A high-precision current transformer for low-voltage switches

Abstract

The utility model provides a high-precision current transformer for low-voltage switches, comprising a body and an iron core arranged in the body, a wire fixing structure is also arranged on the body, the wire fixing structure comprises a shell, a shrinking ring body, at least three clamping rods and a threaded rotating rod, and the wire fixing structure is coaxially arranged on both sides of the body. By respectively arranging the wire fixing structures on both sides of the body, the clamping rod moves inward to clamp the cable so that it is located on the axis of the iron core, so as to achieve the same distance between the cable passing through the transformer and the iron core inside the transformer, thereby improving the measurement accuracy.

Description

Technical Field

[0001] The utility model belongs to the technical field of mining area electric power metering, and more specifically, particularly relates to a high-precision current transformer for low-voltage switches. Background Art

[0002] As an important metering device in the power system, the accuracy of the current transformer directly affects the metering quality of the power system. For the threading current transformer, we will find in actual applications that when the rated value of the current transformer is not very large, inaccurate measurement often occurs. In addition to the influence of factors such as long service life, the installation position and posture of the current transformer are one of the main factors affecting the measurement accuracy. If the installation position of the current transformer deviates from the center line of the cable, the distance between the iron core inside the transformer and the cable is uneven, which will cause errors.

[0003] In order to improve the measurement accuracy of the current transformer, we need to make the distance between the cable passing through the transformer and the iron core inside the transformer consistent to reduce the occurrence of errors.

[0004] Therefore, in view of this, the existing structure and defects are studied and improved, and a high-precision current transformer for low-voltage switches is provided, in order to achieve a more practical purpose. Utility Model Content

[0005] In order to solve the above technical problems, the utility model provides a high-precision current transformer for low-voltage switches to solve the problem of inaccurate measurement of the current transformer caused by uneven distance between the iron core and the cable inside the transformer.

[0006] The purpose and effect of the high-precision current transformer for low-voltage switch of the utility model are achieved by the following specific technical means:

[0007] A high-precision current transformer for a low-voltage switch comprises a main body and an iron core arranged in the main body. The main body is also provided with a fixed wire structure, which comprises a shell, a shrink ring body, at least three clamping rods and a threaded rotating rod. The fixed wire structure is coaxially arranged on both sides of the main body.

[0008] Furthermore, the shrink ring body is an open structure, and a first connecting block and a second connecting block are fixedly provided at both ends of the shrink ring body, and an internal thread through hole is provided on the second connecting block.

[0009] Furthermore, the first connecting block is fixedly connected to the inner wall of the shell, and a through hole is provided on the first connecting block.

[0010] Furthermore, the cross section of the shrink ring body is U-shaped.

[0011] Furthermore, an arc-shaped clamping head is arranged at one end of the clamping rod, and a limiting ring and a spring sleeved on the clamping rod are fixedly arranged on the clamping rod.

[0012] Furthermore, the arc-shaped clamping head is provided with a threaded column, and the end surface of the clamping rod is adapted to be provided with an internal threaded inner hole.

[0013] Furthermore, the shell is provided with at least three first through holes and one second through hole.

[0014] Furthermore, the clamping rod passes through the first through hole to connect to the arc-shaped clamping head, and the threaded rotating rod is connected to the internal threaded through hole through the second through hole.

[0015] Furthermore, a screw cap is provided at the end of the threaded screw rod.

[0016] Furthermore, a notch is provided on the screw cap.

[0017] Compared with the prior art, the utility model has the following beneficial effects: by arranging fixed wire structures on both sides of the main body, the clamping rod moves inward to clamp the cable so that it is located on the axis of the iron core, so as to achieve a consistent distance between the cable passing through the transformer and the iron core inside the transformer, thereby improving the measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional structural schematic diagram of the utility model.

[0019] Figure 2 It is a schematic diagram of the fixed line structure of the utility model.

[0020] Figure 3 It is a cross-sectional schematic diagram of the wire fixing structure of the utility model.

[0021] In the figure:

[0022] Body 1, iron core 2, fixed wire structure 3;

[0023] Shell 30, shrink ring body 31, clamping rod 32, threaded rotating rod 33;

[0024] A first connecting block 311, a second connecting block 312, an internal thread through hole 313, and a through hole 314;

[0025] Arc-shaped clamping head 321, limiting ring 322, spring 323, internal thread inner hole 324;

[0026] Threaded column 3211;

[0027] A first through hole 301 and a second through hole 302;

[0028] The screw cap 331 and the notch 332 . DETAILED DESCRIPTION

[0029] 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.

[0030] 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.

[0031] 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.

[0032] Example:

[0033] The utility model provides a high-precision current transformer for low-voltage switches. Figure 1-3 As shown, it includes a main body 1 and an iron core 2 arranged in the main body 1. A wire fixing structure 3 is also arranged on the main body 1. The wire fixing structure 3 includes a shell 30, a shrinking ring body 31, at least three clamping rods 32 and a threaded rotating rod 33. The wire fixing structure 3 is coaxially arranged on both sides of the main body 1.

[0034] The main body 1 and the shell 30 are both configured to connect the protruding edge, and the protruding edge openings are connected by bolts, or the main body 1 and the shell 30 are molded as an integral structure to achieve connection between the two. These are all existing technologies and will not be described in detail.

[0035] The shrinking ring body 31 is an open structure, and the shrinking ring body 31 is made of elastic material. The first connecting block 311 and the second connecting block 312 are fixedly provided at both ends of the shrinking ring body 31, and the second connecting block 312 is provided with an internal threaded through hole 313. The first connecting block 311 is fixedly connected to the inner wall of the shell 30, and the first connecting block 311 is provided with a through hole 314.

[0036] A screw cap 331 is disposed at the end of the threaded rotating rod 33 . A notch 332 is disposed on the screw cap 331 . The threaded rotating rod 33 can be rotated by rotating the screw cap 331 or inserting a screwdriver into the notch 332 and rotating it.

[0037] The housing 30 has a second through hole 302 , and the threaded rotary rod 33 is connected to the internal threaded through hole 313 via the second through hole 302 .

[0038] The connecting threaded rotary rod 33 passes through the through hole 314 and is screwed into the internal threaded through hole 313 . The second connecting block 312 is moved axially along the rotating threaded rotary rod 33 by rotating the threaded rotary rod 33 , thereby realizing the expansion or contraction of the shrinking ring body 31 .

[0039] The shrink ring body 31 has a U-shaped cross section, forming a U-shaped groove.

[0040] An arc-shaped clamping head 321 is provided at one end of the clamping rod 32 , and the other end of the clamping rod 32 is located in the U-shaped groove of the shrinking ring body 31 . As the shrinking ring body 31 expands or contracts, the clamping rod 32 slides in the U-shaped groove.

[0041] A limit ring 322 and a spring 323 sleeved on the clamping rod 32 are fixedly provided on the clamping rod 32 .

[0042] When the shrinking ring body 31 shrinks, the end of the clamping rod 32 located in the U-shaped groove abuts against the bottom of the U-shaped groove, and the clamping rod 32 is driven to move along its own axial direction by pressing against the end of the clamping rod 32 .

[0043] In another embodiment, when the shrinking ring body 31 shrinks, the end of the clamping rod 32 located in the U-shaped groove does not abut against the bottom of the U-shaped groove, and the limiting ring 322 arranged on the clamping rod 32 abuts against the side wall of the U-shaped groove. As the shrinking ring body 31 shrinks, the side wall of the U-shaped groove presses against the limiting ring 322, thereby driving the clamping rod 32 to move along its own axial direction.

[0044] The arc-shaped clamping head 321 is provided with a threaded column 3211 , the end surface of the clamping rod 32 is adapted to be provided with an internal threaded inner hole 324 , and the housing 30 is provided with at least three first through holes 301 , through which the clamping rod 32 passes to connect with the arc-shaped clamping head 321 .

[0045] The spring 323 is sleeved on the clamping rod 32, with one end abutting against the limit ring 322 and the other end abutting against the inner wall of the shell 30. The shrinking ring body 31 is driven to shrink by rotating the threaded rotating rod 33, so that the clamping rod 32 extends from the shell 30 through the first through hole 301. At this time, the spring 323 is in a compressed state.

[0046] The arc-shaped clamping head 321 is screwed into the internal threaded inner hole 324 through the threaded column 3211 to connect the arc-shaped clamping head 321 with the clamping rod 32. Then, the threaded rotating rod 33 is rotated to drive the shrinking ring body 31 to expand, and the clamping rod 32 is contracted into the housing 30 under the action of the spring 323, and the arc-shaped clamping head 321 is attached to the outer wall of the housing 30.

[0047] In order to ensure the axial movement of the clamping rod 32 , a sleeve is arranged in the first through hole 301 , the clamping rod 32 passes through the first through hole 301 through the sleeve, and the spring 323 is sleeved on the sleeve.

[0048] The utility model has the following beneficial effects: by respectively arranging the fixed wire structures 3 on both sides of the main body 1, the clamping rod 32 moves axially inward to clamp the cable so that it is located on the axis of the iron core 2, so as to achieve the consistency of the distance between the cable passing through the mutual inductor and the iron core 2 inside the mutual inductor, thereby improving the measurement accuracy.

[0049] 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 high-precision current transformer for a low-voltage switch, comprising a body (1) and an iron core (2) arranged in the body (1), characterized in that: The main body (1) is also provided with a wire fixing structure (3), the wire fixing structure (3) comprising a shell (30), a shrinking ring body (31), at least three clamping rods (32) and a threaded rotating rod (33), and the wire fixing structure (3) is coaxially arranged on both sides of the main body (1).

2. A high-precision current transformer for a low-voltage switch according to claim 1, characterized in that: The shrink ring body (31) is an open structure, and a first connection block (311) and a second connection block (312) are respectively fixedly provided at both ends of the shrink ring body (31), and the second connection block (312) is provided with an internal thread through hole (313).

3. A high-precision current transformer for a low-voltage switch as claimed in claim 2, characterized in that: The first connection block (311) is fixedly connected to the inner wall of the housing (30), and a through hole (314) is provided on the first connection block (311).

4. A high-precision current transformer for a low-voltage switch as claimed in claim 3, characterized in that: The shrink ring body (31) has a U-shaped cross section.

5. A high-precision current transformer for a low-voltage switch as claimed in claim 4, characterized in that: An arc-shaped clamping head (321) is provided at one end of the clamping rod (32), and a limit ring (322) and a spring (323) sleeved on the clamping rod (32) are fixedly provided on the clamping rod (32).

6. A high-precision current transformer for a low-voltage switch as claimed in claim 5, characterized in that: The arc-shaped clamping head (321) is provided with a threaded column (3211), and the end surface of the clamping rod (32) is adapted to be provided with an internal threaded inner hole (324).

7. A high-precision current transformer for a low-voltage switch as claimed in claim 5, characterized in that: The housing (30) is provided with at least three first through holes (301) and one second through hole (302).

8. A high-precision current transformer for a low-voltage switch according to claim 7, characterized in that: The clamping rod (32) passes through the first through hole (301) to connect to the arc-shaped clamping head (321), and the threaded rotating rod (33) passes through the second through hole (302) to connect to the internal threaded through hole (313).

9. A high-precision current transformer for a low-voltage switch according to claim 8, characterized in that: A screw cap (331) is provided at the end of the threaded screw rod (33).

10. A high-precision current transformer for a low-voltage switch according to claim 9, characterized in that: The screw cap (331) is provided with a notch (332).

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