CN113715308B - Adjustable multi-point progressive flanging forming device and method - Google Patents

Adjustable multi-point progressive flanging forming device and method Download PDF

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Publication number
CN113715308B
CN113715308B CN202111024449.8A CN202111024449A CN113715308B CN 113715308 B CN113715308 B CN 113715308B CN 202111024449 A CN202111024449 A CN 202111024449A CN 113715308 B CN113715308 B CN 113715308B
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adjusting rod
piece
flanging
adjustable multi
forming device
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CN113715308A (en
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赵亦希
程旋
万李
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Shanghai Jiaotong University
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Shanghai Jiaotong University
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D31/00Other methods for working sheet metal, metal tubes, metal profiles
    • B21D31/005Incremental shaping or bending, e.g. stepwise moving a shaping tool along the surface of the workpiece
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D19/00Flanging or other edge treatment, e.g. of tubes
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00Computer-aided design [CAD]
    • G06F30/20Design optimisation, verification or simulation
    • G06F30/23Design optimisation, verification or simulation using finite element methods [FEM] or finite difference methods [FDM]
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F2119/00Details relating to the type or aim of the analysis or the optimisation
    • G06F2119/18Manufacturability analysis or optimisation for manufacturability

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Evolutionary Computation (AREA)
  • Geometry (AREA)
  • General Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Bending Of Plates, Rods, And Pipes (AREA)

Abstract

An adjustable multi-point progressive flanging forming device and method comprises the following steps: hold-down mechanism, flexible bullet pad subassembly and a plurality of range upon range of regulating lever subassembly that from top to bottom set gradually and be used for the six degrees of freedom work ends that take shape, wherein: one end of the piece to be formed is arranged between the pressing mechanism and the flexible elastic cushion assembly, the flexible elastic cushion assembly envelopes the outer surface formed by one side of the stacked adjusting rod assembly, and the six-degree-of-freedom working end is positioned on the outer side of the piece to be formed to bend and deform the piece. The invention changes the change of the curvature of the die surface by adjusting the extension and retraction of the adjusting rod component until the shape of the preset curved surface of the piece to be formed; the adjusting rod assemblies are cooperatively controlled, so that the change of curvatures of different die surfaces is realized, and the flanging forming of materials with different sizes by the same platform is realized.

