Adjustable current transformer

Abstract

The utility model discloses an adjustable current transformer. The adjustable current transformer comprises an annular iron core, a primary side winding is wound on one side of the annular iron core, and a plurality of secondary side windings with different winding turns are wound on the other side of the annular iron core; the first end of each secondary side winding is connected with a first conducting strip, and the second end of each secondary side winding is connected with a second conducting strip; the first conducting strips are arranged on the left side of the supporting plate, and the second conducting strips are arranged on the right side of the supporting plate. A movable plate is arranged above the supporting plate, and two third conducting strips are arranged at the bottom of the movable plate; the supporting plate is connected with a driving mechanism; the two third conducting strips are electrically connected with a measuring circuit used for being connected with a measuring instrument or a protection loop. According to the adjustable current transformer, the current ratio can be rapidly adjusted according to needs, and the current ratio can be adjusted.

Description

Technical Field

[0001] The utility model relates to a current transformer, in particular to an adjustable current transformer. Background Art

[0002] The current transformer is an instrument that converts a large primary current into a small secondary current for measurement based on the principle of electromagnetic induction. The current transformer is composed of a closed iron core and a winding. Its primary winding has very few turns and is connected in series in the circuit of the current to be measured, so it often has the entire current of the circuit flowing through it. The secondary winding has more turns and is connected in series in the measuring instrument and the protection circuit. When the current transformer is working, its secondary circuit is closed, so the impedance of the series coil of the measuring instrument and the protection circuit is very small, and the working state of the current transformer is close to a short circuit. When the number of turns of the primary winding remains unchanged, the current of the secondary winding is related to the number of turns of the secondary winding. When the current of the secondary winding needs to be adjusted according to different measurement needs, and adjusting the current of the secondary winding requires adjusting the number of turns of the secondary winding. Therefore, an adjustable current transformer is needed.

[0003] For example, Chinese patent CN202322040687.9 discloses a current transformer with anti-interference, which includes a housing, a winding and a connecting wire. The housing is equipped with a winding, and the winding side is equipped with a connecting wire. The connecting wire is mounted on both sides of the housing. The housing is equipped with a maintenance structure, and the housing side is equipped with a connecting structure. The maintenance structure includes an assembly base, which is fixed to the bottom of the housing, and an assembly ring is provided on the upper side of the assembly base. A maintenance cover is inserted on the top of the assembly ring, and the maintenance cover is completely covered on the outside of the housing. The number of windings of the primary winding and the secondary winding in this current transformer is fixed, the current in the secondary winding is difficult to adjust, and the current ratio is not adjustable, which has great limitations in use. Summary of the invention

[0004] The utility model aims to provide an adjustable current transformer, which can quickly adjust the current ratio according to the needs to achieve the adjustable current ratio.

[0005] In order to achieve the above-mentioned purpose, the utility model provides an adjustable current transformer, including a ring-shaped iron core; a primary winding is wound on one side of the ring-shaped iron core, and a plurality of secondary windings with different numbers of winding turns are wound on the other side; the first end of each of the secondary windings is connected to a first conductive sheet, and the second end of each of the secondary windings is connected to a second conductive sheet; a plurality of the first conductive sheets are arranged on the left side of a support plate, and a plurality of the second conductive sheets are arranged on the right side of the support plate; the spacing between two adjacent first conductive sheets is the same as the spacing between two adjacent second conductive sheets; a movable plate is arranged above the support plate, and two third conductive sheets are arranged at the bottom of the movable plate; the two third conductive sheets are arranged to be able to contact the first conductive sheet and the second conductive sheet on the same secondary winding respectively; the support plate is connected to a driving mechanism for driving it to move and enabling the two third conductive sheets to switch and connect different secondary windings; the two third conductive sheets are electrically connected to a measuring circuit for connecting a measuring instrument or a protection circuit.

[0006] Preferably, the support plate is fixed in the cover shell, the movable plate is arranged above the support plate, and a plurality of vertical grooves with openings facing downwards are evenly spaced at the rear end of the movable plate. A motor is installed at the rear end of the cover shell, the shaft of the motor extends into the cover shell and is installed with a cam, and a lever parallel to the shaft and capable of extending into the vertical groove is provided at the far end of the cam.

