JPS5822359B2 - Pen vertical drive control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for driving and controlling the vertical movement of a drawing pen head of an automatic drawing machine.

As shown in FIG. 1, a conventional device for controlling the vertical drive of a pen head includes a constant current source 1, an excitation coil 2, a movable iron sleeve 3, a drawing pen 4, a control gate 5, and a control gate 6. It is composed of a transistor switch 7 and a spring 7, and its operation is such that when a pen lowering signal is input, the transistor switch 6 is turned on by the control gate 5, current flows through the coil 2, overcomes the force of the spring 7, and closes the sleeve 3. moves downward.

This brings the drawing pen 4 into contact with the drawing surface.

Furthermore, when the pen-up signal is input, the transistor switch 6 is turned off, and no current flows through the coil 2.
The sleeve 3 is moved upward by the force of the spring 7.

In the conventional device, the pen is moved up and down by the above-described operation, but since this device has a movable iron core, it has the following drawbacks.

1) When the excitation current is turned on, no downward torque is generated until the iron core is magnetized, resulting in a delay in operation.

2) The more the generated torque goes to the lower end, the stronger it becomes, and the jumping of the pen tip becomes more likely to occur.

3) When the excitation current is turned off, the residual magnetization of the iron core acts, causing a delay in operation.

Therefore, in order to realize a pen head with faster response, it was necessary to solve this drawback.

Also, Utility Model Publication No. 52-46184 or Special Publication No. 53-34
No. 532, in order to drive the pen faster, the vertical movement of the pen is controlled by detecting a signal corresponding to the amount of movement, speed, or acceleration of the pen and feeding it back to the pen drive system. There is.

However, since the detection device that detects the amount of movement of the pen is attached to the periphery of the pen, that is, to a fixed part such as an outer frame (not shown) (collectively referred to as the writing device), the load on the writing device increases. When drawing by moving parallel to the drawing board, inertia caused bulges due to overshoot at the corners of the drawing, and the start and stop were not smooth, which prevented speeding up. .

Furthermore, since the pen position is detected and feedback control is performed, there is a time delay caused by the control device, making it difficult to increase the speed, especially in automatic drafting machines that use servo devices that drive at high speed.

The purpose of the present invention is to eliminate the above-mentioned drawbacks of the prior art, and to improve the drawing efficiency of an automatic drafting machine and shorten the drawing time by making the pen move up and down quickly and smoothly. The aim is to provide the opportunity.

The configuration of the present invention is to receive command signals for vertical movement of the pen and output command signals for accelerating when raising and lowering the pen, subsequently decelerating the pen, and applying pen pressure during drawing for each set time. and a coil current control circuit that receives each command signal from this timing circuit and supplies acceleration current and deceleration current when raising and lowering the pen to the pen vertical drive coil, and current for pen pressure when drawing. (hereinafter collectively referred to as a drive circuit section).

Ru.

Note that the above-mentioned pen vertical drive coil may be of a moving coil type that does not have a delay due to the magnetization of the iron core, etc.Also, even with the conventionally used moving coil type, the deceleration current does not interfere with the magnetization of the moving iron core. Since it acts as a current for 74 magnetization, it can be similarly adopted.

FIG. 2 shows an example in which the present invention is used to control a moving coil type pen head.

10 is a timing circuit section, and 11 is a drive circuit section for causing a drive current to flow to the moving coil 12 in response to command signals B, C, and D from the timing circuit section.

Further, 13 represents a constant current source, 14 represents an amplifier, and 15 represents a switch.

The operation of this embodiment will be explained according to the operation of each part shown in FIG.

In FIG. 3, A, B, C, and D are the command signals A,
The on/off states of B, C, and D are shown, io shows the current flowing through the moving coil 12, and E shows the moving state of the pen tip.

In response to the pen lowering command signal A, the timing circuit 10 turns on the command signal B for a time T1 to flow the acceleration/acceleration current ■1 when lowering the pen, as shown in FIG.
Turn on for 2 hours and reduce the current ■.

flow. By optimally setting each current I1, T1, and I2, the pen tip moves smoothly to the drawing surface and stops as shown in FIG.

At this time, by turning on the command signal and applying pen pressure current ■2, you can create a drawing without applying shock to the drawing surface.
Further, the pen tip can be lowered without jumping or the like.

Also, for the raising operation, the raising command signal C is turned on for T3 hours, and the current ■.

After this, command signal B is ONL for a time T4, and current 1 is applied to increase the upward movement of the pen tip so that it smoothly contacts the dead stop at the upper end of the pen head.

That is, in the drive circuit section 11, the timing circuit section 1
0 itch predetermined time T1. I2 and T3. The switch 15 that excites the moving coil 12 with a predetermined excitation current (Io, 11.I2) is driven only during T4.

This excitation time T1. I2. (or T3.T4) and excitation current (acceleration current ■).

, deceleration current■1. The pen pressure current I2) is determined by various conditions such as the weight of the pen and the speed at which the pen is moved up and down, but it should be adjusted depending on the variation in pen weight due to manufacturing and the smoothness of the friction of the pen up and down mechanism. is practical.

By performing this adjustment, the state of movement E of the pen tip can be controlled without impact.

As described above, since the present invention does not require a position detection device, the writing device is light and its inertia can be reduced. No bulges due to overshoot occur in drawing, and furthermore, starting and stopping are easy, and drawing time can be shortened.

Further, since feedback control of the pen position is not performed, there is no delay time caused by the control device, and drawing can be performed at high speed.

In addition, it was possible to increase the speed of the vertical movement of the pen head, and moreover, it was possible to make the impact on the drawing surface less than that of the conventional pen head.

This also eliminated the problem of jumping, which was a hindrance to high-speed drawing, and improved drawing quality.

Further, by applying the present invention to a conventional movable iron core type pen head, response delay can be reduced due to the magnetization effect of the iron core.

As a result, by using the control method according to the present invention even in the conventional movable iron core type pen head, the response characteristics are significantly improved compared to the conventional method.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating a pen vertical drive control device according to the prior art, FIG. 2 is a system diagram of an embodiment of a pen vertical one drive control device according to the present invention, and FIG. It is a waveform diagram of each part explaining operation. DESCRIPTION OF SYMBOLS 10... Timing circuit section, 11... Drive circuit section, 12... French pin coil, A... Vertical command signal B... Acceleration command signal, C... Deceleration command signal, D...
- Pen pressure command signal.

Claims (1)

[Claims] 1. In a pen vertical drive device used in an automatic drafting machine, a drive circuit unit supplies a pen vertical drive coil with acceleration current and deceleration current when raising or lowering the pen, and current for pen pressure during drawing; A vertical drive control device comprising a timing circuit that outputs a command signal for driving the pen in a predetermined order and timing to the drive circuit.