CN112916683B - Online bending forming method for composite radius strip-shaped product part - Google Patents

Online bending forming method for composite radius strip-shaped product part Download PDF

Info

Publication number
CN112916683B
CN112916683B CN202011532541.0A CN202011532541A CN112916683B CN 112916683 B CN112916683 B CN 112916683B CN 202011532541 A CN202011532541 A CN 202011532541A CN 112916683 B CN112916683 B CN 112916683B
Authority
CN
China
Prior art keywords
coordinate system
forming
arc
center
mold
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202011532541.0A
Other languages
Chinese (zh)
Other versions
CN112916683A (en
Inventor
高亚南
徐锋
李彦波
赵敏强
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ling Yun Industrial Corp Ltd
Ling Yun Industrial Co Ltd Automotive Parts R&D Branch
Original Assignee
Ling Yun Industrial Corp Ltd
Ling Yun Industrial Co Ltd Automotive Parts R&D Branch
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ling Yun Industrial Corp Ltd, Ling Yun Industrial Co Ltd Automotive Parts R&D Branch filed Critical Ling Yun Industrial Corp Ltd
Priority to CN202011532541.0A priority Critical patent/CN112916683B/en
Publication of CN112916683A publication Critical patent/CN112916683A/en
Application granted granted Critical
Publication of CN112916683B publication Critical patent/CN112916683B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D7/00—Bending rods, profiles, or tubes
    • B21D7/02—Bending rods, profiles, or tubes over a stationary forming member; by use of a swinging forming member or abutment
    • B21D7/024—Bending rods, profiles, or tubes over a stationary forming member; by use of a swinging forming member or abutment by a swinging forming member
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D53/00—Making other particular articles
    • B21D53/88—Making other particular articles other parts for vehicles, e.g. cowlings, mudguards

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Bending Of Plates, Rods, And Pipes (AREA)

Abstract

An on-line bending forming method for a composite radius strip-shaped product piece is implemented on a roll bending forming production line by utilizing a profiling mold, and comprises the following steps: a. preparing a profiling mold; b. designing a motion trail of a central control point O of a profiling mold shaft hole in the bending forming process of a product part; c. and (3) bending the composite radius strip-shaped product. The method uses the profiling mold to cooperate with a rolling production line to carry out on-line bending forming, is a forming method which is obviously different from the prior art, has the advantages of profiling forming and roll bending forming, uses the non-circular profiling mold to carry out bending forming, and is equivalent to the actual motion form of the profiling mold with different radius combinations through the translation and rotation coupling motion of the control point of the profiling mold, thereby realizing the compound radius bending forming of the strip-shaped workpiece. The method can realize the continuous production of bending and forming of the strip-shaped product with the composite radius without complex servo control, and has compact space size of the die and the equipment, thereby being convenient to realize.

