JPH03197071A - Recorder - Google Patents

Abstract

PURPOSE:To obtain a recorder free from an error in moving a carriage caused by a backlash by a method wherein a drive force transmission delay amount caused by a backlash or the like in the reciprocation of the carriage is corrected before the carriage is moved. CONSTITUTION:When a carriage 2 is reversed from a space direction F to a backspace direction R upon completion of printing in the space direction F, the reversed direction is discriminated. With the reversing instruction from the space direction F to the backspace direction R, a first correction is conducted by adding the set amount in a second register 12b, i.e. the step num ber corresponding to a drive force transmission delay amount. Thereafter, the backspace direction R is stored in a register 12a as a carriage travel direction, the carriage 2 is moved in accordance with the instructed carriage travel am ount, and printing is conducted after the carriage 2 comes to a stop. At this time, a carriage motor 8 is driven in a direction Cr by the sum of the travel amount and the transmission delay amount. As a result, the amount of backlash in reversing from the space direction F to the backspace direction R is corrected in the first correction. A printing position in traveling in the backspace direction R has no shift from a printing position in traveling in the space direction F.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a printing apparatus that prevents printing position shift by correcting backlash of a carriage drive system.

<Prior art> Printing devices such as electronic typewriters are widely used today, but these printing devices have a recording head mounted on a carriage and print while moving the carriage in the space direction, so-called serial printing devices. A type recording method is used. These devices generally print when the carriage is moved in one direction, but in recent years, in order to shorten printing time, printing is only performed when the carriage is moved in the space direction. First, a so-called bidirectional printing method has been developed that prints even when moving in the backspace direction.

In the bidirectional printing method, the printing positions of characters printed when the carriage is moved in the space direction and characters printed when the carriage is moved in the backspace direction may be misaligned. It is well known that this is often caused by backlash when the driving force of the carriage drive motor is transmitted to the carriage via a gear.

Therefore, conventionally, as shown in FIG. 13, a timing belt 52 is stretched between a motor pulley 51 attached to a carriage motor 50 and a driven pulley (not shown), and a carriage 54 on which a recording head 53 is mounted is attached to the timing belt 52. 5
2, and the carriage 54 is moved back and forth by rotating the motor 50 in forward and reverse directions. In this configuration, the pulley 51 is attached directly to the motor 50, and the driving force is directly applied to the carriage 54 without going through a gear train.
, it is possible to eliminate movement errors due to backlash.

As another configuration, as shown in FIG. 14 (al), the driving force of the motor 50 is reduced by meshing a pulley gear 56 with a motor gear 55 attached to the carriage motor 50, and as shown in FIG.
As shown in bl, backlash is absorbed by using a so-called two-tooth gear in which two gears 56a and 56b are biased by a spring so as to be deviated by the amount of backlash. With this configuration, since the driving force of the motor 50 is decelerated and transmitted to the carriage 54, the motor torque can be reduced and the motor 50 can be made smaller.

<Problems to be Solved by the Invention> However, in the above configuration, in the former configuration in which the motor pulley 51 is directly attached to the motor 50,
The drive torque of the carriage motor 50 must be increased, and for this purpose a large motor must be used as the carriage motor 50, and the belt 5 must be large.
2 must be tightened strongly so that the tension is approximately 8 kg, and for this purpose it is necessary to use a bearing in the pulley bearing to reduce friction. be.

In the latter configuration using a two-tooth gear, a small carriage motor 50 can be used, but the cost is high because a two-tooth gear with a complicated structure must be used. This is similar to the former in that the belt 52 must be strongly supported, so there are problems such as the need to use expensive bearings and the need to increase the rigidity of the frame.

The present invention is intended to solve the above-mentioned conventional problems, and its purpose is to provide a recording device that eliminates carriage movement errors due to backlash using a small motor torque without using a two-tooth gear as in the conventional case. This is what we intend to provide.

<Means for Solving the Problems> A typical means according to the present invention for solving the above problems includes a carriage that can reciprocate in a space direction and a backspace direction, and a carriage that is mounted on the carriage and records on a recording sheet. a pulse motor capable of forward and reverse rotation for moving the carriage to a recording position; a driving force transmitting means for transmitting the driving force of the pulse motor to the carriage; When the moving direction of the carriage is reversed from the space direction to the backspace direction, the drive amount of the pulse motor is increased by a predetermined amount compared to normal to compensate for the amount of transmission delay of the drive transmission means due to the reversal of the carriage. a first correction process; a second correction process for offsetting the correction amount of the first correction process when the moving direction of the carriage is reversed from the backspace direction to the space direction after the first correction process; The present invention is characterized by the provision of a control means for performing a third correction process of moving the carriage in the back space direction by more than the first correction amount after the second correction process, and then moving the carriage in the space direction.

