CN119819816A - Thermoforming process - Google Patents

Abstract

The invention discloses a thermoforming process which comprises the following steps of S1, counting part design data and final modeling data of parts produced by the same part modeling and manufacturing process parameters, setting shrinkage and manufacturing tolerance size, S2, modifying initial tolerance size of parts to be machined to obtain final tolerance size, S3, modifying initial part data of the parts to be machined to obtain final part data, S4, designing a tolerance band, S5, stamping and blanking blanks based on the tolerance band to obtain the parts to be machined, and S6, feeding the parts to be machined into a thermoforming die through a feeding device to obtain stamping parts. The invention can ensure that the tolerance of the part to be processed after stamping blanking is within the tolerance zone, ensures the flow stability of the part to be processed in the thermoforming process, ensures that the tolerance of the stamping part obtained after thermoforming processing does not exceed the tolerance zone, and further does not need to cut the edge of the stamping part, thereby reducing the production cost.

Description

Thermoforming process

Technical Field

The invention relates to the technical field of thermoforming. More particularly, the present invention relates to a thermoforming process.

Background

At present, a common hot-formed part in the automobile industry needs to be subjected to cold stamping and trimming after hot stamping, and then redundant waste materials are cut off, but the strength of the hot-stamped part after quenching is up to 1350Mpa-1500Mpa, if the hot-stamped part is subjected to cold stamping and trimming later, the trimming knife edge of a die is extremely severely worn, maintenance is needed after stamping for one shift, a large number of spare parts are needed, and the part with weak trimming knife edge often has tipping. The requirement of the high-strength plate on the blanking force of the press is higher, the complex part also needs a plurality of working procedures to finish the trimming of the part, the cost is higher, the burrs of the product are larger, and the cost is higher if the laser cutting is performed.

Therefore, there is a need to provide a thermoforming process to eliminate trimming of thermoformed parts, thereby reducing part production costs.

Disclosure of Invention

It is still another object of the present invention to provide a thermoforming process that eliminates the need for edge cutting of the stamping and reduces manufacturing costs.

To achieve these objects and other advantages and in accordance with the purpose of the invention, there is provided a thermoforming process comprising the steps of:

S1, counting part design data and final modeling data of a part produced by the same part modeling and manufacturing process parameters;

S2, acquiring an initial tolerance size of the part to be processed, and modifying the initial tolerance size based on the manufacturing tolerance size to obtain a final tolerance size;

S3, acquiring initial part data of the part to be processed, and modifying the initial part data based on the designed shrinkage and the final tolerance size to obtain final part data;

S4, designing a tolerance zone based on the final tolerance dimension, the final part data and the set shrinkage;

S5, stamping and blanking the blank based on a tolerance zone to obtain a part to be processed, wherein positioning holes are stamped and arranged at two ends of the part to be processed in the stamping and blanking process;

S6, conveying the part to be processed into a thermal forming die through a feeding device for stamping processing, and obtaining a stamping part.

Preferably, the thermoforming mold comprises:

The upper base and the lower base are oppositely arranged, the upper base and the lower base are connected into a whole through a guide column, an upper template is connected to the guide column in a sliding manner, the upper template is positioned between the upper base and the lower base, an upper shear die is arranged on the bottom surface of the upper template, and a stretching head is accommodated in an inner cavity of the upper shear die;

The fixed end of the hydraulic oil cylinder is fixed on the top surface of the upper base, the free end of the hydraulic oil cylinder vertically penetrates out of the bottom surface of the upper base downwards and is connected with the fixed end of the air cylinder, the fixed end of the air cylinder is fixedly arranged on the top surface of the upper template, and the free end of the air cylinder penetrates through the bottom surface of the upper template and is connected with the stretching head;

The lower shear die is arranged on the top surface of the lower base, and a forming die is arranged in the lower shear die;

In S6, during stamping, the feeding device feeds the part to be machined to the top surface of the lower shear die, the free end of the hydraulic oil cylinder is driven to extend, the upper die plate is driven by the hydraulic oil cylinder to slide downwards to the upper shear die and the lower shear die to be clamped, the part to be machined is pressed on the top surface of the upper shear die, the free end of the cylinder is driven to extend to drive the stretching head to move downwards, and the stretching head is matched with the forming die to stamp the part to be machined.