Description

Online bending forming method for composite radius strip-shaped product part
Technical Field
The invention relates to a deformation processing method, in particular to an online bending forming method for a composite radius strip-shaped product piece.
Background
One important class of products that is important for composite radius bar-shaped product parts is automotive parts. The existing bending forming process method of the composite radius strip-shaped product is mainly divided into three types, namely: the three types of forming methods respectively have advantages and disadvantages, namely press bending forming based on stamping equipment, stretch bending forming based on stretch bending equipment and roll bending forming based on rolling equipment. The press bending forming and the stretch bending forming belong to the one-step forming of profiling, a profiling mold similar to the arc profile of a product piece is required to be provided, and the press bending forming and the stretch bending forming can only be produced in a single piece and cannot be used on a continuous production line such as a rolling line. Roll bending forming belongs to continuous forming, and is divided into off-line single piece production and on-line continuous production, and both the off-line single piece production and the on-line continuous production depend on roll forming. In the prior art, when the on-line composite radius forming is realized by roll forming, a roller needs to be subjected to complex servo control, two sections of fixed arcs cannot be tangent, and a transition arc section inevitably exists between two sections of different radii and radians, so that the precision of one-step forming by using a profiling mold cannot be achieved. In addition, in order to ensure the forming stability, the repeated positioning precision of the roller is required to be very high in the roller arc forming, so that the control cost of the equipment is obviously improved.
Disclosure of Invention
The invention aims to solve the problems in the prior art and provides an online bending forming method for a composite radius strip product piece, which uses a profiling mold to carry out continuous forming and has the advantages of profiling forming and roll bending forming.
The problem of the invention is realized by the following technical scheme:
an on-line bending forming method for a composite radius strip-shaped product piece is implemented on a roll bending forming production line by utilizing a profiling mold, the composite radius strip-shaped product piece is a strip-shaped product piece with two or more arc sections with different radiuses in the extension degree direction, and the method comprises the following steps:
a. preparing a profiling mold: the profiling mold is a non-circular mold, a forming section is arranged on a forming working surface of the profiling mold, the forming section is completely matched with the outline of the composite radius strip-shaped product part, and the profiling mold is provided with a mold shaft hole;
b. designing the motion trail of a central control point O of a shaft hole of a profiling mold in the bending forming process of a product piece:
establishing a global absolute coordinate system x-y, wherein the origin of the global absolute coordinate system is an absolute zero point, the method is used as a graph method, according to the forming sequence of each arc segment of a strip product, the coordinate value and the rotation initial angle value of each segment of arc in the global coordinate system are sequentially measured step by step in the graph, and then the coordinate values and the rotation initial angle values are sequentially substituted into a uniform expression of an O track equation of a control point at the center of a shaft hole, so that a required motion track equation is obtained;
for a multi-arc bar product piece and a corresponding profiling mold, the known quantities are:
RONOThe distance from the central control point O of the shaft hole to the center ON of the Nth arc is a constant value,
θNR-the N-th arc central angle is constant;
the track equation of the central control point O of the mould shaft hole of each arc is constructed as follows:
step 1, forming an arc segment of a product piece R1:
within the global absolute coordinate system x-y, the absolute coordinates of the center O1 of the arc R1 of the product piece are measured as (O1x, O1 y). The profiling mold rotates around the center O1 of the arc segment R1, a local coordinate system x1-y1 is established at O1, and the track equation of the control point O at the center of the mold shaft hole under the local coordinate system can be obtained as follows:
Figure BDA0002852441460000021
wherein:
Ox1-O abscissa values under the local coordinate system x1-y 1;
Oy1-ordinate values of O under the local coordinate system x1-y 1;
RO1O-the distance O from the centre O1, i.e. the radius of rotation, is known to a fixed value;
the angle of rotation theta 1-O about the center O1, which is equal to the central angle theta 1 of arc R1RThe same;
ω1-the angular velocity of the mould 2 around the centre O;
t-time;
θ1sr before the start of the rotation in the local coordinate system x1-y1O1OThe included angle between the horizontal coordinate and the horizontal coordinate is obtained by graph measurement;
θ1eunder the local coordinate system x1-y1, R after the rotation is finishedO1OAngle with respect to the abscissa, θ 1e＝θ1s-θ1R；
Transforming the trajectory equation to a global absolute coordinate system x-y, the expression is as follows:
Figure BDA0002852441460000031
step 2, arc forming of a strip-shaped product piece R2:
In the global absolute coordinate system x-y, the absolute coordinates of the center O2 of the arc segment R2 of the product piece are measured as (O2x, O2 y). The profiling mold rotates around the center O2 of the arc segment R2, a local coordinate system x2-y2 is established at O2, and the track equation of the control point O at the center of the mold shaft hole under the local coordinate system can be obtained as follows:
Figure BDA0002852441460000032
wherein:
Ox2-O abscissa values under the local coordinate system x2-y 2;
Oy2-ordinate values of O under the local coordinate system x2-y 2;
RO2O-the distance O from the centre O2, i.e. the radius of rotation, is known to a fixed value;
angle of rotation theta 2-O about center O2 of angle theta 2 with respect to center angle theta 2 of arc R2RThe same;
ω2-the angular velocity of the mould 2 around the centre O;
t-time;
θ2sr before the start of the rotation in the local coordinate system x2-y2O2OThe included angle between the horizontal coordinate and the horizontal coordinate is measured in the figure;
θ2eunder the local coordinate system x2-y2, R after the rotation is finishedO2OAngle of inclination with respect to the abscissa, theta 2e＝θ2s-θ2R。
Transforming the trajectory equation to a global absolute coordinate system x-y, the expression is as follows:
Figure BDA0002852441460000033
and 3, step 3: r3 arc segment forming of strip-shaped product
In the global absolute coordinate system x-y, the absolute coordinates of the center O3 of the arc segment R3 of the product piece are measured as (O3x, O3 y). The profiling mold rotates around the center O3 of the arc segment R3, a local coordinate system x3-y3 is established at O3, and the track equation of the control point O at the center of the mold shaft hole under the local coordinate system can be obtained as follows:
Figure BDA0002852441460000041
Wherein:
Ox3-O abscissa values under the local coordinate system x3-y 3;
Oy3-ordinate values of O under the local coordinate system x3-y 3;
RO3O-the distance O from the centre O3, i.e. the radius of rotation, is known to a fixed value;
angle of rotation theta 3-O about center O3 of angle theta 3 with respect to center angle theta 3 of arc R3RThe same;
ω3-the angular velocity of the mould 2 around the centre O;
t-time;
θ3sr before the start of the rotation in the local coordinate system x3-y3O3OAngle with abscissa, measured from the figure
Obtaining;
θ3eunder the local coordinate system x3-y3, R after the rotation is finishedO3OAngle with respect to the abscissa, θ 3e＝θ3s-θ3R。
Transforming the trajectory equation to a global absolute coordinate system x-y, the expression is as follows:
Figure BDA0002852441460000042
if the product piece is an N-section arc, according to the method, sequentially forming R4, R5, … …, RN-1 and RN arc sections, wherein the position at the end of the step N-1 is the position at the beginning of the step N, and the following steps are carried out:
and (N) step: RN arc segment forming of product part
At the beginning: in the global absolute coordinate system x-y, the absolute coordinates (ONx, ONy) of the circle center ON of the arc section RN of the product can be measured. The profiling mold rotates around the circle center ON of the RN arc section, a local coordinate system xN-yN is established at the ON position, and the track equation of the mold shaft hole center control point O under the local coordinate system can be obtained as follows:
Figure BDA0002852441460000043
wherein:
OxN-the abscissa value of O in the local coordinate system xN-yN;
OyN-the ordinate value of O in the local coordinate system xN-yN;
RONO-the distance O from the centre ON, i.e. the radius of rotation, is known to a fixed value;
angle of rotation of theta N-O around center ON, the value of which is related to the central angle theta N of arc section RNRThe same;
ωN-the angular velocity of the mould 2 around the centre O;
t-time;
θNsr before the start of the rotation in a local coordinate system xN-yNONOThe included angle between the horizontal coordinate and the horizontal coordinate is measured in the figure;
θNer after the end of the rotation in a local coordinate system xN-yNONOAngle with respect to the abscissa, θ Ne＝θNs-θNR。
Transforming the trajectory equation to a global absolute coordinate system x-y, the expression is as follows:
Figure BDA0002852441460000051
each arc section track curve can be obtained by the constructed RN arc section bending forming mould shaft hole track equation, and the arc section track curves are sequentially connected and combined to form a product piece rolling bending forming profiling mould shaft hole motion track;
c. bending the composite radius strip-shaped product piece: and c, moving the shaft hole of the profiling mold according to the motion trail of the shaft hole of the bending forming mold of the strip-shaped product piece obtained in the step b while the profiling mold rotates by taking the shaft hole of the mold as a center in the machining process, and performing bending forming machining on the strip-shaped product piece with the composite radius.
In the online bending forming method of the composite radius strip-shaped product part, in the step c, the forming head end of the product part is tightly pressed with the profiling mold by the forming pressing block from the beginning of forming to the completion of forming of the composite radius strip-shaped product part; and after the forming is finished, the cutting-off pressing block presses the forming tail end of the product piece, the cutting-off cutter cuts off the bent product piece, the forming pressing block and the cutting-off pressing block are separated from the product piece, and the bent composite-radius strip-shaped product piece is taken out of the profiling die.
In the method for the on-line bending forming of the composite radius strip-shaped product part, the two sides of the forming section of the forming working surface of the profiling die are respectively provided with the pressing sections, and the forming fixing block respectively corresponds to each pressing section.
According to the online bending forming method of the composite radius strip-shaped product piece, the mold shaft hole is positioned on one side, far away from the forming working surface, of the middle part of the profiling mold.
According to the online bending forming method of the composite radius strip-shaped product part, when the composite radius strip-shaped product part is a cavity, a core penetrates into the cavity of the product part in the bending process.
The method uses a profiling mold to cooperate with a rolling production line to carry out on-line bending forming, and bends a straight strip-shaped product material strip into the shape of a required strip-shaped product with a composite radius at one time. The technology of the invention is a forming method which is obviously different from the prior art, has the advantages of profile forming and roll bending forming, uses a non-circular profile modeling die to carry out bending forming, and is equivalent to the actual motion form of profile modeling dies with different radius combinations through the translation and rotation coupling motion of control points of the profile modeling die, thereby realizing the composite radius bending forming of strip workpieces. The method can realize the continuous production of bending and forming of the strip-shaped product with the composite radius without complex servo control, and the space size of the die and the equipment is compact, thereby being convenient for realizing the equipment.
Drawings
The invention will be further described with reference to the accompanying drawings.
FIG. 1 is a schematic view of a strip-form product piece being bent over a profiling die;
FIG. 2 is a schematic view of a profiling die;
FIG. 3 is a schematic illustration of a three-arc composite radius bar product piece;
FIG. 4 is a schematic diagram of the movement locus of a control point O at the center of an axle hole of a profiling mold;
FIG. 5 is a schematic illustration of a compound radius strip product piece bend forming process;
FIG. 6 is a movement locus of the center of the axial hole of the profiling die of the embodiment.
The reference numbers in the figures are: 1. the method comprises the following steps of (1) forming a strip-shaped product part, 2-1) a profiling mold, 2-2) a shaft hole center, 2-3 of a forming section, 3 of a pressing section, 4 of a forming pressing block, 5 of a cutting pressing block, 6 of a cutting knife and a movement track of a shaft hole center control point O.
Detailed Description
The composite radius strip-shaped product piece refers to a workpiece with two or more arc sections with different radiuses in the extension direction of the strip-shaped product piece. As shown in fig. 3, the curved portion of the composite radius strip-shaped product piece is composed of three arc sections with different radii, the radii of the arc sections are R1, R2 and R3, and two ends of the curved portion are straight sections. For the composite radius strip-shaped product piece with three arc sections shown in fig. 3, if the mold is formed according to the actual rotation center, the actual rotation center needs to be changed for 2 times, and so on, the N arc sections need to change the rotation center for N-1 times, which is very difficult and tedious for practical application; for a large-radius workpiece, such as an arc section with a radius of more than 2000, if the arc section is designed according to an actual rotation center, the space size of a die and equipment is huge, and the arc section has no universality and no practicability. Referring to fig. 1, the method of the invention adopts a non-circular profiling mold 2, and the actual motion form of the profiling mold with various radius combinations is equivalent by the translation and rotation coupling motion of a control point at the center 2-1 of a shaft hole of the profiling mold, thereby realizing the bending forming processing of the composite radius of a strip product 1. The method not only avoids the problem that two sections of different radiuses and radians are in transition arc sections in the conventional composite-radius strip arc processing, but also can adopt a profiling mold with a compact structure to perform online bending forming processing on the strip formed by roll pressing at the tail end of a roll pressing production line.
Referring to fig. 1 and 2, a forming section 2-2 is arranged on a forming working surface of a profiling mold 2, the forming section is completely matched with the contour of the bending part of the strip-shaped product with the composite radius, and pressing sections 2-3 are respectively arranged on two sides of the forming section. The shaft hole center 2-1 of the profiling mold is the rotating center point of the profiling mold. The material strip of the strip-shaped product piece is sent into a profiling mold 2 along the arrow direction, and the forming head end of the strip-shaped product piece and the compaction section at the feeding side of the profiling mold are tightly compacted by a forming compaction block 3 from the beginning of forming processing to the completion of forming; the bending processing of the strip-shaped product with the composite radius is realized along with the movement of the profiling mold; and after forming is completed, the forming tail end of the product piece is pressed on the pressing section of the discharge side of the profiling die by the cutting and pressing block 4, the bent product piece is cut by the cutting knife 5, then the forming and pressing block and the cutting and pressing block are separated from the product piece, and the bent product piece is taken out of the profiling die. When the composite radius strip-shaped product piece is a cavity, the core penetrates into the cavity bent into the product piece so as to control the inner arc wrinkles and avoid the serious distortion of the section shape.
The key technology of the invention is to design the motion trail of the shaft hole central control point O of the profiling mold in the bending forming process of the strip-shaped product according to each section of radian of the strip-shaped product, and the construction of the motion trail of the shaft hole central control point O is detailed in the following by combining the attached drawings.
Referring to FIG. 4, a global absolute coordinate system x-y is established with an origin of the global absolute coordinate system being an absolute zero. And (3) measuring a rotation center coordinate value (a global coordinate system) and a rotation starting angle value (a transverse coordinate axis of a local coordinate system) in turn in steps in the drawing according to the forming sequence of each arc section by using a drawing method, and then substituting the rotation center coordinate value and the rotation starting angle value into the uniform expression of the O track equation of the center control point of the shaft hole in turn to obtain the required motion track equation.
For a multi-segment arc product piece and a corresponding profiling mold, the known quantities are:
RONOcentral control point O to the second of the shaft holeThe distance of the center ON of the N sections of arcs is a fixed value;
θNRand the central angle of the Nth arc is a constant value.
Step 1: r1 arc segment forming of product piece
At the beginning: referring to FIG. 4, in the global absolute coordinate system x-y, the absolute coordinate of the center O1 of the arc R1 of the product piece is measured as (O1x, O1 y). The profiling mold rotates around the center O1 of the arc segment R1, a local coordinate system x1-y1 is established at O1, and the track equation of the control point O at the center of the mold shaft hole under the local coordinate system can be obtained as follows:
Figure BDA0002852441460000081
wherein:
Ox1-O abscissa values under the local coordinate system x1-y 1;
Oy1-ordinate values of O under the local coordinate system x1-y 1;
RO1O-the distance O from the centre O1, i.e. the radius of rotation, is known to a fixed value;
Angle of rotation of theta 1-O about center O1, which is related to central angle theta 1 of arc R1RThe same;
ω1rotating the angular speed of the die 2 around the circle center O;
t-time;
θ1sr before the start of the rotation in the local coordinate system x1-y1O1OAngle with the abscissa, measured from the figure
Obtaining;
θ1eunder the local coordinate system x1-y1, R after the rotation is finishedO1OAngle with respect to the abscissa, θ 1e＝θ1s-θ1R(ii) a Transforming the trajectory equation to a global absolute coordinate system x-y, the expression is as follows:
Figure BDA0002852441460000082
at this point, the R1 arc bending forming die shaft hole trajectory equation is constructed.
And (4) at the end: the position at the end of the step 1 is the position at the beginning of the step 2.
Step 2: r2 arc segment forming of product piece
At the beginning: referring to FIG. 4, in the global absolute coordinate system x-y, the absolute coordinates of the center O2 of the arc R2 of the product piece are measured as (O2x, O2 y). The profiling mold rotates around the center O2 of the arc segment R2, a local coordinate system x2-y2 is established at O2, and the track equation of the control point O at the center of the mold shaft hole under the local coordinate system can be obtained as follows:
Figure BDA0002852441460000091
wherein:
Ox2-O abscissa values under the local coordinate system x2-y 2;
Oy2-ordinate values of O under the local coordinate system x2-y 2;
RO2O-the distance O from the centre O2, i.e. the radius of rotation, is known to a fixed value;
angle of rotation theta 2-O about center O2 of angle theta 2 with respect to center angle theta 2 of arc R2 RThe same;
ω2rotating the angular speed of the die 2 around the circle center O;
t-time;
θ2sr before the start of the rotation in the local coordinate system x2-y2O2OThe included angle between the horizontal coordinate and the horizontal coordinate is measured in the figure;
θ2e-R after the end of the rotation in the local coordinate system x2-y2O2OAngle of inclination with respect to the abscissa, θ 2e＝θ2s-θ2R。
Transforming the trajectory equation to a global absolute coordinate system x-y, wherein the expression is as follows:
Figure BDA0002852441460000092
at this point, the R2 arc bending forming trajectory equation is constructed.
The end position of the step 2 is the start position of the step 3.
And 3, step 3: r3 arc segment forming of product piece
At the beginning: referring to FIG. 4, in the global absolute coordinate system x-y, the absolute coordinates of the center O3 of the arc R3 of the product piece are measured as (O3x, O3 y). The profiling mold rotates around the center O3 of the arc segment R3, a local coordinate system x3-y3 is established at O3, and the track equation of the control point O at the center of the mold shaft hole under the local coordinate system can be obtained as follows:
Figure BDA0002852441460000093
wherein:
Ox3-O abscissa values under the local coordinate system x3-y 3;
Oy3-ordinate values of O under the local coordinate system x3-y 3;
RO3O-the distance O from the centre O3, i.e. the radius of rotation, is known to a fixed value;
angle of rotation theta 3-O about center O3 of angle theta 3 with respect to center angle theta 3 of arc R3RThe same;
ω3-the angular velocity of the mould 2 around the centre O;
t-time;
θ3sr before the start of the rotation in the local coordinate system x3-y3 O3OThe included angle between the horizontal coordinate and the horizontal coordinate is measured in the figure;
θ3e-R after the end of the rotation in the local coordinate system x3-y3O3OAngle of inclination with respect to the abscissa, [ theta ] 3e＝θ3s-θ3R。
Transforming the trajectory equation to a global absolute coordinate system x-y, wherein the expression is as follows:
Figure BDA0002852441460000101
so far, the construction of the R3 arc bending forming track equation is completed.
And (4) at the end: and if the product piece is 3 arcs, finishing the whole forming process when the step 3 is finished. And if the product is an arc with N (N is more than or equal to 4), the position at the end of the step 3 is the position at the beginning of the step 4.
And by analogy, sequentially forming R4, R5, … …, RN-1 and RN arc sections, wherein the position of the end of the step N-1 is the position of the start of the step N. Then there is
And (N) step: RN arc segment forming of product part
