JP2015131305A - Bending device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bending device capable of controlling a bending angle finely even if the positioning resolution power of a punch and a die by a drive mechanism is not enhanced.SOLUTION: The right and left side plates 2 of a press brake are constituted of three unit side plates 21, 22 and 23, and the number of unit side plates for receiving a working reaction force is adjusted by the withdrawal of a connection pin 26 so that the substantial effective thicknesses TA, TB and TC of the side plate 2 are adjusted to adjust the rigidity of the side plates. By the adjustment of the warpage of the right and left side plates 2 generated at the time of receiving the working reaction, moreover, a punch and a die can be positioned more finely than the positioning resolution by a drive mechanism.

Description

  The present invention relates to a bending apparatus such as a press brake for bending a plate-shaped workpiece, for example.

  In a press brake, which is one of bending apparatuses, a plate-like workpiece is bent while a punch and a die are pressed and positioned by a drive mechanism such as a hydraulic cylinder (see, for example, Patent Document 1).

  Here, for example, when the punch and die positioning resolution by the drive mechanism is 0.01 mm, the bending is performed while the punch is pushed stepwise by 0.01 mm into the work on the die.

  Now, when a certain plate-shaped workpiece is bent, the bending angle of the workpiece is changed by about 20 'by pushing a punch into the workpiece on the die by 0.01 mm. In other words, it is assumed that the bending angle of the flat workpiece is changed from 180 ° to 179 ° 40 ′ by pushing the punch into the workpiece on the die by 0.01 mm. However, in this case, since the punch and die positioning resolution is 0.01 mm, the bending angle can be changed only every 20 '.

  For example, when bending is performed aiming at a target angle of 90 °, it is assumed that the actually measured bending angle is 90 ° 10 ′. In that case, it is desired to correct -10 ', but since the minimum setting unit for punch and die positioning is 0.01 mm, if it is corrected, it will be 89 ° 50'. That is, 10 'cannot be corrected.

  Therefore, in order to correct a bending angle smaller than 20 ', it is necessary to set the punch positioning accuracy with respect to the die higher. For example, it is necessary to perform bending by changing the resolution of 0.01 mm to 0.005 mm.

JP 2003-88918 A

  As described above, in order to increase the bending accuracy of the workpiece, it is necessary to increase the positioning resolution of the drive mechanism for pressurizing positioning of the punch and the die.

  In consideration of the above circumstances, the present invention provides a bending apparatus capable of finely controlling the bending angle and increasing the bending accuracy of the workpiece without increasing the resolution of punch and die positioning by the drive mechanism. The purpose is to provide.

  In order to solve the above-mentioned problems, the bending apparatus according to the first aspect of the present invention includes a left and right side plate, an upper table that holds a punch at a lower end and is supported by the upper portion of the left and right side plates, and an upper end that faces the punch A lower table supported by the lower portions of the left and right side plates, and a plate-like workpiece is bent between the punch and the die by relatively moving the upper table and the lower table closer to each other. A bending mechanism for supporting the processing reaction force generated during the bending process by the left and right side plates via the upper table and the lower table when receiving the processing reaction force. The present invention is characterized in that a bending adjusting means for adjusting the degree of bending of the left and right side plates is provided.

  A bending apparatus according to a second aspect of the present invention is the bending apparatus according to the first aspect, wherein the rigidity adjusting means that adjusts the degree of bending of the side plate by adjusting the rigidity of the left and right side plates, It is provided as a deflection adjusting means.

  A bending apparatus according to a third aspect of the present invention is the bending apparatus according to the second aspect, wherein, as the deflection adjusting means, the effective thickness of the side plate that receives the processing reaction force is adjusted by adjusting the effective thickness of the side plate. It is characterized in that a thickness adjusting means for adjusting the rigidity is provided.

  A bending apparatus according to a fourth aspect of the present invention is the bending apparatus according to the second aspect, wherein as the deflection adjusting means, the rigidity of the side plate is adjusted by adjusting an effective area of the side plate that receives the processing reaction force. It is characterized in that an area adjusting means for adjusting the angle is provided.

