CN220904160U

CN220904160U - Connecting hole injection molding structure, injection molding piece and electrical equipment

Info

Publication number: CN220904160U
Application number: CN202322510012.6U
Authority: CN
Inventors: 汪续宗; 刘芳; 刘亚运; 刘国荣
Original assignee: NVC Lighting Technology Corp
Current assignee: NVC Lighting Technology Corp
Priority date: 2023-09-14
Filing date: 2023-09-14
Publication date: 2024-05-07
Anticipated expiration: 2033-09-14

Abstract

The utility model provides a connecting hole injection molding structure, an injection molding part and electrical equipment, wherein the connecting hole injection molding structure comprises a body, a connecting hole is formed in the body, the connecting hole comprises a straight hole and a counter bore, the straight hole is provided with a plurality of connecting walls and a plurality of waste tanks, the connecting walls and the waste tanks are distributed at intervals along the circumferential direction of the straight hole, inscribed circles are arranged among the connecting walls, the waste tanks are recessed from the connecting walls back to the axle center of the straight hole, when an internal thread is formed in the straight hole, the maximum distance between the waste tanks and the axle center is larger than the external diameter of the internal thread, the diameter of the inscribed circles is smaller than or equal to the internal diameter of the internal thread, the counter bore is positioned at the inlet end of the straight hole, the first depth of the counter bore is smaller than the second depth of the straight hole, the first cross section of the counter bore is in the shape of a round angle, and the projection of the straight hole is positioned in the projection of the counter bore on the first cross section. The injection molding piece is provided with the connecting hole injection molding structure, the electrical equipment comprises the injection molding piece, and the connecting hole injection molding structure has the advantage of preventing the screw from bursting and sliding teeth in the assembling process.

Description

Connecting hole injection molding structure, injection molding piece and electrical equipment

Technical Field

The utility model relates to the technical field of injection molding, in particular to a connecting hole injection molding structure, an injection molding provided with the connecting hole injection molding structure and electrical equipment comprising the injection molding.

Background

In order to meet the assembly requirement of products, an injection molding structure with connecting holes is generally formed on an existing injection molding part through an injection molding process, so that the injection molding part can be assembled with other parts of the products through the connecting holes in the injection molding structure. As shown in fig. 1, it shows a conventional injection molding structure 9, where a connecting hole 91 on the injection molding structure 9 is a cylindrical hole, when an injection molding part is assembled with other parts of a product, a screw is first inserted through a through hole on the part assembled with the injection molding part, and then the screw is screwed with the connecting hole 91 on the injection molding part, so as to realize fixed connection between the injection molding part and the other parts of the product through the screw. However, in the process of screwing the screw into the connecting hole 91, the thread structure on the screw rod of the screw cuts the hole wall of the connecting hole 91, so that cutting scraps are generated, and the generated cutting scraps are accumulated in the connecting hole 91, so that the screwing resistance of the screw and the extrusion force born by the injection molding structure 9 are increased, and when the screwing resistance is excessive, sliding teeth appear on the thread formed in the connecting hole 91, thereby affecting the fastening performance of the screw; in addition, under the dual effects of cutting waste accumulation and increasing screwing resistance, the injection molding structure 9 and the connecting hole 91 on the injection molding structure are extremely easy to burst, so that injection molding parts are scrapped, the waste output and the production cost are increased, and meanwhile, the production efficiency is also reduced; furthermore, the diameter of the fixed end of the screw (the end of the screw close to the screw head) of the existing screw is larger than the diameter of the free end of the screw (the end of the screw far from the screw head), so that when the fixed end of the screw is screwed into the entrance end of the connecting hole 91, the risk of bursting of the injection structure 9 and the connecting hole 91 thereon is increased.

Disclosure of Invention

In order to solve the above problems, the main object of the present utility model is to provide a connecting hole injection molding structure capable of preventing the screw from bursting and sliding during the assembling process.

Another object of the present utility model is to provide an injection molding member provided with the above-mentioned connecting hole injection molding structure.

It is a further object of the present utility model to provide an electrical device comprising the injection molded part as described above.

