KR20220058526A - Connection structure of transformer and wiring terminal, manufacturing method thereof, and meter thereof - Google Patents

Abstract

The present invention relates to a connection structure of a transformer and a wiring terminal, a manufacturing method thereof, and a meter thereof. The connection structure includes a transformer, a primary current wire and a wiring terminal. One axial end of the wiring terminal is provided with a connection hole for connection with a primary current wire. The other axial end of the wiring terminal is provided with a wiring hole for external electrical connection. Snap teeth are provided on the inner wall of the connection hole of the wiring terminal. The transformer is sleeved over the primary current wire. The primary current wire is inserted into the connection hole, and the hardness of the snap teeth is greater than that of the primary current wire. After the connection hole of the wiring terminal is pressed by an external machine, the snap teeth are completely embedded in the primary current wire to achieve or close to zero resistance contact. This arrangement can save electrical energy, reduce the manufacturing cost of the transformer, improve the consistency of the connection, and make the use of electricity stable and reliable.

Description

Connection structure of transformer and wiring terminal, manufacturing method thereof, and meter thereof

The present invention relates to a connection structure of a transformer and a wiring terminal used in instruments and meters, a manufacturing method thereof, and a meter thereof, and in particular, a connection structure of a transformer and wiring terminal suitable for the field of electric energy transmission, a manufacturing method thereof, and to its meter.

Transformers are widely used in electronics and automatic control fields, such as communication systems, measuring or metering components. Therefore, the connection structure of the transformer and the wiring terminal is a wide market all over the world. According to incomplete statistics, annual global sales of such products exceed US$50 billion.

In existing technologies, there are commonly used methods for connecting a transformer and a wiring terminal. One method is that a step is provided at one end of the wiring terminal, a screw hole is provided in the step, and the primary current wire of the transformer is fixed directly on the step with a screw. This structure requires that the contact surface and step plane of the primary current wire be in flat and close contact, and the screws are required to be tightened in place to ensure low contact resistance, which provides poor mass production consistency. The contact resistance of this connection structure is 40 to 60 uΩ, and its own power consumption is large, which has been tested as wasting electrical energy. Another method is to directly weld the transformer covered primary current wire onto the step or side end surface. For example, the invention patent number DE10000500B4 of Bosch proposes an ammeter arrangement for electronic modules. The manganese copper resistor in the ammeter is welded directly to the sensor at the end of the shunt unit. This type of connection structure requires silver solder to be applied to the contact between the connection end of the device and the step or side end surface of the wiring terminal. The surface after welding also needs to be cleaned and treated with oxidation resistance. In particular, when the surface of the wiring terminal is electroplated, the electroplated layer is sometimes separated from the base material under high-temperature welding, causing loosening and deterioration, which affects the normal use of the device. If there is dust on the surface of the wiring terminal, and there is a wrong welding in the welding place, it is difficult to achieve consistency in the welding hot melt process. For example, when it is used as a structure for measuring, weighing, and controlling, its accuracy and stability are not high enough.

Therefore, in the field of electric power, especially under strict requirements related to the safety of the general public, how to optimize the electrical connection between the transformer and the wiring terminal is an urgent problem to be studied and solved by those skilled in the art.

One object of the present invention is to provide a stable and reliable connection structure of a transformer and a wiring terminal, a method for manufacturing the connection structure, and a meter of the connection structure, thereby saving electrical energy, reducing the manufacturing cost of the transformer, and improving the consistency of the connection is to improve

In order to achieve the above technical object, the present invention adopts the following technical solution: A connection structure of a transformer and a wiring terminal, wherein the connection structure includes the transformer, the primary current wire and the wiring terminal. One axial end of the wiring terminal is provided with a connection hole for connection with the primary current wire, and the other axial end of the wiring terminal is provided with a wiring hole for external electrical connection, the connection hole of the wiring terminal Snap teeth are provided on the inner sidewall of the The transformer is sheathed on the primary current wire. the primary current wire is inserted into the connecting hole, the hardness of the snap teeth is greater than that of the primary current wire, and the snap teeth are inserted into the primary current wire after the connecting hole of the wiring terminal is pressed by an external machine is completely embedded in to achieve or approximate zero ohmic contact.

As a further improvement of the present invention, the hardness of the primary current wire is 70±10 Vickers after the primary current wire is subjected to hardness reduction treatment.

As a further improvement of the present invention, the primary current wire is annealed using copper as a raw material, and the copper is annealed to a hardness of 70±10 Vickers.

As a further improvement of the present invention, the primary current wire is annealed using brass as a raw material, and the brass is annealed to a hardness of 70±10 Vickers.

As a further improvement of the present invention, the primary current wire is annealed using aluminum or an aluminum alloy as a raw material, and the aluminum or the aluminum alloy is annealed to a hardness of 70±10 Vickers.

As a further improvement of the present invention, the hardness of the snap tooth is 140 Vickers to 170 Vickers.

