Mining low-voltage leakage protection device

Abstract

The utility model provides a mining low-voltage leakage protection device, which comprises a voltage transformer and a fusible core, the voltage transformer comprises an upper shell and a lower shell, a fusible core mounting structure is arranged in the upper shell, an iron core is arranged in the lower shell, a secondary side coil is wound on the iron core, an insulating layer is wrapped on the secondary side coil, and the fusible core mounting structure is arranged in the lower shell. A primary side coil is wound on the insulating layer, the primary side coil is connected with one end of the fusible core through a wire, and the other end of the fusible core is connected with a primary side connector; the fusible core is sealed in the voltage transformer, so that dust in a mine is prevented from being adsorbed on the fusible core in daily maintenance, and the service life of the fusible core is prolonged; in the application, the voltage transformer is connected below the feed switch, when a fuse core is fused due to short circuit, the primary side is disconnected, and the relay connected to the secondary side realizes the disconnection of the circuit breaker switch, so that the arrangement of an isolating switch is reduced, and the size of the leakage protection device is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of mine leakage protection, and more specifically, particularly relates to a low-voltage leakage protection device for mines. Background Art

[0002] Most of the mine power grids are powered by cables. Due to the harsh power supply environment, single-phase leakage or single-phase grounding faults often occur in cable lines, which not only cause personal electric shock, but also may cause gas and coal dust explosions, or even premature detonation of electrical detonators. According to Article 434 of the Coal Mine Safety Regulations: Leakage detection protection devices with leakage lockout or selective leakage detection protection devices should be installed on underground low-voltage feeder lines. If there is no such device, a leakage detection device that automatically cuts off the leakage feeder line must be installed.

[0003] The neutral points of the low-voltage power grid in my country's coal mines are all ungrounded, and are basically divided into three levels: the main feeder switch Q1, the branch feeder switch Q2, and the magnetic starter Q3. Usually, the selective leakage protection device is set at the main feeder switch and the branch feeder switch, and the magnetic starter is generally only equipped with a leakage lock, that is, a two-level selective leakage protection system is adopted. In order to ensure selectivity, the upper and lower leakage protection devices are delayed to achieve the selectivity of the action. The horizontal selectivity is mostly achieved by the zero-sequence power direction protection principle, but the leakage protection device at the main automatic feeder switch adopts the protection principle of additional DC.

[0004] After confirming the leakage, the main feeder switch Q1 and the branch feeder switch Q2 are disconnected by opening and closing the relay protection device; the relay protection device is connected to the secondary side of the voltage transformer to supply electric energy to the relay protection device.

[0005] In the power regulations, the primary side of the voltage transformer needs to be connected to a fuse and an isolating switch to protect against insulation damage of the voltage transformer, so as to prevent the high voltage on the primary side from entering the secondary equipment side and endangering the safety of the equipment and personnel on the secondary side.

[0006] The prior art CN221101856U discloses a highly sealed voltage transformer, and an integrated structure of a voltage transformer and epoxy resin packaging is well known in the industry.

[0007] The leakage protection device composed of the above-mentioned components installed in the electrical housing is large in size, and the feeder switch and the isolating switch are set repeatedly; the dust in the mine is large, and it is easy to enter the electrical housing during daily maintenance and be adsorbed on the fuse, thereby affecting the use of the fuse.

[0008] Therefore, in view of this, the existing structure and deficiencies are studied and improved, and a low-voltage leakage protection device for mining is provided, in order to achieve a more practical purpose. Utility Model Content

[0009] In order to solve the above technical problems, the utility model provides a low-voltage leakage protection device for mining, so as to solve the problems that the leakage protection device is large in size, the feeder switch and the isolating switch are repeatedly set, and the fuse is easy to absorb dust.

[0010] The purpose and effect of the low-voltage leakage protection device for mining of the utility model are achieved by the following specific technical means:

[0011] A low-voltage leakage protection device for mining includes a voltage transformer and a fusible core. The voltage transformer includes an upper shell and a lower shell. A fusible core mounting structure is arranged in the upper shell. An iron core is arranged in the lower shell. A secondary coil is wound on the iron core. An insulating layer is wrapped on the secondary coil. A primary coil is wound on the insulating layer. The primary coil is connected to one end of the fusible core through a wire, and the other end of the fusible core is connected to a primary side connector.