  A bending apparatus according to a fifth aspect of the present invention is the bending apparatus according to the first aspect, wherein when the side plate receives a vertical tensile force due to the processing reaction force and generates bending, A compressive force adding means for reducing the tensile force and adjusting the bending of the side plate by applying a compressive force between the upper part and the lower part is provided as the bending adjusting means.

  A bending apparatus according to a sixth aspect of the present invention is the bending apparatus according to the fifth aspect, wherein the compressive force adding means applies a compressive force between the upper portion and the lower portion of the side plate. It is characterized by comprising a connecting member connected while being connected, and a compressive force adjusting means for adjusting the compressive force applied between the upper part and the lower part of the side plate via the connecting member.

  According to the bending apparatus of the first aspect of the present invention, the resolution of positioning of the punch and the die can be changed by adjusting the degree of bending of the side plate when subjected to the processing reaction force. Accordingly, it is possible to finely control the bending angle of the workpiece without increasing the resolution of the punch and die positioning by the drive mechanism, and it is possible to increase the bending accuracy of the workpiece.

  According to the bending apparatus of the second aspect of the invention, by adjusting the rigidity of the side plate, it is possible to finely control the bending angle of the workpiece without increasing the resolution of the punch and die positioning by the drive mechanism. Become.

  According to the bending apparatus of the invention of claim 3, by adjusting the effective thickness of the side plate that receives the processing reaction force, it is possible to control the bending angle of the workpiece without increasing the resolution of punch and die positioning by the drive mechanism. Can be performed in detail.

  According to the bending apparatus of the invention of claim 4, by adjusting the effective area of the side plate that receives the processing reaction force, it is possible to control the bending angle of the workpiece without increasing the resolution of punch and die positioning by the drive mechanism. It becomes possible to carry out finely.

  According to the bending apparatus of the fifth aspect of the invention, the vertical tensile force acting on the side plate when subjected to the processing reaction force can be reduced by the compressive force introduced into the side plate. Therefore, it is possible to adjust the degree of bending of the side plate when subjected to the processing reaction force, thereby finely controlling the bending angle of the workpiece without increasing the resolution of punch and die positioning by the drive mechanism. Is possible.

  According to the bending apparatus of the sixth aspect of the invention, the compression force applied between the upper part and the lower part of the side plate can be adjusted via the connecting member by the compression force adjusting means. It is possible to adjust the degree of bending of the side plate when it receives. Therefore, the bending angle of the workpiece can be finely controlled without increasing the resolution of the punch and die positioning by the drive mechanism.

It is a side view for an outline explanation of a press brake mentioned as a bending device of a 1st embodiment of the present invention. FIG. 4 is a diagram showing a positional relationship between a punch and a die during bending by the press brake, wherein (a) shows a positional relationship between the punch and the die when at a bending start point, and (b) achieves a bending angle θ. It is a figure which shows the positional relationship of a punch and die | dye at the time. It is a front view which shows the principle structure of the press brake mentioned as a bending apparatus of 1st Embodiment. FIG. 4 is a perspective view showing a schematic configuration of left and right side plates in the press brake of FIG. 3. (A)-(c) is an effect | action explanatory drawing of the press brake mentioned as a bending apparatus of 1st Embodiment. It is a flowchart for operation | movement description of the press brake mentioned as a bending apparatus of 1st Embodiment. It is a side view for the principle explanation of the press brake mentioned as a bending apparatus of 2nd Embodiment of this invention. It is the figure seen from the front side of the press brake of the side plate in the press brake shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a side view for explaining the outline of a press brake cited as the bending apparatus of the first embodiment, and FIG. 2 is a view showing the positional relationship between a punch and a die during bending by the press brake. ) Is a diagram showing the positional relationship between the punch and the die at the bending start point, FIG. 2B is a diagram showing the positional relationship between the punch and the die when the bending angle θ is achieved, and FIG. FIG. 4 is a perspective view showing a schematic configuration of left and right side plates in the press brake of FIG. 3, and FIGS. 5A to 5C are explanatory views of the operation of the press brake.

  As shown in FIGS. 1-4, the press brake 1 mentioned as a bending apparatus of 1st Embodiment hold | maintains the punch P at the lower end and the beam member 3 which connects the left and right side plates 2, and the left and right side plates 2. An upper table 4 supported on the upper part of the left and right side plates 2, a lower table 5 holding a die D facing the punch P at the upper end and supported on the lower parts of the left and right side plates 2, an upper table 4 and a lower table 5 A drive mechanism 7 for raising and lowering such as a hydraulic cylinder that bends the plate-like workpiece W between the punch P and the die D by relatively moving to and away from each other is provided.

  The drive mechanism 7 in the illustrated example is provided on the top of the side plate 2 to move the upper table 4 up and down with respect to the fixed lower table 5, but on the contrary, with respect to the fixed upper table 4. The lower table 5 may be provided in the lower part of the side plate 2 to move up and down.

  In this press brake 1, the upper table 4 is moved down by the drive mechanism 7, and the punch P is pressed and positioned with respect to the workpiece W placed on the die D, whereby the plate-like workpiece W is interposed between the punch P and the die D. Is bent. At this time, the processing reaction force generated by the bending process is supported by the left and right side plates 2 via the upper table 4 and the lower table 5.

  Now, it is assumed that the side plate 2 has a very high rigidity, and the side plate 2 can be ignored during processing. That is, it is assumed that the deflection of the side plate 2 when subjected to the pressure reaction force is close to zero. Consider a case where the positioning resolution of the punch P by the drive mechanism 7 is, for example, 0.01 mm.

  Under this condition, when a certain plate-shaped workpiece W is bent, the bending angle of the workpiece W is changed by about 20 'by pushing the punch P into the workpiece W on the die D by 0.01 mm. To do. That is, as shown in FIGS. 2A and 2B, the bending angle θ of the flat workpiece W is 180 ° by pushing the punch P against the workpiece W on the die D by h = 0.01 mm. From 179 ° 40 ′.

  In this case, since the positioning resolution of the punch P and the die D by the drive mechanism 7 is 0.01 mm, the bending angle can be changed only every 20 '. Accordingly, as described above, even when it is desired to correct the bending angle −10 ′, the correction cannot be performed.

  Then, consider the case where the rigidity of the side plate 2 is lowered and the punch P is pushed into the die D by 0.01 mm in the same manner. In this case, it is assumed that bending is not performed (the bending angle θ is not changed) because the side plate 2 bends and escapes when receiving the processing reaction force. Then, in that case, it can be determined that the side plate 2 has deflected and escaped by an amount corresponding to the feed amount of 0.01 mm by which the drive mechanism 7 has pushed the punch P into the die D.

  For example, when the change of the bending angle is zero when the punch P is pushed into the workpiece W by 0.01 mm while applying a load of 2 ton by the driving mechanism 7, the side plate 2 is 0.01 mm by the load of 2 ton. It can be judged that it has bent. That is, the deflection per unit of the side plate 2 can be calculated to be 0.005 mm / ton.

  From the result, it can be seen that if the deflection of the side plate 2 is controlled, the pushing amount of the punch P acting on the workpiece W can be set to a value smaller than 0.01 mm.

For example, it is assumed that the deflection (escape) of the side plate 2 when the punch P is pushed by 0.01 mm by the drive mechanism 7 is 0.005 mm. In that case, the actual pushing amount of the punch P acting on the workpiece W is
(Feeding amount by the drive mechanism 7)-(Escape amount due to bending of the side plate 2)
Can be calculated with
0.01mm-0.005mm = 0.005mm
It becomes.

  Then, it can be estimated that the bending angle of the workpiece W changes by 10 ′ with respect to the actual pushing amount of 0.005 mm, and the bending angle can be changed by an angle smaller than 20 ′.