As a further improvement of the present invention, the hardness of the wiring terminal is 140 Vickers to 170 Vickers.

As a further improvement of the present invention, the wiring terminals are made of H55-H68 brass material.

As a further improvement of the present invention, the wiring terminal is provided with a wiring fastening screw hole communicating with the wiring hole in a radial direction, the wiring hole being used for inserting an external power input/output wire, and the wiring fastening screw holes are Used for screwing and fixing the external power input/output wire, the wiring terminal is provided with a fixing screw hole for fixing with the meter housing in a radial direction, and the connection hole and the wiring hole are opposite and do not communicate with each other.

As a further refinement of the invention, the snap teeth are helical threads.

As a further improvement of the present invention, the wiring terminal is provided with a main body and a columnar body located at the front end of the main body, and the connecting hole is recessed rearwardly from the front end of the columnar body, the outside of the columnar body The surface is contracted inward after being pressed by the external machine.

As a further development of the invention, the outer surface of the columnar body becomes polygonal after being pressed by the outer machine.

As a further improvement of the present invention, the diameter of the primary current wire is ?3.5 mm to ?6.0 mm, and the diameter of the threads of the connection hole is M4.0 mm to M7.0 mm.

As a further improvement of the present invention, the outer diameter of the columnar body is ?7.0 mm to ?12.5 mm.

As a further refinement of the present invention, the depth of the connecting hole is between 10.0 mm and 8.0 mm.

As a further improvement of the present invention, a contact resistance connecting the wiring terminal and the primary current wire is 0 uΩ to 5 uΩ.

As a further refinement of the invention, the primary current wire has a curved cylindrical shape.

As a further improvement of the present invention, the primary current wire has two ends, each of which is inserted into the wiring terminal.

As a further refinement of the invention, the transformer is a current transformer, a voltage transformer or a power sensor.

In order to achieve the above technical object, the present invention also adopts the following technical solution: A meter, comprising a metering device, a metering display device, and a meter housing having the above-described connection structure of the transformer and the wiring terminal.

In order to achieve the above technical object, the present invention also adopts the following technical solution: A method for manufacturing the above-described connection structure of a transformer and a wiring terminal, comprising:

A step A of manufacturing the wiring terminal and forming the connection hole on the wiring terminal and snap teeth positioned in the connection hole;

B manufacturing the primary current wire, annealing the primary current wire to make the hardness of the snap teeth greater than that of the primary current wire;

a step C of inserting the primary current wire into a connection hole of the wiring terminal, so that the snap teeth are arranged outside the primary current wire; and

a step D of performing an external mechanical operation for pressing the wiring terminal so that the snap teeth of the connection hole are embedded into the primary current wire to achieve or close to zero resistance contact;

includes

As a further improvement of the present invention, the wiring terminal is formed of a columnar body, the connecting hole is formed by recessing from the columnar body, and the snap teeth in the connecting hole are manufactured in a thread shape extending along the front-rear direction. .

As a further improvement of the present invention, the diameter of the primary current wire is Φ3.5 mm, the diameter of the threads of the connection hole is M4.0 mm, the depth of the connection hole is 10.0 mm, and the outside of the columnar body is The diameter is ?7.0 mm to ?8.5 mm, and the contact resistance connecting the wiring terminal and the primary current wire is 0 u? to 5 u?.

As a further improvement of the present invention, the diameter of the primary current wire is Φ5.0 mm, the diameter of the threads of the connection hole is M6.0 mm, the depth of the connection hole is 9.0 mm, and the outside of the columnar body is The diameter is ?8.5 mm to ?10.0 mm, and the contact resistance connecting the wiring terminal and the primary current wire is 0 u? to 5 u?.

As a further improvement of the present invention, the diameter of the primary current wire is Φ6.0 mm, the diameter of the threads of the connection hole is M7.0 mm, the depth of the connection hole is 8.0 mm, and the outside of the columnar body is The diameter is ?10.5 mm to ?12.5 mm, and the contact resistance connecting the wiring terminal and the primary current wire is 0 u? to 5 u?.

Compared with the prior art, the hardness of the snap teeth on the inner sidewall of the connection hole of the wiring terminal according to the present invention is greater than that of the primary current wire. After the connection hole of the wiring terminal is pressed by an external machine, the snap teeth are fully embedded with the primary current wire to achieve or approach a zero resistance contact. In this arrangement, when an external mechanical pressure presses and contracts the connecting hole, a snap tooth having a greater hardness on the inner wall of the connecting hole can be easily embedded into a primary current wire having a smaller hardness, between the two Achieve almost complete seamless contact. On the other hand, the complete embedding of snap teeth can further increase the contact area between the primary current wire and the connecting hole in the radial direction. On the other hand, the axial limiting effect of the snap teeth can effectively prevent the primary current wire from being pressed and extended in the axial direction. In this way, the contact resistance of the connection between the primary current wire and the wiring terminal can be reduced, and the contact resistance is almost zero. This is the best choice for ensuring the stability of the working state of the connection structure, which reduces power consumption and saves energy resources. At the same time, the manufacturing cost of the transformer and the primary current wire can be reduced, and the connection consistency of mechanical pressure is stable and reliable.