In order to achieve the main purpose of the utility model, the utility model provides a connecting hole injection molding structure, which comprises a body, wherein a connecting hole is formed in the body, the connecting hole comprises a straight hole and a counter bore, the straight hole is provided with a plurality of connecting walls and a plurality of waste tanks, the connecting walls and the waste tanks are distributed at intervals along the circumferential direction of the straight hole, inscribed circles are arranged between the connecting walls, the waste tanks are recessed from the connecting walls back to the axle center of the straight hole, when an internal thread is formed in the straight hole, the maximum distance between the waste tanks and the axle center is larger than the external diameter of the internal thread, the diameter of the inscribed circle is smaller than or equal to the internal diameter of the internal thread, the counter bore is positioned at the inlet end of the straight hole, the first depth of the counter bore is smaller than the second depth of the straight hole, the first cross section of the counter bore is in the shape of a round angle, and the projection of the straight hole is positioned in the projection of the counter bore.

From the above, through the design of the injection molding structure of the connecting hole, when the screw is assembled into the connecting hole, the screw rod of the screw cuts the connecting wall of the straight hole to establish threaded connection with the connecting wall, and the cut waste is brought into and stored into the waste tank along with the rotation of the screw, so that the cutting waste is prevented from obstructing the screwing of the screw and increasing the extrusion force born by the injection molding structure of the connecting hole, and the injection molding structure of the connecting hole is prevented from sliding and/or bursting in the process of loading the screw into the connecting hole; in addition, the countersink is used for holding the stiff end of the screw (the end of the screw close to the screw head) of the screw for do not take place to contact between stiff end and the countersink of screw, in order to avoid when the stiff end of screw is screwed into the entry end department (i.e. countersink department) of connecting hole, the stiff end extrusion connecting hole of screw and make the connecting hole injection structure appear bursting.

Preferably, the second cross section of the straight bore is rounded square.

From the above, the fillet of straight hole is accomodate the cutting waste material that produces in the screw assembly process as the waste material groove, and straight flange wall then is used for the screw to carry out the cooperation to be connected for can reduce the cutting waste material that produces in the screw assembly process when guaranteeing to carry out reliable cooperation with the screw, reduce the risk that the connecting hole injection structure sliding tooth and/or burst.

The further scheme is that the counter bore is similar to a quadrangular frustum pyramid, and the small-bore end of the counter bore is completely overlapped with the inlet end of the straight bore.

From the above, the design enables smooth transition between the straight hole and the pore-forming, and the counter bore can play a certain guiding role on the screw rod of the screw in the screw assembling process.

Another preferable scheme is that the second cross section of the straight hole is similar to a chrysanthemum shape, and the counter bore is similar to a quadrangular prism shape; the number of the connecting walls is three to eight, and the number of the waste tanks is three to eight.

From the above, through the shape design of the straight hole, under the condition that the injection structure of the connecting hole is limited, screws with different screw diameters can be adapted by adjusting the shape of the straight hole, so that the practicability and the adaptation range of the injection structure of the connecting hole are improved; through the quantity design to connecting wall, waste bin, under the circumstances of guaranteeing that screw and connecting hole carry out effective, reliable fixed connection, can make the structure of connecting hole more optimize, reasonable, and be convenient for production and processing.

Further, the connecting wall is plane; or the connecting wall is an arc surface, the arc surface protrudes towards the axle center or the arc surface is recessed away from the axle center.

From the above, the shape of the connecting wall can be selected according to the screw diameter of the screw to be adapted, so as to ensure that the screw and the connecting hole are reliably and fixedly connected, and the practicability and the adaptation range of the injection molding structure of the connecting hole are improved.

In a further scheme, a chamfer is arranged at the inlet end of the counter bore, and the chamfer is a round chamfer or a chamfer angle.

From the above, the design can avoid the excessive concentration of stress at the entrance of the counter bore, is more beneficial to the molding of the counter bore, and reduces the defective rate and the rejection rate of the connecting hole injection molding structure.

In a further scheme, the connecting hole injection molding structure further comprises more than two reinforcing ribs, and the more than two reinforcing ribs are distributed on the circumference of the body and connected with the body.

From the above, the setting of stiffening rib can promote the intensity of connecting hole injection structure to the structural design of auxiliary connecting hole is in order to prevent connecting hole injection structure burst to a certain extent.

In order to achieve another object of the present utility model, the present utility model provides an injection molding member, which has a main body, wherein the injection molding member further has the above-mentioned connecting hole injection molding structure, and the main body are integrally formed.

