JPWO2017134970A1 - Work bending method and work bending apparatus - Google Patents

Abstract

It is an object of the present invention to provide a workpiece bending method and a workpiece bending apparatus capable of appropriately setting the trajectory of a processing tool based on the shape of a workpiece before processing and the target shape of a workpiece after processing. A workpiece bending method in which a bending process is performed on the flange WF of the workpiece Wa by the processing roller 10, and a process of obtaining a pre-processing angle θ 0 of the flange WF before processing and a flange length L of a bent portion of the flange WF; Based on the path determined in the path determination step, the path determination step for determining the path (trajectory) of the processing roller 10 based on the pre-processing angle θ0, the target angle Ψ after processing, and the flange length L. A processing step of moving the processing roller 10 in a predetermined direction and bending the flange WF to a target angle Ψ.

Description

  The present invention relates to a technique for bending an end portion of a workpiece with a processing tool.

  2. Description of the Related Art Conventionally, a technique is known in which a processing tool such as a hemming roller is moved while being pressed against an end portion of a plate material to bend the end portion of the plate material. For example, Patent Literature 1 discloses this type of technology. Patent Document 1 discloses a technique for learning an angle changing operation or the like between preliminary bending and main bending in a hemming apparatus that performs bending with a hemming roller.

JP-A-2-197331

  The trajectory of the processing tool for performing bending on the workpiece varies depending not only on the shape of the workpiece but also on the state of the workpiece before bending and the state of the workpiece after bending to a target angle. Since the locus of the processing tool is set based on the experience of a skilled engineer or the like, depending on the operator, it takes time to teach the processing apparatus at the site. In this regard, even in the technology disclosed in Patent Document 1 that learns in advance, learning is performed in consideration of the state of the workpiece before bending and the state of the workpiece after bending to a target angle in the trajectory of the processing tool. There is room for improvement in terms of efficiency and reproducibility.

  An object of the present invention is to provide a workpiece bending method and a workpiece bending apparatus capable of appropriately setting a locus of a processing tool based on a shape of a workpiece before processing and a target shape of a workpiece after processing.

The present invention is a workpiece bending method for bending an end portion (for example, a later-described flange WF) of a workpiece (for example, a later-described flange WF) by a processing tool (for example, a later-described processing roller 10). Obtaining a pre-processing angle of the end portion before processing (for example, a pre-processing angle θ ₀ described later) and an end length of a bent portion of the end portion (for example, a flange length L described later), and the processing A trajectory determining step for determining a trajectory (for example, a path to be described later) of the processing tool based on a front angle and a target angle after the processing (for example, a target angle Ψ described later) and the end length, and the trajectory determination And a processing step of bending the end to the target angle by moving the processing tool in a predetermined direction based on the trajectory determined in the process.

  Thereby, since the locus of the processing tool can be appropriately determined based on the pre-machining angle and the target angle, the man-hours necessary for setting the locus of the processing tool in the teaching work can be effectively reduced. Even when the operator has little experience, an appropriate trajectory is set, so that the machining process can be stabilized.

In the trajectory determination step, a difference between the pre-processing angle and the target angle (for example, θ ₀ −Ψ described later) or a value obtained by dividing the difference by the end length (for example, (θ ₀ −Ψ) / described later). L) or both of them are calculated as trajectory determination values, and the trajectory number indicating the number of times of bending from the pre-processing angle to the target angle in a stepwise manner is determined stepwise according to the size of the trajectory determination value. Based on a determination map (for example, a trajectory number determination map shown in FIG. 8 to be described later) and the calculated trajectory determination value, the number of bendings (for example, the number of passes to be described later) and bending angles at each stage (for example, processing to be described later) It is preferable to calculate the midway angle θn).

  Thereby, the number of bendings can be automatically and appropriately calculated by reflecting the processing difficulty level by the difference between the pre-processing angle and the target angle.

  When the shape of the end portion of the workpiece (for example, a workpiece Wb described later) differs in the moving direction of the processing tool, in the trajectory determining step, a first cross section of the end portion viewed in the moving direction of the processing tool ( A second cross section different from the first cross section of the end portion viewed in the moving direction of the processing tool, and the pre-processing angle, the target angle, and the end length of No. 1 in FIG. It is preferable to determine the locus of the processing tool based on the pre-processing angle, the target angle, and the end length of No. 2 to 15 in FIG.

  Thereby, even if the cross-sectional shape is different, the locus of the processing tool can be determined in consideration of the difference in shape.

A difference between the pre-processing angle of the first cross section and the target angle (for example, θ ₀ -Ψ described later) or a value obtained by dividing the difference by the end length (for example, (θ ₀ -Ψ) described later / L) or both are calculated as the first trajectory determination value, and the difference between the pre-processing angle of the second cross section and the target angle (for example, θ ₀ -Ψ described later) or the difference is the end length. Calculated as a second trajectory determination value based on a value divided by (for example, (θ ₀ −Ψ) / L described later) or both, and the number of times of bending in a stepwise manner from the pre-processing angle to the target angle is calculated. The trajectory number determination map (the trajectory number determination map shown in FIG. 13) in which the number of trajectories shown is determined stepwise according to the magnitude of the trajectory determination value, the calculated first trajectory determination value, and the second trajectory. Determine the number of folds and the fold angle at each stage from the determined value. It is preferable to leave.

  Thereby, even if it is a case where a cross section changes with a moving direction, the frequency | count of bending can be calculated automatically and appropriately reflecting a processing difficulty.

  In the trajectory number determination map, a value for determining an upper limit value (for example, 7.0 in one path in the trajectory number determination map described later or 12.0 in two paths or 19.0 in three paths) is determined for each trajectory number. And a bias (for example, described later) with respect to the upper limit value in a range (for example, a 1-pass range, 2-pass range, or 3-pass range described later) to which the track determination value plotted in the track number determination map belongs. It is preferable to calculate the bending angle at each stage reflecting the margin Mα or the margin Mβ).

  Thereby, the processing difficulty in the case where the shape of a cross section differs can be averaged appropriately, and the bending process of a workpiece | work can be performed more stably.

Further, the present invention provides a workpiece bending apparatus (for example, bending a workpiece (for example, a workpiece W, which will be described later)) (for example, a flange WF, which will be described later) with a processing tool (for example, a processing roller 10 described later). For example, in a roller hemming device 1 described later, a pre-processing angle of the end portion before processing (for example, a pre-processing angle θ ₀ described later) and an end length of a bent portion of the end portion (for example, a flange described later) Length L), and the trajectory of the processing tool (for example, a path described later) based on the pre-processing angle and the target angle after processing (for example, target angle Ψ described later) and the end length. A control unit (for example, a control unit 50 to be described later) to be determined and a robot (for example, to be described later) that moves the processing tool in a predetermined direction based on the locus determined by the control unit and bends the end to the target angle. Robot 0) and relates to workpiece bending apparatus comprising a.

  Thereby, since the locus of the processing tool can be appropriately determined based on the pre-machining angle and the target angle, the man-hours necessary for setting the locus of the processing tool in the teaching work can be effectively reduced. Even when the operator has little experience, an appropriate trajectory is set, so that the machining process can be stabilized.

The control unit is configured such that a difference between the pre-processing angle and the target angle (for example, θ ₀ −Ψ described later) or a value obtained by dividing the difference by the end length (for example, (θ ₀ −Ψ) / L described later). ) Or both are calculated as trajectory determination values, and the trajectory number is determined such that the trajectory number indicating the number of times of bending from the pre-processing angle to the target angle is determined stepwise according to the size of the trajectory determination value. From the map (for example, a trajectory number determination map shown in FIG. 6 to be described later) and the calculated trajectory determination value, the number of bendings (for example, the number of passes to be described later) and the bending angle at each stage (for example, to be described later during processing) It is preferable to calculate the angle θn).

  Thereby, the number of bendings can be automatically and appropriately calculated by reflecting the processing difficulty level by the difference between the pre-processing angle and the target angle.

  When the shape of the end of the workpiece (for example, a workpiece Wb described later) is different in the movement direction of the processing tool, the control unit determines the end of the end viewed in the movement direction of the processing tool in the trajectory determination step. The pre-processing angle of the first cross section, the target angle and the end length, and the pre-processing angle of the second cross section different from the first cross section of the end viewed in the moving direction of the processing tool, It is preferable to determine a locus of the processing tool based on a target angle and the end length.

  Thereby, even if the cross-sectional shape is different, the locus of the processing tool can be determined in consideration of the difference in shape.

A difference between the pre-processing angle of the first cross section and the target angle (for example, θ ₀ -Ψ described later) or a value obtained by dividing the difference by the end length (for example, (θ ₀ -Ψ) described later / L) or both are calculated as the first trajectory determination value, and the difference between the pre-processing angle of the second cross section and the target angle (for example, θ ₀ -Ψ described later) or the difference is the end length. Calculated as a second trajectory determination value based on a value divided by (for example, (θ ₀ −Ψ) / L described later) or both, and the number of times of bending in a stepwise manner from the pre-processing angle to the target angle is calculated. The trajectory number determination map (the trajectory number determination map shown in FIG. 13) in which the number of trajectories shown is determined stepwise according to the magnitude of the trajectory determination value, the calculated first trajectory determination value, and the second trajectory. Determine the number of folds and the fold angle at each stage from the determined value. It is preferable to leave.

  Thereby, even if it is a case where a cross section changes with a moving direction, the frequency | count of bending can be calculated automatically and appropriately reflecting a processing difficulty.

  In the trajectory number determination map, a value for determining an upper limit value (for example, 7.0 in one path in the trajectory number determination map described later or 12.0 in two paths or 19.0 in three paths) is determined for each trajectory number. And a bias (for example, described later) with respect to the upper limit value in a range (for example, a 1-pass range, 2-pass range, or 3-pass range described later) to which the track determination value plotted in the track number determination map belongs. It is preferable to calculate the bending angle at each stage reflecting the margin Mα or the margin Mβ).

  Thereby, the processing difficulty in the case where the shape of a cross section differs can be averaged appropriately, and the bending process of a workpiece | work can be performed more stably.

  ADVANTAGE OF THE INVENTION According to this invention, the workpiece | work bending method and workpiece | work bending apparatus which can set the locus | trajectory of a processing tool appropriately based on the shape of the workpiece | work before a process and the target workpiece | work after a process can be provided.

It is a figure showing the schematic structure of roller hemming device 1 concerning one embodiment of the present invention. It is sectional drawing which shows typically the state which mounted the outer panel W1 and the inner panel W2 in the table part 32 before the preliminary | backup process of this embodiment. It is sectional drawing which shows the outer panel W1 and the inner panel W2 of the state by which the flange WF was bend | folded to the target angle (PSI) with the process roller 10 at the preliminary process of this embodiment. It is sectional drawing which shows the outer panel W1 and the inner panel W2 which were bend | folded by the predetermined process at this process of this embodiment. 3 is a cross-sectional perspective view showing an example of a workpiece Wa having the same cross-sectional shape in the moving direction of the processing roller 10. FIG. It is a flow which shows the flow of the movement control of the processing roller 10 when the cross-sectional shape of the workpiece | work W is the same in the moving direction of the processing roller 10. FIG. It is a figure explaining the difference in the number of passes of processing roller 10 by processing difficulty. It is a figure which shows the locus | trajectory number determination map which determines the number of path | passes of the processing roller 10 when the cross-sectional shape of the workpiece | work W is the same in the moving direction of the processing roller 10. FIG. It is a figure explaining the difference in the movement control of the processing roller 10 by the flange length L. FIG. 3 is a cross-sectional perspective view showing an example of a workpiece Wb having a different cross-sectional shape in the moving direction of the processing roller 10. FIG. It is a flow which shows the flow of movement control of the processing roller 10 when the cross-sectional shape of the workpiece | work W differs with the moving direction of the processing roller 10. FIG. It is a table | surface which shows the relationship between the cross section of the several places acquired in the range which performs a preliminary | backup process, and a processing difficulty level. It is a figure which shows the locus | trajectory number determination map which determines the path | pass number of the process roller 10 when the cross-sectional shape of the workpiece | work W differs in the moving direction of the process roller 10. FIG.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. First, the whole structure of the roller hemming apparatus 1 to which the plate material processing method of this embodiment is applied will be described. FIG. 1 is a diagram showing a schematic configuration of a roller hemming device 1 according to an embodiment of the present invention.

  As shown in FIG. 1, the roller hemming device 1 of this embodiment includes a processing table 30, a processing roller 10, a robot 40, and a control unit 50.

  The processing table 30 includes a support base 31 installed on the floor surface and a table unit 32 supported by the support base 31. A work W is placed on the table portion 32. The workpiece W is, for example, an automobile door panel or the like, and includes an outer panel W1 and an inner panel W2. In the outer panel W1, the flange WF is bent at approximately 90 ° at the remaining peripheral edge with respect to the portion (main body) where the inner panel W2 is arranged at the center.

  The outer panel W <b> 1 is placed on the table portion 32 in a state where the flange WF stands upright perpendicular to the surface of the table portion 32. On the outer panel W1, the inner panel W2 is disposed so that the flange WF of the outer panel W1 wraps the end portion of the inner panel W2. An adhesive is applied between the outer panel W1 main body and the end of the inner panel W2 and on the folded surface of the flange WF. The adhesive contains a solid material such as glass beads.

  The processing roller 10 performs bending processing (roller hemming processing) on the flange WF of the outer panel W <b> 1 placed on the table portion 32. The processing roller 10 is supported by the arm 42 of the robot 40 so as to be movable in a three-dimensional direction, and is rotatable with respect to the arm 42.

  The robot 40 includes a base 41 fixed to the floor surface and an arm 42 that supports the processing roller 10 so as to be movable in a three-dimensional direction. The robot 40 moves the arm 42 so that the processing roller 10 moves along a predetermined trajectory.

  Next, the flow of bending by the roller hemming device 1 will be described. In the bending process of the present embodiment, a preliminary process of bending the flange WF of the outer panel W1 stepwise to the target angle Ψ, a main process of crimping the flange WF bent to the target angle Ψ and processing into a final bent shape, Is done.

  FIG. 2 is a cross-sectional view schematically showing a state where the outer panel W1 and the inner panel W2 are placed on the table portion 32 before the preliminary process is performed. In FIG. 2, the vicinity of the flange WF of the outer panel W1 is shown.

As shown in FIG. 2, the outer panel W <b> 1 is placed on the surface of the table portion 32 with the flange WF located at the end thereof being bent upward. In the figure, R1 is a portion that becomes the start end of the R-shaped portion that is a bent portion of the flange WF, and R2 indicates a portion that becomes the end of the R-shaped portion. Moreover, L has shown the flange length from R2 to an edge part in the outer panel W1. Next, the inner panel W2 is overlaid on the central portion (main body) of the outer panel W1. The end of the inner panel W2 is housed inside the flange WF of the outer panel W1 body. The thickness of the outer panel W1 and _{T 1,} the thickness of the inner panel W2 When _{T 2,} the thickness of a stack of outer panel W1 and the inner panel W2 at this time can be expressed as _(T 1 + T _2).

  FIG. 3 is a cross-sectional view showing the outer panel W1 and the inner panel W2 in a state where the flange WF is bent to the target angle Ψ by the processing roller 10 in the preliminary process.

  As shown in FIG. 3, the processing roller 10 of the present embodiment has a substantially cylindrical shape that can rotate around a rotation axis C <b> 1, and the processing surface includes a circumferential shape portion 11 and an R shape portion 12. A boundary portion 13 is formed between the circumferential shape portion 11 and the R shape portion 12. The circumferentially shaped portion 11 is provided on the support side of the arm 42 of the robot 40 in the processing roller 10, and the R-shaped portion 12 is on the tip side opposite to the support side of the arm 42 of the robot 40 in the processing roller 10. Provided. 3 indicates the horizontal length from the R-shaped start end R1 of the outer panel W1 to the reference position of the processing roller 10. D indicates the horizontal length from the reference position to the processing position at which the processing roller 10 contacts the flange WF, and indicates the amount by which the processing roller 10 is pushed. Ψ is a target angle Ψ for performing caulking.

  The robot 40 performs preliminary bending according to a preset trajectory. In the preliminary process of this embodiment, preliminary bending is performed a plurality of times stepwise.

  In this embodiment, the height of the processing roller 10 is constant, and the processing intermediate angle θn (= 1, 2, 3,...) That is changed to one time by adjusting the push-in amount D is adjusted. A method of setting the number of times of preliminary bending and the angle of one preliminary bending will be described later.

  The processing roller 10 is pressed against the flange WF by moving the processing roller 10 with respect to the flange WF along a path in which the arm 42 is set parallel to the surface of the table portion 32.

  The caulking process according to this process is performed on the flange WF bent to the target angle Ψ. FIG. 4 is a cross-sectional view showing the outer panel W1 and the inner panel W2 that are bent into a predetermined shape in this step of the present embodiment.

In this step, the flange WF is bent until it comes into contact with the end of the inner panel W2, and the end of the inner panel W2 is sandwiched between the flange WF and the outer panel W1 main body. In the present embodiment, an adhesive is applied between the outer panel W1 main body and the end of the inner panel W2 or on the folded surface of the flange WF, and the solid material contained in the adhesive is between the outer panel W1 and the inner panel W2. The outer panel W1 and the inner panel W2 are strongly coupled. The thickness h obtained by stacking the outer panel W1 on the inner panel W2 can be expressed as (2T ₁ + T ₂ ). In this way, in the caulking process, the flange WF bent to the target angle Ψ by the preliminary process is further pushed in, and the inner panel W2 is sandwiched by the outer panel W1.

  Next, a method for setting the number of machining times and the machining angle in the preliminary process will be described. In the roller hemming device 1 of the present embodiment, machining is performed with different calculation methods when the cross-sectional shape of the workpiece W is the same in the moving direction of the processing roller 10 and when the cross-sectional shape of the work W is different in the moving direction of the processing roller 10. The number of times and the processing angle are set, and movement control of the processing roller 10 is performed.

  First, a case where the cross-sectional shape of the workpiece W is the same in the moving direction of the processing roller 10 will be described. FIG. 5 is a cross-sectional perspective view showing an example of a work Wa (work W) having the same cross-sectional shape in the moving direction of the processing roller 10. FIG. 6 is a flow showing a flow of movement control of the processing roller 10 when the cross-sectional shape of the workpiece W is the same in the moving direction of the processing roller 10. FIG. 7 is a diagram for explaining the difference in the number of passes of the processing roller 10 depending on the processing difficulty level. FIG. 8 is a diagram illustrating a trajectory number determination map for determining the number of passes of the processing roller 10 when the cross-sectional shape of the workpiece W is the same in the moving direction of the processing roller 10. FIG. 9 is a diagram for explaining a difference in movement control of the processing roller 10 depending on the flange length L. FIG.

A workpiece Wa shown in FIG. 5 is a portion corresponding to a side sill of a vehicle door, and a flange WF at an end portion of the workpiece W is bent at a flange length L and a predetermined angle (hereinafter, pre-processing angle θ ₀ ). Is placed on the table section 32.

As illustrated in FIG. 6, the control unit 50 of the roller hemming device 1 acquires the flange length L and the pre-processing angle θ ₀ in the flow of movement control of the processing roller 10 (S101). In the present embodiment, the flange length L and the pre-processing angle θ ₀ are set based on preset data such as design data set in the previous process.

Based on the preset target angle Ψ before caulking, the flange length L and the pre-machining angle θ ₀ acquired in S101, values for analyzing the processing difficulty are calculated from Expression 1 and Expression 2. (S102). (Θ ₀ −Ψ) / L Expression 1
θ ₀ −Ψ Equation 2

The processing difficulty level will be described with reference to FIG. FIG. 7A schematically shows an example of the workpiece W when the pre-machining angle θ ₀ is relatively large, and FIG. 7B shows the case where the pre-machining angle θ ₀ is relatively small. An example of the workpiece W is schematically shown. Incidentally, theta ₂ (b), the theta ₃ and 7 (a) of FIG. 7 is a target angle for performing caulking, it is assumed that substantially the same angle.

When the pre-machining angle θ ₀ is large and the machining difficulty is high, the number of passes is set large, and when the pre-machining angle θ ₀ is small and the machining difficulty is low, the number of passes is set small. For example, in FIG. 7A where the pre-processing angle θ ₀ is large, the preliminary process is performed three times, and in FIG. 7B where the pre-processing angle θ _{0 is} small, the preliminary process is performed twice. .

As shown in FIG. 8, the range for determining the number of paths based on the value of (θ ₀ −Ψ) / L calculated in S102 and the number of paths based on the value of (θ ₀ −Ψ) are determined. And a range to be set in advance.

In the present embodiment, the range for determining the number of paths based on the value of (θ ₀ -Ψ) / L is a 1-pass is less than 7.0 the value of _{(θ 0 -Ψ) / L,} 7 .0 or more and less than 12.0 is 2 passes, and 12.0 or more is 3 passes. On the other hand, the range for determining the number of paths based on the value of θ ₀ -Ψ is one path is less than the value of θ ₀ -Ψ is 10 deg, a two-pass is less than 60 degrees or more 10 deg, the above 60deg is There are 3 passes.

In the step of determining the number of paths, the number of paths is calculated based on the value calculated by (θ ₀ −Ψ) / L expression 1, and the number of paths is calculated based on the value calculated by θ ₀ −Ψ expression 2. calculate. Then, the number of passes based on the value of (θ ₀ −Ψ) / L expression 1 and the number of paths based on the value of θ ₀ −Ψ expression 2 are compared, and the higher processing difficulty is determined as the number of passes in the preliminary process. Determine as.

The determination of the number of passes will be described by substituting specific numerical values into Equation 1 and Equation 2. When the workpiece W shown in FIG. 5 has a pre-machining angle θ ₀ = 98.17 deg, a flange length L = 7.57 (mm), and a target angle Ψ = 30 deg, the following results are obtained. Become.
(Θ ₀ −Ψ) /L=9.00
θ ₀ −Ψ = 68.17

(Θ ₀ −Ψ) /L=9.00 is a range from 7.0 to less than 12.0 in which two paths are set, and the number of paths is two. Since θ ₀ −Ψ = 68.17 deg is 60 deg or more in which three paths are set, the number of paths is three. Since the higher processing difficulty is given priority, in this case, the number of passes is set to 3.

  When the number of passes is determined, a machining intermediate angle θn set for each pass is calculated (S104). When the cross-sectional shape of the workpiece W is the same in the moving direction of the processing roller 10, the processing intermediate angle θn is set to an angle obtained by subtracting the target angle Ψ from the pre-processing angle θ0 by the number of passes. In the above example, θ0 = 98.17 deg, θ1 = 75.4 deg, θ2 = 52.7 deg, θ3 = 30 deg (= target angle Ψ) is set as the machining intermediate angle θn.

  Next, an intermediate cross section is created on the CAD based on θ0 (S105), and the pushing amount D1 → n of the processing roller 10 is calculated based on the intermediate cross section (S106).

  In the present embodiment, the bending process is performed without changing the height of the processing roller 10. The difference in the movement control of the processing roller 10 depending on the flange length L will be described with reference to FIG. 9A shows a case where the flange length L is relatively long, and FIG. 9B shows a case where the flange length L is relatively short.

  As shown in FIG. 9A, when the flange length L is relatively long, the R-shaped portion 12 of the processing roller 10 is brought into surface contact with the outer surface of the flange WF. As shown in FIG. 9B, when the flange length L is relatively short, the circumferentially shaped portion 11 of the processing roller 10 is brought into line contact with the end face of the flange WF.

  The push-in amount D set for each pass is set for each machining intermediate angle set for each pass. For example, in the above example in which θ0 = 98.17 deg, θ1 = 75.4 deg, θ2 = 52.7 deg, and θ3 = 30 deg are set, the push amount D1 = 4.6 mm is set in the first bending process. In the second bending process, an indentation amount D2 = 7.8 mm is set, and in the third bending process, an indentation amount D3 = 10.4 mm is set.

  When the pushing amount is set for each pass, the position of the processing roller 10 of the roller hemming device 1 is controlled by the arm 42 of the robot 40, and the actual bending work is performed. The roller hemming device 1 performs caulking on the workpiece W bent to the target angle ψ in the preliminary process.

According to the workpiece bending method and the roller hemming device 1 of the embodiment described above, the following effects are obtained.
A workpiece bending method in which bending is performed on the flange WF of the workpiece Wa by the processing roller 10, and a process of obtaining a pre-processing angle θ ₀ of the flange WF before processing and a flange length L of a bent portion of the flange WF. And a path determination step for determining the path (trajectory) of the processing roller 10 based on the pre-processing angle θ _{0, the} post-processing target angle Ψ, and the flange length L, and the path determined in the path determination step. Based on the processing step of moving the processing roller 10 in a predetermined direction and bending the flange WF to the target angle Ψ.

Thereby, since the path of the processing roller 10 can be appropriately determined based on the pre-processing angle θ ₀ and the target angle Ψ, the man-hours necessary for setting the path of the processing roller 10 in the teaching work can be effectively reduced. Even when the operator has little experience, an appropriate trajectory is set, so that the machining process can be stabilized.

In the locus determination step, both the difference (θ ₀ −Ψ) between the pre-machining angle θ ₀ and the target angle Ψ and the value obtained by dividing the difference by the flange length L ((θ ₀ −Ψ) / L) are determined as the locus determination value. A trajectory number determination map (see FIG. 8) in which the number of passes indicating the number of times of bending to be calculated and bent stepwise from the pre-machining angle θ ₀ to the target angle Ψ is determined stepwise according to the size of the trajectory determination value. Based on the determined trajectory value, the number of passes and the machining intermediate angle θn at each stage are calculated.

As a result, the number of bendings can be automatically and appropriately calculated by reflecting the processing difficulty level by the difference between the pre-processing angle θ ₀ and the target angle Ψ.

  Next, FIG. 10 for explaining the case where the cross-sectional shape of the work W is different in the moving direction of the processing roller 10 is a cross-sectional perspective view showing an example of a work Wb (work W) having a different cross-sectional shape in the moving direction of the processing roller 10. is there. FIG. 11 is a flow showing a flow of movement control of the processing roller 10 when the cross-sectional shape of the workpiece W is different in the moving direction of the processing roller 10. FIG. 12 is a table showing the relationship between the cross-sections at a plurality of locations acquired within the scope of the preliminary process and the processing difficulty level. FIG. 13 is a diagram illustrating a trajectory number determination map for determining the number of passes of the processing roller 10 when the cross-sectional shape of the workpiece W is different in the moving direction of the processing roller 10.

  A workpiece Wb shown in FIG. 10 is a rear side portion of the vehicle door, and a flange WF at an end portion of the workpiece W has a curved surface. The cross-sectional shape is different in the moving direction of the processing roller 10.

  As shown in FIG. 11, first, a plurality (N) of cross sections at different positions in the moving direction are acquired, and cross section information for each is created (S201). In the present embodiment, the cross-sectional shape is acquired at a predetermined interval, for example, about a few mm pitch based on preset data such as design data set in the previous process. In the example shown in FIG. 12, 15 cross sections are created. In addition, how many cross sections are created can employ | adopt appropriate methods, such as setting based on the range which performs a preliminary process, or the shape of a cross section, for example.

Next, the flange length L of each cross section and the pre-processing angle θ ₀ are acquired based on the cross section acquired in S201 (S202). Next, the values of (θ ₀ −Ψ) / L and (θ ₀ −Ψ) are calculated for each cross section. In the example shown in FIG. 12, (θ ₀ −Ψ) / L and (θ ₀ −Ψ) are calculated for each of the 15 cross sections.

Among the values of (θ ₀ -Ψ) / L of each cross section, the highest value of (θ ₀ -Ψ) / L is acquired, and the highest value of θ ₀ -Ψ is acquired. In the example shown in FIG. 12, the highest value of (θ ₀ −Ψ) / L is 17.79, and the highest value of θ ₀ −Ψ is 62.61. The number of passes is determined by the same method as in the case where the cross-sectional shape of the workpiece W is the same in the moving direction of the processing roller 10.

In this embodiment, as shown in locus number determination map in FIG. 13, the range for determining the number of paths based on the value of (θ ₀ -Ψ) / L is the (θ ₀ -Ψ) / L If the value is less than 7.0, there is one pass, 7.0 or more and less than 12.0, two passes, and 12.0 or more and less than 19.0, there are three passes. On the other hand, the range for determining the number of paths based on the value of θ ₀ -Ψ is one path is less than the value of θ ₀ -Ψ is 10 deg, a two-pass is less than 60 degrees or more 10 deg, 60 deg or 110deg Less than 3 passes. In the example shown in FIG. 12, since the highest value of (θ ₀ −Ψ) / L is 17.79, there are 3 paths, and the highest value of θ ₀ −Ψ is 62.61 degrees, so there are 3 paths.

The number of passes set based on the highest value of (θ ₀ −Ψ) / L is compared with the number of passes set based on the highest value of θ ₀ −Ψ, and the degree of processing difficulty is higher The number of passes is determined. In the example shown in FIG. 12, since there are three paths, the number of paths is set to three.

When the number of passes is determined in the process of S204, the process proceeds to a process of calculating a machining intermediate angle (S205). In the present embodiment, in the calculation of the machining intermediate angle in S205, the highest value among the values of (θ ₀ −Ψ) / L is acquired and the value of θ ₀ −Ψ is obtained as in the determination of the number of S204 passes. Get the highest value of. For the highest value of (θ ₀ -Ψ) / L and the highest value of θ ₀ -Ψ, the machining intermediate angle and the push-in amount in the subsequent processing are set.

A method for calculating the midway angle will be described. The processing intermediate angle θ1α is acquired based on the number of passes determined by the value of (θ ₀ −Ψ) / L, and the processing intermediate angle θ1β is acquired based on the number of passes determined by the value of (θ ₀ −Ψ). . The machining intermediate angles θ1α and θ1β are obtained by dividing the angle obtained by subtracting the target angle ψ from the pre-machining angle θ0 by the number of passes.