Preferably, the thermal forming die is provided with a limiting piece, and the part to be processed is fixed on the limiting piece through the positioning hole and then is located in a stamping area of the thermal forming die.

Preferably, the limiting parts comprise a plurality of first limiting parts arranged on the top surface of the lower shear die and a plurality of second limiting parts arranged on the bottom surface of the upper shear die, and the first limiting parts, the second limiting parts and the positioning holes on the material sheet are arranged in a one-to-one correspondence manner;

The first limiting piece includes:

The arc-shaped groove is formed in the top surface of the lower shear die, a limit column is arranged in the arc-shaped groove, a spring is fixedly connected between the limit column and the inner bottom surface of the arc-shaped groove, a positioning column is arranged at the top of the limit column, the diameter size of the limit column is larger than that of the positioning hole, the diameter size of the positioning column is smaller than that of the positioning hole, and the top surface of the limit column extends out of the top surface of the lower shear die;

the second limiting piece is a limiting groove formed in the bottom surface of the upper shear die;

During stamping, a part to be machined is limited in a stamping area of a thermoforming mold through a positioning column, an upper shearing mold is driven by a hydraulic oil cylinder to downwards move to a limit groove on the upper shearing mold and is spliced with the positioning column, then pressure is applied to the limit column, the limit column downwards compresses a spring until the top surface of the limit column and the top surface of the upper shearing mold are located in the same horizontal plane, and the upper shearing mold and the lower shearing mold are assembled.

Preferably, the inner side wall of the arc-shaped groove is not in contact with the limit post, a first vent hole is formed in the lower shear die and is communicated with the arc-shaped groove and the outer part of the lower shear die, a second vent hole is formed in the upper shear die and is communicated with the limit groove and the inner cavity of the upper shear die, the diameter size of the limit groove is larger than that of the positioning post and the limit post, and an air passage communicated with the arc-shaped groove and the limit groove is formed in the limit post.

Preferably, a plurality of limiting plates are arranged at intervals on the periphery of the limiting column, one end of any limiting plate is hinged with the outer side wall of the top surface of the limiting column, and the other end of any limiting plate is abutted with the inner side wall of the arc-shaped groove;

During punching, the limiting columns compress the springs downwards to drive the limiting plates to slide to a horizontal state along the inner walls of the arc grooves, and the top surfaces of the limiting plates and the top surfaces of the upper shearing dies are located on the same horizontal plane.

The invention has the advantages that the design tolerance zone is designed after the related data of the part to be processed is analyzed, modified and determined before the thermoforming process, and the tolerance zone is controllable, so that the stamping blanking is performed based on the tolerance zone, the tolerance of the part to be processed after the stamping blanking is ensured to be within the tolerance zone, the tolerance is controllable, the positioning hole is stamped on the part to be processed during the stamping blanking, the positioning hole is used for giving the part to be processed a shrink allowance during the thermoforming, the part to be processed is shrunk or expanded within the range of the positioning hole, meanwhile, the tolerance zone can also ensure that the part to be processed has enough shrink allowance during the thermoforming process, the stability of the flow of the part to be processed is ensured, and finally, the tolerance of the stamping part obtained after the thermoforming does not exceed the tolerance zone range, thereby avoiding the edge line cutting of the stamping part and reducing the production cost.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Drawings

FIG. 1 is a schematic front view of a thermal forming die in which an upper die and a lower die are separated from each other;

Fig. 2 is a schematic front view of the upper and lower shear molds in the above embodiment;

FIG. 3 is an enlarged schematic view of the structure of FIG. 2A;

description of the specification reference numerals:

1. The upper base, 2, the lower base, 3, the guide post, 4, the upper template, 5, the upper shear die, 6, the stretching head, 7, the hydraulic cylinder, 8, the cylinder, 9, the lower shear die, 10, the forming die, 11, the arc groove, 12, the spacing post, 13, the spring, 14, the reference column, 15, the spacing groove, 16, the limiting plate, 17, the first vent, 18, the second vent, 19, the upper shear die inner chamber.

