JPH04197697A - Pen controller of plotter - Google Patents

Abstract

PURPOSE:To control a pen speed in moving a pen down in accordance with a change in the state of the pen to perform a high-speed plotting by a method wherein a speed pattern in moving the pen down is changed and determined in accordance with the acceleration change of the pen when it moves down to come into contact with a recording surface. CONSTITUTION:When a pen down instruction is detected from a setting signal UD of a pen down/up setting signal generation part 2, a speed pattern in moving a pen down is read from a speed pattern generation part 6, a height position setting signal in moving the pen down is outputted from a height position setting signal generation part 41, and a sequence in moving the pen down is executed. Next, a peak hold output of an acceleration signal AC in moving the pen down is detected by an impact value detection circuit 53. The detected impact value is compared with an appropriate impact value. If a need for changing the speed pattern is discriminated, the speed pattern stored in the speed pattern generation part 6 is corrected in accordance with a difference between the appropriate impact value and the detected impact value in a correction pattern forming part 5. This corrected speed pattern is registered as a pen-down sequence.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a pen control device for a drawing device, and more particularly to control of the moving speed of the pen when the pen tip is brought into contact with the recording surface from a state where it is separated from the recording surface.

[Conventional technology]

For example, XY blocks and drawing machines are known that automatically draw a desired drawing by moving a pen relatively over a recording surface, for example, a recording paper surface, in response to a drawing command from a computer. In this type of plotting device, the factors that determine the plotting time include the pen's travel time in the direction parallel to the recording paper surface, and the time required to move from one plotting end point to the next plotting starting point. The time required to raise and lower the pen occupies a relatively large amount of weight. For this reason, when controlling a pen that requires high-speed response, conventionally, when the pen tip is brought down from a state where it is separated from the recording paper and brought into contact with the recording paper surface, the impact and rebound of the pen tip on the recording paper surface is Taking these factors into consideration, control is performed using a speed pattern with a constant descent characteristic that allows for as fast a response as possible. That is, a control method is used in which the pen tip is lowered at high speed at the initial stage of pen down, and then lowered slowly near the recording paper surface to suppress the impact, and the pen tip is caused to land softly on the recording paper surface.

[Invention or problem to be solved]

In order to determine the speed pattern of pen control when the pen is down, it is necessary to particularly consider the impact value (impact load) when the pen tip contacts the recording surface. That is,
This is because if the impact value at the time of contact is large, the pen tip is likely to be damaged, and the recording paper may also be damaged. However, in many drawing devices such as X-Y plotters, multiple types of pens such as mechanical pencils, felt-tip pens, ink pens, and ballpoint pens can be used interchangeably. The magnitude of the above-mentioned impact value varies depending on the type of these pens, and even among pens of the same type, variations in pen weight,
It varies depending on the amount of ink remaining, the type of paper, etc. For example, in an ink pen, the impact value when the pen is down changes depending on the remaining amount of ink, the thickness of the pen, the wear of the tip of the pen, and the type of paper. In a water-based ballpoint pen, the impact value when the pen is down changes depending on the amount of ink remaining, variations in the length of the pen tip, and the type of paper. For mechanical pencils, the impact value when the pen is down changes depending on the shape change due to wear of the mechanical lead, the type of paper, etc. In this way, the impact value (impact load) when the pen is down is not constant, but changes depending on various factors. However, as mentioned above, conventionally, speed control during pen down is performed using a speed pattern with a constant descending characteristic.
That is, even at the maximum impact value, it is necessary to set the speed to be suppressed in order to reduce the impact on the pen and recording paper. For this reason, conventionally, it has not been possible to control the speed when the pen is down in accordance with changes in the pen type or state of the pen, which has been a hindrance to high-speed drawing. SUMMARY OF THE INVENTION In view of the above points, it is an object of the present invention to provide a pen control device that can control the speed when the pen is down in accordance with the type of pen, changes in the state of the pen, recording paper, etc.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a drawing device that holds a pen and includes a pen drive means that brings the pen tip into contact with and separates from the recording surface, when the pen tip contacts the recording surface. an acceleration detecting means for detecting the moving acceleration of the pen tip, and based on the output of the acceleration detecting means, a moving speed pattern when the pen tip is brought into contact with the recording surface from a state where the pen tip is separated from the recording surface is determined. A pen control device for a drawing device is provided.

[Effect]

The impact value when the pen tip contacts the recording surface corresponds to the movement acceleration of the pen tip at that time. Therefore, the speed pattern that is controlled and created based on the acceleration of the pen tip when it contacts the recording surface detected by the acceleration detection means is
This corresponds to the above-mentioned impact value, and enables high-speed control when the pen is down.