Description

Adjustable multi-point progressive flanging forming device and method
Technical Field
The invention relates to a technology in the field of sheet metal part manufacturing, in particular to an adjustable multi-point progressive flanging forming device and method.
Background
The existing flanging part production mainly has two forming modes of manual hammering and die flanging fixing. The flanging type part can rebound in the forming process, the efficiency of adjusting the rebound amount by manual hammering is low, the labor intensity of workers is high, and the environmental noise is high; the flanging forming by adopting the fixed die needs to design corresponding dies aiming at different products, so that the utilization rate of the die is low, the development cost is high, and the production period is long; and the resilience of the flanging can not be adjusted and compensated under the condition that the die is fixed, the stress is uneven, and the forming precision is low.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides an adjustable multi-point progressive flanging forming device and method, wherein the change of the curvature of the die surface is changed by adjusting the extension and contraction of an adjusting rod component until the shape of the curved surface of a to-be-formed piece is preset; the adjusting rod assemblies are cooperatively controlled, so that the change of curvatures of different die surfaces is realized, and the flanging forming of materials with different sizes by the same platform is realized.
The invention is realized by the following technical scheme:
the invention relates to an adjustable multipoint progressive flanging forming device, which comprises: hold-down mechanism, flexible bullet pad subassembly and a plurality of range upon range of regulating lever subassembly that from top to bottom set gradually and be used for the six degrees of freedom work ends that take shape, wherein: one end of the piece to be formed is arranged between the pressing mechanism and the flexible elastic cushion assembly, the flexible elastic cushion assembly envelopes the outer surface formed by one side of the stacked adjusting rod assembly, and the six-degree-of-freedom working end is positioned on the outer side of the piece to be formed to bend and deform the piece.
The regulation pole subassembly include: electric putter and the regulation pole that links to each other with it and at least one steel ball that passes through the connecting pin activity and sets up in adjusting the pole, wherein: the electric push rod is connected with the adjusting rod through the coupler, and at least one steel ball is in point contact with the flexible elastic cushion component.
The regulation pole subassembly link to each other with adjustable multiple spot turn-ups electronic control unit that advances gradually in order to realize the independent control of every regulation pole subassembly and the adjustment of envelope surface shape, this adjustable multiple spot turn-ups electronic control unit that advances gradually includes: information receiving module, information contrast calculation module and turn-ups control module, wherein: the information receiving module is connected with the grating type displacement sensor and transmits displacement information, the information comparison and calculation module is used for carrying out comparison and calculation with a theoretical result according to the displacement information to obtain local adjustment displacement, the flanging control module is used for carrying out springback compensation by regulating and controlling the adjusting rod assembly according to the local adjustment displacement information, and the circular iteration is carried out until a qualified flanging part is formed.
The invention relates to an adjustable multi-point progressive flanging forming method of the device, which is characterized in that the expansion and contraction of an adjusting rod component are adjusted by an adjustable multi-point progressive flanging electronic control unit according to the curved surface processing requirement of a piece to be formed until the envelope curved surface of the adjusting rod component conforms to the shape of the preset curved surface of the piece to be formed, and then the forming is realized by a six-degree-of-freedom working end.
Technical effects
The invention integrally solves the problems of low utilization rate of the die and long production period of the existing flanging forming technology; and the flanging rebound cannot be locally and accurately regulated and controlled;
compared with the prior art, the adjustable multi-point gradual flanging electronic control unit adjusts the expansion of the adjusting rod assembly, the position of the adjusting rod assembly is adjusted in a targeted and local mode to change the change of the curvature of the die surface until the shape of the curved surface of a piece to be formed is preset, and the adjustable multi-point gradual flanging electronic control unit has the characteristics of flexibility, no die, reconfigurable curved surface and the like, can finish flanging forming of materials with different sizes on the same platform, is efficient and quick, adapts to field adjustment operation, greatly reduces the development cycle of the formed piece, can compensate and adjust the rebound quantity in real time, and can effectively solve the problem of low utilization rate of dies.
Drawings
FIG. 1 is a schematic view of the apparatus of the present invention;
FIG. 2 is a schematic cross-sectional view of a flexible spring washer assembly;
FIG. 3 is a schematic cross-sectional view of the adjustment lever assembly;
FIG. 4 is a flow chart of the method of the present invention;
FIG. 5 is a schematic cross-sectional view of a shaped piece of the present invention;
FIG. 6 is a graph of variation of the die gap with multiple adjustments of the compensation amount according to an embodiment;
in the figure: 1 hold-down mechanism, 2 flexible bullet pad subassemblies, 3 regulating lever subassemblies, 4 grating formula linear displacement sensor, 5 adjustable multiple spot turn-ups electronic control unit that advances gradually, 6 spinning wheels, 21 polyurethane backing plates, 23 steel backing plates, 31 electric putter, 33 shaft couplings, 35 regulation poles, 37 steel balls, 39 connecting pin, 351 cylinder, 352 cylinder, 7 treat the forming part.
Detailed Description
As shown in fig. 1 and fig. 2, the present embodiment relates to an adjustable multi-point progressive flanging forming device, which includes: hold-down mechanism 1, flexible bullet pad subassembly 2 and a plurality of range upon range of regulation pole subassembly 3 that from top to bottom set gradually and be used for six degrees of freedom work ends 6 that take shape, wherein: one end of a to-be-formed part 7 is arranged between the pressing mechanism 1 and the flexible elastic cushion assembly 2, the flexible elastic cushion assembly 2 envelops the outer surface formed by one side of the stacked adjusting rod assembly 3, and the six-degree-of-freedom working end 6 is positioned on the outer side of the to-be-formed part 7 to perform bending deformation on the to-be-formed part.
As shown in fig. 2, the flexible spring-loaded pad assembly 2 includes: at least one steel backing plate 23 and the corresponding polyurethane backing plate 21 arranged on the two sides of the steel backing plate are specifically of a sandwich structure of polyurethane backing plate-steel backing plate-polyurethane backing plate or two structural forms of a five-layer sandwich structure of polyurethane backing plate-steel backing plate-polyurethane backing plate, and flexible elastic cushion assemblies with different specifications are selected according to the requirement of the flanging curvature size of the piece to be formed 7.
The polyurethane backing plate 21 and the steel backing plate 23 are preferably connected by an adhesive.
As shown in fig. 1, one end of the flexible elastic cushion component 2 is provided with a grating type linear displacement sensor 4 for detecting the size displacement change of a to-be-formed piece 7, when the to-be-formed piece is subjected to displacement change and deformation displacement rebound in the forming process, two gratings in the grating type linear displacement sensor 4 can generate relative displacement, the light intensity on the photocell can change along with the movement of moire fringes, a counter can record the number of the fringes passed by the movement of the gratings, namely the to-be-formed piece is subjected to displacement change and deformation displacement rebound amount in the forming process, and finally, the grating type linear displacement sensor 4 inputs displacement information into the adjustable multi-point progressive flanging electronic control unit 5 in a voltage signal mode so as to realize independent rebound compensation control of each adjusting rod component 3.
As shown in fig. 3, the adjusting lever assembly 3 includes: the electric push rod 31, the adjusting rod 35 connected with the electric push rod and at least one steel ball 37 movably arranged in the adjusting rod 35 through a connecting pin 39, wherein: the electric push rod 31 and the adjusting rod 35 are connected through the coupler 33, and at least one steel ball 37 is in point contact with the flexible spring washer component 2.
The adjusting rod 35 is of a two-section cylindrical structure, the diameter of one section of the cylinder 351 is larger than that of the other section of the cylinder 352, the steel ball 37 is fixedly arranged on the cylinder 352, and the diameter of the steel ball 37 is directly equal to that of the cylinder 351.
The adjusting rod assemblies 3 are orderly arranged in the longitudinal direction, the number of the adjusting rod assemblies 3 in the longitudinal direction is 4-6, the number of the steel balls 37 on the adjusting rod assemblies 3 is arranged in an arithmetic progression in the longitudinal direction, and the number of the steel balls on the adjusting rod assembly on the lower layer is 1-2 more than that on the adjusting rod assembly on the upper layer.
As shown in fig. 3, the adjusting rod assemblies 3 are all controlled individually, and each adjusting rod assembly 3 can reach its own designated position under the control of the adjustable multi-point progressive flanging electronic control unit 5.
The lamination refers to: a mounting gap of 0.5-1.0 mm is reserved between every two layers of adjusting rod assemblies 3, so that the adjusting rod assemblies 3 are prevented from interfering with each other in the telescopic process; lubricating oil is coated between the adjusting rod assemblies 3, and friction of the adjusting rod assemblies 3 in the telescopic process is reduced.
As shown in fig. 4, the method for forming an adjustable multi-point progressive flanging relating to the above device in this embodiment includes:
firstly, calculating flanging curvature data according to the flanging requirement of a to-be-formed part;
secondly, importing data into an adjustable multi-point progressive flanging electronic control unit 5, and regulating and controlling an adjusting rod component 3 to reach an appointed position to form a multi-point enveloping surface;
thirdly, performing adjustable multipoint progressive flanging finite element analysis on the to-be-formed piece, deforming the to-be-formed piece and the flexible elastic cushion assembly 2 with a certain bending curvature under the action of a tool head 6 of which the pose is controlled by an industrial six-axis robot, rebounding the to-be-formed piece after forming, and obtaining a relation between flanging curvature and rebound compensation amount through finite element analysis;
and fourthly, carrying out experimental verification and optimization on a finite element analysis result, under the action of a tool head 6 for controlling the pose of an industrial six-axis robot, detecting the size displacement change of the formed piece in the forming process by a grating type linear displacement sensor 4 arranged on the flexible elastic cushion assembly 2, inputting the displacement information of the grating type linear displacement sensor 4 to an adjustable multi-point progressive flanging electronic control unit 5, regulating and controlling the adjusting rod assembly 3 by the adjustable multi-point progressive flanging electronic control unit 5 to carry out springback compensation, optimizing the relational expression between flanging curvature and springback compensation quantity, and enabling the obtained relational expression to meet the flanging requirement of the formed piece.
And fifthly, inputting the obtained relational expression into an adjustable multi-point progressive flanging electronic control unit 5, and regulating an adjusting rod component 3 by the adjustable multi-point progressive flanging electronic control unit 5 to reach an appointed position according to the flanging requirement of the piece to be formed so as to form the required flanging piece.
And sixthly, under the action of the six-degree-of-freedom working end 6, the flexible elastic cushion component 2 is tightly attached to the piece to be formed to generate bending deformation, and the bending curvature of the flexible elastic cushion component 2 is equal to that of the piece to be formed.
As shown in fig. 1, 2 and 4, the to-be-formed member 7 is disposed on the upper surface of the flexible elastic cushion assembly 2, the flexible elastic cushion assembly 2 is a plane before forming, under the action of the six-degree-of-freedom working end 6, the flexible elastic cushion assembly 2 is tightly attached to the to-be-formed member 7 to be subjected to bending deformation, the bending curvature of the flexible elastic cushion assembly 2 is equal to that of the to-be-formed member 7, and the flexible elastic cushion assembly 2 and the to-be-formed member 7 are subjected to bending deformation at equal time, equal curvature and equal speed.
As shown in fig. 1 and 4, the six-degree-of-freedom working end 6 is driven by a six-axis robot, and the six-degree-of-freedom working end 6 has 6 degrees of freedom and can perform and rotate in the axial direction, the radial direction and the circumferential direction.
Referring to fig. 5, the 6063 aluminum alloy plate material to be formed into a piece 7 of 2mm thickness according to the embodiment has the target sizes of the flanged piece: the radius of the arc is 1000mm, and the curvature is 0.001.
Specifically, according to the flanging requirement of the to-be-formed part 7, flanging curvature data is calculated; data are imported into an adjustable multi-point progressive flanging electronic control unit 5, and an adjusting rod component 3 is regulated to reach an appointed position to form a multi-point enveloping surface; under the action of the six-degree-of-freedom working end 6, the piece to be formed 7 and the flexible elastic cushion assembly 2 deform with a certain bending curvature, and finally the required flanging piece is formed.
Through specific experiments, the maximum die attaching gap of the flanging piece obtained by the method is smaller than 0.5mm and far smaller than the maximum die attaching gap of 2.85mm obtained by the existing flanging forming technology.
Compared with the prior flanging technology which needs 10 hours of working time for one-time die repair and needs multiple die repair, the invention calculates and adjusts the position of the adjusting rod component 3 according to the rebound amount of the part, and the time for finally forming the qualified part is only 0.6 hour, thereby greatly improving the forming efficiency; compared with the prior art that the maximum die attaching gap of the flanging piece is 2.85mm, the forming method can enable the maximum die attaching gap to be smaller than 0.5mm, and obviously improves the forming quality.
The foregoing embodiments may be modified in many different ways by those skilled in the art without departing from the spirit and scope of the invention, which is defined by the appended claims and all changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (6)

