JPH0615907A - Printer - Google Patents

Abstract

PURPOSE:To provide a printer capable of avoiding deviation of printing position. CONSTITUTION:A linear encoder 11 storing information of printing position, a printer carriage 4 slidably supported and a pick-up device 10, which is mounted on the printer carriage 4 and reads the information stored in the linear encoder 11, are provided so that the printing position is controlled on the basis of the information read by the pick-up device 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer device, and more particularly to a printer device characterized in that the print position is controlled based on information about the print position.

[0002]

2. Description of the Related Art In FIG. 32, an optical sensor 3 provided on a carriage 1 slidably supported on a shaft 2 and a photo fence 4 extending parallel to the shaft 2 detect the position to correct the printing position. The device is shown. Further, in FIG. 33, the rotary encoder 6 installed on the rotary shaft 7 of the carriage driving motor 4 and the pickup element 5 detect the amount of rotation on the drive motor shaft to correct the printing position. A device for doing so is shown.

As another device for detecting a position, for example, Japanese Patent Publication No. 54-41335 discloses first and second current passages each having an anisotropic effect of magnetoresistance, which are repeatedly arranged close to these current passages. Approximately 1/2 (n + 1/2) λ for wavelength λ of magnetic signal
(n = 0,1,2 ...) and arranged so that the respective main current paths are substantially parallel to each other and one ends of the first and second current paths are connected to each other. A magnetoelectric conversion element is described, in which an output terminal is provided at a connection portion, and current supply terminals are provided at the other ends of the first and second current paths, respectively.

[0004]

In the device using the optical sensor, the detection resolution has a limit (about 90 DPI) and the alignment is performed at the timing of several times the print density. On the other hand, the correction was impossible, and the print position was misaligned.

Further, in a device using a rotary encoder, the vibration in the printing direction (movement in the x direction) in the carriage of the printer is affected by the drive transmission system between the motor drive shaft and the print head portion, and the carriage. Since it largely varies depending on the backlash of the support shaft, it is not possible to reliably correct the positional deviation on the printing paper surface caused by the positional deviation due to speed fluctuation or vibration.

An object of the present invention is to provide a printer device which can prevent the occurrence of printing position deviation.

[0007]

SUMMARY OF THE INVENTION The present invention is directed to a linear encoder for storing information relating to a printing position, a printer carriage slidably supported, and information stored in the linear encoder provided on the printer carriage. And a pickup element for reading, and the print position is controlled based on the information read by the pickup element.

[0008]

The pickup element provided on the printer carriage slidably supported reads the information stored in the linear encoder, and the printing position is controlled based on the information read by the pickup element. By determining the relative coordinates, the repetitive position accuracy can be improved, and high-speed / high-quality printing can be performed in bidirectional printing or multicolor matching printing in color printing.

[0009]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram for explaining a shaft having a linear encoder, FIG. 2 is a diagram for explaining print position control, and FIG.
FIG. 3 is a diagram illustrating one embodiment of a printer device.

1, 2 and 3, 1 is a printer device, 2 is a motor for driving the carriage 4, 3 is a belt for transmitting the driving force of the motor to the carriage 4, and 5 is a print head. , 6 has a linear encoder (magnetic memory) 11 having the same density as or higher than the printing density and storing absolute position information regarding printing, and a shaft extending parallel to the printing direction, and 7 parallel to the shaft. A slide shaft extending slidably to support the carriage 4 slidably, 8 a sintered oil-impregnated metal attached to the carriage 4, 9 a printer frame, 10 reading the absolute position information stored in the linear encoder 11. A pickup element (linear encoder element or MR head), 15 is an MR waveform processing for generating a position signal according to the absolute position information read by the pickup element 10. Circuit, 16 is MR waveform processing circuit 15
A control CPU 17 for receiving a position signal from the printer and generating a print timing signal is a pulley. The motor 4 for driving the carriage 4, the belt 3 for transmitting the driving force to the carriage 4 and the pulley 17 move the carriage 4, and the print head 5 prints on the print paper 19.

A linear encoder (magnetic memory) 11 installed parallel to the printing direction on the printing paper and storing position information is detected by a pickup element 10 installed near the print head 5 of the carriage 4. , Through the MR waveform processing circuit 15 to the control CPU 16.

