CN111168607A

CN111168607A - Clamp for assisting electronic equipment shell assembly

Info

Publication number: CN111168607A
Application number: CN202010060170.4A
Authority: CN
Inventors: 朱伟
Original assignee: Oppo Chongqing Intelligent Technology Co Ltd
Current assignee: Oppo Chongqing Intelligent Technology Co Ltd
Priority date: 2020-01-19
Filing date: 2020-01-19
Publication date: 2020-05-19

Abstract

The application provides a anchor clamps for assisting electronic equipment casing equipment, this anchor clamps include: the device comprises a workbench, a bottom template and an auxiliary positioning plate; the workbench is provided with a bearing surface; the bottom template is fixed on the bearing surface and is provided with a profile groove used for accommodating semi-finished electronic equipment of the shell to be assembled; the auxiliary positioning plate is detachably connected with the workbench through a connecting mechanism; the auxiliary positioning plate is provided with a through positioning groove which is arranged opposite to the profiling groove on the bottom template; the locating slot is used for placing a shell to be assembled, and the shell to be assembled can be assembled on the semi-finished electronic equipment of the shell to be assembled in the profiling slot of the bottom template under the guidance of the locating slot. The clamp has the characteristics of simple structure, low cost and convenience in operation, greatly improves the assembly efficiency of the battery cover, and can also avoid the condition that other parts are polluted or damaged in the assembly process.

Description

Clamp for assisting electronic equipment shell assembly

Technical Field

The invention relates to the technical field of auxiliary tools in the assembly and production process of electronic equipment, in particular to a clamp for assisting the assembly of a shell of the electronic equipment.

Background

The casing of an electronic device such as a mobile phone and a tablet computer generally includes a rear cover (or a battery cover), and the battery cover is often a last mounting process after other components of the electronic device are assembled. In the process of assembling the battery cover, the conventional technology generally adopts two modes: one is purely manual assembly, which has the disadvantage that during the assembly process the operator's fingers easily touch the already assembled screen, causing it to be soiled; the process of cleaning the screen is carried out after the screen is dirtied, which increases the uncertainty of the assembly process and reduces the efficiency of the assembly production; the battery cover is assembled by pure hands without positioning, and is buckled by experience and feeling, so that the battery cover is easily buckled, scratched and scratched, and the quality stability of an assembled finished product is poor; the other method is to use a fully automatic battery cover assembling device, which has the disadvantages that the price of the fully automatic battery cover assembling device and the later maintenance cost are high, which increases the cost of the assembling production process, and in addition, once the fully automatic battery cover assembling device is damaged, the maintenance period is long, which affects the progress of the assembling work.

Disclosure of Invention

The embodiment of the application provides a anchor clamps for assisting electronic equipment casing equipment, anchor clamps include:

the workbench is provided with a bearing surface;

the bottom template is fixed on the bearing surface and provided with a contour groove, and the contour groove is used for accommodating semi-finished electronic equipment of the shell to be assembled;

the auxiliary positioning plate is detachably connected with the workbench through a connecting mechanism; the auxiliary positioning plate is provided with a through positioning groove, and the positioning groove is opposite to the profiling groove on the bottom template; the positioning groove is used for placing a shell to be assembled, and the shell to be assembled can be assembled on the semi-finished electronic equipment of the shell to be assembled in the copying groove of the bottom template under the guidance of the positioning groove.

According to the clamp for assisting the assembly of the electronic equipment shell, the base template and the auxiliary positioning plate which are aligned are arranged on the workbench, the semi-finished electronic equipment of the shell to be assembled is firstly placed in the profile groove of the base template, and then the shell to be assembled is assembled on the semi-finished electronic equipment of the shell to be assembled in the profile groove of the base template under the guidance of the positioning groove of the auxiliary positioning plate; the clamp has the characteristics of simple structure, low cost and convenience in operation, and the assembly efficiency of the battery cover is greatly improved; compared with the pure manual assembly, the assembly difficulty of the battery cover is greatly reduced, the positioning precision is high, the assembly yield is improved, and the requirement on operators (or operation manipulators) is reduced; contamination and damage to other components during assembly can also be avoided.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic diagram illustrating an overall structure of an embodiment of a fixture for assisting in assembling a housing of an electronic device according to the present application;