1 is a schematic diagram of a wiring terminal according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the wiring terminal of FIG. 1 .
3 is a structural schematic diagram of a connection structure of a transformer and a wiring terminal of the present invention before assembly.
4 is a schematic diagram of a connection structure of a transformer and a wiring terminal of the present invention after assembly.
5 is a structural schematic diagram of a connection structure of a transformer and a wiring terminal of the present invention when installed in a wiring terminal box of a meter;
6 is an exploded view of the connection structure of the transformer of the present invention.
7 is a schematic diagram of the framework of the power meter of the present invention.
Reference symbols:
Connection structure of transformer and wiring terminals: 100
Transformer: 1 Plastic case: 11
Magnetic core: 12 Middle hole: 13
Secondary Current Wire: 14 Lead Wire: 15
Primary Current Wire: 2 Wire Terminals: 3
Body: 31 Front end surface: 311
Rear end surface: 312 Flat: 313
Arc surface: 314 Wiring hole: 315
Wiring fastening screw hole: 316 Fixing screw hole: 317
Columnar body: 32 Connection hole: 321
Inner sidewall: 322 Snap teeth: 323
Wiring terminal box: 4 Screws: 5
Meter: 40 Meter housing: 41
Weighing unit: 42 Weighing display unit: 43

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless specifically indicated otherwise, the relative arrangement of components and steps, numerical expressions, and numerical values presented in these examples do not limit the scope of the present invention.

The following description of at least one exemplary embodiment is merely exemplary in nature and in no way serves as any limitation on the invention and its application or use.

Techniques and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques and equipment should be considered part of the specification.

In all examples shown and discussed herein, any particular value should be construed as illustrative only and not restrictive. Accordingly, other examples of the illustrative embodiment may have different values.

It should be noted that if a particular item is defined in one drawing, it need not be further discussed in subsequent drawings, as like reference numbers and characters indicate like items in the drawings that follow.

In the field of transformer applications, as a supplier familiar with the market demand of the industry, Weida Electronic Co., Ltd is fully aware of the problems in the existing technology. His R&D team invested more based on its own original technology, conducted long-term and large-scale experiments, program screening, and large-scale customer surveys, and finally obtained the technical solution of the present invention.

1 to 6 which are schematic structural diagrams of the connection structure 100 of the transformer 1 and the wiring terminal 3 of this invention. The connecting structure 100 of the transformer 1 and the wiring terminal 3 includes a transformer 1 , a primary current wire 2 and a wiring terminal 3 .

One axial end of the wiring terminal 3 in the axial direction is provided with a connection hole 321 for connection with the primary current wire 2 . The other axial end of the wiring terminal 3 in the axial direction is provided with a wiring hole 315 for electrical connection to the outside, such as an input/output wire (not shown). Snap teeth 323 are provided on the inner sidewall 322 of the connection hole 321 of the wiring terminal 3 .

The transformer 1 is sleeved on the primary current wire 2 .

The primary current wire 2 is inserted into the connection hole 321 , and the hardness of the snap teeth 323 is greater than that of the primary current wire 2 . After the connection hole 321 of the wiring terminal 3 is pressed by an external machine, the snap tooth 323 is completely embedded in the primary current wire 2 to achieve or close to the zero resistance contact.

In this arrangement, when the connecting hole 321 is pressed and contracted by an external mechanical pressure, the snap tooth 323 having a higher hardness on the inner sidewall 322 of the connecting hole 321 has a lower hardness. It can be easily embedded in the primary current wire 2 , thereby achieving an almost perfect seamless contact between the two. In the complete embedding of the snap tooth 323 in the primary current wire 2, on the other hand, it can further increase the contact area between the primary current wire 2 and the connecting hole 321 in the radial direction; On the other hand, the axial limiting effect of the snap teeth 323 can effectively prevent the primary current wire 2 from being squeezed to extend along the axial direction. In this way, the contact resistance of the connection between the primary current wire 2 and the wiring terminal 3 can be reduced, and the contact resistance is almost zero. This is the best choice for ensuring the stability of the working state of the connection structure, which reduces power consumption and saves energy resources. Moreover, at the point of the transformer 1, from the Ampere loop law, the product of the magnetic field strength along the magnetic circuit and the average length of the magnetic circuit is equal to the product of the magnetomotive force, i.e. the excitation current and the number of turns of the excitation coil. From this, the magnetic field strength in the loop coil can be reduced, i.e. the formula H=NI/L, where H is the magnetic field strength, N is the number of turns of the secondary current wire 14, I is the excitation current and , L is the average length of the magnetic circuit. Equation demonstrates that L can be shortened to increase the high magnetic field strength in the coil under the condition of unaltered NI. The average magnetic path length L of the magnetic core 12 of the transformer 1 is closely related to the inner diameter and the outer diameter of the magnetic core 12 . In the transformer 1 having the same rated performance indicators, the primary current wire 2 and the wiring terminal 3 can reduce the inner diameter and the outer diameter of the magnetic core 12 after reducing the contact resistance, whereby reducing the average length of the magnetic circuit of the magnetic core 12 , reducing the volume of the transformer 1 , reducing the material of the magnetic core 12 of the transformer 1 , and reducing the length of the secondary coil of the transformer 1 . and reduce the internal coil of the transformer (1). In this way, the performance of the transformer 1 is improved, and the manufacturing cost of the transformer 1 can also be reduced.