[0007] Preferably, at least two guide rods are arranged above the movable plate in the housing, guide blocks are slidably sleeved on the guide rods, and the guide blocks are connected to the movable plate via a plurality of elastic telescopic rods.

[0008] Preferably, a spring wire electrically connected to the two third conductive sheets respectively is arranged between the movable plate and the guide block, a conductive sleeve electrically connected to the two spring wires respectively is arranged at the upper end of the guide block, a conductive strip is slidably inserted into the conductive sleeve, and the conductive strip extends to the outside of the cover and is electrically connected to a measuring instrument or a protection circuit.

[0009] Preferably, a strip plate is fixedly connected to the rear end of the movable plate, the bottom surface of the strip plate is higher than the bottom surface of the movable plate, the vertical groove is arranged at the bottom of the strip plate, and the spacing between two adjacent vertical grooves is the same as the spacing between two adjacent first conductive sheets or two adjacent second conductive sheets.

[0010] Preferably, the elastic telescopic rod includes a sleeve fixed to the bottom side of the guide block, a movable rod fixed to the upper surface of the movable plate is slidably arranged in the sleeve, a return spring is connected to the top of the movable rod, and the return spring is connected to the bottom surface of the guide block.

[0011] Preferably, a protective shell is provided at the upper end of the cover shell, the annular iron core is arranged in the protective shell, both ends of the primary winding are arranged through one side of the protective shell, and both ends of the secondary winding are arranged through the other side of the protective shell.

[0012] Preferably, a mounting plate is provided on the outer side of the cover shell, and a plurality of mounting holes are provided on the mounting plate.

[0013] According to the above technical scheme, the utility model provides an adjustable current transformer, including a ring-shaped iron core; a primary winding is wound on one side of the ring-shaped iron core, and a plurality of secondary windings with different numbers of winding turns are wound on the other side; the first end of each of the secondary windings is connected to a first conductive sheet, and the second end of each of the secondary windings is connected to a second conductive sheet; a plurality of the first conductive sheets are arranged on the left side of a support plate, and a plurality of the second conductive sheets are arranged on the right side of the support plate; the spacing between two adjacent first conductive sheets is the same as the spacing between two adjacent second conductive sheets; a movable plate is arranged above the support plate, and two third conductive sheets are arranged at the bottom of the movable plate; the two third conductive sheets are arranged to be able to contact the first conductive sheet and the second conductive sheet on the same secondary winding respectively; the support plate is connected to a driving mechanism for driving it to move and enabling the two third conductive sheets to switch and connect different secondary windings; the two third conductive sheets are electrically connected to a measuring circuit for connecting a measuring instrument or a protection circuit.

[0014] The principle and beneficial effects of the adjustable current transformer are as follows: the driving mechanism drives the support plate to move, so that the two third conductive plates arranged on the movable plate switch to connect the first conductive plates and the second conductive plates at the two ends of different secondary windings, so that the measuring instrument or the protection circuit switches different secondary windings. Since the number of winding turns of each secondary winding is different, the current ratio can be adjusted.

[0015] Other features and advantages of the present invention will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention, but do not constitute a limitation to the present invention. In the accompanying drawings:

[0017] Figure 1 It is a circuit schematic diagram of a preferred implementation of an adjustable current transformer;

[0018] Figure 2 It is a structural schematic diagram of a preferred implementation of an adjustable current transformer;

[0019] Figure 3 yes Figure 2 A structural diagram from another perspective;

[0020] Figure 4 This is a schematic diagram of the structure of the adjustable current transformer after the top is removed;

[0021] Figure 5 It is a schematic diagram of the structure of the adjustable current transformer after the side portion is removed;

[0022] Figure 6 It is a schematic diagram of a top view of a preferred embodiment of an adjustable current transformer;

[0023] Figure 7 yes Figure 6 AA cross-sectional structural diagram;

[0024] Figure 8 yes Figure 6 Schematic diagram of the BB cross-section structure.

