JPH032077B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for measuring the amount of error in the mounting position of a drawing pen in an automatic drawing machine that uses a plurality of drawing pens.

(Prior Art) Conventionally, a drawing device called a plotter or an automatic drawing machine has a drawing pen attached to the head.
By moving in the Y direction, the blueprint,
It is now possible to draw industrial designs, survey maps, or three-dimensional topographic maps.

In this case, when drawing in multiple colors or when drawing in several different line thicknesses, as shown in FIG. First, the desired drawing pen a is selected with arm b, and the head c is moved in the X-Y direction to draw a drawing, and then drawing pen a' is selected and drawn in the same manner.

However, when drawing pens a and a' are used interchangeably in this way, the positions of the tips of the individual drawing pens or the mounting positions with respect to arm b are slightly different, so it is necessary to set head c at the same coordinates on the X axis, for example. Even if set, the center position of the drawn line will be
If one position is a distance t from the head center o, the other position is t-s, which means that both drawing pens are deviated by the amount of deviation, that is, the error amount s.

In order to correct such errors, it is necessary to add correction control data to the CAD system that moves the head, but this error amount s is usually minute, and for example, It was about a fraction of that, and it was difficult to measure it accurately.

Conventionally, this error amount has been measured by placing the head in the same position, drawing while exchanging drawing pens, and visually observing the line deviation caused by each drawing pen, or by using a microscope. As shown in Figure 7, a magnifying glass f with a scale e
It was measured by.

In this case, in order to measure the amount of error, it is necessary to measure the distance from the center of each of the two lines g and h, for example, but since this distance is minute, accurate measurement is difficult. It was hot.

In addition, the measurement requires many years of experience and has the drawback of requiring time for adjustment.

(Object and structure of the present invention) An object of the present invention is to apply the relationship between the main scale and vernier scale in the measurement method and the principle of the vernier scale to a method for measuring the amount of error in the installation position of a drawing pen in an automatic drafting machine. The aim is to make it possible to easily and accurately measure the amount of error, and its feature is to use a drawing pen selected as a standard, and use a main scale that divides a predetermined interval from the standard line into n scales. Draw a line, and then, using another drawing pen, draw a line from the reference line position to the main scale line to make the predetermined interval n.
Draw a vernier line equally divided by ±1 scale, and select the position where the main scale line and the vernier line match as a reference by counting the scale of the main scale line or the vernier line from the reference line. It consists of a procedure for detecting the relative error between a drawing pen and other drawing pens.

(Example) The present invention will be described below with reference to FIGS. 1 to 5.
Although a detailed explanation will be given, since the automatic drawing machine used in the examples has a known configuration, the explanation will be brief.

1 in Fig. 1 is a head for holding a drawing pen of an automatic drafting machine, and is movable horizontally with respect to an axis 2 in the X direction and an axis 3 in the Y direction, which are supported by a frame (not shown). It is supported and is adapted to be automatically moved in the X-Y direction by a drive device (not shown) under the control of a computer (not shown).

The head 1 has a horizontal arm 4, and a forked drawing pen holder 4a at the tip of this arm 4 holds the shaft of the drawing pen _M0 vertically, and when it is released, another drawing can be performed. It works so that it can be replaced with a pen.

In addition to the drawing pen M ₀ , there are drawing pens M ₁ , M ₂ , M ₃ that have the same shape but differ in color or drawn line width.
... are prepared, and these drawing pens M ₀ , M ₁ ,
By replacing and using M _{2 .} . . , it is possible to draw lines of different colors or different thicknesses on the paper U.

FIGS. 2 and 3 show a method for measuring the amount of error in the installation position of a drawing pen. First, with a drawing pen _M0 serving as a reference, the origin of the X coordinate,
Draw a reference line R ₀ at ORGX ₀ , and from this reference line R ₀ ,
Main scale lines R ₁ , R ₂ . . . are drawn at pitches obtained by dividing the predetermined interval L into n equal parts (in this case, 10 equal parts).

Next, with another drawing pen M _X to be measured,
From the X coordinate origin, ORGX ₀ , draw vernier lines Q ₀ , Q ₁ , Q ₂ . line
R ₁ , R ₂ . . . partially overlap each other in the Y direction, or even if they do not overlap, almost no gap in the Y direction occurs. In this case, let P be the pitch difference between the main scale line and the vernier scale line.

Then, the main scale lines R ₀ , R ₁ , R ₂ ... and the vernier scale lines
Detect the position where Q ₀ , Q ₁ , Q ₂ , etc. match.

In Fig. 3, the main scale line R ₄ and the vernier scale line Q ₄ coincide at the mth scale (4th scale in this case) from the reference line R ₀ , so if the error amount is Δ _xo , Δ _xo =
P (pitch difference)×m. Also, if the origin coordinates of the drawing pen M _X to be measured are ORGX _o , then ORGX _o =
The relationship is ORGX ₀ + Δ _xo .

For example, L=11mm, n=10, p=0.1mm,
If m=4, the error amount Δ _xo =0.1×4=0.4 mm, and the relative error between the reference drawing pen and other drawing pens can be determined.

In the above embodiment, the scale of the main scale was n and the vernier scale was n+1, but the scale of the vernier was n-1.
You can also use it as

FIG. 4 X ₁ to _{X 6} shows an automatic drawing machine using six drawing pens M ₁ to _{M 6} to which the present invention is applied.
This figure shows a pattern when the relative error and offset amount Δd on the X axis of each drawing pen are measured.

In this example, the reference drawing pen
The main scale line R of M ₄ is shown as a solid line, and each drawing pen M ₁ ,
The vernier lines Q of M ₂ , M ₃ , M ₅ , and M ₆ are shown as broken lines.

Therefore, as mentioned above, the overlapping positions of each main scale line R and vernier scale line Q, indicated by (▼), are counted as (m) lines from the reference origin (ORGX ₀ = ORGX ₄ ). Therefore, if the pitch difference between the main scale line R and the vernier scale line Q is p, then the origin of each drawing pen M ₁ to _{M 6}
Each offset amount Δd of ORGX ₁ to ORGX ₆ = m×p
It can be found by

FIGS. 5, Y ₁ to _{Y 6} illustrate patterns when the relative error and offset amount Δd on the Y axis of each drawing pen in FIG. 4 are measured.

Similarly to FIG. 4, the main scale line R which is the origin (ORGY ₀ = ORGY ₄ ) of the reference drawing pen M ₄ is shown as a solid line, and each drawing pen M ₁ , M ₂ , M ₃ , M ₅ , M The vernier line Q of _{No. 6} is shown as a broken line.

The offset amount Δd of each origin ORGY ₁ to ORGY ₆ on the Y axis can be determined by Δd=m×p.

After calculating the offset amount Δd on the X and Y axes of each drawing pen M ₁ , M ₂ , M ₃ , M ₅ , M ₆ with respect to the reference drawing pen M ₄ in the above manner,
These are input into the head 1 control program as correction values.

After the correction, with the start of drafting work,
No matter which drawing pen M ₁ to _{M 6} is selected by arm 4,
Since the reference origins ORGX ₀ and ORGY ₀ and the origins of each drawing pen ORGX ₁ to ORGX ₆ and ORGY ₁ to ORGY ₆ are aligned, the drawing lines match without deviation.

(Effects of the Invention) According to the present invention, by applying the principle of the vernier scale, lines drawn by a drawing pen selected as a reference and other drawing pens are overlapped so as to have the relationship of a main scale line and a vernier scale line. Drawing has the advantage that the relative amount of error of each drawing pen with respect to the head can be easily measured.

Therefore, based on this measured amount, the origin coordinates of each drawing pen can be aligned with the reference origin coordinates, and the offset amount of the drawing pen can be easily and accurately adjusted in an automatic drafting machine, and the drawing pen can be automatically adjusted. Even if you replace it with a new one, there will be no line or color misalignment.

[Brief explanation of drawings]

FIG. 1 is a schematic front view of a drawing pen head used in carrying out the present invention, FIGS. 2 and 3 are line diagrams for explaining the measurement principle of the present invention, and FIGS. The figure is a diagram showing various patterns for explaining an embodiment of the present invention, FIG. 6 is a schematic front view showing a conventional automatic drawing machine, and FIG. 7 is a diagram showing a conventional error measurement method. FIG. 1...Head, 2, 3...Axis, 4...Arm,
4a...Drawing pen holder, _M0 to _M6 ...Drawing pen,
U... Paper, R, R ₀ ~ R ₁₀ ... Main scale line, Q, Q ₀ ~
Q ₁₀ ... Vernier line, ORGX ₀ ... X coordinate origin,
ORGY ₀ ...Y coordinate origin, ORGX ₁ ~ ORGX ₆ ...
Drawing pen X coordinate, ORGY ₁ to ORGY ₆ ...Drawing pen Y coordinate, Δd...Error amount (offset amount), p...
Pitch difference.

Claims (1)

[Claims] 1. In an automatic drawing machine in which a plurality of drawing pens are attached interchangeably to a head that can move relative to the paper, a main scale line is drawn by equally dividing a predetermined interval from the reference line in n scales using the drawing pen selected as a reference. Then, using another drawing pen, partially overlap the main scale line from the position of the reference line to draw the predetermined interval n.
Draw a vernier line equally divided by ±1 scale, and select the position where the main scale line and the vernier line match as a reference by counting the scale of the main scale line or the vernier line from the reference line. A method for measuring the amount of error in the mounting position of a drawing pen in an automatic drafting machine, characterized by detecting the relative error between a drawing pen and other drawing pens.