After many experiments, the ideal hardness value of the primary current wire 2 is 70±10 Vickers. In this arrangement, when the outside of the connection hole 321 of the wiring terminal 3 is mechanically pressed, the snap teeth 323 can be easily embedded into the primary current wire 2 to achieve the most ideal fit and Optimized contact resistance is achieved.

Specifically, since the primary current wire 2 needs to use low-resistance materials, none of the existing low-resistance materials meet the aforementioned hardness requirements. Among them, the specific resistance of copper is 0.018 Ω·mm ² /m, but the hardness is as high as 120±10 Vickers. In the present invention, the primary current wire 2 is annealed using copper as a raw material, and its hardness is maintained at 70±10 Vickers through processing. In this way, both the low resistance requirement and the hardness requirement are met, so that the primary current wire 2 achieves or approaches a zero resistance contact with the wiring terminal 3 .

In other preferred embodiments of the present invention, brass, aluminum, or an aluminum alloy may also be selected as the raw material to be annealed to maintain its hardness at 70±10 Vickers.

Cooperating with the primary current wire 2, the hardness of the snap teeth 323 may be 140 to 170 Vickers. That is, the hardness of the material used for the snap teeth 323 is 140 to 170 Vickers. In this way, after the snap teeth 323 are pressed by an external machine, the snap teeth 323 can be easily embedded into the primary current wire 2, and the snap teeth 323 themselves are deformed due to mechanical pressing. it won't be

Preferably, the wiring terminal 3 may be made of H55-H68 brass material, so that the hardness of the snap tooth 323 may be 140 to 170 Vickers. In some embodiments, the hardness of the snap teeth 323 may be individually set to 140 Vickers to 170 Vickers, which does not coincide with the hardness of other portions of the wiring terminal 3 . Alternatively, the overall hardness of the wiring terminal 3 may be set to 140 Vickers to 170 Vickers. These are within the protection scope of the invention.

In the embodiment shown in the figures, the snap teeth 323 are helical threads. For example, during machining, the snap teeth 323 may be manufactured in the shape of a thread extending along the fore-and-aft direction. In this way, the threads are easy to machine and shape and are evenly distributed so that the snap teeth 323 can be evenly and firmly engaged with the primary current wire 2 after being pressed by an external machine. Of course, in other embodiments of the present invention, other shapes and/or arrangements of snap teeth 323 may also be used, as long as they are convex and can be embedded in the primary current wire 2 .

In a preferred embodiment, the primary current wire 2 has a curved cylindrical shape. Therefore, the cylindrical primary current wire 2 has better manufacturing and low resistance transmission performance compared with other primary current wires having other cross-sectional shapes.

The primary current wire 2 has two ends. Each of the two ends is inserted into the wiring terminal 3 . Accordingly, an optimum contact resistance can be achieved between the primary current wire 2 and the wiring terminal 3 .

Reference is made to Figs. 1 to 2 which are schematic diagrams of the structure of the wiring terminal 3 . The wiring terminal 3 is provided with a wiring fastening screw hole 316 in communication with the wiring hole 315 in the radial direction. The wiring hole 315 is used for insertion of an external power input/output wire. The wire fastening screw hole 316 is used for screwing and fixing external power input/output wires. In this way, the external power input/output wire can be stably electrically connected to the wiring terminal 3 . The wiring terminal 3 is radially provided with a fixing screw hole 317 for fixing with the meter housing 41 . In this embodiment, the fixing screw hole 317 is fixed to the wiring terminal box 4 . In this way, the connection structure between the transformer 1 and the wiring terminal 3 can be stably maintained on the meter housing 41 . In this embodiment, the meter housing 41 is specifically a wiring terminal box. The connection hole 321 and the wiring hole 315 face each other and do not communicate with each other. In this way, it is technically possible to prevent the outside air of the meter from entering the interior of the meter, corroding the internal components of the meter, and prolonging the service life of the meter.

The wiring terminal 3 is provided with a main body 31 and a columnar body 32 located at the front end of the main body 31 . The connecting hole 321 is recessed rearwardly from the front end of the columnar body 32 . The outer side of the columnar body 32 becomes polygonal after being pressed by an external machine. In this arrangement, after the columnar body 32 is pressed in multiple directions, the connecting hole 321 can be contracted inward more uniformly. It is worth noting that polygons can be regular polygons or irregular polygons. Of course, in other embodiments of the present invention, it may also be circular or any other regular or irregular shape.

In different embodiments of the invention, the transformer 1 may be a current transformer, a voltage transformer or a power sensor, as long as the current on the primary current wire 2 can be measured.

As shown in FIG. 7 , the present invention also protects a meter 40 , in particular an electrical energy meter, which comprises a frame-shaped meter housing 41 . The meter housing 41 includes a metering device 42 for converting and measuring the detection data transmitted by the secondary current wire 14 , a metering display device 43 for displaying electricity consumption data to a user, and a transformer 1 ) and a connection structure 100 of the wiring terminal 3 are provided.

Through specific experiments, the diameter of the primary current wire 2 is Φ3.5 to 6.0 mm, the diameter of the connection hole 321 is M4.0 to 7.0 mm, and the depth of the connection hole 321 is 10.0 to 8.0 mm , and when the outer diameter of the columnar body 32 is Φ7.0 to 12.5 mm, the contact resistance between the wiring terminal 3 and the primary current wire 2 is ideal, and the contact resistance is 0 to 5 uΩ.

The experimental data are as follows:

First embodiment: the diameter of the primary current wire 2 is Φ3.5 mm, the thread diameter of the connection hole 321 is M4.0 mm, the depth of the connection hole 321 is 10.0 mm, the columnar body ( When the outer diameter of 32) is ?7.0 to 8.5 mm, the contact resistance between the wiring terminal 3 and the primary current wire 2 is 0 to 5 u?.

Second embodiment: the diameter of the primary current wire 2 is Φ5.0 mm, the thread diameter of the connection hole 321 is M6.0 mm, the depth of the connection hole 321 is 9.0 mm, the columnar body ( When the outer diameter of 32) is ?8.5 to 10.0 mm, the contact resistance between the wiring terminal 3 and the primary current wire 2 is 0 to 5 u?.

Third embodiment: the diameter of the primary current wire 2 is Φ6.0 mm, the thread diameter of the connection hole 321 is M7.0 mm, the depth of the connection hole 321 is 8.0 mm, the columnar body ( When the outer diameter of 32) is ?10.5 to 12.5 mm, the contact resistance between the wiring terminal 3 and the primary current wire 2 is 0 to 5 u?.

Since this product is a power equipment that needs to be mass-produced and applied, it has very high requirements on its own power transmission stability and environmental adaptability.

First, during use, if a large current input occurs or an ultra-long current input occurs, it is easy to cause a high temperature in the connection structure between the transformer and the wiring terminal. The safety and stability of the connection structure of the transformer and the wiring terminal under high-temperature conditions are related to the metering accuracy of the electric energy meter, and if it is serious, it is related to the safety of the residents' use of electricity.

Second, the power equipment installation environment of the present invention is related to cold and hot and tropical. In particular, in the northern cold zone, when the outdoor temperature is extremely low, the method of ensuring the operation stability and measurement accuracy of the detection equipment in a low-temperature environment are also factors to be considered in the present invention.

Third, the power equipment of the present invention may also be involved in a vibrating environment, and the present invention needs to meet stability and consistency in a vibrating environment.

Therefore, it is necessary to perform high temperature, low temperature, and vibration tests on the product of the present invention, and the test conditions are as follows:

1. High temperature test:

The product is placed in a high-temperature test box at a temperature of 140°C. After 2000 hours, there is no change in contact resistance detected at an ambient temperature of 25°C.

2. Low temperature test:

The product is placed in a low temperature test box at a temperature of -40°C. After 2000 hours, there is no change in contact resistance detected at an ambient temperature of 25°C.

3. Vibration test:

According to the IEC60068-2-6 standard, there is no change in contact resistance after 40 scan cycles.

Of course, in other different embodiments of the present invention, the diameter of the primary current wire 2 , the diameter of the connection hole 321 , the depth of the connection hole 321 , and the outer diameter of the columnar body 32 may also have other values. can be set to

Hereinafter, embodiments shown in the drawings will be described in detail with reference to the drawings.