From the above, the injection molding part is provided with the connecting hole injection molding structure, so that when the injection molding part is assembled with a screw, the resistance born by the screw in the assembling process is reduced, and the sliding teeth and/or bursting of the connecting hole injection molding structure in the screw assembling process are effectively prevented, so that the rejection rate and the reject ratio of products generated in the assembling process are reduced.

The number of the connecting hole injection molding structures is more than two.

From the above, the design ensures that the injection molding part can be firmly and reliably fixedly connected with other parts, and simultaneously ensures that the injection molding part can be firmly connected with other parts when a certain connecting hole injection molding structure carelessly generates sliding teeth and/or bursting in the screw assembly process so as to reduce the rejection rate and the reject rate of products generated in the assembly process; in addition, the design can also enable the same injection molding piece to have the capability of adapting to parts with different parameter specifications (such as different sizes, different manufacturer production, different shape structures and the like), so that the adaptation range of the injection molding piece is enlarged.

In order to achieve the further object of the utility model, the utility model provides electrical equipment, which comprises an assembly part and a screw, wherein the assembly part is provided with a through hole, the through hole penetrates through the assembly part, and a screw rod of the screw penetrates through the through hole, wherein the electrical equipment further comprises the injection molding part, the screw rod penetrates through a counter bore and is connected with a connecting wall, and the assembly part is adjacent between the injection molding structure of the connecting hole and the head part of the screw.

From the above, the electrical equipment provided with the injection molding part can reduce the rejection rate and the product reject ratio in the assembly process, save the production cost and optimize the product.

Drawings

Fig. 1 is a structural view of a conventional injection molding structure of a connecting hole.

Fig. 2 is a block diagram of a first view of a first embodiment of the connecting hole injection structure of the present utility model.

Fig. 3 is a structural view of the first embodiment of the connecting hole injection structure of the present utility model at a second view angle.

Fig. 4 is a cross-sectional view of a first embodiment of the connecting hole injection structure of the present utility model.

Fig. 5 is a partial construction view of a second embodiment of the connecting hole injection structure of the present utility model.

Fig. 6 is a block diagram of a first chrysanthemum-shaped straight hole of a second embodiment of the connecting hole injection structure of the present utility model.

Fig. 7 is a block diagram of a second type of straight, chrysanthemum-shaped hole in a second embodiment of the connecting hole injection structure of the present utility model.

Fig. 8 is a structural view of a third chrysanthemum-shaped straight hole of the second embodiment of the connecting hole injection structure of the present utility model.

Fig. 9 is a structural view of a fourth chrysanthemum-shaped straight hole of the second embodiment of the connecting hole injection structure of the present utility model.

The utility model is further described below with reference to the drawings and examples.

Detailed Description

First embodiment of connecting hole injection Structure

Referring to fig. 2 to 4, the connection hole injection molding structure 100 includes a body 1, a connection hole 11 is formed on the body 1, and the connection hole 11 is used for the screw 101 to perform the mating connection. Wherein the connection hole 11 includes a straight hole 111 and a counter bore 112, and the counter bore 112 is located at an inlet end of the straight hole 111. The straight hole 111 is used for matching connection of the screw rod 1011 of the screw 101 so as to fix the screw 101 on the connecting hole injection molding structure 100; the counter bore 112 plays a role of avoiding the fixed end of the screw 1011 of the screw 101 (the end of the screw 1011 near the head 1012 of the screw 101) so as to avoid the contact between the fixed end of the screw 1011 and the connecting hole 11, thereby preventing the fixed end of the screw 1011 from extruding the connecting hole 11 and bursting the connecting hole injection structure 100 when the fixed end of the screw 1011 is screwed into the inlet end of the connecting hole 11 (i.e., the counter bore 112). In addition, the first depth of the counter bore 112 is smaller than the second depth of the straight bore 111, so that effective and reliable fixed connection can be performed between the stem 1011 of the screw 101 and the straight bore 111.

The straight hole 111 has a plurality of connection walls 1111 and a plurality of waste tanks 1112, and the connection walls 1111 and the waste tanks 1112 are equal in number, and the plurality of connection walls 1111 and the plurality of waste tanks 1112 are spaced apart in the circumferential direction of the straight hole 111. The connecting wall 1111 is used for the matching connection of the screw rod 1011 of the screw 101; wherein, a plurality of connecting walls 1111 have an inscribed circle therebetween so that each connecting wall 1111 can be coupled with the screw 1011 in a mating manner.

