JP2005238409A - Suction adjusting method and device of cutter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cut even an elastic sheet material in a proper compression state, by restraining a height change in a surface of the sheet material sucked on a table. <P>SOLUTION: When cutting the sheet material 5 by a cutter 1 for moving a cutting blade 13 to the cutting table 4 in response to preset data while sucking and holding the sheet material on the table 4, the height change in the surface of the sheet material 5 pressed down by a presser 14 is grasped. Leakage increases in response to an advance of cutting, and a state of increasing in the height of the surface of the sheet material by reduction in suction force can be grasped. Since a suction state is adjusted so as to compensate for reduction in holding power to the sheet material 5 by an increase in the leakage caused by the advance of the cutting, even the elastic sheet material 5 can be cut in the proper compression state by restraining the height change in the surface of the sheet material 5 sucked on the cutting table 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a suction adjustment method and apparatus for a cutting machine that holds and cuts a flexible sheet material such as a cloth while sucking it on a table.

  2. Description of the Related Art Conventionally, a cutting machine has been used in which a sheet material to be cut is placed on a support surface of a breathable table and cut according to data created in advance. The cutting machine moves the cutting head along the table while holding the sheet material so as not to easily move on the table, and cuts the sheet material with a cutting blade provided in the cutting head. The table of the cutting machine is also called a cutting table, a cutting bed, or the like, and a brush-like member called a bristle brush is arranged to form a support surface at the tip of the brush. The bristle brush is formed of an elastic synthetic resin or the like, and at the portion where the cutting blade is pierced, the bristle of the brush is pushed by the cutting blade and bends and escapes from the cutting blade, so it is not cut. As the cutting blade moves to another location, the bristles of the brush return to the original position to support the sheet material.

  Since the sheet material has air permeability, when a plurality of sheets are laminated and simultaneously cut, the whole is sucked by covering with a non-air-permeable covering sheet. The cutting blade cuts the covering sheet together with the sheet material. If there is an abnormality such as wrinkles on the sheet material or double folding, even if the sheet material is cut while moving the cutting head according to the data, the outline of the part is cut accurately. I can't do that. When the applicant detects an abnormality in the height of the surface that hinders accurate cutting of the material to be cut, such as sheet material, the cutting machine stops the cutting and displays a warning. An apparatus for detecting an abnormality of a material to be cut in a machine is disclosed (for example, see Patent Document 1).

  Since the suction force on the table acts on the covering sheet covering the surface of the laminated sheet material, the sheet material is compressed on the surface of the table. If the suction force on the table is not uniform, the compression state of the sheet material changes, the height of the surface of the sheet material from the table surface also changes, and the surface of the sheet material has a portion inclined with respect to the table surface. Since the cutting blade cuts on the premise that the surface of the sheet material is parallel to the surface of the table, accurate cutting cannot be performed at a portion where the surface is inclined. In addition, among the plurality of laminated sheet materials, the sheet material close to the table is kept parallel to the surface of the table, so the degree of inclination of the sheet material changes depending on the lamination position, It becomes impossible to cut the sheet material in the same shape.

  Since the shape of the table holding the sheet material is relatively large, it is difficult to make the suction force of the table uniform. In addition, there is a time delay until the control result in the portion that generates the suction force is reflected in the retention of the sheet material on the support surface. For this reason, it is possible to adjust the suction force by dividing the support surface of the table into multiple areas, predict the movement of the cutting blade, and control the suction force prior to actually starting cutting It has been proposed (see, for example, Patent Document 2). In Patent Document 2, when there is a time delay in the control of the suction force, pressurization and pressure reduction are alternately repeated in the same region that is divided and sucked to prevent a phenomenon called thrashing from occurring. The purpose is that.

Japanese Patent No. 3149117 Japanese Patent Laid-Open No. 7-205091

  The sheet material to be cut by the cutting machine includes not only cloth for clothing but also cushion materials such as furniture and automobile seat material, and expanded foam. In some cases, pile fabric is cut. These are elastic, and when they are covered with a cover sheet and sucked on a table of a cutting machine, the thickness is reduced by compression according to the suction force. As the cutting progresses, the covering sheet is also cut along the already cut lines of the cut parts, and air flows in. The increase in leakage accompanying the progress of cutting causes a reduction in the suction force for holding the sheet material on the table. When the suction force is reduced, the sheet material is moved by the cutting blade at the time of cutting, and not only the cutting accuracy is lowered, but also the degree of compression is weakened and the thickness of the sheet material on the table is increased.

