Motor junction box structure and explosion-proof motor

Abstract

The utility model discloses a motor junction box structure and an explosion-proof motor, and the structure comprises a box body which is internally provided with a wiring cavity, and the box body is provided with an air hole which is communicated with the wiring cavity and the outside; the ventilation valve is arranged on the ventilation hole from the outer end of the ventilation hole; the plug is arranged in the air hole from the inner end of the air hole; wherein an anti-explosion gap is formed between the plug and the box body, and the ventilation valve is suitable for being communicated with the wiring cavity through the anti-explosion gap. According to the utility model, the plug is arranged, and the explosion-proof gap between the plug and the box body can play a role of explosion-proof joint surfaces, so that the ventilation valve can be a common ventilation valve, and the sizes of the ventilation valve and the junction box are effectively reduced.

Description

Technical Field

[0001] The utility model relates to a motor, in particular to a motor junction box structure and an explosion-proof motor. Background Art

[0002] The motor junction box primarily connects the motor's internal lead wires to the external power lines. During motor operation, a pressure differential between the inside and outside of the junction box can affect the box's seal and, in severe cases, even cause the box to explode. Therefore, existing junction boxes are typically equipped with a vent valve to balance the internal and external pressures.

[0003] When motors are used in coal mining, oil and gas, petrochemical, and other operating environments, high explosion-proof requirements are imposed on the motors. Therefore, in these environments, special explosion-proof vent valves are often used to ensure a reliable explosion-proof interface between the vent valve and the junction box. However, the overall size of explosion-proof vent valves increases the overall size of the junction box, hindering the trend towards motor miniaturization.

[0004] Therefore, it is necessary to improve the prior art to overcome the above defects. Utility Model Content

[0005] The purpose of the utility model is to provide a motor junction box structure and an explosion-proof motor, which ensure explosion-proof performance while avoiding increasing the volume of the air vent valve.

[0006] The purpose of the utility model is achieved through the following technical solutions: a motor junction box structure, comprising:

[0007] The box body has a wiring cavity formed therein and a vent hole communicating with the wiring cavity and the outside;

[0008] a vent valve, mounted on the vent hole from the outer end of the vent hole;

[0009] A plug is installed in the vent hole from the inner end of the vent hole;

[0010] Wherein, an explosion-proof gap is formed between the plug and the box body, and the air valve is suitable for being connected to the wiring cavity through the explosion-proof gap.

[0011] Furthermore, the plug includes:

[0012] A plug body is inserted into the vent hole, and a first explosion-proof gap is formed between the plug body and the vent hole;

[0013] a cover portion connected to one end of the plug body and covering the inner end of the vent hole, wherein a second explosion-proof gap is formed between the cover portion and the inner wall of the wiring cavity;

[0014] Wherein, the motor junction box structure includes a fastener, and the fastener is suitable for fixing the cover in the wiring cavity.

[0015] Furthermore, the outer contours of the plug body and the cover are both circular and coaxial, the plug body is coaxially inserted into the air vent and is gap-matched with the air vent, and the outer diameter of the cover is larger than the outer diameter of the plug body.

[0016] Furthermore, the vent hole comprises:

[0017] a first hole portion, one end of which is the outer end of the vent hole, and the vent valve is installed in the first hole portion;

[0018] a second hole portion, one end of which is connected to the other end of the first hole portion, the other end of which is the inner end of the vent hole, and the plug body is inserted into the second hole portion;

[0019] The inner diameter of the first hole portion is smaller than the inner diameter of the second hole portion, a step surface is formed between the first hole portion and the second hole portion, and a gap greater than zero is formed between the plug body and the step surface.

[0020] Furthermore, the fastener is a threaded member connected between the cover and the inner wall of the wiring cavity. There are multiple fasteners, and they are evenly distributed along the circumference of the cover.

[0021] Furthermore, the fastener outer shell is provided with a gasket, the gasket corresponds to the fastener one-to-one, and the gasket is held between the cover and the inner wall of the wiring cavity.

[0022] Furthermore, a convex portion is provided on the outer wall of the box body, and the air vent runs through from the protruding end of the convex portion to the wiring cavity.

[0023] Furthermore, the motor junction box structure includes:

[0024] a partition, disposed in the box body and adapted to separate the wiring cavity into a first cavity portion and a second cavity portion that are independent of each other;

[0025] at least one first terminal, passing through the partition, with two ends respectively located in the first cavity and the second cavity;

[0026] at least one second terminal, disposed on the box body, with one end thereof extending into the second cavity and the other end located outside;

[0027] The air vent is connected to the first cavity, and the box body is provided with a wiring opening connected to the first cavity and the outside.