The control CPU 16 synchronizes with this position signal,
The data necessary for printing is transferred to the print head 5 and a print timing signal is generated.

A waveform processing circuit is shown in FIG. The signal VI from the pickup element 17 is amplified by the amplifier 21 with the operating voltage P2 to obtain a signal P1 amplified to a processable voltage. Thereafter, the comparator 22 compares it with the reference voltage P3 to obtain a digital signal V0.

FIG. 4 shows a processing flow of the control CPU 16. In FIG. 4, after energizing the print head (4-1), it is judged based on the signal V0 from the MR waveform processing circuit 15 whether the movement corresponding to the print density is completed (4-).
2) The energization of the print head is started (4-3). After the preset energization time, a predetermined time is counted to energize the print head (4-4), and after the energization ends, the energization is cut off (4-5).

FIG. 6A shows the voltage VI input to the MR waveform processing circuit 15, FIG. 6B shows the voltage of the signal P1, and FIG. 6C shows the voltage V0 at the output end of the comparator 22. FIG.

FIG. 7 is an enlarged sectional view of the carriage 4, FIG.
Reference numeral 9 shows another slide shaft formed by the structure of the linear encoder itself.

Reference numeral 25 is a pickup element (linear encoder element) provided near the print head 5 of the carriage 4 for reading information stored in the linear encoder, and 26 is position information at a density equal to or higher than the print density. The stored linear encoder, 27 is a slide shaft installed in parallel with the printing direction, and 28 is a control circuit (not shown) via a relay board 29 provided in the carriage 4 for a signal from the linear encoder element 25. ) Is a lead line to be input to).

A groove is formed on the slide shaft 27 along the longitudinal axis thereof, that is, in the printing direction, and a linear encoder is attached to the groove by adhesion or fitting. In this case, the entire portion of the slide shaft 27 may be formed by the members forming the linear encoder.

Unlike the device described with reference to FIGS. 1 and 3, in this system, it is not necessary to provide a shaft having a linear encoder separately from the slide shaft, and a space dedicated to mounting the shaft having a linear encoder is unnecessary. This makes it easier to downsize the printer. Further, the cost can be reduced by reducing the number of parts, and especially when the linear encoder is attached to the groove, the material cost of the linear encoder can be further reduced. In this case, the slide shaft plays a role of a reinforcing material for the linear encoder, and apparently the rigidity of the linear encoder can be increased, and the problems of the positional accuracy deterioration due to the carriage sliding and the damage due to the strength deterioration are solved. I will get it.

In FIGS. 10 and 11, the linear encoder is formed by the structure itself, and the hollow structure reduces the weight and the material cost. Further, the outer diameter can be increased, and the linear encoder can be used. -The slide shaft 35 is shown, which can increase the rigidity of the frame and reduce the cost.

Unlike the slide shaft shown in FIGS. 7, 8 and 9, the slide shaft shown in FIGS. 10 and 11 has a hollow (so-called tubular) structure formed of the material forming the linear encoder as described above. So there is no linear encoder built into the groove seen in FIGS. Furthermore, there is also no shaft 6 with the linear encoder seen in FIG.

The materials in FIGS. 10 and 11 that are the same as those in FIGS. 7, 8 and 9 are denoted by the same reference numerals. In this modification, the operation of reading the information stored in the slide shaft 35 is the same as in FIG. 7.

Hollow slide shaft 3 formed of the material forming the linear encoder 26 shown in FIGS. 7 and 8 or the linear encoder shown in FIGS.
The information regarding the printing position is read from No. 5 by the hexagonal linear encoder element 25 installed on the carriage 4 (FIGS. 12 and 13), and modified examples of this linear encoder element are shown in FIGS.

The materials in FIG. 14 which are the same as those in FIGS. 7, 8 and 9 are denoted by the same reference numerals.

The carriage 4 is slidably attached to a slide shaft 27. The carriage 4 is provided with a cylindrical slide metal 37 in contact with the shaft 27, and a linear encoder 26 is provided in a groove formed in the shaft 27. Are attached by fitting or gluing. The slide metal 37 is composed of a linear encoder element for reading information on the printing position stored in the linear encoder 26.