[0025] Description of Reference Numerals

[0026] 1-annular core; 2-primary winding; 3-secondary winding; 4-first conductive sheet; 5-second conductive sheet; 6-third conductive sheet; 7-measuring circuit; 8-measuring instrument or protection circuit; 9-cover; 10-protective shell; 11-motor; 12-mounting plate; 13-mounting hole; 14-conductive strip; 15-conductive sleeve; 16-guide block; 17-guide rod; 18-support plate; 19-elastic telescopic rod; 20-spring wire; 21-strip plate; 22-movable plate; 23-vertical slot; 24-axis; 25-cam; 26-shift rod; 27-reset spring; 28-sleeve; 29-movable rod. DETAILED DESCRIPTION

[0027] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0028] In the present utility model, unless otherwise stated, directional words contained in terms such as "up, down, left, right, front, back, inside, outside" merely represent the orientation of the terms in normal usage, or are common names understood by those skilled in the art, and should not be regarded as limitations on the terms.

[0029] See also Figure 1-8The adjustable current transformer shown includes a ring-shaped iron core 1; a primary winding 2 is wound on one side of the ring-shaped iron core 1, and a plurality of secondary windings 3 with different numbers of winding turns are wound on the other side; a first end of each secondary winding 3 is connected to a first conductive sheet 4, and a second end of each secondary winding 3 is connected to a second conductive sheet 5; a plurality of the first conductive sheets 4 are arranged on the left side of a support plate 18, and a plurality of the second conductive sheets 5 are arranged on the right side of the support plate 18; the spacing between two adjacent first conductive sheets 4 is the same as the spacing between two adjacent second conductive sheets 5; a movable plate 22 is arranged above the support plate 18, and two third conductive sheets 6 are arranged at the bottom of the movable plate 22; the two third conductive sheets 6 are arranged to be able to contact the first conductive sheet 4 and the second conductive sheet 5 on the same secondary winding 3 respectively; the support plate 18 is connected to a driving mechanism for driving it to move and enable the two third conductive sheets 6 to switch and connect different secondary windings 3; the two third conductive sheets 6 are electrically connected to a measuring circuit 7 for connecting a measuring instrument or a protection circuit 8.

[0030] Through the implementation of the above technical solution, the driving mechanism in the adjustable current transformer drives the support plate 18 to move, so that the two third conductive plates 6 arranged on the movable plate 22 switch to connect the first conductive plates 4 and the second conductive plates 5 at the two ends of different secondary windings 3, so that the measuring instrument or the protection circuit 8 switches different secondary windings 3. Since the number of windings of each secondary winding 3 is different, the current ratio can be adjusted. Figure 1 As shown, taking three secondary windings 3 as an example, the distance between the three first conductive sheets 4 from top to bottom is 2 cm, the three first conductive sheets 4 are respectively the first ends of the three secondary windings 3, the distance between the three second conductive sheets 5 is 2 cm, the three second conductive sheets 5 are respectively the second ends of the three secondary windings 3, and the distance between the two third conductive sheets 6 is 10 cm.

[0031] During operation, when one of the third conductive sheets 6 contacts the first end of the first secondary winding 3, the other third conductive sheet 6 contacts the second end of the first secondary winding 3; when one of the third conductive sheets 6 contacts the first end of the second secondary winding 3, the other third conductive sheet 6 contacts the second end of the second secondary winding 3; when one of the third conductive sheets 6 contacts the first end of the third secondary winding 3, the other third conductive sheet 6 contacts the second end of the third secondary winding 3.

[0032] In this embodiment, in order to further provide a driving method for the movable plate 22, the support plate 18 is fixedly connected to the cover shell 9, the movable plate 22 is arranged above the support plate 18, and the rear end of the movable plate 22 is evenly spaced with a plurality of vertical grooves 23 with openings facing downward. The rear end of the cover shell 9 is equipped with a motor 11, the shaft 24 of the motor 11 extends into the cover shell 9 and is equipped with a cam 25, and the far end of the cam 25 is provided with a lever 26 parallel to the shaft 24 and capable of extending into the vertical groove 23. The working process is as follows: the motor 11 drives the cam 25 to rotate, driving the lever 26 to revolve around the shaft 24. When the lever 26 moves upward to the vertical slot 23, the limiting effect of the vertical slot 23 pushes the movable plate 22 to move horizontally for a certain distance. As the lever 26 continues to revolve, the lever 26 moves downward and drives out of the vertical slot 23. At this time, the movable plate 22 stops moving, and the two third conductive sheets 6 fall on the first conductive sheet 4 and the second conductive sheet 5 at both ends of the other secondary winding 3 respectively.

[0033] In this embodiment, at least two guide rods 17 are arranged above the movable plate 22 in the housing 9, and a guide block 16 is slidably sleeved on the guide rod 17, and the guide block 16 is connected to the movable plate 22 via a plurality of elastic telescopic rods 19. Through such an arrangement, the guide rod 17 provides a lateral guiding effect on the guide block 16, so that the lateral movement of the movable plate 22 is more stable. In addition, the top of the vertical groove 23 is set to be lower than the highest position of the lever 26. When the lever 26 reaches the highest position, the movable plate 22 is lifted up by a certain distance, and the distance can be controlled between 3-10 mm, so that the third conductive sheet 6 is separated from the first conductive sheet 4 and the second conductive sheet 5, and the wear between the third conductive sheet 6 and the first conductive sheet 4 and the second conductive sheet 5 is reduced.

[0034] In this embodiment, in order to further provide a way of connecting the third conductive sheet 6 to the outside, a spring wire 20 electrically connected to the two third conductive sheets 6 is provided between the movable plate 22 and the guide block 16, and a conductive sleeve 15 electrically connected to the two spring wires 20 is provided at the upper end of the guide block 16, and a conductive strip 14 is slidably inserted into the conductive sleeve 15, and the conductive strip 14 extends to the outside of the cover 9 and is electrically connected to the measuring instrument or the protection circuit 8. The spring wire 20 is a spiral structure with elastic expansion and contraction performance to adapt to the vertical movement of the movable plate 22. Two spring wires 20 are provided, and the lower ends of the spring wires 20 pass through the movable plate 22 and are electrically connected to the two third conductive sheets 6 respectively. The upper end of the spring wire 20 passes through the guide block 16 and is electrically connected to the conductive sleeve 15. Two conductive sleeves 15 are also correspondingly provided, and are electrically connected to the two spring wires 20 respectively. The conductive strip 14 is slidably inserted into the conductive sleeve 15 and is slidably electrically connected to the conductive sleeve 15, which can overcome the influence of the left and right sliding of the guide block 16. Two conductive strips 14 are also correspondingly provided with the conductive sleeves 15, and are fixedly connected to the side wall of the cover shell 9.

[0035] In this embodiment, the rear end of the movable plate 22 is fixedly connected to a strip plate 21, the bottom surface of the strip plate 21 is higher than the bottom surface of the movable plate 22, the vertical slot 23 is arranged at the bottom of the strip plate 21, and the distance between two adjacent vertical slots 23 is the same as the distance between two adjacent first conductive sheets 4 or two adjacent second conductive sheets 5. Through such an arrangement, the position of the vertical slot 23 is raised, so that the installation height of the motor 11 can be increased, and the problem of occupying a large space when the lever 26 is rotated to the bottom position is overcome.

[0036] In this embodiment, in order to further provide an elastic telescopic rod 19, the elastic telescopic rod 19 includes a sleeve 28 fixed to the bottom side of the guide block 16, a movable rod 29 fixed to the upper surface of the movable plate 22 is slidably arranged in the sleeve 28, and a reset spring 27 is connected to the top of the movable rod 29, and the reset spring 27 is connected to the bottom surface of the guide block 16. The movable rod 29 can squeeze the reset spring 27 in the sleeve 28, and the movable rod 29 can be reset by the reset spring 27 when the movable rod 29 is not subjected to external force. After the reset spring 27 is reset, the third conductive sheet 6 can be stably pressed and contacted on the first conductive sheet 4 or the second conductive sheet 5.

[0037] In this embodiment, in order to further provide an installation method for the annular iron core 1, a protective shell 10 is provided at the upper end of the cover shell 9, the annular iron core 1 is arranged in the protective shell 10, the two ends of the primary side winding 2 are arranged through one side of the protective shell 10, and the two ends of the secondary side winding 3 are arranged through the other side of the protective shell 10.

[0038] In this embodiment, a mounting plate 12 is disposed outside the housing 9, and a plurality of mounting holes 13 are disposed on the mounting plate 12. With such a configuration, it is convenient to mount the adjustable current transformer at a corresponding mounting position in the use scenario by bolts.