Further, the other means includes a detection means for detecting the reference position of the carriage, and when setting the transmission delay amount of the drive transmission means, the output of the detection means is driven by driving the pulse motor. The carriage is moved until the expected value is reached, and then the carriage is moved in the opposite direction to the moving direction until the output value of the detection means is reversed, and the motor drive amount is equal to the transmission delay amount of the drive transmission means. It is characterized by

Effect> In the above means, the reciprocating movement of the carriage can be accurately managed by correcting the amount of drive transmission delay due to backlash or the like when the carriage is reciprocated and moving the carriage. Therefore, even if so-called bidirectional incremental recording is performed when the carriage is moved back and forth, recording can be performed without causing a recording position shift.

<Embodiment> Next, an embodiment of the present invention will be described in which the above means is applied to a daisy-wheel recording type electronic typewriter which performs bidirectional printing when the carriage moves back and forth.

[First example]

FIG. 1 is an explanatory diagram of the configuration of a recording device, and FIG. 2 is an explanatory diagram of the entire configuration of an electronic typewriter.

(Overall Description) First, the overall configuration of the device will be explained. In the apparatus, when recording information is input by operating the keyboard K shown in FIG. 2, the information is displayed on the display D, and when the recording sheet 6 is set after inputting the information and the recording start key is operated, the recording apparatus P is driven. The input information is recorded on the recording sheet 6.

The recording apparatus P uses a daisy-wheel recording method in this embodiment, and as shown in FIG. is installed. The carriage 2 is configured to be movable while being guided by a guide shaft 4 and one end surface 5a of the main body frame 5, and by moving the carriage 2 to a desired position and driving the recording means 3, printing is performed on the recording sheet 6. The sheet conveying means 7 conveys the recording sheet 6 on which negative lines have been printed in the direction of arrow a. Incidentally, in this embodiment, the recording is configured to perform so-called bidirectional incremental recording, in which recording is performed when the carriage 2 moves in either the space direction F or the backspace direction R.

The carriage 2 is connected to a carriage motor 8 consisting of a pulse motor via a driving force transmission means 9,
It is configured to reciprocate by the forward and reverse rotation of the carriage motor 8, and at that time, drive control is performed while taking into consideration and correcting backlash generated in the driving force transmitting means 9 by a control means to be described later.

Next, the configuration of each part will be specifically explained.

(Ink ribbon cassette) The ink ribbon cassette 1 has a recess la formed in the center of the front part of the container, and a long ink ribbon lb is wound around a supply spool (not shown) provided inside the container, and the ink ribbon cassette 1
It is wound around the take-up spool so that it is exposed at point a. This take-up spool is connected to a drive transmission roller 1c, and the roller lc is configured to wind up the ink ribbon lb by being engaged with a take-up shaft to be described later and being driven and rotated. Furthermore, positioning bosses ld are provided on both sides of the cassette l to position the cassette 1 when loading the cassette 1 into the carriage 2.

(Carriage) The carriage 2 is configured to mount the recording means 3 and to move with the ink ribbon cassette 1 loaded therein. Hooks 2b that are rotatable around a shaft 2a are provided on both sides of the carriage 2, and the hooks 2b are biased by a tensioning respring 2C, and the positioning boss 1d of the ink ribbon cassette 1 is attached to the hook 2b. 2b
When the ink ribbon cassette l is locked to the upright wall 2d of the carriage 2, the ink ribbon cassette l is pushed and fixed to the upright wall 2d of the carriage 2.
The ink ribbon 1b exposed therefrom is positioned between a printing wheel 3a and a recording sheet 6, which will be described later.

Further, a take-up shaft 2e is provided at a predetermined position of the carriage 2, and is configured so that when the ink ribbon cassette 14 is loaded into the carriage 2, it is fitted and locked with the drive transmission roller lc force take-up shaft 2e.

Further, a four-motor motor 2g is connected to the winding shaft 2e via a set of gears 2f, and the ink ribbon 1b is wound onto a winding spool by driving the motor 2g.

The carriage 2 is slidably fitted onto a guide shaft 4 attached to the main body frame 5, and is movably attached along the guide shaft 4 and the frame end 5a.

(Recording Means) Next, the recording means 3 uses a daisy type element in this embodiment, and a hammer 3c operated by a type wheel 3a and a solenoid 3b is mounted on the carriage 2.

The type wheel 3a has type letters arranged radially around a rotating shaft, and is configured to rotate when driven by a wheel motor 3d connected to the rotating shaft.

