Current transformer
The current transformer, with its hinged housing structure and plastic pre-tightening design, solves the problems of cable wear and high cost, and achieves a compact, convenient, and highly accurate current transformer.
Patent Information
- Application Number
- CN202520095329.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-15
- Publication Date
- 2026-02-06
- Estimated Expiration
- 2035-01-15
AI Technical Summary
Existing current transformers suffer from cable surface wear and gaps in the detection port during testing, and their integrated structure leads to high mold and injection molding costs.
It adopts a hinged structure of lower and upper cover of the outer shell, and has an upper and lower magnetic core inside. The elasticity of the plastic shell is used to apply a pre-tightening force to the magnetic core, and the cable to be tested is fixed by the wire buckle, which can adapt to the testing of cables of different diameters.
This invention enables a current transformer that is compact, easy to test, and low in cost, improving the sensitivity and measurement accuracy of the transformer while reducing mold and injection molding costs.
Smart Images
Figure CN223884236U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a current transformer especially relates to a current transformer which is compact in structure, convenient to detect and low in cost. BACKGROUND
[0002] The current transformer is an instrument for converting primary side large current into secondary side small current to measure, and is composed of a closed iron core and winding, and the primary side winding has few turns and is connected in series in the current line to be measured, so that the whole current of the line flows through it, and the secondary winding has many turns and is connected in series in the measuring instrument and protection circuit, and the secondary circuit of the current transformer is always closed during operation, so that the impedance of the series coil of the measuring instrument and protection circuit is very small, and the working state of the current transformer is close to short circuit.
[0003] The current transformer is an instrument for converting primary side large current into secondary side small current to measure, and is composed of a closed iron core and winding, and the primary side winding has few turns and is connected in series in the current line to be measured, so that the whole current of the line flows through it, and the secondary winding has many turns and is connected in series in the measuring instrument and protection circuit, and the secondary circuit of the current transformer is always closed during operation, so that the impedance of the series coil of the measuring instrument and protection circuit is very small, and the working state of the current transformer is close to short circuit. SUMMARY
[0004] The utility model solves the technical problem that a current transformer is provided, which is compact in structure, convenient to detect and low in cost.
[0005] To solve the above technical problems, the technical scheme of the utility model is as follows: a current transformer, which is characterized by comprising a lower shell cover, an upper shell cover hinged to the lower shell cover, an upper computer lead arranged below the lower shell cover, a lower magnetic core arranged in the lower shell cover, a framework through which the lower magnetic core passes, a coil arranged on the framework, a PCB board arranged on the framework and connected with the coil and the upper computer lead respectively, and an upper magnetic core arranged in the upper shell cover, wherein the upper shell cover and the lower shell cover form a complete shell in use, and the upper magnetic core directly adheres to the lower magnetic core to form a complete magnetic core in use.
[0006] The upper magnetic core and the lower magnetic core form a detection port through which the cable to be detected passes in use, and the detection port comprises an upper detection port on the upper magnetic core and a lower detection port on the lower magnetic core; the upper shell cover and the lower shell cover form a shell port through which the cable to be detected passes in use, and the shell port comprises an upper shell port on the upper shell cover and a lower shell port on the lower shell cover, and the center of the detection port coincides with that of the shell port.
[0007] Preferably, the hinge between the lower cover and the upper cover of the shell is a hinge connection, the average thickness of the hinge is 0.2-0.3mm, and the outer thickness of the hinge is 0.2-0.3mm thicker than the middle hinge.
[0008] Preferably, the upper cover of the shell is provided with a first partition plate and a second partition plate arranged in parallel, the first partition plate and the second partition plate form an upper accommodating cavity for embedding the upper magnetic core, and the upper magnetic core is interference fit or transition fit in the upper accommodating cavity.
[0009] Preferably, the first partition plate and the second partition plate are both provided with a first clamping hook towards the upper magnetic core, and the first clamping hook is a plastic elastic piece.
[0010] Preferably, the upper accommodating cavity is provided with an elastic plastic piece at the bottom of the upper accommodating cavity, and the elastic plastic piece provides a downward pre-tightening force after the upper magnetic core is embedded in the upper accommodating cavity.
[0011] Preferably, the lower cover of the shell is provided with a lower accommodating cavity for placing the lower magnetic core, the skeleton, the coil and the PCB board, the lower cover of the shell is provided with a supporting part in direct contact with the bottom of the lower magnetic core, the supporting part is horizontally arranged, and the PCB board is located below the supporting part.
