CN222201442U - Mould - Google Patents

Abstract

The application relates to a die, and belongs to the technical field of industrial molding equipment. The mold comprises a first mold unit, a second mold unit and a positioning needle, wherein the first mold unit comprises a first molding surface, a plurality of first movable holes are formed in the first molding surface, the second mold unit comprises a second molding surface, a plurality of first movable holes are formed in the second molding surface, the positioning needle is in sliding fit with the inner wall of the first movable holes, a molding cavity for injection molding is formed by the first molding surface and the second molding surface, an insert is placed inside the molding cavity, and one end of the positioning needle is abutted to the insert. The mold provided by the embodiment of the application can position the insert, and reduce the risk of deformation and damage of the insert, the mold and the molded product.

Description

Mould

Technical Field

The application relates to the technical field of processing and forming equipment, in particular to a die.

Background

The mould is a variety of moulds and tools used for injection moulding, blow moulding, extrusion, die casting or forging, smelting, stamping and other methods in industrial production to obtain the required products. The insert in-mold injection molding is a molding process for producing a new part by placing external parts such as metal parts or molded plastic parts in a mold before molding and wrapping all or part of plastic outside the original part by an injection molding machine. The mold corresponding to the process is an insert in-mold injection mold. At present, the in-mold injection molding of inserts has wider application, and particularly, electronic elements bearing strong current are required to be subjected to in-mold injection molding. The insert injection mold has the advantages that the subsequent installation process is completed in the molding process, so that the subsequent assembly process is saved, and the connection tightness between parts is improved more importantly. However, when the injection mold is developed, the insert needs to be accurately positioned in the mold, when the insert is not well matched with the mold, the insert is easy to crush the mold, flash is easy to occur on a molded plastic product, and deformation of the plastic product or deformation of the insert is easy to occur.

Disclosure of utility model

The present application aims to solve the above problems, and an object of the present application is to provide a mold capable of positioning an insert, reducing the risk of deformation and damage of the insert, the mold, and a molded article, and improving the above problems.

The application provides a mold which is used for in-mold injection of an insert, and comprises a first mold unit, a second mold unit and a positioning needle, wherein the first mold unit comprises a first molding surface, the first molding surface is provided with a plurality of first movable holes, the second mold unit comprises a second molding surface, the second molding surface is provided with a plurality of first movable holes, the positioning needle is in sliding fit with the inner wall of the first movable holes, the first molding surface and the second molding surface enclose a molding cavity for injection, the insert is placed inside the molding cavity, and one end of the positioning needle is abutted against the insert.

In the technical scheme of the embodiment of the application, in the use process of the die provided by the embodiment of the application, the insert is placed and hung in the forming cavity, the first forming surface and the second forming surface are respectively positioned at two opposite sides of the insert, the first forming surface is provided with a plurality of first movable holes, the second forming surface is provided with a plurality of first movable holes, positioning needles are arranged in the first movable holes and are in sliding fit with the inner walls of the first movable holes, the positioning needles slide along the movable holes to be abutted against the insert, the positioning needles arranged in the first movable holes of the first forming surface and the positioning needles arranged in the first movable holes of the second forming surface are abutted against the insert from two sides in the vertical direction, so that the displacement of the insert in the forming cavity is limited, the risk of scratch or collision between the insert and the first die unit or the second die unit is reduced, and the risk of deformation or damage of the insert, the die and a formed product caused by the displacement of the insert is reduced.

In some embodiments, the first movable bore includes a first bore section and a second bore section, the first bore section being smaller in bore diameter than the second bore Duan Kaojin than the forming cavity, a step surface being formed between the first bore section and the second bore section, the positioning pin being provided with a protrusion disposed around the positioning pin, the protrusion being located within the second bore section and in contact with the step surface.

In the technical scheme of the embodiment of the application, the bulge is positioned in the second hole section, when the positioning needle is abutted against the insert, the bulge is contacted with the step surface, and the step surface limits the bulge to move towards the forming cavity so as to limit the upper limit of the force applied to the insert by the positioning piece, thereby reducing the risk of damage to the insert caused by excessive extrusion of the positioning needle.

In some embodiments, a pressing plate is arranged on one side, away from the forming cavity, of the first die unit and the second die unit, an elastic piece is sleeved on the positioning needle, and two ends of the elastic piece are respectively abutted to the protrusion and the pressing plate.

In the technical scheme of the embodiment of the application, the pressing plate can seal the opening of the second hole section extending to the surface of the first die unit (or the second die unit), two ends of the elastic piece are respectively abutted with the bulge and the pressing plate, the positioning needle can move towards the insert until being abutted with the insert under the pushing of the elastic force provided by the elastic piece, when the injection molding is nearly finished, the fluid in the forming cavity can apply the force opposite to the elastic force of the elastic piece to the positioning needle, when the force of the fluid in the forming cavity applied to the positioning needle is larger than the elastic force of the elastic piece, the elastic piece is compressed by the force of the fluid in the forming cavity applied to the positioning needle, the positioning needle moves along the first hole Duan Beili forming cavity under the pushing of the force of the fluid, and therefore the fluid can fill the inner space of the forming cavity occupied by the positioning needle, and the formed plastic material can completely wrap the part of the insert in the forming cavity.

In some embodiments, the pressing plate is provided with a plurality of second movable holes, the second movable holes are in one-to-one correspondence with the first movable holes, and one end of the positioning needle, which is away from the forming cavity, extends into the second movable holes.

According to the technical scheme, one end of the positioning needle, which deviates from the forming cavity, extends into the second movable hole, when the positioning needle is pushed by fluid in the forming cavity to deviate from the forming cavity to move, one end of the positioning needle, which deviates from the forming cavity, enters the second movable hole until the bulge contacts with the pressing plate, the pressing plate limits the positioning needle to move continuously, and when the positioning needle stops moving, one end of the positioning needle, which faces the forming cavity, can be flush with the first forming surface (or the second forming surface) so as to block the communication position of the first hole section and the forming cavity, and the risk of redundant flash of a formed product is reduced.

In some embodiments, on the positioning needle, with the protrusion as a separation, a portion of the positioning needle facing the molding cavity is a first needle segment, a portion of the positioning needle facing the platen is a second needle segment, the first needle segment is at least partially located within the first hole segment, and the second needle segment is at least partially located within the second movable hole.

In the technical scheme of the embodiment of the application, the second needle section is at least partially positioned in the second movable hole, and when the bulge is contacted with the step surface and the first needle section is abutted against the insert, the second needle section is at least partially positioned in the second movable hole, so that the risk that the second needle section is separated from the second movable hole is reduced, and the second needle section can be kept in the second movable hole in the process of moving the positioning needle back and forth.

In some embodiments, on the positioning needle, the diameter of the first needle section is larger than the diameter of the second needle section, and the inner wall of the second movable hole is in sliding fit with the second needle section.

According to the technical scheme, the inner wall of the second movable hole is in sliding fit with the second needle section, so that on one hand, the second movable hole limits the moving direction of the second needle section, the risk of the second needle section deviating from the vertical direction is reduced, and on the other hand, the second movable hole can be well plugged by the second needle section.

In some embodiments, a clamping groove is formed in one end, facing the forming cavity, of the positioning needle, and the clamping groove is matched with the insert.

According to the technical scheme, the extending directions of the clamping grooves of the positioning pins are parallel to the horizontal direction, the clamping grooves of the positioning pins clamp different parts of the insert respectively, the clamping grooves can limit the movement of the insert on the horizontal plane in the direction perpendicular to the clamping grooves, the extending directions of the clamping grooves of the positioning pins can be perpendicular to each other, and therefore the movement of the clamping grooves in the horizontal direction is limited, and the positioning effect on the insert is improved.

In some embodiments, the plurality of first movable holes of the first mold unit correspond to the plurality of first movable holes of the second mold unit.

In the technical scheme of the embodiment of the application, the positions of the first movable holes of the first die unit and the positions of the first movable holes of the second die unit are in one-to-one correspondence, any one of the first movable holes of the first die unit and the first movable holes of the second die unit corresponding to the positions of the first movable holes are in one group, and the force applied to the insert by the positioning needle in each group of the movable holes can be applied to the same area of the insert so as to offset each other, so that the risk that the insert is damaged due to shearing force caused by the offset of the positioning needle in the first movable hole of the first die unit and the force applied to the insert by the positioning needle in the first movable hole of the second die unit is reduced.

In some embodiments, the insert is further comprised, and a positioning groove for fixing the insert is arranged on the inner wall of the molding cavity, and the insert is used for mounting the insert.

In the technical scheme of the embodiment of the application, part of the end part of the metal insert in the electronic element needs to be exposed outside, and the part of the end part can be inserted into the insert, so that the insert is suspended in the forming cavity.

Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a mold according to some embodiments of the present application;

FIG. 2 is a top view of a mold provided in some embodiments of the application;

FIG. 3 is a cross-sectional view at A-A in FIG. 2;

FIG. 4 is an enlarged view at B in FIG. 3;

FIG. 5 is a schematic view of a first mold unit according to some embodiments of the present application;

FIG. 6 is a schematic view of a positioning pin and insert according to some embodiments of the present application;

Fig. 7 is a schematic structural view of a positioning needle according to some embodiments of the present application.

The icons are 1-insert, 10-molded article, 2-first mold unit, 20-first molding surface, 3-second mold unit, 30-second molding surface, 4-first movable hole, 40-first hole section, 41-second hole section, 42-step surface, 5-pilot pin, 50-protrusion, 51-elastic member, 52-first pin section, 53-second pin section, 54-neck, 6-molding cavity, 7-platen, 70-second movable hole, 8-insert.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

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 to which this application belongs, the terms used in the description of this application in this application are for the purpose of describing particular embodiments only and are not intended to be limiting of the application, and the terms "comprising" and "having" and any variations thereof in the description of this application and the claims and the above description of the drawings are intended to cover non-exclusive inclusions. The terms first, second and the like in the description and in the claims or in the above-described figures, are used for distinguishing between different objects and not necessarily for describing a particular sequential or chronological order.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the described embodiments of the application may be combined with other embodiments.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "attached" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, directly connected, indirectly connected through an intermediary, or may be in communication with the interior of two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

The term "and/or" in the present application is merely an association relation describing the association object, and indicates that three kinds of relations may exist, for example, a and/or B may indicate that a exists alone, while a and B exist together, and B exists alone. In the present application, the character "/" generally indicates that the front and rear related objects are an or relationship.

The term "plurality" as used herein means two or more (including two), and similarly, "plural sets" means two or more (including two), and "plural sheets" means two or more (including two).

According to some embodiments of the present application, as shown in fig. 1, 3 and 5-6, the present application provides a mold for in-mold injection molding of an insert 1, the mold includes a first mold unit 2, a second mold unit 3 and a positioning needle 5, the first mold unit 2 includes a first molding surface 20, the first molding surface 20 is provided with a plurality of first movable holes 4, the second mold unit 3 includes a second molding surface 30, the second molding surface 30 is provided with a plurality of first movable holes 4, the positioning needle 5 is in sliding fit with an inner wall of the first movable holes 4, wherein the first molding surface 20 and the second molding surface 30 enclose a molding cavity 6 for injection molding, the insert 1 is placed inside the molding cavity 6, and one end of the positioning needle 5 abuts against the insert 1.

The first mold unit 2 may be an upper mold (or a lower mold), and the second mold unit 3 may be a lower mold (or an upper mold).

The first mold unit 2 may be a female mold and the second mold unit 3 may be a female mold or a male mold, or the first mold unit 2 may be a male mold and the second mold unit 3 may be a female mold.

The number of the plurality of first movable holes 4 on the first molding surface 20 may be three, four, five, six, seven, eight, nine, ten or more.

The number of the plurality of first movable holes 4 on the second molding surface 30 may be three, four, five, six, seven, eight, nine, ten or more.

The number of the first movable holes 4 on the first molding surface 20 is equal to the number of the first movable holes 4 on the second molding surface 30.

The insert 1 according to the application may be, but is not limited to, a part of metal, plastic material.

The vertical direction referred to in the present application is the X direction in the figure. The first mold unit 2 and the second mold unit 3 are clamped in the vertical direction, and the positioning pin 5 and the first movable hole 4 also extend in the vertical direction.

The die provided by the embodiment of the application can be applied to the production process of various products such as daily necessities shells, insulating products, electronic elements and the like. The present application is described by taking an electronic component as an example.

In the use process of the die provided by the embodiment of the application, the insert 1 is placed and hung in the forming cavity 6, the first forming surface 20 and the second forming surface 30 are respectively positioned at two opposite sides of the insert 1, the first forming surface 20 is provided with a plurality of first movable holes 4, the second forming surface 30 is provided with a plurality of first movable holes 4, the first movable holes 4 are internally provided with positioning needles 5, the positioning needles 5 are in sliding fit with the inner walls of the first movable holes 4, the positioning needles 5 slide along the movable holes to be abutted against the insert 1, the positioning needles 5 arranged in the first movable holes 4 of the first forming surface 20 and the positioning needles 5 arranged in the first movable holes 4 of the second forming surface 30 are abutted against the insert 1 from two sides in the vertical direction, so that the displacement of the insert 1 in the forming cavity 6 is limited, the risk of cutting or collision between the insert 1 and the first die unit 2 or the second die unit 3 is reduced, and the risk of deformation or damage of the insert 1, the die and the molded product 10 caused by the displacement of the insert 1 is reduced.

Alternatively, as shown in fig. 3 to 4, the first movable hole 4 includes a first hole section 40 and a second hole section 41, the first hole section 40 is closer to the molding cavity 6 than the second hole section 41, the first hole section 40 has a smaller hole diameter than the second hole section 41, a step surface 42 is formed between the first hole section 40 and the second hole section 41, the positioning needle 5 is provided with a protrusion 50, the protrusion 50 is disposed around the positioning needle 5, and the protrusion 50 is located in the second hole section 41 and contacts with the step surface 42.

The positioning needle 5 may be in sliding engagement with the inner wall of the first bore section 40.

The protrusion 50 may be a sliding fit with the inner wall of the second bore section 41 or a gap may exist between the protrusion 50 and the inner wall of the second bore section 41.

The projections 50 extend from the outer peripheral surface of the positioning needle 5 in the radial direction of the positioning needle 5.

The protrusion 50 is located in the second hole section 41, and when the positioning pin 5 abuts against the insert 1, the protrusion 50 contacts the step surface 42, and the step surface 42 limits the protrusion 50 to move towards the forming cavity 6, so that the upper limit of the force applied to the insert 1 by the positioning element is limited, and the risk of damage to the insert 1 due to excessive extrusion of the positioning pin 5 is reduced.

Alternatively, as shown in fig. 1 to 4, a pressing plate 7 is disposed on one side of the first mold unit 2 and one side of the second mold unit 3, which are away from the molding cavity 6, the positioning needle 5 is further sleeved with an elastic member 51, and two ends of the elastic member 51 are respectively abutted to the protrusion 50 and the pressing plate 7.

Two pressing plates 7 may be in contact with the first mold unit 2 and the second mold unit 3, respectively.

The elastic member 51 may be, but is not limited to, a spring.

The pressing plate 7 may close the opening of the surface of the second hole section 41 extending to the first die unit 2 (or the second die unit 3), two ends of the elastic member 51 are respectively abutted with the protrusion 50 and the pressing plate 7, the positioning needle 5 can move towards the insert 1 under the pushing of the elastic force provided by the elastic member 51 until being abutted with the insert 1, when the injection molding is nearly completed, the fluid in the molding cavity 6 can apply a force opposite to the elastic force of the elastic member 51 to the positioning needle 5, when the force of the fluid in the molding cavity 6 applied to the positioning needle 5 is larger than the elastic force of the elastic member 51, the elastic member 51 is compressed by the force of the fluid in the molding cavity 6 applied to the positioning needle 5, the positioning needle 5 moves away from the molding cavity 6 along the first hole section 40 under the pushing of the force of the fluid, and the fluid can fill the inner space of the molding cavity 6 occupied by the positioning needle 5, so that the molded plastic material can completely wrap the part of the insert 1 located in the molding cavity 6.

Optionally, as shown in fig. 3 to 4, the pressing plate 7 is provided with a plurality of second movable holes 70, the second movable holes 70 are in one-to-one correspondence with the first movable holes 4, and one end of the positioning needle 5, which is away from the forming cavity 6, extends into the second movable holes 70.

The dimension of the second movable hole 70 in the vertical direction may be equal to the dimension of the portion of the positioning needle 5 between the end of the positioning needle 5 facing away from the molding cavity 6 and the convex portion, or the dimension of the second movable hole 70 in the vertical direction may be larger than the dimension of the portion of the positioning needle 5 between the end of the positioning needle 5 facing away from the molding cavity 6 and the convex portion.

One end of the positioning needle 5, which deviates from the forming cavity 6, extends into the second movable hole 70, when the positioning needle 5 is pushed by fluid in the forming cavity 6 to deviate from the forming cavity 6 to move, one end of the positioning needle 5, which deviates from the forming cavity 6, enters the second movable hole 70 until the protrusion 50 contacts with the pressing plate 7, the pressing plate 7 limits the positioning needle 5 to move continuously, and when the positioning needle 5 stops moving, one end of the positioning needle 5, which faces the forming cavity 6, can be flush with the first forming surface 20 (or the second forming surface 30) so as to block the communicating part of the first hole section 40 and the forming cavity 6, and the risk of redundant flash of the formed product 10 is reduced.

Optionally, as shown in fig. 3 to 4 and fig. 6 to 7, on the positioning needle 5, the part of the positioning needle 5 facing the forming cavity 6 is a first needle section 52, the part of the positioning needle 5 facing the pressing plate 7 is a second needle section 53, the first needle section 52 is at least partially located in the first hole section 40, and the second needle section 53 is at least partially located in the second movable hole 70, with the protrusion 50 as a separation.

The second needle section 53 is at least partially located in the second movable aperture 70, and when the protrusion 50 is in contact with the step surface 42 and the first needle section 52 abuts the insert 1, the second needle section 53 is at least partially located in the second movable aperture 70, reducing the risk of the second needle section 53 exiting the second movable aperture 70, enabling the second needle section 53 to remain located in the second movable aperture 70 during the back and forth movement of the positioning needle 5.

Alternatively, as shown in fig. 3 to 4, on the positioning needle 5, the diameter of the first needle section 52 is larger than that of the second needle section 53, and the inner wall of the second movable hole 70 is slidably engaged with the second needle section 53.

The inner wall of the second movable hole 70 is in sliding fit with the second needle section 53, so that on one hand, the second movable hole 70 limits the moving direction of the second needle section 53, the risk of the second needle section 53 deviating from the vertical direction is reduced, and on the other hand, the second needle section 53 can well seal the second movable hole 70.

Alternatively, as shown in fig. 6 to 7, a clamping groove 54 is formed at one end of the positioning needle 5 facing the forming cavity 6, and the clamping groove 54 is matched with the insert 1.

The edge of the insert 1 can be inserted into the catch groove 54 of the positioning pin 5.

The horizontal plane referred to in the present application is a plane perpendicular to the vertical plane.

The horizontal direction referred to in the present application includes a plurality of directions perpendicular to the vertical direction, and the horizontal direction is located at or parallel to the horizontal plane.

The extending direction of the clamping grooves 54 of the positioning pins 5 is parallel to the horizontal direction, the clamping grooves 54 of the positioning pins 5 clamp different parts of the insert 1 respectively, the clamping grooves 54 can limit the movement of the insert 1 on the horizontal plane in the direction perpendicular to the clamping grooves 54, the extending directions of the clamping grooves 54 of the positioning pins 5 can be mutually perpendicular, the movement of the clamping grooves 54 in the horizontal direction is limited, and the positioning effect on the insert 1 is improved.

Alternatively, as shown in fig. 3 and 6, the plurality of first movable holes 4 of the first mold unit 2 correspond in position to the plurality of first movable holes 4 of the second mold unit 3.

The positions of the first movable holes 4 of the first die unit 2 and the positions of the first movable holes 4 of the second die unit 3 are in one-to-one correspondence, any one of the first movable holes 4 of the first die unit 2 and the first movable hole 4 of the second die unit 3 corresponding to the position thereof are in one group, the force applied by the positioning needle 5 in each group of the movable holes to the insert 1 can be applied to the same area of the insert 1 so as to offset each other, and the risk that the shearing force damages the insert 1 is formed by staggering the force applied by the positioning needle 5 in the first movable hole 4 of the first die unit 2 and the force applied by the positioning needle 5 in the first movable hole 4 of the second die unit 3 to the insert 1 is reduced.

Optionally, as shown in fig. 6 to 7, the mold further comprises an insert 8, wherein a positioning groove for fixing the insert 8 is formed in the inner wall of the molding cavity 6, and the insert 8 is used for mounting the insert 1.

Part of the end of the metal insert 1 in the electronic component needs to be exposed to the outside, which part can be inserted into the insert 8, so that the insert 1 is suspended in the molding cavity 6.

While the application has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the application. In particular, the technical features mentioned in the respective embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.

Claims (9)

1. A mold for in-mold injection molding of an insert, comprising:

a first die unit including a first molding surface provided with a plurality of first movable holes;

a second die unit including a second molding surface provided with a plurality of the first movable holes;

The positioning needle is in sliding fit with the inner wall of the first movable hole;

The first molding surface and the second molding surface enclose a molding cavity for injection molding, the insert is placed inside the molding cavity, and one end of the positioning needle is abutted to the insert.

2. The mold of claim 1, wherein the first movable bore comprises a first bore section and a second bore section, the first bore section being smaller in bore diameter than the second bore Duan Kaojin than the molding cavity, a step surface being formed between the first bore section and the second bore section, the positioning pin being provided with a protrusion, the protrusion being disposed around the positioning pin, the protrusion being located within the second bore section and in contact with the step surface.

3. The mold according to claim 2, wherein the first mold unit and the second mold unit are each provided with a pressing plate on a side facing away from the molding cavity, the positioning needle is further sleeved with an elastic member, and both ends of the elastic member are respectively abutted against the protrusion and the pressing plate.

4. A mould according to claim 3, wherein the pressure plate is provided with a plurality of second movable holes, the second movable holes are in one-to-one correspondence with the first movable holes, and one end of the positioning needle, which is away from the forming cavity, extends into the second movable holes.

5. The mold of claim 4, wherein the positioning pin is separated by the protrusion, the portion of the positioning pin facing the molding cavity is a first pin segment, the portion of the positioning pin facing the platen is a second pin segment, the first pin segment is at least partially positioned within the first hole segment, and the second pin segment is at least partially positioned within the second movable hole.

6. The mold of claim 5, wherein on the positioning pin, the diameter of the first pin segment is larger than the diameter of the second pin segment, and the inner wall of the second movable bore is in sliding fit with the second pin segment.

7. The mold of claim 1, wherein the end of the positioning pin facing the molding cavity is provided with a clamping groove, and the clamping groove is matched with the insert.

8. The mold of claim 1, wherein the plurality of first movable bores of the first mold unit correspond to the plurality of first movable bores of the second mold unit.

9. The mold of claim 1, further comprising an insert, wherein an inner wall of the molding cavity is provided with a positioning groove for fixing the insert, the insert being used for installation of the insert.