base end part. SOLUTION: When male and female screw parts 53, 55 are screwed into cable fixing hardware 51, the taper part 46 of the nail piece 43 of a ring body is pressed by the taper part 56 of a cover 54, and the taper part 38 of the front end part of a fixing packing 30 and the external end part of a metallic piece are brought into pressure contact with the taper inner circumferential wall 57 of a hardware main body 52. The inner end part of the metallic piece is brought into contact with a metallic tubular part 59, and a covered part 58 is brought into contact with a tube hole part of the packing main body tightly. Feeble current which leaks from the covered part 58 is grounded by an apparatus through the metallic piece of the ground part and the hardware main body 52 brought into contact with the metallic tubular part 59. Waterproofing property is ensured by contacting a thick circumferential wall 47 of a waterproofing part with the inner circumferential wall of the cover 54, and respective claw pieces 43 of the clamp part pressurize a cable 50, thus preventing anti-loose. It is thus possible to ensure three functions with a simple structure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixed packing for an armored cable, and more particularly to a waterproof function, a clamp function (prevention function) and a grounding function (ground function) of a cable insertion portion which is brought into contact with the outer periphery of the armored cable.
In a fixed packing for an armored cable mainly used for a cable fixing metal fitting, a waterproof packing, a clamp portion, and a grounding portion are compactly integrated with each other.

[0002]

2. Description of the Related Art Conventionally, an external conductor connected to a device such as a wiring box of an explosion-proof solenoid valve or other connection box is attached with a cable fixing metal fitting to the equipment for protection thereof, and is inserted into the inserting portion of the fixing metal fitting. It is inserted and firmly fixed. The cable fixing bracket that can be attached to the wall of this type of equipment has reliable waterproofness at the cable insertion point for ensuring safety,
Cable retention prevention properties are required, and products with various improvements have been developed in terms of their structure.

This kind of cable fixing metal fitting has a cylindrical packing for preventing rainwater from moving through the cable insertion portion, a clamp for firmly fixing the cable, and a weak current leaking from the cable to flow to the outside. Arranged with a ring metal fitting for grounding for smooth power transmission and configured to achieve the above object.

An example of a conventional cable fixing bracket will be described with reference to FIG. The cable fixing fitting 1 is composed of a tubular metal fitting main body 2 and a tubular metal cover 3, which are screwably connected to each other via these male and female screw portions 4 and 5. A tubular packing 7 is arranged in the insertion portion 6 in the metal fitting body 2. In the insertion portion 8 in the cover 3, a cylindrical drum-shaped elastic body 10 is arranged with a cylindrical metal gland 9 interposed on the packing 7 side. This elastic body 10
As shown in FIG. 11, the middle portion is a thick portion 11, and a plurality of metal pieces 14, 15, ... Formed in a substantially U-shape are attached to the left and right tapered outer peripheral surfaces 12, 13. 16
Is a washer inserted in a neck portion 18 provided at the tip of the gland 9.

In such a cable fixing bracket 1,
By passing the armored cable 17 through the insertion portions 6, 7, ... Of each member and screwing in the male and female screw portions 4 and 5,
The metal fitting body 2 and the cover 3 are firmly connected, and the tip end surface of the neck portion 18 of the gland 9 arranged in the cover 3 presses the packing 7 via the washer 16.

At this time, the tip surface 19 of the packing 7 contacts the taper portion 20 of the metal fitting body 2, and the packing 7 is
Since there is no escape area on the outside, it bulges toward the inner peripheral side and fastens the outer periphery of the armored cable 17 in a pressure-contacting manner, and mainly performs a clamp function for preventing the armored cable 17 from coming off and a waterproof function. Further, since the elastic body 10 similarly presses against the taper portion 21 of the gland 9, the elastic body 10 bulges toward the inner peripheral side to fasten the armored cable 17 in a pressure contact state, and has a clamp function for preventing slippage and waterproofing. The metal pieces 14, 15, ... Of the elastic body 10 perform the function and the armored cable 1
The current leaking from the cable is taken out by pressing it against the metal surface of 7.

