JPH11170652A - Printing device shuttle control method - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve the speed stability of a constant speed movement section of a hammerbank in a linear motor shuttle mechanism provided with a biasing means at the time of hammerbank reversal, and to easily improve printing quality and printing speed. The task is to make it work. SOLUTION: In a section where the urging force from the reversing urging means is acting from the end of acceleration during the reciprocating movement of the hammer bank to near the start of constant velocity, a suppression current for generating thrust in a direction opposite to the urging force is applied to the coil. In the section where the repulsive force from the reversing urging means is applied near the start of deceleration from the end of constant velocity during the reciprocating movement of the hammer bank and near the start of deceleration, a speed increasing current that generates thrust in the direction opposite to the repulsive force is applied to the coil. This can be achieved by energizing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus having a linear motor type shuttle mechanism, and more particularly, to a shuttle mechanism section of a linear motor having reversing biasing means for biasing reversal movement. And the reciprocating movement control of the.

[0002]

2. Description of the Related Art In a printing apparatus which has a shuttle mechanism of a linear motor system and which reciprocates a hammer bank provided with a plurality of printing elements (dot printing hammers, etc.) using the shuttle mechanism, in order to improve printing speed, A shuttle mechanism provided with reversing biasing means utilizing repulsion force of a spring or the like when the hammerbank is reversed has been developed.

FIG. 4 shows a configuration of a linear motor shuttle mechanism which is an example of the prior art.

A hammer bank 10 having a plurality of dot printing hammers is supported by a linear motion bearing 12 and reciprocates on a guide shaft 11. The linear motor unit 20, which is a power source for reciprocating operation, includes at least a coil 21 and a magnet 24 as components.
2 and a constant velocity coil 23. The hammerbank 10 and the coil 21 are connected to at least one timing belt 31 and have at least one pair of supported timing pulleys 3.
The shuttle mechanism can be operated by the power from the linear motor unit 20 by the reversing mechanism unit 30 composed of two.

Further, the hammerbank 10 and the coil 21
Inverting urging means (for example, a spring) 40 is disposed at a position for urging the inversion at both end portions. The reversing biasing means is not limited to the spring 40, but may be a means using the same polarity repulsion of a magnet.

The reciprocating reciprocating motion of the hammerbank 10 and the coil 21 is performed by calculating the position and reciprocating speed of the hammerbank 10 by a position detecting sensor 50 attached to a movable part, and calculating the reciprocating speed curve on a predetermined reciprocating motion. Works. The drive is controlled by a shuttle control circuit 60 that changes the value of a current supplied to the coil 21 and a shuttle drive circuit 70 that supplies a current to the coil 21.

FIG. 5 shows the speed waveform and coil drive current of the linear motor shuttle mechanism. However, the speed waveform in FIG. 5 represents an ideal control curve, which is slightly different from the speed waveform at the time of actual reciprocating movement in the prior art.

[0008] The shuttle operation of the hammerbank is divided into a reversal section and a constant velocity section as shown in a velocity waveform. In the reverse section, the deceleration coil 22 is energized to perform deceleration control and acceleration control, and in the constant velocity section, the constant velocity coil 23 is energized to perform constant speed control of constant speed movement. Since the reversing section requires a larger thrust than the constant velocity section, for example, by disposing more reversing coils 22 than the constant velocity coil 23 as shown in FIG. Also, the thrust generated by the reversing coil 22 is increased.

On the other hand, in order to meet various printing needs,
Printing devices with several printing speed patterns have been developed. In such a printing apparatus, in the shuttle mechanism provided with the reversing urging means, in order to simplify the structure, the distance of the urging section is constant regardless of the printing speed setting. That is, for example, in the case of a printing apparatus having three types of printing speeds, that is, a normal printing speed, a high printing speed, and a low printing speed, all the urging sections to the reversing urging means in the reversing section are most likely to be accelerated / decelerated. It is set to the reversal section at the time of high-speed printing speed setting that requires a large force. Therefore, as shown in FIG. 6, when a low printing speed is set, the energizing section extends to the constant speed section. The left reversing bias section is referred to as position X1 to left reversing position XL to position X1, and the right reversing bias section is referred to as position X2 to right reversing position XR to position X2.