[0039] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, and these simple modifications all belong to the protection scope of the present invention.

[0040] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present utility model will not further describe various possible combinations.

[0041] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. An adjustable current transformer, characterized in that: The adjustable current transformer comprises a ring-shaped iron core (1); A primary winding (2) is wound on one side of the annular iron core (1), and a plurality of secondary windings (3) with different numbers of winding turns are wound on the other side; The first end of each secondary winding (3) is connected to a first conductive sheet (4), and the second end of each secondary winding (3) is connected to a second conductive sheet (5); A plurality of the first conductive sheets (4) are arranged on the left side of the support plate (18), and a plurality of the second conductive sheets (5) are arranged on the right side of the support plate (18); The distance between two adjacent first conductive sheets (4) is the same as the distance between two adjacent second conductive sheets (5); A movable plate (22) is arranged above the support plate (18), and two third conductive sheets (6) are arranged at the bottom of the movable plate (22); The two third conductive sheets (6) are arranged to be able to respectively contact the first conductive sheet (4) and the second conductive sheet (5) on the same secondary winding (3); The support plate (18) is connected to a driving mechanism for driving the support plate (18) to move and enable the two third conductive sheets (6) to switch and connect to different secondary windings (3); The two third conductive sheets (6) are electrically connected to a measuring circuit (7) for connecting a measuring instrument or a protection circuit (8).

2. The adjustable current transformer according to claim 1, characterized in that: The support plate (18) is fixed in the cover shell (9), the movable plate (22) is arranged above the support plate (18), and a plurality of vertical grooves (23) with openings facing downwards are arranged at equal intervals at the rear end of the movable plate (22). A motor (11) is installed at the rear end of the cover shell (9), the shaft (24) of the motor (11) extends into the cover shell (9) and is installed with a cam (25), and a lever (26) parallel to the shaft (24) and capable of extending into the vertical groove (23) is arranged at the far end of the cam (25).

3. The adjustable current transformer according to claim 2, characterized in that: At least two guide rods (17) are arranged above the movable plate (22) in the housing (9), a guide block (16) is slidably sleeved on the guide rod (17), and the guide block (16) is connected to the movable plate (22) via a plurality of elastic telescopic rods (19).

4. The adjustable current transformer according to claim 3, characterized in that: A spring conductor (20) electrically connected to the two third conductive sheets (6) is arranged between the movable plate (22) and the guide block (16); a conductive sleeve (15) electrically connected to the two spring conductors (20) is arranged at the upper end of the guide block (16); a conductive strip (14) is slidably inserted into the conductive sleeve (15); the conductive strip (14) extends to the outside of the cover (9) and is electrically connected to a measuring instrument or a protection circuit (8).

5. The adjustable current transformer according to claim 2, characterized in that: A strip plate (21) is fixedly connected to the rear end of the movable plate (22); the bottom surface of the strip plate (21) is higher than the bottom surface of the movable plate (22); the vertical groove (23) is arranged at the bottom of the strip plate (21); and the spacing between two adjacent vertical grooves (23) is the same as the spacing between two adjacent first conductive sheets (4) or two adjacent second conductive sheets (5).

6. The adjustable current transformer according to claim 3, characterized in that: The elastic telescopic rod (19) comprises a sleeve (28) fixedly connected to the bottom side of the guide block (16), a movable rod (29) fixedly connected to the upper surface of the movable plate (22) is slidably arranged in the sleeve (28), a return spring (27) is connected to the top of the movable rod (29), and the return spring (27) is connected to the bottom surface of the guide block (16).

7. The adjustable current transformer according to claim 2, characterized in that: A protective shell (10) is arranged at the upper end of the cover shell (9), the annular iron core (1) is arranged in the protective shell (10), the two ends of the primary winding (2) are arranged through one side of the protective shell (10), and the two ends of the secondary winding (3) are arranged through the other side of the protective shell (10).

8. The adjustable current transformer according to claim 2, characterized in that: A mounting plate (12) is arranged on the outside of the cover shell (9), and a plurality of mounting holes (13) are arranged on the mounting plate (12).

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