Detailed Description

The present invention is described in further detail below with reference to the drawings to enable those skilled in the art to practice the invention by referring to the description.

It should be noted that, in the description of the present invention, the terms "transverse", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.

As shown in fig. 1-3, the present invention provides a thermoforming process comprising the steps of:

S1, counting part design data and final modeling data of a part produced by the same part modeling and manufacturing process parameters;

S2, acquiring an initial tolerance size of the part to be processed, and modifying the initial tolerance size based on the manufacturing tolerance size to obtain a final tolerance size;

S3, acquiring initial part data of the part to be processed, and modifying the initial part data based on the designed shrinkage and the final tolerance size to obtain final part data;

S4, designing a tolerance zone based on the final tolerance dimension, the final part data and the set shrinkage;

S5, stamping and blanking the blank based on a tolerance zone to obtain a part to be processed, wherein positioning holes are stamped and arranged at two ends of the part to be processed in the stamping and blanking process;

S6, conveying the part to be processed into a thermal forming die through a feeding device for stamping processing, and obtaining a stamping part.

In the technical scheme, the thermoforming process is suitable for bi-directional stamping stretching of the part to be processed, part design data and final modeling data are firstly obtained according to the produced part, the data are analyzed, shrinkage of the part to be processed due to thermoforming shrinkage in thermoforming processing and manufacturing tolerance size generated in process manufacturing are set, the initial tolerance size of the part to be processed is modified based on the manufacturing tolerance size, so that the tolerance size of the part to be processed is matched with the current manufacturing process, the initial part data of the part to be processed is modified according to the final tolerance size and shrinkage obtained by modification, the final part data are the part data of the part to be processed after the completion of the processing, and the tolerance zone is designed based on the preset final part data, the final tolerance size and the shrinkage, and the tolerance zone is controllable due to the fact that the tolerance zone is used for stamping blanking, the tolerance zone is guaranteed, the tolerance zone is controllable, and the positioning hole is used for giving the part to be processed when thermoforming, so that the tolerance zone is enabled to shrink, the part to be processed is enabled to be in the range of the positioning hole, and the tolerance zone is enabled to shrink, and the tolerance zone is also enabled to be expanded in the range of the tolerance zone is guaranteed, and the tolerance zone is also enabled to be free of the tolerance zone is guaranteed, and the tolerance zone is not required to be expanded, and the production line is enabled to be required to be cut, and the tolerance zone is enabled to be stable after the thermal forming process is enabled.

In another aspect, as shown in fig. 1 and 2, the thermoforming mold includes:

The upper base 1 and the lower base 2 are oppositely arranged, the upper base 1 and the lower base 2 are connected into a whole through a guide post 3, an upper die plate 4 is connected to the guide post 3 in a sliding manner, the upper die plate 4 is positioned between the upper base 1 and the lower base 2, an upper shear die 5 is arranged on the bottom surface of the upper die plate 4, and a stretching head 6 is accommodated in an inner cavity 19 of the upper shear die;

The fixed end of the hydraulic oil cylinder 7 is fixed on the top surface of the upper base 1, the free end of the hydraulic oil cylinder vertically penetrates out of the bottom surface of the upper base 1 downwards and is connected with the fixed end of the air cylinder 8, the fixed end of the air cylinder 8 is fixedly arranged on the top surface of the upper template 4, and the free end of the air cylinder 8 penetrates through the bottom surface of the upper template 4 and is connected with the stretching head 6;

a lower shear die 9 disposed on the top surface of the lower base 2, wherein a forming die 10 is disposed inside the lower shear die 9;

In S6, during stamping, the feeding device feeds the part to be machined to the top surface of the lower shear die 9, the free end of the hydraulic oil cylinder 7 is driven to stretch, the upper die plate 4 slides downwards to the upper shear die 5 to be clamped with the lower shear die 9 under the driving of the hydraulic oil cylinder 7, the part to be machined is pressed on the top surface of the upper shear die 5, the free end of the air cylinder 8 is driven to stretch to drive the stretching head 6 to move downwards, and the part to be machined is matched with the forming die 10 to be stamped.

In another technical scheme, a limiting piece is arranged on the thermoforming die, and the part to be processed is fixed on the limiting piece through the positioning hole and then located in a stamping area of the thermoforming die.

In the technical scheme, the part to be processed is limited in the stamping area through the limiting piece during thermoforming processing, so that the shrinkage stability of the part to be processed in the thermoforming process can be ensured, and the flowing stability of the part to be processed is further ensured.

In another technical scheme, the limiting pieces comprise a plurality of first limiting pieces arranged on the top surface of the lower shear die 9, a plurality of second limiting pieces arranged on the bottom surface of the upper shear die 5, and a plurality of first limiting pieces, a plurality of second limiting pieces and a plurality of positioning holes on the material sheet are arranged in a one-to-one correspondence manner;

The first limiting piece includes:

The arc-shaped groove 11 is formed in the top surface of the lower shear die 9, a limit post 12 is arranged in the arc-shaped groove 11, a spring 13 is fixedly connected between the limit post 12 and the inner bottom surface of the arc-shaped groove 11, a positioning post 14 is arranged at the top of the limit post 12, the diameter size of the limit post 12 is larger than that of the positioning hole, the diameter size of the positioning post 14 is smaller than that of the positioning hole, and the top surface of the limit post 12 extends out of the top surface of the lower shear die 9;

the second limiting piece is a limiting groove 15 formed in the bottom surface of the upper shear die 5;

During punching, the part to be processed is limited in a punching area of the thermoforming die through the positioning column 14, the upper shearing die 5 is driven by the hydraulic oil cylinder 7 to move downwards to a limit groove 15 on the upper shearing die and is spliced with the positioning column 14, then pressure is applied to the limit column 12, the limit column 12 compresses the spring 13 downwards until the top surface of the limit column 12 and the top surface of the upper shearing die 5 are located in the same horizontal plane, and the upper shearing die 5 and the lower shearing die 9 are clamped.

In the technical scheme, as shown in fig. 3, an arc-shaped groove 11 is used for accommodating a limit column 12 and a spring 13, a positioning column 14 is used for being connected with a positioning hole on a part to be processed, in an initial state, an upper shear die 5 and a lower shear die 9 are mutually separated, the top surface of the limit column 12 extends out of the top surface of the lower shear die 9, during punching, the positioning hole on the part to be processed is firstly penetrated on the positioning column 14, the part to be processed is limited in a punching area through the positioning column 14, then a hydraulic cylinder 7 is driven to drive the upper shear die 5 to move downwards to a position where the limit groove 15 is spliced with the positioning column 14, the extrusion spring 13 is continuously moved downwards to drive the limit column 12 to move downwards to be positioned on the same horizontal plane with the top surface of the upper shear die 5, at this time, the upper shear die 5 and the lower shear die 9 are clamped, a stretching head 6 is driven to move downwards to punch the part to be processed, after punching is completed, the upper shear die 5 is driven to be separated from the lower shear die 9, and the spring 13 is reset to eject the limit column 12 out of the top surface of the lower shear die 9, so that a stamping part positioned on the positioning column 14 is ejected and prevented from being clamped in a forming die 10; the size of the positioning column 14 is smaller than that of the positioning hole, and the positioning hole can provide enough shrinkage allowance for the part to be processed while realizing the positioning function of the part to be processed, so that the part to be processed moves in a small range, and the shrinkage stability and the flow stability are ensured.

In another technical scheme, the inner side wall of the arc-shaped groove 11 is not in contact with the limit post 12, a first vent hole 17 is formed in the lower shear die 9, the first vent hole 17 is communicated with the outer parts of the arc-shaped groove 11 and the lower shear die 9, a second vent hole 18 is formed in the upper shear die 5, the second vent hole 18 is communicated with the limit groove 15 and the inner cavity 19 of the upper shear die, the diameter size of the limit groove 15 is larger than the diameter sizes of the positioning post 14 and the limit post 12, and an air passage communicated with the arc-shaped groove 11 and the limit groove 15 is formed in the limit post 12.

In the technical scheme, after the upper shear die 5 and the lower shear die 9 are clamped, air in the forming die 10 is difficult to discharge, when the stretching head 6 moves downwards to press a part to be processed, the surface of a formed stamping part is easy to generate quality problems such as air holes due to the influence of compressed air, therefore, as shown in fig. 3, the application is provided with the second air holes 18 on the upper shear die 5, the first air holes 17 on the lower shear die 9, the limit posts 12 are provided with the air passages communicated with the arc grooves 11 and the limit slots 15, wherein the air passages are communicated with the arc grooves 11 through the gaps between the limit posts 14 and the limit holes, when the upper shear die 5 and the lower shear die 9 are clamped, the stretching head 6 moves downwards, the air in the forming die 10 can be extruded, and then the air can enter the inner cavity 19 of the upper shear die from the gaps between the forming die 10 and the stretching head 6, and then sequentially pass through the second air holes 18, the gaps between the limit slots 15 and the limit posts 14, the gaps between the limit posts 14 and the limit posts 12, the air passages, the diameter of the arc grooves 11 and the limit posts 12, the first air holes 17, and the air passages 17, after the forming the surface quality problems are avoided.

In another technical scheme, a plurality of limiting plates 16 are arranged at intervals on the periphery of the limiting post 12, one end of any limiting plate 16 is hinged with the outer side wall of the top surface of the limiting post 12, and the other end of the limiting plate is abutted with the inner side wall of the arc-shaped groove 11;

During punching, the limiting post 12 compresses the spring 13 downwards to drive the limiting plate 16 to slide to a horizontal state along the inner wall of the arc-shaped groove 12, and the top surface of the limiting plate 16 and the top surface of the upper shear die 5 are located on the same horizontal plane.

In the technical scheme, during stamping, the die clamping speed of the upper shearing die 5 and the lower shearing die 9 is high, the limiting column 12 is arranged in the arc-shaped groove 11 through the spring 13, the limiting column 12 is not in contact with the inner wall of the arc-shaped groove 11, and the limiting column 12 is easy to shift in the process of compressing the spring 13 under the impact of high speed and high pressure, so that the limiting plates 16 are arranged at intervals on the periphery of the limiting column 12, and the limiting plates 16 are used for carrying out the functions of vertical guiding and transverse limiting on the limiting column 12, so that the limiting column 12 vertically compresses the spring 13 in the stamping process.

Although embodiments of the present invention have been disclosed above, it is not limited to the details and embodiments shown and described, it is well suited to various fields of use for which the invention would be readily apparent to those skilled in the art, and accordingly, the invention is not limited to the specific details and illustrations shown and described herein, without departing from the general concepts defined in the claims and their equivalents.

Claims (6)

1. A thermoforming process comprising the steps of:

S1, counting part design data and final modeling data of a part produced by the same part modeling and manufacturing process parameters;

S2, acquiring an initial tolerance size of the part to be processed, and modifying the initial tolerance size based on the manufacturing tolerance size to obtain a final tolerance size;

S3, acquiring initial part data of the part to be processed, and modifying the initial part data based on the designed shrinkage and the final tolerance size to obtain final part data;

S4, designing a tolerance zone based on the final tolerance dimension, the final part data and the set shrinkage;

S5, stamping and blanking the blank based on a tolerance zone to obtain a part to be processed, wherein positioning holes are stamped and arranged at two ends of the part to be processed in the stamping and blanking process;

S6, conveying the part to be processed into a thermal forming die through a feeding device for stamping processing, and obtaining a stamping part.

2. The thermoforming process as claimed in claim 1, wherein the thermoforming mould comprises:

The upper base and the lower base are oppositely arranged, the upper base and the lower base are connected into a whole through a guide column, an upper template is connected to the guide column in a sliding manner, the upper template is positioned between the upper base and the lower base, an upper shear die is arranged on the bottom surface of the upper template, and a stretching head is accommodated in an inner cavity of the upper shear die;

The fixed end of the hydraulic oil cylinder is fixed on the top surface of the upper base, the free end of the hydraulic oil cylinder vertically penetrates out of the bottom surface of the upper base downwards and is connected with the fixed end of the air cylinder, the fixed end of the air cylinder is fixedly arranged on the top surface of the upper template, and the free end of the air cylinder penetrates through the bottom surface of the upper template and is connected with the stretching head;

The lower shear die is arranged on the top surface of the lower base, and a forming die is arranged in the lower shear die;

In S6, during stamping, the feeding device feeds the part to be machined to the top surface of the lower shear die, the free end of the hydraulic oil cylinder is driven to extend, the upper die plate is driven by the hydraulic oil cylinder to slide downwards to the upper shear die and the lower shear die to be clamped, the part to be machined is pressed on the top surface of the upper shear die, the free end of the cylinder is driven to extend to drive the stretching head to move downwards, and the stretching head is matched with the forming die to stamp the part to be machined.

3. The thermoforming process according to claim 2, wherein the thermoforming mold is provided with a limiting member, and the part to be processed is located in a stamping area of the thermoforming mold after being fixed on the limiting member through the positioning hole.

4. The thermoforming process of claim 3, wherein the limiting members comprise a plurality of first limiting members arranged on the top surface of the lower shear die, and a plurality of second limiting members arranged on the bottom surface of the upper shear die, wherein the plurality of first limiting members, the plurality of second limiting members and the plurality of positioning holes in the material sheet are arranged in a one-to-one correspondence;

The first limiting piece includes:

The arc-shaped groove is formed in the top surface of the lower shear die, a limit column is arranged in the arc-shaped groove, a spring is fixedly connected between the limit column and the inner bottom surface of the arc-shaped groove, a positioning column is arranged at the top of the limit column, the diameter size of the limit column is larger than that of the positioning hole, the diameter size of the positioning column is smaller than that of the positioning hole, and the top surface of the limit column extends out of the top surface of the lower shear die;

the second limiting piece is a limiting groove formed in the bottom surface of the upper shear die;

During stamping, a part to be machined is limited in a stamping area of a thermoforming mold through a positioning column, an upper shearing mold is driven by a hydraulic oil cylinder to downwards move to a limit groove on the upper shearing mold and is spliced with the positioning column, then pressure is applied to the limit column, the limit column downwards compresses a spring until the top surface of the limit column and the top surface of the upper shearing mold are located in the same horizontal plane, and the upper shearing mold and the lower shearing mold are assembled.

5. The thermoforming process of claim 4, wherein the inner side wall of the arc-shaped groove is not in contact with the limit post, the lower shear die is provided with a first vent hole, the first vent hole is communicated with the arc-shaped groove and the outer part of the lower shear die, the upper shear die is provided with a second vent hole, the second vent hole is communicated with the limit groove and the inner cavity of the upper shear die, the diameter size of the limit groove is larger than the diameter sizes of the positioning post and the limit post, and the limit post is provided with an air passage communicated with the arc-shaped groove and the limit groove.

6. The thermoforming process of claim 4, wherein a plurality of limiting plates are arranged on the periphery of the limiting post at intervals, one end of any limiting plate is hinged with the outer side wall of the top surface of the limiting post, and the other end of the limiting plate is abutted with the inner side wall of the arc-shaped groove;

During punching, the limiting columns compress the springs downwards to drive the limiting plates to slide to a horizontal state along the inner walls of the arc grooves, and the top surfaces of the limiting plates and the top surfaces of the upper shearing dies are located on the same horizontal plane.