FIG. 2 is a schematic view of the clamp of the embodiment of FIG. 1 in a disassembled configuration;

FIG. 3 is a schematic view of the clamp of the embodiment of FIG. 1 from another perspective;

FIG. 4 is an enlarged view of a portion of the structure at A in FIG. 3;

FIG. 5 is a schematic partial structure break away at A in FIG. 3;

FIG. 6 is a schematic view of the positioning clip;

FIG. 7 is a schematic view of the mating structure of the bottom form and the stop assembly;

FIG. 8 is an enlarged schematic view of the structure at B in FIG. 7;

FIG. 9 is a schematic diagram of FIG. 8 with the structure broken away;

FIG. 10 is a schematic view of the abutment unit of FIG. 9;

FIG. 11 is a schematic view of a portion of the bottom form of FIG. 7;

FIG. 12 is a schematic view of the structure of the auxiliary positioning plate cooperating with the auxiliary guide unit;

FIG. 13 is an enlarged view of a portion of the structure at C in FIG. 12;

fig. 14 is a schematic structural view of the auxiliary guide unit of fig. 13.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be noted that the following examples are only illustrative of the present invention, and do not limit the scope of the present invention. Likewise, the following examples are only some but not all examples of the present invention, and all other examples obtained by those skilled in the art without any inventive step are within the scope of the present invention.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the phrase 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. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

As used herein, an "electronic device" (or simply "terminal") includes, but is not limited to, an apparatus that is configured to receive/transmit communication signals via a wireline connection, such as via a Public Switched Telephone Network (PSTN), a Digital Subscriber Line (DSL), a digital cable, a direct cable connection, and/or another data connection/network, and/or via a wireless interface (e.g., for a cellular network, a Wireless Local Area Network (WLAN), a digital television network such as a DVB-H network, a satellite network, an AM-FM broadcast transmitter, and/or another communication terminal). A communication terminal arranged to communicate over a wireless interface may be referred to as a "wireless communication terminal", "wireless terminal" or "mobile terminal". Examples of mobile terminals include, but are not limited to, satellite or cellular telephones; a Personal Communications System (PCS) terminal that may combine a cellular radiotelephone with data processing, facsimile and data communications capabilities; PDAs that may include radiotelephones, pagers, internet/intranet access, Web browsers, notepads, calendars, and/or Global Positioning System (GPS) receivers; and conventional laptop and/or palmtop receivers or other electronic devices that include a radiotelephone transceiver. A cellular phone is an electronic device equipped with a cellular communication module.

Referring to fig. 1 and fig. 2 together, fig. 1 is a schematic overall structure diagram of an embodiment of a fixture for assisting in assembling a housing of an electronic device according to the present application, and fig. 2 is a schematic disassembled structure diagram of the fixture in the embodiment of fig. 1; it should be noted that the fixture in the present application is used for assisting the assembly of the electronic device housing, especially the assembly of the rear case (battery cover) of the electronic device, where the electronic device may include a mobile phone, a tablet computer, a notebook computer, a wearable device, and the like. The fixture for assisting the electronic device housing assembly in the embodiment includes, but is not limited to, the following structural components: a table 100, a bottom mold plate 200, and an auxiliary positioning plate 300. It should be noted that the terms "comprises" and "comprising," and any variations thereof, in the embodiments of the present application, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or may alternatively include other steps or elements inherent to such process, method, article, or apparatus.

Specifically, the workbench 100 is provided with a bearing surface 110, the bottom plate 200 is fixed on the bearing surface 110, the bottom plate 200 is provided with a contour groove 210, the contour groove 210 is used for accommodating a semi-finished electronic device 55 of the casing to be assembled, wherein the semi-finished electronic device 55 of the casing to be assembled can be a structural component which is assembled to a display screen and a circuit board, a battery and the like inside the casing, and the clamp in the embodiment of the present application is mainly used for guiding the assembly of a battery cover (a rear cover).

Optionally, the auxiliary positioning plate 300 is detachably connected to the workbench 100 through a connecting mechanism 400; the auxiliary positioning plate 300 is provided with a through positioning groove 310, and the positioning groove 310 is arranged opposite to the profiling groove 210 on the bottom template 200; specifically, the auxiliary positioning plate 300 is disposed over the bottom mold plate 200 in a suspended manner. The positioning slot 310 is used for placing a casing (not shown) to be assembled, in this embodiment, a rear case of an electronic device; the housing to be assembled can be fitted on the semi-finished electronic device 55 of the housing to be assembled in the contour groove 210 of the bottom mold plate 200 under the guidance of the positioning groove 310.

A positioning column 120 is disposed on the bearing surface 110 of the working table 100, a positioning hole 320 is disposed on the auxiliary positioning plate 300, and the positioning hole 320 is used for matching with the positioning column 120 to realize that the positioning groove 310 of the auxiliary positioning plate 300 is disposed opposite to the profiling groove 210 of the bottom mold plate 200. Optionally, in this embodiment, the number of the positioning pillars 120 is four, and the number of the positioning holes 320 corresponds to that of the positioning pillars; the positioning posts 120 are uniformly distributed around the four corners of the bottom mold plate 200. Of course, in some other embodiments, the number of the positioning pillars 120 may also be 2 or more, and is not limited herein.

Referring to fig. 3 to 5, fig. 3 is a schematic structural view of the clamp shown in fig. 1 from another view, and fig. 4 is an enlarged view of a portion a in fig. 3; FIG. 5 is a schematic partial structure break away at A in FIG. 3; the connecting mechanism 400 includes a positioning clip 410 rotatably connected to the auxiliary positioning plate 300 and a fastening portion 420 fixedly disposed on the worktable, and the positioning clip 410 is engaged with the fastening portion 420 to fasten the auxiliary positioning plate 300 to the worktable 100.

Please refer to fig. 6, fig. 6 is a schematic structural diagram of the positioning clip; the positioning clip 410 includes a base portion 411, a pressing portion 412, a hinge portion 413, and an engaging portion 414; the pressing portion 412 and the engaging portion 414 are respectively disposed at two ends of the base portion 411, the hinge portion 413 is located at a middle portion of the base portion 411, the hinge portion 413 and the engaging portion 414 both extend toward one side of the table 100, and the hinge portion 413 is rotatably connected to the auxiliary positioning plate 300 through a pin 430. Further, a return spring (not shown) may be further disposed outside the pin 430, and the return spring is configured to elastically return the positioning clip 410 when the positioning clip 410 is engaged with and disengaged from the engaging portion 420.

Optionally, a first connecting plate 301 and a second connecting plate 302 are respectively disposed on two opposite sides of the auxiliary positioning plate 300; the number of the positioning clips 410 is two, and the two positioning clips are respectively rotatably connected with the first connecting plate 301 and the second connecting plate 302; the first connecting plate 301 and the second connecting plate 302 are both extended towards a direction perpendicular to the auxiliary positioning plate 300; a first engaging portion 421 and a second engaging portion 422 (please refer to fig. 2) are respectively disposed on two opposite sides of the working platform 100 and are engaged with the positioning clip 410.

A first mounting groove 3011 is formed in one side of the first connecting plate 301 facing away from the workbench 100, the hinge portion 413 of the positioning clip 410 is inserted into the first mounting groove 3011, and two ends of the pin shaft 430 are respectively inserted into two opposite sides of the first mounting groove 3011; a second mounting groove 3021 is formed in one side of the second connecting plate 302 facing away from the workbench 100, a hinge portion 413 of the other positioning clip 410 is inserted into the second mounting groove 3021, and two ends of a pin 430 are respectively inserted into two opposite sides of the second mounting groove 3021. It should be noted that the terms "first", "second" and "third" in the present invention are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of the feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

Referring to fig. 5, the first engaging portion 421 (the second engaging portion 422 and the first engaging portion 421 are similar in structure and symmetrically disposed on two opposite sides of the worktable 100) is further provided with a first engaging groove 4211, and the first engaging groove 4211 is provided with a first engaging pin 4212; the engaging portion 414 of the positioning clip 410 is engaged with the first engaging pin 4212 to realize a engaging connection.

Referring to fig. 2, 7, 8 and 9, fig. 7 is a schematic structural view of the bottom mold plate and the limiting assembly, and fig. 8 is an enlarged schematic structural view of a position B in fig. 7; FIG. 9 is a schematic diagram of FIG. 8 with the structure broken away; the fixture in the embodiment of the present application further includes a plurality of limiting assemblies 500, the limiting assemblies 500 are circumferentially disposed along the side wall of the profiling groove 210 of the bottom mold plate 200, and the limiting assemblies 500 are used for limiting the position of the semi-finished electronic device of the housing to be assembled in the profiling groove 210. The limiting assembly 500 comprises an abutting unit 510 and a pressing unit 520, wherein the abutting unit 510 is clamped on the side wall of the profiling groove 210 of the bottom template 200, and the pressing unit 520 is used for pressing the abutting unit 510 to be fixed on the bottom template 200. The bottom of the profiling groove 210 of the bottom template 200 is provided with a plurality of avoiding grooves 211.

Further, please refer to fig. 10 and 11 together, fig. 10 is a schematic structural diagram of the abutting unit in fig. 9; FIG. 11 is a schematic view of a portion of the bottom form of FIG. 7; the abutting unit 510 includes a main body 511, an abutting portion 512, and a positioning portion 513, which are integrally formed. The abutting portion 512 extends toward the contour groove 210 of the bottom mold plate 200 (i.e., in the X direction in the drawing) and protrudes from the side wall of the contour groove 210; the positioning part 513 extends toward the top surface of the base plate 200 where the profile groove 210 is provided (i.e., the Z direction in the drawing); the bottom template 200 is provided with a T-shaped groove 220, and the main body portion 511 and part of the abutting portion 512 of the abutting unit 510 are structurally arranged in the T-shaped groove 220; the pressing unit 520 comprises a positioning hole 521 and a connecting hole 522, the positioning portion 513 of the abutting unit 510 is inserted into the positioning hole 521 to position the abutting unit 510 by the pressing unit 520 in the X-Y plane, and the connecting hole 522 is used for fixedly connecting the pressing unit 520 with the bottom form 200; specifically, the pressing unit 520 and the bottom mold plate 200 may be fixedly connected by inserting a screw (not shown) into the connecting hole 522, so as to fix the pressing unit 520 to the bottom mold plate 200.

Optionally, with continued reference to fig. 10 and 11, the abutting unit 510 further includes a guiding portion 514; the guiding portion 514 is integrally connected to the abutting portion 512, the guiding portion 514 extends in a direction away from the bottom of the contour groove 210 (i.e. in the Z direction in the figure), the guiding portion 514 is provided with a guiding inclined surface 5141, and the guiding inclined surface 5141 is smoothly transitionally connected to the abutting surface 5121 of the abutting portion 512. The guiding inclined plane 5141 is open towards the outer side of the bottom mold plate 200, and functions to enable the semi-finished electronic device of the housing to be assembled to slide into the contour groove 210 along the guiding inclined plane 5141 when the semi-finished electronic device 55 of the housing to be assembled (please refer to fig. 2) is installed, and when contacting the bottom of the contour groove 210, the semi-finished electronic device of the housing to be assembled is abutted against and matched with the abutting surface 5121 of the abutting portion 512, so that the abutting portion 512 abuts against and positions the semi-finished electronic device 55 of the housing to be assembled in the X-Y plane.

With reference to fig. 10, the abutting unit 510 further includes a spacer portion 515, the spacer portion 515 and the abutting portion 512 are integrally connected, the spacer portion 515 and the main body portion 511 are respectively located at two opposite sides of the abutting portion 515, the spacer portion 515 abuts against the bottom of the dummy groove 210, and is used for spacing the bottom of the dummy groove 210 and the semi-finished electronic device 55 of the housing to be assembled, so as to prevent the semi-finished electronic device 55 of the housing to be assembled and the bottom of the dummy groove 210 from being directly contacted to scratch. It should be noted that all the directional indicators (such as upper, lower, left, right, front and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

Alternatively, the abutting unit 510 may be made of rubber; mainly utilizes the elasticity and durability of rubber, the material of the pressing unit 520 may be a metal sheet or a hard resin sheet, and the pressing unit 520 mainly plays a role in pressing and fixing the abutting unit 510. Wherein, spacing subassembly 500 in this application embodiment adopts two parts of detachable (butt unit 510 and pressfitting unit 520) to constitute, when butt unit 510 warp or damage because of wearing and tearing, can in time change, has avoided leading to the condition emergence of the whole die block board of needs change when local structure wearing and tearing appear because the form of design and the integrative structure of die block board.

Referring to fig. 7, the bottom mold plate 200 is further provided with avoiding grooves 230, and the avoiding grooves 230 are disposed on two opposite sides of the contour groove 210 and are communicated with the contour groove 210. The avoiding groove 230 is used for avoiding (hands of operators or manipulators) when the semi-finished electronic equipment of the shell to be assembled is placed or taken out from the profiling groove 210, so that the semi-finished electronic equipment of the shell to be assembled can be conveniently taken and placed.

Referring to fig. 2, 12 and 13 together, fig. 12 is a schematic view illustrating a structure of the auxiliary positioning plate and the auxiliary guiding unit, and fig. 13 is an enlarged view illustrating a portion of the structure at C in fig. 12; the jig in the embodiment of the present application further includes a plurality of auxiliary guide units 600, wherein the plurality of auxiliary guide units 600 are circumferentially disposed along a sidewall of the positioning groove 310 of the auxiliary positioning plate 300; referring to fig. 14, fig. 14 is a schematic structural view of the auxiliary guide unit in fig. 13; the auxiliary guide units 600 each include a body part 610 and a guide part 620 of an integrated structure; the body portion 610 is used for connecting with the auxiliary positioning plate 300.

Optionally, the auxiliary positioning plate 300 is connected to a mounting groove 330, the body 610 is disposed in the mounting groove 330, and the body 610 may further be provided with a mounting hole 611, so that the body 610 is fixed in the mounting groove 330 by a screw or the like. The guiding portion 620 is inclined downward and extends toward the contour groove 210 of the bottom mold plate 200, for guiding the housing to be assembled in the positioning groove 310 onto the semi-finished electronic device 55 (please refer to fig. 2) of the housing to be assembled in the contour groove 210 of the bottom mold plate 200. The auxiliary guide unit 600 may be made of an integral rubber material.

The operation process of the clamp for assisting the electronic equipment shell assembly in the embodiment is as follows: firstly, semi-finished electronic equipment of a shell to be assembled is placed in a contour groove of a bottom template, then an auxiliary positioning plate is covered (aligned by using a positioning column and locked by a connecting mechanism), the shell (a battery cover) to be assembled is placed in a positioning groove of the auxiliary positioning plate, the battery cover is pressed until the battery cover is aligned, clamped and matched with the semi-finished electronic equipment of the shell to be assembled, then the auxiliary positioning plate is opened, and finally the assembled electronic equipment is taken out from the contour groove of the bottom template.

The above description is only a part of the embodiments of the present invention, and not intended to limit the scope of the present invention, and all equivalent devices or equivalent processes performed by the present invention through the contents of the specification and the drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A fixture for assisting in the assembly of an electronic device housing, the fixture comprising:

the workbench is provided with a bearing surface;

2. The fixture according to claim 1, wherein the carrying surface of the worktable is provided with positioning posts, and the auxiliary positioning plate is provided with positioning holes for cooperating with the positioning posts to realize the positioning slots of the auxiliary positioning plate and the contour grooves of the bottom mold plate being arranged oppositely.

3. The clamp of claim 1, wherein the connecting mechanism comprises a positioning clip rotatably connected to the auxiliary positioning plate and a fastening portion fixedly disposed on the worktable, and the positioning clip is engaged with the fastening portion to fasten the auxiliary positioning plate and the worktable.

4. The clip of claim 3 wherein the alignment clip comprises a base portion, a pressing portion, a hinge portion, and a snap portion of unitary construction; the pressing part and the buckling part are respectively arranged at two ends of the base part, the hinge part is positioned in the middle of the base part, the hinge part and the buckling part both extend towards one side of the workbench, and the hinge part is rotatably connected with the auxiliary positioning plate through a pin shaft.

5. The clamp of claim 4, wherein the auxiliary positioning plate is provided with a first connecting plate and a second connecting plate at two opposite sides thereof; the two positioning clamps are respectively and rotatably connected with the first connecting plate and the second connecting plate; and a first clamping part and a second clamping part which are matched with the positioning clamp are respectively arranged on two opposite sides of the workbench.

6. The clamp according to claim 5, wherein a first mounting groove is formed in one side of the first connecting plate facing away from the workbench, the hinge portion of the positioning clip is inserted into the first mounting groove, and two ends of the pin shaft are respectively inserted into two opposite sides of the first mounting groove; the second connecting plate is provided with a second mounting groove on one side departing from the workbench, the other hinge part of the positioning clamp is inserted in the second mounting groove, and two ends of the pin shaft are respectively inserted in two opposite sides of the second mounting groove.

7. The fixture according to claim 1, further comprising a plurality of position limiting assemblies circumferentially disposed along the sidewalls of the contoured groove of the bottom mold plate for limiting the position of a semi-finished electronic device of a housing to be assembled within the contoured groove.

8. The fixture according to claim 7, wherein the position-limiting assembly comprises an abutting unit and a pressing unit, the abutting unit is clamped on the side wall of the profiling groove of the bottom template, and the pressing unit is used for pressing the abutting unit to be fixed on the bottom template.

9. The cleaning apparatus according to claim 8, wherein the abutting unit includes a main body portion, an abutting portion, and a positioning portion of an integral structure, the abutting portion extending toward the profile groove and protruding from a side wall of the profile groove; the positioning part extends towards the direction of the top surface of the profile groove bottom template provided with the profile groove; the bottom template is provided with a T-shaped groove, and the main body part and part of the abutting part structure are arranged in the T-shaped groove; the pressing unit comprises a positioning hole and a connecting hole, the positioning part of the abutting unit is inserted into the positioning hole to position the abutting unit, and the connecting hole is used for fixedly connecting the pressing unit and the bottom template.

10. The cleaning apparatus as claimed in claim 9, wherein the abutting unit further comprises a guide portion integrally connected with the abutting portion, the guide portion extending in a direction away from the bottom of the profiling groove, the guide portion being provided with a guide slope smoothly transitionally connected with the abutting surface of the abutting portion.

11. The cleaning device as claimed in claim 10, wherein the abutting unit further comprises a spacer portion, the spacer portion and the abutting portion are integrally connected, the spacer portion and the main body portion are respectively located on two opposite sides of the abutting portion, and the spacer portion abuts against the bottom of the dummy groove and is used for spacing the bottom of the dummy groove from a semi-finished electronic device of the housing to be assembled.

12. The cleaning apparatus according to claim 8, wherein the abutting unit is made of rubber; the material of the pressing unit is a metal sheet or a hard resin sheet.

13. The jig of claim 1, further comprising a plurality of auxiliary guide units circumferentially disposed along a sidewall of the auxiliary positioning plate positioning slot; each auxiliary guide unit comprises a body part and a guide part which are of an integral structure; the main body part is used for being connected with the auxiliary positioning plate, and the guide part extends towards the profiling groove of the bottom template and is used for guiding the shell to be assembled in the positioning groove to the semi-finished electronic equipment of the shell to be assembled in the profiling groove of the bottom template.

14. The clamp according to claim 1, wherein the bottom form plate is further provided with avoidance grooves, and the avoidance grooves are formed on two opposite sides of the contour groove and are communicated with the contour groove.