[0007]

The elastic body 10 includes:
It has a clamp function, a waterproof function and a grounding function. However, since the metal pieces 14 and 15 of the elastic body 10 are configured to be attached from the tapered outer peripheral surfaces 12 and 13 to the insertion portion 22, the insertion portion 22 that comes into contact with the armored cable 17 is used.
Side elastic body surface is insufficient, it is not possible to firmly fasten in a pressure contact state,
There is a problem that the clamp function of preventing the armored cable 17 from being pulled out is not sufficient.

The present invention has solved the above-mentioned problems, and its object is to compactly integrate a waterproof portion, a clamp portion, and a grounding portion which are simple in construction, can be provided at low cost, and are easy to handle. The purpose is to provide a fixed packing for armored cables.

[0009]

In order to achieve the above object, a fixed packing for armored cable according to the present invention comprises a tubular fastening metal fitting having a tubular packing inside and a tubular metal fitting body or an intermediate fitting. A fixed packing for an armored cable used for a cable fixing metal fitting that presses the outer peripheral surface of the armored cable that is inserted by the expanded output of the packing by screwing together with the A grounding part composed of a number of metal pieces, a waterproof part having a thick peripheral wall in the central part, and a clamp part composed of an arbitrary number of elastic claw pieces at the base end, To do.

Further, in the fixed packing for armored cable of the present invention, the outer periphery of the tip end portion of the packing main body is formed into a taper portion, the outer end portion is made to follow this taper portion, and the inner end portion is made of the thick wall of the packing. A grounding part having an arbitrary number of metal pieces bent along the inner peripheral wall provided at the tip of the packing body, and a waterproof part having a thick central wall at the center of the packing,
It is characterized in that it has a ring body provided with an arbitrary number of elastic claw pieces having a taper portion formed at the outer end portion and a clamp portion provided at the base end portion of the packing main body, and the waterproof portion thereof is fixed. The packing is characterized by being made of natural or synthetic rubber. Further, it is preferable that the ring body of the clamp part is made of a flexible synthetic resin, and the ring body of the clamp part is fixedly or detachably attached to the base end part of the packing body. be able to.

[0011]

According to the present invention, the fix packing is arranged in the insertion portion of the cover which constitutes the cable fixing metal fitting, the armored cable is inserted into the tubular hole of the fix packing, and the metal fitting body is covered or inserted through the screw portion. When screwed in with the intermediate metal fitting interposed, the grounding portion of the fix packing comes into pressure contact with the metal tubular portion of the armored cable, the waterproof portion comes into pressure contact with the inner peripheral wall of the fastening metal fitting, and the clamp portion comes into pressure contact with the armored cable covering portion. Grounding function, waterproof function,
A clamp function to prevent slipping out can be secured.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of a fixed packing for armored cable of the present invention, FIG. 2 is a side view of the same half cut, and FIG. 3 is a rear view of the same.

The fix packing 30 has a ground portion 31 on the tip side, a waterproof portion 32 on the middle portion, and a clamp portion 33 on the base end side. That is, the grounding part 31 and the waterproof part 3
2 is configured in a packing main body 34 made of a tubular rubber, and the clamp portion 33 is configured in a ring body 35 made of a tubular flexible synthetic resin.

In the packing body 34, a cylindrical hole portion 36 having a small diameter on the front end side and a cylindrical hole portion 37 having a large diameter on the base end side are communicated with each other, and a tapered portion 38 is formed on the outer periphery of the distal end portion. A plurality of metal pieces 39, 39, ...
Is provided. The metal piece 39 is formed by bending a metal plate made of copper having good conductivity into a substantially U-shape, and the outer end portion 4 thereof is formed.
0 is along the taper portion 38, and the inner end portion 41 is along the inner peripheral wall 42 of the cylindrical hole portion 36 of the packing body 34 and is fixed by an adhesive or the like, and is fixed in the circumferential direction of the tip portion of the packing body 34. A plurality of them, three in the illustrated example, are provided at intervals.

At the base end of the packing body 34, there is provided a fastening ring body 35 made of a flexible synthetic resin which constitutes the above-mentioned clamp portion 33. In this ring body 35, a base portion 44 of a plurality of claw pieces 43, 43, ... Which can press the outer periphery of the armored cable in a pressure contact state has a step portion 4 of the packing body 34.
Although it is attached integrally with 5, it may be attached detachably. A tapered portion 46 is formed on the outer end portion of the claw piece 43.

FIGS. 4 to 9 show first to fifth types of cable fixing metal fittings as examples of use of the fix packing 30 of the present invention. First type fixing bracket 51 of FIG.
Is configured such that the female screw portion 55 of the tubular metal cover 54 is screwed into the male screw portion 53 of the tubular metal fitting body 52.
The fix packing 30 is arranged in the insertion portion of the metal fitting body 52 and the cover 54, and the armored cable 50 is inserted and fixed in these cylindrical hole portions.

In this cable fixing bracket 51,
When the female screw portions 53 and 55 are screwed in, the taper portion 46 of the claw piece 43 of the ring body 35 is pushed by the taper portion 56 of the cover 54, and the taper portion 38 of the tip portion of the fix packing 30 and the outer end portion of the metal piece 39. 40 is pressed against the tapered inner peripheral wall 57 of the metal fitting body 52.

At this time, the inner end portion 41 of the metal piece 39 comes into contact with the metal tubular portion 59 leaking from the coating portion 58 of the armored cable 50, and the coating portion 58 is brought into close contact with the tubular hole portion 37 of the packing body 34. . Then, the weak current leaking from the covering portion 58 is appropriately passed by a device (not shown) to which the metal fitting body 52 is fixed, via the metal piece 39 of the grounding portion 31 that is in contact with the metal tubular portion 59 and the metal fitting body 52. Grounded. Also,
The thick peripheral wall 47 of the waterproof portion 32 comes into pressure contact with the inner peripheral wall 48 of the cover 54, and the waterproof property thereof is ensured. Similarly, each of the claw pieces 43 of the clamp portion 33 presses the armored cable 50 in a pressure-contact manner, and the retaining thereof is prevented. As described above, in the first-type fixing metal fitting 51, the grounding portion 31 of the fix packing 30 is pressed against the inner peripheral wall of the fixing metal fitting 51 at the three points of the waterproof portion 32 and the clamp portion 33.
Demonstrate two functions.

The second type of cable fixing bracket 63 shown in FIG.
Then, the metal fitting body 64 is the cable fixing metal fitting 5 of the first type.
It is configured to be longer in the axial direction than the metal fitting body 52 of 1.
A long packing 65 is arranged in the metal fitting body 64.
In addition, the fix packing 30 is arranged with a gland 67 interposed in a cover 66 that is similarly elongated in the axial direction. An earth tag 69, which is made of a highly conductive rectangular metal such as copper and has a spring property, is interposed in the tip recess 68 of the ground 67, as shown in FIG.

Also in the second type cable fixing fitting 63, the cover 66 is provided via the male and female screw portions 53 and 55.
When the screw is screwed into the metal fitting body 64, the taper portion 46 of the ring body 35 is pushed by the taper portion 56 of the cover 66, and the taper portion 38 of the tip portion of the fix packing 30 and the outer end portion 40 of the metal piece 39 are attached to the metal fitting body 64. It is grounded by being pressed into contact with the taper inner peripheral wall 48 of. Further, the waterproof property and the prevention of retaining are basically the same as those of the first type, and the taper portion 69 of the packing 65, the ground portion 31, the waterproof portion 32, and the clamp portion 33 are fixed to the fixing metal fitting 63 at four points. It is closely attached to the inner wall.

A third type of cable fixing bracket 72 of FIG.
Then, the male screw portion 76 of the intermediate metal fitting 75 is screwed into the female screw portion 74 of the metal fitting body 73, and the male screw portion 55 of the cover 54 is further screwed into the female screw portion 77 of the other end of the intermediate metal fitting 75 to be connected. The packing 78 is arranged in the metal fitting body 73, the gland 79 is arranged in the intermediate fitting 75, and the fix packing 30 is arranged in the cover 54. An O-ring 80 is provided in the recess 81 of the ground 79.

Also in the third type cable fixing metal fitting 72, the metal fitting main body 7 is inserted through the threaded portions 74, 76 ,.
3. When the intermediate metal fitting 75 and the cover 54 are connected, the taper portion 46 of the ring body 35 is pushed by the taper portion 56 of the cover 54, and the taper portion 38 at the tip of the fix packing 30 and the taper inner peripheral wall of the intermediate metal fitting 75. It is pressed against 82. The waterproofness and the prevention of retaining are similar to those of the first and second types, and the four points of the taper portion 83, the ground portion 31, the waterproof portion 32, and the clamp portion 33 of the packing 78 are included in the fixing metal fitting 72. It is closely attached to the surrounding wall.