[0012] Preferably, the fusible core installation structure comprises a first column cylinder and a second column cylinder, one end of the second column cylinder is connected to a connecting cylinder, and a plug is threadedly connected inside the connecting cylinder.

[0013] Preferably, the upper shell is a cavity with an opening at the lower end, the first column is welded to the copper wire, and fixed to one end in the upper shell by epoxy resin, and the copper wire is inserted into the primary side joint.

[0014] Preferably, a through hole is provided at the other end of the upper shell, a first internal threaded hole is provided on the outer end surface of the upper shell located around the through hole, and an insulating sealing member for sealing the through hole is also included.

[0015] Preferably, the insulating sealing member includes a sealing column, an end cap, and a fixing hole arranged in the end cap.

[0016] Preferably, a plurality of second internal threaded holes are provided on one end of the cavity of the upper shell body symmetrical to the through hole, the second internal threaded holes are used to connect the connecting tube, and a flange with holes corresponding to the second internal threaded holes is provided at the end of the connecting tube.

[0017] Preferably, the lower shell is a square frame with openings at both ends, the opening of the cavity of the upper shell is connected with a transition part, the transition part is connected with a connecting part, and the connecting part and the lower shell are both provided with connecting holes for connecting the connecting part and the lower shell.

[0018] Preferably, the lower shell is provided with a mounting base plate, the four corners of the mounting base plate are provided with mounting holes, the middle of the mounting base plate is provided with an iron core mounting hole, and the iron core is fixed to the mounting base plate by a clamp.

[0019] Preferably, a capped connecting column is also provided on the mounting base plate.

[0020] Preferably, a secondary side connector is provided on the lower shell, and the secondary side connector is connected to the secondary side coil through a wire.

[0021] Compared with the prior art, the utility model has the following beneficial effects: the fuse core is sealed in the voltage transformer, so that dust in the mine is prevented from being adsorbed on the fuse core during daily maintenance, thereby increasing the service life of the fuse core; in application, the voltage transformer is connected under the feeder switch, and when a short circuit occurs and the fuse core is blown, the primary side is short-circuited, and the relay connected to the secondary side realizes the disconnection of the circuit breaker, thereby reducing the setting of the isolating switch and then reducing the volume of the leakage protection equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a three-dimensional exploded schematic diagram of the utility model;

[0023] Figure 2 It is an exploded schematic diagram of the fuse installation structure of the utility model;

[0024] In the figure: voltage transformer 1, fuse core 2, fuse core mounting structure 3, iron core 4;

[0025] An upper shell 11 and a lower shell 12;

[0026] Transition portion 101, connection portion 102, connection hole 103;

[0027] A primary side connector 110, a through hole 111, a first internal threaded hole 112, an insulating plugging member 113, and a second internal threaded hole 114;

[0028] Installation base plate 121, installation hole 122, core installation hole 123, capped connection column 124, secondary side connector 125;

[0029] Copper wire 1101;

[0030] Blocking column 1131, end cap 1132, fixing hole 1133;

[0031] A first column 31, a second column 32, a connecting tube 33, a plug 34, and a flange 35 with holes;

[0032] The secondary side coil 41 , the insulating layer 42 , the primary side coil 43 , and the clamp 44 . DETAILED DESCRIPTION

[0033] The following is a further detailed description of the implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0034] In the description of the present invention, unless otherwise specified, "multiple" means two or more; the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third" and the like are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" 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. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] Example:

[0037] The utility model provides a low-voltage leakage protection device for mining, as shown in the attached Figure 1-2 As shown, a low-voltage leakage protection device for mining includes a voltage transformer 1 and a fusible core 2. The voltage transformer 1 includes an upper shell 11 and a lower shell 12. A fusible core mounting structure 3 is arranged in the upper shell 11, and an iron core 4 is arranged in the lower shell 12. A secondary side coil 41 is wound on the iron core 4, an insulating layer 42 is wrapped on the secondary side coil 41, a primary side coil 43 is wound on the insulating layer 42, and the primary side coil 43 is connected to one end of the fusible core 2 through a wire, and the other end of the fusible core 2 is connected to a primary side connector 110.

[0038] The fuse installation structure 3 includes a first column barrel 31 and a second column barrel 32, one end of the second column barrel 32 is connected to a connecting barrel 33, and a plug 34 is connected to the connecting barrel 33 through a thread. The fuse installation structure 3 and the plug 34 are both made of metal. The diameter of the first column barrel 31 is larger than that of the fuse 2, so that one end of the fuse 2 can be inserted into the first column barrel 31; the diameter of the second column barrel 32 is adapted to the diameter of the fuse 2, and is used to connect the other end of the fuse 2, and the other end of the wire connected to the primary side coil 43 is connected to the second column barrel 32 or the connecting barrel 33; the connecting barrel 33 is connected to one end of the second column barrel 32, and the plug 34 is connected to the connecting barrel 33 through a thread. The plug 34 is used to abut against the end of the fuse 2, fix the fuse 2, and prevent the electrical connection from being dummy.

[0039] The upper shell 11 is a cavity with an opening at the lower end, the first column 31 is welded to the copper wire 1101 and fixed at one end in the upper shell 11 by epoxy resin, and the copper wire 1101 is inserted into the primary side connector 110. The gap between the copper wire 1101 and the primary side connector 110 is filled with epoxy resin.

[0040] A through hole 111 is disposed at the other end of the upper shell 11 , a first internal threaded hole 112 is disposed on the outer end surface of the upper shell 11 around the through hole 111 , and an insulating plugging member 113 for plugging the through hole 111 is also included.

[0041] The insulating sealing member 113 includes a sealing column 1131 , an end cap 1132 , and a fixing hole 1133 disposed on the end cap 1132 .

[0042] During installation, a bolt is used to be screwed into the first internal threaded hole 112 through the fixing hole 1133 , and the blocking column 1131 blocks the through hole 111 .

[0043] A plurality of second internal threaded holes 114 are provided on one end of the cavity of the upper shell 11 symmetrical to the through hole 111 . The second internal threaded holes 114 are used to connect the connecting tube 33 . The end of the connecting tube 33 is provided with a flange 35 with holes corresponding to the second internal threaded holes 114 .

[0044] The bolt is screwed into the second internal threaded hole 114 through the flange 35 with holes on the connecting tube 33 to fix it.

[0045] It should be noted that the end portion of the upper shell 11 is made of insulating material, that is, the first internal threaded hole 112 and the second internal threaded hole 114 are both formed on the insulating material.

[0046] The lower shell 12 is a square frame with openings at both ends. The opening of the cavity of the upper shell 11 is connected to a transition portion 101, and the transition portion 101 is connected to a connecting portion 102. Both the connecting portion 102 and the lower shell 12 are provided with connecting holes 103 for connecting the connecting portion 102 and the lower shell 12.

[0047] The lower shell 12 is provided with a mounting base plate 121 . The mounting base plate 121 has mounting holes 122 at four corners. The middle of the mounting base plate 121 is provided with an iron core mounting hole 123 . The iron core 4 is fixed to the mounting base plate 121 by a clamp 44 .

[0048] The installation base plate 121 is also provided with a capped connecting column 124 .

[0049] The lower housing 12 is provided with a secondary side connector 125 , and the secondary side connector 125 is connected to the secondary side coil 41 through a wire.

[0050] Specifically, the iron core 4 wound with the secondary coil 41 , the insulating layer 42 , and the primary coil 43 is screwed into the iron core mounting hole 123 through the clamp 44 using bolts, so that the iron core 4 is fixed on the mounting base plate 121 .

[0051] The lower shell 12 is placed on the mounting base 121, and the secondary side connector 125 is connected to the secondary side coil 41 through a wire, leaving a wire connected to the primary side coil 43, and then epoxy resin is injected into the lower shell 12. After the resin is cured, the mutual inductance coil is sealed.

[0052] At the same time, the solidified resin connects the capped connecting column 124 to achieve the connection between the mounting base plate 121 and the lower shell 12 .

[0053] The fusible core 2 is passed through the through hole 111, the connecting tube 33, the second column tube 32 in sequence, and inserted into the first column tube 31, and then the plug 34 is screwed into the connecting tube 33 to achieve the fixed connection of the fusible core 2, and finally the through hole 111 is blocked with the insulating plugging piece 113 to achieve insulation.

[0054] Afterwards, the upper shell 11 and the lower shell 12 are connected by bolting the connecting portion 102 and the connecting hole 103 of the lower shell 12; before the connection, the wire reserved for connecting the primary side coil 43 needs to be connected to the second column tube 32 or the connecting tube 33.

[0055] Compared with the prior art, the utility model has the following beneficial effects: the fuse core is sealed in the voltage transformer, so that dust in the mine is prevented from being adsorbed on the fuse core during daily maintenance, thereby increasing the service life of the fuse core; in application, the voltage transformer is connected under the feeder switch, and when a short circuit occurs and the fuse core is blown, the primary side is short-circuited, and the relay connected to the secondary side realizes the disconnection of the circuit breaker, thereby reducing the setting of the isolating switch and then reducing the volume of the leakage protection equipment.

[0056] The embodiments of the present invention are provided for the purpose of illustration and description, and are not intended to be exhaustive or to limit the present invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described to better illustrate the principles and practical applications of the present invention, and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

Claims

1. A low-voltage leakage protection device for mining, comprising a voltage transformer (1) and a fuse (2), characterized in that: The voltage transformer (1) comprises an upper shell (11) and a lower shell (12); a fusible core installation structure (3) is arranged in the upper shell (11); an iron core (4) is arranged in the lower shell (12); a secondary coil (41) is wound on the iron core (4); an insulating layer (42) is wrapped on the secondary coil (41); a primary coil (43) is wound on the insulating layer (42); the primary coil (43) is connected to one end of the fusible core (2) through a wire; and the other end of the fusible core (2) is connected to a primary side connector (110).

2. The low voltage leakage protection device for mining as claimed in claim 1, characterized in that: The fusible core installation structure (3) comprises a first column tube (31) and a second column tube (32); one end of the second column tube (32) is connected to a connecting tube (33); a plug (34) is threadedly connected inside the connecting tube (33).

3. The low voltage leakage protection device for mining as claimed in claim 2, characterized in that: The upper shell (11) is a cavity with an opening at the lower end. The first column (31) is welded to the copper wire (1101) and fixed at one end inside the upper shell (11) by epoxy resin. The copper wire (1101) is inserted into the primary side connector (110).

4. The low voltage leakage protection device for mining as claimed in claim 3, characterized in that: The other end of the upper shell (11) is provided with a through hole (111), the outer end surface of the upper shell (11) located around the through hole (111) is provided with a first internal threaded hole (112), and also includes an insulating sealing member (113) for sealing the through hole (111).

5. The low voltage leakage protection device for mining as claimed in claim 4, characterized in that: The insulating sealing member (113) comprises a sealing column (1131), an end cap (1132), and a fixing hole (1133) arranged on the end cap (1132).

6. The low voltage leakage protection device for mining as claimed in claim 4, characterized in that: A plurality of second internal threaded holes (114) are provided on one end of the cavity of the upper shell (11) symmetrical to the through hole (111), and the second internal threaded holes (114) are used to connect the connecting tube (33), and a flange (35) with holes corresponding to the second internal threaded holes (114) is provided at the end of the connecting tube (33).

7. The low voltage leakage protection device for mining as claimed in claim 1, characterized in that: The lower shell (12) is a square frame with openings at both ends; a transition portion (101) is connected to the opening of the cavity of the upper shell (11); the transition portion (101) is connected to a connecting portion (102); and connecting holes (103) for connecting the connecting portion (102) and the lower shell (12) are provided on the connecting portion (102) and the lower shell (12).

8. The low voltage leakage protection device for mining as claimed in claim 7, characterized in that: The lower shell (12) is provided with a mounting base plate (121), the four corners of the mounting base plate (121) are provided with mounting holes (122), the middle of the mounting base plate (121) is provided with an iron core mounting hole (123), and the iron core (4) is fixed to the mounting base plate (121) by a clamp (44).

9. The low voltage leakage protection device for mining as claimed in claim 8, characterized in that: The installation base plate (121) is also provided with a capped connecting column (124).

10. The low voltage leakage protection device for mining as claimed in claim 7, characterized in that: A secondary side connector (125) is provided on the lower housing (12), and the secondary side connector (125) is connected to the secondary side coil (41) via a wire.

Images