JPS62248514A - Correction device for bend angle - Google Patents

Abstract

PURPOSE:To obtain a constant and correct bending angle at all times even with a dimensional difference in the plate thickness by detecting the plate thickness of a plate stock, comparing it with the reference plate thickness and performing the correction of the gap dimension existed between the upper and lower dies according to the dimensional difference thereof. CONSTITUTION:When a plate stock W is first inserted between the supportor 73 and probe 77 of a plate thickness detection device 25, the up and down movement quantity of the probe 77 is inputted to an up and down counter 93 as the data proportional to the pinching thickness of the linear encoder 91 of a measuring instrument 83. The counting thereof is inputted to a peak holding circuit 95 to obtain the minimum value of he pinching plate thickness detection value. The reference plate thickness tr of the plate thickness setting part of the plate stock W and the output (t) of the plate thickness value of the circuit 95 are compared by the bending angle correction device 99 to which the output of the circuit 95 is given and the dimensional difference + or -8 is calculated at a dimensional difference arithmetic part 103. The quantity corresponding to the gap between the upper and lower dies 3, 11 is calculated by a gap correction arithmetic part 105 and the gap dimension of the upper die 11 against the lower die 3 is corrected by a gap correction part 107.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a bending angle correction device in a plate bending machine.

(Prior art) Generally, in a plate bending machine, the gap size when the upper die and the lower die are engaged is determined from the relationship between the plate thickness of the plate used and the target value of the bending angle. There is. Therefore, the gap size is adjusted so that the gap is made large for a plate material with a large thickness, and conversely, the gap is made small for a plate material with a small thickness.

However, even if the plate materials used have the same standard dimensions, since manufacturing tolerances are generally accepted, strictly speaking, all the plate materials do not have the same dimensions, and there are dimensional differences. Therefore, if the gap in the upper mold of the bending machine is set to a constant size, it is difficult to achieve accurate bending angles for all the plates due to the dimensional difference in the thickness of the plates used. I can't.

However, conventional bending machines detect the difference in the thickness of the plate material due to such tolerances, correct the gap size between the upper and lower molds, and make it the same for any plate material. There is no known technique for realizing the bending angle.

(Problems to be Solved by the Invention) As mentioned above, with conventional bending machines, even if plates with the same specifications are used, the bending angle is exactly the same due to the dimensional difference in plate thickness due to tolerances. There was a problem that it could not be realized.

This invention solves such conventional problems by detecting the thickness of the plate material and correcting the gap size between the upper and lower molds according to the dimensional difference between the plate thickness and the reference plate thickness. However, it is an object of the present invention to provide a bending angle correcting device for a bending machine that makes the bending angle accurately constant.

[Structure of the Invention] (Means for Solving Problems) The bending angle correction device of the present invention includes a means for detecting the thickness of a plate material, and an actual plate thickness determined by the plate thickness detection means as a reference plate thickness. The apparatus is equipped with a comparison means for comparing and determining the difference in plate thickness dimension, a gap correction calculation means for calculating a correction value for the gap between the upper and lower molds according to this dimensional difference, and a means for performing gap correction. .

(Function) The bending angle correction device of the present invention detects the dimensional difference between the actual thickness of the plate material used and the reference plate thickness, and
The gap size between the upper and lower molds is corrected according to the normal difference, so that even if there is a dimensional difference in plate thickness, the same bending angle can always be obtained.

(Embodiment) FIGS. 6 and 7 show the entire plate material bending machine 1 using an embodiment of the present invention.

This sheet material bending machine 1 is generally equipped with a box-shaped machine base 5 that supports a lower die 3, and guide members 7R and 7m provided on the left and right sides of this machine base 5 are provided with guide members 7R and 7m, respectively. The bosses 9R and 9L are supported so as to be vertically movable. The left and right sides of the upper table (ram) 13, which supports the upper die 11 that bends the plate material W in conjunction with the lower die 3, are supported on the upper portions of the left and right guide posts 9R and 9L. . The lower portions of each of the guide posts 9R, 9L are connected via connecting rods 17R, 17L to an eccentric portion 15E of an eccentric shaft (crankshaft) 15 rotatably supported on the machine base 5.

With the above configuration, by rotating the eccentric shaft 15, the upper table 13 is moved up and down via the guide posts 9R and 9L. Therefore, after positioning the plate material W on the lower mold 3, the eccentric shaft 15 is rotated to lower the upper table 13, and the upper mold 11 is engaged with the lower mold 3.
The plate material W can be bent.