Therefore, the type wheel 3a is rotated to make the desired type face the hammer 3c, and the hammer 3c is driven to strike the ink ribbon lb so that the desired type is attached to the recording sheet 6 whose back surface is supported by the platen roller 7a. It is printed.

(Sheet conveyance means) As shown in FIG. 1, the sheet conveyance means 7 is provided with a platen roller 7a in a position opposite to the operating axis of the hammer 3c and in the moving area of the carriage 2. 7a is configured to be rotated by a platen motor 7b. A guide 7c is attached around the platen roller 7a, and several pinch rollers 7d are attached so as to be in pressure contact with the roller 7a.

Therefore, when the platen roller 7a is driven to rotate, the recording sheet 6 is guided by the guide plate 7c in cooperation with the pinch roller 7d, and passes between the platen roller 7a and the ink ribbon lb in the direction of the arrow a in FIG. It is transported to

(Driving force transmission means) The driving force transmission means 9 is for transmitting the driving force of the carriage motor 8 to the carriage 2, and as shown in FIG. 1, there are a driving pulley 9a and a driven pulley 9b at both ends of the carriage movement range. are attached, and both pulleys 9a, 9.
A timing belt 9c is loosely stretched between the carriages 2 and 3b with a tension of approximately 0.7 kg, and this belt 9c is connected to the carriage 2. Further, a pulley gear 9d consisting of a single gear is integrally attached to the drive pulley 9a, and this gear 9d meshes with a motor gear 9e attached to the drive shaft of the carriage motor 8.

As a result, when the carriage motor 8 rotates in the forward and reverse directions, its driving force is reduced by the gears 9d and 9e and transmitted to the carriage 2, so that the carriage 2 reciprocates along the guide shaft 4.

(Backlash of Driving Force Transmitting Means) Backlash that occurs when the driving force of the carriage motor 8 is transmitted to the carriage 2 will now be explained.

In the driving force transmission means 9, the pulley gear 9d and the motor gear 9e mesh with each other with some backlash.

For example, when the motor gear 9e is rotated in the C9 direction shown in FIG. 3 1al in order to move the carriage 2 in the space direction F, the right side of the teeth of the motor gear 9e contacts the left side of the teeth of the pulley gear 9d. The driving force is transmitted. At this time, a gap Gt is created between the right side surface of the teeth of the pulley gear 9d and the left side surface of the teeth of the motor gear 9e.

Furthermore, when the motor gear 9e is rotated in the C2 direction shown in FIG. 3(b) in order to move the carriage 2 in the backspace direction R, the left side of the teeth of the motor gear 9e is brought into contact with the right side of the teeth of the pulley gear 9d. The driving force is transmitted through contact. At this time, a gap G is created between the left side surface of the teeth of the pulley gear 9d and the right side surface of the teeth of the motor gear 9e.

Therefore, when the carriage 2 is reversed from the space direction F to the backspace direction R, both gears 9d and 9e change from the state +a+ in FIG. 3 to the state shown in FIG.

However, even if the carriage motor 8 is rotated in the Cr direction upon reversal, no driving force is transmitted while the motor gear 9e rotates by the amount of the gap Gf.

On the other hand, when reversing the carriage 2 from the back space direction R to the space direction F, both gears 9d.

9e is the reverse of the above, from the state of Figure 3 1b) to Figure 3 +a+
transition to the state of However, even in this case, even if the carriage motor 8 is rotated in the C1 direction upon reversal, no driving force is transmitted while the motor gear 9e rotates by the amount of the gap Gr.

As described above, when the carriage 2 moves back and forth, backlash exists between the pulley gear 9d and the motor gear 9e.

Further, in the driving force transmission means 9, the belt 9c may be bent when the carriage 2 moves.For example, as shown in FIG. 4(al), the carriage motor 8
When rotating the carriage 2 in the Cf direction and moving the carriage 2 in the space direction F, a deflection IDt may occur in the lower part of the belt 9c.

Conversely, when the carriage motor 8 is rotated in the C1 direction to move the carriage 2 in the backspace direction R as shown in FIG. 4 (bl), the upper part of the belt 9c may be bent.

Therefore, if the belt 9c is bent as described above, when the carriage 2 is reversed from the space direction F to the backspace direction R, from the state of FIG. 4 (al) to the state of FIG. However, the carriage motor 8
Even if the motor 8 is rotated in the 01 direction, the driving force of the motor 8 will not be transmitted to the carriage 2 until the deflection is removed.

Similarly, when the carriage 2 is reversed from the back pace direction R to the space direction F, the state shown in FIG. 4(b) is changed to the state shown in FIG. Even if the carriage 2 rotates in this direction, the driving force of the motor 8 will not be transmitted to the carriage 2 until the deflection is removed.