  A method is conceivable in which the suction force is set large so that sufficient sheet material can be retained even when leakage increases. However, with this method, the suction force more than necessary reaches the sheet material at the initial stage of cutting, and the sheet material is excessively compressed. Since the elastic sheet material is not uniformly compressed and is cut in a distorted state, there is a difference in the shape of the cut parts between the upper layer sheet material and the lower layer sheet material that are laminated. . Therefore, in the case of a sheet material having elasticity, it is desired to cut the sheet material so as not to be greatly distorted. Moreover, it is also a wasteful use of energy to always generate an excessive suction force.

  An object of the present invention is to provide a suction adjustment method and apparatus for a cutting machine that suppresses fluctuations in the height of the surface of a sheet material sucked on a table and can cut even an elastic sheet material in an appropriate compressed state. It is to be.

The present invention is a suction adjustment method when cutting with a cutting machine that moves the cutting blade relative to the table according to preset data while sucking and holding the sheet material on the table,
By grasping the change in the height of the surface of the sheet material on the table, the suction state is adjusted so as to compensate for the decrease in the holding force to the sheet material due to the increase in leakage as the cutting progresses This is a suction adjustment method of the cutting machine.

  In the present invention, the adjustment of the suction state is performed every time a part whose contour to be cut is defined by the data is cut.

  In the present invention, the suction state is adjusted according to the height of the surface while cutting the sheet material.

  Further, in the present invention, the adjustment of the suction state is based on grasping the change in the height of the surface, predicting an increase in leakage with the progress of cutting according to the data, and compensating for the increase by increasing the suction force. It is characterized by being performed.

In the present invention, the cutting is performed while pressing the surface of the sheet material with a presser around the cutting blade,
The change in the height of the surface is detected and grasped as a change in the height of the presser.

Further, the present invention is a cutting machine that sucks and holds a sheet material on a table, and adjusts the suction state when cutting the sheet material by moving a cutting head including a cutting blade according to preset data. A suction adjustment device for a cutting machine for
A height detecting means for detecting the height of the surface of the sheet material on the table;
A suction adjustment device for a cutting machine, comprising: suction adjustment means for adjusting a suction state so that the height detected by the height detection means falls within a predetermined range with respect to the progress of cutting. is there.

Further, in the present invention, the cutting machine includes a presser that presses a surface of a sheet material around the cutting blade on the cutting head,
The height detection means detects a change in the height of the surface of the sheet material by detecting the height of the presser.

  According to the present invention, when cutting with a cutting machine that moves the cutting blade with respect to the table according to preset data while sucking and holding the sheet material on the table, the sheet material on the table is Since the change in the height of the surface is grasped, it is possible to grasp a state in which leakage increases as the cutting progresses and the height of the surface of the sheet material increases due to a decrease in the suction force. The suction state is adjusted so as to compensate for the decrease in the holding force to the sheet material due to an increase in leakage as the cutting progresses, so the fluctuation of the surface height of the sheet material sucked on the table is suppressed and elasticity Even a sheet material having a can be cut in an appropriate compressed state.

  Further, according to the present invention, the suction state is adjusted every time a part whose contour to be cut is defined by data is cut, so that each part can be cut accurately.

  Further, according to the present invention, the suction state is adjusted according to the height of the surface while cutting the sheet material. Therefore, accurate cutting is performed while suppressing the change in the height of the sheet material being cut. be able to.

  Further, according to the present invention, the adjustment of the suction state is based on grasping the change in the height of the surface, predicting an increase in leakage with the progress of cutting according to the data, and compensating for the increase in leakage with the increase in suction force. Therefore, even if there is a time delay in adjusting the suction force, the height of the surface of the sheet material can be adjusted in accordance with the cutting.

  Further, according to the present invention, when cutting while pressing the surface of the sheet material around the cutting blade with the presser, the change in the height of the surface is detected and grasped as the change in the height of the presser. It is possible to reliably detect and grasp the height of the surface of the sheet material in the state of cutting.

  Further, according to the present invention, when the sheet material is cut by moving the cutting head provided with the cutting blade according to the preset data, the suction state is changed by the cutting machine that sucks the sheet material and holds it on the table. The suction adjustment device of the cutting machine for adjustment includes a height detection means and a suction adjustment means. Since the height detection means detects the height of the surface of the sheet material on the table, leakage increases as the sheet is cut, and even if the height of the surface of the sheet material increases, it is detected and the change is grasped. be able to. The suction adjustment means adjusts the suction state so that the height detected by the height detection means falls within a predetermined range with respect to the progress of cutting, so the surface of the sheet material sucked on the table is adjusted. Even a sheet material having elasticity and suppressing elasticity can be cut in an appropriate compressed state.

  According to the invention, the cutting head of the cutting machine is provided with a presser for pressing the surface of the sheet material around the cutting blade. Since the height detection means detects the change in the height of the surface of the sheet material by detecting the height of the presser, it can reliably detect the height of the surface of the sheet material in the actual cutting state. I can grasp it.

  FIG. 1 shows a schematic external configuration of a cutting machine 1 that executes a suction adjustment method according to an embodiment of the present invention. The cutting machine 1 includes a suction box 3 in a base frame 2 installed on a flat floor or the like. A cutting table 4 is provided on the upper part of the base frame 2, and a plurality of sheet materials 5 can be placed in a stacked state. The cutting table 4 is formed as a conveyor 7 in which bristle brushes 6 are densely arranged on the surface, and can transport the sheet material 5 placed thereon. The cutting table 4 has a rectangular planar shape, the transport direction as the conveyor 7 is defined as the X direction, and the width direction as the conveyor 7 perpendicular to the X direction is defined as the Y direction. The bristle brush 6 is formed by molding a synthetic resin material and has a block shape in which a plurality of bristles are implanted. The surface on which the sheet material 5 is placed on the cutting table 4 is formed by the bristles of the bristle brush 6. Since there is a gap between the bristles, the suction force generated from the suction box 3 acts on the lower surface of the sheet material 5. The sheet material 5 is introduced from one carry-in side in the conveyance direction of the conveyor 7, and is cut while the conveyor 7 is stopped and sucked on the cutting table 4. Performed on the unloading side.

  The cutting head 10 for cutting the sheet material 5 can be moved planarly along the surface of the cutting table 4 by the X-axis direction moving unit 11 and the Y-axis direction moving unit 12. The normal cutting order is set so as to start from the vicinity of the origin position provided at one corner of the carry-out side and end on the carry-in side. The X-axis direction moving unit 11 can reciprocate in the X-axis direction by supporting the Y-direction beam provided on the cutting table 4 in the width direction with guide rails provided on both sides. The Y-axis direction moving unit 12 can reciprocate the cutting head 10 in the Y-axis direction along the Y-direction beam. A cutting blade 13 hangs down from the cutting head 10 toward the surface of the cutting table 4. The cutting blade 13 is driven to reciprocate linearly in a certain amplitude range in the hanging direction. Further, the hanging state of the cutting blade 13 from the cutting head 10 can be controlled, the position where the tip of the cutting blade 13 is pulled up without reaching the surface of the sheet material 5, the sheet material 5 is pierced, and the tip is bristle A space between the brush 6 and the penetrating position can be taken. When the cutting blade 13 is driven to reciprocate in a state of penetrating into the bristle brush 6 to the tip, and the cutting head 10 is moved, the sheet material 5 can be cut. Even if the leading edge of the cutting blade 13 penetrates into the bristle brush 6, the bristle elastically deforms and escapes from the blade tip and returns to its original position when the cutting blade 13 moves, so that the sheet material 5 is supported by the leading edge of the bristle. State is restored. The surface of the sheet material 5 around the cutting blade 13 is pressed by the presser 14 so that the cutting blade 13 reciprocated during cutting does not lift the surface of the sheet material 5.

  If the sheet material 5 is a fabric or the like and has air permeability, a non-breathable synthetic resin sheet is covered as a covering sheet 15 in a state where a plurality of sheets are laminated. The covering sheet 15 can be placed on the surface of the sheet material 5 while carrying the laminated sheet material 5 onto the cutting table 4 by operating the conveyor 7. It is also possible to carry in a state in which the surface of the laminated sheet material 5 is covered with the covering sheet 15. The suction force by the suction box 3 acts to suck the cover sheet 15 to the surface of the cutting table 4. If the sheet material 5 is elastic, the laminated sheet material 5 is compressed to reduce its thickness. The presser 14 suppresses the sheet material 5 from above the covering sheet 15, and the cutting with the cutting blade 13 cuts the covering sheet 15 together with the sheet material 5. The pressing force with which the presser 14 holds the covering sheet 15 is set to be small compared to the suction force so that the cutting head 10 can be moved smoothly. When the covering sheet 15 is cut, ambient air enters from the cut portion, the suction force to the cutting table 4 is reduced, the compressed state is relaxed, the thickness of the sheet material 5 is increased, and the cutting is performed. The height of the surface of the sheet material 5 from the surface of the table 4 also increases. As the height of the surface of the sheet material 5 increases, the presser 14 also rises.

  An operation unit 16 is provided for an operator to give an operation instruction to the cutting machine 1 and the like. As will be described later, for example, a means for detecting the height of the presser 14 and adjusting the suction force of the suction block 3 so as to suppress the change is provided in the operation unit 16. Even if the cutting progresses and the air leakage increases by adjusting the suction force, the suction adjustment can be performed so that the suction force also increases, and the cutting accuracy can be maintained. In addition, in order to prevent leakage from the cutting part with the progress of cutting, the space between the carry-out side of the cutting table 4 and the cutting head 10 may be covered with a non-breathable sealing sheet. A mechanism for feeding the sealing sheet in conjunction with the movement by the X-axis direction moving unit 11 may be provided on the carry-out side of the cutting head 10. For example, as a disclosure of such a sealing sheet, JP-A-5-51865 can be cited.

  As described above, when the sheet material 5 is sucked and held on the cutting table 4 and is cut by the cutting machine 1 that moves the cutting blade 13 relative to the cutting table 4 according to preset data, the cutting is performed. Since the change in the height of the surface of the sheet material 5 on the table 4 is grasped, the state where the leakage increases as the cutting progresses and the surface height of the sheet material increases as the suction force decreases is grasped. be able to. Since the suction state is adjusted so as to compensate for the decrease in the holding force to the sheet material 5 due to an increase in leakage with the progress of cutting, the fluctuation in the height of the surface of the sheet material 5 sucked onto the cutting table 4 Even the sheet material 5 having elasticity can be cut in an appropriate compressed state.

  Further, when cutting the surface of the sheet material 5 while pressing the surface of the sheet material 5 with the presser 14 around the cutting blade 13, the change in the height of the surface is detected and grasped as the change in the height of the presser 14, so that the cutting is actually performed. It is possible to reliably detect and grasp the height of the surface of the sheet material 5 in such a state.

  FIG. 2 shows the configuration of the cutting head 10. The main part of the cutting head 10 is accommodated in the casing 20. In the casing 20, guide rods 21 and 22 extending in the vertical direction are arranged. The guide rods 21 and 22 guide the up-and-down displacement to a reciprocating drive mechanism 23 that generates a reciprocating motion of the cutting blade 13 by a crank mechanism or the like. Below the reciprocating mechanism 23, a sliding block 24 that can be displaced up and down along the guide rods 21 and 22 is disposed. The sliding block 24 is provided with a mechanism capable of changing the direction of the blade edge for cutting the sheet material 5 with the cutting blade 13 around the vertical R axis, and the presser 14 is disposed at the lower end. The sliding block 24 is urged downward by the elastic force of gravity or a spring. The sliding block 24 can be displaced up and down below the reciprocating drive mechanism 23 within a certain stroke range. The reciprocating drive mechanism 23 and the sliding block 24 can be raised by a cylinder not shown, and the tip of the cutting blade 13 and the presser 24 can be sufficiently separated from the surface of the cutting table 14. Further, the sliding block 24 keeps pressing the surface of the covering sheet 15 by the presser 14, while raising only the reciprocating drive mechanism 23, and pulling up the tip of the cutting blade 13 from the surface of the covering sheet 15. You can also.

  The cutting head 10 is also provided with means for detecting the position of the sliding block 24 that moves up and down. An L-shaped bracket 25 is fixed to the sliding block 24. A pinion gear 27 including a rotary encoder 26 is attached to the upper end of the bracket 25. The pinion gear 27 meshes with a rack 28 fixed to the casing 20 side. When the sliding block 24 is displaced up and down, the pinion gear 27 that is displaced along the rack 28 is angularly displaced, and the amount of elevation displacement can be detected by the rotary encoder 26 as the amount of angular displacement.

  FIG. 3 shows a schematic electrical configuration of the cutting machine 1 of FIG. The operation unit 16 includes a control unit 30, an operation input unit 31, a calculation unit 32, a storage unit 33, a display unit 34, a height detection unit 35, and the like. A data input unit 36, a head drive unit 37, and a suction unit 38 are provided in the base frame 2 or an independent control unit. Such a configuration is shown as an example only, and the operation unit 16 may include the operation input unit 31 and the display unit 34. Moreover, although the operation part 16 is provided in the X-axis direction moving part 11, it can also be provided in the base frame 2 or an independent control unit.

  The operation input unit 31 includes switches and keys. The display unit 34 includes a flat display such as a liquid crystal. At least a part of the operation input unit 31 and the display unit 34 can be integrated as a touch panel. The control part 30, the calculating part 32, and the height detection part 35 are each implement | achieved by the program operation | movement of CPU, for example. The storage unit 33 is realized by a memory such as a RAM. Detection data on the height of the sliding block 24 interlocked with the presser 14 is input from the rotary encoder 26 to the height detection unit 35.

  Data about the cutting of the sheet material 5 is input to the data input unit 36. This data is created by a design system or the like and is input via a recording medium such as a disk or via an information communication line. The input data includes position data such as contour lines of parts to be cut, part cutting order data, and the like. The cutting order may be input from the operation input unit 31 without being input from the data input unit 36. In addition, the data input from the data input unit 36 can be displayed on the display unit 34 so that the data can be confirmed, and the operation input unit 31 can correct or supplement the data.

  The head drive unit 37 includes an X-axis direction moving unit 11 and a Y-axis direction moving unit 12. The head drive unit 37 also includes a reciprocating drive mechanism 23 and a drive source for a mechanism that can change the direction of the cutting edge of the cutting blade 13 around the vertical R axis. Further, the head drive unit 37 includes a cylinder that drives the reciprocating drive mechanism 23 and the sliding block 24 up and down.

  The suction unit 38 includes a blower for generating a suction force in the suction box 3 and can adjust the suction force. The suction force can be controlled in a plurality of stages by, for example, inverter-controlling a motor such as a blower. It is also possible to perform the control continuously. In addition, a driving source such as a motor is driven in a constant state, and the suction force can be adjusted by a change in a throttle provided in a suction path such as an intake duct.

  FIG. 4 shows a plurality of parts 41, 42, 43, 44, 45, 46, 47, 48, 49,... From the original fabric 40 in a state where a plurality of sheet materials 5 are laminated and covered with the covering sheet 15. An example in which the position of the left corner on the carry-out side is set as the origin and cutting is performed in the order of the numbers. Although the parts 41, 42, 43, 44, 45, 46, 47, 48, 49,... Have the same shape for the sake of explanation, they are actually different in shape and are parts for improving the yield. , 41, 42, 43, 44, 45, 46, 47, 48, 49,. The numerical value described in the figure of each part 41, 42, 43, 44, 45, 46, 47, 48, 49, ... shows the set value of the suction force. The suction force is increased stepwise in the order of 1, 2, 3, 4,.

  It should be noted that the above-described sealing sheet is placed on the part of the cutting table 4 that has been cut out from the cutting head 10 on the carry-out side to prevent leakage from the cutting part. Therefore, in the process of sequentially cutting the first and second row parts 41, 42, 43, 44, 45, and 46 from the carry-out side, the suction force is also sequentially increased to 1, 2, 3, and 4. However, when the parts 47, 48, and 49 in the third row are cut, for example, the already cut parts 41, 42, and 43 in the first row are covered with the sealing sheet, so that the set value is low. When the sealing sheet is not used, the set value may be further increased when the parts 47, 48, and 49 in the third row are cut.

  FIG. 5 shows a schematic procedure until suction adjustment is performed in the present embodiment. The procedure is started from step a0, and the clothing and the like using the cut parts are designed. In step a1, for example, marking data for arranging parts 41, 42, 43, 44, 45, 46, 47, 48, 49,... On the original fabric 40 shown in FIG. Next, in step a2, the part cutting order is determined. Although the principle of the cutting order is to cut sequentially from the origin, it may be better to change the order depending on the shape of the parts. The creation of the marking data and the determination of the cutting order are performed by a design system or the like, and the creation result is input to the data input unit 36 in FIG. 3 as cutting data.

  Next, in step a3, when the sheet material 5 is loaded onto the cutting table 4 and held with suction force by an operation to the operation unit 16, and a cutting start instruction is input, the cutting by the control unit 30 in FIG. Control and suction adjustment procedures are started. In step a4, when the presser 14 is lowered to the cutting position of the first part and the bottom surface of the presser 14 comes into contact with the surface of the covering sheet 15, the height detector 35 sets the output value of the rotary encoder 26 as the height. It is detected and stored in the storage unit 33. In step a5, it is determined whether or not the detected height exceeds the management upper limit. If the height does not exceed the management upper limit, it is determined in step a6 whether or not the height has reached the management lower limit. When it is determined in step a5 that the height exceeds the management upper limit, the set value of the suction force is increased by one step in step a7. When it is determined in step a6 that the height has not reached the control lower limit or more, the set value of the suction force is decreased by one step in step a8. When it is determined in steps a5 and a6 that the height is not less than the control lower limit and not more than the control upper limit, or after the set value is increased or decreased in steps a7 and a8, in step a9, the data input unit Based on the data input to 36, it is determined whether or not the cutting is finished. When it is determined that the cutting is not finished, the process returns to step a4.

  Hereinafter, after cutting one part or when the cutting head 10 moves to the cutting position of the next part, the height of the surface of the covering sheet 15 is detected by the presser 14, and the suction force is determined according to the height. Change the set value of and adjust the suction. When cutting for all parts is completed according to the data input to the data input unit 36, it is determined in step a9 that cutting is complete, and in step a10, the conveyor 7 is driven so that the cut parts are sent to the carry-out side. To finish the procedure. Note that the length of the sheet material 5 in the X-axis direction is longer than the length of the cutting table 4 in the X-axis direction, and the uncut portion is carried onto the cutting table 4 as the already cut portion is carried out. You may repeat continuing cutting. Thus, if the adjustment of the suction state is performed for each cutting of a part whose contour to be cut is defined by data, each part can be cut accurately.

  FIG. 6 repeats the procedure from step a4 to step a9 in FIG. 5 to simplify an example of a change in height when performing suction adjustment while detecting the height of the surface of the sheet material 5 (a ) And the change in the corresponding set value of the suction force is shown in (b). When cutting is started from time t0, leakage increases as the cutting progresses, so that the surface height of the sheet material 5 detected by the presser 14 in contact with the cover sheet 15 also increases. When the surface height reaches the control upper limit at time t1, the set value of the suction force increases by one step. However, for example, even if the suction force of a blower or the like that sucks air in the suction box 3 is increased by inverter control, the pressure in the suction box 3 decreases, and the bristle of the bristle brush 6 passes through a suction passage such as a suction duct. It takes time until the influence of the increase in suction force reaches the surface of the cutting table 4 formed at the tip, and the surface height may increase until time t2. Therefore, the control upper limit is set lower than the surface height at which the cutting error is actually increased in consideration of the increase due to such a time delay. In addition, when using a sealing sheet etc., the surface height falls below the control lower limit, and it may be necessary to reduce the set value of the suction force.

  Further, the suction state can be adjusted at a timing when the tip of the cutting blade 13 is pulled up from the surface of the covering sheet 15. Even while cutting a single part, the cutting blade 13 may be pulled out once to change the direction of the cutting edge or restart cutting at a discontinuous position depending on the shape and position of the line to be cut. . If height detection and suction force adjustment are performed at each timing, the width between the management upper limit and the management lower limit can be narrowed, and the variation in height can be reduced. Furthermore, if the suction force can be continuously adjusted and the suction force is adjusted according to the height of the surface while cutting the sheet material 5, the height of the sheet material 5 being cut. It is possible to perform accurate cutting while suppressing the change of.

  FIG. 7 shows another embodiment of the present invention, in which the adjustment of the suction state is predicted based on the grasp of the change in the height of the surface, and the increase in leakage with the progress of cutting according to the data is predicted, and the increase in leakage is calculated. The procedure to be compensated by increasing the suction force is shown. Since the suction adjustment is performed based on the prediction of the surface height, the height of the surface of the sheet material 5 can be adjusted in accordance with the cutting even if there is a time delay in the adjustment of the suction force. Each step from step b0 to step b4 is the same as each step from step a0 to step a4 in FIG. The steps after step b4 are the same as the control procedure by the control unit 30 in FIG.

  In step b5, the height after the cutting process is predicted based on the change state of the detected value of the height and the cutting progress state. The cutting process follows the data input to the data input unit 36. The detected height value is stored in the storage unit 33. The prediction is based on the relationship between the distance actually cut up to that point and the increase in height, and the cutting speed is also taken into consideration. The height after the lapse of the delay time until the change occurs is predicted.

  Hereinafter, in steps b6 and b7, the same determination as in steps a5 and a6 in FIG. 5 is performed with respect to the predicted height. That is, in step b6, it is determined whether or not the predicted height exceeds the prediction upper limit. When it is determined that the predicted height exceeds the upper limit, the set value of the suction force is increased in step b8. In step b7, it is determined whether the predicted height does not reach the prediction lower limit. If it is determined that the predicted height does not reach the prediction lower limit, the set value of the suction force is decreased in step b9. When it is determined in steps b6 and b7 that the height is in the range of the prediction lower limit or more and the prediction upper limit or less, or after the set value is increased or decreased in steps b8 and b9, in step b10, the data input unit Based on the data input to 36, it is determined whether or not the cutting is finished. When it is determined that cutting is not completed, the process returns to step b4. If it is determined in step b10 that the cutting has been completed, in step b11, the conveyor 7 is driven to convey the cut parts to the carry-out side, and the procedure ends.

  FIG. 8 shows an example of a change in height when performing suction adjustment while predicting based on data obtained by detecting the height of the surface of the sheet material 5 by repeating the procedure from step b4 to step b10 in FIG. Is represented by (a), and a change in the corresponding set value of the suction force is represented by (b). When cutting is started from time t10, leakage increases as the cutting progresses, so that the surface height of the sheet material 5 detected by the presser 14 in contact with the cover sheet 15 also increases. If it is predicted at time t11 that the surface height will reach the prediction upper limit at time t12 after cutting progress, the suction force setting value is increased by one step. As described above, even if it takes time until the surface of the cutting table 4 is affected by the increase in the suction force, at time t12, the suction force can be increased and the height can be decreased.

  In each of the embodiments described above, the cutting head 10 including the cutting blade 13 is moved in accordance with preset data by the cutting machine 1 that sucks the sheet material 5 and holds it on the cutting table 4. When cutting the sheet material 5, the suction adjustment device of the cutting machine for adjusting the suction state includes a rotary encoder 26 that is a height detection unit and a control unit 30 that is a suction adjustment unit. Since the height detection means detects the height of the surface of the sheet material 5 on the cutting table 4, the leakage increases according to the cutting, and even if the height of the surface of the sheet material 5 increases, it can reliably detect the height. Change can be grasped. Since the suction adjustment means adjusts the suction state so that the height detected by the height detection means falls within a predetermined range with respect to the progress of the cutting, the sheet material 5 sucked onto the cutting table 4 is used. Even the sheet material 5 having elasticity and suppressing the variation in the height of the surface can be cut in an appropriate compressed state.

  Further, the cutting head 10 of the cutting machine 1 includes a presser 14 that presses the surface of the sheet material 5 around the cutting blade 13. The rotary encoder 26 serving as a height detecting means detects the change in the height of the surface of the sheet material 5 by detecting the height of the sliding block 24 provided with the presser 14 at the lower end, and thus actually cuts. It is possible to reliably detect and grasp the height of the surface of the sheet material 5 in the state.

  In addition, the structure which detects the surface height of the sheet material 5 on the cutting table 4 as the height of the presser 14 is not a combination of the pinion gear 27 and the rack 28, but is detected optically or magnetically in a non-contact manner. You can also do it. Further, the surface of the covering sheet 15 or the sheet material 5 is irradiated with a laser beam or the like in a non-contact manner such as a method of detecting the height of the surface based on a displacement of a position where the reflected light is received. It can also be detected.

1 is a perspective view showing a schematic external configuration of a cutting machine 1 that executes a suction adjustment method as an embodiment of the present invention. It is sectional drawing which shows the structure of the cutting head 10 of FIG. It is a block diagram which shows schematic electrical structure of the cutting machine 1 of FIG. It is a figure which shows the example which cuts several parts from the raw fabric 40 with the cutting machine 1 of FIG. It is a flowchart which shows the schematic procedure until it performs suction adjustment with the cutting machine 1 of FIG. By repeating the procedure from step a4 to step a9 in FIG. 5 and detecting the height of the surface of the sheet material 5, an example of the change in the suction adjustment and the change in the set value of the suction force are shown. It is a graph to show. It is a flowchart which shows the schematic procedure until it performs suction adjustment with the cutting machine 1 of FIG. 1 as another form of implementation of this invention. By repeating the procedure from step b4 to step b10 in FIG. 7 to detect the height of the surface of the sheet material 5, an example of the height change when performing the suction adjustment and the change in the set value of the suction force It is a graph to show.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cutting machine 3 Suction box 4 Cutting table 5 Sheet material 10 Cutting head 13 Cutting blade 14 Presser 15 Cover sheet 24 Sliding block 26 Rotary encoder 27 Pinion gear 28 Rack 30 Control part 32 Calculation part 33 Storage part 35 Height detection part 36 Data input part 37 Head drive part 38 Suction part 40 Original fabric 41, 42, 43, 44, 45, 46, 47, 48, 49, ... Parts

Claims (7)

A suction adjustment method when performing cutting with a cutting machine that moves the cutting blade relative to the table according to preset data while sucking and holding the sheet material on the table,
By grasping the change in the height of the surface of the sheet material on the table, the suction state is adjusted so as to compensate for the decrease in the holding force to the sheet material due to the increase in leakage as the cutting progresses The suction adjustment method of the cutting machine.   2. The suction adjustment method for a cutting machine according to claim 1, wherein the suction state is adjusted every time a part whose contour to be cut is defined by the data is cut.   The suction adjustment method for a cutting machine according to claim 1, wherein the suction state is adjusted according to the height of the surface while cutting the sheet material.   The adjustment of the suction state is performed based on grasping the change in the height of the surface, predicting an increase in leakage with the progress of cutting according to the data, and compensating for the increase by an increase in suction force. The suction adjustment method for a cutting machine according to claim 1. The cutting is performed while pressing the surface of the sheet material around the cutting blade with a presser,
5. The suction adjustment method for a cutting machine according to claim 1, wherein the change in the height of the surface is detected and grasped as a change in the height of the presser. A cutting machine for sucking and holding a sheet material on a table, and a cutting machine for adjusting a suction state when cutting a sheet material by moving a cutting head provided with a cutting blade according to preset data. A suction adjustment device,
A height detecting means for detecting the height of the surface of the sheet material on the table;
A suction adjustment device for a cutting machine, comprising: suction adjustment means for adjusting a suction state so that the height detected by the height detection means falls within a predetermined range with respect to the progress of cutting. The cutting machine includes a presser that presses a surface of a sheet material around the cutting blade on the cutting head,
The suction adjusting device for a cutting machine according to claim 6, wherein the height detecting means detects a change in height of the surface of the sheet material by detecting a height of the presser.

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