When bending the plate material W as described above, the plate I
In order to detect the positioning state of 4W, the upper table 1
A machining position detection device 19 for optically detecting the machining position of a score line or the like drawn on the plate material W is attached to the rear surface of the plate material W. In addition, in order to accurately position the plate material W based on the detection result of the processing position detection device 19, the lower die 3
A back gauge device 21 is provided at the rear (right side in FIG. 7). Further bending process 1I1
1 is equipped with an appropriate control device 23 such as a numerical control device in order to control each operating section, and also detects the thickness of the plate material W to be processed and uses the data to control the υ control. A plate thickness detection device 25 is provided for outputting to the device.

For more details, see 131J it! The machine base 5 is the left and right side plates 5
R15L and a horizontal upper plate 5U whose left and right sides are supported on the front upper part of the side plates 5R and 5L, and has a roughly box-like structure, and reinforcing plates 5'' are provided at the front and rear of the lower surface of the upper plate 5U, respectively. The installation number is pu.

The eccentric shaft 15 is located below the upper plate 5U of the machine base 5, and its left and right ends are rotatably supported by the side plates 5R and 5L via bearings @27. A driven gear 29 is integrally attached to one end of the eccentric shaft 15, and a driving gear 31 meshes with this driven gear 29. The drive gear 31 is attached to an output shaft 33 of a servo motor (f in the figure) attached to the inside of the side plate 5R. Therefore said control device! By appropriately rotating and stopping the servo motor under the control of t23, the descending speed and stop position of the table 13, and therefore the lower die 3
This allows the gap between the upper mold 11 and the upper mold 11 to be appropriately controlled.

The guide members 7R, 7L that guide the guide posts 9R, 9m up and down are formed in a cylindrical shape, and have an eccentric shaft 15.
The axes are arranged so that their axes are substantially aligned with the vertical plane passing through the axes of the. Each guide member 7R.

7L and each guide post 9R, 9L are fitted together without play, and a ring is provided on the upper part of each guide member 7R, 7m to abut against the upper table 13 supported on each guide post 9R, 9L. Members 35R and 35m are provided to be movable up and down.

Each ring member 35R, 35L is provided so as to come into contact with the upper table 13 before the upper mold 11 engages with the lower mold 3 due to the lowering of the upper table 13, and each ring member 35R, 35L is provided with a guide. It is always urged upward by elastic members 37R and 37L elastically mounted between members 7R and 7L.

Note that the elastic members 37R and 37L are attached to the upper table 13.
It has sufficient strength to push up the total weight of the guide posts 9R, 91, etc.

With the above configuration, when the upper table 13 is lowered to bend the plate material W, the upper table 13 first comes into contact with the ring members 35R, 35L, and is relatively bent by the action of the elastic members 37R, 37m. When the upper table 13 is positioned in the vicinity of the bottom dead center, the upper table 13 can be positioned with good flexibility, with the play of each connecting portion being moved in one direction.

In order to adjust the height position of the upper table 13 in response to changes in the height of the upper and lower molds 11, 3 and changes in the thickness of the plate material W, the left and right sides of the upper table 13 are provided with the guide posts 9R. , 9L so that the lower position can be adjusted freely.

More specifically, at the upper end of each guide post 9R, 9m, a cylindrical rotating body 39 is provided with a threaded portion 398 on the lower side.
R and 39L are rotatably supported. Cheno sprockets 41R, 41L are integrally attached to each rotating body 39R, 39L so as to rotate in synchronization with each other, and an endless chino sprocket 43 is wound around each of these chino sprockets 41R, 41L. ing.

A driven gear 39G is appropriately provided integrally with one of the rotating bodies 39R, and a drive gear 45 meshes with this driven gear 39G. The drive gear 45 is connected to an adjustment motor 4 supported on the upper table 13 via a bracket 47.
It is attached to the output shaft of 9. On the other hand, each rotating body 39R
, 39L are screwed into nut members 51R, 51L attached to both sides of the upper table 13.

Therefore, when the adjustment motor 49 is rotationally driven under the control of the control device W123, each chenno sprocket 4
1R and 41L rotate synchronously via a chino 43. Therefore, each rotating body 39R, 39m rotates synchronously, and each rotating body 3
Nut member 51 screwed into threaded portions 39S of 9R and 39L
The upper table 13 is positioned vertically via R and 51L.
It will be stipulated.

The plate thickness detecting device 25 that detects the plate thickness of the plate material W has a sixth plate thickness detecting device 25.
As shown in the figure, it is attached via a mounting block 53 attached to the side surface of the upper member 5U of the machine base 5.

As shown in detail in FIGS. 8 and 9, a branch 57 is supported on the mounting block 53 via a pivot 55 so that it can be raised and lowered, and an arcuate portion formed at the base of the support 57 A plurality of recesses 59A and 59B are formed in the. On the other hand, the mounting block 53 has a plunger 6 rotatably provided with a roller 61 that can be freely engaged with and disengaged from the recesses 59A and 59B.
3 is slidably installed inside. This plunger 63
The plunger 63
is always pressed toward the base of the support column 57. Also,
A stopper 69 is provided on the mounting block 53.

A base block 71 having an inverted cross section is attached to the tip of the support column 57. A semicircular support 73 for supporting the plate material W is integrally attached to the protruding portion of the base block 71, and an abutting block 75 for abutting the plate material W is also attached. Furthermore, a holder block 79 that supports a hemispherical contact 77 facing the support 73 so as to be movable in the axial direction is integrally attached to the base block 71 so as to face and be spaced apart from the protrusion of the base block 71. It is. The holder block 79 is equipped with a measuring device 83 such as a linear encoder, a dicill gauge, or a differential transformer that detects the amount of movement of the spindle 81 by contacting the contact 77.

A plate material W is inserted between the supporter 73 and the contactor 77 in the holder block 79, and the abutment block 75
A limit switch 85 is installed to detect contact with the actuator 8 of the limit switch 85.
A protection plate 89 that protects 7 is swingably supported.

With the above configuration, as shown in FIG. 8, by appropriately rotating the support 57 and selectively engaging the rollers 61 in the recesses 59A and 59B, the support 57 can be placed in the usable vertical state or Can be kept in a horizontal position when not in use. Holding the support column 57 in a vertical state, the supporter 73 and the contactor 77
When the plate material W is inserted between and abuts against the abutment block 75, the limit switch 85 is activated and becomes ready for measurement.

As mentioned above, the plate material W is provided between the supporter 73 and the contactor 77.
The measuring device 83 detects the thickness of the plate material W by inserting the plate material W. At this time, the upper part of the supporter 73 is used as a fulcrum and the plate +
4 When W is swung up and down, the contactor 77 moves up and down, and the measured value of the measuring device 83 changes. Therefore, the minimum value of the measured values is stored in the control R@23, and the minimum value is determined as the thickness of the plate material W. Based on the plate thickness, the position of the upper table 13 can be controlled according to the bending angle, etc., and each necessary operating section can be controlled.

Referring to Figures 2 to 4, this plate thickness detection device! ! 25
The electrical configuration and operation of the will be explained in detail.

The plate material W is inserted between the supporter 73 and the contactor 77, which constitute means for holding the plate material W. The amount of vertical movement of the contactor 77 is detected by a linear encoder 91 that constitutes the measuring device 83. The output of the linear encoder 91 that is proportional to the thickness of the clamp is input to an up/down counter 93. The count of the up/down counter 93 is input to a peak hold circuit 95 which serves as means for detecting a small value of the amount of buoyancy, and the minimum value of the detected value of the buoyancy thickness is determined here. The obtained minimum value of the sandwich thickness is displayed by the plate thickness display section 97 as the regular plate thickness t.

Further, the output of this peak hold circuit 95 is given to a bending angle correction device 99, and the bending process I! It is used to correct the gap dimension between the upper and lower molds 3 and 11.

This bending angle correction device 99 uses a setting section 101 for setting a reference plate thickness tr of the plate material W to be used, and an output t of the plate thickness value of the peak hold circuit 95 from the reference plate F from this plate thickness setting section 101.
Dimensional difference calculation unit 1 that compares with Jtr and calculates the dimensional difference ±δ
03. The bending angle correction device 499 further includes a gap correction calculating section 105, and a gap correcting section 10 that adjusts the gap between the upper and lower molds 3, 11 by an amount commensurate with the gap correction value by the gap correction calculating section 105.
It has 7. The gap correction section 107 controls the adjustment motor 49 to change the height of the upper table 13 and corrects the gap dimension between the upper mold 11 and the lower mold 3.

Plate thickness detection device 25 and bending angle correction device 99 configured as described above
is included in the control device 23 and is operated by a microcomputer, and its operation will be explained below.

Referring to the flowchart shown in FIG. 3, first, it is determined whether the plate material W is inserted into the plate thickness detection device 25 by the operation of the limit switch 85 - step 11
1° When the plate material W is inserted, the plate thickness detection operation is started, and the first measurement of the pinching thickness t1 is performed - Steps 113 to 117° The pinching thickness measurement for this plate material W is performed with respect to the supporter 73. This is done by detecting the amount of movement of the contact 77 with a linear encoder 91 and counting it with an up/down counter 93. And this first pinching thickness t
1 is stored in the peak hold circuit 95 as the plate thickness t until the next measurement value is obtained.

Subsequently, the operation of measuring the pinching thickness tl from the second time onward is repeated at regular time intervals - steps 119 to 129.
゜The second and subsequent clamping thickness measurements are performed while the operator holds the plate W and slowly swings it up and down with the plate material W clamped between the supporter 73 and the contactor 77 - step 119;
121° and linear encoder 91, counter 93
The count value of the clamping thickness t1 is taken into the peak hold circuit 95 at regular intervals and compared with the minimum value t of the clamping thickness up to the previous time, and if this latest value tl is smaller than the minimum value t up to the previous time, This latest value tl is set as the new minimum value t, and the value is displayed. On the other hand, if the minimum g1t from the previous time is smaller, that minimum fat is retained this time as well, and the process moves on to the next sandwich thickness measurement ti+1 - steps 123 to 127 degrees. The measurement continues periodically until the plate material W is removed and the limit switch 85 is turned off - step 129. Thus, the minimum value t of the obtained clamping thickness tl is determined to be the normal thickness of the plate material W. t is determined and displayed.

The plate thickness t obtained by this plate thickness detection device 2225 is determined by the bending angle correction RIF? given to 99. The operation of this bending angle correction device 99 will be explained based on the flowchart of FIG.

The measured value t from the plate thickness detection device 25 is determined by the dimensional difference calculation unit 10.
3, and here the plate thickness setting is 11i! Steps 131 and 133 degrees in which the dimensional difference ±δ with respect to the set value tr is calculated by comparing it with tr are followed by correction of the gap G between the upper and lower molds 3° 11 using this dimensional difference ±δ. This gap G correction is based on the following reason. In other words, as shown in FIG.
The gap G between the upper die 11 and the upper die 11 is experimentally determined from the relationship between the reference plate thickness tr of the plate material W to be used and the intended bending angle θ1. However, in general, the actual thickness t of the plate material W is allowed to have manufacturing tolerances, so there is a dimensional difference with respect to the standard plate thickness t. If so, during the actual bending process, when the gap G is constant, the bending angle changes to θ2, and the desired bending angle θ1 cannot be obtained.

Therefore, by adjusting the gap G to be wider or narrower depending on the actual plate thickness t, a constant bending angle θ1 can be obtained without being affected by the dimensional difference in plate thickness.

Therefore, returning to the flowchart of FIG. 4, the correction amount of the gap G is calculated according to the dimensional deviation ±δ, and the position of the upper die 11 is adjusted based on the correction value - steps 135 to 139°. This correction calculation formula for the gap G should be determined experimentally, and can be registered in advance as a table in the gap correction calculation unit 105.

In this way, the plate thickness detection device! Actual plate J of plate material W detected by 25! Based on lIt, upper and lower molds 3,
This bending angle correction device 99 corrects the gap G of 11.
Even if there is a difference in plate thickness, the plate material W can always be bent at a constant bending angle θ1.

[Effects of the Invention] Since the present invention has the above configuration, even if there is a dimensional difference in the thickness of the plate material used from the standard plate thickness, the gap size between the upper and lower molds can be adjusted according to the dimensional difference. It has the advantage of being able to perform corrections and always achieve a constant and accurate bending angle.

[Brief explanation of drawings]

Fig. 1 is a diagram corresponding to the claims of the present invention, Fig. 2 is a circuit block diagram of an embodiment of the invention, and Fig. 3 is a flowchart showing the operation of the plate thickness detection device portion in the above embodiment.
Fig. 4 is a flowchart showing the gap correction operation of the above embodiment, Fig. 5 is an explanatory diagram showing changes in the bending angle due to the difference in plate thickness in the bending machine, and Fig. 6 is a flowchart showing the gap correction operation of the above embodiment. FIG. 7 is a front view of the bending machine, FIG. 7 is a side view of the bending machine, FIG. 8 is a side view showing the mechanical configuration of the plate thickness detection device used in the above embodiment, and FIG. 9 is a side view of the bending machine. FIG. 3 is a side view showing how a limit switch used in the thickness detection device is installed. 1...Bending machine 3...Lower die 11...Upper die 25...Plate thickness detection device 73...Supporter 77...Contactor 91...Linear encoder 93... Counter 95...Peak hold circuit 99...Bending angle correction device 101...Plate thickness setting section 103...Dimension difference calculation section 105...Gap correction calculation section 107...Gap correction section agent Patent Attorney Yasuo Miyoshi 1tl:,'-
';-+ :'-+ Figure 1 Figure 3 Figure 4 Figure 5M

Claims (1)

[Claims] A means for detecting the actual thickness of a plate; a comparison means for comparing the actual thickness detected by the thickness detection means with a reference thickness to calculate a dimensional difference in plate thickness; and an output of the dimensional difference by the comparison means. a means for calculating a correction value for the gap dimension between the upper mold and the lower mold of the bending machine according to the above, and a means for calculating the actual gap dimension between the upper mold and the lower mold according to the calculated value of the gap correction calculation means. A bending angle correction device comprising gap correction means for correcting.