1. The utility model provides a gradual turn-ups forming device of adjustable multiple spot which characterized in that includes: hold-down mechanism, flexible bullet pad subassembly and a plurality of range upon range of regulating lever subassembly that from top to bottom set gradually and be used for the six degrees of freedom work ends that take shape, wherein: one end of the piece to be formed is arranged between the pressing mechanism and the flexible elastic cushion assembly, the flexible elastic cushion assembly envelopes the outer surface formed by one side of the stacked adjusting rod assembly, namely an envelope curved surface, and the six-degree-of-freedom working end is positioned on the outer side of the piece to be formed to bend and deform the piece to be formed;
the regulation pole subassembly include: electric putter and the regulation pole that links to each other with it and at least one steel ball that passes through connecting pin activity setting in adjusting the pole, wherein: the electric push rod is connected with the adjusting rod through the coupler, and at least one steel ball is in point contact with the flexible elastic cushion component.
2. The adjustable multi-point progressive flanging forming device of claim 1, wherein the adjusting rod is of a two-section cylindrical structure, the diameter of one section of cylinder is larger than that of the other section of cylinder, the steel ball is fixedly arranged on the cylinder, and the diameter of the steel ball is directly equal to that of the cylinder.
3. The adjustable multi-point progressive flanging forming device according to claim 1, wherein the adjusting rod assemblies are orderly arranged in the longitudinal direction, the number of the adjusting rod assemblies in the longitudinal direction is 4-6, the number of the steel balls on the adjusting rod assemblies in the longitudinal direction is in an arithmetic progression arrangement, and the number of the steel balls on the adjusting rod assembly on the lower layer is 1-2 more than the number of the steel balls on the adjusting rod assembly on the upper layer.
4. The adjustable multi-point progressive flanging forming device according to claim 1 or 2, wherein the adjusting rod assemblies are connected with an adjustable multi-point progressive flanging electronic control unit to realize independent control of each adjusting rod assembly and adjustment of the shape of the envelope surface, and the adjustable multi-point progressive flanging electronic control unit comprises: information receiving module, information contrast calculation module and turn-ups control module, wherein: the information receiving module is connected with the grating type displacement sensor and transmits displacement information, the information comparison and calculation module is used for carrying out comparison and calculation with a theoretical result according to the displacement information to obtain local adjustment displacement, the flanging control module is used for carrying out springback compensation by regulating and controlling the adjusting rod assembly according to the local adjustment displacement information, and the circular iteration is carried out until a qualified flanging part is formed.
5. The adjustable multi-point progressive flanging forming device according to claim 1 or 2, wherein the stacking means: a mounting gap of 0.5-1.0 mm is reserved between each layer of adjusting rod components, so that the adjusting rod components are prevented from interfering with each other in the telescopic process; lubricating oil is coated between the adjusting rod assemblies, and friction of the adjusting rod assemblies in the telescopic process is reduced.
6. The adjustable multi-point progressive flanging forming method of the forming device according to any one of claims 1 to 5, characterized in that the expansion and contraction of the adjusting rod assembly are adjusted by the adjustable multi-point progressive flanging electronic control unit according to the curved surface processing requirements of the to-be-formed piece until the envelope curved surface of the adjusting rod assembly conforms to the shape of the preset curved surface of the to-be-formed piece, and then the forming is realized by the six-degree-of-freedom working end.
CN202111024449.8A 2021-09-02 2021-09-02 Adjustable multi-point progressive flanging forming device and method Active CN113715308B (en)

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JP5027459B2 (en) * 2006-07-25 2012-09-19 本田技研工業株式会社 Hemming processing method and hemming processing apparatus
JP5971226B2 (en) * 2013-11-01 2016-08-17 株式会社安川電機 Robot system and method of manufacturing workpiece
JP6405961B2 (en) * 2014-03-06 2018-10-17 日産自動車株式会社 Roll hemming method and roll hemming apparatus
CN104492894A (en) * 2014-12-17 2015-04-08 浙江聚英风机工业有限公司 Full automatic efficient flanging machine
JP6405994B2 (en) * 2014-12-25 2018-10-17 日産自動車株式会社 Roll hemming machine
CN106903233B (en) * 2017-04-09 2018-10-12 安徽同步自动化科技有限公司 A kind of positioning clamping device
CN207839725U (en) * 2018-01-25 2018-09-11 包头市新爱科风机制造有限责任公司 A kind of ventilating draught fan air inlet spinning flange special plane
CN112792219A (en) * 2021-01-29 2021-05-14 赵雪蕾 Plate multipoint progressive forming numerical control supporting device and numerical control multipoint progressive forming method

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