[0010]

FIG. 7 shows a speed waveform and a coil drive current when the energizing section overlaps with the constant velocity section.

As is apparent from the drawing, in the conventional shuttle control method, in the constant velocity section, only the constant velocity coil is energized in a certain direction according to the movement direction of the hammerbank. Therefore, in the section where the biasing force by the reversing biasing means in the first half of the constant velocity section is acting, electricity is supplied so that the excess biasing force acts on the movement direction of the hammerbank. It is not possible to cancel, and even if the energizing current is set to zero, it becomes higher than a predetermined speed.

In the section in which the repulsion by the reversing urging means in the latter half of the constant velocity control is applied, electricity is supplied so that the repulsive force of the reversing urging means acts in a direction to cancel the repulsion. With the speed coil alone, a thrust sufficient to cancel the repulsive force cannot be obtained, and the speed becomes lower than a predetermined speed.

As described above, in the conventional shuttle control, since the speed stability of the hammerbank in the constant speed section is significantly reduced, there is a problem that the print quality is deteriorated.

Further, since the repulsive force and the urging force of the reversing urging means are used, the speed reduction of the hammerbank due to the repulsive force and the excessive speed due to the urging force are anticipated in advance, and the maximum speed of the constant velocity section of the hammerbank is considered. The speed must be lower than a predetermined speed determined by the limitations of the hammer printing ability and the print data processing time. Therefore, in the conventional shuttle control system, the speed in the constant speed section is significantly reduced, and the control is performed such that the maximum speed is within the predetermined speed. Therefore, there is a problem that the printing speed is significantly reduced as compared with the operation at the predetermined speed. Was.

Accordingly, it is an object of the present invention to provide a shuttle mechanism provided with a reversing biasing mechanism, in which the speed stability in a constant speed section is improved, and the printing quality and the printing speed are improved.

[0016]

According to a first aspect of the present invention, there is provided a hammerbank having a plurality of printing elements mounted thereon, at least a magnet and a coil, and a drive current supplied to the coil. A linear motor type shuttle mechanism having reversing urging means for energizing the hammerbank to reciprocate the hammerbank and energizing reversal of the reciprocation of the hammerbank near both ends of the amplitude of the reciprocating motion of the hammerbank. In the printing device having, during the reciprocating movement of the hammer bank and the biasing force from the reverse biasing means,
Alternatively, a driving current such that a thrust in a direction opposite to the urging force or the repulsive force is generated in the section where the repulsive force is acting is applied to the coil.

According to a second aspect of the present invention for solving the above-mentioned problems, a hammerbank having a plurality of printing elements is provided.
At least a magnet and a coil are provided, and the hammer bank is reciprocated by applying a drive current to the coil, and the reciprocation of the reciprocation of the hammer bank is provided near both ends of the amplitude of the reciprocation of the hammer bank. A printing apparatus having a linear motor type shuttle mechanism provided with a reversing biasing means for biasing, wherein the printing apparatus comprises a plurality of types of reciprocating speed patterns of the hammer bank in accordance with a printing mode. The drive timing of the drive current to the coil and the magnitude of the drive current are preset for each speed pattern, and the hammer bank is reciprocating and the biasing force or the repulsive force from the reversing biasing means is applied. In a section where the coil is driven, a drive current such that a thrust is generated in a direction opposite to the urging force or the repulsion force is applied to the coil. In the door.

Preferably, in order to generate a thrust contrary to the urging force from the reversing urging means, a suppression current is supplied near the start of constant speed from the end of acceleration during reciprocation of the hammer bank, and In order to generate a thrust contrary to the repulsive force from the means, it is preferable to apply a speed-up current from the end of constant speed during the reciprocating motion of the hammerbank to the vicinity of the start of deceleration.

It is preferable that the suppression current is decreased as the urging force from the reversing urging means decreases, and the speed-up current is increased as the repulsive force from the reversing urging means increases.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings.

The structure of the shuttle mechanism is the same as that of the prior art, and will not be described.

FIG. 1 shows a speed waveform and a coil drive current of the shuttle mechanism, and FIG. 2 shows a drive circuit of the inversion coil.

In order to solve the above-mentioned problem, in the present invention, as shown in FIG. 2, a drive current which generates a thrust in a direction opposite to the biasing force from the reverse biasing means or the repulsive force can be applied to the reverse coil. As shown in the coil drive current waveform of FIG. 1, of the sections in which the urging force from the reversing urging means or the repulsive force is acting on the hammerbank, the first half, the second half, In the latter half of the acceleration section, the urging force from the reversing urging means and a current that generates a thrust in a direction opposite to the repulsive force are applied to the reversing coil, thereby increasing the speed stability in the constant velocity section and printing. Improves quality and printing speed.

Hereinafter, description will be made with reference to FIG.

The left urging section by the reversing urging means is located at the position X.
1 to the left inversion position XL to the position X1, and the right energizing section is the position X2 to the right inversion position XR to the position X2. In the biasing section, a repulsive force acts on the decelerating section side and a biasing force acts on the accelerating section side with the inversion position (intersection with the horizontal axis of the graph) as a boundary. Therefore, in the present invention, in order to enhance the speed stability in the constant velocity section, in the sections (V1 to X1, -V1 to X2) in which the urging forces of the second half of the acceleration section and the first half of the constant velocity section act, Is supplied with a suppression current. As a result, the urging force applied to the hammerbank can be canceled, and it is possible to prevent an excessive speed in the first half of the constant velocity section. On the other hand, the section (X2
To X3, X1 to X0), a speed-up current is applied to the inversion coil. This makes it possible to cancel the repulsive force applied to the hammerbank, and to prevent a reduction in speed in the latter half of the constant velocity section.

The control will be described in detail with reference to the flowchart of FIG. The symbols used in FIG.
Inside.

After the start of the hammerbank, an acceleration current is supplied to the inversion coil to control the acceleration of the hammerbank. When the speed of the hammerbank is accelerated to V1, a suppression current is supplied to the inversion coil in a direction opposite to the acceleration current, and a thrust is generated in a direction to cancel the urging force applied to the hammerbank. The speed V1 is a value determined for each print speed setting. The suppression current is supplied to a position X1 at which the biasing force from the reverse biasing means does not act. At this time, the suppression current decreases as the urging force from the reversing urging means decreases. The profile of the suppression current is determined for each print speed setting.

Next, a constant-speed current that generates a thrust is applied to the constant-speed coil in the same direction (left to right) as the direction of movement of the hammerbank, and constant-speed control of constant-speed movement according to the printing speed is performed. The constant speed control is performed up to a position X2 at which the repulsive force from the reversing urging means starts to act. From the position X2 where the repulsive force from the reversing urging means starts to act to the deceleration start position X3, a speed-increasing current is applied to the reversing coil in a direction opposite to the deceleration current, so that the repulsive force from the reversing urging means is canceled. Generate thrust. Note that X3 is a value determined for each print speed setting. At this time, the speed-up current is increased as the repulsive force from the reverse biasing means increases. The profile of the speed-up current is determined for each print speed setting.

From the deceleration start position X3, a deceleration current is supplied to the inversion coil to perform deceleration control.

After the inversion, an accelerating current is applied to the inversion coil,
Performs hammerbank acceleration control. When the speed of the hammerbank is accelerated to -V1 (a value determined for each print speed setting), a suppression current is applied to the reversing coil in a direction opposite to the acceleration current to generate a thrust in a direction to cancel the urging force. The suppression current is supplied to a position X2 where the urging force from the reversing urging means no longer acts. At this time, the suppression current decreases as the urging force from the reversing urging means decreases. The profile of the suppression current is determined for each print speed setting. Next, the same direction as the shuttle movement direction (right → left) on the constant velocity coil
Is supplied with a constant velocity current which generates a thrust, and constant velocity control of constant speed movement according to the printing speed is performed.

The constant speed control is performed up to a position X1 at which the repulsive force from the reversing urging means starts to act.

From the position X1 where the repulsive force from the reversing urging means starts to act to the deceleration start position X0, a speed-increasing current is applied to the reversing coil in a direction opposite to the deceleration current to reduce the repulsive force from the reversing urging means. Generates thrust in the direction of cancellation. In addition,
X0 is a value determined for each print speed setting. At this time,
The speed-up current increases as the repulsive force from the reversing biasing means increases. The profile of the speed-up current is determined for each print speed setting. From the deceleration start position X0, a deceleration current is supplied to the inversion coil to perform deceleration control. After the reversal, the same control is repeated.

