JPH08258491A - Ink feed pressure control device for x-y plotter - Google Patents

Abstract

PURPOSE: To better precision in pressure control so as to improve plotting quality in an X-Y plotter equipped with an ink feed pressure control device. CONSTITUTION: In a data table of a pressure signal generating section 7 arranged at a plotting control section 3 of an X-Y plotter, a plurality of pressure control signal data corresponding to maximum speed and acceleration of a pen head are store. A CPU 5 designates a data address of a pressure pattern generating section 7 based on information such as setting of plotting speed and setting of type of pen in a plotting data. During execution of plotting, the pressure pattern generating section 7 outputs a designated pressure control signal to a solenoid valve driving circuit 20, and an X-axis motor 21, a Y-axis motor 22, a Z-axis actuator 23 and an electromagnetic proportional control valve 8 of an ink feed pressure control device are operated simultaneously. The pressure of an ink tank of an ink pen is controlled by a pattern similar to a pattern of acceleration, constant-speed movement, and deceleration of the pen head, so that the thickness and density of a drawn segment become uniform from the starting point to the terminal point.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an XY plotter, and more particularly to an ink supply pressure control device for an ink pen in an XY plotter.

[0002]

2. Description of the Related Art Conventionally, as the drawing speed of an XY plotter has been increased, an ink supply pressure control device for pressurizing the air pressure in the ink tank of an ink pen to make the ink supply amount to the pen tip follow the drawing speed of the pen head. The XY plotter provided is known.

Further, there has been proposed a device in which the air pressure can be switched between a positive pressure and a negative pressure so that the air pressure in the ink tank is reduced when the pen head is raised to prevent ink dripping. In this type of ink supply pressure control device, the discharge port and the suction port of the blower are connected to the ink tank by pipelines, and pressure control means such as a switching valve and a pressure control valve are provided in each pipeline. is there. Then, the moving speed of the pen head is detected at the time of drawing and is fed back to the pressure control means, and when the pen head moves to the screen, the valve on the suction port side is controlled in the closing direction to control the air pressure in the ink tank. Is controlled according to the moving speed. Further, when the pen head is rising from the screen, the air pressure in the ink tank is switched to a negative pressure by controlling the valve on the ejection port side in the closing direction.

[0004]

A conventional ink supply pressure control device for an XY plotter detects the moving speed of a pen head during image formation and feedback-controls the pressure control means, so that the pneumatic pressure increases as the image formation speed increases. There is a drawback that the control delay increases. Particularly, there is a problem in the control accuracy in the vicinity of the start point and the end point of the line segment, that is, in the acceleration period and the deceleration period. Therefore, regardless of the printing speed, there will be technical problems to be solved in order to perform more accurate pressure control and improve the printing quality.
The present invention aims to solve the above problems.

[0005]

SUMMARY OF THE INVENTION The present invention is proposed to achieve the above-mentioned object, and an ink tank of an ink pen and an air pressure generator are connected by a pipe line, and a pressure controller is connected to the pipe line. In the ink supply pressure control device of the XY plotter that controls the pressure controller to raise and lower the internal pressure of the ink tank, the image forming control unit of the XY plotter,
A means for generating pressure control data by judging the acceleration, maximum speed, and pen type of the pen head based on information such as the setting drawing speed and pen type setting in the drawing data, and the pen head drive based on the drawing data and pressure control data. An ink supply pressure control device for an XY plotter, which is provided with a function of controlling the internal pressure of the ink tank according to the image forming speed of the pen head, by a control unit that synchronously drives the printer section and the pressure controller. It is a thing.

[0006]

In the ink supply pressure control device according to the present invention, the pressure control data generating means provided in the image forming control section of the XY plotter includes:
The pressure control data is generated by determining the acceleration of the pen head, the maximum speed, and the pen type based on information such as the set drawing speed and the pen type setting in the drawing data.

The drive control means of the image formation control section synchronously drives the pen head drive section and the pressure controller of the ink supply pressure control device based on the image formation data and the pressure control data, and the ink tank of the ink tank is driven according to the image formation speed of the pen head. Control the internal pressure.

At the time of drawing, the internal pressure of the ink tank is controlled by a pattern similar to the acceleration, constant speed movement, and deceleration patterns of the pen head, and the thickness and density of the drawn line segment are uniform from the start point to the end point. Further, since the maximum pressure level and the negative pressure level are selected according to the pen type setting data of the ink pen, there is no difference in drawing quality depending on the pen type.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram of an XY plotter including an ink supply pressure control device. The drawing data output from the host computer 1 is input to the buffer memory 4 of the drawing control unit 3 via the interface 2. The inputted drawing data is expanded by the CPU 5 in XYZ according to the format setting data in the drawing data and stored in the memory 6.

In addition, as shown in FIG. 2, the pressure signal generator 7 of the drawing controller 3 previously has a maximum pen head speed (Vi) and an acceleration (Gi, -G) which differ depending on the format setting.
i) and a plurality of solenoid valve control signal output pattern data for controlling the opening / closing acceleration and opening area of the solenoid proportional control valve 8 of the ink supply pressure control device in order to control the ink supply pressure corresponding to the pen type. It is stored as a table.

The CPU 5 adds addressing data for designating the control signal output pattern data of the pressure signal generator 7 to the XYZ vector data based on the information such as the drawing speed setting and the pen type setting in the drawing data and stores it in the memory. Store in 6.

The pneumatic circuit of the ink supply pressure controller is
As shown in FIG. 3, a blower or other blower 9 is connected to a discharge port 10 and an electromagnetic proportional control valve 8 by a pipe line 11,
The ink pen 1 is attached to the air pressure outlet 12 provided in the conduit 11.
The third ink tank 13a is connected via the flexible tube 14. By controlling the opening area of the electromagnetic proportional control valve 8, the internal pressure of the conduit 11 and the ink tank 13a can be continuously changed from atmospheric pressure to the discharge pressure of the blower 9.

In addition to the pneumatic circuit shown in FIG. 3, the pneumatic circuit shown in FIG. 4 is provided with a 4-port directional control valve 16 for switching the pipe line 11 between the discharge port 10 and the suction port 15 of the blower 9. By operating the 4-port directional control valve 16, the internal pressure of the ink tank 13a can be switched between positive pressure and negative pressure, and the pressure can be controlled by the electromagnetic proportional control valve 8 in any state.

Further, in the pneumatic circuits shown in FIGS. 3 and 4, the internal pressure is also changed by changing the drive current of the blower 9 by forming a vent hole at the end of the conduit 11 instead of the electromagnetic proportional control valve 8. It can be changed continuously.

At the time of executing the drawing, the drawing control unit 3 shown in FIG.
Read the XYZ vector data from the memory 6
Axis drive circuit 17, Y-axis drive circuit 18, Z-axis drive circuit 19
The control signal is output to the pressurizing signal generator 7, and the addressing data of the control signal output pattern is output to the pressurizing signal generator 7. The pressurizing signal generator 7 outputs the control signal corresponding to the control signal output pattern data of the specified address. Output to the solenoid valve drive circuit 20. As a result, the X-axis motor 21 and the Y-axis motor 2
2. The Z-axis actuator 23 and the electromagnetic proportional control valve 8 are synchronously driven to execute the image formation while controlling the ink supply pressure.

In order to eliminate the delay in the response of the pneumatic circuit to the line pressure, the print control unit 3 controls the solenoid valve drive circuit 20 with respect to the output timing of the drive signal to the Z-axis drive circuit 19.
The output timing of the drive signal of the
It is set so that the air pressure in the ink tank reaches an appropriate value when the ink pen touches the screen or takes off.

At the time of drawing, the internal pressure of the ink tank 13a is controlled by a pattern similar to the acceleration, constant speed movement, and deceleration patterns of the pen head, and the thickness and density of the drawn line segment are uniform from the start point to the end point. . Also, although the optimum air pressure varies depending on the thickness of the pen tip of the ink pen, etc., the control signal output pattern is selected according to the pen type setting data in the drawing data, so the difference in drawing quality depending on the pen type is also possible. Will be resolved.

Further, by using the pneumatic circuit shown in FIG. 4 and controlling the negative pressure in the ink tank when the pen head is raised, the ink drop from the pen tip and the line width expansion phenomenon at the start point of the line are prevented. it can.

The present invention is not limited to the above-described embodiment, but the construction of the drawing control unit 3 can be variously modified within the technical scope of the invention, and the invention is modified by them. It goes without saying that it extends to all things.

[0020]

As described in detail in the above embodiment, the present invention controls the ink supply pressure of the ink pen in accordance with the acceleration and maximum speed of the pen head of the XY plotter and the conditions such as the pen type. A uniform drawing quality can be obtained from the start point to the end point of the line segment regardless of the type of pen or pen. Further, since the control data of the ink supply pressure is acquired before the start of image formation, it is possible to contribute to the improvement of image formation quality without causing a control delay.

[Brief description of drawings]

FIG. 1 is a block diagram of an XY plotter showing an embodiment of the present invention.

FIG. 2 is an explanatory graph showing a solenoid valve control signal output pattern of a pressurization signal generator.

FIG. 3 is a pneumatic circuit diagram of the ink supply pressure control device.

FIG. 4 is a pneumatic circuit diagram showing another embodiment of the ink supply pressure control device.

[Explanation of symbols]

 3 Drawing control unit 5 CPU 6 Memory 7 Pressurization signal generation unit 8 Electromagnetic proportional control valve 9 Blower 11 Pipe line 12 Air pressure outlet 13 Ink pen 13a Ink tank 16 4-port directional control valve 20 Solenoid valve drive circuit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Shoji Kishi, 6-6 Hakozakicho, Nihonbashi, Chuo-ku, Tokyo, Max Co., Ltd.

Claims (1)

[Claims] 1. An ink tank of an ink pen and an air pressure generator are connected by a pipeline, and a pressure controller is provided in the pipeline.
In an ink supply pressure control device for an XY plotter that controls the pressure controller to raise or lower the internal pressure of the ink tank, an image forming control section of the XY plotter provides information such as setting speed and pen type setting in the drawing data. And means for generating pressure control data by determining the acceleration, maximum speed and pen type of the pen head, and control means for synchronously driving the pen head drive unit and the pressure controller based on the drawing data and the pressure control data. The ink supply pressure control device for the XY plotter is provided with a function of controlling the internal pressure of the ink tank according to the drawing speed of the pen head.