[0028] Furthermore, the air-permeable valve and the wiring port are arranged on opposite sides of the box body.

[0029] In addition, the utility model also provides an explosion-proof motor, including the aforementioned motor junction box structure.

[0030] Compared with the prior art, the present invention has the following beneficial effects: the present invention provides a vent valve 200, which is connected to the junction box and the inside of the motor. When the air pressure inside the motor and / or the wiring cavity 110 is too high, the pressure is transmitted to the vent valve 200 through the explosion-proof gap, so that the vent valve 200 can balance the air pressure inside the junction box and the motor in time, preventing the air pressure inside the motor from being too high, affecting the airtightness of the entire machine, avoiding condensation inside the motor, protecting the motor and the junction box, and at the same time, when an explosion occurs inside the motor, harmful gases can be discharged in time; in addition, by providing a plug, the explosion-proof gap between the plug and the box body can play the role of an explosion-proof joint surface. When an explosion occurs inside the motor, only a small amount of flame enters the explosion-proof gap, thereby effectively blocking the flame, and then effectively preventing the flame from being transmitted from the outer end of the vent hole to the outside of the junction box, playing an explosion-proof role. Therefore, the vent valve can adopt an ordinary type of vent valve instead of an explosion-proof vent valve, effectively reducing the size of the vent valve and the junction box, which is conducive to the development trend of miniaturization of motors. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a cross-sectional schematic diagram of the motor junction box structure of the present utility model.

[0032] Figure 2 yes Figure 1 A partial enlarged view of point A.

[0033] Figure 3 It is a structural diagram of the motor junction box structure of the utility model.

[0034] Description of reference numerals:

[0035] 100. Box body; 110. Wiring cavity; 120. Wiring port; 130. Air vent; 131. First hole portion; 132. Second hole portion; 133. Step surface; 140. Protrusion; 150. First cavity portion; 160. Second cavity portion; 170. Connecting plate; 200. Air valve; 210. Sealing ring; 300. Plug; 310. Plug body; 320. Cover; 400. Fastener; 410. Gasket; 500. Partition; 600. First terminal; 700. Second terminal. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. It will be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some, rather than all, structures related to the present application are shown in the accompanying drawings. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0037] As used herein, the terms "comprise," "comprising," and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, method, product, or apparatus.

[0038] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0039] See also Figures 1 to 3 The figure shows a motor junction box structure according to a preferred embodiment of the present invention, which is used to be installed on a motor to connect to the cables inside the motor (not shown). The explosion-proof junction box includes a box body 100, which has a wiring cavity 110 formed therein and a wiring opening 120 connecting the wiring cavity 110 with the outside. The motor housing is connected to the wiring opening 120, so that the cables inside the motor can be introduced into the box body 100 through the wiring opening 120.

[0040] Furthermore, the box body 100 is provided with an air vent 130 connecting the wiring cavity 110 with the outside. The motor junction box structure includes a vent valve 200 installed in the vent 130. The vent valve 200 is installed in the vent 130 from the outer end of the vent 130. However, to ensure the explosion-proof performance of the junction box, the vent valve 200 needs to be an explosion-proof vent valve. Preferably, the motor junction box structure also includes a plug 300. The plug 300 is installed in the vent 130 from the inner end of the vent 130. An explosion-proof gap is formed between the plug 300 and the box body 100. The vent valve 200 is connected to the wiring cavity 110 through the explosion-proof gap. The outer end of the vent 130 specifically refers to the end of the vent 130 that connects to the outside, while the inner end refers to the end of the vent 130 that connects to the wiring cavity 110.

[0041] The present invention provides a breather valve 200, which is in communication with the junction box and the interior of the motor. When the air pressure inside the motor and / or the wiring cavity 110 is too high, the pressure is transmitted to the breather valve 200 through the explosion-proof gap, so that the breather valve 200 can balance the air pressure inside the junction box and the motor in time, preventing the air pressure inside the motor from being too high, affecting the airtightness of the entire machine, avoiding condensation inside the motor, protecting the motor and the junction box, and at the same time, when an explosion occurs inside the motor, harmful gases can be discharged in time; in addition, by providing the plug 300, the explosion-proof gap between the plug 300 and the box body 100 can play the role of an explosion-proof joint surface. When an explosion occurs inside the motor, only a small amount of flame can enter the explosion-proof gap, thereby effectively blocking the flame, and further effectively preventing the flame from being transmitted from the outer end of the air vent 130 to the outside of the junction box, playing an explosion-proof role. Therefore, the breather valve 200 can adopt a common type of breather valve instead of an explosion-proof breather valve, effectively reducing the size of the breather valve 200 and the junction box, which is conducive to the development trend of miniaturization of motors.