[0012] Preferably, the lower cover of the shell is provided with a second clamping hook located in the lower accommodating cavity, the second clamping hook is provided with a hook structure abutting against the top of the skeleton, and the second clamping hook is a plastic elastic piece.
[0013] Preferably, the non-hinged side of the lower cover and the upper cover of the shell is provided with a buckle structure, the buckle structure includes a clamping part provided on the upper cover of the shell and a protruding part provided on the lower cover of the shell, and when the upper cover of the shell is attached to the lower cover of the shell, the clamping part is buckled on the protruding part.
[0014] Preferably, the upper cover and the lower cover of the shell are provided with a wire buckle for fixing the cable to be detected, the wire buckle includes an upper wire buckle fixing frame provided on the upper cover of the shell and a lower wire buckle fixing frame provided on the lower cover of the shell, and the upper wire buckle fixing frame is buckled on the lower wire buckle fixing frame after the cable to be detected passes through.
[0015] The current transformer of the utility model has the advantages that: through the above structure, the current transformer is formed by hinging the upper shell cover and the lower shell cover, the upper magnetic core is arranged in the upper shell cover, the lower magnetic core is arranged in the lower shell cover, the cable to be detected is passed through the shell opening and the detection opening on the shell, and the cable to be detected is fixed by using the wire buckle. BRIEF DESCRIPTION OF DRAWINGS
[0016] The utility model will be further explained in detail in combination with the drawings and specific embodiments.
[0017] Figure 1 It is a perspective view of the current transformer in the use state of the utility model.
[0018] Figure 2 It is a structure schematic view of the current transformer in the use state of the utility model.
[0019] Figure 3 It is a sectional view of the current transformer in the use state of the utility model (omitting the cable).
[0020] Figure 4 It is a perspective view of the upper shell cover and the lower shell cover in the current transformer of the utility model in the open state.
[0021] Figure 5 It is a perspective exploded view of the upper shell cover, the lower shell cover, the upper magnetic core and the lower magnetic core in the current transformer of the utility model in the open state.
[0022] Figure 6 It is a structure schematic view of the upper shell cover and the lower shell cover in the current transformer of the utility model in the open state.
[0023] Figure 7 It is a bottom view of the upper shell cover and the lower shell cover in the current transformer of the utility model in the open state.
[0024] Figure 8 It is a structure schematic view of the coil, the framework and the lower magnetic core in the current transformer of the utility model.
[0025] In the figure: 1 - the lower cover of the shell, 11 - the lower containing cavity, 12 - the supporting part, 13 - the second clamping hook, 2 - the upper cover of the shell, 21 - the first partition, 22 - the second partition, 23 - the upper containing cavity, 24 - the first clamping hook, 25 - the elastic plastic part, 3 - the upper machine lead, 4 - the lower magnetic core, 5 - the framework, 6 - the coil, 7 - the PCB board, 8 - the upper magnetic core, 9 - the detection port, 10 - the shell port, 15 - the cable to be detected, 16 - the clamping part, 17 - the protruding part, 18 - the upper fixing frame of the wire buckle, 19 - the lower fixing frame of the wire buckle. DETAILED DESCRIPTION
[0026] The current transformer of the utility model includes the lower cover of the shell 1, the upper cover of the shell 2 articulated with the lower cover of the shell 1, the upper machine lead 3 arranged below the lower cover of the shell 1, the lower magnetic core 4 arranged in the lower cover of the shell 1, the framework 5 for the lower magnetic core 4 to pass through, the coil 6 arranged on the framework 5, the PCB board 7 arranged on the framework 5 and connected with the coil 6 and the upper machine lead 3 respectively, the upper magnetic core 8 arranged in the upper cover of the shell 2, the upper cover of the shell 2 and the lower cover of the shell 1 form a complete shell in the use state, and the upper magnetic core 8 directly adheres to the lower magnetic core 4 to form a complete magnetic core in the use state.
[0027] The upper magnetic core 8 and the lower magnetic core 4 form the detection port 9 for the cable to be detected 15 to pass through in the use state, the detection port 9 is composed of the upper detection port 9 on the upper magnetic core 8 and the lower detection port 9 on the lower magnetic core 4; the upper cover of the shell 2 and the lower cover of the shell 1 form the shell port 10 for the cable to be detected to pass through in the use state, the shell port 10 is composed of the upper shell port 10 on the upper cover of the shell 2 and the lower shell port 10 on the lower cover of the shell 1, and the center of the detection port 10 and the shell port 10 coincide.