Referring to FIG. 6 which is an exploded view of the internal structure of the transformer 1 according to an embodiment of the present invention. The transformer 1 comprises a cylindrical plastic case 11 with an intermediate hole 13 . The annular magnetic core 12 is contained in a plastic case 11 . An intermediate hole 13 is provided in the middle of the plastic case 11 and the magnetic core 12 to allow the primary current to pass therethrough. The annular magnetic core 12 is provided with an inner diameter and an outer diameter. A coil of secondary current wire 14 is wound on a magnetic core 12 . The secondary current wire 14 is used to electrically connect with the secondary current lead wire 15 . The transformer 1 isolates and senses the primary current wire 2 and then extracts the sensed data through the secondary current lead wire 15 . In this embodiment, the magnetic core 12 includes an annular magnetic core shell and an ultrafine crystal magnetic core 12 positioned within the magnetic core shell. The ultrafine crystal magnetic core 12 is made of an amorphous thin ribbon and heat treated after winding, and is used to replace the permalloy to manufacture the current transformer 1 . The ultrafine crystal magnetic core 12 exhibits a very fast solidification rate of a metal or alloy (eg, an iron-boron alloy melt solidifies at a cooling rate of up to 1 million degrees/sec). In this process, the atoms are frozen before they can be neatly arranged, forming a final arrangement of atoms similar to the chaotic state of a liquid, forming an amorphous alloy. Then, this kind of amorphous alloy is subjected to special crystallization annealing to form a crystalline material called an ultrafine crystalline alloy. Since the atoms of the amorphous alloy are disorderly arranged, there is no crystal anisotropy and the specific resistance is high, so it has high permeability and low loss. It can replace silicon steel, permalloy and ferrite with transformer cores, transformers, sensors, etc., which can greatly improve transformer efficiency, reduce volume, reduce weight, and reduce energy consumption. However, the cost of amorphous materials and amorphous transformers is higher. For example, the price of an amorphous transformer of the same specification is 1.5 times the price of an S9, and it will take users about 7 to 8 years to recoup the initial increase in investment through energy savings. Some states have announced tax relief policies for producers and users of amorphous transformers, but users' enthusiasm is still not high. Only when the price of amorphous transformers is 1.3 times the price of S9 (the price of amorphous iron cores is reduced to about 30 yuan/kg) and it takes about 3-4 years for users to recoup the initial incremental investment through the saved energy consumption , users will have a stronger passion. Thus, how to reconcile the relationship between producers of amorphous strips and cores, producers of transformers, and users of transformers is the secret to whether amorphous materials can be used in large quantities. However, current applications of amorphous materials are predominantly biased towards cases with special requirements. If the above problems can be well solved, the market size of amorphous materials and amorphous tearing tools will grow rapidly. Accordingly, in the present invention, the reduction of the contact resistance between the primary current wire 2 and the wiring terminal 3 allows the inner diameter and the outer diameter of the magnetic core 12 to be reduced, whereby the magnetic core 12 is reduce the average length of the magnetic circuit of , reduce the volume of the transformer 1 , and reduce the material of the magnetic core 12 of the transformer 1 . As a result, the manufacturing cost of the transformer 1 can be effectively reduced, and there is a substantial advance in the development of amorphous transformers. Of course, in other embodiments of the present invention, magnetic core 12 may also be made of materials other than amorphous.

3 , 4 and 5 , a primary current wire 2 is used to connect the two wiring terminals 3 in series, and a transformer 1 is sleeved thereon. In this embodiment, the two wiring terminals 3 are arranged side by side on the left and right sides, the primary current wire 2 is U-shaped, and both ends of the primary current wire 2 are connected to the wiring terminals 3 used to connect. In other embodiments, the primary current wire 2 may also be arranged in other shapes.

1 to 2 , the wiring terminal 3 includes a main body 31 and a columnar body 32 extending forwardly from the main body 31 . The body 31 has a front end surface 311 , a rear end surface 312 opposite the front end surface 311 , a flat plane 313 between the front end surface 311 and the rear end surface 312 , and It has an arc surface 314 . The body 31 extends forwardly from the front end surface 311 . The connecting hole 321 is recessed along the front-rear direction from the front end of the columnar body 32 . Snap teeth 323 are provided on the inner sidewall 322 of the connection hole 321 . In this embodiment, the snap teeth 323 are threaded and provided, for example, in a tapping manner. In other embodiments, it may be a distribution of different shapes and positions, as long as it has concave and convex teeth. In the rear end surface 312 of the body 31, a wiring hole 315 is recessed along the front-rear direction. The wiring hole 315 and the connection hole 321 do not communicate in the front-rear direction. The three threaded holes are arranged side by side on the plane 313 , wherein the two threaded holes on the rear side are wire fastening screw holes 316 and one threaded hole on the front side is a set screw hole 317 . )am. The wiring fastening screw holes 316 communicate with the wiring hole 315 along the vertical direction. The screws 5 are adapted to be installed in each wire fastening screw hole 316 . The screw 5 is passed through the wire fastening screw hole 316 to fasten an input/output wire (not shown) passing through the wire hole 315 . The fixing screw hole 317 is used to fix the screw 5 so that the wiring terminal 3 and the meter housing 4 are fixed. After the primary current wire 2 is inserted into the columnar body 32, it is compressed outward by a mechanical pressing device, so that the connecting hole 321 is pressed and deformed inward. As a result, the snap teeth 323 are embedded into the primary current wire 2 .

During the pressing process, when the snap teeth 323 most rapidly contact the primary current wire 2, each of the snap teeth 323 is engaged with the primary current wire 2 in the front-rear direction. When the snap teeth 323 are further embedded, since the material of the primary current wire 2 is limited by the front and rear positioning of the snap teeth 323, the material of the primary current wire 2 is radially It is more likely to be embedded within the gaps between 323 . The gaps of the snap teeth 323 are fully engaged to achieve a seamless contact. Compared with the member of the snap teeth 323, when the columnar body 32 is mechanically pressed and retracted, the primary current wire 2 extends in the front-rear direction because the primary current wire 2 is positioned without breaking. tends to As a result, the diameter of the primary current wire 2 inside the connection hole 321 is small, which affects the overall resistance of the product.

In other embodiments, the columnar body 32 is not limited to a cylindrical shape. Moreover, the shape of the columnar body 32 after being mechanically pressed is not limited, and may be a regular shape such as a polygon, a circle, or other irregular shapes.

The present invention also protects the method of manufacturing the above-mentioned connecting structure of the transformer and the wiring terminal. The manufacturing method comprises the following steps:

A step A of manufacturing a wiring terminal and forming a connection hole on the wiring terminal and a snap tooth positioned in the connection hole;

Step B of manufacturing a primary current wire, and annealing the primary current wire to make the hardness of the snap teeth greater than that of the primary current wire;

It is worth noting that steps A and B can be performed before and after, simultaneously or alternately.

Step C, inserting the primary current wire into the connection hole of the wiring terminal, so that the snap teeth are arranged on the outside of the primary current wire; and

Step D. The snap teeth of the connection hole are embedded with the primary current wire to achieve zero resistance contact or perform external mechanical manipulation to press the wiring terminal to approximate this contact D.

In this arrangement, when an external mechanical pressure presses the connecting hole to contract, the snap tooth with greater hardness on the inner sidewall of the connecting hole can be easily embedded into the primary current wire with smaller hardness, between the two achieves near-complete close contact and seamless contact. On the other hand, the complete embedding of snap teeth can further increase the contact area between the primary current wire and the connecting hole in the radial direction. On the other hand, the axial restriction of the snap teeth can effectively prevent the primary current wire from being pressed to extend along the axial direction. In this way, the contact resistance of the connection between the primary current wire and the wiring terminal can be reduced, and the contact resistance is almost zero. This is the best choice for ensuring the stability of the working state of the connection structure, which reduces power consumption and saves energy resources. At the same time, the manufacturing cost of the transformer can be reduced, and the consistency of the connection is improved, making it stable and reliable.

Moreover, in the method of manufacturing the connecting structure of the transformer and the wiring terminal, the wiring terminal and the primary current wire can preferably be made of the above-mentioned materials, shapes, and hardness. Of course, in other embodiments of the present invention, the wiring terminal and the primary current wire may also be made of other materials, shapes and hardness.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art for the present invention. The terminology used in the description of the present invention is for the purpose of describing particular embodiments only, and is not intended to limit the present invention. As used herein, the term “or/and” includes any and all combinations of one or more related listed items.

Various technical features of the above-described embodiments may be arbitrarily combined for those skilled in the art. In order to simplify the description, not all possible combinations of the various technical features in the above-described embodiments are described. However, unless there is a contradiction in the combination of these technical features, it should be regarded as the scope of the present specification.

Although the foregoing embodiments represent only a few embodiments of the present invention, and the descriptions are more specific and detailed, they should not be construed as limiting the scope of the present invention. It should be pointed out that several modifications and improvements can be made for those skilled in the art without departing from the concept of the present invention, all of which fall within the protection scope of the present invention. Accordingly, the protection scope of the present invention shall be subject to the appended claims.

Claims (24)

A connection structure of a transformer and a wiring terminal, wherein the connection structure includes the transformer, a primary current wire and the wiring terminal;
One axial end of the wiring terminal is provided with a connection hole for connection with the primary current wire, and the other axial end of the wiring terminal is provided with a wiring hole for external electrical connection, the connection hole of the wiring terminal snap teeth are provided on the inner sidewall of the;
the transformer is sheathed on the primary current wire;
the primary current wire is inserted into the connecting hole, the hardness of the snap teeth is greater than that of the primary current wire, and the snap teeth are inserted into the primary current wire after the connecting hole of the wiring terminal is pressed by an external machine The connection structure of the transformer and wiring terminals, which is completely embedded in the zero ohmic contact to achieve or close to zero ohmic contact. The connecting structure of a transformer and a wiring terminal according to claim 1, wherein the hardness of the primary current wire is 70±10 Vickers. The connecting structure of a transformer and a wiring terminal according to claim 1, wherein the primary current wire is annealed using copper as a raw material, and the copper is annealed to a hardness of 70±10 Vickers. The connecting structure of a transformer and a wiring terminal according to claim 1, wherein the primary current wire is annealed using brass as a raw material, and the brass is annealed to a hardness of 70±10 Vickers. The connecting structure of a transformer and a wiring terminal according to claim 1, wherein the primary current wire is annealed using aluminum or an aluminum alloy as a raw material, and the aluminum or the aluminum alloy is annealed to a hardness of 70±10 Vickers. The connecting structure of a transformer and a wiring terminal according to claim 1, wherein the snap tooth has a hardness of 140 Vickers to 170 Vickers. The connecting structure of a transformer and a wiring terminal according to claim 1, wherein the hardness of the wiring terminal is 140 Vickers to 170 Vickers. The connecting structure of a transformer and a wiring terminal according to claim 1, wherein the wiring terminal is made of H55-H68 brass material.

2. The wiring terminal according to claim 1, wherein the wiring terminal is provided with a wiring fastening screw hole communicating with the wiring hole in a radial direction, the wiring hole being used for inserting an external power input/output wire, and the wiring fastening screw hole being the outer used for screwing and fixing the power input/output wire, wherein the wiring terminal is provided with a fixing screw hole for fixing with the meter housing in a radial direction, the connection hole and the wiring hole are opposite and do not communicate with each other; and Connection structure of wiring terminals. The connecting structure of claim 1, wherein the snap teeth are helical threads. 9. The columnar body according to claim 8, wherein the wiring terminal is provided with a main body and a columnar body located at the front end of the main body, the connecting hole is recessed rearwardly from the front end of the columnar body, and the outer surface of the columnar body is A connection structure of a transformer and a wiring terminal, which is contracted inward after being pressed by the external machine. The connecting structure of a transformer and a wiring terminal according to claim 10, wherein the outer surface of the columnar body becomes polygonal after being pressed by the external machine. 10. The connection structure of the transformer and wiring terminal according to claim 9, wherein the diameter of the primary current wire is Φ3.5 mm to Φ6.0 mm, and the diameter of the threads of the connection hole is M4.0 mm to M7.0 mm. . The connecting structure of a transformer and a wiring terminal according to claim 10, wherein an outer diameter of the columnar body is ?7.0 mm to ?12.5 mm. The connecting structure of a transformer and a wiring terminal according to claim 1, wherein a depth of the connecting hole is 10.0 mm to 8.0 mm. The connection structure of claim 1, wherein a contact resistance connecting the wiring terminal and the primary current wire is 0 uΩ to 5 uΩ. The connecting structure of a transformer and a wiring terminal according to claim 1, wherein the primary current wire has a curved cylindrical shape. The connecting structure of a transformer and a wiring terminal according to claim 1, wherein the primary current wire has two ends, and each of the two ends is inserted into the wiring terminal. The connecting structure of a transformer and a wiring terminal according to claim 1, wherein the transformer is a current transformer, a voltage transformer or a power sensor. As a meter,
A meter comprising a metering device, a metering display device, and a meter housing having a connection structure of a transformer and a wiring terminal according to any one of claims 1 to 18. A method for manufacturing a connection structure of a transformer and a wiring terminal according to any one of claims 1 to 18, comprising:
A step A of manufacturing the wiring terminal, and forming the connection hole on the wiring terminal and snap teeth positioned in the connection hole;
B manufacturing the primary current wire, annealing the primary current wire to make the hardness of the snap tooth greater than that of the primary current wire;
a step C of inserting the primary current wire into the connection hole of the wiring terminal, so that the snap teeth are arranged outside the primary current wire; and
connection of a transformer and a wiring terminal, comprising the step D of performing an external mechanical operation for pressing the wiring terminal so that the snap teeth of the connection hole are embedded into the primary current wire to achieve or close to zero resistance contact How to manufacture the structure. The transformer according to claim 20, wherein the wiring terminal is formed of a columnar body, the connecting hole is formed by recessing from the columnar body, and the snap teeth in the connecting hole are made in a thread shape extending along the front-rear direction. and a method of manufacturing the connection structure of the wiring terminal. The method according to claim 21, wherein the diameter of the primary current wire is Φ3.5 mm, the diameter of the threads of the connection hole is M4.0 mm, the depth of the connection hole is 10.0 mm, and the outer diameter of the columnar body is A method for manufacturing a connection structure of a transformer and a wiring terminal, wherein the contact resistance is 0 uΩ to 5 uΩ, wherein the contact resistance connecting the wiring terminal and the primary current wire is φ7.0 mm to φ8.5 mm. The method according to claim 21, wherein the diameter of the primary current wire is Φ5.0 mm, the diameter of the threads of the connection hole is M6.0 mm, the depth of the connection hole is 9.0 mm, and the outer diameter of the columnar body is Φ8.5 mm to Φ10.0 mm, and a contact resistance connecting the wiring terminal and the primary current wire is 0 uΩ to 5 uΩ. 22. The method according to claim 21, wherein the diameter of the primary current wire is Φ6.0 mm, the diameter of the threads of the connection hole is M7.0 mm, the depth of the connection hole is 8.0 mm, and the outer diameter of the columnar body is ?10.5 mm to ?12.5 mm, and a contact resistance connecting the wiring terminal and the primary current wire is 0 uΩ to 5 uΩ.

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