Current sensor based on open-loop principle

Abstract

The utility model provides a current sensor based on the open-loop principle, including PCB, insert body and cover plate, the upper surface of insert body is equipped with fixed through-hole and fixed groove that pass through the upper and lower surface of insert body, fixed current row in fixed through-hole, fixed 4pin connector on one side surface of insert body, fixed 4pin connector on one side surface of insert body, fixed 4pin connector on the other side surface of insert body, fixed 4pin connector on the other side surface of insert body. A fixing groove is formed in the insert body, a pin on the 4pin connector protrudes out of the insert body and is located in the fixing groove, the current bar, the 4pin connector and the insert body are integrally formed in an injection molding mode, the cover plate and the PCB are sequentially installed in the fixing groove from top to bottom, the PCB is fixed through the cover plate above the PCB, and when the PCB is placed in the fixing groove, the PCB is connected with the pin of the 4pin connector. The other side face, opposite to the side face where the 4pin connector is fixed, of the insert body is provided with a side face groove, the side face groove penetrates through the current bar, the magnetic core is fixed in the side face groove, the production process of the open-loop current sensor is optimized, the open-loop current sensor is more convenient to assemble, and the tool cost is effectively saved.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, which is applied to industrial fields such as photovoltaics and energy storage, and is specifically a current sensor based on an open-loop principle. Background Art

[0002] A current sensor is a detection device that can sense the information of the measured current and convert the sensed information into an electrical signal or other required form of information output that meets certain standards according to certain rules to meet the requirements of information transmission, processing, storage, display, recording and control.

[0003] Current sensors are also called magnetic sensors. They can be used in household appliances, smart grids, electric vehicles, wind power generation, etc. There are many magnetic sensors used in our lives, such as computer hard drives, compasses, household appliances, etc.

[0004] The Hall current sensor is based on the magnetic balance Hall principle. According to the Hall effect principle, a current Ic is passed from the control current end of the Hall element, and a magnetic field with a magnetic induction intensity of B is applied in the normal direction of the Hall element plane. Then, an electric potential VH will be generated perpendicular to the current and magnetic field direction (i.e., between the Hall output ends). It is called the Hall potential, and its magnitude is proportional to the product of the control current I and the magnetic induction intensity B. That is, there is a formula: K is the Hall coefficient, which is determined by the material of the Hall element; I is the control current; B is the magnetic induction intensity; VH is the Hall potential.

[0005] like Figure 1 As shown, 1. current bus; 2. magnetic core; 3. housing; 4. PCB; 5. 4-pin connector. The existing series of open-loop Hall current sensors have the following structural design disadvantages:

[0006] 1. The assembly between the current bus, pins and housing is relatively complicated;

[0007] 2. When welding connectors, welding tools need to be made, which increases costs;

[0008] 3. The current strip shakes after assembly;

[0009] 4. Glue is required for core assembly. Utility Model Content

[0010] In order to solve the above technical problems, the utility model proposes a current sensor based on the open-loop principle, which optimizes the production process of the open-loop current sensor, makes its assembly more convenient, and effectively saves tooling costs.

[0011] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0012] A current sensor based on the open-loop principle, characterized in that it includes a PCB, an insert body and a cover plate, the upper surface of the insert body is provided with a fixing through hole and a fixing groove that penetrates the upper and lower surfaces and one side of the insert body, a current row is fixed in the fixing through hole, a 4-pin connector is fixed on one side surface of the insert body, the pins on the 4-pin connector protrude from the insert body and are located in the fixing groove, the current row, the 4-pin connector and the insert body are integrally injection molded, the PCB and the cover plate have the same shape as the fixing groove, the cover plate and the PCB are fixed in the fixing groove from top to bottom in sequence, when the PCB is placed in the fixing groove, the PCB and the pins of the 4-pin connector are welded and fixed, when the PCB is fixed in the fixing groove, the cover plate is clamped and fixed with the inner wall of the fixing groove, and is located above the PCB and the pins of the 4-pin connector, and also includes a magnetic core, a side groove is provided on the other side of the insert body opposite to the fixed 4-pin connector, the side groove passes through the current row, and the magnetic core is fixed in the side groove.

[0013] In the above structure: the current sensor based on the open-loop principle proposed in the present application includes a PCB, an insert body and a cover plate. The insert body, the current bar and the 4-pin connector are directly injection-molded as one piece, which optimizes the subsequent pressing and assembly processes, and can easily solve the problem of the current bar shaking during the subsequent pressing. The PCB and the cover plate have the same shape as the fixed groove. The cover plate and the PCB are installed in the fixed groove from top to bottom in sequence. When the PCB is placed in the fixed groove, the PCB and the pins of the 4-pin connector are welded and fixed. After the PCB is fixed in the fixed groove, the cover plate is clamped and fixed to the inner wall of the fixed groove, and is located above the pins of the PCB and the 4-pin connector, so as to protect the PCB and the 4-pin connector pins. By directly injection-molding the pins of the 4-pin connector with the insert body, the PCB is directly pasted into the fixed groove for welding during welding, which eliminates the need for welding tooling and saves costs.

[0014] The invention also includes a magnetic core, and a side groove for installing the magnetic core is opened on the other side of the insert body opposite to the side where the 4-pin connector is fixed, and the side groove passes through the current row.

[0015] Further: slide plates are respectively provided on the sides of the cover plate, and slide grooves are respectively provided on the sides of the inner walls of the fixing groove. After the PCB is fixed in the fixing groove, glue is dispensed on the slide plates and then inserted into the slide grooves on the inner walls of the fixing groove. At this time, there is a gap of 0.1 mm between the side surfaces of the cover plate and the side walls of the fixing groove.

[0016] In the above structure: two steps with different wall thicknesses are arranged on both sides of the cover plate to form a slide plate, and grooves are made on both sides of the corresponding positions on the inner wall of the fixed groove to form a slide groove, leaving a gap of 0.1mm on one side. During assembly, glue is applied to the slide plates on both sides of the cover plate and then inserted into the fixed groove to complete the assembly, thereby fixing the cover plate.

[0017] Furthermore: two limiting ribs are arranged on the inner wall of the side groove. When the magnetic core is inserted into the side groove, there is a gap of 0.mm between the magnetic core and the inner wall of the side groove. The limiting ribs form an interference fit structure between the magnetic core and the inner wall of the side groove.

[0018] Furthermore: an elastic buckle is also provided on the inner wall of the side groove, and the elastic buckle is close to the opening of the side groove. When the magnetic core is inserted into the side groove, the front end surface of the magnetic core presses against the bottom wall of the side groove, and the rear end surface abuts against the elastic buckle, thereby limiting the magnetic core.

[0019] In the above structure: two limiting ribs are arranged on the inner wall of the side groove, and a 0.1mm interference fit structure is formed between the magnetic core and the inner wall of the side groove through the limiting ribs. In addition, an elastic buckle is also arranged on the inner wall of the side groove, and the elastic buckle is close to the opening of the side groove. When the magnetic core is inserted into the side groove, the front end surface of the magnetic core presses against the bottom wall of the side groove, and the rear end surface presses against the elastic buckle, thereby limiting the magnetic core, ensuring that the magnetic core and the plastic shell are tightly fitted without shaking, and no glue is required.

[0020] Furthermore: the current busbar is made of red copper, and the red copper is T2 red copper.

[0021] In the above structure: the current busbar is made of copper. Since the product has requirements for the primary current, copper has a higher current carrying capacity than brass and is relatively soft and easy to bend, so we gave up the brass material and used copper T2 instead.

[0022] Furthermore: the insert body is made of plastic material, and the plastic material is PA66+GF30 plastic material.

[0023] In the above structure: because the working temperature of the product is -40℃-125℃, and the magnetic core needs to be fixed, it not only has requirements for high temperature resistance, but also has certain requirements for the strength of the insert body. Therefore, the PA66+GF30 material that meets the requirements is selected. The PA66+GF30 plastic material has the advantages of strong environmental resilience, high mechanical strength, better antistatic performance, high temperature resistance and more stable size.

[0024] Compared with the prior art, the beneficial effects of the utility model are:

[0025] This application optimizes the production process of the open-loop current sensor, making its assembly more convenient and effectively saving tooling costs. The insert body in this application is made of plastic material, and the plastic material is PA66+GF30 plastic material. Therefore, this application has the advantages of strong environmental resilience, high mechanical strength, better antistatic performance, high temperature resistance, and more stable size. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of an open-loop Hall current sensor in the prior art;

[0027] Figure 2 It is a schematic diagram of the structure of the current sensor in this application;

[0028] Figure 3 is a side view of the core end on the insert body in the present application;

[0029] Figure 4 It is a cross-sectional view of the side of the insert body in this application.

[0030] List of reference numerals:

[0031] 1. Magnetic core; 2. PCB; 3. Insert body; 4. Cover plate; 5. Current bus; 6. 4-pin connector; 7. Fixing groove; 8. Slide plate; 9. Slide groove; 10. Interference fit structure; 11. Elastic buckle. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods:

[0033] like Figure 1-4As shown, the utility model proposes a current sensor based on the open-loop principle, including a PCB2, an insert body 3 and a cover plate 4, wherein the upper surface of the insert body 3 is provided with a fixing through hole and a fixing groove 7 penetrating the upper and lower surfaces and one side of the insert body 3, a current row 5 is fixed in the fixing through hole, a 4-pin connector 6 is fixed on one side of the insert body 3, the pins on the 4-pin connector 6 protrude from the insert body 3 and are located in the fixing groove 7, the current row 5, the 4-pin connector 6 and the insert body 3 are integrally formed by injection molding, and the PCB2 and the cover plate 4 are connected to the fixing groove 7. The shapes are the same, and the cover plate 4 and PCB2 are fixed in the fixing groove 7 from top to bottom in sequence. When the PCB2 is placed in the fixing groove 7, the PCB2 and the pins of the 4-pin connector 6 are welded and fixed. After the PCB2 is fixed in the fixing groove 7, the cover plate 4 is clamped and fixed with the inner wall of the fixing groove 7, and is located above the pins of the PCB2 and the 4-pin connector 6. It also includes a magnetic core 1, and a side groove is opened on the other side of the insert body 3 opposite to the 4-pin connector 6. The side groove is set through the current row 5, and the magnetic core 1 is fixed in the side groove.

[0034] The present application proposes a current sensor based on the open-loop principle, including a PCB2, an insert body 3 and a cover plate 4. The insert body 3, the current row 5 and the 4-pin connector 6 are directly injection-molded as one piece, which optimizes the subsequent pressing and assembly processes, and can easily solve the problem of the current row 5 shaking when pressed in at the later stage. The PCB2 and the cover plate 4 have the same shape as the fixing groove 7. The cover plate 4 and the PCB2 are sequentially installed in the fixing groove 7 from top to bottom. When the PCB2 is placed in the fixing groove 7, the pins of the PCB2 and the 4-pin connector 6 are welded and fixed. After the PCB2 is fixed in the fixing groove 7, the cover plate 4 is clamped and fixed to the inner wall of the fixing groove 7, and is located above the pins of the PCB2 and the 4-pin connector 6, so as to protect the pins of the PCB2 and the 4-pin connector 6. By directly injection-molding the pins of the 4-pin connector 6 with the insert body 3, the PCB2 is directly pasted into the fixing groove 7 for welding during welding, thereby eliminating welding tooling and saving costs.

[0035] The invention also includes a magnetic core 1 , and a side groove for mounting the magnetic core 1 is provided on the other side of the insert body 3 opposite to the side where the 4-pin connector 6 is fixed, and the side groove passes through the current row 5 .

[0036] In this embodiment: slide plates 8 are respectively provided on the side surfaces of the cover plate 4, and slide grooves 9 are respectively provided on the side surfaces of the inner walls of the fixing groove 7. After the PCB 2 is fixed in the fixing groove 7, the slide plates 8 are glued and then inserted into the slide grooves 9 on the inner walls of the fixing groove 7. At this time, there is a gap of 0.1 mm between the side surfaces of the cover plate 4 and the side walls of the fixing groove 7.

[0037] Two steps with different wall thicknesses are arranged on both sides of the cover plate 4 to form a slide plate 8, and grooves are made on both sides of the corresponding positions on the inner wall of the fixing groove 7 to form a slide groove 9, leaving a gap of 0.1 mm on one side. During assembly, glue is applied to the slide plates 8 on both sides of the cover plate 4 and then inserted into the fixing groove 7 to complete the assembly, thereby fixing the cover plate 4.

[0038] In this embodiment: two limiting ribs are arranged on the inner wall of the side groove. When the magnetic core 1 is inserted into the side groove, there is a gap of 0.mm between the magnetic core 1 and the inner wall of the side groove. The limiting ribs form an interference fit structure 10 between the magnetic core 1 and the inner wall of the side groove.

[0039] In this embodiment: an elastic buckle 11 is also provided on the inner wall of the side groove, and the elastic buckle 11 is close to the opening of the side groove. When the magnetic core 1 is inserted into the side groove, the front end surface of the magnetic core 1 presses against the bottom wall of the side groove, and the rear end surface abuts against the elastic buckle 11, thereby limiting the magnetic core 1.

[0040] Two limiting ribs are arranged on the inner wall of the side groove, and a 0.1mm interference fit structure 10 is formed between the magnetic core 1 and the inner wall of the side groove through the limiting ribs. In addition, an elastic buckle 11 is also arranged on the inner wall of the side groove. The elastic buckle 11 is close to the opening of the side groove. When the magnetic core 1 is inserted into the side groove, the front end surface of the magnetic core 1 presses against the bottom wall of the side groove, and the rear end surface presses against the elastic buckle 11, so as to limit the magnetic core 1, ensure that the magnetic core 1 and the plastic shell are tightly fitted without shaking, and no glue is required.

[0041] In this embodiment: the current bar 5 is made of copper, and copper is T2 copper. The current bar 5 is made of copper. Since the product has requirements for the primary current, copper has a higher current carrying capacity than brass, and is relatively soft and easy to bend, so we gave up the brass material and used copper T2 instead.

[0042] In this embodiment: the insert body 3 is made of plastic material, and the plastic material is PA66+GF30. Because the working temperature of the product is -40℃-125℃, and the magnetic core 1 needs to be fixed, it not only has requirements for high temperature resistance, but also has certain requirements for the strength of the insert body 3. Therefore, PA66+GF30 material that meets the requirements is selected. PA66+GF30 plastic material has the advantages of strong environmental adaptability, high mechanical strength, better antistatic performance, high temperature resistance and more stable size.

[0043] The present application optimizes the production process of the open-loop current sensor, makes its assembly more convenient, and effectively saves tooling costs. The insert body 3 in the present application is made of plastic material, and the plastic material is selected from PA66+GF30 plastic material, so the present application has the advantages of strong environmental resilience, high mechanical strength, better antistatic performance, high temperature resistance, and more stable size.

[0044] The above is only a preferred embodiment of the present invention and does not constitute any other limitation on the present invention. Any modification or equivalent change made based on the technical essence of the present invention still falls within the scope of protection required by the present invention.

Claims

1. A current sensor based on the open loop principle, characterized in that: The invention comprises a PCB (2), an insert body (3) and a cover plate (4); a fixing through hole and a fixing groove (7) penetrating the upper and lower surfaces and one side of the insert body (3) are provided on the upper surface of the insert body (3); a current bus (5) is fixed in the fixing through hole; a 4-pin connector (6) is fixed on one side of the insert body (3); the pins on the 4-pin connector (6) protrude from the insert body (3) and are located in the fixing groove (7); the current bus (5), the 4-pin connector (6) and the insert body (3) are integrally formed by injection molding; the PCB (2) and the cover plate (4) have the same shape as the fixing groove (7); the cover plate (4) and The PCB (2) is fixed in the fixing groove (7) from top to bottom. When the PCB (2) is placed in the fixing groove (7), the PCB (2) and the pins of the 4-pin connector (6) are fixed by welding. After the PCB (2) is fixed in the fixing groove (7), the cover plate (4) is fixed by snapping with the inner wall of the fixing groove (7) and is located above the pins of the PCB (2) and the 4-pin connector (6). It also includes a magnetic core (1). A side groove is provided on the other side of the insert body (3) opposite to the side where the 4-pin connector (6) is fixed. The side groove passes through the current row (5). The magnetic core (1) is fixed in the side groove.

2. A current sensor based on the open-loop principle according to claim 1, characterized in that: The side surfaces of the cover plate (4) are respectively provided with slide plates (8), and the side surfaces of the inner walls of the fixing groove (7) are respectively provided with slide grooves (9). When the PCB (2) is fixed in the fixing groove (7), the slide plates (8) are glued and then inserted into the slide grooves (9) on the inner walls of the fixing groove (7). At this time, a gap of 0.1 mm is provided between the side surfaces of the cover plate (4) and the side walls of the fixing groove (7).

3. The current sensor based on the open-loop principle according to claim 1, characterized in that: Two limiting ribs are arranged on the inner wall of the side groove. When the magnetic core (1) is inserted into the side groove, there is a gap of 0.mm between the magnetic core (1) and the inner wall of the side groove. The limiting ribs form an interference fit structure (10) between the magnetic core (1) and the inner wall of the side groove.

4. The current sensor based on the open loop principle according to claim 1, characterized in that: An elastic buckle (11) is also provided on the inner wall of the side groove, and the elastic buckle (11) is close to the opening of the side groove. When the magnetic core (1) is inserted into the side groove, the front end surface of the magnetic core (1) presses against the bottom wall of the side groove, and the rear end surface abuts against the elastic buckle (11), thereby limiting the position of the magnetic core (1).

5. The current sensor based on the open loop principle according to claim 1, characterized in that: The current busbar (5) is made of red copper, and the red copper is selected from T2 red copper.

6. The current sensor based on the open-loop principle according to claim 1, characterized in that: The insert body (3) is made of plastic material, and the plastic material is PA66+GF30 plastic material.

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