A fourth type cable fixing bracket 85 of FIG.
Since the metal fitting body 86 is slightly different from the third-type metal fitting body 73 and the packing 87 is different, the other structure is the same as that of the third-type cable fixing metal fitting 72, and therefore the description thereof is omitted. There is.

The fourth type of cable fixing bracket 85 is substantially the same as the third type, and its waterproof property, prevention of retaining and grounding property can be secured.

A fifth type cable fixing bracket 90 shown in FIG.
Is substantially the same as the second type fixing fitting 63, and the ground lug 69 of FIG. 6 is arranged in the recess 92 at the tip of the gland 91.

[0026]

As described above, the fixed packing for armored cable used for the cable fixing metal fitting of the present invention is provided with the ground portion at the packing tip, the waterproof portion at the middle portion and the clamp portion at the base end portion. , The grounding part used for the cable fixing metal fitting, which is constructed by interposing a cover or an intermediate metal fitting on the metal fitting body, comes into pressure contact with the metal tubular part of the armored cable, and the waterproof part comes into pressure contact with the covering part of the cable. Also, the waterproof function, the clamp function of preventing the retaining function, and the grounding function can be ensured by pressing the clamp portion against the outer peripheral surface of the coating portion of the cable. Therefore, the unfixed fix packing for armored cable can be configured with a single member, and can secure three functions in a narrow range, the number of parts is small, the configuration is simple, and the manufacturing cost is low. It is easy to handle and can be easily and quickly incorporated into various types of cable fixing brackets.

[Brief description of drawings]

FIG. 1 is a front view of a packing for armored cable of the present invention.

FIG. 2 is a side view of the same half-cutting machine.

FIG. 3 is a rear view of the same.

FIG. 4 is a half-cut side view of a first type cable fixing metal fitting using the packing of the present invention.

FIG. 5 is a half-cut side view of the second type cable fixing bracket.

FIG. 6 is a perspective view of an earth tag.

FIG. 7 is a half-cut side view of the third type cable fixing bracket.

FIG. 8 is a half-cut side view of the fourth type cable fixing bracket.

FIG. 9 is a half-cut side view of the fifth type cable fixing bracket.

FIG. 10 is a half-cut side view of a conventional cable fixing bracket.

FIG. 11 is a half-cut side view of a conventional elastic body.

[Explanation of symbols]

 30 Fix Packing 31 Grounding Part 32 Waterproof Part 33 Clamping Part 34 Packing Body 38 Tapered Part 39 Metal Piece 43 Claw Piece 47 Thick Wall

Claims (5)

[Claims] 1. An armored product in which a tubular fastening metal fitting having a tubular packing inside and a tubular metal fitting main body or an intermediate metal fitting are screwed together by a screw portion and inserted by the expansion output of the packing. This is a fixed packing for armored cables that is used as a cable fixing metal fitting that presses the outer peripheral surface of the cable.This fixed packing has a grounding part consisting of an arbitrary number of metal pieces at the tip and a waterproof structure with a thick wall around the center. A fixed packing for an armored cable, characterized in that the fixed packing is provided with a portion and a clamp portion composed of an arbitrary number of elastic claw pieces at a base end portion. 2. An arbitrary outer periphery of the packing main body is formed into a taper portion, the outer end portion is provided along the taper portion, and the inner end portion is bent along the inner peripheral wall of the thick peripheral wall of the packing. A grounding part with a number of metal pieces at the tip of the packing body, a waterproof part with a thick peripheral wall at the center of the packing, and an arbitrary number of elastic claw pieces with a tapered part at the outer end are provided. A fixed packing for an armored cable, which is provided with a clamp portion in which a ring body is provided at a base end portion of a packing main body. 3. The fix packing for an armored cable according to claim 1 or 2, wherein the fix packing of the waterproof part is made of natural or synthetic rubber. 4. The fix packing for an armored cable according to claim 1, wherein the ring body of the clamp portion is made of a flexible synthetic resin. 5. The fixed packing for armored cable according to claim 1, wherein the ring body of the clamp part is fixedly or detachably attached to the rear end of the packing body.