[0033]

According to the linear motor shuttle mechanism provided with the biasing means at the time of the inversion of the hammerbank, the shuttle control method according to the present invention is implemented, whereby the speed stability of the constant velocity movement section of the hammerbank is improved. Printing quality and printing speed can be easily improved.

[Brief description of the drawings]

FIG. 1 shows a speed waveform and a coil driving current waveform of a hammerbank in the present invention.

FIG. 2 shows an inversion coil driving circuit according to the present invention.

FIG. 3 is a flowchart of hammerbank driving according to the present invention.

FIG. 4 is a schematic side view showing an example of a shuttle mechanism using a linear motor.

FIG. 5 shows a hammerbank speed waveform and a coil drive current waveform.

FIG. 6 shows an energizing section for each print speed setting and a speed waveform.

FIG. 7 shows a coil driving current and a speed waveform of a hammerbank in a conventional technique.

[Explanation of symbols]

10 is a hammer bank, 11 is a guide shaft, 12 is a linear bearing, 20 is a linear motor unit, 21 is a coil, 22
Is a reverse coil, 23 is a constant velocity coil, 24 is a magnet,
30 is a reversing mechanism, 31 is a timing belt, 32 is a timing pulley, 40 is a spring, 50 is a position detection sensor,
Reference numeral 60 denotes a shuttle control circuit, and reference numeral 70 denotes a shuttle drive circuit.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masafumi Hiratsuka 1060 Takeda Hitachinaka City, Ibaraki Prefecture Within Hitachi Koki Engineering Co., Ltd.

Claims (7)

[Claims] 1. A hammer bank on which a plurality of printing elements are mounted, at least a magnet and a coil, and a drive current is supplied to the coil to reciprocate the hammer bank and reciprocate the hammer bank. A printing apparatus having a linear motor type shuttle mechanism provided with a reversing biasing means for biasing reversal of the hammer bank near both ends of the amplitude of the movement, wherein the hammer bank is reciprocating and the reversing is performed. A printing method characterized in that a driving current such that a thrust in a direction opposite to the urging force or the repulsive force is generated is applied to the coil in a section where the urging force from the urging means or the repulsive force is acting. Shuttle control method of the device. 2. A hammer bank on which a plurality of printing elements are mounted, at least a magnet and a coil, and a drive current is applied to the coil to reciprocate the hammer bank and reciprocate the hammer bank. A printing apparatus having a linear motor type shuttle mechanism provided with a reversing urging means for urging reversal of the reciprocation of the hammer bank near both ends of the amplitude of the motion, wherein the hammer bank reciprocates according to a printing mode. In a printing apparatus comprising a plurality of types of moving speed patterns, the drive timing of the drive current to the coil and the magnitude of the drive current for each print mode are preset for each speed pattern, and the hammer bank is reciprocating. And in a section where the biasing force from the reversing biasing means or the repulsive force is acting, A method for controlling a shuttle of a printing apparatus, characterized in that a drive current that generates a thrust in the direction is supplied to the coil. 3. The shuttle control method for a printing apparatus according to claim 1, wherein the acceleration of the hammer bank during the reciprocating movement of the hammer bank is completed in order to generate a thrust opposite to the urging force from the reverse urging means. A method for controlling a shuttle of a printing apparatus, characterized in that a suppression current is supplied in the vicinity of the start of constant speed from the start. 4. A shuttle control method for a printing apparatus according to claim 3, wherein said suppression current is reduced as the urging force from said reversing urging means decreases. 5. A shuttle control method for a printing apparatus according to claim 1, wherein a constant speed during reciprocating movement of said hammerbank is generated to generate a thrust opposite to a repulsive force from said reversing urging means. A shuttle control method for a printing apparatus, wherein a speed-up current is supplied in the vicinity of the start of deceleration from the end. 6. A shuttle control method for a printing apparatus according to claim 5, wherein said speed-up current is increased with an increase in a repulsive force from said reversing biasing means. . 7. A shuttle control method for a printing apparatus according to claim 4, wherein said coil for supplying an acceleration / deceleration current when said hammerbank is reversed can also be supplied with a current in a direction opposite to the acceleration / deceleration current. And a shuttle control method for the printing apparatus.