[0028] By adopting the above structure, the current transformer is articulated by the lower cover of the shell 1 and the upper cover of the shell 2, the upper magnetic core 8 is arranged in the upper cover of the shell 2, the lower magnetic core 4 is arranged in the lower cover of the shell 1, the cable to be detected passes through the shell port 10 and the detection port 9 on the shell, and the wire buckle is used to fix the cable to be detected. Compared with the existing structure, the plastic shell is used to articulate the structure, the upper and lower covers of the shell are arranged in the same mold to save the mold and injection cost; when the transformer is used to measure the cable, the elasticity of the plastic is used to apply the pre-tightening force to the magnetic core to improve the sensitivity of the transformer, and the current transformer of the utility model can satisfy the detection of cables with different specifications and diameters.
[0029] The hinge connection between the above-mentioned lower cover of the shell 1 and the upper cover of the shell 2 is a hinge connection, the average thickness of the hinge is 0.2-0.3mm, and the outside thickness of the hinge is 0.2-0.3mm thicker than the middle hinge of the hinge. The above design can prevent the hinge from breaking from both sides during use.
[0030] The utility model discloses a shell upper cover 2 is equipped with the parallelly arranged first baffle 21 and second baffle 22, and the first baffle 21 and second baffle 22 form the upper accommodating cavity 23 for embedding the upper magnetic core 8, and the upper magnetic core 8 is in interference fit or transition fit in the upper accommodating cavity 23. The first baffle 21 and second baffle 22 are all provided with the first clamping hook 24 towards the upper magnetic core 8, and the first clamping hook 24 is a plastic elastic member. The elastic plastic member 25 is arranged at the bottom of the upper accommodating cavity 23 in the upper accommodating cavity 23, and the elastic plastic member 25 provides the pre-tightening force downward after the upper magnetic core 8 is embedded in the upper accommodating cavity 23. The elasticity of the plastic is utilized to design the first clamping hook 24, the sixth degree of freedom is limited to the downward, and the first magnetic core is fixed, when the shell lower cover 1 is clamped with the shell lower cover 1, the pre-tightening force is applied by the elastic characteristics of the elastic plastic member 25, so that the upper magnetic core 8 and the lower magnetic core 4 are in close contact, and the sensitivity and the measurement precision of the mutual inductor are improved.
[0031] The shell lower cover 1 is provided with the lower accommodating cavity 11 for placing the lower magnetic core 4, the framework 5, the coil 6 and the PCB board 7, and the shell lower cover 1 is provided with the supporting portion 12 directly contacting the bottom of the lower magnetic core 4, the supporting portion 12 is horizontally arranged, and the PCB board 7 is located below the supporting portion 12. The shell lower cover 1 is provided with the second clamping hook 13 located in the lower accommodating cavity 11, the second clamping hook 13 is provided with the hook structure abutting against the top of the framework 5, and the second clamping hook 13 is a plastic elastic member. The shell lower cover 1 is used for placing the lower magnetic core 4, the framework 5, the PCB board 7 and the coil 6, the periphery and the bottom of the shell lower cover 1 fix the fifth degree of freedom of the lower magnetic core 4, the second clamping hook 13 designed by the toughness of the plastic is utilized, the sixth degree of freedom of the lower magnetic core 4 is limited to the upward, and the lower magnetic core 4 is fixed.
[0032] The non-hinged side of the shell lower cover 1 and the shell upper cover 2 is provided with the buckle structure, the buckle structure includes the clamping portion 16 provided on the shell upper cover 2 and the protruding portion 17 provided on the shell lower cover 1, and when the shell upper cover 2 is attached to the shell lower cover 1, the clamping portion 16 is buckled on the protruding portion 17.
[0033] The shell upper cover 2 and the shell lower cover 1 are provided with the wire buckle for fixing the cable to be detected, the wire buckle includes the wire buckle upper fixing frame 18 provided on the shell upper cover 2 and the wire buckle lower fixing frame 19 provided on the shell lower cover 1, and the wire buckle upper fixing frame 18 is buckled on the wire buckle lower fixing frame 19 after the cable to be detected passes through.
[0034] The PCB board 7 is used for overvoltage and overcurrent protection, buffers the host computer, connects the lead of the induction coil 6 and the lead 3 of the host computer. The upper magnetic core 8 and the lower magnetic core 4 are ferrite or nanocrystalline, which improves the precision and sensitivity of the inductor. The framework 5 is a plastic part, and the material can be PA66, PBT, etc. According to different measurement requirements, select the appropriate material, the lower magnetic core 4 is placed in the framework 5, and the coil 6 is wound on the framework 5. According to different measurement requirements, the number of turns is selected according to the requirements. The coil 6 is an enameled wire (the base can be copper, aluminum, copper alloy) / high temperature adhesive tape. The number of turns and the size of the wire diameter, temperature rise and other parameters are determined according to the required precision of the measured object, the measurement range and the allowed peak current of the host computer.
[0035] It is to be understood that the above description is intended to be illustrative and not restrictive. Many embodiments and many applications besides the examples provided will be apparent upon reading the above description. The scope of the application should be determined, not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are incorporated by reference for the purpose of the present application. The omission of any aspect of the subject matter disclosed herein from any claim is not a disclaimer of such subject matter unless the opposite is expressly stated.
Claims
1. A current transformer characterized by: The current transformer comprises a lower shell cover, an upper shell cover hinged to the lower shell cover, an upper computer lead arranged below the lower shell cover, a lower magnetic core arranged in the lower shell cover, a skeleton through which the lower magnetic core passes, a coil arranged on the skeleton, a PCB board arranged on the skeleton and connected to the coil and the upper computer lead respectively, an upper magnetic core arranged in the upper shell cover, the upper shell cover and the lower shell cover form a complete shell in the use state, and the upper magnetic core directly adheres to the lower magnetic core to form a complete magnetic core in the use state; The upper magnetic core and the lower magnetic core form a detection port through which the cable to be detected passes in the use state, the detection port is composed of an upper detection port on the upper magnetic core and a lower detection port on the lower magnetic core; the upper shell cover and the lower shell cover form a shell port through which the cable to be detected passes in the use state, the shell port is composed of an upper shell port on the upper shell cover and a lower shell port on the lower shell cover, and the centers of the detection port and the shell port coincide.
2. A current transformer as claimed in claim 1, characterized in that: The hinge between the lower shell cover and the upper shell cover is a hinge connection, the average thickness of the hinge is 0.2-0.3mm, and the outer thickness of the hinge is 0.2-0.3mm thicker than the middle hinge of the hinge.
3. A current transformer as claimed in claim 1, characterized in that: A first partition plate and a second partition plate are arranged in parallel on the upper shell cover, the first partition plate and the second partition plate form an upper accommodating cavity for embedding the upper magnetic core, and the upper magnetic core is in interference fit or transition fit in the upper accommodating cavity.
4. A current transformer as claimed in claim 3, characterised in that: The first partition plate and the second partition plate are both provided with a first hook towards the upper magnetic core, and the first hook is a plastic elastic member.
5. A current transformer as claimed in claim 3, characterised in that: An elastic plastic member is arranged in the upper accommodating cavity at the bottom of the upper accommodating cavity, and the elastic plastic member provides a downward pre-tightening force after the upper magnetic core is embedded in the upper accommodating cavity.
6. A current transformer as claimed in claim 1, characterized in that: A lower accommodating cavity is arranged on the lower shell cover for placing the lower magnetic core, the skeleton, the coil and the PCB board, a supporting portion is arranged on the lower shell cover and directly contacts the bottom of the lower magnetic core, the supporting portion is horizontally arranged, and the PCB board is below the supporting portion.
7. A current transformer as claimed in claim 6, characterised in that: A second hook is arranged on the lower shell cover in the lower accommodating cavity, a hook structure is arranged on the second hook and abuts against the top of the skeleton, and the second hook is a plastic elastic member.
8. A current transformer as claimed in claim 1, characterized in that: A buckle structure is arranged on the non-hinged side of the lower shell cover and the upper shell cover, the buckle structure comprises a clamping portion arranged on the upper shell cover and a protruding portion arranged on the lower shell cover, and the clamping portion buckles on the protruding portion when the upper shell cover is attached to the lower shell cover.
9. A current transformer as claimed in claim 1, characterized in that: A wire buckle for fixing the cable to be detected is arranged on the upper shell cover and the lower shell cover, the wire buckle comprises an upper wire buckle fixing frame arranged on the upper shell cover and a lower wire buckle fixing frame arranged on the lower shell cover, and the upper wire buckle fixing frame buckles on the lower wire buckle fixing frame after the cable to be detected passes.