[0042] Furthermore, a protrusion 140 is formed on the outer wall of the box body 100, and the air valve 200 extends from the protruding end of the protrusion 140 to the wiring cavity 110. This structure effectively increases the depth of the air hole 130, ensuring that the air hole 130 can simultaneously accommodate the air valve 200 and the plug 300. This prevents interference between the air valve 200 and the plug 300 while also avoiding an increase in the overall wall thickness of the box body 100, saving material and reducing the volume of the junction box. Furthermore, the increased depth of the air hole 130 increases the path required for flames within the wiring cavity 110 to flow to the outer end of the air hole 130, further improving explosion-proof performance.

[0043] Furthermore, in this embodiment, the air valve 200 is a conventional air valve 200 , which is threadedly connected to the air hole 130 , and a sealing ring 210 is abutted between the air valve 200 and the outer end of the air hole 130 to improve the sealing performance of the outer end of the air hole 130 .

[0044] The plug 300 includes a plug body 310 and a cover 320. The plug body 310 is inserted into the vent 130. The cover 320 is connected to one end of the plug body 310 and covers the inner end of the vent 130. The explosion-proof gap includes a first explosion-proof gap formed between the plug body 310 and the vent 130, and a second explosion-proof gap formed between the cover 320 and the inner wall of the wiring cavity 110.

[0045] By adopting the plug 300 of the above structure, the explosion-proof joint surface formed between the plug 300 and the box body 100 is a stopper-type structure, which has better explosion-proof performance; and the improvement of explosion-proof performance can be achieved by increasing the radial size of the cover 320 in the air vent 130, that is, increasing the range of the second explosion-proof gap, increasing the path required for the flame to flow to the outer end of the air vent 130, and there is no need to increase the hole depth of the air vent 130, thereby avoiding increasing the external size of the junction box; in addition, since the radial size of the wiring cavity 110 in the air vent 130 is usually larger, the size of the cover 320 is not easily restricted by the wiring cavity 110 and is easy to adjust.

[0046] Furthermore, in this embodiment, the outer contours of the plug body 310 and the cover 320 are both circular and coaxial, facilitating installation of the plug 300. The plug body 310 is coaxially inserted into the vent 130 and has a clearance fit therebetween. This clearance is preferably greater than zero to ensure that the vent valve 200 can promptly obtain information about the air pressure within the wiring cavity 110. The outer diameter of the cover 320 is larger than that of the plug body 310, ensuring a reliable second explosion-proof gap is formed between it and the inner end of the vent 130.

[0047] The vent 130 includes a first hole portion 131 and a second hole portion 132. One end of the first hole portion 131 serves as the outer end of the vent 130, while one end of the second hole portion 132 connects to the other end of the first hole portion 131 and serves as the inner end of the vent 130. The vent valve 200 is installed in the first hole portion 131, and the plug body 310 is inserted into the second hole portion 132. Preferably, the inner diameter of the first hole portion 131 is smaller than the inner diameter of the second hole portion 132. A stepped surface 133 is formed between the first hole portion 131 and the second hole portion 132. The axial projection of the plug body 310 completely covers the first hole portion 131. A gap greater than zero exists between the plug body 310 and the stepped surface 133 to prevent airflow from the second hole portion 132 from flowing into the first hole portion 131. By adopting the above structure, when a flame flows along the first explosion-proof gap toward the vent valve 200 , the step surface 133 can block the flame, preventing the flame from directly impacting the vent valve 200 , thereby reducing the probability of damage to the vent valve 200 .

[0048] Furthermore, the motor terminal box structure includes a fastener 400, which is suitable for fixing the cover 320 to the inner wall of the wiring cavity 110. In this embodiment, the fastener 400 is specifically a threaded member connected between the cover 320 and the inner end of the vent 130, and the threaded member includes a screw, bolt, etc. Of course, in other embodiments, a snap-fit ​​structure, adhesive bonding, etc. can also be used to achieve fixation. Preferably, there are multiple fasteners 400, and they are evenly distributed along the circumference of the cover 320 to improve the tightness of the connection between the plug 300 and the box body 100.

[0049] Specifically, the cover portion 320 is provided with a first connecting hole (not shown) along the axial direction of the air vent 130. The first connecting hole corresponds one-to-one to the fastener 400. The first connecting hole can be a threaded hole or a light hole adapted to the fastener 400. The inner wall of the wiring cavity 110 corresponding to the inner end of the air vent 130 is recessed inward to form a second connecting hole (not shown). The second connecting hole corresponds one-to-one to the first connecting hole and is coaxial with the first connecting hole. The second connecting hole is a threaded hole adapted to the fastener 400. The fastener 400 is suitable for being installed into the first connecting hole through the end of the first connecting hole facing away from the second connecting hole, and being threadedly connected to the second connecting hole.

[0050] In one embodiment, after the fastener 400 is screwed into the first connecting hole and the second connecting hole, it is in a loose state, that is, the distance between the cap of the fastener 400 and the inner wall of the wiring cavity 110 is greater than the thickness of the cover 320, so that there is a gap greater than zero between the cover 320 and the inner wall of the wiring cavity 110 to ensure the formation of a second explosion-proof gap. However, with the above structure, the reliability of the plug 300 after being fixed is relatively poor. As a preferred embodiment, the fastener 400 is provided with a gasket 410, and the gasket 410 corresponds to the fastener 400 one-to-one. After the fastener 400 is screwed into the first connecting hole and the second connecting hole, it can be selected to a tight state so that the gasket 410 is held between the cover 320 and the inner wall of the wiring cavity 110, and the second explosion-proof gap can be formed. At the same time, the plug 300 is tightly connected to the inner wall of the wiring cavity 110 to prevent the plug 300 from loosening after long-term use. The gasket 410 may be specifically an O-ring made of an elastic material, such as rubber, silicone, etc.

[0051] Furthermore, the motor terminal box structure also includes a partition 500, a first terminal 600, and a second terminal 700. The partition 500 is disposed within the box body 100 and is adapted to separate the wiring cavity 110 into a first cavity 150 and a second cavity 160, which are mutually independent. The partition 500 can be integrally formed with the box body 100 or separately formed and then assembled together. In this embodiment, integral molding is preferred to simplify the assembly process.

[0052] There is at least one first terminal 600, which is fixedly inserted into the partition 500. The two ends of the first terminal 600 are respectively located in the first cavity 150 and the second cavity 160. In this embodiment, there are multiple first terminal 600, which are arranged side by side. The partition 500 has a mounting hole extending perpendicular to its surface. The mounting hole corresponds to the first terminal 600 one-to-one. The first terminal 600 can be threaded into the mounting hole to improve the convenience of installation. There is at least one second terminal 700, which corresponds to the first terminal 600 one-to-one. The second terminal 700 is set on the box body 100, with one end extending into the second cavity 160 and the other end located outside. The box body 100 can have an opening corresponding to the second terminal 700. The second terminal 700 is fixedly inserted into the opening and is threaded or welded to the opening. The air vent 130 is connected to the first cavity 150, and the wiring port 120 connects the first cavity 150 and the outside to ensure that the air valve 200 can obtain the air pressure status inside the motor in a timely manner. The cable inside the motor can be connected to one end of the first terminal 600 located in the first cavity 150, and a cable is also connected between the other end of the first terminal 600 and one end of the second terminal 700, thereby connecting the cable inside the motor to the second terminal 700, and the other end of the second terminal 700 can be connected to the external power line. By adopting the above structure, the partition 500 can separate the wiring cavity 110 into the first cavity 150 that interfaces with the inside of the motor and the second cavity 160 that interfaces with the external power supply. When an explosion occurs inside or outside the motor, the partition 500 can effectively block the impact and / or flames generated by the explosion, ensuring that the interior of the junction box has reliable explosion-proof performance.

[0053] Preferably, the wiring opening 120 is opened parallel to the surface of the partition 500 to reduce the impact on the partition 500 in the event of an explosion inside the motor. The vent valve 200 and wiring opening 120 are arranged on opposite sides of the box body 100 to ensure that the vent valve 200 can respond promptly if the pressure inside the motor is unbalanced.

[0054] Furthermore, both sides of the vertical partition 500 of the box body 100 are open. The junction box structure includes connecting plates 170 corresponding to each open side, and the connecting plates 170 are removably attached to the open sides. With this structure, during the junction box assembly process, the operator only needs to remove the connecting plates 170 from the box body 100. The operator can then easily install the plug 300, the first terminal 600, and the cables through the open sides.

[0055] In addition, the utility model also provides an explosion-proof motor, including a casing (not shown), a motor body (not shown) and the aforementioned motor junction box structure. The casing is provided with an opening, the motor junction box structure is installed on the casing, and the wiring opening 120 is connected to the opening of the casing. The motor body is installed in the casing, and its cable extends into the motor junction box structure through the opening and the wiring opening 120 to connect with one end of the first terminal 600. A cable is connected between the other end of the first terminal 600 and one end of the second terminal 700, and the other end of the second terminal 700 is connected to an external power line.

[0056] The above description is only an implementation method of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of this application, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A motor junction box structure, characterized in that: include: The box body (100) has a wiring cavity (110) formed therein, and a vent hole (130) communicating between the wiring cavity (110) and the outside is provided on the box body (100); A vent valve (200) is installed on the vent hole (130) from the outer end of the vent hole (130); A plug (300) is installed on the vent hole (130) from the inner end of the vent hole (130); An explosion-proof gap is formed between the plug (300) and the box body (100), and the air-permeable valve (200) is adapted to be connected to the wiring cavity (110) through the explosion-proof gap.

2. The motor junction box structure according to claim 1, characterized in that: The plug (300) comprises: A plug body (310) is inserted into the vent hole (130), and a first explosion-proof gap is formed between the plug body (310) and the vent hole (130); A cover portion (320) is connected to one end of the plug body (310) and covers the inner end of the vent hole (130), and a second explosion-proof gap is formed between the cover portion (320) and the inner wall of the wiring cavity (110); The motor junction box structure includes a fastener (400), and the fastener (400) is suitable for fixing the cover (320) in the wiring cavity (110).

3. The motor junction box structure according to claim 2, characterized in that: The outer contours of the plug body (310) and the cover (320) are both circular and coaxial. The plug body (310) is coaxially inserted into the air vent (130) and is loosely fitted with the air vent (130). The outer diameter of the cover (320) is greater than the outer diameter of the plug body (310).

4. The motor junction box structure according to claim 3, characterized in that: The vent hole (130) includes: a first hole portion (131), one end of which is the outer end of the vent hole (130), and the vent valve (200) is installed in the first hole portion (131); A second hole portion (132), one end of which is connected to the other end of the first hole portion (131), and the other end of which is the inner end of the vent hole (130), and the plug body (310) is inserted into the second hole portion (132); The inner diameter of the first hole portion (131) is smaller than the inner diameter of the second hole portion (132), a step surface (133) is formed between the first hole portion (131) and the second hole portion (132), and a gap greater than zero is present between the plug body (310) and the step surface (133).

5. The motor junction box structure according to claim 2, characterized in that: The fastener (400) is a threaded member connected between the cover (320) and the inner wall of the wiring cavity (110). There are multiple fasteners (400) and they are evenly distributed along the circumference of the cover (320).

6. The motor junction box structure according to claim 5, characterized in that: The outer cover of the fastener (400) is provided with a gasket (410), the gasket (410) corresponds to the fastener (400) one by one, and the gasket (410) is held between the cover (320) and the inner wall of the wiring cavity (110).

7. The motor junction box structure according to claim 1, characterized in that: The outer wall of the box body (100) is provided with a convex portion (140), and the air vent (130) passes through the protruding end of the convex portion (140) to the wiring cavity (110).

8. The motor junction box structure according to any one of claims 1 to 7, characterized in that: The motor junction box structure includes: A partition (500) is disposed in the box body (100) and is suitable for separating the wiring cavity (110) into a first cavity portion (150) and a second cavity portion (160) that are independent of each other; At least one first terminal (600) is inserted into the partition (500), with two ends respectively located in the first cavity (150) and the second cavity (160); at least one second terminal (700), disposed on the box body (100), with one end extending into the second cavity (160) and the other end located outside; The vent hole (130) is in communication with the first cavity (150), and the box body (100) is provided with a wiring opening (120) in communication with the first cavity (150) and the outside.

9. The motor junction box structure according to claim 8, characterized in that: The vent valve (200) and the wiring port (120) are arranged oppositely on two sides of the box body (100).

10. An explosion-proof motor, characterized in that: The motor junction box structure comprises the motor junction box structure according to any one of claims 1 to 9.

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