JP2630154B2 - Cutter head control method in cutting plotter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a cutter head of a cutting plotter for cutting an adhesive sheet or the like using a cutter blade.

[0002]

2. Description of the Related Art Conventionally, an eccentric center of rotation of a rotatable cutter mounted on a cutter head and a cutting edge of the cutter are used to caster action to follow the trajectory of the cutting edge as the cutter head moves. It is known from JP-A-2-15358. In the above prior art, when cutting two continuous line segments at a certain angle,
As shown in FIG. 9, with the cutter head lowered, the center of rotation of the cutter is on the extension of the first line segment α in the cutting direction, and corresponds to the eccentric amount D of the cutting edge from the end point of the line segment. After moving to the position P1 separated by a distance and cutting the first line segment α to the end point, the cutter rotation center P
Is moved from P1 on the extension of the first line segment α to P2 on the second line segment β by an arc movement having the eccentricity D as a radius around the cutting edge to change the direction of the cutter to the second line segment. In the method, the direction of β is made to coincide with the direction of β, and then the cutter is moved along the second line segment β to continuously cut the two line segments α and β. Therefore, at the refraction point where the two line segments α and β intersect, the entire cutter blade rotates in the horizontal direction around the blade edge, and the inclined surface toward the tip of the cutter blade squeezes the cutting material such as an adhesive sheet in the rotational direction. become,
When the angle of the two line segments is acute, the rotation angle (θ2) of the cutter blade is close to 180 degrees at the maximum, and the angle at which the cutter blade pryes the adhesive sheet increases. The layer may peel off.

[0003]

The pressure-sensitive adhesive sheet or the like cut off by a conventional cutting plotter may have difficulty in sharpening the corners and may cause a problem in finished quality. Also, the adhesive layer of the adhesive sheet may be damaged,
When the corners are deformed, there is a problem that the corners are easily peeled off due to intrusion of dust and water from the corners.

Accordingly, an object of the present invention is to improve the finish quality of the bent portion of the cut line, prevent deformation and damage of the cutting material, and improve the quality and durability of the final product. is there.

[0005]

SUMMARY OF THE INVENTION The present invention proposes the above-mentioned object, in which a cutter is rotatably mounted on a cutter head, and the cutting edge of the cutter is eccentric with respect to the center of rotation. In a cutting plotter that cuts a cutting material by making the cutting edge follow the movement of the cutter head, a driving unit that rotates the direction of the cutting edge viewed from the center of rotation of the cutter in a plurality of preset reference directions. At the time of cutting two continuous line segments, the cutter head is raised at the end point of the first line segment, and at the ascending position, the direction of the blade edge of the cutter is moved by the driving means in the reference direction closest to the second line segment. And move the cutter head so that the start point of the second line segment matches the cutting edge of the cutter. In the lowered position, the center of rotation of the cutter is moved from the reference direction line to the second line segment by an arc movement having the eccentric amount as a radius around the cutting edge of the cutter to move the cutter in the second direction. And controlling the cutter head so that the directions of the line segments coincide with each other.

[0006]

When the cutter blade cuts the first line segment to the end point, the cutter head rises, and in this raised state, the cutter blade moves to one of the plurality of reference directions closest to the direction of the second line segment to be cut. Rotated in one reference direction. By the movement of the cutter head, the starting point of the second line segment coincides with the blade edge of the cutter, and the blade edge lands at the starting point of the second line segment.

In this state, the rotation center of the cutter blade is circularly moved from the reference direction line to the second line segment about the blade edge, and the direction of the cutter blade coincides with the direction of the second line segment. Thereafter, the cutter is moved along the second line segment to cut two continuous line segments.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a cutter head 11, which is mounted on a head carriage of a cutting plotter (not shown) and is driven together with the head carriage on the drawing plate in the X-Y direction.
Is moved up and down to cut the cutting material.

The cutter head 11 contains a cutter holder 14 in an outer cylinder 13. Cutter holder 14
Has a cutter 17 mounted via an upper pivot bearing 15 and a lower radial bearing 16, and the cutter 17 is rotatable with respect to the cutter holder 14. The cutter 17 has a cutter blade 18 at the lower end, and a reflecting plate 19 for position detection,
20 and the magnet 21 are fixed. Also, 22, 23
Are coils fixed in a cylindrical holder 24 fixed to the lower end of the head mounting arm 12, and 25 and 26 are reflection type photo sensors.

FIG. 2 shows the arrangement of the coils 22, 23, 27, and 28. The conductors are wound around both ends of two arc-shaped yokes 29, 30 to form the coils 22, 23, 27, and 28, respectively. Coils 22 and 23 and 27 at both ends of yokes 29 and 30
And 28 are respectively connected in series. One yoke 29 is rotated by 90 ° with respect to the other yoke 30, and the coils 22, 23, 27, 28 are arranged on four sides around the magnet 21 provided on the shaft of the cutter 17. .

The magnet 21 attached to the cutter 17 has the S pole facing outward, and as shown in FIG.
Is directed in the same direction as the S pole. FIG.
When the middle right is set in the X direction (0 °) and the upper side is set in the Y direction (90 °), if a + current flows from the terminals a1 to a2, the magnet S
The pole is repelled by the coil 22 on the 0 ° side, and is attracted by the coil 23 on the 180 ° side opposite thereto, so that the cutter 17 comes to the rotational position shown in the figure and is cut in the X direction. Further, when the direction of the current is reversed, the cutting edge C of the cutter blade 18 is reversed in the direction of 0 °, and becomes a cutting state in the −X direction. Similarly, when a current flows from the terminal b1 to the terminal b2, a line segment in the Y direction can be cut,
If the current is reversed, cutting in the -Y direction becomes possible.

FIG. 3 shows the arrangement of the photosensors 25, 26 and 31, which are arranged at three positions at 90 ° intervals. Two reflecting plates 19 and 20 are fixed to the cutter 17 at different mounting angles by 90 °. Further, in the lower part of the outer cylinder 13, through holes 32, 3
2 and 32 are formed so that light can be emitted to the reflection plates 19 and 20 and the reflected light can be received.

Here, as shown in the figure, the reflecting plates 19 and 20 are turned 90 ° and 180 ° counterclockwise with respect to the magnet 21.
FIG. 4 shows the relationship between the rotational position of the cutter 17 and the detection signals of the photosensors 25, 31, and 26 when the cutter 17 is mounted at an angle of. If the outputs of the three photosensors 25, 26, and 31 are regarded as 3-bit signals, as shown in FIG.
It is 011 at 10, 90 °, 001 at 180 °, 100 at 270 °, and 000 outside these angles.

The 3-bit signal is input to a drive control unit of the cutter head 11 described later to detect whether or not the direction of the cutter 17 matches the designated reference position. Next, according to FIG. 5, the reference direction (0 °, 90 °, 180 °, 2
A procedure for generating a drive signal for controlling the direction of the cutter blade 17 to 70 °) will be described. In the figure, α is the first line segment, β
Is the second line segment, and the arrow indicates the cutting direction. Θ1 is an angle formed between the reference direction 0 ° and the second line segment β, and θ2 is an angle formed between an extension (indicated by a broken line) of the first line segment α and the second line segment β. It is.

First, the direction section A2 of the second line segment β in the 45 ° equally spaced sections 0, 1,... 7 is determined. A2 = INTEGER (θ1 / 45) Equation 1 The reference direction section B2 = 0, 1, 2, 3 of the second line segment β is obtained from A2 obtained by integer conversion.

B2 = INTEGER ((A2 + 1) / 2) MODULO 4... Equation 2 The calculated 0,1,2,3 of the reference direction section B2 are set to the reference direction angles 0 °, 90 °, 180 °, 270 °. Each corresponds. For example, when A2 = 7, from equation 2, ((7 + 1) / 2) ÷ 4 = 1... Remainder 0, so that B2 = 0 and the reference direction angle is divided into 0 °.

Next, a method of controlling the cutter head 11 will be described with reference to the flowcharts of FIGS. 6 and 7 and the operation explanatory diagram of FIG. In FIG. 8, P1, P2,...
8, C1, C2,... Indicate the position of the cutting edge C. When the cutting command is input (step 101), the direction of the cutter blade 18 in the standby state (elevated position) is indeterminate, so that the coils 22, 23, 2 shown in FIG.
When the electromagnetic drive mechanism is energized by the control unit 7 or 28, the directions P1 and C1 of the cutter blade 18 are changed to the reference direction P closest to the line segment α.
1 and C2 (step 102). The determination of the reference direction is obtained by the procedure shown in FIG. Here, the line segment α is regarded as a line segment to be cut next, and is treated as a second line segment.

Subsequently, the cutter head 11 is moved to move the cutter blade 18 to P2 and C3 in order to position the cutting edge C at the starting point S of the target line segment α (step 103), and the cutter head 11 is lowered to set the cutting edge. C is grounded (step 104). Then, the energization of the electromagnetic drive mechanism is stopped, the rotation of the cutter blade 18 is set to a free state, and the direction θ1 of the line segment α is set.
Does not coincide with the selected reference angle B2, the process proceeds from step 105 to step 106, where the rotation center P on the reference direction line is
Is moved on a line segment α by an arc movement with the radius of the eccentricity D between the cutting edge C and the rotation axis P with C3 as a fulcrum (P3, C
3) Therefore, the rotation angle of the cutter blade 18 is B
2 × 90 ° −θ1, which does not exceed 45 °.
If θ1 coincides with the reference angle, the process proceeds from step 105 to step 107 without performing the above-described circular motion. In step 107, the XY drive control unit drives the cutter head 11, cuts the line segment α, and stops at P4 and C4 after moving the line segment length.

If there is no other continuous line segment connected to the line segment α for which the cutting process has been completed, steps 108 to 10
In step 9, the cutter head 11 is raised, and moved to the next line segment start position or standby position. If there is another continuous line segment β, the intersection angle θ2 with the extension of the immediately preceding line segment α is determined (step 110). When θ2 is 45 ° or more,
That is, when the rotation angle of the cutter blade 18 becomes 45 ° or more, the cutter head 11 is raised to separate the cutting edge C from the cutting material (step 111). And
Returning to step 102, the cutter blade 18 is rotated to the P4 and C5 positions based on the reference direction determination procedure described above. Thereafter, in step 103, the cutter head 11 is moved to the positions P5 and C4, and the cutter head 11 is lowered (step 10).
4), in the example shown in FIG. 8, the line segment β is cut into P6 and C4 in the processing of the next step 106 (step 10).
7).

Although not shown, if the intersection angle of the two lines is less than 45 °, steps 110 to 112 are performed.
Then, as in the prior art, the rotation axis P is moved from the extension of the previous line to the next target line by an arc motion having the eccentricity D as the radius around the cutting edge C, and then proceeds to the cutting process. . As described above, when the angle of the immediately preceding line segment and the next target line segment following the previous line segment are equal to or more than a predetermined angle (45 ° in this case), the cutter head 11 is once raised, and the direction of the cutter blade 18 is changed. After rotating to the reference angle closest to the direction of the target line segment, the cutting edge is lowered to the start position of the next target line segment, and cutting is started with the direction of the cutter blade 18 coinciding with the direction of the next line segment. Therefore, when the reference angle of the present embodiment is set at 90 ° intervals, at the time of cutting, the angle at which the cutting edge penetrating into the adhesive sheet material rotates to pry the adhesive sheet material is 45 ° at the maximum.
Therefore, deformation and damage of the cutting material at the refraction portion of the line segment can be prevented.

When the line segment data to be cut is a sign sheet of square gothic characters or the like, since the cutting direction of the line segment is often a right angle direction, it is not necessary to perform an arc motion and no twisting occurs. Therefore, the finish of the corner is improved. Note that the present invention is not limited to the above embodiment, and the number of divisions of the circumferential section B2 by the cutter head rotating mechanism can be variously set, and the present invention extends to those modified examples. Is natural.

[0022]

Since the present invention is configured as described in detail in the above embodiment, the amount of twisting of the cutting material by the cutting edge at the start point or the refraction point of the line segment can be reduced as much as possible. Accordingly, cutting accuracy is improved, and a high-quality finish can be obtained. In addition, since deformation due to kinking hardly occurs at the corners of the pressure-sensitive adhesive sheet or the like, it is possible to eliminate the possibility of a reduction in the adhesive force due to the deformation, and to improve the quality and durability of the cut product.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a cutter head used in a control method of the present invention.

FIG. 2 is a view taken along the line AA of FIG. 1;

FIG. 3 is a view taken along line BB of FIG. 1;

FIG. 4 is a correspondence table between directions of cutter blades and outputs of photo sensors.

FIG. 5 is a chart used in a calculation formula for determining a reference angle.

FIG. 6 is a first half of a flowchart of direction control of the cutter blade.

FIG. 7 is a second half of the flowchart of FIG. 6;

FIG. 8 is an explanatory diagram showing a locus of a cutter blade.

FIG. 9 is an explanatory view of a conventional cutting method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Cutter head 14 Cutter holder 17 Cutter 18 Cutter blade 19, 20 Reflector 21 Magnet 22, 23, 27, 28 Coil 25, 26, 31 Photosensor α, β line segment C Blade edge P Rotation center

Claims (1)

(57) [Claims] 1. A cutting plotter for rotatably mounting a cutter on a cutter head, eccentrically setting the cutting edge of the cutter with respect to the center of rotation, and cutting the cutting material by following the cutting edge with the movement of the cutter head. In the above, a driving means for rotating the direction of the blade edge viewed from the rotation center of the cutter in a plurality of preset reference directions is provided, and at the time of cutting two continuous line segments, the cutter at the end point of the first line segment The head is raised, and at the raised position, the direction of the blade edge of the cutter is rotated by the driving means in the reference direction closest to the second line segment, so that the starting point of the second line segment matches the blade edge of the cutter. Move the cutter head, and then lower the cutter head. At the lowered position, the rotation center of the cutter is centered on the cutting edge of the cutter. And moving the cutter head from the reference direction line to the second line segment by an arc motion having the eccentric amount as a radius to control the cutter head so that the direction of the cutter matches the direction of the second line segment. Cutter head control method in a cutting plotter.