In the example of FIG. 13 is a pre-processing angle θn = 92.61, and a target angle Ψ = 30 deg. In this case, for the (θ ₀ -Ψ) / L, during processing angle θ1α = 71.74deg, θ2α = 50.87deg, θ3α = 30deg next, for the θ ₀ -Ψ Since the number of paths is the same, during processing angle θ1β = 71.74 deg, θ2β = 50.87 deg, and θ3β = 30 deg.

Further, the deviation of the value of (θ ₀ −Ψ) / L within the setting range is calculated as the margin Mα. The margin Mα is a dimensionless number calculated based on the upper limit side of the setting range. The margin Mα is set based on a numerical value that determines an upper limit for determining the number of paths in the setting range, a numerical value that has the highest (θ ₀ −Ψ) / L, and a numerical value that determines the lower limit. The margin Mα indicates how far the numerical value that determines the number of passes is away from the numerical value that determines the upper limit. In the above example, Mα = (19-17.79) / (19-12), and Mα = 0.17.

Similarly, the deviation of the value of θ ₀ −Ψ within the setting range is calculated as the margin Mβ. The margin Mβ is calculated based on the upper limit side of the setting range. The margin Mβ is set based on a numerical value that determines an upper limit for determining the number of paths in the setting range, a numerical value that has the highest θ ₀ −Ψ, and a numerical value that determines the lower limit. The margin Mβ indicates how far the numerical value that determines the number of passes is away from the numerical value that determines the upper limit. In the above example, Mβ = (110−61.92) / (110−60), and Mβ = 0.95.

  An intermediate machining angle θn is calculated based on the intermediate machining angle θ1α, the intermediate machining angle θ1β, the margin Mα, and the margin Mβ. As shown in FIG. 13, θn = 1 / (Mα + Mβ) × (Mβθnα + Mαθnβ) Equation 3 calculates the midway angle of machining. If the equation 3 of θn = 1 / (Mα + Mβ) × (Mβθnα + Mαθnβ) is applied to the example of FIG.

  Next, an intermediate cross section is created on CAD based on the largest angle θ0 among the cross sections θ0 (S206). In the example of FIG. 12, θ0 = 92.61 deg is used. Based on the intermediate section set in S206, the push amount D1 → n of the processing roller 10 is calculated (S207). The push-in amount D set for each pass is set for each machining intermediate angle set for each pass. The calculation of the push amount D is the same as in the above embodiment. In the example of FIG. 12, the pushing amount D1 = 2.9 mm is set in the first bending process, the pushing amount D2 = 4.3 mm is set in the second bending process, and the pushing amount is set in the third bending process. D3 = 5.4 mm is set. Data drawn in each cross section is output, and the flow ends (S208).

According to the bending method and the roller hemming device 1 of the embodiment described above, the following effects can be obtained.
When the shape of the workpiece Wb differs in the moving direction of the processing roller 10, in the trajectory determination step, the pre-processing angle θ ₀ , the target angle Ψ, and the flange length L of the first cross section of the flange WF viewed in the moving direction of the processing roller 10. And the locus of the processing roller 10 based on the pre-processing angle θ ₀ , the target angle ψ, and the flange length L of the second cross section different from the first cross section of the flange WF viewed in the moving direction of the processing roller 10. decide.

  Thereby, even if it is a case where the shape of a cross section differs, the locus | trajectory of the processing roller 10 can be determined in consideration of the difference in shape.

Both the difference (θ ₀ −Ψ) between the pre-processing angle θ ₀ and the target angle Ψ of the first cross section and the value obtained by dividing the difference by the flange length L ((θ ₀ −Ψ) / L) are the first trajectory. Calculate as the decision value. Further, based on both the difference (θ ₀ −Ψ) between the pre-processing angle θ ₀ and the target angle Ψ of the second cross section and the value obtained by dividing the difference by the flange length L ((θ ₀ −Ψ) / L). Calculated as the second locus determination value. In addition, a trajectory number determination map (see FIG. 13) in which the number of passes indicating the number of times of bending in a stepwise manner from the pre-machining angle θ ₀ to the target angle Ψ is determined stepwise according to the size of the trajectory determination value; The number of passes and the bending angle at each stage are calculated from the calculated first locus determination value and second locus determination value.

  Thereby, even if it is a case where a cross section changes with a moving direction, the frequency | count of bending can be calculated automatically and appropriately reflecting a processing difficulty.

  In the trajectory number determination map, a value for determining an upper limit value (7.0 in 1 pass, 12.0 in 2 passes, 19.0 in 3 passes) is determined for each path, and is plotted in the trajectory number determination map. The bending angle at each stage is calculated by reflecting the margin Mα or the margin Mβ with respect to the upper limit value in the range to which the locus determination value belongs (1 pass range, 2 pass range, or 3 pass range).

  Thereby, the processing difficulty in the case where the shape of a cross section differs can be averaged appropriately, and the bending process of a workpiece | work can be performed more stably.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not restrict | limited to the above-mentioned embodiment, It can change suitably. For example, it is not limited to the shape of the processing roller of the above-described embodiment, and can be appropriately changed as long as it can be bent. Further, the trajectory number determination map is not limited to that described in the above embodiment, and the trajectory number indicating the number of times of bending to be performed stepwise from the pre-processing angle to the target angle is stepwise according to the size of the trajectory determination value. The table format may be determined. Thus, the trajectory number determination map can be changed as appropriate according to circumstances.

1 Roller hemming device (work bending machine)
10 Processing roller (processing tool)
40 Robot 50 Control part W Work WF Flange θ ₀ Pre-machining angle θn Machining angle Ψ Target angle

Claims (10)

A workpiece bending method for bending an end of a workpiece with a processing tool,
Obtaining a pre-processing angle of the end before processing and an end length of a bent portion of the end; and
A trajectory determination step for determining a trajectory of the processing tool based on the pre-processing angle and the target angle after processing, and the end length;
A processing step of moving the processing tool in a predetermined direction based on the trajectory determined in the trajectory determination step, and bending the end portion to the target angle;
Bending method including workpiece. In the locus determination step,
A difference between the pre-processing angle and the target angle or a value obtained by dividing the difference by the end length or both are calculated as a locus determination value,
From the trajectory number determination map in which the trajectory number indicating the number of times of bending to be bent stepwise from the pre-processing angle to the target angle is determined stepwise according to the size of the trajectory determination value, and the calculated trajectory determination value The work bending method according to claim 1, wherein the number of bending times and the bending angle at each stage are calculated. In the trajectory determination step when the shape of the end of the workpiece is different in the moving direction of the processing tool,
The pre-processing angle, the target angle, and the end length of the first cross section of the end viewed in the moving direction of the processing tool;
The pre-processing angle, the target angle and the end length of a second cross section different from the first cross section of the end viewed in the moving direction of the processing tool;
The workpiece bending method according to claim 1, wherein a trajectory of the processing tool is determined based on the method. A difference between the pre-processing angle of the first cross section and the target angle or a value obtained by dividing the difference by the end length or both are calculated as a first locus determination value,
A difference between the pre-processing angle of the second cross section and the target angle or a value obtained by dividing the difference by the end length or both as the second locus determination value,
A trajectory number determination map in which a trajectory number indicating the number of times of bending to be bent stepwise from the pre-processing angle to the target angle is determined stepwise according to the size of the trajectory determination value, a calculated first trajectory determination value, and The work bending method according to claim 3, wherein the number of bendings and the bending angle at each stage are calculated from the second locus determination value. In the trajectory number determination map, a value for determining an upper limit value is determined for each trajectory number,
5. The workpiece bending method according to claim 4, wherein a bending angle at each stage is calculated by reflecting a deviation with respect to the upper limit value in a range to which a locus determination value plotted in the locus number determination map belongs. A workpiece bending apparatus that performs bending on an end of a workpiece with a processing tool,
The pre-processing angle of the end before processing and the end length of the bent portion of the end are acquired, and the trajectory of the processing tool is obtained based on the pre-processing angle, the target angle after processing, and the end length. A control unit to determine;
A robot that moves the processing tool in a predetermined direction based on the trajectory determined by the control unit and bends the end to the target angle;
A workpiece bending apparatus comprising: The controller is
A difference between the pre-processing angle and the target angle or a value obtained by dividing the difference by the end length or both are calculated as a locus determination value,
From the trajectory number determination map in which the trajectory number indicating the number of times of bending to be bent stepwise from the pre-processing angle to the target angle is determined stepwise according to the size of the trajectory determination value, and the calculated trajectory determination value The work bending apparatus according to claim 6, wherein the number of bending times and a bending angle at each stage are calculated. The controller is
In the case where the shape of the end portion of the workpiece is different in the moving direction of the processing tool,
The pre-processing angle, the target angle, and the end length of the first cross section of the end viewed in the moving direction of the processing tool;
The pre-processing angle, the target angle and the end length of a second cross section different from the first cross section of the end viewed in the moving direction of the processing tool;
The workpiece bending apparatus according to claim 6, wherein a trajectory of the processing tool is determined based on the workpiece. A difference between the pre-processing angle of the first cross section and the target angle or a value obtained by dividing the difference by the end length or both are calculated as a first locus determination value,
A difference between the pre-processing angle of the second cross section and the target angle or a value obtained by dividing the difference by the end length or both as the second locus determination value,
A trajectory number determination map in which a trajectory number indicating the number of times of bending to be bent stepwise from the pre-processing angle to the target angle is determined stepwise according to the size of the trajectory determination value, a calculated first trajectory determination value, and The workpiece bending apparatus according to claim 8, wherein the number of bendings and a bending angle at each stage are calculated from the second locus determination value. In the trajectory number determination map, a value for determining an upper limit value is determined for each trajectory number,
10. The workpiece bending apparatus according to claim 9, wherein a bending angle at each stage is calculated by reflecting a deviation from the upper limit value in a range to which a locus determination value plotted in the locus number determination map belongs.

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