  From such considerations, the press brake 1 is provided with a bending adjusting means for adjusting the degree of bending of the left and right side plates 2 that is generated when a processing reaction force is applied. In particular, in the present embodiment, the stiffness adjusting means for adjusting the stiffness of the left and right side plates 2 is provided as the deflection adjusting means. Specifically, a thickness adjusting means for adjusting the rigidity of the side plate 2 by adjusting the effective thickness of the side plate 2 that receives the processing reaction force is provided as the rigidity adjusting means.

  The thickness adjusting means (rigidity adjusting means, deflection adjusting means) 30 for adjusting the rigidity of the side plate 2 will be described in detail below with reference to FIGS.

  Here, the left and right side plates 2 are configured by superimposing three unit side plates 21, 22, and 23, respectively. The number of unit side plates may be any number (two or four or more) as long as it is a plurality, but for the sake of clarity, a case of three will be described as an example.

  The unit side plates 21, 22, and 23 may be arranged in close contact with each other, or may be arranged with a gap. In the present embodiment, the unit side plates 21, 22, and 23 are made of the same material, the same thickness, and the same shape. However, the material, thickness, and shape may be different from each other.

  Suppose that the deflection when a load of 1 ton (working reaction force) is applied to one unit side plate 21, 22, 23 is 0.01 mm. Then, in the calculation, the deflection when the load is received by the two unit side plates 21 and 22 is about 0.005 mm which is ½. Further, when the load is received by the three unit side plates 21, 22, and 23, the deflection is about 1/3, which is about 0.003 mm.

  Therefore, the unit side plates 21, 22, and 23 can be integrally coupled to or released from an arbitrary number with the coupling pins 26 that are passed through the communication holes 25 for coupling. That is, a plurality of communication holes 25 are formed in each of the three unit side plates 21, 22, 23, and the connection pins 26 that pass through the first unit side plate 21 are connected to the communication holes 25 through the connection pins 26. The first and third unit side plates 22 and 23 can be arbitrarily inserted and removed. However, the pressure reaction force received by the upper table 4 and the lower table 5 is applied to the first unit side plate 21.

In this way, the substantial thickness of the side plate 2 that receives the processing reaction force is determined by the insertion / removal position of the connecting pin 26.
(1) In the case of thickness TA for three sheets as shown in FIG. 5 (a) (2) In the case of thickness TB for two sheets as shown in FIG. 5 (b) (3) As shown in FIG. 5 (c) Thus, the thickness can be selectively changed in the case of the thickness TC for one sheet.

  Here, when the connecting pins 26 are inserted into the second and third unit side plates 22 and 23, the processing reaction force applied to the first unit side plate 21 is 2 It arrange | positions in the position fully transmitted with respect to the 1st sheet and the 3rd unit side board 22 and 23. In other words, in the case (2) in which the first and second unit side plates 21 and 22 are coupled by the connecting pin 26, the side plate 2 has a thickness TB substantially equivalent to two unit side plates. It behaves mechanically as if it were a sheet of side plates. In the case of (1) in which the first, second, and third unit side plates 21, 22, and 23 are coupled by the connecting pin 26, the side plate 2 substantially corresponds to three unit side plates. It behaves dynamically as if it were a single side plate of thickness TA.

  Thereby, in the case of (1), the processing reaction force is received by the three unit side plates 21, 22, 23, and in the case of (2), the processing reaction force is received by the two unit side plates 21, 22. In the case of (3), the processing reaction force is received by one unit side plate 21.

  Accordingly, when the pressure reaction force is applied, in the case of (1) above, the rigidity of the side plate 2 becomes large and the deflection becomes a small 0.003 mm / ton. In the case of (2), the rigidity of the side plate 2 is medium, and the deflection is 0.005 mm / ton. In the case of (3), the rigidity of the side plate 2 is small, and the deflection is a large 0.01 mm / ton.

  Therefore, in order to change the bending angle of the workpiece W more finely, the substantial thickness of the side plate 2 is increased, and the rigidity of the side plate 2 is increased to control the bending to be low. That is, the thickness of the side plate 2 is changed in the increasing direction. In this way, by adjusting the effective thickness of the side plate 2 that receives the processing reaction force, the rigidity of the side plate 2 can be adjusted, whereby the degree of bending of the side plate 2 when receiving the processing reaction force can be adjusted. Can be adjusted.

  Therefore, the positioning resolution of the punch P and the die D can be changed, and as a result, the positioning resolution of the punch P and the die D by the driving mechanism 7 is not increased (that is, the positioning cost of the driving mechanism 7 is increased). However, it is possible to finely control the bending angle of the workpiece W. That is, it becomes possible to position the die D and the punch P finer than the coarse resolution of the drive mechanism 7, thereby increasing the bending accuracy of the workpiece W.

  Next, the flow of processing will be described based on the flowchart shown in FIG.

  First, in the first step 101, as shown in FIG. 5 (a), an initial state in which the three unit side plates 21, 22, 23 are connected is set. In this state, since the rigidity of the side plate 2 is maximized, the deflection is minimized. Next, in step 102, the sample work is bent in this initial state. Then, in step 103, it is confirmed whether the result of actual measurement of the bending angle is OK (appropriate). If the determination in step 103 is yes, the process proceeds to the next processing in step 120.

  If the determination in step 103 is no, the process proceeds to step 104, where the feed amount of the punch by the drive mechanism 7 is corrected to correct the angle. Next, in step 105, the next sample work is bent in that state. Then, in step 106, it is confirmed whether the result of actually measuring the bending angle is OK (appropriate). If the determination in step 106 is YES, the process proceeds to the next processing in step 120.

  If the determination in step 106 is NO, the process proceeds to step 107 to determine whether or not the rigidity of the side plate 2 should be corrected. In the case of NO, it means that the rigidity of the side plate is not corrected. Therefore, the process proceeds to step 108, and the feed amount of the punch P by the drive mechanism 7 is corrected in order to perform angle correction again. Next, in step 109, the next sample work is bent in that state. Then, in step 110, it is confirmed again whether the result of actually measuring the bending angle is OK (appropriate). If the determination in step 110 is YES, the process proceeds to the next processing in step 120, and if NO, the process returns to step 107.

  If the determination in step 107 is YES, that is, if it is determined that the rigidity of the side plate 2 should be corrected, the process proceeds to step 111 and the connecting pin 26 is removed by one step as shown in FIG. Down one step. Then, bending is performed in step 112, and the process returns to step 106. Thereafter, the processing after step 106 is repeated.

  In this way, by controlling the bending by adjusting the rigidity of the side plate 2, the die D and the punch P can be positioned finer than the coarse resolution of the drive mechanism 7, and the bending accuracy of the workpiece W can be improved. Can be raised.

  The connecting pin 26 may be manually inserted or removed by an air cylinder with a position stop function (a function capable of controlling the position to an appropriate insertion / removal position), a hydraulic cylinder, or an electric motor (servo Etc.).

  Further, the control of the bending of the side plate 2 by inserting / removing the connecting pin 26 may be set to the same for the left and right side plates 2 or may be changed.

  Further, the number and location of the connecting pins 26 are preferably set by optimization through analysis.

  In the first embodiment, a case is described in which means (thickness adjusting means 30) for adjusting the effective thickness of the side plate 2 that receives the processing reaction force is provided as means for adjusting the rigidity (deflection) of the side plate 2. However, an area adjusting means for adjusting the rigidity of the side plate by adjusting the effective area of the side plate that receives the processing reaction force may be provided. In any case, the rigidity of the side plate 2 may be adjusted.

  Next, a second embodiment will be described.

  FIG. 7 is a side view for explaining the principle of a press brake cited as a bending apparatus according to the second embodiment, and FIG. 8 is a view seen from the front side of the press brake of the side plate in the press brake shown in FIG.

  As shown in FIG. 7, at the time of bending, the side plate 52 receives a vertical tensile force S due to a processing reaction force and generates a deflection.

  Therefore, in this embodiment, by applying a compressive force in the vertical direction (arrows F1 and F2 in the figure) to the side plate 52, the tensile force S is reduced (a part of the tensile force S is offset), and the side plate 2 is bent. The compression force adding means 60 for adjusting is provided as a deflection adjusting means.

  Specifically, brackets 54 and 53 are fixed to the upper and lower portions of the side plate 52, and the upper and lower brackets 54 and 53 are connected by a connecting rod (connecting member) 55. At this time, the connecting rod 55 is fixed to one bracket 54 via a spring (compression force adjusting means) 57 so that the deformation amount of the spring 57 can be adjusted.

  That is, the lower end of the spring 57 is received by the bracket 54, and the upper end of the spring 57 is received by the movable member 58 screwed to the upper end of the connecting rod 55. Then, the amount of compression of the spring 57 can be adjusted by moving the movable member 58 along the connecting rod 58 so that the compression reaction force of the spring 57 generated at this time acts downward on the bracket 54. is there.

  In this way, if the compression amount of the spring 57 is adjusted, the vertical compression force introduced into the side plate 52 via the connecting rod 55 is adjusted. For example, if the compression amount of the spring 57 is small, a small compression force F2 is introduced into the side plate 52, and if the compression amount of the spring 57 is large, a large compression force F2 is introduced into the side plate 52.

  Therefore, the vertical tensile force acting on the side plate 52 when subjected to the processing reaction force can be reduced by the compressive force introduced between the upper and lower portions of the side plate 52, thereby receiving the processing reaction force. It is possible to adjust the degree of bending of the side plate 52 at the time of hitting. Therefore, it is possible to finely control the bending angle of the workpiece without increasing the resolution of punch and die positioning by the drive mechanism.

  The position adjustment of the movable member 58 for adjusting the compression amount of the spring 57 can be performed manually or by a motor or the like.

DESCRIPTION OF SYMBOLS 1 Press brake 2,52 Side plate 4 Upper table 5 Lower table 7 Drive mechanism P Punch D Die W Workpiece 30 Thickness adjustment means (rigidity adjustment means, deflection adjustment means)
55 Connecting rod (connecting member)
57 Spring (Compression force adjusting means)
60 Compression force adding means (deflection adjusting means)

Claims (6)

Left and right side plates,
An upper table that holds a punch at the lower end and is supported by upper portions of the left and right side plates;
A lower table that holds a die facing the punch at the upper end and is supported by lower portions of the left and right side plates;
A drive mechanism for bending a plate-like workpiece between the punch and the die by relatively moving the upper table and the lower table,
In the bending apparatus for supporting the processing reaction force generated during the bending process by the left and right side plates via the upper table and the lower table,
A bending apparatus comprising a bending adjusting means for adjusting a degree of bending of the left and right side plates generated when the processing reaction force is received. The bending apparatus according to claim 1,
A bending apparatus characterized in that a rigidity adjusting means for adjusting the degree of bending of the side plate by adjusting the rigidity of the left and right side plates is provided as the bending adjusting means. The bending apparatus according to claim 2,
A bending apparatus comprising: a thickness adjusting means for adjusting the rigidity of the side plate by adjusting an effective thickness of the side plate that receives the processing reaction force as the deflection adjusting means. The bending apparatus according to claim 2,
A bending apparatus characterized by comprising an area adjusting means for adjusting the rigidity of the side plate by adjusting an effective area of the side plate that receives the processing reaction force as the deflection adjusting means. The bending apparatus according to claim 1,
When the side plate receives a tensile force in the vertical direction due to the processing reaction force and generates bending, the tensile force is reduced by applying a compressive force between the upper and lower portions of the side plate, and the side plate is bent. A bending apparatus characterized in that a compression force applying means for adjusting the pressure is provided as the deflection adjusting means. The bending apparatus according to claim 5,
The compressive force adding means is
A connecting member that connects the upper and lower portions of the side plate while applying a compressive force between the upper and lower portions, and adjusts the compressive force that is applied between the upper and lower portions of the side plate via the connecting member. A bending apparatus comprising: a compressive force adjusting means that performs

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