【Example】

Hereinafter, one embodiment of a pen control device according to the present invention will be described with reference to the drawings. FIG. 1 shows a block diagram of one embodiment of a pen control device according to the present invention. In addition, in this Figure 1, each main part can be configured as computer software.
In that case, each part represents a function executed by the computer as a block. That is, drawing data is supplied to the pen-down/up setting signal generating section 2 via the terminal 1, from which a pen-down/up setting signal UD consisting of a rectangular wave as shown in FIG. 2A is obtained. This bend down/up setting signal UD
The rising edge of indicates pen-up, the falling edge indicates pen-down, and the high level state corresponds to the horizontal movement distance in the pen-up state, and the low-level state corresponds to the horizontal movement distance in the pen-down state. It is adapted to the following. This pen down/up setting signal UD is supplied to the speed setting signal generating section 3. The speed setting signal generating section 3 generates an impact value (corresponding to the peak value of acceleration) at the time of contact between the standard pattern generating section 4 of the speed pattern and the recording paper surface of the pen tip when the pen is down, as described later.
A modified pattern forming unit 5 that modifies the speed pattern according to
, a speed pattern generation section 6 composed of, for example, a RAM, which registers the speed pattern corrected by the corrected pattern forming section 5, and a pattern readout control section 7. The standard pattern generating section 4 of this speed setting signal generating section 3 is as follows:
For example, it is composed of a ROM, and has registered (stored) a standard speed pattern (for example, see FIG. 2B) depending on the type of pen. This standard pattern is such that the pattern when the pen is up may be the same regardless of the pen type, or the pattern when the pen is down is a standard pattern that has an appropriate impact value depending on the pen type. It varies depending on the This standard pattern generator 4 has a pen type selection number 1.5' SE which is obtained through a terminal 8 when replacing the pen.
is supplied, and a standard speed pattern corresponding to the pen type is read out from the second standard pattern generating section 4. Prior to the start of the f'1 diagram, the pattern readout control section 7 reads out the standard pattern of the speed pattern corresponding to the pen type from the standard pattern generation section 4 to which the pen type selection signal SE is applied, and uses the standard pattern as the standard pattern. The turn is registered in the speed pattern generator 6. At the start of drawing, the speed pattern registered in the speed pattern generation section 6 is read out in response to the pen down/up setting signal UD, and is used as the speed setting signal output from the speed setting signal generation section 3. Even during the drawing operation, the speed pattern data of the speed pattern generation section 6 is transmitted to the correction pattern formation section 5 as described later.
The speed pattern data is rewritten with the corrected speed pattern data. The speed setting signal v5 from the speed setting signal generating section 3 is supplied to the speed control section 9, and the speed control signal (servo signal) from this speed control section 9 is supplied to the actuator 10 as a pen up and down driving means. The speed of the recording paper is controlled during up and down. In this example, the actuator 1o is a linear actuator (
(described in detail in Japanese Patent Publication No. 63-18431) is used. The actuator 10 is provided with a movement speed detecting means for vertical movement of the pen, as will be described later, and its speed detection signal DV is supplied to the speed control section 9. and,
Using the speed control loop thus formed, the speed control section 9 performs servo control so that the speed of vertical movement of the pen corresponds to the speed setting signal. The output signal UD of the pen down/up setting signal generating section 2 is also supplied to the pen height position setting signal generating section 41. The pen height position setting signal generation section 41 can be configured with a ROM that stores in advance the pen height position setting signal H3 when the pen is up and when the pen is down. The height position setting signal H5 read out in response to the pen down/up setting signal UD from the height position setting signal generating section 41 is supplied to the position control section 42. On the other hand, as will be described later, the actuator 1o is provided with means for detecting the height position of the pen relative to the recording paper surface, and a height position detection signal DH thereof is supplied to the position control section 42. Then, the position control section 42 servo-controls the actuator 1o so that the height position detection signal DH indicates the height position set by the height position setting signal H5. The pressure control unit 43 receives the signal UD from the pen-down amplifier setting signal generation unit 2, the speed detection signal DV and the height position detection signal DH from the actuator]0, and
In response to the pen pressure setting signal from the pen pressure setting unit 44, the pen pressure setting unit 44 determines how far the pen is moved from the pen down state, the height position is zero, and the speed is zero (the state where the pen tip is in contact with the recording paper). Furthermore, the pen pressure is determined by whether it is forcibly lowered, and a control signal for this purpose is supplied to the actuator to control the pen pressure. In this case, the actuator 10 is provided with an acceleration sensor that detects the acceleration when the pen moves up and down, and the acceleration signal AC that is the sensor output is sent to the amplifier 51.
The acceleration signal is supplied to the peak hold circuit 52 via the acceleration signal, and the peak value of the acceleration is held. The output AC of the acceleration sensor is, for example, as shown in FIG. 2 E or F. Fig. 2 E shows the acceleration signal AC when the pen is in the pen or felt-tip pen, for example, when the speed pattern when the pen is down is the standard speed pattern (see Fig. 2 B), and Fig. 2 F shows the acceleration signal AC when the pen is down. It shows the acceleration signal AC when it is an ink pen. As is clear from FIG. 2 E and F, when the pen tip contacts the recording paper surface when the pen is down, the acceleration signal AC
