JPS61284497A - Pen vertical movement controller for automatic drawing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an automatic drawing machine, and more particularly to a pen vertical movement control device for vertically moving a pen with respect to a drawing surface.

[Background of the invention]

As described in Japanese Patent Application Laid-Open No. 58-86675, this type of conventional device memorizes the position immediately before lifting the pen and uses that position information as a base to lift the pen from the recording medium. The device lifts the pen a distance instructed by the processing device.

However, there is a method of lifting the pen a certain distance relative to the recording medium without having to memorize the position immediately before lifting the pen, and the above-mentioned publication does not mention anything about this point.

[Purpose of the invention]

An object of the present invention is to be able to lift a pen a certain distance from a recording medium without using a method of storing the position immediately before lifting the pen and controlling based on the position information.
High-speed response that prevents the pen from accidentally touching the recording medium due to the tilt of the recording medium when the pen moves in an elevated position. An object of the present invention is to provide a ben vertical movement control device for an automatic drafting machine.

[Summary of the invention]

The device of the present invention focuses on the fact that in an automatic drawing machine, the pen is lifted a certain distance from the recording medium by lifting it at a certain speed for a certain period of time. It was designed to be achieved.

[Embodiments of the invention]

Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a pen vertical movement control device for an automatic drawing machine according to the present invention. As shown in FIG. It is mechanically connected to 4.

By passing a current iA through the actuator 3, the actuator 3 moves in the vertical direction, and the current iA is controlled by the current input to the constant current amplifier 2.

The pen press heavy duty DA converter 1 also closes the internal analog switches E and F, so that each switch D,
A current proportional to the reciprocal of the weight resistances R4, R3 and R2 of E and F is passed through the constant current amplifier 2 to move the pen 5 to the recording medium 1.
Drives with constant pressure in 6 directions. Conversely, the converter l
By closing the analog switch C, the pen 5 is moved in the direction opposite to the recording medium 16 (
can be driven upward) with constant pressure.

As the pen 5 is driven up and down, the flag 4 also moves up and down, blocking the infrared rays from the infrared light emitting diode 7 by an amount proportional to the vertical position of the pen 5, thereby blocking the infrared rays reaching the infrared phototransistor 6. The amount is made proportional to the vertical direction of the pen 5, so that the position can be detected.

The position detection amplifier 9 has an internal variable resistor (not shown).
By appropriately adjusting the output (position output) P
is set to 10.2V when the pen 5 is located at the stroke upper limit 15 in FIG. 2, and +5.8V when the pen 5 is located at the stroke lower limit 17 in the same diagram. It has been adjusted.

The output P is a voltage linearly proportional to the position of the pen 5 from the upper limit 15 to the lower limit 17.

A spring 19 is provided to position the pen 5 at the upper limit 15 when the power is turned off. 11 is an inverting amplifier, and while the power is on, spring 1
In order to compensate for the pressure with which the pen 5 is pulled upwards by
(not shown) to the output of converter 1.

10 is a differential amplifier that differentiates the position output P in order to maintain a constant speed when the pen 5 moves with a constant pressure toward the recording medium 16 and to bring the pen 5 into contact with the recording medium 16 at a constant speed. , whose output (dimension represents the velocity of the pen 5) is coupled via an analog switch A with the output of the converter 1.

Reference numeral 14 denotes a phase compensation circuit, into which the position output P is inputted via a resistor R1a, and the output obtained by compensating the phase of the position output P is coupled to the output of the converter 1. Therefore, when the analog switches A, C, D, E, F, and H are OFF, the pen 5 moves with the phase of the phase compensation circuit 14 to the position where the position output P becomes Ov, that is, the position servo is activated. It will be configured. However, the internal circuit of the phase compensation circuit 14 is configured such that the position servo is disabled by closing the analog switch B.

12 is an inverting amplifier, the gain of which is l.

Therefore, the position output P and the output of the inverting amplifier 12 have opposite polarities and the same absolute value. 13 is a sample and hold circuit, which charges an internal capacitor with the output of the inverting amplifier 12 while the analog switch G is closed. The output of the sample and hold circuit 13 has the same level as the output of the inverting amplifier 12 with a certain phase lag. At the moment the analog switch G is opened, the sample and hold circuit 13 holds the output of the inverting amplifier 12 just before that until the analog switch G is closed next.

Note that the constant current drive circuit 8 is for keeping the current of the photodiode 7 constant. Further, the photodiode 7 and the phototransistor 6 are temperature-compensated, so that the influence on temperature is minimized.

Further, the analog switches A, B, C, D, E, F, G, and H can be opened and closed at appropriate times by a processing device (not shown). For example, when the output of the sample and hold circuit 13 is held at 13V, the analog switch H can be closed, and in this case, the phase compensation circuit 1
A signal obtained by adding the output of the sample and hold circuit 13 and the position output P through resistors Rla and Rlb having the same resistance value is input to the input of 4. Therefore, the position servo moves until the input of the phase compensation circuit 14 becomes O■, and as a result, the pen 5 becomes stable at a position where the position output P becomes 3V.

FIG. 3 shows an example of the mechanical structure of the pen driving section 18 in FIG. 1. In FIG. 3, a moving coil 3a, which is a movable part of the actuator 3, is formed by winding a conductor around a bobbin, and this moving coil 3a is connected to a fixture 3b.
It is possible to move up and down inside the magnet 3C which is fixed in place. That is, by passing a current through the moving coil 3a, the current of the moving coil 3a blocks the magnetic circuit 3d formed within the magnet 3c, and the supporting portion 3e
is driven, and as a result, the flag 4 and the pen 5 are connected to the recording medium 1.
It is configured to move up and down with respect to 6.

The operation of the above-mentioned circuit of the present invention will be explained below with reference to FIGS. 2 and 4.

As shown in FIG. 2, the recording medium 16 is located between the upper pen stroke limit 15 and the lower pen stroke limit 17. When the time axis t is taken to the right in the figure, the pen 5 moves up and down between the upper limit 15 and the lower limit 16 as shown in phases 1 to 1 in the figure. In this embodiment, the distance between the upper limit 15 and the lower limit 17 is set to 4.
On, the distance between the recording medium 16 and the upper limit 15 is about 2.7 states.

The operation modes of the pen 5 in the above phases ① to [phase] will be explained below. Note that the time in parentheses in each mode description is the operating time in that mode.

■... Pen standby mode... constitutes a position servo and is located approximately 0.13 m below the upper limit 15.

■...Pen-down acceleration mode...Mode to move while accelerating downward without speed control at the maximum pen pressure (in Figure 2, the accelerating state is omitted and shown as a straight line) ( 10msec).

(2) Pen-down constant speed mode: A mode in which the speed is controlled at a pen pressure of two-sevenths of the maximum pen pressure to contact the recording medium 16 at a constant speed (30 msec).

■...Drawing mode...The pen 5 is moved to the recording medium 16 using a pen pressure specified by a processing device (not shown) or an operator.
Mode in which you touch (you can draw by moving on the XY axes).

■,■...Silator lit mode...A certain distance (0,6
6fI) (10msec).

■...Same mode as ■ (15n+5ec).

■...Same mode as ■.

■...Long lift mode...Is it more of a waiting period than drawing mode■? &Mode to lift Heben 5 (1 (1msec)
.

[Phase]...Same mode as ■.

Each mode (1) to [phase] is controlled by analog switches A to H as shown in FIG. Here, the mode that expresses the feature of the present invention is the mode in which the mode changes from ① to ②. As shown in Figure 4, in mode ■, analog switches A and B are closed (1 in Figure 4 represents closed, 0 represents open), and the position servo is disabled and speed control is applied. The pen 5 is pressed against the recording medium 16 with the pen pressure set by closing (1). In mode ■, the pen pressure is changed from downward to upward while maintaining speed control, compared to mode ■. In other words, analog switches D, E,
Open F and close C. In addition, in mode (2), analog switch G is also closed to prepare for position measurement. As a result, in mode ■, the pen 5 rises at a constant speed, and in mode ■, when a predetermined period of time has elapsed after the start of mode ■, the analog switch G is opened and the current position Ps of the pen 5 is memorized. By opening analog switch B and closing analog switch H, pen 5 attempts to stabilize at position Ps. At this time, analog switch A is opened to stop speed control. In this way, the pen 5 can rise by 0.66 m with respect to the position of the recording medium 16 immediately before the pen rises, as shown in the dotted circle 20 in FIG.

Since the responsiveness of the vertical movement of the pen 5 of an automatic drawing machine has a great effect on the drawing time, it is important to minimize the lifting distance of the pen 5 from the recording medium 16 during drawing. In this case, the inclination and distortion of the recording medium 16 may cause a problem that the pen 5 comes into contact with the recording medium 16 when the pen is moved in an elevated state.

However, in the device of the present invention, the pen 5 can be placed at a constant distance from the recording medium 16 in the same way as the conventional device described above, so the responsiveness of the pen 5 can be increased without causing the above-mentioned problems. There is an effect.

Further, the allowable range of the recording medium 16 is from the stroke lower limit 17 to the start position 21 of mode (2), and if the recording medium 16 is within this range, the above-mentioned effect can be achieved.

〔Effect of the invention〕

As described above, according to the present invention, when the recording medium is within the pen down constant speed mode start position from the lower limit of the pen stroke, the pen can always be raised by a certain distance with respect to the recording medium, and The pen lift distance can now be minimized without being affected by tilt or distortion.
This has the effect of providing a pen vertical movement control device with high-speed responsiveness.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the device of the present invention, and FIG.
4 and 4 are diagrams for explaining the operation of the above device, respectively, and FIG. 3 is a sectional view showing an example of the main structure of the above device. DESCRIPTION OF SYMBOLS 1... DA converter for pen pressure running, 2... Constant current amplifier, 3... Actuator, 4... Pen vertical position detection flag, 5... Pen, 6... Infrared phototransistor , 7... Infrared light emitting diode, 8...
・Constant current drive circuit, 9...Position detection amplifier, 10.
... Differential amplifier, 11.12 ... Inverting amplifier, 13.
...sample hold circuit, 14...phase compensation circuit,
16... Recording medium, 18... Pen drive unit, 19...
·spring. Patent applicant Hitachi Seiko Co., Ltd. Agent Patent attorney Tadashi Akimoto Younger brother 1 [Figure 2 → Figure 3]

Claims (1)

[Claims] In an automatic drawing machine that creates a drawing on a recording medium by controlling the vertical movement of a pen in response to commands from a processing device, the vertical movement of the pen is controlled by a vertical position detector and an actuator that drives the pen. vertical position control means for moving the pen in a height; pressure control means coupled to the position control means for controlling pen pressure in the direction of the recording medium and vice versa; and vertical movement speed of the pen. speed control means coupled to said pressure control means for controlling said pressure control means; A pen vertical movement control device for an automatic drafting machine, comprising a pen lifting means coupled to a position control means and a speed control means.