The waste tank 1112 is recessed from the connecting wall 1111 away from the axial center of the straight hole 111 so that the distance between the waste tank 1112 and the center of the inscribed circle is larger than the diameter of the inscribed circle. When the internal thread is formed in the straight hole 111, the maximum distance between the waste groove 1112 and the axis is larger than the external diameter of the internal thread, so that the waste groove 1112 can store cutting waste generated in the process of assembling the screw 101 and the connecting hole 11, further, the cutting waste is prevented from obstructing the screwing of the screw 101 and increasing the extrusion force of the connecting hole injection molding structure 100, and the screw 101 is prevented from sliding and/or bursting in the process of loading the screw 101 into the connecting hole 11; in addition, the diameter of the inscribed circle is smaller than or equal to the inner diameter of the internal thread of the screw 1011 to ensure the reliability and the firmness of the connection wall 1111 with the screw 1011.

The counterbore 112 is preferably coaxially disposed with the straight bore 111, and the first cross section of the counterbore 112 is preferably rounded square; on the first cross section, the projection of the straight bore 111 is located within the projection of the counterbore 112, i.e. the bore diameter of the counterbore 112 is larger than the diameter of the shank 1011 of the screw 101. In this embodiment:

The second cross section of the straight hole 111 is in a round square shape, wherein the round angle of the straight hole 111 is used as a waste groove 1112 to store cutting waste generated in the assembly process of the screw 101, and the straight-edge wall surface is used as a connecting wall 1111 for the matched connection of the screw 101; through the shape design to straight hole 111 for under the prerequisite of guaranteeing that it carries out reliable cooperation with screw 101, the cutting waste material that produces in the screw 101 assembly process that can be better reduces connecting hole injection structure 100 sliding tooth and/or the risk of bursting.

The counter bore 112 is similar to a quadrangular frustum, and the small-bore end of the counter bore 112 is completely overlapped with the inlet end of the straight bore 111. The design enables smooth transition between the straight hole 111 and the hole forming, and meanwhile, the counter bore 112 can play a certain guiding role on the screw rod 1011 of the screw 101 in the assembly process of the screw 101.

Preferably, the connecting hole injection molding structure 100 further includes more than two reinforcing ribs 2, and the more than two reinforcing ribs 2 are distributed in the circumferential direction of the body 1 and connected with the body 1. The provision of the reinforcing ribs 2 can enhance the strength of the connection hole injection molding structure 100, thereby assisting the structural design of the connection hole 11 to a certain extent to prevent the connection hole injection molding structure 100 from bursting.

The assembly of screw 101 with connecting hole injection structure 100 is briefly described as follows:

When the screw 101 is screwed into the connection hole 11 of the connection hole injection structure 100, the screw 1011 of the screw 101 passes through the counter bore 112 first and then contacts the connection wall 1111 of the straight hole 111 (as in the present embodiment, the straight-side wall surface of the straight hole 111).

As the screw 101 is screwed in, the shank 1011 of the screw 101 cuts the respective connection walls 1111 with the cutting tail of the screw thread on itself to form an internal thread on each connection wall 1111; in the process of cutting the connecting wall 1111 of the screw thread of the screw 1011, the waste generated by cutting enters each waste groove 1112 (such as the round angle of the straight hole 111 in the embodiment) under the rotation drive of the screw 101, so as to store the waste, prevent the waste from accumulating between the connecting wall 1111 and the screw 1011, effectively reduce the resistance of the screw 101 when screwing in and the extrusion force of the straight hole 111, and prevent the screw 101 from sliding the straight hole 111 and/or the generated cutting waste from extruding the wall of the connecting hole 11 to crack the connecting hole injection molding structure 100.

When the screw 101 is assembled in place, the fixed end of the screw 1011 of the screw 101 is positioned in the counter bore 112 and is not in contact with the counter bore 112, so that the connecting hole injection molding structure 100 is prevented from being cracked due to the fact that the fixed end of the screw 1011 presses the hole wall of the connecting hole 11.

In summary, through the design to the connecting hole injection molding structure 100 for the cutting waste material that produces in the screw 101 and the connecting hole injection molding structure 100 assembly process can be accomodate through the waste material groove 1112, prevent that the cutting waste material from obstructing the screw 101's screw-in, and reduce the extrusion force that the connecting hole injection molding structure 100 receives, thereby avoid screw 101 to pack into connecting hole 11 in-process connecting hole injection molding structure 100 to appear smooth tooth and/or burst.