indicates a peak value, and the peak value corresponds to the impact value when the pen tip contacts the recording paper surface. Therefore, the output of the peak hold circuit 52 corresponds to the impact value. The output of this peak hold circuit 52 is supplied to an impact value detection circuit 53, where the impact value is detected and compared with an appropriate impact value. This comparison output is supplied to the correction pattern forming section 5 of the speed setting signal generating section 3. Then, when the shock value detection circuit 53 detects that the output of the peak hold circuit 52 is larger than the appropriate shock value, the correction pattern forming section 5 changes the speed value registered in the speed pattern generation section 6. Read the turn and make the impact value smaller.
That is, the speed pattern is corrected so that the pen tip slowly contacts the recording paper, and this correction, <turn, is rewritten in the speed pattern generating section 6 and registered. In addition, when the output of the peak hold circuit 52 is small enough to accommodate an appropriate impact value, the impact detection circuit 53 reads out the speed pattern registered in the speed pattern generation section 6 and determines when the pen is down. The speed pattern is corrected to a speed pattern in which the speed becomes faster (the impact value becomes larger), and this corrected pattern is rewritten in the speed pattern generation section 6. In this case, the position detection signal DH from the actuator 10 obtained when the speed pattern or the standard pattern is
Assuming that the speed pattern is as shown in Figure 2B, if the speed pattern is modified so that the impact value is smaller, then
The position detection signal DH becomes as shown in FIG. 2C, and
When the speed pattern is modified so that the speed becomes faster when the pen is down, it becomes as shown in the second diagram. For example, even when drawing with the same type of pen, the output of the peak hold circuit 52 changes due to changes in the shape of the tip such as wear of the pen tip, changes in the amount of ink remaining, etc. It is possible to correct writing conditions such as pen pressure. In this example, the output of the impact value detection circuit 53 is supplied to the pen pressure setting section 44, and when the output of the peak hold circuit 52 becomes larger or smaller with respect to the appropriate impact value, , is corrected according to the pen pressure setting value of the pen pressure setting section 44 or the impact value. In addition, in the case of pen types such as ink pens and water-based ballpoint pens, where the pen weight changes relatively large depending on the amount of ink remaining,
The output of the peak hold circuit 52 is sent to the remaining ink amount detection circuit 6.
1, the remaining amount of ink is detected from the change in the peak value, and the remaining ink amount is displayed on the remaining ink amount display section 62. Note that the remaining ink amount detection circuit 6] and the remaining ink amount display section 62 are controlled by the pen type selection signal SE from the terminal 8, and these circuits 61 and 62 or the remaining ink amount display unit select the appropriate pen type. Only when it is to be driven. Further, the acceleration detection signal AC from the amplifier 51 is supplied to a pen contact point detection circuit 54. The point at which the acceleration or peak when the pen is down changes significantly is the point at which the pen tip contacts the recording paper, so the pen contact point detection circuit 5
Fourth, by detecting a change in the acceleration detection signal AC from the amplifier 51, it is possible to detect the point in time when the pen tip contacts the recording paper. Information on this contact point is then supplied to the contact position detection circuit 55, and the position detection signal DH from the actuator 10 at the detected contact point is referred to, thereby accurately detecting the contact height position. and,
Information on the detected contact height position is supplied to the position control section 42 and used as a reference for height position control. Conventionally, the contact position of the pen tip with respect to the recording paper is obtained by reading (sampling) the position detection signal DH from the actuator 10 after the pen is down based on the change in the contact position of the signal (current or voltage) applied to the actuator. That's what I was doing. However, this detected position was slightly different from the position where the pen tip contacted the recording surface. This is because there is bounce of the pen or deformation of the pen tip and recording medium. For this reason, in the past, when the height position was controlled based on the contact position between the recording paper surface and the pen, accurate control could not be achieved. On the other hand, in this example, as mentioned above, the contact point detection circuit 54 detects that the acceleration detection signal AC changes significantly at the point of contact with the recording surface of the pen tip, and the contact position detection circuit 55 detects At the time of contact, the position detection signal DH from the actuator 10 is sampled to detect the contact position, so that the contact position can be accurately grasped and the height position can be controlled accurately. An example of the actuator 10 used in the above example is shown in the third example.
It is shown in FIG. 4, which is a sectional view taken along line A-A in FIG. This actuator 10, as shown in FIG.
．． Second. It has a magnetic circuit forming device consisting of third and fourth permanent magnets 11, 12, 13 and 14. That is, the first and second permanent magnets 11 and 12 are provided above and below with their magnetic poles different from each other, and the first and second permanent magnets 11 and 12
and second permanent magnets 1] and 12 with upper space] 7 and lower space] 8 open and facing each other, third and fourth permanent magnets 13 and 14, or similar to the first and second permanent magnets. To,
They are placed one above the other with different magnetic poles. The first permanent magnet 11, the upper space 17, the third permanent magnet] 3, the fourth permanent magnet 14, the lower space 18, the second
A closed magnetic circuit consisting of permanent magnets 12 is formed. and a second portion 19b located in the upper space 17 and facing the first portion 19a.
The drive coil 19 is located in the lower space 18, or the spaces 17, 1 formed by these four permanent magnets 11-14.
．． 8. A moving member 21 to which a pen 22 is attached is coupled to this drive coil 19. A pen can be attached to and detached from the moving member 21, and a plurality of types of pens can be attached to and detached from the moving member 21. When replacing the pen, the pen selection signal SE is obtained from the pen identification means provided on the moving member 21. The movable member 21 is movably supported by a lever 24 that engages with a slide bearing 23 so as to move up and down within a predetermined range, and is guided by a guide member 25. Note that the coil spring 26 disposed between the movable member 21 and the fixed member 27 moves the movable member 21 to the fully raised position.
28 is a stopper for stopping the moving member 21 at the fully raised position. In addition, 3
5 is recording paper. In this actuator] 0, two height position detectors made of Hall elements are fixed to the hollow portion 30 of the coil 19. This height position detector 29
．． The height position is detected by detecting the direction and strength of the magnetic field in 18, and a position detection signal DH is output. Further, a speed detection coil 32 is provided coaxially around the outer periphery of the drive coil 19. This speed detection coil 32 includes
Since a voltage corresponding to the moving speed of the drive coil] 9 is generated, the speed detection coil 32 detects the speed from the change in this voltage and outputs a speed detection signal DV. And this actuator] 0 height position detector 29
The position detection signal DH from the speed detection coil 32 and the speed detection signal DV from the speed detection coil 32 are supplied to the drive control section 34 including the position control section 42 and the speed control section 9 described above. and,
A drive current controlled by the drive control unit 34 is supplied to the drive coil 19 via the drive circuit 20 to control the vertical movement of the moving member 21 and therefore the pen 22. In addition, in this example, an acceleration sensor 33 is attached to the moving member 2, and the output AC of this acceleration sensor 33 is supplied to the peak hold circuit 52 via the amplifier 51 as described above. . Note that instead of providing the acceleration sensor 33, the acceleration signal may be obtained by differentiating the speed detection signal DV of the speed detection coil 32 using a differentiating circuit. Next, with reference to the flowcharts of FIGS. 5 and 6, an explanation will be given of the operation of correcting and setting the speed pattern when the pen is down in accordance with the pen type and writing conditions. First, as shown in FIG. 5, when a pen type is selected prior to drawing, a signal SE indicating the pen type is read (step 101), and the standard pattern generator (for example, RCli) 4 reads the signal SE. The speed pattern corresponding to the pen type is compared with a standard pattern (step 102). The read standard pattern is then written into the speed pattern generating section (for example, RAM) 6 and registered (step 103). When a pen down command is detected from the setting signal UD from the pen town up setting signal generating section 2 (step 104), the pen down time is read out (step 05). That is, the speed pattern when the pen is down is read out from the speed pattern generating section 6, and the height position setting signal when the pen is down is output from the height position setting signal generating section 41. Then, this pen-down sequence is executed (step 106). Next, the peak hold output of the acceleration signal AC when the pen is down is detected by the impact value detection circuit 53 (step 107). Then, the detected impact value is compared with an appropriate impact value, and it is determined whether it is necessary to change the speed pattern (step 108). As a result of the determination, if it is determined that a change is necessary, the speed pattern generator 6
The speed pattern stored in the modified pattern forming section 5 is modified according to the difference between the appropriate impact value and the detected impact value (step 109). This modified speed pattern is then registered as a pen-down sequence in the speed pattern generator 6 (step 110). As a result of the determination in step 108, if it is determined that no change is necessary, the speed pattern of the speed pattern generator 6 is left unchanged (step 111). This is followed by a flowchart of the drawing operation, followed by a flowchart of the pen-up operation. Then, when a pen down command is detected again from the setting signal UD from the pen down/up setting signal generation section 2 (
Step 201), the pen-down sequence is read out in the same way as described above (step 202), and this pen-down sequence is executed (step 203). Then, the peak hold output of the acceleration signal AC when the pen is down is detected by the impact value detection section 53 (step 204). The detected impact value is then compared with an appropriate impact value, and it is determined whether the speed pattern needs to be changed (step 205). As a result of the determination, if it is determined that a change is necessary, the speed pattern generator 6
The speed pattern stored in the modified pattern forming section 5 is modified according to the difference between the appropriate value of the impact value and the detected impact value (step 206). This modified speed pattern is then registered as a pen-down sequence in the speed pattern generation section 6 (step 207). As a result of the determination in step 205, if it is determined that no change is necessary, the speed pattern of the speed pattern generator 6 is left unchanged (step 208). As described above, the impact value when the pen tip contacts the recording paper is detected by detecting the movement acceleration of the pen when the pen is down, and the pen type and pen status changes are determined according to this impact value. It is possible to obtain an appropriate speed pattern according to the pen, and high-speed response when the pen is down is possible. In addition, stable drawing quality can be achieved by changing not only the speed pattern when the pen is down but also writing conditions such as writing pressure in accordance with changes in the acceleration signal. Furthermore, since it is possible to estimate the remaining amount of ink from the acceleration signal, it is possible to control the writing pressure, writing acceleration, writing speed, etc. after the pen is down in response to changes in drawing density in ink pens, etc. Therefore, it is possible to further stabilize the drawing quality. In the above embodiment, the speed pattern when the pen is down is corrected (calculated) according to the detected impact value, but it is also possible to prepare in advance a ROM, for example, that stores a plurality of speed patterns when the pen is down. Then, depending on the detected impact value, the speed pattern read from this ROM may be changed from the previously used pattern. In addition, in the above example, focusing on the peak hold output of acceleration, and using the fact that this peak hold value corresponds to the impact value when the pen tip contacts the recording surface, the velocity pattern is However, as shown in Figure 2 E and F, the acceleration pattern changes depending on the pen type, so when the pen tip collides with the recording surface, the It is also possible to detect an acceleration pattern and, in response to changes in this acceleration pattern, to set a speed pattern that immediately corresponds to the writing conditions of the pen at that time. Of course, it is also possible to detect a change in the acceleration pattern when the peak value of acceleration has not reached the peak value, and change writing conditions such as writing pressure when the speed pattern when the pen is down has not reached the peak value.

【Effect of the invention】

As explained above, according to the present invention, the speed pattern when the pen is down is changed and set according to the change in acceleration when the pen contacts the recording surface when the pen is down, so the pen type, pen tip, etc. It is possible to set a high pen lowering speed in accordance with changes in the state of the pen, such as wear on the pen, changes in pen weight due to differences in the amount of ink remaining, the type of recording paper, etc., making it possible to draw at high speed. Furthermore, since the pen-down speed can be controlled in response to changes in the state of the pen and the recording medium, stable drawing quality can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the pen control device according to the present invention, FIG. 2 is a waveform diagram for explaining its operation, and FIGS. 3 and 4 are diagrams showing an example of the configuration of a part thereof. FIGS. 5 and 6 are flowcharts for explaining the operation of essential parts of the present invention. 2; Pen down/up setting signal generation section 3; Speed setting signal generation section 5: Correction pattern formation section 6; Speed pattern generation section 9, speed control section 10; Actuator 33: Acceleration sensor agent Patent attorney Masami Sato F ( AC) m Flowchart Figure 6

Claims (1)

[Scope of Claims] A drawing device including a pen driving means for holding a pen and bringing the pen tip into contact with and away from a recording surface, comprising: a moving acceleration of the pen tip when the pen tip contacts the recording surface; An acceleration detection means for detecting is provided, and a moving speed pattern when the pen tip is brought into contact with the recording surface from a state where it is separated from the recording surface is controlled based on the output of the acceleration detection means. A pen control device for a drawing device characterized by: