JPH0371871A - Shuttle turnback control device of printer - Google Patents

Abstract

PURPOSE:To enable completion of a turnback process in a short time and with saved energy even in the case of a high-speed shuttle drive by reducing the speed of a shuttle from a target value in a constant speed control area to a level on which the speed can be adequately controlled before a time when the speed is changed from a constant control area to a reflection control area. CONSTITUTION:In a shuttle-type print in which a shuttle with a printing head prints printing paper in its shuttle motion, the speed of the shuttle is reduced to a level Tphi where it can be adequately controlled from a target value Tc in the constant control area before (I=n) a time when the speed is changed from the constant control area to the turnback control area. Therefore, a invert ed magnetic field is applied to the drive motor of the shuttle starting with a speed T at a turnback starting point of time A. Thus the time required for the speed to be reduced to 0 becomes short. Consequently, the speed of the shuttle can reach the target value Tphi at a point of time B when the printing of a next line starts.

Description

[Detailed Description of the Invention] [Summary] This invention relates to a shuttle reversal control device for a shuttle-type printer in which a shuttle equipped with a print head prints while reciprocating over printing paper, and the shuttle reversal control device can be used in a shuttle-type printer that prints while reciprocating on printing paper, even when the shuttle is being driven at high speed. The purpose is to complete the reversal in a timely and energy-saving manner, and before the transition from the constant speed control area to the reversal control area, the shuttle speed is increased from the target value in the constant speed control area to a speed that can be sufficiently controlled. A shuttle reversal control device for a printer is characterized in that a reversal operation is started after deceleration.

[Industrial application field]

The present invention relates to a shuttle type wire dot printer, and more particularly to a shuttle reversal control device for this type of printer.

In shuttle-type wire dot printers, a shuttle equipped with multiple print heads performs printing while reciprocating horizontally on the printing paper, and when a predetermined line of printing is completed, the shuttle moves in one direction. The printing paper is fed while reversing from one direction to the other direction. It is necessary to smoothly control the speed change of the shuttle during such a reversal to shorten the time required for the reversal and reduce power consumption.

[Conventional technology]

In conventional shuttle-type wire dot printers, the shuttle reversal control is normally carried out when the reversal excitation is started after printing of a predetermined line is completed, and the speed of the shuttle is once zero and then accelerated again to reach a constant speed that is the target value of the control. In this case, since the paper is fed during the time required for reversal, if the reversal time is too short, the next printing will start before paper feeding is completed, resulting in irregular printing. Conversely, if the time required for reversal is too long, the printing speed will slow down.

For this reason, control is performed to keep the reversal time constant, but in printers with several speed modes,
In high-speed mode, the speed at the start of reversal is quite high, making it difficult to complete reversal control within a predetermined time.
If the shuttle operation is repeated for a long time, the temperature of the motor coil increases and the reversal time becomes longer. As a countermeasure, increasing the motor torque can be considered.
This poses a problem in that it leads to increased costs and increased power consumption.

[Problem to be solved by the invention]

As described above, in the conventional shuttle reversal control, especially when printing is performed by moving the shuttle back and forth at high speed, the reversal control takes time, leading to an increase in the temperature of the motor coil and power consumption.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a shuttle reversal control device that can complete reversal in a short time and with energy savings even when the shuttle is being driven at high speed.

[Means to solve the problem]

In order to solve such problems, according to the present invention, in a shuttle-type printer in which a shuttle equipped with a print head performs printing while reciprocating on printing paper, as shown in FIG. Before the time (^) when transitioning from the area to the inversion control area (1=n), the speed (Tφ) that can sufficiently control the shuttle speed from the target value (Tc) in the constant speed control area is determined.
A shuttle reversal control device for a printer is provided, characterized in that the shuttle reversal control device for a printer starts a reversing operation after decelerating to a maximum speed.

[Function] According to the present invention, before the reversal start time (^) (1=n)
Since the speed of the shuttle is decelerated to a speed (Tφ) that can be sufficiently controlled, at the start of reversal (A), a reversal magnetic field is applied from the speed Tφ to the shuttle drive motor (not shown), so that the speed increases. The time it takes to reach zero becomes shorter.

Therefore, as shown in FIG. 1, the speed of the shuttle can reach the target value (Tc) at the printing start time point (B) of the next line.

In addition, if the shuttle drive motor coil (not shown) becomes hot and the drive motor torque decreases,
The deceleration and acceleration of the shuttle decrease, and as shown in Figure 2, the inclination angle decreases by Δθ, but the time point at which the speed reaches zero in the reversal region is set to be in the middle of the reversal region or before it. If this is done, the speed of the shuttle can reach a value close to the target value (Tc) at which printing can be started at the printing start time point (B) of the next line. Note that the speed that can be sufficiently controlled (Tφ) means the speed at which complete reversal can be performed within a predetermined reversal time, that is, the speed of the shuttle is once reduced to zero within the predetermined reversal time after the start of reversal, and printing is resumed. This is the initial speed that can be brought up to a starting speed,
For printers that can print in two or three speed modes such as high speed mode and medium speed/low speed mode, if the high speed mode is the target value (Tc), Tφ can be set to the speed of the medium speed or low speed mode. . Also, the time when the shuttle starts decelerating (1
-n) is set so that the shuttle speed reaches a sufficiently controllable speed (Tφ) before the reversal start point (A) (x). That is, the torque reduction due to the high temperature of the drive motor coil is saturated. In some cases, it is preferable to set the value to x-0.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 3 is a block diagram of a shuttle reversal control device that can be used in the present invention, and includes a microprocessor unit (?jPtl), a program ROM (ROM), a work ram (RAM), a timer, an input port, and an output port. It consists of a control circuit, a shuttle drive motor, a motor control circuit for driving the motor, and a sensor for detecting movement of the shuttle.

FIG. 4 is a perspective view showing the shuttle portion of the shuttle-type wire dot line printer. By reciprocating on the shaft 12 with a predetermined stroke slightly shorter than the above-mentioned interval, printing is performed in the horizontal direction on the printing paper 4 on the platen 13. 15 is a linear drive motor that drives the shuttle back and forth, and 16 is a sensor that detects the speed of the shuttle 10 and outputs a signal with a period corresponding to the speed of the shuttle.

Fig. 5 is the main routine of the shuttle control flow according to the present invention, Fig. 6 is the subroutine of the reversal control part indicated by * in Fig. 5, Fig. 7 is a diagram showing each signal during constant velocity control, and Fig. 8 is a diagram showing each signal during constant velocity control.
Figures (a) and (b) are diagrams showing deceleration and reversal control before reversal. First, in the initial setting, the speed (T) is set to the target speed (Tc). This speed (Tc) is a speed in a constant speed control range corresponding to a target printing speed, for example, when printing is performed in high speed mode. Prior to starting printing, the drive motor is accelerated and excited. As mentioned above, the sensor constantly outputs a signal with a period corresponding to the speed of the shuttle.
Measure the cycle with a timer.

In the constant speed control region after printing starts, as shown in FIG. 7, acceleration/deceleration control is performed so that the speed (T) of the shuttle becomes the target speed (Te). That is, accelerated excitation is performed when T < Tc (for example, T - Td). Conversely, when T>Tc (for example, T=Tf), deceleration excitation is performed, and this operation is repeated.

Reversal control is performed by a signal indicating the end of printing, and in the present invention, as shown by the broken line area in FIG. is decelerated to a speed (Tφ) that can be sufficiently controlled. That is, for I=n, the timer is set to I=O at the time of starting printing in advance, and as shown in FIG. 8(a),
When the timer reaches I=n, the drive motor is decelerated and excited to reduce the speed of the shuttle from the target speed (Tc) to Tφ.

From the point at which printing ends, normal reversal control begins.

That is, as shown in FIG. 8(b), the drive motor is reversely excited by the print end signal. Eventually, the shuttle's speed reaches zero and reverses. Reverse excitation means that the shuttle moves at a certain speed (for example, a certain period T = T as shown in Figure 6).
Continue until you reach A). The period (TA) in this case is
This is the speed at which constant velocity control as shown in FIG. 7 can be started. After this, constant speed control is performed toward the target speed (Tc) until the timer reaches I=n.

[Effects of the Invention] According to the present invention as described above, the speed of the shuttle is reduced to a speed that can be sufficiently controlled before the transition from the constant speed control area to the reversal control area, so that the reversal control In the region, the time required for the shuttle speed to reach zero can be shortened, and the shuttle speed can reach the target value or a value close to this when printing the next line starts. Therefore, even when reversing in high-speed mode, the time required for reversing does not increase.This allows high-speed printing without increasing the motor torque, reducing power consumption and other costs. can be achieved.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the shuttle speed in shuttle reversal control (when the coil is at room temperature) of the printer according to the present invention, Fig. 2 is a diagram showing the shuttle speed when the coil is at high temperature, and Fig. 3 is a diagram showing the shuttle reversal control used in the present invention. Block diagram of the device,
FIG. 4 is a perspective view showing the shuttle portion of the shuttle-type wire dot line printer, FIG. 5 is the main routine of the shuttle control flow according to the present invention, and FIG. 6 is the subroutine of the reversal control portion indicated by * in FIG. FIG. 7 is a diagram showing each signal during constant velocity control, and FIGS. 8(a) and (b) are diagrams showing deceleration and reversal control before reversal. IO...Shuttle, 11...Print head, 1
2... Axis, 13... Platen, 14... Print paper, 15... Drive motor, 16... Sensor.

Claims (1)

[Claims] 1. In a shuttle type printer in which a shuttle (10) equipped with a print head (11) prints while reciprocating over the printing paper (14), from the point (A) when the constant speed control area shifts to the reversal control area The reversing operation is started after the speed of the shuttle is attenuated to a speed (Tφ) that can be sufficiently controlled from the target value (Tc) in the constant speed control region before (I=n). Printer shuttle reversal control device.