JP2010162558A - Bending machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the accuracy in the bending work of a workpiece W while shortening a period of time required for positioning the workpiece W. <P>SOLUTION: The bending machine includes: a L-axis controlling motor controlling means 53 for controlling an L-axis motor 21 on the basis of a target L-value so that the striking surfaces 49a of a striking members 49 are situated in a predetermined position in the L-axis direction; a deflection quantity calculating means 61 for calculating the deflection quantity in the L-axis direction of a stretch 37 on the basis of the pressing force of the workpiece W to the striking surface 49a of the striking member 49; and a target L-value correcting means 65 for correcting the target L-value on the basis of the deflection quantity in the L-axis direction of the stretch 37. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a bending machine for bending a plate-shaped workpiece by cooperation of a punch die and a die die.

  Various researches and developments have been made on bending machines, and the prior art of bending machines includes those shown in Patent Document 1 and Patent Document 2.

  That is, a lower table extending in the Y-axis direction is provided at the lower part of the main body frame, and the lower table is provided with a die mold on the upper side in a detachable manner. Further, an upper table extending in the Y-axis direction is provided on the upper part of the main body frame so as to face the lower table vertically, and the upper table can be moved up and down relatively with respect to the lower table, A punch die is detachably provided on the lower side.

  The main body frame is provided with a pair of L-axis supporters extending in the L-axis direction (front-rear direction) and spaced apart in the Y-axis direction (left-right direction). Between the pair of L-axis supporters, the Y-axis direction is provided. A stretch extending to is installed, and this stretch is movable in the L-axis direction. In addition, L-axis servomotors that move the stretch in the L-axis direction are provided at the rear ends of the pair of L-axis supporters. Further, the stretch is provided with a plurality of abutting members, and each abutting member has an abutting surface capable of abutting the end surface (rear end surface) of the plate-like workpiece.

  The bending machine includes an NC control device, and the NC control device includes a memory that stores a machining program, mold information, and the like, and a CPU that interprets and executes the machining program. In addition, the CPU of the NC control device functions as an L-axis motor control unit that controls the L-axis servo motor based on the target L value so that the abutting surface of the abutting member is located at a predetermined position in the L-axis direction. Have.

  Therefore, the CPU (L-axis motor control unit) of the NC control device controls the L-axis servo motor based on the target L value to move the stretch in the L-axis direction, and the abutting surfaces of the plurality of abutting members are set to L. It is located at a predetermined position in the axial direction. Subsequently, the workpiece is positioned in the L-axis direction with respect to the die (die die, punch die) by abutting the end surface of the workpiece against the abutting surfaces of the plurality of abutting members. Then, by lowering the upper table relative to the lower table (in other words, lowering the lower tail portion relative to the upper table), the punch die is brought into contact with the workpiece, and the punch metal The workpiece can be bent by the cooperation of the die and the die die.

JP 2007-69243 A JP-A-7-32047

  By the way, in order to improve the work bending accuracy (work bending flange accuracy), the rigidity of the stretch or the like is increased, and the work pressing force against the abutting surfaces of a plurality of abutting members (the worker's work It is necessary to suppress deformation such as stretching (including bending in the L-axis direction of the stretch) due to the pressing force) and increase the positioning accuracy of the workpiece with respect to the mold. On the other hand, when the rigidity of the stretch or the like is increased, there is a problem that the moving speed of the stretch or the like is slowed due to an increase in the weight of the stretch or the like, and the time required for positioning the workpiece becomes long.

  That is, there is a problem that it is not easy to improve the accuracy of bending of the workpiece while shortening the time required for positioning the workpiece.

  Then, an object of this invention is to provide the bending machine of a novel structure which can solve the above-mentioned problem.

A first feature of the present invention (feature of the invention described in claim 1) is a bending machine for bending a plate-like workpiece by cooperation of a punch die and a die die.
A lower table provided in a lower part of the main body frame, detachably provided on the upper side and extending in the Y-axis direction;
The upper part of the main body frame is provided on the lower table so as to be opposed to the lower table, and can be moved up and down relatively with respect to the lower table. An extended upper table,
A pair of L-axis supporters provided in the body frame or the lower table so as to be spaced apart in the Y-axis direction and extending in the L-axis direction;
Stretched between the pair of L-axis supporters, movable in the L-axis direction, and extended in the Y-axis direction;
An L-axis control motor for moving the stretch in the L-axis direction;
An abutting member provided on the stretch and having an abutting surface capable of butting the end surface of the workpiece;
L-axis motor control means for controlling the L-axis control motor based on a target L value (target L value of the abutting member) so that the abutting surface of the abutting member is located at a predetermined position in the L-axis direction. When,
A deflection amount calculating means for calculating a deflection amount of the stretch in the L-axis direction based on a pressing force of the workpiece against the abutting surface of the abutting member (pressing force of the worker's workpiece);
The gist of the present invention is to include target L value correction means for correcting the target L value based on the amount of bending of the stretch in the L-axis direction.

  In the claims and specification of the present application, “provided” means not only directly provided but also indirectly provided via an interposed member such as a bracket. is there.

  According to the first feature, the L-axis motor control means controls the L-axis control motor based on a target L value to move the stretch in the L-axis direction, so that the abutting surface of the abutting member is moved. It is located at a predetermined position in the L-axis direction. Subsequently, the workpiece is positioned in the L-axis direction with respect to the die (the die die, the punch die) by abutting the end surface of the workpiece against the abutting surface of the abutting member. Then, the punch die is brought into contact with the workpiece by lowering the upper table relative to the lower table (in other words, raising the lower tail portion relative to the upper table). In other words (in other words, the punch die reaches the pinching point), the workpiece can be bent by the cooperation of the punch die and the die die.

  Here, the pressing force of the workpiece against the abutting surface of the abutting member by the deflection amount calculating means until the punch die comes into contact with the workpiece after the lowering of the upper table is started. The amount of bending of the stretch in the L-axis direction is calculated based on the above. Subsequently, the target L value is corrected by the target L value correcting means based on the deflection amount of the stretch in the L axis direction, and the L axis control motor is corrected based on the corrected target L value by the L axis motor control means. To control. Accordingly, the abutting position of the workpiece can be corrected according to the pressing force of the workpiece against the abutting surface of the abutting member until immediately before the workpiece bending process is started.

A second feature of the present invention (a feature of the invention described in claim 2) includes, in addition to the first feature, movable struts provided on each L-axis supporter so as to be movable in the L-axis direction. ,
The gist of the stretch is that it is constructed between the pair of L-axis supporters via the pair of movable struts.

According to a third feature of the present invention (a feature of the invention described in claim 3), in addition to the second feature, the L of the movable column is based on the pressing force of the workpiece against the abutting surface of the abutting member. A tilt amount calculating means for calculating the tilt amount in the axial direction,
The gist of the target L value correcting means is to correct the target L value based on the amount of bending of the stretch in the L-axis direction and the amount of tilting of the movable column in the L-axis direction.

  According to the third feature, in addition to the operation according to the second feature, the amount of tilting of the movable column in the L-axis direction based on the pressing force of the workpiece against the abutting surface of the abutting member by the amount-of-falling calculating means. And the target L value is corrected by the target L value correcting means based on the amount of bending of the stretch in the L-axis direction and the amount of tilting of the movable column in the L-axis direction.

  A fourth feature of the present invention (a feature of the invention described in claim 4) is a change in the current value of the L-axis control motor in addition to any one of the first to third features. The gist of the invention is that it comprises pressing force calculation means for calculating the pressing force of the workpiece against the abutting surface of the abutting member based on the amount.

  According to the present invention, the work abutting position can be corrected according to the pressing force of the work against the abutting surface of the abutting member until just before the work bending process is started. Even if the rigidity is not increased, the workpiece can be positioned with high accuracy with respect to the mold. Therefore, it is possible to improve the accuracy of bending of the workpiece while reducing the time required for positioning the workpiece by increasing the moving speed of the stretch or the like by reducing the weight of the stretch or the like.

1 is a perspective view of a bending machine according to an embodiment of the present invention. It is a perspective view of the principal part of the bending machine which concerns on embodiment of this invention. It is sectional drawing along the III-III line in FIG. It is a control block diagram concerning the embodiment of the present invention. It is a flowchart explaining the operation | movement of a bending process. It is a figure explaining the bending amount etc. of the L-axis direction of a stretch.

  An embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 1, a bending machine 1 according to an embodiment of the present invention performs bending on a plate-like workpiece W by cooperation of a punch die 3 and a die die 5, A main body frame 7 is provided as a base. The main body frame 7 includes a pair of side plates 9 facing left and right, a connecting member (not shown) for connecting the pair of side plates 9 and the like.

  A lower table 11 extending in the Y-axis direction (in other words, the left-right direction) is provided at the lower portion of the main body frame 7, and the lower table 11 includes the die mold 5 detachably on the upper side. ing. Further, an upper table 13 extending in the Y-axis direction is provided on the upper part of the main body frame 7 so as to face the lower table 11 in the vertical direction. The upper table 13 can be moved up and down (in other words, in the Z-axis direction). The punch mold 3 is detachably provided on the lower side. And the hydraulic cylinder 15 which raises / lowers the upper table 13 is each provided in the upper part of a pair of side plate 9, The piston rod 15r in each hydraulic cylinder 15 is connected with the appropriate position of the upper table 13. FIG. Here, when an operator steps on a foot switch (not shown), the upper table 13 is lowered by the operation of the pair of hydraulic cylinders 15. Instead of allowing the upper table 13 to be raised and lowered, the lower table 11 may be raised and lowered.

  As shown in FIGS. 1 to 3, a pair of L-axis supporters 17 extending in the L-axis direction (front-rear direction) are provided apart from each other in the Y-axis direction on the rear side of the die mold 5 in the main body frame 7. Each L-axis supporter 17 is provided with an L-axis slider 19 so as to be movable in the L-axis direction. The L-axis supporter 17 may be provided on the rear surface (back surface) of the lower table 11 instead of being provided on the main body frame 7.

  An L-axis servomotor 21 (an example of an L-axis control motor) that moves the L-axis slider 19 in the L-axis direction is provided at the rear end of each L-axis supporter 17. Each L-axis supporter 17 is provided with an L-axis ball screw 23 extending in the L-axis direction and interlockingly connected to the output shaft of the corresponding L-axis servomotor 21. Are provided with nut members 25 screwed into corresponding L-axis ball screws 23.

  Each L-axis slider 19 is provided with a movable support 27 movably in the Z-axis direction via the Z-axis guide 29. In other words, each L-axis supporter 17 has an L corresponding to the movable support 27. A shaft slider 19 is provided so as to be movable in the L-axis direction. Further, a Z-axis servomotor 31 for moving the movable column 27 in the Z-axis direction is provided at the lower end portion of each movable column 27. Each movable column 27 extends in the Z-axis direction and corresponds to the corresponding Z-axis. A Z-axis ball screw 33 interlocked with the output shaft of the servo motor 31 is rotatably provided, and each L-axis slider 19 is provided with a nut member 35 screwed to the corresponding Z-axis ball screw 33. ing.

  A stretch 37 extending in the Y-axis direction is installed on the upper part of the pair of movable struts 27. In other words, the stretch 37 is attached to the pair of L-axis supporters 17 by the pair of L-axis sliders 19 and the pair of movable pieces. It is erected via a support 27. Here, the stretch 37 is movable in the L-axis direction integrally with the pair of L-axis sliders 19 and the like by driving the L-axis servo motor 21, and is driven by the pair of Z-axis servo motors 31. 27 can move in the Z-axis direction integrally.

  The stretch 37 is provided with a pair of Y-axis sliders 39 so as to be movable in the Y-axis direction via a plurality of Y-axis guides 41. A Y-axis servomotor 43 that moves in the direction is provided. Further, a pinion 45 is integrally provided on the output shaft of each Y-axis servomotor 43, and a rack 47 extending in the Y-axis direction and meshing with the pair of pinions 45 is provided on the rear side of the stretch 37. It has been. Each Y-axis slider 39 is provided with an abutting member 49 having an abutting surface 49a against which the end surface of the workpiece W can be abutted. In other words, the stretch 37 has a pair of abutting members. 49 is provided via a pair of Y-axis sliders 39 and a pair of movable columns 27.

  As shown in FIG. 4, the bending machine 1 includes an NC control device 51. The NC control device 51 interprets and executes a processing program, a memory for storing mold information, and the like. CPU. In addition, a pair of L-axis servomotors 21, a pair of Z-axis servomotors 31, and a pair of Y-axis servomotors 43 are electrically connected to the NC controller 51. A function as an L-axis motor control unit 53 that controls the pair of L-axis servomotors 21 based on the target L value so that the abutment surfaces 49a of the plurality of abutment members 49 are positioned at predetermined positions in the L-axis direction, The Z-axis servo motor 31 functions as a Z-axis motor controller 55 and the Y-axis motor controller 57 controls a pair of Y-axis servo motors 43.

  Furthermore, the CPU of the NC control device 51 calculates a pressing force calculation unit that calculates the pressing force of the workpiece W against the abutting surfaces 49a of the pair of abutting members 49 based on the amount of change in the current value of the pair of L-axis servomotors 21. 59, a function as a bending amount calculation unit 61 that calculates the bending amount of the stretch 37 in the L-axis direction based on the pressing force of the work W against the abutting surfaces 49a of the pair of abutting members 49, and each abutting member A function as a tilt amount calculation unit 63 that calculates the tilt amount of each movable support column 27 in the L-axis direction based on the pressing force of the workpiece W against the abutment surface 49a of 49, the deflection amount of the stretch 37 in the L-axis direction, and each movable It has a function as a target L value correction unit 65 that corrects the target L value (target L value of the abutting member 49) based on the tilt amount of the support column 27 in the L-axis direction. Details of these functions are as follows. , It is shown in the contents of the operation of bending of the predicate.

  Next, with reference to FIG. 5 and FIG. 6, the bending operation by the bending machine 1 according to the embodiment of the present invention will be described including the action.

  First, the pair of Z-axis servomotors 31 are controlled in advance by the CPU (Z-axis motor control unit 55) of the NC control device 51 to move the pair of movable support columns 27 in the Z-axis direction. Is positioned at a predetermined position in the Z-axis direction according to the bending height of the workpiece W, and the pair of Y-axis servomotors 43 is controlled by the CPU (Y-axis motor control unit 57) of the NC control device 51. The shaft slider 39 is moved in the Y-axis direction, and the pair of abutting members 49 are positioned at predetermined positions in the Y-axis direction corresponding to the bending width of the workpiece W. Then, the CPU (L-axis motor control unit 53) of the NC control device 51 controls the pair of L-axis servomotors based on the target L value to move the stretch in the L-axis direction. The abutting surface 49a is positioned at a predetermined position in the L-axis direction (step 1 in FIG. 5).

  After step 1, the end surface of the work W is abutted against the abutting surfaces 49a of the pair of abutting members 49, thereby positioning the workpiece W in the L-axis direction with respect to the die (die die 5, punch die 3). (Step 2 in FIG. 5). Then, by stepping on the foot switch, the pair of hydraulic cylinders 15 are operated to start the lowering of the upper table 13 (step 3 in FIG. 5).

After the end of step 3, the work W against the abutment surface 49a of the pair of abutment members 49 based on the amount of change in the current value of the pair of L-axis servomotors 21 by the CPU (pressing force calculation unit 59) of the NC control device 51. Is calculated (step 4 in FIG. 5). Specifically, by the CPU (pressing force calculation unit 59) of the NC control device 51,
P ₁ = f (i ₁ ) ... Equation (1) P ₂ = f (i ₂ ) ... Equation (2) is applied,
The pressing force of the workpiece W against the abutting surface 49a of the pair of abutting members 49 is calculated.

Here, P ₁ : pressing force of the workpiece W against the abutting 49 a of one (left side) abutting member 49, P ₂ : pressing force of the workpiece W against the abutting surface 49 a of the other (right side) abutting member 49, i _{1 is the} amount of change in the current value of one L-axis servomotor 21, i _{2 is the} amount of change in the current value of the other L-axis servomotor 21.

After the end of step 4, the amount of flexure in the L-axis direction of the stretch 37 is determined based on the pressing force of the work W against the abutment surface 49 a of the pair of abutment members 49 by the CPU (deflection amount calculation unit 61) of the NC control device 51. Calculate (step 5 in FIG. 5). Specifically, by the CPU (deflection amount calculation unit 61) of the NC control device 51,
δ = f (P ₁ , P ₂ , MS, L, Y ₁ , Y ₂ ) ... Applying equation (3),
Based on the pressing force of the workpiece W against the abutting surfaces 49a of the pair of abutting members 49, the amount of bending of the stretch 37 in the L-axis direction is calculated.

Where δ is the amount of bending of the stretch 37 in the L-axis direction (see FIG. 6), MS is the section modulus of the stretch 37, L is the length of the stretch 37 in the Y-axis direction, and Y _{1 is} the origin position in the Y-axis direction. The coordinate position in the Y-axis direction of one abutting member 49 as a reference (see FIG. 6), Y ₂ : The coordinate position in the Y-axis direction of the other abutting member 49 based on the origin position in the Y-axis direction (see FIG. 6).

After the end of step 5, the CPU (deflection amount calculation unit 61) of the NC control device 51 determines the pair of movable columns 27 in the L-axis direction based on the pressing force of the workpiece W against the abutting surfaces 49 a of the pair of abutting members 49. The amount of collapse is calculated (step 6 in FIG. 5). Specifically, by the CPU (falling amount calculation unit 63) of the NC control unit 51,
λ ₁ = f (P ₁ , Z ₁ ) (4) λ ₂ = f (P ₂ , Z ₂ ) ... By applying equation (5), the amount of tilt of the pair of movable struts 27 in the L-axis direction is calculated. Calculate.

Where λ _{1 is the} amount of tilt of one movable support 27 in the L-axis direction, λ _{2 is the} amount of tilt of the other movable support 27 in the L-axis direction, and Z _{1 is} the length of one movable support 27 in the Z-axis direction. (Height), Z ₂ : The length of the other movable support column 27 in the Z-axis direction, and (4) and (5) depend on the bending rigidity characteristic of the Z-axis.

After step 6 is completed, the target L value is corrected based on the amount of bending of the stretch 37 in the L-axis direction and the amount of collapse of the pair of movable struts 27 in the L-axis direction by the CPU (deflection amount calculation unit 61) of the NC controller 51. (Step 7 in FIG. 5). Specifically, by the CPU (deflection amount calculation unit 61) of the NC control device 51,
α ₁ = δ + λ ₁ Equation (6) α ₂ = δ + λ ₂ Equation (7) is applied,
The target L value is corrected.

Here, α _{1 is} the correction amount of the target L value of one abutting member 49, and α _{2 is} the correction amount of the target L value of the other abutting member 49.

  After the end of step 7, the pair of L-axis servomotors 21 is controlled based on the corrected target L value by the CPU (L-axis motor control unit 53) of the NC control device 51 (step 8 in FIG. 5).

  After the end of step 8, the CPU of the NC control device 51 determines whether the punch die 3 has contacted the workpiece W (in other words, whether the punch die 3 has reached the pinching point). (Step 9 in FIG. 5). If it is determined that the punch die 3 has contacted the workpiece W, the correction of the target L value is completed (step 10 in FIG. 5), while the punch die 3 has not contacted the workpiece W. If so, the process proceeds to step 3 before. As a result, the abutting position of the workpiece W can be corrected according to the pressing force of the workpiece W against the abutting surfaces 49a of the pair of abutting members 49 until immediately before the bending of the workpiece W is started.

After step 9 is finished, the workpiece W is bent by the cooperation of the punch die 3 and the die die 5 by lowering the upper table 13 (step 11).
Therefore, according to the embodiment of the present invention, the abutting position of the workpiece W is corrected according to the pressing force of the workpiece W against the abutting surfaces 49a of the pair of abutting members 49 until just before the bending of the workpiece W is started. Therefore, the workpiece W can be positioned with high accuracy with respect to the mold (die mold 5, punch mold 3) without increasing the rigidity of the stretch 37 or the like. For this reason, the movement speed of the stretch 37 and the like can be increased by reducing the weight of the stretch 37 and the like, and the time required for positioning the work W can be shortened, and the bending accuracy of the work W can be improved.

  The present invention is not limited to the description of the above-described embodiment. For example, the present invention is based on the amount of change in the current value of the pair of L-axis servomotors 21 by the CPU (pressing force calculation unit 59) of the NC control device 51. Instead of calculating the pressing force of the workpiece W, the pressing force of the workpiece W can be directly detected by a load sensor provided on the workpiece abutting member 49, and various other modes can be used. Further, the scope of rights encompassed by the present invention is not limited to these embodiments.

DESCRIPTION OF SYMBOLS 1 Bending machine 3 Punch die 5 Die die 7 Main body frame 11 Lower table 13 Upper table 15 Hydraulic cylinder 17 L-axis supporter 19 L-axis slider 21 L-axis servo motor 27 Movable support column 31 Z-axis servo motor 37 Stretch 39 Y-axis Slider 43 Y-axis servo motor 49 Abutting member 49a Abutting surface 51 NC controller 53 L-axis motor control unit 55 Z-axis motor control unit 57 Y-axis motor control unit 59 Pressing force calculation unit 61 Deflection amount calculation unit 63 Falling amount calculation Part 65 Target L value correction part

Claims (4)

In a bending machine that bends plate-like workpieces by the cooperation of punch dies and die dies,
A lower table provided in a lower part of the main body frame, detachably provided on the upper side and extending in the Y-axis direction;
An upper part of the main body frame is vertically opposed to the lower table, and can be moved up and down relatively with respect to the lower table. An extended upper table,
A pair of L-axis supporters provided in the body frame or the lower table and spaced apart in the Y-axis direction, and extending in the L-axis direction;
Stretched between the pair of L-axis supporters, movable in the L-axis direction, and extended in the Y-axis direction;
An L-axis control motor for moving the stretch in the L-axis direction;
An abutting member provided on the stretch and having an abutting surface capable of butting the end surface of the workpiece;
L-axis motor control means for controlling the L-axis control motor based on a target L value so that the abutting surface of the abutting member is located at a predetermined position in the L-axis direction;
A deflection amount calculating means for calculating a deflection amount of the stretch in the L-axis direction based on a pressing force of the workpiece against the abutting surface of the abutting member;
A bending machine comprising: a target L value correcting unit that corrects a target L value based on a bending amount of the stretch in the L-axis direction. Each L-axis supporter has a movable support column provided so as to be movable in the L-axis direction,
The bending machine according to claim 1, wherein the stretch is constructed between the pair of L-axis supporters via the pair of movable support columns. A tilt amount calculating means for calculating a tilt amount of the movable support column in the L-axis direction based on a pressing force of the workpiece against the abutting surface of the abutting member;
3. The bending process according to claim 2, wherein the target L value correcting unit corrects the target L value based on a deflection amount of the stretch in the L-axis direction and a tilt amount of the movable column in the L-axis direction. Machine.   2. A pressing force calculating means for calculating a pressing force of a workpiece against the abutting surface of the abutting member based on a change amount of a current value of the L-axis control motor. The bending machine according to claim 3.

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