CN115625844A

CN115625844A - Processing technology of integrally-formed current sensor

Info

Publication number: CN115625844A
Application number: CN202211277341.4A
Authority: CN
Inventors: 曾嵘; 吕阳; 叶明盛; 黄文斌; 吴明明; 孙炎
Original assignee: Ningbo CRRC Times Transducer Technology Co Ltd
Current assignee: Ningbo CRRC Times Transducer Technology Co Ltd
Priority date: 2022-10-19
Filing date: 2022-10-19
Publication date: 2023-01-20

Abstract

The invention provides a processing technology of an integrated forming current sensor, belonging to the technical field of sensors and comprising the following steps: s1: assembling the sensor internal modules, and putting the assembled sensor internal modules into an injection mold; s2: drying the hot melt adhesive; s3: melting the hot melt adhesive; s4: carrying out heat preservation treatment on the hot melt adhesive in a molten state; s5: closing the mold and maintaining the pressure after glue injection; s6: opening the die and completing the demoulding of the product; s7: baking and annealing the demoulded product; s8: and (5) laser marking, and packaging the product. The invention realizes the preparation of the integrally formed current sensor through the hot melt adhesive.

Description

Processing technology of integrally-formed current sensor

Technical Field

The invention belongs to the technical field of sensors, and relates to a processing technology of an integrated forming current sensor.

Background

With the promotion of a cost reduction and efficiency improvement strategy in the domestic manufacturing industry, the traditional design idea of the current sensor is difficult to meet the requirements of cost reduction and efficiency improvement. The traditional current sensor is based on different principles, and the internal structure of the product has certain difference, but basically comprises an internal PCBA, an induction device, an external shell, pouring sealant and the like. The product formed by the structure has mature technical design scheme, stable process route and good consistency.

Because the existing sensors are provided with the external shells, when the whole sensor is assembled, the basic assembly process is based on the external shells, then other components of the sensor are installed in the external shells one by one, and then glue pouring and packaging are carried out, so that the following problems exist, firstly, the assembly process is complex, and if misassembly or neglected assembly occurs, the assembly needs to be carried out again, and the consumed time is long; secondly, the bus bar is a part used for transmitting electricity in the sensor parts, is generally arranged in a U-shaped structure, and can be bent twice to complete installation when being installed in the shell; thirdly, the encapsulating package easily produces internal stress, thereby affecting the precision of the sensor, and in addition, causing the condition of package cracking.

Disclosure of Invention

The invention aims to solve the problems in the prior art and provides a processing technology for realizing the integrated molding of a current sensor.

The purpose of the invention can be realized by the following technical scheme: a processing technology of an integrated forming current sensor comprises the following steps:

s1: assembling the sensor internal modules, and putting the assembled sensor internal modules into an injection mold;

s2: drying the hot melt adhesive to remove water in the hot melt adhesive, wherein the drying temperature is 70 ℃, and the heating time is 4-8hrs;

s3: melting the hot melt adhesive, and keeping the hot melt adhesive in a molten state again, wherein the melting temperature of the hot melt adhesive is 210-240 ℃;

s4: carrying out heat preservation treatment on the hot melt adhesive in a molten state, wherein the temperature of the hot melt adhesive is maintained at 210-240 ℃ and the temperature of an injection mold is maintained at 20-60 ℃ in the heat preservation state;

s5: closing the mold and maintaining the pressure after glue injection, wherein the injection pressure during glue injection is 0.5MPa, the pressure maintaining pressure is 5.5MPa, and the pressure maintaining time is 5s, so that the hot melt adhesive can quickly fill the whole mold cavity during pressure maintaining;

s6: opening the mold and demolding the product, wherein the hot melt adhesive is cooled and solidified after filling the mold cavity, and the cooling and solidifying time is 40S;

s7: baking and annealing the demolded product, wherein the temperature during baking and annealing is maintained between 55 and 65 ℃;

s8: and (5) laser marking, and packaging the product.

In the above processing technology of the integrated forming current sensor, the injection mold comprises a carrier, and the assembled sensor internal module is loaded into the carrier, wherein the step S1 comprises the steps of:

s11: inserting a contact pin in the sensor internal module into the first positioning hole, and inserting the bus bar into the second positioning hole, wherein when a coil framework of the sensor internal module is provided with a positioning column, the positioning column is inserted into the third positioning hole, and when a positioning bulge is arranged on the cavity bottom of the carrier, a circuit board assembly in the sensor internal module is in abutting fit with the positioning bulge;

s12: the installation of the sliding block on the carrier is completed through the insertion fit between the positioning convex column at the bottom of the cavity and the positioning concave hole in the upper sliding block of the carrier, and the internal module of the sensor is clamped between the two sliding blocks;

s13: and sliding the carrier loaded with the sensor inner module into the lower die cavity to complete the loading of the carrier on the die.

In the above processing process of the integrally molded current sensor, the step S5 includes the steps of:

s51: during die assembly, the positioning column on the upper die plate of the injection mold is used for pressing the sliding block, and the first inclined plane on the positioning block on the upper die plate is in sliding fit with the second inclined plane on the carrier, so that the degree of freedom of the carrier in a die cavity is limited.

In the above process for integrally forming the current sensor, the step S6 includes the steps of:

s61: when the mold is opened, the abutting between the positioning column and the sliding block and the sliding between the first inclined plane and the second inclined plane are released, and the carrier is integrally taken down from the mold cavity;

s62: taking the two sliding blocks down from the carrier;

s63: and removing the packaged sensor from the carrier.

In the processing technology of the integrated forming current sensor, the cavity bottom of the cavity is provided with a boss.

In the processing technology of the integrated forming current sensor, the upper die cavity of the upper die plate is internally provided with two convex blocks, and the two convex blocks are oppositely arranged.

In the processing technology of the integrated forming current sensor, a first exhaust channel communicated with an upper mold cavity is arranged on an upper mold plate, a second exhaust channel communicated with the mold cavity is arranged on a carrier, a first exhaust insert is embedded in the first exhaust channel, a second exhaust insert is embedded in the second exhaust channel, when a mold is closed, the first exhaust insert and the second exhaust insert are abutted and matched, and exhaust is carried out through a gap between contact surfaces of the first exhaust insert and the second exhaust insert.

In the processing technology of the integrated molding current sensor, the lower template of the injection mold is provided with a glue inlet channel, the glue inlet channel is at least provided with two branches, one branch is used as a channel for glue to flow to the upper mold cavity and the lower mold cavity, and the rest branches are used as buffer channels for slowing down the flow rate of the glue.

In foretell integrated into one piece current sensor's processing technology, the inside module of sensor is including gathering the magnetic assembly, and should gather the magnetic assembly and include first iron core, second iron core and third iron core, and first iron core, the structure of second iron core is the same, the third iron core is strip setting, wherein, first iron core is including the first core section that is C type setting, and the both sides length of first core section open end differs, wherein, bend along keeping away from the longer one end of length along the shorter one end edge of length in the first core section open end and form the second core section that is the L type, and the opening direction mutually perpendicular of the opening direction of first core section and second core section.

In the above processing technology of the integrally formed current sensor, the first iron core and the second iron core are connected to the third iron core side by side, and the opening direction of the first core segment in the first iron core is opposite to the opening direction of the first core segment in the second iron core, wherein the longer end of the first core segment in the first iron core is overlapped with the longer end of the first core segment in the second iron core, the opening direction of the second core segment in the first iron core is opposite to the opening direction of the second core segment in the second iron core, and the first and second support arms are communicated with each other, wherein the second support arm in the support penetrates through the second core segment of the first iron core and the second core segment of the second iron core.

Compared with the prior art, the invention has the following beneficial effects:

(1) The utility model relates to a low modulus, the hot melt adhesive of low coefficient of expansion encapsulates inside module of sensor, on the one hand can reduce the stress of material, guarantee that whole encapsulation system adapts to ambient temperature and changes, can solve the sensor under the environment of temperature variation, take place the problem of encapsulation fracture, and the problem of internal stress to the influence of sensor precision, on the other hand hot melt adhesive through after the cooling has replaced original shell structure, can effectively reduce the whole volume of sensor, the process that adopts shell structure still to carry out the encapsulating encapsulation after the sensor assembly is accomplished has been reduced, the sensor modularization has been satisfied, the demand of miniaturization, in addition, because the shell structure of original female sensor of arranging has been lacked, make the installation of female row need not to realize the assembly through twice bending, with this assembly efficiency who improves the sensor, improve the uniformity of product simultaneously.

(2) The inner module of the sensor after the assembly can be placed in a die, the inner module of the sensor can be accurately positioned in the die through the contact pins and the busbar, then hot melt adhesive in a molten state is injected into the die, and after the hot melt adhesive is cooled, a layer of shell structure covered by the hot melt adhesive can be formed on the surface of the inner module of the sensor, so that the shell structure is greatly improved in insulation and pressure resistance.