Second embodiment of connecting hole injection Structure

The present embodiment is different from the first embodiment of the connecting hole injection structure in the shape of the connecting hole, specifically, in combination with fig. 5 to 9, in the present embodiment:

The second cross section of the straight hole 31 is similar to a chrysanthemum shape, and the counter bore 32 is similar to a quadrangular prism shape; the number of the connection walls 311 is three to eight, and the number of the waste tanks 312 is three to eight. Through the shape design of the straight hole 31, under the condition that the injection structure of the connecting hole is limited, screws with different screw diameters can be adapted by adjusting the shape of the straight hole 31, so that the practicability and the adaptation range of the injection structure of the connecting hole are improved; through the quantity design to connecting wall 311, chute 312, under the circumstances of guaranteeing that the screw carries out effective, reliable fixed connection with connecting hole 3, can make the structure of connecting hole 3 more optimize, reasonable, and be convenient for production and processing. Wherein, the chrysanthemum-like shape generally refers to a rounded polygon or a deformed rounded polygon (the aforementioned "deformation" generally refers to that the sides of the polygon are arc segments rather than straight segments, or the sides of the polygon are a combination of arc segments and straight segments).

Preferably, the counterbore 32 is provided with a chamfer 321 at its inlet end; wherein the chamfer 321 is a rounded or beveled corner. The arrangement of the chamfer 321 can avoid too concentrated stress at the inlet of the counter bore 32, is more beneficial to the molding of the counter bore 32, and reduces the defective rate and the rejection rate of the connecting hole injection molding structure.

As shown in fig. 6, the connecting walls 311 are plane 3111, and the number of connecting walls 311 and the number of waste tanks 312 are five, so that the second cross section of the straight hole 31 is rounded pentagon; the connecting wall 311 corresponds to the aforementioned "rounded polygon" side, which is a straight line segment, on the second cross section of the straight hole 31.

As shown in fig. 7, the connecting walls 311 are plane 3111, and the number of connecting walls 311 and the number of waste tanks 312 are four, and the connecting walls 311 are protruded toward the axis of the straight hole 31, so that the second cross section of the straight hole 31 is similar to a chrysanthemum; the connecting wall 311 corresponds to the aforementioned "deformed rounded polygon" side, which is a combination of an arc segment and a straight segment, on the second cross section of the straight hole 31.

As shown in fig. 8, the connecting wall 311 is a cambered surface 3112, and the cambered surface 3112 protrudes toward the axis of the straight hole 31, and the number of the connecting walls 311 and the number of the waste tanks 312 are four, so that the second cross section of the straight hole 31 is in another chrysanthemum shape; the connecting wall 311 corresponds to the aforementioned "deformed rounded polygon" side, which is an arc section, on the second cross section of the straight hole 31.

As shown in fig. 9, the connecting wall 311 is a cambered surface 3112, and the cambered surface 3112 is recessed away from the axis of the straight hole 31, and the number of the connecting walls 311 and the number of the waste tanks 312 are three, so that the second cross section of the straight hole 31 is of a chrysanthemum shape; the connecting wall 311 corresponds to the aforementioned "deformed rounded polygon" side, which is an arc section, on the second cross section of the straight hole 31.

It can be seen that the shape of the connecting wall 311 can be selected according to the screw diameter of the screw to be adapted, so as to ensure that the screw is reliably and fixedly connected with the connecting hole 3, and improve the practicality and the adaptation range of the injection molding structure of the connecting hole 3. Since the specific shape of the straight hole 31 is diversified, the shape of the straight hole 31 will not be described in detail herein.

Injection molded part embodiment

The injection molding piece is provided with a main body and a connecting hole injection molding structure, wherein the connecting hole injection molding structure is the connecting hole injection molding structure generally described in the first embodiment or the second embodiment of the connecting hole injection molding structure; the main body and the body are integrally formed. The injection molding part is provided with the connecting hole injection molding structure, so that when the injection molding part is assembled with a screw, the resistance born by the screw in the assembling process is reduced, and the sliding teeth and/or bursting of the connecting hole injection molding structure in the screw assembling process are effectively prevented, so that the rejection rate and the reject rate of products generated in the assembling process are reduced.

Preferably, the number of the injection molding structures of the connecting holes is more than two, so that the injection molding parts can be firmly and reliably fixedly connected with other parts, and meanwhile, when sliding teeth and/or bursting occur carelessly in the screw assembling process of a certain injection molding structure of the connecting holes, the injection molding parts can still be firmly connected with other parts, so that the rejection rate and the reject rate of products generated in the assembling process are reduced; in addition, the design can also enable the same injection molding piece to have the capability of adapting to parts with different parameter specifications (such as different sizes, different manufacturer production, different shape structures and the like), so that the adaptation range of the injection molding piece is enlarged.

Electrical device embodiment

The electrical equipment comprises an assembly part, a screw and an injection molding part, wherein the assembly part is provided with a through hole, and the through hole penetrates through the assembly part; wherein the injection molding is the injection molding described in the injection molding embodiment. When the assembly part, the screw and the injection molding part are assembled, the screw rod of the screw passes through the through hole, then passes through the counter bore on the injection molding structure of the connecting hole on the injection molding part, and is connected with the connecting wall of the straight hole; when the assembly of the fitting, screw and injection molded part is completed, the fitting abuts between the connecting hole injection molded structure and the head of the screw.

The electrical equipment can be a lamp, a bathroom heater, a summer heater, a fan, an air conditioner or a television, etc., so the type of the electrical equipment is not described in an exhaustive manner; the electrical equipment provided with the injection molding part can reduce the rejection rate and the product reject rate in the assembly process, save the production cost and optimize the product.

Finally, it should be emphasized that the foregoing description is merely illustrative of the preferred embodiments of the utility model, and that various changes and modifications can be made by those skilled in the art without departing from the spirit and principles of the utility model, and any such modifications, equivalents, improvements, etc. are intended to be included within the scope of the utility model.

Claims

1. Connecting hole injection structure, including the body, the shaping has the connecting hole on the body, its characterized in that, the connecting hole includes:

The straight hole is provided with a plurality of connecting walls and a plurality of waste tanks, the connecting walls and the waste tanks are distributed at intervals along the circumferential direction of the straight hole, inscribed circles are arranged among the connecting walls, the waste tanks are recessed from the connecting walls back to the axle center of the straight hole, when internal threads are formed in the straight hole, the maximum distance between the waste tanks and the axle center is larger than the external diameter of the internal threads, and the diameter of the inscribed circles is smaller than or equal to the internal diameter of the internal threads;

The counter bore is located the entry end of straight hole, the first degree of depth of counter bore is less than the second degree of depth of straight hole, the first transversal section of counter bore personally submits the fillet square, on the first transversal section, the projection of straight hole is located in the projection of counter bore.

2. The connecting hole injection molding structure according to claim 1, wherein:

the second cross section of the straight hole is round-corner square.

3. The connecting hole injection molding structure according to claim 2, wherein:

the counter bore is similar to a quadrangular frustum pyramid, and the small-bore end of the counter bore is completely overlapped with the inlet end of the straight hole.

4. The connecting hole injection molding structure according to claim 1, wherein:

the second cross section of the straight hole is similar to a chrysanthemum shape, and the counter bore is similar to a quadrangular prism shape;

the number of the connecting walls is three to eight, and the number of the waste tanks is three to eight.

5. The connecting hole injection molded structure of claim 4, wherein:

the connecting wall is plane; or (b)

The connecting wall is an arc surface, and the arc surface is convex towards the axle center or is concave away from the axle center.

6. The connecting hole injection molded structure according to claim 4 or 5, wherein:

The inlet end of the counter bore is provided with a chamfer, and the chamfer is a round chamfer or a chamfer angle.

7. The connecting hole injection molded structure according to any one of claims 1 to 5, wherein:

The connecting hole injection molding structure further comprises more than two reinforcing ribs, and the more than two reinforcing ribs are distributed on the circumference of the body and connected with the body.

8. Injection molded part having a main body, characterized by further having a connecting hole injection molded structure according to any one of claims 1 to 7, the main body being integrally molded with the main body.

9. An injection molded article according to claim 8, wherein:

10. The electrical equipment comprises an assembly part and a screw, wherein a through hole is formed in the assembly part, the through hole penetrates through the assembly part, and a screw rod of the screw penetrates through the through hole, and the electrical equipment is characterized in that:

The electrical device further comprising an injection molded part according to claim 8 or 9, wherein the threaded rod is connected to the connecting wall after passing through the counterbore, and wherein the fitting is abutted between the connecting hole injection molded structure and the head of the screw.