JP2009202504A - Shuttle control method of printing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shuttle control method which possibly reduces an operation time of a shuttle initialization in the range where a print quality is not lowered, and to improve an effective printing speed and reliability, even in generating a load for a shuttle due to an operation environmental temperature, etc. <P>SOLUTION: When an initialization operation of a shuttle mechanism has passed the time of initialization end determining change, the end of initialization is determined with a value reduced a control desired value. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a printing apparatus having a linear motor type shuttle mechanism, and more particularly to initialization control of a shuttle mechanism portion of a linear motor.

  FIG. 2 shows an example of a linear motor shuttle mechanism portion of a printing apparatus that reciprocates a hammer bank provided with a plurality of printing elements (dot printing hammers, etc.) by a linear motor type shuttle mechanism.

  The hammer bank 10 on which a plurality of printing elements are mounted is supported by a linear motion bearing 12 and reciprocates on the guide shaft 11. The linear motor unit 20, which is a power source for reciprocal operation, includes at least a coil 21 and a magnet 24, and the coil 21 generally includes an inversion coil 22 and a constant velocity coil 23. The hammer bank 10 and the coil 21 are connected to at least one timing belt 31 and can be shuttled by power from the linear motor unit 20 by a reversing mechanism unit 30 including at least one pair of supported timing pulleys 32. It is configured as follows.

  In the reciprocating reciprocation of the hammer bank 10 and the coil 21, the position detection sensor 50 attached to the movable part calculates the position and reciprocating speed of the hammer bank 10 and operates on a predetermined reciprocating speed curve. . The control is performed by a shuttle control circuit 60 that changes the value of the current supplied to the coil 21, a thermistor 61 that detects the operating environment temperature, and a shuttle drive circuit 70 that supplies current to the coil 21.

  The printing paper is mounted facing the hammer bank 10 and is conveyed by a paper feeding means (not shown). Then, in the course of the reciprocating operation of the hammer bank 10, printing is performed by driving the printing element toward the printing paper via the ink ribbon.

Next, the hammer bank speed waveform and coil drive current of the linear motor shuttle mechanism are shown in FIG.
The shuttle operation of the hammer bank is divided into a reverse section and a constant speed section as shown in the speed waveform. In the inversion section, the reversing coil 22 is energized to perform deceleration control and acceleration control, and in the constant speed section, the constant speed coil 23 is energized to perform constant speed control of constant speed movement. Further, in order to ensure the stroke amount necessary for printing, reverse position control is performed in which the deceleration start positions P1 and P2 are moved to adjust both ends XR and XL (referred to as reverse positions) of the amplitude (see Patent Document 1). ).

In such a printing apparatus, in order to ensure printing speed and quality, a shuttle initialization operation is generally performed before the start of printing. The main purpose of the shuttle initializing operation is to obtain appropriate values for the drive currents of the reversing coil and the constant velocity coil in order to perform a shuttle reciprocating operation that is stable at a specified shuttle speed and a cycle corresponding to a plurality of types of printing modes.

  FIG. 4 shows a schematic flowchart at the time of shuttle initialization operation. First, when shuttle initialization is started, the shuttle control described in FIG. 3 is performed. When the shuttle is driven for one stroke, the control shifts to initialization control. The initialization control includes constant speed section control, reverse position control, and reverse section control.

  In the constant speed section control, the current of the constant speed coil energized in the constant speed section is increased or decreased so that the time of the constant speed section is within the target time range. In the reverse position control, the deceleration start position is adjusted so that the left and right reverse positions are within the target range. In the inversion section control, the current of the inversion coil energized in the inversion section is increased or decreased so that the time of the inversion section falls within the target time range.

  In these controls, a control completion flag is set when the controlled object falls within the target range. If the control target is outside the target range, initialization is continued. However, because initialization control becomes difficult due to mechanical load, etc., and the operation time may be longer than usual, the control adjustment values (reverse / constant current, deceleration start position) If the control object is ready to print, the control completion flag is set. When the above control is performed and all the control completion flags are set, the initialization is finished and printing is started. If all the control completion flags are not set and the shuttle initialization operation does not end within the time limit, a shuttle error is reported to the host.

  When the control adjustment value becomes the limit value and initialization is completed, the printing speed at the start of printing may be less than the specified speed, but since it is controlled to always operate with the ideal curve, it is gradually specified. Transition to speed.

JP 2000-52599 A

  Since the shuttle initialization operation is performed before the start of printing, if the shuttle initialization operation time becomes longer, the effective printing speed is reduced. Therefore, it is essential to shorten the shuttle initialization time as much as possible. However, in the conventional control, the mechanism load increases, the motor thrust fluctuates, and the like due to a change in environmental temperature, etc., so that the control becomes difficult and the shuttle initialization time becomes extremely long.

  As described in the background art, when the limit value is reached in each control of shuttle initialization control, if it is in a printable state even outside the control target range, the printing speed is somewhat slow. However, it is assumed that the control has been completed and printing is started. However, this control makes it difficult to generate a time-out error due to a defective shuttle operation, and does not shorten the initialization time of the shuttle.

  It is an object of the present invention to shorten the shuttle initialization operation time as much as possible and improve the effective printing speed and reliability as long as the print quality is not deteriorated even when a load is applied to the shuttle due to the operating environment temperature or the like. It is to provide a shuttle control method for a printing apparatus.

In order to achieve the above object, a first means of the present invention includes a hammer bank having a plurality of printing elements mounted thereon, at least a magnet and a coil, and the hammer bank is formed by supplying a drive current to the coil. In a printing apparatus having a linear motor shuttle mechanism that reciprocates,
When the initialization operation of the shuttle mechanism has passed the initialization end determination switching time, the end of initialization is determined with a value obtained by relaxing the control target value.

  According to a second means of the present invention, in the first means, the initialization end determination is performed step by step based on a plurality of initialization end determination switching times and a relaxed target value.

  According to a third means of the present invention, there is provided a reverse biasing means for biasing the reversal of the reciprocation of the hammer bank in the vicinity of both ends of the amplitude in the reciprocation of the hammer bank in the first or second means. It is characterized by.

  The present invention is configured as described above, and the shuttle initialization operation time is shortened as much as possible within the range in which the print quality is not deteriorated even when a load is applied to the shuttle due to the operating environment temperature or the like. Can be improved.

  Next, examples of the present invention will be described. Since the configuration of the shuttle mechanism is the same as that described in the background art, the description thereof is omitted.

FIG. 1 is a schematic follow chart of shuttle initialization control in the present invention.
Print data is received from the host computer, and the shuttle initialization operation is started. In the shuttle initialization control, constant speed section control, reverse position control, and reverse section control are performed for each shuttle stroke. In each control, it is detected whether a target range, for example, ± 1% of the target value, is satisfied. If the target range is satisfied, each control completion flag is set. If the target range is not satisfied, execute each control adjustment process, and if the control adjustment values (reverse / constant current, deceleration start position) are the limit values and the control target is in a printable state Each control completion flag is set.

  Next, if the limit value has not been reached, first check whether the shuttle initialization operation time has passed the preset initialization end determination switching time, and if the switching time has not elapsed, the initialization operation Continue. When the switching time has already passed, the control is compared with a value obtained by relaxing the target value in each control, for example, + 1% and -5% of the target value, and if within the range, the control completion flag is set. This relaxed target value may be set in consideration of the balance of how much the printing speed is allowed to fall within a range where the printing quality is not lowered and how much the initialization time is shortened.

  In addition, multiple initialization end determination switching times and relaxed target values are created, and with the end determination switching time, the initialization end determination is performed step by step with a value that increases the target amount relaxation amount. It is also possible to shorten the initialization time while suppressing the amount of decrease in the printing speed as much as possible.

  Note that, as a configuration of the shuttle mechanism section, in a linear motor type shuttle mechanism section provided with a reversal biasing means for biasing the reversal of the reciprocating movement of the hammer bank in the vicinity of both ends of the amplitude of the reciprocating motion of the hammer bank, Similar shuttle control is feasible.

It is a schematic flowchart at the time of shuttle initialization operation | movement in this invention. It is a schematic side view which shows an example of the shuttle mechanism using a linear motor. It is a velocity waveform of a hammer bank and a coil drive current waveform diagram in the background art. It is a schematic flowchart at the time of shuttle initialization operation | movement in background art.

Explanation of symbols

  10 is a hammer bank, 11 is a guide shaft, 12 is a linear bearing, 20 is a linear motor section, 21 is a coil, 22 is a reversing coil, 23 is a constant speed coil, 24 is a magnet, 30 is a reversing mechanism section, and 31 is timing. A belt, 32 is a timing pulley, 50 is a position detection sensor, 60 is a shuttle control circuit, 61 is a temperature detection circuit, and 70 is a shuttle drive circuit.

Claims (3)

In a printing apparatus having a shuttle mechanism of a linear motor system having a hammer bank mounted with a plurality of printing elements, at least a magnet and a coil, and reciprocatingly moving the hammer bank by supplying a driving current to the coil.
A shuttle control method for a printing apparatus, characterized in that, when the initialization operation of the shuttle mechanism has passed the initialization end determination switching time, the end of initialization is determined with a value obtained by relaxing the control target value.   The shuttle control method for a printing apparatus according to claim 1, wherein the initialization end determination is performed step by step based on a plurality of initialization end determination switching times and a relaxed target value.   3. The shuttle control method for a printing apparatus according to claim 1, further comprising reverse biasing means for biasing reversal of the reciprocation of the hammer bank in the vicinity of both ends of the amplitude in the reciprocation of the hammer bank. A shuttle control method for a printing apparatus.

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