(3) Through setting up the elastic component, can compensate the mould because the error that the assembly brought guarantees that the locating lever can carry out the butt cooperation with the slider all the time after the mould compound die to this improves the fashioned reliability of sensor integration encapsulation, and then guarantees the precision of sensor when follow-up use.

(4) The utility model discloses a sensor, including the sensor, the sensor is provided with the sensor, through set up the boss on the die cavity bottom of the chamber, make from advancing the colloid that injects in the gluey passageway and can't fill this position, make on the fashioned sensor of encapsulation and the corresponding position of boss form interior concave surface, and the existence of this interior concave surface, area of contact when sensor after can reducing the encapsulation links to each other with other structures, thereby reduce the plane degree requirement of sensor installation face, fully guarantee the sensor can the level of installation, reduce the risk that the sensor atress is uneven to bring because of the installation when the sensor uses.

(5) The convex block is arranged in the upper die cavity, so that the part cannot be filled by the colloid injected from the glue inlet channel, and the part corresponding to the convex block on the sensor formed by packaging forms a concave part. And through the setting of concave part, realize the homogenization of the inside module outside hot melt adhesive thickness of whole sensor, and then further reduce the stress that arouses because of the encapsulation to this precision that improves the sensor and use.

(6) Through the cooperation between first exhaust mold insert, the second exhaust mold insert, as mould exhaust use when moulding plastics, reduce the risk such as the stranded gas of moulding plastics and the filling of moulding plastics is incomplete.

(7) Through setting up buffering passageway, can further reduce the colloid and flow rate when flowing into die cavity, lower die cavity to further reduce the colloid to the impact of sensor inner module, reduce the influence of injection pressure to the sensor performance, and then improve the precision in the use behind the sensor package shaping.

Drawings

Fig. 1 is a schematic structural diagram of a mold in the machining process of the integrally molded current sensor.

FIG. 2 is a schematic view of the injection mold of FIG. 1 with the upper mold assembly removed.

Fig. 3 is a schematic structural diagram of a carrier according to a preferred embodiment of the present invention.

Fig. 4 is a partial structural schematic view of the carrier shown in fig. 3.

FIG. 5 is a schematic structural diagram of a slider according to a preferred embodiment of the present invention.

FIG. 6 is a schematic structural diagram of an upper mold assembly in accordance with a preferred embodiment of the present invention.

Fig. 7 is an enlarged view of a portion a in fig. 6.

FIG. 8 is a schematic view of the upper die assembly of FIG. 6 from another perspective.

Fig. 9 isbase:Sub>A sectional view ofbase:Sub>A-base:Sub>A in fig. 8.

Fig. 10 is a sectional view of B-B in fig. 8.

FIG. 11 is a schematic structural diagram of an upper mold plate according to a preferred embodiment of the present invention.

Fig. 12 is an enlarged view of portion B in fig. 11.

Fig. 13 is a schematic structural diagram of a packaged product in the process of manufacturing an integrally molded current sensor according to the present invention.

FIG. 14 is a schematic diagram of the internal module of the sensor according to a preferred embodiment of the present invention.

Fig. 15 is a schematic structural view of a circuit board assembly and a supporting assembly according to a preferred embodiment of the invention.

Fig. 16 is a schematic view of the circuit board assembly and support assembly of fig. 15 from another perspective.

FIG. 17 is a schematic structural diagram of a support assembly and a magnetic gathering assembly according to a preferred embodiment of the invention.

Fig. 18 is a schematic structural diagram of a first core according to a preferred embodiment of the invention.

In the figure, 100, a sensor internal module; 110. a circuit board assembly; 111. a PCB board; 112. inserting a pin; 113. a connecting plate; 114. positioning a plate; 120. a support assembly; 121. a support; 1211. a first support arm; 1212. a second support arm; 122. a bracket connection member; 130. a magnetic gathering component; 131. a first iron core; 1311. a first core segment; 1312. a second core segment; 132. a second iron core; 133. a third iron core; 140. a first coil component; 141. a first coil bobbin; 142. a first coil; 143. a first frame connecting member; 150. a second coil assembly; 151. a second coil bobbin; 152. a second coil; 153. a second frame connecting member; 154. a positioning column; 160. a busbar;

200. a mold; 210. an upper die assembly; 211. feeding a mold frame; 212. mounting a template; 2121. an upper mold cavity; 2122. a first exhaust passage; 2123. a bump; 213. a thimble; 214. positioning a rod; 215. an elastic member; 216. positioning a block; 2161. a first inclined plane; 217. a first exhaust insert; 220. a lower die assembly; 221. a lower die frame; 222. a lower template; 2221. a lower die cavity; 2222. a glue inlet channel; 2223. a buffer channel; 230. a carrier; 231. a cavity; 2311. a first positioning hole; 2312. a second positioning hole; 2313. positioning the projection; 2314. positioning the convex column; 2315. a boss; 232. a second exhaust passage; 233. a slider; 2331. positioning concave holes; 234. a second inclined plane; 235. a second venting insert.

