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(11) | EP 0 494 483 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Method for changing the direction of cutter edge of cutting plotter |
| (57) The present invention is to provide a method for changing the direction of a cutter
edge (52) of a cutting plotter, by which it is possible to change the direction of
the cutter edge (52) in case the surface of the effective plotting area (12) of a
sheet on a recording surface (20) is cut off by the above cutter (50) and also to
cut off accurately along straight line (16) as desired from the time when the cutting
of the area surface has been started. A cutter (50) having a main edge (52) with band-like
edge (52) directed diagonally upward being rotatable supported in a holder (56) around
its axial center (58), the edge of the cutter is directed toward a certain direction
by rotating the main edge (52) of the cutter in the holder (56), and that, when the
cutting of the surface of effective plotting area (12) of the sheet is started, the
edge of the cutter (52) directed toward a certain direction is pressed on the cut-starting
point on the surface of the effective plotting area (12), and by relatively moving
the pen carriage (40) over the sheet as if to depict a circular arc, the main edge
(54) of the cutter mounted on pen carriage is rotated in the holder (56) by a predetermined
angle, and the edge of the cutter is directed toward the direction to start the cutting
of the effective plotter area (12). |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a method for changing the direction of edge of a cutter mounted on pen carriage of a cutting plotter.
[0002] Conventionally, a so-called cutting plotter has been known, in which a cutter is mounted on a pen carriage, relatively moving in X-Y direction on a sheet placed on the recording plane.
[0003] In this plotter, the cutter mounted on pen carriage is arranged as shown in Fig. 7. Specifically, a main edge 54 having band-like edge 52 directed diagonally upward at its tip is rotatably supported within a holder 56 around its axial center 58. With the edge 52 of the cutter pressed on the sheet placed on the recording plane, the pen carriage with the cutter 50 is relatively moved in X-Y direction on the sheet. When the sheet surface is cut off, the main edge 54 of the cutter is rotated in the holder 56 around the axial center 58, and the edge 52 of the cutter is directed toward the cutting direction of the sheet.
[0004] In case the effective plotting area (the area on inner portion of the sheet to be used by the user) of the sheet placed on the recording plane is cut by the cutting plotter mounted with the above cutter, the surface of the area 12 where the cutting has been started is not cut off linearly as shown in Fig. 8 by the broken line 16, but it is cut off along curved line as given by solid line 18.
[0005] The reason for this is that, when the cutting is started on the surface of the above area 12, the edge 52 of the above cutter is not directed toward the cutting direction on the surface of the above area 12. Thereafter, when the surface of the area 12 is being cut by the above cutter 50, the main edge 54 of the cutter is rotated in the holder 56 around the axial center 58, and the edge 52 of the cutter is gradually turned toward the cutting direction of the surface of the area 12.
SUMMARY OF THE INVENTION
[0006] The object of the present invention is to provide a method for changing the direction of the cutter edge of a cutting plotter (hereinafter referred as "changing method"), by which it is possible to change the direction of the cutter edge in case the surface of the effective plotting area of the sheet on the recording surface is cut off by the above cutter and also to cut off accurately along straight line as desired from the time when the cutting of the area surface has been started.
[0007] To attain the above object, the first changing method according to the present invention comprises a cutter having a main edge with band-like edge directed diagonally upward being rotatably supported in a holder around its axial center, said cutter being mounted on a pen carriage relatively moving in X-Y direction over a sheet placed on the recording plane, and it is characterized in that, when the edge of said cutter is pressed on the surface of the sheet outside the effective plotting area of said sheet, said pen carriage is relatively moved toward the predetermined direction over the sheet and the surface of said sheet is cut off by the predetermined distance, and the edge of said cutter is directed toward a certain direction by rotating the main edge of said cutter in the holder, and that, when the cutting of the surface of effective plotting area of said sheet is started, the edge of the cutter directed toward a certain direction is pressed on the cut-starting point on the surface of said effective plotting area, and by relatively moving said pen carriage over the sheet as if to depict a circular arc, the main edge of said cutter mounted on pen carriage is rotated in the holder by a predetermined angle, and the edge of the cutter is directed toward the direction to start the cutting of the effective plotting area.
[0008] The second changing method of this invention comprises a cutter having a main edge with band-like edge directed diagonally upward being rotatably supported in a holder around its axial center, and said cutter being mounted on a pen carriage relatively moving in X-Y direction over a sheet placed on the recording plane, and it is characterized in that, a dead area where the edge of said cutter is pressed is furnished on a part of the recording plane outside the site where said sheet is placed, and when the edge of said cutter is pressed on this dead area, said pen carriage is moved in the predetermined direction over the dead area, and the edge of said cutter is directed in a certain direction by rotating the main edge of said cutter in the holder, and that, when the cutting of the effective plotting area of said sheet is started, the edge of the cutter directed toward a certain direction is pressed on the cut-starting point of said effective plotting area, and when the edge of the cutter directed toward a certain direction is pressed on the cut-starting point on said effective plotting area, said pen carriage is relatively moved over the sheet as if to depict a circular arc, and the edge of the cutter is directed toward the direction to start the cutting of the effective plotting area by rotating the main edge of said cutter mounted on pen carriage.
[0009] In the first and the second changing methods with such arrangement as described above, the edge of the cutter can be directed toward the direction to start the cutting of the effective plotting area when the cutting of the effective plotting area surface is started.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010]
Fig. 1 is a plan view of a vertical type cutting plotter to be used in the first changing method of this invention when sheet is placed on the recording plane of the plotter;
Fig. 2 is a partial enlarged view of the sheet of Fig. 1;
Fig. 3 is a side view schematically showing the structure of a vertical type cutting plotter to be used in the first and the second changing methods of this invention;
Fig. 4 is a drawing to explain the condition where the main edge of the cutter is rotated within the holder at the point to start the cutting of the sheet;
Fig. 5 is a plan view showing the moving route of the axial center of the main edge of the cutter of Fig. 4;
Fig. 6 is a plan view when the sheet is placed on the recording plane of vertical type cutting plotter to be used in the second changing method of this invention;
Fig. 7 is a front view of the cutter;
Fig. 8 is a plan view showing the condition when the surface of the effective plotting area of the sheet is cut off by the cutting plotter using the conventional method.
[0011] In the figures, 10 represents sheet, 12 an effective plotting area, 14 a sheet portion, 15 a point to start cutting, 20 a recording plane, 30 feeding means, 40 a pen carriage, 50 a cutter, 52 an edge, 54 a main edge, 56 a holder, and 60 a dead area.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0013] This plotter comprises a recording plane 20 having semi-cylindrical cross-section where the sheet 10 is placed, pinch roller 32 and driving roller 34 of the feeding means 30 to move the sheet 10 along the recording plane 20 in the front-back direction, i.e. in Y direction, a pen carriage 40 moving along the surface of said recording plane 20 in the left-right direction, i.e. in X direction, namely a pen carriage 40 provided with a cutter 50 cutting the surface of the sheet 10 and shown in Fig. 7, and lifting means (not shown) for lowering and pressing the cutter 50 mounted on said pen carriage on the surface of the sheet 10 placed on the recording plane 20 or for lifting it over the sheet 10.
[0014] Further, this plotter is provided with a CPU (central processing unit) for controlling the driving means (not shown), such as motor or actuator for driving said pen carriage 40, or feeding means 30, and with a computer (not shown) for issuing command to said CPU. According to the program inputted in the computer, said CPU is operated, and pen carriage 40, feeding means 30 or lifting means can be automatically controlled.
[0015] By this plotter, it is possible to cut the surface of the sheet 10 by the cutter 50 when pen carriage 40 is moved in X direction with the cutter 50 lowered and pressed on the surface of the sheet 10 on the recording plane 20 using the lifting means, and the cutter 50 is relatively moved in X-Y direction on the surface of the sheet 10 by moving the sheet 10 in Y direction over the recording plane 20 using the feeding means 30.
[0016] Next, detailed description is given on the method for cutting the sheet surface by the first changing method of this invention by operating CPU according to the program inputted in the computer, using this cutting plotter.
[0017] The edge 52 of main edge of the cutter mounted on pen carriage is lowered and pressed on the surface of the sheet 14 on outer portion of the effective plotting area 12 of the sheet placed on the recording plane 20. The pen carriage 40 is then relatively moved by the predetermined distance toward the desired direction (X direction in Fig. 1) over the sheet 10, and the surface of the sheet portion 14 is cut off by the desired length. Then, the main edge 54 of the cutter is rotated in the holder 56, and the edge 52 of the cutter is directed toward a certain direction (X direction in Fig. 1).
[0018] Next, with the cutter 50 lifted above the sheet 10 by the lifting means, pen carriage 40 is moved in X direction, and the sheet 10 is moved in Y direction over the recording plane 20 by the feeding means 30. The cutter 50 mounted on the pen carriage is positioned immediately above the cut-starting point 15 on the effective plotting area of the sheet. Next, the cutter 50 is lowered and pressed on the surface of the above cut-starting point 15 by the lifting means. With she edge 52 of the main edge of the cutter pressed on the surface of said cut-starting point 15, pen carriage 40 is moved in X direction by the predetermined distance, and the sheet 10 is moved in Y direction by the predetermined distance over the recording plane 20. By relatively moving the pen carriage 40 over the sheet 10 as if to depict a circular arc (Relative movement is zero in case the edge 52 of the cutter is directed toward the cut-starting direction on the surface of the effective plotting area 12 from the beginning.), the main edge 54 of the cutter mounted on pen carriage 40 is rotated by a desired angle within its holder, and the edge 52 of the cutter pressed on the surface of said cut-starting point 15 is directed toward to the direction start the cutting of the surface of said area 12.
[0019] With the edge 52 of the cutter pressed on the surface of the cut-starting point 15, pen carriage 40 is relatively moved over the sheet 10 as if to depict a circular arc, and the main edge 54 can be rotated by the desired angle within the holder 56 around the axial center 58. The reason for this is as follows: In Fig. 4, the main edge 54 of the cutter is laid down on the surface of the sheet 10. The tip of the band-like edge 52 directed diagonally upward of the main edge of the cutter is at the position eccentric to the axial center 58 of the main edge by the predetermined distance. Therefore, when the pen carriage 40 provided with the cutter 50 is relatively moved over the sheet 10 as if to depict a circular arc, with the tip of the edge 52 of main edge of the cutter pressed on the surface of said cut-starting point 15, the main edge 54 rotatably supported within the holder of the cutter is rotated by the desired angle around the axial center 58. The relative moving route of axial center of the cutter 50 and the axial center 58 of main edge in relation to the sheet 10 is as shown by broken line 17 in Fig. 5.
[0020] Then, pen carriage 40 is moved in X direction, and the sheet 10 is moved in Y direction over the recording plane 20 by the feeding means 30. With the edge 52 of main edge of the cutter mounted on pen carriage pressed on the surface of the effective plotting area 12 of the sheet, the surface of the area 12 is relatively moved in X-Y direction, and the surface of the area 12 can be cut off in the shape as desired.
[0021] In case the surface of the effective plotting area 12 is cut off as described above, the surface of the effective plotting area 12 of the sheet can be accurately cut off in the manner as desired along straight line because the edge 52 of main edge of the cutter mounted on pen carriage is directed toward the direction to start the cutting of the effective plotting area 12 from the time when the cutting is started.
[0022] In the above first changing method, when the surface of the sheet portion 14 outside the effective plotting area of the sheet is cut off, it is preferable to cut the surface of the sheet portion 14 by the edge 52 of main edge of the cutter in the form of elongated L-shape. The reason for this is as follows: In case the surface of the sheet portion 14 is cut off along straight line by short distance, the main edge 54 of the cutter is not completely rotated within the holder 56, and the cutting of the surface of the above sheet portion 14 by the cutter 50 is completed before the edge 52 of main edge is not completely directed toward the direction to cut the above sheet portion 14. Thus, it is not possible to direct the edge 52 of the cutter toward the direction as desired.
[0023] Fig. 6 shows a preferred embodiment of the cutting plotter to be used in the second changing method of this invention. It is a plan view when the sheet is placed on the recording plane. In the following, description is given on the embodiment in this figure.
[0024] The plotter in this figure is a vertical type cutting plotter, similar to the plotter of Fig. 3.
[0025] This plotter is provided with a planar dead area 60 made of urethane rubber, on which the cutter 50 on pen carriage can be repeatedly moved to the outer portion of the recording plane from the point where the sheet is placed with the edge 52 pressed on it.
[0026] Description is now given on the method to cut the sheet according to the second changing method of this invention by operating CPU according to the program inputted in the computer.
[0027] With the cutter 50 lifted above the sheet 10, pen carriage 40 is moved in X direction, and the pen carriage 40 is positioned immediately above said dead area 60. With the cutter on the pen carriage lowered and pressed on the surface of the dead area 60 by the lifting means, pen carriage 40 is moved by the predetermined distance along the surface of the above dead area 60 (X direction in the figure). By rotating main edge 54 of the cutter within the holder 56, the edge 52 of the cutter is directed toward a certain direction (X direction in the figure.).
[0028] Next, by the same procedure as in the first changing method, pen carriage 40 is moved in X direction with the cutter 50 lifted above the sheet 10. The sheet 10 is moved in Y direction along the recording plane 20, and the cutter 50 on pen carriage is positioned immediately above the cut-starting position on the effective plotting area 12 of the sheet. Further, by the same procedure as in the first changing method, the cutter 50 on pen carriage is lowered and pressed on the surface of the above cut-starting point by the lifting means, and pen carriage 40 is relatively moved over the sheet 10 as if to depict a circular arc. (The relative movement is zero in case the edge 54 of the cutter is directed foward the direction to start the cutting of the surface of the sheet 10 from the beginning.) Thus, the main edge 54 of the cutter is rotated within the holder 56 by the desired angle. Then, the edge of the cutter is directed toward the direction to start the cutting of the surface of the effective plotting area 12.
[0029] Thereafter, by the same procedure as in the first changing method, the cutter 50 is pressed on the surface of the effective plotting area 12, and pen carriage 40 is relatively moved in X-Y direction over the surface of the effective plotting area 12 of the sheet. Thus, the surface of the area 12 is cut off in the shape as desired.
[0030] Like the case of the first changing method as described above, according to the second changing method, the edge 52 of the cutter on pen carriage is directed toward the direction to start the cutting of the surface of the effective plotting area 12 from the time when the cutting of the surface of the effective plotting area 12 has been started. Accordingly, the surface of the above area 12 can be cut along a straight line as desired.
[0031] In the first and the second changing methods as described above, pen carriage is provided with a plurality of various types of cutters. It is needless to say that these methods can be applied to the cutting plotter, in which the cutter mounted on pen carriage can be automatically replaced with various types of cutters accommodated in the above pen magazine, or to the cutting plotter, in which the cutter mounted on pen carriage cannot be automatically replaced with various types of other cutters.
[0032] The first and the second changing methods of this invention can also be applied to the so-called horizontal type plotter, which comprises a wide and planar recording plane provided with sheet, a pen carriage moving in X-Y direction over said recording plane, i.e. a pen carriage provided with a cutter for cutting the sheet surface, and a lifting means for lifting and lowering the cutter on said pen carriage.
[0033] As described above, it is possible according to the first and the second changing methods of this invention to cut the surface of the effective plotting area of the sheet placed on the recording plane by the cutting plotter with the cutter mounted on pen carriage in the desired shape such as along straight line from the beginning.
1. A method for changing the direction of cutter edge of a cutting plotter, comprising
a cutter having a main edge with band-like edge directed diagonally upward being rotatably
supported in a holder around its axial center, said cutter being mounted on a pen
carriage relatively moving in X-Y direction over a sheet placed on the recording plane,
characterized in that, when the edge of said cutter is pressed on the surface of the
sheet outside the effective plotting area of said sheet, said pen carriage is relatively
moved toward the predetermined direction over the sheet and the surface of said sheet
is cut off by the predetermined distance, and the edge of said cutter is directed
toward a certain direction by rotating the main edge of said cutter in the holder,
and that, when the cutting of the surface of effective plotting area of said sheet
is started, the edge of the cutter directed toward a certain direction is pressed
on the effective plotting area, and by relatively moving said pen carriage over the
sheet as if to depict a circular arc, the main edge of said cutter mounted on pen
carriage is rotated in the holder by a predetermined angle, and the edge of the cutter
is directed toward the direction to start the cutting of the effective plotting area.
2. A method for changing the direction of cutter edge of a cutting plotter, comprising
a cutter having a main edge with band-like edge directed diagonally upward being rotatably
supported in a holder around its axial center, and said cutter being mounted on a
pen carriage relatively moving in X-Y direction over a sheet placed on the recording
plane, characterized in that, a dead area where the edge of said cutter is pressed
is furnished on a part of the recording plane outside the site where said sheet is
placed, and when the edge of said cutter is pressed on this dead area, said pen carriage
is moved in the predetermined direction over the dead area, and the edge of said cutter
is directed in a certain direction by rotating the main edge of said cutter in the
holder, and that, when the cutting of the effective plotting area of said sheet is
started, the edge of the cutter directed toward a certain direction is pressed on
the cut-starting point of said effective plotting area, and when the edge of the cutter
directed toward a certain direction is pressed on the cut-starting point on said effective
plotting area, said pen carriage is relatively moved over the sheet as if to depict
a circular arc, and the edge of the cutter is directed toward the direction to start
the cutting of the effective plotting area by rotating the main edge of said cutter
mounted on pen carriage.
3. A method for changing the direction of an edge (52) of a cutter (50) in a cutting
plotter, the cutter having a cutting tip for contact with the material to be cut,
and being mounted on a carriage (40) movable in first and second perpendicular directions
relative to a sheet (10) of material to be cut, and being rotatably supported in a
holder (56) around an axis having a component perpendicular to the first and second
direction such that the axis does not pass through the cutting tip, characterized
in that, before beginning to cut from a predetermined starting point (15) in a predetermined
cutting direction, the cutting tip is pressed on the sheet at the predetermined starting
point and, by moving said carriage relative to the sheet in a circular arc (17), the
edge of said cutter mounted on said carriage is rotated in the holder such that the
edge of the cutter is directed in the predetermined cutting direction.
4. A cutting plotter, including a cutter being mounted on a carriage and movable in first
and second perpendicular directions relative to a sheet of material to be cut, and
being rotatably supported in a holder around an axis having a component perpendicular
to the first and second directions, the cutter being controlled such that the direction
of an edge of the cutter is changed by a method as claimed in any preceding claim.