Therefore, if the belt 9C is bent when the carriage 2 moves, backlash will also exist between the belt 9c and the pulley gear 9d.

The backlash caused by the gaps Gy, C;- or the deflection amounts Dt, D- becomes the amount of delay in transmission of the driving force.

(Control Means) Next, the control means is explained. This control means drives and controls the carriage motor 8 so as to correct the influence of backlash and the like occurring in the driving force transmitting means 9.

Its configuration is as shown in the block diagram of FIG.

In FIG. 5, CPU10 is a central processing unit consisting of a microcomputer, etc., which reads programs and various data from a ROM 11, etc., which will be described later, performs necessary calculations and judgments, and performs various controls.

ROMII is read-only memory and CP
It stores various programs (for example, the program shown in FIG. 6) and various data for the operation of Ul0.

RAM12 is random access memory, C
It consists of a working area where PLJIO temporarily stores data in commands and calculation results, a buffer area where various data input from keyboard A etc. is stored, a text area where documents are stored, etc. This RAM1
2, a first register 12a for storing the moving direction of the carriage 2 and a second register 12b for storing the correction amount for correcting the above-mentioned backlash when the carriage 2 is reversed are secured in advance. has been done.

In this embodiment, the register 12a is set to indicate the space direction F, and the register 12b is set to either the gap Gf or the deflection Dr, or the sum of both,
That is, the number of motor steps corresponding to the driving force transmission delay amount is set.

These ROM II, RAM 12, the above-mentioned keyboard K and recording device P are connected to the CPU10 via the CPU bus 13.
It is connected to the.

The CPU10 reads a program stored in the ROMII via the CPU bus 13 by a reset operation such as powering on the device, executes the program according to the program, and if there is an input instruction from the keyboard K, it also executes the instruction. Analyze and if necessary drive and control the recording device P to record desired characters, store the input document in the RAM 12, read the input document from the RAM 12 and edit it, or record the document in print. control actions such as

Next, the carriage drive control procedure by the control means is carried out in a sixth manner.
This will be explained with reference to the flowchart shown in the figure.

First, in step Sl, in order to detect the reversal of the moving direction of the carriage 2, the instructed moving direction and the first register 12a are
The direction of movement is compared with the previously stored direction of movement, and if they are the same direction, the process advances to step S2.

In step S2, the content of the instructed moving direction is updated in the first register 12a, and the process proceeds to step S3, where the carriage motor 8 is driven and controlled to move the carriage 2 in the instructed moving amount and direction during printing.

Upon completion of this movement, in step S4, the recording means 3
is driven to perform predetermined printing on the recording sheet 6. Then, in step S5, it is determined whether recording has ended or not, and if there is next printing, the process returns to step S1.

Next, when the printing in the space direction F is completed and the carriage 2 is reversed from the space direction F to the backspace direction R, the process proceeds from step St to step S6, and the reversal direction is changed from the space direction F to the bank space direction R. It is determined whether or not there is, and if it is a reversal instruction from the space direction F to the backspace direction R, the process advances to step S7 and a first correction process is performed.

This first correction process is a process of adding a step number corresponding to the amount set in the second register 12b, that is, the amount of driving force transmission delay.
Next, the process proceeds to step S2, where it is stored in the register 12a that the carriage movement direction is the backspace direction R.
Furthermore, printing is executed after the carriage 2 is moved and stopped according to the carriage movement amount instructed in step S3. At this time, the carriage motor 8 is driven in the C1 direction by an amount equal to the amount of movement plus the amount of transmission delay.

As a result, the backlash when reversing from the space direction F to the backspace direction R is corrected in the first correction process, and the print position moves in the space direction F while moving in the backspace direction R. This means that no misalignment will occur with respect to the printing position.

Incidentally, since the moving direction of the carriage 2 is memorized in step S2, even if the moving direction instruction in the next printing is the same backspace direction R, the process proceeds to step S2 due to the determination in step Sl. As a result, the correction operation is not performed excessively, and as described above, printing is performed without positional deviation even when the carriage 2 moves in the backspace direction R.

Next, when the printing while moving in the backspace direction R is completed and the carriage 2 is reversed from the backspace direction R to the space direction F to record, the process proceeds from step S1 to step S6, and the reverse direction is the backspace direction. Direction R
When it is determined that the direction is space direction F, step s
Proceed to step 8 to perform second correction processing.

This second correction process is a process for offsetting the correction amount of the first correction process. Since the first correction process is performed in step S7, the movement of the carriage 2 in the bank space direction R is determined by the transfer position of the carriage 2, which has driven the carriage motor 8, according to this correction value, and the movement of the carriage motor 8. There is a phase shift between the phase position and the phase position.

Therefore, when the carriage 2 is reversed from the backspace direction R to the space direction F by the second correction process, the carriage motor 8 is moved in the C1 direction (in the C1 direction) by the amount set in the second register 12b, that is, the same amount as the first correction amount. 1) drive and rotate in the opposite direction of the correction process.

As a result, the positional deviation is canceled out, and the physical transfer position of the carriage 2 and the phase position of the carriage motor 8 are completely eliminated.

There is no problem theoretically with this second correction process, but in this embodiment, after the second process is completed, step S9
Then, the third correction process is performed, which is a process for ensuring that the driving force of the carriage motor 8 is transmitted to the carriage 2, and is a process for positioning the carriage 2. That is, when a relatively large backlash exists in the drive transmission means 9, the second correction process actually causes the motor gear 9e and the pulley gear 9d to change as shown in FIG. 3+a).
belt 9c.
There is also a possibility that the amount of deflection will not change to the state shown in FIG. 4 1al. Therefore, in this embodiment, the above-mentioned fear is completely removed by performing the third correction process, and the drive transmission means 9 is shifted to the state shown in FIGS. 3(a) and 4(al) at the reversal reference position, This is to reliably transmit the driving force of the carriage motor 8 in the C1 direction to the carriage 2.

The third correction process is performed by the number of steps equal to or greater than the correction amount performed in the first correction process (the gap G in FIG. 3 (8) and the gap G in FIG.
(the number of steps equal to or greater than the sum of the deflections), the carriage motor 8 is driven in the Cr direction, and the carriage motor 8 is further driven in the C1 direction by the same number of steps as this number of steps at a slower speed than usual. This ensures that the driving force transmitting means 9 is at the reversal reference position as shown in FIGS.
In this state, the driving force is reliably transmitted.

Further, at this reversal reference position, no deviation occurs between the transfer position of the carriage 2 and the phase position of the carriage motor 8.

After completing the third correction process as described above, step S
2 and subsequent steps to perform recording in the space direction F. At this time, since the moving direction of the carriage 2 has been memorized in step S2, if the moving direction instruction for the next printing is the same space direction F, does not perform excessive correction operations.

By driving and controlling the carriage motor 8 as described above, even if backlash or the like exists, the characters recorded by bidirectional recording by the recording means 3 are recorded without relative positional deviation.

Note that the correction amount in the first correction process is based on the pulley gear 9d.
The amount of backlash of the motor gear 9e and the amount of deflection of the heald 9c are determined by the relationship between the gears 9d and 9e and the heald 9.
It can be easily determined by testing the tension of c, etc., and may be set appropriately depending on each case.

[Second example]

In the first embodiment described above, an example was shown in which the drive of the carriage motor 8 is controlled using the CPU10, but the carriage drive control means can also be constructed without using this.

In FIG. 6, an example of which is shown in FIG. 7, CMD is a carriage transfer instruction means, and the carriage transfer direction is instructed from the printing control means of the recording device Hp. For example, moving the carriage 2 after printing and recording characters entered from the keyboard K, storing previously input text and recording and printing a desired text, etc. This indicates the amount and direction of transfer.

The control means operates according to this instruction.

Reference numeral 14 denotes a transport direction reversal detection means for detecting reversal of the carriage transport direction, which compares the previously designated transport direction with the currently designated carriage transport direction and controls control 1#l if the directions are the same. The amount and direction of movement of the carriage 2 are instructed to the carriage drive control means 15 by Ls. This carriage drive control means 15 operates a carriage motor 8 according to the commanded transport amount and transport direction so as to move the carriage 2 by a predetermined amount in response to the command.
The number of drive steps and motor sliding switching direction are determined in order to drive the motor by a predetermined amount, and the motor drive circuit 16 performs voltage conversion or voltage-current conversion through the control 411CNT, and the carriage motor 8 is driven in steps by the control line DRV.

Here, a case where the carriage transfer instruction is different from a previously instructed transfer direction, that is, a case where the carriage 2 is reversed will be described.

■In case of reversal from space direction F to backspace direction R When the transfer direction reversal detecting means 14 determines that the previous transfer direction was the space direction F and the currently instructed transfer direction is the backspace direction R, the transfer direction reversal detecting means 14 controls the A command is given to the first Sakaki correction means 17 through the line L1 to perform the first correction process.

As explained in the first embodiment, this first correction process adds a correction value to the carriage movement amount instructed from the carriage movement amount indication CMD, and adjusts the gap G in FIG. ) Bell) Deflection measure of 9c.

The transfer amount and transfer direction are instructed to the carriage drive means 15 through the control line Lt so as to cancel out either or both of them. The carriage drive means 15 receiving this command drives and controls the carriage motor 8 via the motor drive circuit 16. This moves the carriage 2 in the space direction F.
Backlash is corrected when the characters are reversely transferred from the to the backspace direction R, and positional deviation between characters printed in the space direction F and characters printed in the backspace direction R is prevented.

■ Reversal from backspace direction R to space direction F Next, when the transfer direction reversal detection means 14 determines that the previous carriage transfer direction was backspace direction R and the currently instructed transfer direction is space direction F. Then, a second correction process is commanded to the second correction means 18 via the control line.

As explained in the first embodiment, this second correction process is for making the position when transported in the space direction F equal to the phase 1 of the carriage motor 8 according to the correction amount corrected in the first correction process. This is a process in which a command is sent from the second correction means 18 to the carriage drive control means 15 via a control line to correct the phase position of the carriage motor 8.

Next, the second correction means 18 instructs the third correction means 19 to perform a third correction process via the control line Lh, and the carriage drive control means 15, which receives this command via the control line Lh, controls the carriage motor. 8 is controlled and driven. In this third correction process, the carriage motor 8 is driven in the Cr direction by an amount slightly larger than the correction amount in the first correction process, and then the carriage motor 8 is driven in the Cf direction by the same amount more gently than usual. This allows the carriage 2 to be positioned.

When the third correction process is completed, printing is performed while moving the carriage 2 at a normal speed according to the carriage movement amount instructed by the carriage movement instruction means CMD.

Even with the control configuration described above, it is possible to eliminate backlash and the like occurring in the driving force transmission means 9 to the carriage 2, and to eliminate printing position deviation in bidirectional printing.

(Third Embodiment) In the above-mentioned first and second embodiments, the drive transmission means 9
Although the drive control was performed with the amount of backlash constant, as a third embodiment, an example will be described in which the amount of backlash is detected and drive control of the carriage is performed, taking into account that the amount of backlash changes.

Requiring high precision in the tension of the bell (9c) in the drive transmission means 9 will increase costs, and if these devices are used, the belt 9c will elongate, the motor gear 9e, the pulley gear 9d will wear out, or the pulley gear 9
It is conceivable that the amount of bank crash may change due to wear of the bearing portion.

Fig. 8 (al), (bl is a configuration example for detecting the amount of backlash, Fig. 8 (al is a front left enlarged view of the carriage drive system, Fig. 8 (bl is a top view) be.

As shown in the figure, a boss 20 is attached to the lower part of the carriage 2, and a detector 21 is attached to the frame 5 at the left end of the carriage 2. This detector 2
1 uses a photo ink lamp in this embodiment, and when the carriage 2 reaches the left reference position I, the boss 20 blocks the light irradiation part of the detector 21, and at this time the detector 21 is in the ON state. It is configured so that it can be detected.

As shown in FIG. 9, the configuration for detecting the amount of backlash using this detector 21 is as follows: The detector 21 is connected to the control means shown in the first embodiment via the CPU bus 13, and the state of the detector 21 is monitored. It is configured so that it can be detected by CPU10.

A program shown in the flowchart of FIG. 10 for detecting the amount of backlash based on the signal from the detector 21 is stored in the ROM II of the control means.

This backlash amount detection process is executed when the recording mechanism section is initialized during a reset operation such as when the apparatus is powered on.

The backlash amount detection processing procedure will be explained with reference to the flowchart of FIG. 10. First, in step 31G, it is determined whether or not the detector 21 has already detected the boss 20. At Sll, the carriage motor 8 is driven by a predetermined amount in the Ct force direction to move the carriage 2 by a predetermined amount in the space direction F shown in FIG. This amount of movement is the amount of movement at which the boss 20 is reliably separated from the detector 21 and the detector 21 is turned off. If the boss 20 is already separated from the detector 21 in step 310, the process proceeds to step 312, where the carriage motor 8 is moved in the C1 direction every step corresponding to the minimum resolution (for example, l steps in the case of a pulse motor). The carriage 2 is driven in the backspace direction R. This continues until the detector 21 detects the boss 20 in step S13. This step 312.51
3 is an operation for detecting the left reference position of the carriage 2.

Next, in step S13, when the detector 21 detects the boss 20, the process proceeds to step 314, where an initial value is set in the second register 12b that stores the backlash amount correction value.Next, the process proceeds to step S15, where the carriage motor 8 C1
The carriage 2 is moved in the space direction F by being driven in the direction corresponding to the minimum resolution.

Then, in step S16, the contents of the second register 12b are updated to store the drive step number as a correction value.Next, in step S17, the detector 21
0 is detected, that is, whether the carriage 2 has started moving or not. If the detector 21 detects the boss 20 (the carriage 2 is stopped 71!t), the process advances to step S15. Returning, the carriage motor 8 is continued to be driven minutely, and the accumulated amount is updated to the second register 12b as the backlash amount.

Then, when the detector 21 no longer detects the boss 20 in step SIT, that is, when the carriage 2 starts moving in the space direction F, the backlash amount detection process ends.

As mentioned above, step S12. Carriage 2 in S13
At the time when the left reference position of
The state shown in FIG. 4(b) is reached, and steps 314 to S1
At the time when the carriage 2 starts moving in the space direction F at step 7, the state shown in FIG. 3 (al) and FIG. Therefore, by storing the detected amount of backlash in the second register 12b and performing the drive control of the first embodiment described above using this amount as a correction amount, the amount of backlash will not change due to aging or the like. However, it is possible to always perform appropriate correction processing.

In this third embodiment, an example is shown in which a photo ink probe is used as the detector 21, but the detector 21 may be of any type as long as it can detect the movement of the carriage 2. For example, a mechanical contact may be used as the detector 21. You can do it like this.

Further, in the third embodiment, the left side reference position of the carriage 2 is detected, but the detector 21 is provided on the right side of the frame 5, and by detecting the right side reference position of the carriage 2, the amount of backlash is detected. In this case, the steps Sll, S12. S1
The driving direction of the carriage motor 8 in step 5 may be set in the opposite direction.

Furthermore, it goes without saying that the boss 20 and the detector 21 may be attached to the frame 5 and the detector 21 to the carriage 2, contrary to the third embodiment.

Note that the detector 21 can be a home position sensor for detecting the home position of the carriage 2 that is attached to most recording devices, and if this sensor is used, a special detector can be used. There is no need to provide

Further, the second register 12b may be set by performing the above-mentioned detection operation a plurality of times and taking the average.

[Fourth embodiment]

Next, the detector 21 of the third embodiment described above as the fourth embodiment
An example of detecting the amount of backlash by correcting the hysteresis characteristic will be shown.

Generally, the detector 21 often has hysteresis characteristics when changing from ON to OFF or from OFF to ON.

When the detector 21 has the hysteresis characteristic, the relationship between the detector 21 and the moving position of the carriage 2 described in the third embodiment will be as shown in FIG. 11. In this figure, the horizontal axis represents the moving position of the carriage 2, and the vertical axis represents the detector 21.
It represents the ON and OFF states of.

The solid line in FIG. 11 shows the detection state of the detector 21 when there is no hysteresis. That is,
The left reference position of the carriage 2 explained in the third embodiment is D.
If it is l, then this position.

When the carriage 2 moves in the space direction F, the detector 21 switches from ON to OFF and detects the movement of the carriage 2.

However, if the detector 21 has a hysteresis characteristic, the boss 2
Even if 0 moves away from the detector 21, the detector 21 will immediately
It does not go into the FF state, but goes into the OFF state after a certain period of time as shown by the broken line in FIG. At this time, the carriage 2 has already moved by an amount h and is at the position. Therefore, the first O
In the detection procedure shown in the figure, in addition to the actual backlash amount, the second register 12b stores the carriage 2
The amount of movement for one minute will be stored as the amount of backlash. Therefore, if the correction amount is set according to the amount stored in the second register 12, the correction amount will be equal to the above amount when bidirectional printing is performed. There is a risk of misalignment.

In order to solve this problem, in the fourth embodiment, the amount of backlash is detected by correcting the detection error due to the hysteresis characteristic.

The backlash amount detection procedure for this purpose is shown in the flowchart of FIG.

In FIG. 12, steps SIO to 317 are the detection of the left side reference position of the carriage 2 and the detection of the amount of backlash as described in the third embodiment.

In the processing up to step S17, an amount including an error due to the hysteresis characteristic is stored as a backlash amount in the second register 12b. So step 318
In this step, the amount of hysteresis error is corrected from the second register 12b that stores the amount, that is, the second register 1
A correction process is performed to subtract the error amount from the contents of 2b, and this is reset to the second register 12b as the backlash amount.

Detection based on the hysteresis characteristic - difference weighing is performed by the detector 21
This is due to the characteristics of , and can be easily determined by testing, so the measurement is ROMI! and may be stored in the RAM 12 in advance.

By detecting the amount of backlash as described above, even if the detector 21 has hysteresis characteristics, it is possible to accurately detect the amount of backlash, thereby preventing positional deviation during bidirectional printing. I can do it.

By configuring as in the first to fourth embodiments, even when there is backlash, it is possible to record without positional deviation during bidirectional printing by controlling the motor drive.

In the first to fourth embodiments described above, the daisy-wheel recording method was used as an example of the recording means.
The recording means need not be limited to this, and it goes without saying that other methods such as an inkjet recording method may also be used.

<Effects of the Invention> As described above, the present invention uses motor drive to correct backlash, etc. that occur in the drive force transmission means that transmits the drive force of the motor to the carriage, so that the occurrence of recording position deviation during bidirectional recording is avoided. can be prevented.

In addition, since the driving force of the motor can be transmitted to the carriage via gears, etc., the motor driving force can be decelerated. Therefore, a motor with a small driving torque can be used, and the motor can be made smaller to reduce costs and equipment. Miniaturization can be achieved.

Furthermore, as there is no need to tighten the belt strongly or use a two-tooth gear as in the past, mechanical durability is improved, and an inexpensive recording mechanism can be used, reducing the cost of the device. It is possible to plan.

Furthermore, if the amount of backlash, etc. is detected at any time and correction control is performed based on this, it is possible to more reliably prevent a recording position shift during bidirectional recording.

[Brief explanation of drawings]

FIG. 1 is a perspective explanatory diagram of a recording device according to an embodiment of the present invention, FIG. 2 is an external perspective explanatory diagram of an electronic typewriter using the recording device, and FIG. Illustration of backlash between pulley gears, Fig. 4 1
al, (bl is an explanatory diagram of the backlash between the pulley gear and the belt, FIG. 5 is a block diagram of the structure of the carriage drive control means, FIG. 6 is a flowchart showing the carriage drive control procedure, and FIG. 7 is a diagram for the second embodiment. A block diagram showing such carriage drive control means, FIG. 8 is Tal, (b
1 is an explanatory diagram of a third embodiment in which a detector and a boss are provided for detecting the left reference of the carriage, FIG. 9 is a block diagram showing a carriage drive control configuration according to the third embodiment, and FIG. 10 is a backlash amount detection diagram. A flowchart showing the procedure, FIG. 11 is a graph showing hysteresis characteristics in the fourth embodiment,
Fig. 12 is a flowchart showing the procedure for correcting the hysteresis characteristic and detecting the amount of backlash, and Figs. 13 and 14 (al and b) are explanatory diagrams related to the prior art. K is a keyboard, and D is an explanatory diagram. Display, P is recording device, l
is an ink ribbon cassette, 1a is a recess, lb is an ink ribbon, IC is a transmission roller, 1d is a positioning boss, 2 is a carriage, 2a is a shaft, 2b is a hook, 2c is a tension spring, 2d is an upright wall, 2e is a winding shaft , 2f is a set of gears, 2g is a ribbon motor, 3 is a recording means, 3a is a type wheel, 3b is a solenoid, 3c is a hammer, 3d is a wheel motor, 4 is a guide shaft, 5 is a main body frame, 5
a is an end surface, 6 is a recording sheet, 7 is a sheet conveying means, 7a
is a platen roller, 7b is a platen motor, 7c is a guide plate, 7d is a pinch roller, 8 is a carriage motor, 9 is a driving force transmission means, 9a is a driving pulley, 9b is a driven pulley, 9c is a timing belt, 9d is a pulley gear,
9e is the motor gear, 10 is the CPU, 11 is the ROM, 1
2 is RAM. 12a and 12b are registers, 13 is a CPU bus, 14 is a transfer direction reversal detection means, 15 is a carriage drive control means, 16 is a motor drive circuit, 17 is a first correction means, 18
2 is a second correction means, 19 is a third correction means, 20 is a boss, 2
1 is a detector.

Claims (2)

[Claims] (1) A carriage that can reciprocate in the space direction and the backspace direction, a recording means mounted on the carriage for recording on a recording sheet, and a pulse that can rotate forward and backward to move the carriage to a recording position. a motor; a driving force transmitting means for transmitting the driving force of the pulse motor to the carriage; and a driving force transmitting means for transmitting the driving force of the pulse motor to the carriage; a first correction process for correcting a transmission delay amount of the drive transmission means due to reversal of the carriage by increasing the amount by a predetermined amount; and after the first correction process, the moving direction of the carriage is reversed from a backspace direction to a space direction. When doing so, a second correction process is performed to offset the correction amount of the first correction process, and after the second correction process, the carriage is moved in the backspace direction by more than the first correction amount, and then moved in the space direction. A recording apparatus comprising: a control means for performing a third correction process to perform the third correction process. (2) having a detection means for detecting a reference position of the carriage, driving the pulse motor to move the carriage until the output of the detection means reaches an expected value, and then outputting the output of the detection means; 2. The recording apparatus according to claim 1, wherein the carriage is moved in a direction opposite to the moving direction until the value is reversed, and the amount of motor drive is used as the amount of transmission delay of the drive transmission means.