Detailed Description

The following are specific embodiments of the present invention and are further described with reference to the drawings, but the present invention is not limited to these embodiments.

It should be noted that all directional indicators (such as up, down, left, right, front, back \8230;) in the embodiments of the present invention are only used to explain the relative positional relationship between the components, the motion situation, etc. in a specific posture (as shown in the attached drawings), and if the specific posture is changed, the directional indicator is changed accordingly.

As shown in fig. 1 to 18, the processing technology of the integrally molded current sensor provided by the invention comprises the following steps:

s1: assembling the sensor internal module 100, and placing the assembled sensor internal module 100 into an injection mold 200;

s2: drying the hot melt adhesive; drying the hot melt adhesive before injection molding to remove water in the hot melt adhesive, wherein the drying temperature is 70 ℃, and the heating time is 4-8hrs;

s3: melting the hot melt adhesive; adding the dried hot melt adhesive into an injection molding machine for melting treatment, wherein the melting temperature of the hot melt adhesive is 210-240 ℃;

s4: carrying out heat preservation treatment on the hot melt adhesive in a molten state, wherein the temperature of the hot melt adhesive is maintained at 210-240 ℃, and the temperature of the die 200 is maintained at 20-60 ℃;

s5: closing the mold and completing glue injection and pressure maintaining; the carrier 230 is loaded into the mold 200, and then the mold assembly of the mold 200 is completed, at this time, the hot melt adhesive is injected into the mold cavity of the mold 200 under a certain pressure, wherein the injection molding pressure is 0.5MPa, and the pressure is maintained for a preset time, and the pressure maintaining pressure is 5.5MPa, and the pressure maintaining time is 5s. During the pressure maintaining period, the hot melt adhesive can quickly fill the whole die cavity;

s6: opening the die and completing the demoulding of the product; namely, the hot melt adhesive is cooled and solidified after filling the die cavity, wherein the cooling time is 40s, after 40s, the die 200 is opened, the sensor after injection molding together with the carrier 230 is taken down from the die 200, then the sensor after injection molding is taken down from the carrier 230, and if the sensor is difficult to demould, a proper amount of demoulding agent can be sprayed on the surface of the sensor;

s7: baking and annealing; the sensor after injection molding is baked and annealed at the temperature of 55-65 ℃ to release residual stress, so that the influence of the temperature residual stress on the sensor is further reduced;

s8: laser marking and packaging the product; that is, logo and product information of a corresponding company are seal-cut on the die 200, and only product change needs to be marked during laser marking, so that the marking time is shortened to 20% of the original marking time, and the processing time and the processing cost of the product are further reduced.

It should be noted that the sensor internal module 100 in the present embodiment includes:

the circuit board assembly 110 comprises a PCB 111 and a contact pin 112 electrically connected with the PCB 111, wherein when the hot melt adhesive is coated on the outer side of the sensor inner module 100, a part of the contact pin 112 electrically connected with the PCB 111 is located in the hot melt adhesive, a part of the contact pin 112 away from the PCB 111 is located outside the hot melt adhesive, and the circuit board assembly 110 is vertically arranged;

the supporting component 120 is horizontally arranged, the supporting component 120 includes a bracket 121, and one end of the bracket 121 is electrically connected to the PCB 111 near one end of the contact pin 112 through a bracket connecting member 122;

the magnetism gathering assembly 130 is connected to the other end of the bracket 121 and forms a nested fit with the bracket 121 at the end, wherein two connecting areas which are distributed up and down are arranged on the magnetism gathering assembly 130 and are respectively a first connecting area and a second connecting area;

a first coil assembly 140 including a first coil bobbin 141 forming a nested fit with the first connection region, and a first coil 142 wound on the first coil bobbin 141, wherein one end of the first coil bobbin 141 is electrically connected to the PCB 111 through a first bobbin connector 143;

a second coil assembly 150 including a second coil bobbin 151 in a nested fit with the second connection region, and a second coil 152 wound around the second coil bobbin 151, wherein one end of the second coil bobbin 151 is electrically connected to the PCB 111 through a second bobbin connector 153;

many female arranging 160 is independent setting, and female arranging 160 is the setting of U type, wherein, female closed end centre gripping of arranging 160 is between first coil subassembly 140 and second coil subassembly 150, female opening direction towards second coil subassembly 150 of arranging 160, when the hot melt adhesive cladding is in the outside of the inside module 100 of sensor, female closed end of arranging 160 is located the hot melt adhesive, and the both sides of female arranging 160 open end are located outside the hot melt adhesive.

In this embodiment, encapsulate sensor inner module 100 through a low modulus, low coefficient of expansion's hot melt adhesive, on the one hand, can reduce the stress of material, guarantee that whole encapsulation system adapts to ambient temperature and changes, can solve the sensor under temperature variation's environment, take place the problem of encapsulation fracture, and the problem of internal stress to sensor precision influence, on the other hand has replaced original shell structure through the hot melt adhesive after the cooling, can effectively reduce the whole volume of sensor, the process that adopts shell structure still to carry out the encapsulating after the sensor assembly is accomplished has been reduced, sensor modularization has been satisfied, miniaturized demand, in addition, owing to lack the shell structure of original sensor, make the installation of female arranging 160 need not to realize the assembly through twice bending, with this assembly efficiency who improves the sensor, improve the uniformity of product simultaneously.

In addition, the assembled sensor internal module 100 can be placed in the mold 200, and the precise positioning of the sensor internal module 100 in the mold 200 is realized through the contact pins 112 and the bus bars 160, and then the hot melt adhesive in a molten state is injected into the mold 200, after the hot melt adhesive is cooled, a layer of "outer shell structure" covered by the hot melt adhesive can be formed on the surface of the sensor internal module 100, and the insulation and pressure resistance of the "outer shell structure" is greatly improved.

And the hot melt adhesive is injection type dimer acid type polyamide hot melt resin with low modulus (50-200 MPa) and low thermal expansion coefficient (200-300 ppmk). The hot melt resin has good cold flexibility and high extensibility, and shows good weather resistance under severe temperature impact conditions.

It should be noted that the injection mold 200 in this embodiment includes:

the upper die assembly 210 comprises an upper die frame 211, an upper die plate 212 connected with the upper die frame 211 through a fastener, and an upper die cavity 2121 and a first exhaust channel 2122 communicated with the upper die cavity 2121 are arranged on the upper die plate 212;

the lower die assembly 220 comprises a lower die frame 221, a lower die plate 222 connected with the lower die frame 221 through a fastener, and a lower die cavity 2221 and a glue inlet channel 2222 communicated with the upper die cavity 2121 and the lower die cavity 2221 are arranged on the lower die plate 222;

the carrier 230 is detachably connected with the lower mold cavity 2221, a cavity 231 for placing the sensor inner module 100 is arranged in the carrier 230, and a slider 233 for clamping the sensor inner module 100 placed in the cavity 231 and a second exhaust channel 232 communicated with the cavity 231 are arranged on two sides of the cavity 231.

Preferably, when the sensor inner module 100 is integrally packaged on the injection mold 200, the sensor inner module 100 is placed in the carrier 230, and the carrier 230 and the lower mold cavity 2221 form a detachable connection, so that when the sensor inner module 100 is integrally packaged, not only the sensor inner module 100 but also the carrier 230 need to be positioned, thereby ensuring the accuracy of the packaged sensor.

Further preferably, in order to realize the positioning of the sensor internal module 100 in the carrier 230, a first positioning structure is provided, and the first positioning structure is located between the cavity bottom of the cavity 231 and the sensor internal module 100, wherein a first positioning hole 2311, a second positioning hole 2312 and a third positioning hole are provided on the cavity bottom of the cavity 231, the first positioning hole 2311 is in insertion fit with the pin 112, the second positioning hole 2312 is in insertion fit with the busbar 160, and the third positioning hole is in insertion fit with the positioning column 154 on the second coil frame 151.

It should be noted that the first positioning structure may be disposed between the upper mold plate 212 and the sensor inner module 100, instead of between the bottom of the cavity 231 and the sensor inner module 100. When the first positioning structure is disposed between the upper mold plate 212 and the sensor inner module 100, the first positioning structure includes the ejector pins 213 disposed on the upper mold plate 212, and the positioning protrusions 2313 disposed at the bottom of the cavity 231, wherein the upper and lower ends of the circuit board assembly 110 are respectively in abutting engagement with the ejector pins 213 and the positioning protrusions 2313, and the sensor inner module 100 can be reliably positioned in the cavity 231.

Therefore, for the precise positioning of the sensor internal module 100 in the carrier 230, there may be two ways, one of which is to realize the positioning of the sensor internal module 100 in the carrier 230 through the insertion and connection between the first positioning hole 2311 and the insertion pin 112, between the second positioning hole 2312 and the bus bar 160, and between the third positioning hole and the positioning post 154; secondly, the positioning of the sensor internal module 100 in the carrier 230 is realized through the insertion and engagement between the first positioning hole 2311 and the pin 112, the insertion and engagement between the second positioning hole 2312 and the busbar 160, and the abutting and engagement between the circuit board assembly 110, the thimble 213 and the positioning protrusion 2313.

It should be noted that, since the sensor module is also clamped by the sliders 233 at both sides when the sensor module is installed in the cavity 231, the sliders 233 in the cavity 231 need to be positioned. Therefore, a second positioning structure is provided for positioning the slider 233, and the second positioning structure is located between the bottom of the cavity 231 and the slider 233, wherein the bottom of the cavity 231 is provided with a positioning protrusion 2314, and the slider 233 is provided with a positioning concave hole 2331.

The slider 233 is generally made of metal, and therefore, the positioning protrusion 2314 is made of magnetic material, so that when the slider 233 is connected to the carrier 230, the slider 233 can be restricted in the degree of freedom in the cavity 231 in the horizontal direction through the insertion and connection between the positioning protrusion 2314 and the positioning concave hole 2331, and can be restricted in the degree of freedom in the vertical direction of the slider 233 in the cavity 231 through the magnetic attraction and connection between the positioning protrusion 2314 and the slider 233. The magnetic attraction matching is adopted, so that the slider 233 can be conveniently detached from the carrier 230 after the sensor is integrally packaged and molded, and the sensor can be conveniently taken down from the cavity 231.

Further preferably, since the second positioning structure can only achieve the limitation of the degree of freedom of the sliding block 233 in the horizontal direction, and cannot achieve the limitation of the degree of freedom of the sliding block 233 in the vertical direction, a third positioning structure is provided between the upper die plate 212 and the sliding block 233, and the third positioning structure includes a positioning rod 214 provided on the upper die plate 212, and an elastic member 215 is nested on the positioning rod 214, wherein the elastic member 215 is clamped between the upper die plate 212 and the positioning rod 214.

It should be noted that when the upper mold plate 212 and the lower mold plate 222 are closed, the positioning rod 214 and the slider 233 are in abutting engagement, and the slider 233 is firmly pressed against the bottom of the cavity 231, thereby limiting the degree of freedom of the slider 233 and the carrier 230 in the vertical direction. In addition, by arranging the elastic piece 215, errors caused by assembly of the mold 200 can be compensated, and the positioning rod 214 can be always abutted and matched with the sliding block 233 after the mold 200 is closed, so that the reliability of integrated packaging and forming of the sensor is improved, and the accuracy of the sensor in subsequent use is ensured.

Further preferably, by providing the third positioning structure, not only the limitation of the degree of freedom of the slider 233 in the vertical direction but also the limitation of the degree of freedom of the carrier 230 in the vertical direction can be achieved, but the degree of freedom of the carrier 230 in the horizontal direction is not limited. Therefore, there is a fourth positioning structure between the upper mold plate 212 and the carrier 230, and the fourth positioning structure includes a positioning block 216 disposed on the upper mold plate 212, and a first inclined surface 2161 is disposed on the positioning block 216, and a second inclined surface 234 disposed on the carrier 230 and contacting with the first inclined surface 2161, wherein when the mold 200 is closed, the first inclined surface 2161 slides on the surface of the second inclined surface 234, so that the carrier 230 is pressed into the lower mold cavity 2221 without moving horizontally.

It should be noted that the fourth positioning structure realizes the wedge-shaped fit between the upper template 212 and the carrier 230, so as to realize the definition of the degree of freedom of the carrier 230 in the horizontal direction. Moreover, since the fourth positioning structure is disposed between the upper mold plate 212 and the carrier 230, when the mold is opened, the upper mold plate 212 moves away from the lower mold plate 222, and the wedge-shaped fit between the upper mold plate 212 and the carrier 230 is released, so that the carrier 230 can be conveniently detached from the lower mold plate 222 without affecting the demolding of the carrier 230.

Preferably, a boss 2315 is provided on the bottom of the cavity 231, and the lower surface of the sensor inner block 100 is in contact with the boss 2315 when the sensor inner block 100 is fitted into the cavity 231.

In this embodiment, through set up boss 2315 at the bottom of the die cavity 231 cavity, make the colloid of pouring into from advancing in gluey passageway 2222 can't fill this position, make the position corresponding with boss 2315 on the fashioned sensor of encapsulation form the interior concave surface, and the existence of this interior concave surface, area of contact when sensor after can reducing the encapsulation links to each other with other structures, thereby reduce the flatness requirement of sensor installation face, fully guarantee the sensor can the level of installation, reduce the risk that the sensor atress is uneven and brings because of the installation is uneven when the sensor uses.

Preferably, two protrusions 2123 are disposed in the upper cavity 2121, and the two protrusions 2123 are disposed oppositely, wherein two recesses are formed at corresponding positions of the sensor after the sensor is integrally packaged.

It should be noted that, by providing the bump 2123 in the upper cavity 2121, the colloid injected from the colloid inlet channel 2222 cannot fill the portion, so that a concave portion is formed on the encapsulated sensor at the portion corresponding to the bump 2123. And through the arrangement of the concave part, the homogenization of the thickness of the hot melt adhesive outside the whole sensor inner module 100 is realized, and further the stress caused by packaging is further reduced, so that the use precision of the sensor is improved.

Preferably, when the mold 200 is closed, the first exhaust passage 2122 is communicated with the second exhaust passage 232 to form an exhaust passage of the mold 200, wherein the first exhaust insert 217 is embedded in the first exhaust passage 2122, the second exhaust passage 235 is embedded in the second exhaust passage 232, and when the mold 200 is closed, the first exhaust insert 217 is abutted and matched with the second exhaust insert 235, and exhaust is performed through a gap between contact surfaces of the first exhaust insert 217 and the second exhaust insert 235.

It should be noted that the first exhaust insert 217 and the second exhaust insert 235 are matched to exhaust the mold 200 during injection, so as to reduce the risks of injection trapping, incomplete injection filling and the like.

Preferably, the glue inlet channel 2222 is provided with at least two branches, wherein one branch serves as a channel for glue to flow to the upper mold cavity 2121 and the lower mold cavity 2221, and the remaining branch serves as a buffer channel 2223 for slowing down the flow rate of the glue.

In this embodiment, when the colloid flows in from advancing gluey passageway 2222, certain impact force has, the inside module 100 of sensor who places in die cavity 231 has realized the location through a plurality of location structures, and through setting up buffer passage, can further reduce the colloid and flow rate when flowing into last die cavity 2121, lower die cavity 2221 to further reduce the colloid to the impact of inside module 100 of sensor, reduce the influence of injection pressure to the sensor performance, and then improve the precision in the use behind the sensor package shaping.

Preferably, the circuit board assembly 110 further includes a connecting plate 113, and the pin 112 penetrates the connecting plate 113, wherein a slot for inserting and positioning the pin 112 is provided on the PCB 111, and a clamping fit is formed between the connecting plate 113 and the PCB 111, wherein the clamping position is located on two sides of the PCB 111 or the connecting plate 113.

Further preferably, a positioning plate 114 is disposed on one side of the connecting plate 113 facing the second coil frame 151, and the positioning plate 114 is U-shaped, wherein a closed end of the positioning plate 114 is attached to the PCB 111, and an open end of the positioning plate 114 is inserted into the second coil frame 151.

Preferably, the stand 121 is disposed in a T shape, and the stand 121 includes a first arm 1211 and a second arm 1212, wherein the number of the stand connecting members 122 is two, and the two stand connecting members are respectively connected to two ends of the first arm 1211, and the second arm 1212 serves as a connecting position of the iron core.

Preferably, the magnetic gathering component 130 includes a first core 131, a second core 132, and a third core 133, and the first core 131 and the second core 132 have the same structure, and the third core 133 is disposed in a strip shape, wherein the first core 131 includes a first core segment 1311 disposed in a C shape, and the lengths of two sides of an opening end of the first core segment 1311 are different, wherein an edge of an end of the first core segment 1311 with a shorter length is bent along an end of the first core segment 1311 with a longer length away from the end of the first core segment 1311 to form a second core segment 1312 with an L shape, and an opening direction of the first core segment 1311 is perpendicular to an opening direction of the second core segment 1312.

It should be mentioned that the first core 131 and the second core 132 are connected to the third core 133 side by side, and an opening direction of the first core segment 1311 in the first core 131 is opposite to an opening direction of the first core segment 1311 in the second core 132, wherein a longer end of the first core segment 1311 in the first core 131 and a longer end of the first core segment 1311 in the second core 132 are stacked up and down, an opening direction of the second core segment 1312 in the first core 131 is opposite to an opening direction of the second core segment 1312 in the second core 132, and are communicated with each other, wherein the second arm 1212 in the bracket 121 passes through the second core segment 1312 of the first core 131 and the second core segment 1312 of the second core 132.

In addition, the end of the first core segment 1311 of the first core 131 having a longer length and the end of the first core segment 1311 of the second core 132 having a longer length constitute a first connection region; the end of the first core segment 1311 of the first core 131 having a shorter length, the second core segment 1312 of the first core 131, the end of the first core segment 1311 of the second core 132 having a shorter length, the second core segment 1312 of the second core 132, and the third core 133 constitute a second connection region.

Preferably, the first coil bobbin 141 and the second coil bobbin 151 are both arranged in an i-shaped structure.

Claims

1. The machining process of the integrally formed current sensor is characterized by comprising the following steps of:

s5: closing the die and maintaining the pressure after glue injection is completed, wherein the injection pressure during glue injection is 0.5MPa, the pressure maintaining pressure is 5.5MPa, and the pressure maintaining time is 5s, so that the hot melt adhesive can quickly fill the whole die cavity during pressure maintaining;

s8: and (5) laser marking, and packaging the product.

2. The machining process of the integrally formed current sensor according to claim 1, wherein the injection mold comprises a carrier, and the assembled sensor internal modules are loaded into the carrier, wherein the step S1 comprises the steps of:

s12: the installation of the slide block on the carrier is completed through the insertion fit between the positioning convex column at the cavity bottom of the cavity and the positioning concave hole in the upper slide block of the carrier, and the internal module of the sensor is clamped between the two slide blocks;

s13: and sliding the carrier loaded with the sensor inner module into the lower mold cavity to complete the loading of the carrier on the mold.

3. The process for manufacturing an integrally molded current sensor according to claim 2, wherein the step S5 comprises the steps of:

4. The process for manufacturing an integrally molded current sensor according to claim 3, wherein the step S6 comprises the steps of:

s62: taking the two sliding blocks down from the carrier;

s63: and removing the packaged sensor from the carrier.

5. The process for manufacturing an integrally molded current sensor according to claim 2, wherein a boss is provided on the cavity bottom of the cavity.

6. The process for manufacturing an integrally formed current sensor as claimed in claim 3, wherein the upper cavity of the upper mold plate has two protrusions disposed therein, and the two protrusions are disposed opposite to each other.

7. The process for manufacturing the integrally formed current sensor according to claim 3, wherein the upper mold plate is provided with a first exhaust channel communicated with the upper mold cavity, and the carrier is provided with a second exhaust channel communicated with the mold cavity, wherein a first exhaust insert is embedded in the first exhaust channel, a second exhaust insert is embedded in the second exhaust channel, and when the mold is closed, the first exhaust insert and the second exhaust insert are in abutting fit, and exhaust is performed through a gap between contact surfaces of the first exhaust insert and the second exhaust insert.

8. The processing technology of the integrally formed current sensor as claimed in claim 1, wherein the lower template of the injection mold is provided with a glue inlet channel, and the glue inlet channel is provided with at least two branches, wherein one branch is used as a channel for glue to flow to the upper mold cavity and the lower mold cavity, and the remaining branches are used as buffer channels for slowing down the flow rate of the glue.

9. The processing technology of the integrally formed current sensor according to claim 1, wherein the sensor internal module comprises a magnetism gathering assembly, the magnetism gathering assembly comprises a first iron core, a second iron core and a third iron core, the first iron core and the second iron core are identical in structure, the third iron core is arranged in a strip shape, the first iron core comprises a first core section which is arranged in a C shape, the lengths of two sides of an opening end of the first core section are different, the second core section which is arranged in an L shape is formed by bending an edge of one end, which is shorter in length, of the opening end of the first core section along the end, which is far away from the end, which is longer in length, of the opening end of the first core section, and the opening direction of the first core section is perpendicular to the opening direction of the second core section.

10. The processing technology of the integrally formed current sensor according to claim 9, wherein the first iron core and the second iron core are connected to the third iron core side by side, and the opening direction of the first core segment in the first iron core is opposite to the opening direction of the first core segment in the second iron core, wherein the end with longer length of the first core segment in the first iron core and the end with longer length of the first core segment in the second iron core are stacked up and down, the opening direction of the second core segment in the first iron core is opposite to the opening direction of the second core segment in the second iron core and are communicated with each other, and the second arm in the bracket passes through the second core segment of the first iron core and the second core segment of the second iron core.