At the beginning: in the global absolute coordinate system x-y, the absolute coordinates (ONx, ONy) of the circle center ON of the arc section RN of the product can be measured. The profiling mold rotates around the circle center ON of the RN arc section, a local coordinate system xN-yN is established at the ON position, and the track equation of the mold shaft hole center control point O under the local coordinate system can be obtained as follows:
Figure BDA0002852441460000102
wherein:
OxN-the abscissa value of O in the local coordinate system xN-yN;
OyN-a longitudinal coordinate value of O in a local coordinate system xN-yN;
RONO-the distance O from the centre ON, i.e. the radius of rotation, is known to a fixed value;
Angle of rotation of theta N-O around center ON, the value of which is related to the central angle theta N of arc section RNRThe same;
ωN-the angular velocity of the mould 2 around the centre O;
t-time;
θNsr before the start of rotation in a local coordinate system xN-yNONOThe included angle between the horizontal coordinate and the horizontal coordinate is measured in the figure;
θNer after the end of the rotation in a local coordinate system xN-yNONOAngle with respect to the abscissa, θ Ne＝θNs-θNR。
Transforming the trajectory equation to a global absolute coordinate system x-y, the expression is as follows:
Figure BDA0002852441460000111
and at this point, the RN arc bending forming track equation is constructed.
And (4) at the end: and (4) if the product is N-segment arcs, finishing the whole forming process when the Nth step is finished.
Formula 5) -formula 6) is a general calculation formula of the motion trajectory control equation of the forming control point O of the N-section arc product part, and the 1 st to Nth step trajectory equation expressions can be sequentially obtained through N-step calculation by combining with the measured value of the drawing method, and all expressions are integrated to obtain the motion trajectory overall control equation of the forming control point O of the N-section arc workpiece.
Referring to fig. 5, after all control equations of the motion trajectory of the forming control point O of the N-segment arc workpiece are constructed, the motion trajectory of the control point O can be drawn: and sequentially drawing N control point O track curves to form a product bending forming profiling mold shaft hole O motion track 6.
One specific example is given below:
the composite radius bar product piece is shown in fig. 3, where R1 is 1000mm and R1 central angle θ 1R11.46 degrees, 3000mm for R2, and central angle theta 2 for R2R9.55 deg., 1000mm R3, R3 central angle theta 3R11.46 deg.. And 3, completing the calculation of the control point O track equation.
Referring to fig. 4, step 1: product piece R1 arc segment forming
At the beginning: referring to fig. 4, in the global absolute coordinate system x-y, the absolute coordinate of the center O1 of the arc R1 of the product piece is (O1x, O1y) ═ 300,300. The profiling mold rotates around the center O1 of the arc segment R1, a local coordinate system x1-y1 is established at O1, measured by formula 6) and shown in the figure, and
RO1O＝695.85mm，θ1s＝120.24°，θ1e＝θ1s-θ1R＝108.78°
the track equation of the central control point O of the mold shaft hole under the obtained local coordinate system is as follows:
Figure BDA0002852441460000121
at this point, the R1 arc bending forming die shaft hole trajectory equation is constructed.
And (4) at the end: the position at the end of the step 1 is the position at the beginning of the step 2.
Step 2: r2 arc segment forming of product piece
At the beginning: referring to fig. 4, in the global absolute coordinate system x-y, the absolute coordinate of the center O2 of the arc R2 of the product piece is (O2x, O2y) — (300, -1700). The profiling mold rotates around the center O2 of the arc segment R2, a local coordinate system x2-y2 is established at O2, and measured by formula 6) and the figure is as follows:
RO2O＝2669.4mm，θ2s＝94.78°，θ2e＝θ2s-θ2R＝85.23°
The equation of the track of the control point O at the center of the mold shaft hole under the obtained local coordinate system is as follows:
Figure BDA0002852441460000122
at this point, the R2 arc bending forming trajectory equation is constructed.
And (4) at the end: the end position of the step 2 is the start position of the step 3.
And 3, step 3: r3 arc segment forming of product piece
At the beginning: referring to fig. 4, in the global absolute coordinate system x-y, the absolute coordinate of the center O2 of the arc R3 of the product piece is (O3x, O3y) ═ 300,300. The profiling mold rotates around the center O3 of the arc segment R3, a local coordinate system x3-y3 is established at O3, measured by formula 6) and shown in the figure, and
RO3O＝695.85mm，θ3s＝71.59°，θ3e＝θ3s-θ3R＝60.13°
the track equation of the central control point O of the mold shaft hole under the obtained local coordinate system is as follows:
Figure BDA0002852441460000123
at this point, the R3 arc bending forming trajectory equation is constructed.
And (4) synthesizing a), b) and c), namely obtaining a track equation under the global coordinate system of the shaft hole of the mold in the forming process, and obtaining the motion track of the control point O at the center of the shaft hole according to the equation, wherein the motion track is shown in FIG. 6.
The bending processing process of the composite radius of the strip-shaped product part is characterized in that a profiling mold is installed on a corresponding forming device, the forming device is positioned at the tail end of a rolling production line, and a strip material formed by rolling enters the profiling mold to be bent and formed. When the die shaft hole is used as the center to rotate, the center of the shaft hole of the profiling die moves according to the motion track of the shaft hole shown in figure 6, and the strip-shaped product is bent.
The T-point in fig. 4 is the contact point when the straight bar gradually enters the profiling die during the forming process.

Claims (5)

1. An online bending forming method for a composite radius strip-shaped product part is characterized by comprising the following steps: the method is implemented on a roll bending forming production line by utilizing a profiling mold, the composite radius strip-shaped product piece is a strip-shaped product piece with more than two arc sections with different radiuses along the length direction, and the method comprises the following steps:
a. preparing a profiling mold: the profiling mold is a non-circular mold, a forming section is arranged on a forming working surface of the profiling mold, the forming section is completely matched with the profile of the strip-shaped product part with the composite radius, and the profiling mold is provided with a mold shaft hole;
b. designing the motion trail of a control point O at the center of a shaft hole of a profiling mold in the bending forming process of a product piece:
establishing a global absolute coordinate system x-y, wherein the origin of the global absolute coordinate system is an absolute zero point, the method is used as a graph method, according to the forming sequence of each arc segment of a strip product, the coordinate value and the rotation initial angle value of each segment of arc in the global coordinate system are sequentially measured step by step in the graph, and then the coordinate values and the rotation initial angle values are sequentially substituted into a uniform expression of an O track equation of a control point at the center of a shaft hole, so that a required motion track equation is obtained;
for a multi-arc bar product piece and a corresponding profiling mold, the known quantities are:
RONOIn-shaft holesThe distance from the center control point O to the center ON of the Nth arc is a fixed value;
θNR-the N-th arc central angle is constant;
the trajectory equation of the central control point O of the mould shaft hole of each arc is constructed as follows:
step 1, forming an arc segment of a product piece R1:
in a global absolute coordinate system x-y, measuring the absolute coordinates of the center O1 of an arc section R1 of a product piece as (O1x, O1y), rotating a copying mold around the center O1 of the arc section R1, establishing a local coordinate system x1-y1 at O1, and obtaining a track equation of a control point O at the center of an axial hole of the mold under the local coordinate system as follows:
Figure FDA0003547775120000011
wherein:
Ox1-O abscissa values under the local coordinate system x1-y 1;
Oy1-ordinate values of O under the local coordinate system x1-y 1;
RO1O-the distance O from the centre O1, i.e. the radius of rotation, is known to a fixed value;
the angle of rotation theta 1-O about the center O1, which is equal to the central angle theta 1 of arc R1RThe same;
ω1-the angular velocity of the mould 2 around the centre O;
t-time;
θ1sr before the start of the rotation in the local coordinate system x1-y1O1OThe included angle between the horizontal coordinate and the horizontal coordinate is obtained by graph measurement;
θ1eunder the local coordinate system x1-y1, R after the rotation is finishedO1OAngle of inclination with respect to the abscissa, [ theta ] 1e＝θ1s-θ1R(ii) a Transforming the trajectory equation to a global absolute coordinate system x-y, the expression is as follows:
Figure FDA0003547775120000021
step 2, arc forming of a strip-shaped product part R2:
In the global absolute coordinate system x-y, the absolute coordinates of the center O2 of the arc section R2 of the product piece are measured to be (O2x, O2y), the copying mold rotates around the center O2 of the arc section R2, a local coordinate system x2-y2 is established at the position O2, and the track equation of the control point O at the center of the shaft hole of the mold in the local coordinate system is obtained as follows:
Figure FDA0003547775120000022
wherein:
Ox2-O abscissa values under the local coordinate system x2-y 2;
Oy2-O is an ordinate value under the local coordinate system x2-y 2;
RO2O-the distance O from the centre O2, i.e. the radius of rotation, is known to a fixed value;
angle of rotation theta 2-O about center O2 of angle theta 2 with respect to center angle theta 2 of arc R2RThe same;
ω2-the angular velocity of the mould 2 around the centre O;
t-time;
θ2sr before the start of the rotation in the local coordinate system x2-y2O2OThe included angle between the horizontal coordinate and the horizontal coordinate is measured in the figure;
θ2eunder the local coordinate system x2-y2, R after the rotation is finishedO2OAngle of inclination with respect to the abscissa, theta 2e＝θ2s-θ2R；
Transforming the trajectory equation to a global absolute coordinate system x-y, the expression is as follows:
Figure FDA0003547775120000031
and 3, step 3: r3 arc segment forming of strip-shaped product
In the global absolute coordinate system x-y, the absolute coordinates of the center O3 of the arc section R3 of the product part are measured to be (O3x, O3y), the profiling mold rotates around the center O3 of the arc section R3, a local coordinate system x3-y3 is established at O3, and the track equation of the control point O at the center of the mold shaft hole in the local coordinate system can be obtained as follows:
Figure FDA0003547775120000032
Wherein:
Ox3-O abscissa values under the local coordinate system x3-y 3;
Oy3-ordinate values of O under the local coordinate system x3-y 3;
RO3O-the distance O from the centre O3, i.e. the radius of rotation, is known to a fixed value;
angle of rotation theta 3-O about center O3 of angle theta 3 with respect to center angle theta 3 of arc R3RThe same;
ω3-the angular velocity of the mould 2 around the centre O;
t-time;
θ3sr before the start of the rotation in the local coordinate system x3-y3O3OThe included angle between the horizontal coordinate and the horizontal coordinate is measured in the figure;
θ3eunder the local coordinate system x3-y3, R after the rotation is finishedO3OAngle with respect to the abscissa, θ 3e＝θ3s-θ3R；
Transforming the trajectory equation to a global absolute coordinate system x-y, the expression is as follows:
Figure FDA0003547775120000033
if the product piece is an N-section arc, according to the method, sequentially forming R4, R5, … …, RN-1 and RN arc sections, wherein the position at the end of the step N-1 is the position at the beginning of the step N, and the following steps are carried out:
and (N) step: RN arc segment forming of product part
At the beginning: in the global absolute coordinate system x-y, the absolute coordinates (ONx, ONy) of the circle center ON of the RN of the product part can be measured, the copying mold rotates around the circle center ON of the RN arc, a local coordinate system xN-yN is established at the ON position, and the track equation of the mold shaft hole central control point O in the local coordinate system can be obtained as follows:
Figure FDA0003547775120000041
wherein:
OxN-the abscissa value of O in the local coordinate system xN-yN;
OyN-a longitudinal coordinate value of O in a local coordinate system xN-yN;
RONO-the distance O from the centre ON, i.e. the radius of rotation, is known to a fixed value;
angle of rotation of theta N-O around center ON, the value of which is related to the central angle theta N of arc section RNRThe same;
ωN-the angular velocity of the mould 2 around the centre O;
t-time;
θNsr before the start of rotation in a local coordinate system xN-yNONOThe included angle between the horizontal coordinate and the horizontal coordinate is measured in the figure;
θNer after the end of the rotation in a local coordinate system xN-yNONOAngle with respect to the abscissa, θ Ne＝θNs-θNR；
Transforming the trajectory equation to a global absolute coordinate system x-y, the expression is as follows:
Figure FDA0003547775120000042
each arc section track curve can be obtained by the constructed RN arc section bending forming mould shaft hole track equation, and the arc section track curves are sequentially connected and combined to form a product piece rolling bending forming profiling mould shaft hole motion track;
c. bending the composite radius strip-shaped product piece: and c, moving the shaft hole of the profiling mold according to the motion trail of the shaft hole of the bending forming mold of the strip-shaped product piece obtained in the step b while the profiling mold rotates by taking the shaft hole of the mold as a center in the machining process, and performing bending forming machining on the strip-shaped product piece with the composite radius.
2. The method of on-line bend forming of composite radius bar product pieces of claim 1, wherein: in the step c, the forming head end of the product piece is tightly pressed with the profiling mold by a forming pressing block from the beginning of forming to the completion of forming of the composite radius strip-shaped product piece; and after the forming is finished, the cutting-off pressing block presses the forming tail end of the product piece, the cutting-off cutter cuts off the bent product piece, the forming pressing block and the cutting-off pressing block are separated from the product piece, and the bent composite-radius strip-shaped product piece is taken out of the profiling die.
3. The method of on-line bend forming of composite radius bar product pieces of claim 2, wherein: and the two sides of the forming section of the forming working surface of the profiling mold are respectively provided with a pressing section, and the forming pressing blocks respectively correspond to the pressing sections.
4. The method of on-line bend forming of composite radius bar product pieces of claim 3, wherein: the mould shaft hole is positioned on one side of the middle part of the profiling mould far away from the forming working surface.
5. The method of on-line bend forming of composite radius bar product pieces of claim 4, wherein: and when the composite radius strip-shaped product piece is a cavity, a core penetrates into the cavity of the product piece in the bending process.
CN202011532541.0A 2020-12-23 2020-12-23 Online bending forming method for composite radius strip-shaped product part Active CN112916683B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011532541.0A CN112916683B (en) 2020-12-23 2020-12-23 Online bending forming method for composite radius strip-shaped product part

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011532541.0A CN112916683B (en) 2020-12-23 2020-12-23 Online bending forming method for composite radius strip-shaped product part

Publications (2)

Publication Number Publication Date
CN112916683A CN112916683A (en) 2021-06-08
CN112916683B true CN112916683B (en) 2022-06-28

Family

ID=76162765

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011532541.0A Active CN112916683B (en) 2020-12-23 2020-12-23 Online bending forming method for composite radius strip-shaped product part

Country Status (1)

Country Link
CN (1) CN112916683B (en)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4977771A (en) * 1988-12-30 1990-12-18 Usui Kokusai Sangyo Kaisha Ltd. Device for bending thin metallic pipe
CN101585062A (en) * 2008-05-21 2009-11-25 Blm有限公司 Method for bending pipes, rods, profiled sections and similar blanks, and corresponding device
CN101670393A (en) * 2009-08-26 2010-03-17 厦门市易洁卫浴有限公司 Method for realizing bending two arcs of curved pipe and device thereof
CN201596699U (en) * 2010-01-14 2010-10-06 上海海都化学科技有限公司 Material bending and forming machine tool
GB201300825D0 (en) * 2013-01-16 2013-02-27 Olicana Products Improvements in tube bending machines
CN104145120A (en) * 2012-04-10 2014-11-12 夏普株式会社 Propeller fan, fluid sending device, electric fan, and mold for molding
CN106428523A (en) * 2015-08-10 2017-02-22 空中客车美国工程有限公司 Longitudinal layer piece laying structural component of composite wing beam
CN108723131A (en) * 2018-04-27 2018-11-02 浙江大学 A kind of metal tube variable curvature bending method based on eccentric wheel

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4977771A (en) * 1988-12-30 1990-12-18 Usui Kokusai Sangyo Kaisha Ltd. Device for bending thin metallic pipe
CN101585062A (en) * 2008-05-21 2009-11-25 Blm有限公司 Method for bending pipes, rods, profiled sections and similar blanks, and corresponding device
CN101670393A (en) * 2009-08-26 2010-03-17 厦门市易洁卫浴有限公司 Method for realizing bending two arcs of curved pipe and device thereof
CN201596699U (en) * 2010-01-14 2010-10-06 上海海都化学科技有限公司 Material bending and forming machine tool
CN104145120A (en) * 2012-04-10 2014-11-12 夏普株式会社 Propeller fan, fluid sending device, electric fan, and mold for molding
GB201300825D0 (en) * 2013-01-16 2013-02-27 Olicana Products Improvements in tube bending machines
CN106428523A (en) * 2015-08-10 2017-02-22 空中客车美国工程有限公司 Longitudinal layer piece laying structural component of composite wing beam
CN108723131A (en) * 2018-04-27 2018-11-02 浙江大学 A kind of metal tube variable curvature bending method based on eccentric wheel

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
汽车梁滚压成形的数值模拟;郑邦志;《锻压技术》;20191024;94-100 *

Also Published As

Publication number Publication date
CN112916683A (en) 2021-06-08

Similar Documents

Publication Publication Date Title
TWI510305B (en) Method for bending pipes, rods, profiled sections and similar blanks, and corresponding device
Tomczak et al. Designing of screw impressions in the helical rolling of balls
CN112916683B (en) Online bending forming method for composite radius strip-shaped product part
CN107944155A (en) The 3 D auto bending process analysis method of section bar
CN108838246B (en) Method for accurately obtaining bending angle of robot
KR20060123162A (en) Cold forming method for producing ball journals
EP1097755B1 (en) Bending method for pipe material
CN201140244Y (en) Bend pipe mould apparatus
US2675049A (en) Process for the manufacture of tubular l's
CN113857323B (en) Spinning forming method of complex thin-wall variable-section component of aluminum alloy splice plate
RU2363558C1 (en) Method for profile cutting of tube ends
CN204414289U (en) Ceramic insertion core Piece rolling machine
CN208976520U (en) A kind of ball spline casing cold-drawn one-time-shaped mould
CN214108404U (en) Elbow forming machine for extruding elbow
US631851A (en) Method of and apparatus for making roll-drawn tubing.
JPS62168619A (en) Forming method for stepped pipe
CN207857580U (en) A kind of adjustable cutter structure of metal plate bending
US20120198902A1 (en) Method and device for complex forming a metal sheet by means of bodies of revolution
SU664708A1 (en) Die set for making tees
RU2087222C1 (en) Method for preparing leading ends of blanks for drawing at making manifold shapes
Feng et al. Modeling and simulation of conical bending with cylindrical rolls
JP3676139B2 (en) Control data creation method for push-through bending machine
JP2832437B2 (en) Pipe continuous bending equipment
SU1622072A1 (en) Method of hollow stepped parts
KR101600421B1 (en) Apparatus and Method for manufacturing a curved pipe and a curved pipe thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant