Explosion-proof motor junction box structure, wiring arrangement and trepanning method

Abstract

The invention provides an explosion-proof motor junction box structure, a junction box is in an irregular trapezoid box shape, and comprises a first junction box cover, a junction box main body, a wiring board and a second junction box cover, a closed area enclosed by the first junction box cover, the junction box main body and the second junction box cover is a cavity, the wiring board is arranged in the junction box, and the junction box main body and the second junction box cover are arranged in the cavity. A low-voltage wiring terminal and a main wiring column are installed on the wiring board, the first junction box cover and the second junction box cover are fixed to the upper portion and the side portion of the junction box respectively, and an arc-shaped installation hole is formed in the position, corresponding to the second junction box cover, of the junction box body. The arrangement method and the trepanning method of the wiring terminals and the binding posts in the explosion-proof motor junction box provided by the invention are combined. The height of the junction box is reduced by reducing the size and height of the hole in the middle of the junction box and matching with the shape change of the hole, and the junction box is suitable for places with high requirements for the height of a motor.

Description

Technical Field

[0001] The present invention relates to the technical field of motor junction boxes, and in particular to an explosion-proof motor junction box structure, a wiring arrangement and a hole opening method. Background Art

[0002] Coal mining mainly includes open-pit coal mining and underground coal mining. Due to the closed space of underground coal mines, the air is often mixed with a certain amount of methane gas. At the same time, the space size of coal mines is relatively limited, especially in the working face of coal mining, the space is even more tight, which puts strict requirements on the size of the equipment used.

[0003] Most of the motor equipment in coal mines is structured in accordance with GB / T 3836.2 flameproof type. This explosion-proof type requires that the shortest path from the inside of the motor to the outside through the joint surface must be greater than a certain length, which mainly puts forward requirements on the joint surface of the motor housing structure. There are mainly two types of joint types: the stopper flameproof surface and the plane flameproof surface. There are three key points: joint gap, joint length and joint surface roughness. The joint length will affect the size of the motor to a certain extent, which is particularly obvious in small motors.

[0004] In terms of electrical, the creepage distance and electrical clearance requirements in GB / T 3836.3 must be implemented, which mainly affects the size of the junction box and the layout of related electrical components in the junction box. The limited space of the underground working environment of coal mines has strict restrictions on the length, width and height of the motor. Since the length and width are often determined by electromagnetic properties and are generally not easy to reduce, there are certain requirements for the installation height of the junction box during use.

[0005] In summary, due to the special requirements of the working environment in coal mines, the design of the junction box for explosion-proof motors is an important link. Figure 1-2 As shown, the junction box is square or round, and the main terminals and low-voltage terminals in the junction box are arranged in a vertical direction; the opening of the junction box is square (flat flameproof) or round (flat flameproof or stopper flameproof), and is located directly above; the low-voltage terminals are two-way clamping type. However, the height of the junction box is greatly affected by the height of the main terminals. The main terminals and low-voltage terminals are standard parts with relevant certifications, and the sizes are generally fixed, so the minimum height of the junction box is equal to the height of the main terminals plus the electrical clearance plus the thickness of the junction box cover; when the opening of the mounting hole is round, the flameproof surface can adopt two flameproof types: stopper or plane; when the opening of the mounting hole is square, the flameproof surface mostly adopts a plane flameproof type. Since it is difficult to ensure the gap during the processing of the square stopper and the measurement work is also difficult to carry out, the stopper flameproof type is generally not adopted. As shown Figure 3-4Another junction box structure of the prior art is shown, in which the junction box is square, and the main terminal blocks and low-voltage terminals in the junction box are arranged horizontally. With this wiring arrangement, the height of the junction box is mainly affected by the size of the opening and the length of the flameproof surface joint, while the size of the mounting hole is mainly determined by the low-voltage terminal with a larger appearance. Therefore, the above junction box structures cannot reasonably arrange the positions of the main terminal blocks and the low-voltage terminal blocks according to the internal structure of the junction box, thereby reducing the height of the junction box.

[0006] In view of this, the present invention proposes an explosion-proof motor junction box structure suitable for underground coal mines to overcome the defects of the prior art. Summary of the invention

[0007] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art. The present invention provides an explosion-proof motor junction box structure, wiring arrangement and hole opening method that can be used in coal mines, thereby further reducing the height of the explosion-proof motor junction box, thereby meeting the needs of places with high requirements on motor height.

[0008] In a first aspect, the present invention provides an explosion-proof motor junction box structure, wherein the junction box is an irregular trapezoidal box shape, comprising a first junction box cover, a junction box body, a junction board and a second junction box cover, wherein the enclosed area surrounded by the first junction box cover, the junction box body and the second junction box cover is a cavity, a junction board is arranged inside the junction box, and low-voltage terminals and main terminals are installed on the junction board, the first junction box cover and the second junction box cover are respectively fixed to the upper part and the side part of the junction box, and an arc-shaped mounting hole is opened on the junction box body corresponding to the second junction box cover.

[0009] Furthermore, the first junction box cover is planar.

[0010] Furthermore, the second junction box cover is planar.

[0011] Furthermore, the bottom of the junction box body is a curved surface, and the left and right side surfaces are symmetrically inclined surfaces, the upper ends of the two side surfaces are vertical planes, and the lower ends are inclined surfaces that tilt outward from top to bottom.

[0012] Furthermore, the vertical planes and the inclined planes on the two side surfaces of the junction box body are integrally connected.

[0013] Furthermore, the distance between any position on the mounting hole and the edge of the junction box should be no less than the minimum joint surface length.

[0014] Furthermore, the first junction box cover, the second junction box cover and the junction box body are fixedly connected by bolts.

[0015] In a second aspect, the present invention provides a method for arranging terminals and terminals in an explosion-proof motor junction box, based on the structure of the explosion-proof motor junction box, comprising the following steps:

[0016] First, determine the position of the low-voltage terminal. Draw a circle with the center of the low-voltage terminal as the center and the minimum distance of the electrical clearance required by the low-voltage terminal as the radius. Make the edge of the circle tangent to the edge of the junction box to determine the center of the low-voltage terminal, that is, the position of the low-voltage terminal.

[0017] Next, determine the position of the outermost main terminal. Draw a circle with the center of the main terminal as the center and the minimum distance of the electrical clearance required by the main terminal as the radius. Make the edge of the circle tangent to the edge of the junction box. Determine the center of the outermost main terminal, that is, the position of the outermost main terminal.

[0018] Finally, determine the positions of other main terminals, ensure that the circles drawn with the required minimum electrical clearance distance as the radius of adjacent main terminals are tangent to each other, and obtain the positions of other main terminals.

[0019] In a third aspect, the present invention provides a method for opening a hole in an explosion-proof motor junction box, based on the structure of the explosion-proof motor junction box, comprising the following steps:

[0020] When opening the mounting hole on the motor junction box, you need to first draw the opening circle corresponding to the position of the low-voltage terminal on the wire box, and then draw the opening circle corresponding to the position of the main terminal in turn. All the opening circles are used as inscribed circles, and the figure formed by connecting the tangents of the upper and lower vertices of the opening circle in the vertical direction is used as the shape of the mounting hole.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] The present invention reduces the height of the terminal box by reducing the opening size and height of the mounting hole in the middle of the terminal box and changing the shape of the opening, and is suitable for places with high requirements on the height of the motor. In addition, the arrangement of the terminal post and the low-voltage terminal in the present invention makes better use of the space in the terminal box structure, improves the shape of the rear opening of the terminal box while meeting the length of the flameproof surface joint surface, and makes the clamping low-voltage terminal easy to install. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a front structural schematic diagram of an explosion-proof motor junction box in the prior art;

[0024] Figure 2 It is a side cross-sectional structural schematic diagram of an explosion-proof motor junction box in the prior art;

[0025] Figure 3 It is a front structural schematic diagram of the explosion-proof motor junction box in the second prior art;

[0026] Figure 4 It is a side cross-sectional structural schematic diagram of the second explosion-proof motor junction box in the prior art;

[0027] Figure 5 It is a structural schematic diagram of the explosion-proof motor junction box of the present invention;

[0028] Figure 6 It is a structural schematic diagram of positioning the low-voltage terminal and the main terminal in the junction box of the present invention;

[0029] Figure 7 It is a front structural schematic diagram of the explosion-proof motor junction box of the present invention;

[0030] Figure 8 It is a schematic diagram of the side cross-sectional structure of the explosion-proof motor junction box of the present invention.

[0031] Among them, 1-first junction box cover; 2-junction box body; 3-terminal board; 4-second junction box cover; 5-low-voltage terminal; 6-main terminal; 7-mounting hole; C1-minimum distance circle of low-voltage terminal; C2-minimum distance circle of main terminal; d-electrical clearance; h-length of joint surface. DETAILED DESCRIPTION

[0032] The embodiments of the present invention will be described in detail below with reference to examples, but those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be construed as limiting the scope of the present invention.

[0033] According to an embodiment of the present invention, referring to the attached Figure 5-8 As shown, the present invention provides an explosion-proof motor junction box structure, the junction box is an irregular trapezoidal box, such as Figure 5 As shown. It includes a first junction box cover 1, a junction box body 2, a wiring board 3, a second junction box cover 4, a low-voltage terminal 5, a main terminal 6 and a mounting hole 7. The enclosed area surrounded by the first junction box cover 1, the junction box body 2 and the second junction box cover 4 is a cavity. The wiring board 3 is arranged inside the junction box, and the low-voltage terminal 5 and the main terminal 6 are installed on the wiring board 3. The first junction box cover 1 and the second junction box cover 4 are respectively fixed to the upper part and the side part of the junction box, and an arc-shaped mounting hole 7 is opened on the junction box body 2 corresponding to the second junction box cover 4.

[0034] According to the embodiment of the present invention, the first junction box cover 1 is planar and is bolted to the top of the junction box body 2. The second junction box cover 4 is planar and is bolted to one side of the junction box body 2 where the mounting hole 7 is provided.

[0035] According to an embodiment of the present invention, the bottom of the junction box body 2 is a curved surface, and the left and right side surfaces thereof are symmetrical inclined surfaces, the upper ends of the two side surfaces are vertical planes, and the lower ends are inclined surfaces inclined outward from top to bottom. The vertical plane and the inclined surface on any one of the two side surfaces of the junction box body 2 are integrally connected.

[0036] According to an embodiment of the present invention, the mounting hole 7 is provided on the junction box body 2, and any position on the mounting hole 7 should be no less than the minimum joint surface length h corresponding to the edge of the junction box, that is, the design of the mounting hole 7 needs to meet the minimum length requirement of the joint surface, and at the same time, when the hole is opened at the position facing the low-voltage terminal 5, the operating tool should be able to enter, and the remaining positions of the mounting hole 7 are changed according to the position of the main terminal 6.

[0037] The present invention provides a method for arranging wiring terminals and wiring posts in an explosion-proof motor junction box, comprising the following steps:

[0038] First, determine the position of the low-voltage terminal 5, draw a circle with the center of the low-voltage terminal 5 as the center and the minimum distance of the electrical clearance d required by the low-voltage terminal 5 as the radius, make the edge of the drawn circle contact and be tangent to the edge of the junction box, and determine the center of the low-voltage terminal 5, that is, the position of the low-voltage terminal 5.

[0039] Next, determine the position of the outermost main terminal 6, draw a circle with the center of the main terminal 6 as the center and the minimum distance of the electrical clearance d required by the main terminal 6 as the radius, make the edge of the circle contact and be tangent to the edge of the junction box, and determine the center of the outermost main terminal 6, that is, the position of the outermost main terminal 6.

[0040] Finally, the positions of other main terminals 6 are determined to ensure that the circles drawn with the minimum required electrical clearance d as the radius of adjacent main terminals 6 are tangent to each other, thereby obtaining the positions of other main terminals 6.

[0041] According to the embodiment of the present invention, the main terminal 6 and the low-voltage terminal 5 are arranged horizontally. The specific position is to draw a circle with the center of the part as the center and the minimum electrical clearance d required by each part as the radius. The circle edge is tangent to the edge of the junction box. The position of the lowest height of the junction box can be found by combining the positions of all parts. The design is as follows: Figure 6 As shown, after the various parts are tangent to each other, the minimum distance circle C1 corresponding to the low-voltage terminal 5 and the minimum distance circle C2 corresponding to the main terminal 6 are obtained.

[0042] According to the embodiment of the present invention, the minimum electrical clearance corresponding to each component can be obtained by checking the national standard according to the different voltage levels used.

[0043] According to an embodiment of the present invention, a method for opening a hole in an explosion-proof motor junction box provided by the present invention comprises the following steps:

[0044] When opening the mounting hole on the motor junction box, it is necessary to first draw the opening circle corresponding to the position of the low-voltage terminal 5 on the wire box, and then draw the opening circles corresponding to the position of the main terminal 6 in sequence. All the opening circles are used as inscribed circles, and the figure formed by connecting the tangents of the upper and lower vertices of the opening circles in the vertical direction is used as the shape of the mounting hole 7.

[0045] According to the embodiment of the present invention, when opening a hole in the junction box, a circle is first drawn at the corresponding position of the low-voltage terminal 5, and the size of the circle should leave an operable space. Then, the opening pattern of the main terminal 6 is drawn, and the shape changes according to the arrangement position. After completion, the patterns are connected together, and this shape is the shape and size of the installation hole 7, which also corresponds to the shape and size of the minimum opening.

[0046] With the shape of the mounting hole 7 as the edge, the required joint surface length h is offset outward, and the closed space formed by the offset pattern and the edge of the opening is the position of the joint surface. The bolts are arranged along the circumference of the available space. Figure 7-8 shown.

[0047] According to the embodiments of the present invention, the present invention mainly reduces the height of the junction box by reducing the size and height of the opening in the middle of the junction box and changing the shape of the opening, and is suitable for places with high requirements on the height of the motor.

[0048] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

Claims

1. An explosion-proof motor junction box structure, characterized in that: The junction box is in an irregular trapezoidal box shape, comprising a first junction box cover (1), a junction box body (2), a junction board (3) and a second junction box cover (4); the enclosed area surrounded by the first junction box cover (1), the junction box body (2) and the second junction box cover (4) is a cavity; a junction board (3) is arranged inside the junction box; low-voltage terminals (5) and main terminals (6) are mounted on the junction board (3); the first junction box cover (1) and the second junction box cover (4) are respectively fixed to the upper part and the side part of the junction box; an arc-shaped mounting hole (7) is provided on the junction box body (2) corresponding to the second junction box cover (4) being fixed.

2. The explosion-proof motor junction box structure according to claim 1, characterized in that: The first junction box cover (1) is planar.

3. The explosion-proof motor junction box structure according to claim 1, characterized in that: The second junction box cover (4) is flat.

4. The explosion-proof motor junction box structure according to claim 1, characterized in that: The bottom of the junction box body (2) is a curved surface, and the left and right side surfaces are symmetrically inclined surfaces. The upper ends of the two side surfaces are vertical planes, and the lower ends are inclined surfaces that tilt outward from top to bottom.

5. The explosion-proof motor junction box structure according to claim 4, characterized in that: The vertical planes and the inclined planes on the two side surfaces of the junction box body (2) are integrally connected.

6. The explosion-proof motor junction box structure according to claim 1, characterized in that: The distance between any position on the mounting hole (7) and the edge of the junction box should not be less than the minimum joint surface length.

7. The explosion-proof motor junction box structure according to claim 1, characterized in that: The first junction box cover (1), the second junction box cover (4) and the junction box body (2) are fixedly connected by bolts.

8. A method for arranging terminals and terminals in an explosion-proof motor junction box, based on the explosion-proof motor junction box structure according to any one of claims 1 to 7, characterized in that: The steps include: First, determine the position of the low-voltage terminal. Draw a circle with the center of the low-voltage terminal as the center and the minimum distance of the electrical clearance required by the low-voltage terminal as the radius. Make the edge of the circle tangent to the edge of the junction box to determine the center of the low-voltage terminal, that is, the position of the low-voltage terminal. Next, determine the position of the outermost main terminal. Draw a circle with the center of the main terminal as the center and the minimum distance of the electrical clearance required by the main terminal as the radius. Make the edge of the circle tangent to the edge of the junction box. Determine the center of the outermost main terminal, that is, the position of the outermost main terminal. Finally, determine the positions of other main terminals, ensure that the circles drawn with the required minimum electrical clearance distance as the radius of adjacent main terminals are tangent to each other, and obtain the positions of other main terminals.

9. A method for opening a hole in an explosion-proof motor junction box, based on the explosion-proof motor junction box structure according to any one of claims 1 to 7, characterized in that: The steps include: When opening the mounting hole on the motor junction box, you need to first draw the opening circle corresponding to the position of the low-voltage terminal on the wire box, and then draw the opening circle corresponding to the position of the main terminal in turn. All the opening circles are used as inscribed circles, and the figure formed by connecting the tangents of the upper and lower vertices of the opening circle in the vertical direction is used as the shape of the mounting hole.

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