KR101697208B1 - Junction box with internal cable grand and explosion proof lighting having the same - Google Patents

Abstract

According to the present invention, disclosed are a cable grand-embedded junction box and an explosion-proof lamp including having the same. The cable grand-embedded junction box is used in the explosion-proof lamp, and comprises: a first housing used for an explosion-proof lamp, and having an insertion hole into which an external power line is inserted; a second housing forming a sealed space with the first housing, wherein an internal power line is inserted into the second housing; and a cable grand inserted into a combination hole inside the insertion hole on a sealed space side to prevent moisture from penetrating between the first housing and the external power line. According to the present invention, the costs required by the cable grand in the explosion-proof lamp is lowered while a steady and firm explosion-proof structure is provided, occurrence of interference between structures or installations in an explosion-proof area due to the cable grand is removed, and a simple installation structure is provided.

Description

{JUNCTION BOX WITH INTERNAL CABLE GRAND AND EXPLOSION PROOF LIGHTING HAVING THE SAME}

The present invention relates to a cable gland built-in junction box and explosion-proof box including the same, and more particularly, to a cable gland built-in junction box which is provided to provide a solid explosion-proof structure while reducing the cost of a cable gland in explosion- And an explosion-proof structure including the same.

Equipment used to prevent explosion. In factories that handle petrochemical, thermal power, and pharmaceuticals, there are those that have built explosion-proof technologies in switches, lighting facilities, and liquid level gauges, and these are called explosion-proof devices.

Explosion-proof, etc. are applied to explosion-proof chemical plants, liquefied natural gas (LPG) charging stations, mine tunnels, nuclear power plants, etc., which are explosion-proof due to dust and steam or gas. It says.

The cable grand is used to provide waterproof, flameproof and explosion-proof structure for the cable connection position of the junction box when connecting the external power line to the junction box. The cable gland used in explosion-proof facilities must be individually explosion-proof certified, so the purchase cost is relatively high due to the certification fee.

In this connection, Korean Patent Publication No. 1304258 discloses an explosion-proof cable gland structure, Patent Publication No. 861686 discloses an explosion-proof multi-core cable gland, and Patent Publication No. 1608174 discloses an explosion- Paul Union cable gland is disclosed.

The cable glands disclosed in the registered patent publications No. 1304258, No. 861686 and No. 1608174 have a slightly different detailed structure depending on the type, but the basic installation procedure is as follows. First, disassemble the configuration of the cable gland, fasten the body to the junction box, and then fasten the nipple to the external power line. Then insert the packing and washer into the body and insert the external power line into the packing. After that, the joints and the cables are tightened using the joint bushing, and then the body and the nipple are assembled.

However, since the cable glands disclosed in the registered patent publications 1304258, 861686 and 1608174 are installed in a structure protruding outward from the cable connection position of the junction box, they are installed in the explosion district The cable gland protruding from the junction box often interferes with the structure or the installation of the explosion-proof area, so that it is difficult to install the cable gland in an appropriate position.

As described above, the basic installation procedure of the cable gland involves seven stages of complicated installation sequence such as cable gland disassembly, body fastening, nipple fastening, packing and washer insertion, external power line insertion, joint bushing fastening, body and nipple assembly The cable gland disclosed in the registered patent publications 1304258, 861686 and 1608174 proposes a more complicated installation procedure, but the complicated installation step is liable to cause a mistake by the operator, Cable glands having a simple installation structure are more preferred in the field.

(0001) Korean Patent Registration No. 1304258 (Registered on March 31, 2013) (0002) Korean Patent Registration No. 861686 (Registered on September 29, 2008) (0003) Korean Patent Publication No. 1608174 (Registered on Feb. 25, 2016)

SUMMARY OF THE INVENTION An object of the present invention is to provide a cable gland built-in type that can provide a solid explosion-proof structure while lowering the cost of the cable gland in explosion-proof or the like, solving the occurrence of interference with structures and fixtures in explosion-proof areas by cable glands, A junction box, and an explosion proof having the same.

According to the present invention, the above object can be accomplished by providing a first housing which is used for explosion-proofing or the like and has an insertion hole into which an external power line is inserted; A second housing which forms an enclosed space together with the first housing and into which an internal power line is inserted; And a cable gland inserted in the coupling hole inside the insertion hole to block the passage of moisture through the space between the first housing and the external power line.

The cable gland comprising: a packing inserted in the coupling hole; And a bushing screwed into the coupling hole so as to press the packing so that the inner circumferential surface of the packing is in close contact with the outer circumferential surface of the external power source line.

Wherein the packing has an inclined surface with an outer diameter decreasing toward the insertion hole at an end of the insertion hole, wherein the coupling hole includes: a first coupling hole in which the inclined surface is closely contacted; And a second engagement hole having the bushing threaded and having an outer diameter larger than that of the first engagement hole.

Wherein the external power line and the protruding portion are formed on the inner circumferential surface of the packing so that the external power line and the protruding portion are in close contact with the external power line by the step between the inner circumferential surface of the packing and the protruding portion, So that an isolated space surrounded by the packing can be formed.

A water absorbent body for absorbing moisture permeating the isolation space may be attached to the inner circumferential surface of the packing between the inner circumferential surface of the packing and the protruding portion which are in close contact with the external power supply line.

Wherein the cable gland includes a washer interposed between the bushing and the packing and the washer and the packing form a contact surface spaced apart from the screwing shaft of the bushing toward the insertion hole, The washer may slide on the contact surface and the packing may be deformed toward the external power line.

Wherein the cable gland comprises a washer interposed between the bushing and the packing, the washer comprising: a first body in contact with the packing; A second body in contact with the bushing; And an elastic member interposed between the first body and the second body, wherein the elastic member compresses the packing by self-elastic recovery force after the bushing is screwed into the fitting hole Lt; / RTI >

According to the present invention, said object is achieved by a cable gland built-in junction box; A converter electrically connected to the junction box by a power line; And an explosion-proof built-in cable gland including a body provided with a lamp for receiving light converted from the converter and emitting light.

According to the present invention, the cable gland is inserted into the coupling hole inside the insertion hole at the sealed space side to block the passage of moisture through the space between the first housing and the external power line, thereby providing a solid explosion proof structure, It is possible to provide a cable gland built-in junction box and an explosion-proof box having the same, which can reduce costs and solve the occurrence of interference with a structure or installation of an explosion-proof area by a cable gland and provide a simple installation structure.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view of an explosion-proof lamp with built-in cable glands of the present invention; Fig.
Fig. 2 is an exploded perspective view of the explosion-proof lamp built in the cable gland of Fig. 1; Fig.
3 to 5 are cross-sectional views illustrating a process of installing a cable gland in a cable gland built-in junction box of the present invention.
6 to 8 are partial sectional views showing various embodiments of a cable gland in a cable gland built-in junction box of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, the well-known functions or constructions are not described in order to simplify the gist of the present invention.

The cable gland built-in junction box of the present invention and the explosion-proof box having the same provide a solid explosion-proof structure while lowering the cost of the cable gland in explosion-proof or the like, solving the interference with structures or fixtures in the explosion- Installation structure is provided.

FIG. 1 is a perspective view of an explosion-proof lamp with a built-in cable gland of the present invention, FIG. 2 is an exploded perspective view of an explosion- 6 to 8 are partial sectional views showing various embodiments of a cable gland in a cable gland built-in junction box of the present invention. Fig.

As shown in FIGS. 1 and 2, the present invention provides a cable gland built-in type explosion-proof lamp 1 that provides a solid explosion-proof structure while reducing the cost of the cable gland 300 in explosion-proof lamps 1, And includes a body 10, a converter 20, and a junction box 30. [

The body 10 provided with a lamp (not shown) for emitting light and the converter 20 for converting the electric power supplied to the body 10 have a general explosion-proof configuration and the like so that the details of the body 10 and the converter 20 A detailed description of the configuration will be omitted.

1 and 2, the junction box 30 has a structure for interconnecting the external power line W1 and the internal power line W2 and includes a first housing 100, a second housing 200 And a cable gland (300). In order to facilitate understanding, the upper and lower portions will be described below in the state shown in the drawings.

2 and 5, the first housing 100 and the second housing 200 together form a closed space A, and the first housing 100 and the second housing 200 may have the same structure as the first housing 100 and the second housing 200, Are engaged by the bolts (B) in a state in which the O-rings (R) are interposed. 5, the state in which the external power line W1 and the internal power line W2 are connected to each other in the closed space A is not shown for easy understanding of the cable gland 300 as a main feature of the present invention.

3 and 4, an insertion hole 101 into which the external power line W1 is inserted is formed at the upper end of the first housing 100, a coupling hole 102 is formed inside the insertion hole 101, .

The coupling hole 102 is configured to include a first coupling hole 102A for guiding movement and deformation of the packing 310 and a second coupling hole 102B to which the bushing 320 is screwed. The first engaging hole 102A is formed on the side of the insertion hole 101 with respect to the second engaging hole 102B and the second engaging hole 102B is formed with an outer diameter larger than that of the first engaging hole 102A. On the inner circumferential surface of the second engagement hole 102B, a thread is formed in which the bushing 320 is screwed.

5, a hole through which the internal power line W2 is inserted is formed in the lower end of the second housing 200, and a hole is formed in the hole to connect the converter 20 and the junction box 30 to each other. (N) and the seal packing (P) are combined. The connector N and the seal packing P are applicable to a variety of known techniques for mechanically connecting the converter 20 and the junction box 30 in addition to the structure shown in the drawings.

The cable gland 300 is inserted into the coupling hole 102 inside the insertion hole 101 to block the passage of moisture through the space between the first housing 100 and the external power line W1. , A bushing (320), and a washer (330).

3 to 5, the packing 310 elastically deforms to block the gap between the first housing 100 and the external power line W1. The first housing 100 and the second housing 100 200) are inserted into the first coupling hole 102A (see Fig. 3) while being separated from each other. The lower end of the packing 310 protrudes in the form of a ring and is inserted into the washer 330.

2 and 3, an inclined surface 311 having an outer diameter decreasing toward the insertion hole 101 is formed at the end of the packing 310 on the side of the insertion hole 101. [ The inclined surface 311 is in close contact with the inclined portion 110 of the first engaging hole 102A (with the packing 310 inserted into the first engaging hole 102A). The inclined portion 110 provides an inclined guide surface for elastically deforming the packing 310 toward the external power supply line W1.

4, after the packing 310 is inserted into the first engaging hole 102A, the washer 330 is fitted to the lower end of the packing 310. As shown in Fig. The washer 330 is formed in a ring shape and interposed between the bushing 320 and the packing 310 to prevent deformation of the packing 310 due to the rotational force of the bushing 320.

The external power line W1 is inserted into the insertion hole 101 and the coupling hole 102 through the packing 310 after the washer 330 is fitted to the lower end of the packing 310. [ The bushing 320 is then screwed into the second engagement hole 102B.

4 and 5, the bushing 320 is configured to press the packing 310 while being screwed to the second engaging hole 102B. The upper surface of the packing 310 is in close contact with the lower end surface of the washer 330 And presses the packing 310 upward. The inner space of the packing 310, the washer 330, and the bushing 320 will be referred to as a power line through hole 301 for easy understanding.

At the lower end of the bushing 320, a step 321 is formed at the lower end of the second coupling hole 102B to engage with the first housing 100. The bushing 320 is finished to be screwed to the second engaging hole 102B in a state in which the stepped portion 321 is in close contact with the first housing 100 (see Fig. 5).

4 shows a state in which the upper end surface of the bushing 320 first contacts the lower end surface of the washer 330. Figure 5 shows a state in which the step 321 is engaged with the first housing 100, The state where the threaded engagement of the bushing 320 is completed is shown.

The packing 310 is elastically deformed by the pressure of the bushing 320 during the process of screwing the bushing 320 from the state shown in FIG. 4 to the state shown in FIG. 5 to form a gap between the first housing 100 and the external power line W1 Lt; / RTI >

4, the rotational force of the bushing 320 is not transmitted to the packing 310 by the washer 330, but the rotational force of the bushing 320 in the rotational axis direction is not transmitted to the packing 310, Lt; / RTI > The packing 310 is elastically deformed toward the external power supply line W1 while being slid in a state in which the inclined face 311 is in close contact with the inclined portion 110 by the urging force of the bushing 320. [

5, when the screwing of the bushing 320 is completed, the upper portion of the packing 310 is elastically deformed such that its inner peripheral surface is tightly adhered to the outer peripheral surface of the external power line W1. In this state, the insertion hole 101 and the power supply line passage hole 301 are isolated from each other by the elastic deformation of the packing 310, so that the sealed space A inside the junction box 30 is inserted into the insertion hole 101, So that the inflow of external moisture is securely prevented.

After the external power line W1 and the internal power line W2 are connected to each other, the bolts B are fastened through the through holes H1 and the screw holes H2 to connect the first housing 100 and the second housing 200).

Conventional cable glands used in explosion-proof facilities require individual explosion-proof certification, so the purchase cost is relatively high due to the certification fee.

In addition, since the conventional cable gland is installed with a structure protruding outward from the cable connection position of the junction box, the cable gland protruding from the junction box when installed in the explosion district may interfere with the structure or the installation of the explosion- It often happens that it is difficult to install in a location.

In addition, the basic installation procedure of the cable gland follows a somewhat complicated installation sequence of 7 steps such as cable gland disassembly, body fastening, nipple fastening, packing and washer insertion, external power line insertion, joint bushing fastening, body and nipple assembly, Although the cable gland disclosed in Patent Publications 1304258, 861686 and 1608174 suggests a more complicated installation process, the complicated installation steps are liable to cause an operator's mistake and are expensive, A cable gland having a simple installation structure is more preferable.

The cable gland built-in junction box 30 of the present invention and the explosion-proof lamp 1 having the same have the individual explosion-proof certification of the cable gland 300 as the cable gland 300 is embedded in the junction box 30 There is an advantage in that the interference between the cable gland 300 and the structure or installation of the explosion-proof area is prevented.

The cable gland built-in junction box 30 of the present invention can be manufactured by disassembling the cable gland 300, inserting the packing 310 and the washer 330, W1) insertion, and bushing 320 fastening. Therefore, there is an advantage in that manufacturing can be reduced due to the reduction of parts and a worker's mistake can be reduced.

6, a protrusion 312 may be formed on the inner peripheral surface of the packing 310 so as to be in close contact with the external power line W1. The projecting portion 312 is formed in a shape in which an arcuate cross section protruding from the inner peripheral surface of the packing 310 toward the external power supply line W1 is continuous along the circumferential direction about the threaded axis of the bushing 320. The shortest inner diameter of the protruding portion 312 may be formed smaller or larger than the outer diameter of the external power line W1.

6B, when the bushing 320 is completely screwed, the upper part of the packing 310 is elastically deformed so that the inner peripheral surface of the upper part of the packing 310 is tightly adhered to the outer peripheral surface of the external power line W1 The protruding portion 312 is pressed by the inclined portion 110 to be in close contact with the outer peripheral surface of the external power line W1 and the inner peripheral surface of the packing 310 closely attached to the external power line W1, An isolation space S surrounded by the external power line W1 and the packing 310 is formed between the inner peripheral surface of the packing 310 and the protruding portion 312. [

A water absorbent body 313 for absorbing moisture permeating the isolation space S is attached to the inner circumferential surface of the packing 310 between the inner peripheral surface of the packing 310 and the protruding part 312 closely attached to the external power line W1 . Therefore, even if moisture permeates into the isolation space S, the moisture absorbed by the moisture absorption body 313 is immediately absorbed and moisture is prevented from moving beyond the isolation space S.

The water absorbent 313 may be made of a super absorbent polymer or the like. The superabsorbent resin is a synthetic polymer material having a function of absorbing pure water of 500-1000 times its own weight. When absorbed water, it rapidly changes into a gel state. After the change into a gel state, . The superabsorbent resin is a known technique and a detailed description thereof will be omitted.

7, the washer 330 and the packing 310 may form a contact surface spaced apart from the threaded shaft of the bushing 320 toward the insertion hole 101. As shown in FIG.

For ease of understanding, the contact surface formed in the washer 330 is referred to as an oblique contact surface 302, and the contact surface formed in the packing 310 is referred to as an oblique end surface 314. [ The inclined contact surface 302 is formed between the inner circumferential surface and the upper surface of the washer 330 and the inclined end surface 314 is formed above the annular protruding portion of the packing 310.

As shown in Fig. 7 (a), the lower end portion of the packing 310 is fitted in the washer 330 to form an inclined contact surface of the inclined contact surface 302 and the inclined end surface 314.

7 (b), when the bushing 320 is screwed into the second coupling hole 102B, the upper portion of the packing 310 is firmly adhered to the outer peripheral surface of the external power line W1 And the inclined contact surface 302 of the washer slips at an inclined end face 314 of the packing 310 so that the lower part of the packing 310 is elastically deformed toward the external power supply line W1.

The area of the packing 310 that is in contact with the outer peripheral surface of the external power supply line W1 from the upper portion of the packing 310 is expanded to the lower portion of the packing 310 as the lower portion of the packing 310 is elastically deformed toward the external power supply line W1 as a whole, There is an advantage that the sealing structure between the external power line 310 and the external power line W1 is strengthened.

8, the washer 330 may include a first body 331, a second body 332, and an elastic member 333.

8 (a), the upper surface of the first body 331 is in contact with the packing 310, and the lower surface of the second body 332 is in contact with the bushing 320. The first body 331 and the second body 332 are respectively opened in a direction facing each other and a space is formed between the first body 331 and the second body 332 while the second body 332 is inserted into the first body 331 .

An elastic member 333 is interposed in a space between the first body 331 and the second body 332. The elastic member 333 is provided with a plurality of compression springs to form an elastic recovery force that separates the first body 331 and the second body 332 from each other when the first body 331 and the second body 332 approach each other.

8 (b), when the bushing 320 is screwed into the second coupling hole 102B, the upper portion of the packing 310 is firmly adhered to the outer peripheral surface of the external power line W1 And at the same time, the first body 331 and the second body 332 are brought close to each other, and the elastic member 333 is elastically compressed.

The elastic member 333 is elastically compressed between the first body 331 and the second body 332 and continuously pressurizes the packing 310 due to its own elastic restoring force so that the inner peripheral surface of the packing 310 There is an advantage that the form adhered to the outer peripheral surface of the external power line W1 is firmly held.

According to the present invention, the cable gland is inserted into the coupling hole inside the insertion hole at the sealed space side to block the passage of moisture through the space between the first housing and the external power line, thereby providing a solid explosion proof structure, It is possible to provide a cable gland built-in junction box and an explosion-proof box having the same, which can reduce costs and solve the occurrence of interference with a structure or installation of an explosion-proof area by a cable gland and provide a simple installation structure.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It is obvious to those who have. Accordingly, it should be understood that such modifications or alterations should not be understood individually from the technical spirit and viewpoint of the present invention, and that modified embodiments fall within the scope of the claims of the present invention.

1: explosion-proof light
10: body 20: converter
N: Connector P: Packing
W1: External power line W2: Internal power line
30: junction box
300: Cable Grand
310: packing 100: first housing
311: Slope surface 101: Insertion hole
312: protrusion 102: engaging hole
313: Water Absorption Body 102A: First engagement hole
314: inclined end face 102B: second engaging hole
320: bushing 110:
321: step 200: second housing
330: Washer A: Sealed space
331: First body R: O-ring
332: second body H1: through hole
333: Elastic member H2: Screw hole
301: Power line through hole B: Bolt
302: inclined contact surface

Claims (8)

A first housing used for explosion-proofing or the like and having an insertion hole into which an external power line is inserted; A second housing which forms an enclosed space together with the first housing and into which an internal power line is inserted; And a cable gland inserted in the coupling hole inside the insertion hole to block passage of moisture through the space between the first housing and the external power line,
The cable gland comprising: a packing inserted in the coupling hole; And a bushing screwed into the coupling hole to press the packing so that the inner circumferential surface of the packing is in close contact with the outer circumferential surface of the external power source line,
A protruding portion that is in close contact with the external power line is formed on an inner peripheral surface of the packing,
Wherein an outer space surrounded by the external power line and the packing is formed between the inner circumferential surface of the packing and the protruding portion in close contact with the external power line by the step between the inner circumferential surface of the packing and the protruding portion, box. delete The method according to claim 1,
And an inclined surface having an outer diameter decreasing toward the insertion hole is formed at an end of the packing at the insertion hole side,
The coupling hole
A first engaging hole to which the inclined surface is closely attached; And
Wherein the bushing is threaded and includes a second coupling hole having an outer diameter larger than that of the first coupling hole. delete The method according to claim 1,
Wherein a water absorbent body for absorbing moisture permeated into the isolation space is attached to an inner circumferential surface of the packing between the inner circumferential surface of the packing and the protruding portion which are in close contact with the external power supply line. The method according to claim 1,
Wherein the cable gland includes a washer interposed between the bushing and the packing,
Wherein the washer and the packing form a contact surface spaced apart from the threaded shaft of the bushing toward the insertion hole,
Wherein the washer is slid on the contact surface in a process of screwing the bushing into the coupling hole, and the packing is deformed toward the external power line. The method according to claim 1,
Wherein the cable gland includes a washer interposed between the bushing and the packing,
The washer
A first body in contact with the packing;
A second body in contact with the bushing; And
And an elastic member interposed between the first body and the second body,
Wherein the elastic member presses the packing by a self-elastic recovery force after the bushing is compressed in the process of screwing the bushing into the coupling hole. A cable gland built-in junction box according to claim 1;
A converter electrically connected to the junction box by a power line; And
A cable gland built-in type explosion-proof lamp including a body provided with a lamp that receives the converted power from the converter and emits light.

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