FIGS. 15A and 15B show a cross section and a side surface of the slide metal. All parts of the slide metal 37 may be composed of a linear encoder element, but only a portion for reading information may be composed of a linear encoder element.

In this modified example, the relative position between the linear encoder 26 and the linear encoder element 37 is the linear encoder.
Since the accuracy is determined only by the accuracy of the encoder 26 and the linear encoder element 37, the relative positional accuracy can be more easily obtained. Further, since the linear encoder element and the slide metal can be shared, the number of parts can be reduced and the cost of the printer can be further reduced.

FIG. 16 is a view for explaining a cleaning ring, and FIGS. 17 (a) and 17 (b) are cross-sectional views and side views of the cleaning ring.

In the same figure, on the outside of the slide metal 37, there is a cleaner which is made of an elastic material and whose inside diameter is slightly small so as to fit to the outer surface of the slide shaft and which can remove ink, dust, dust and the like adhering to the outer surface of the slide shaft. -A ring 40 for each is mounted on the carriage 4 so as to be slidable with respect to the slide shaft.

In the initial state of use of the printer device, the relative position between the linear encoder element and the linear encoder attached to the slide shaft is stable, but as time passes, the above-mentioned dust adheres to dust and the like. Therefore, the relative position becomes distant and the control of the printing position becomes unstable. When the distance between the linear encoder element and the linear encoder becomes long, the signal reading from the linear encoder becomes more unstable than in the initial state. However, by installing this cleaning ring, the linear encoder element It is possible to prevent dust and the like from entering the gap between the linear encoder and the linear encoder, maintain the relative position in the initial state, and prevent deterioration of the reading accuracy of the magnetic information stored in the linear encoder.

In a printer device provided with a linear encoder for detecting only the print position, the one line full print width carriage must always move when the carriage position is not detected.

FIG. 29 is a cross-sectional view showing a linear encoder and one linear encoder element that stores only information relating to the printing position.

In FIG. 29, 45 is a linear encoder element, 46 is a slide metal, and 47 is a linear encoder.
Da, 48 is a part where information about the print position is stored, 4
Reference numeral 9 is a signal output terminal, and 50 is a lead wire.

When only the information on the print position is stored in the linear encoder 47, when the printing is completed in the middle of one line and the carriage is stopped at the end position, slight vibration of the stationary state occurs. The timing signal may be picked up and the correct carriage position may not be detected.

Therefore, in order to perform the shortest distance printing, a signal detecting means for separately detecting the carriage position is provided (for example, as shown in FIG. 27, a shaft 42 having a linear encoder for detecting the printing position, In addition to the linear encoder element 43 for detecting the printing position, a photo-interplater 44 provided on a carriage 46 supported by a shaft 45 transmits a signal indicating a carriage position where a light-shielding portion is periodically formed on a transparent sheet. It is necessary to detect and control the printing operation of the printer), which requires an extra space and is expensive.

Therefore, two phases of a print timing signal and a signal having a relatively wider interval than the print timing signal for detecting the position of the carriage are recorded (stored) on one linear encoder, and the two phases are recorded. Since the carriage position can always be detected by detecting both by the linear encoder element, an extra space is not required, and the shortest distance printing according to the printing data can be performed at low cost.

FIG. 18 is a sectional view showing an example of a linear encoder that stores two phases of a print timing signal and a signal with a relatively wide interval for detecting the position of the carriage.
In FIG. 18, the same numbers are used for the same materials as in FIG. 29. 52 is a signal output terminal, 51 is a lead wire,
53 is a linear encoder element for detecting the carriage position,
56 is a part in which information about the carriage position is stored,
Reference numeral 54 is a slide ring, and 55 is a linear encoder.

The part 48 and the part 56 have an angle (see FIG. 18).
About 90 degrees) apart, each linear encoder element 4
5, 53 detects the respective information.

FIG. 19 shows the signal waveforms relating to the information respectively detected by the two linear encoder elements and the positional relationship between the carriage and the linear encoder.
Is a print position detecting linear encoder element, 53 is a carriage position detecting linear encoder element, 61 is a carriage, and 68 is a shaft provided with a print position detecting linear encoder and a print position detecting linear encoder.

FIG. 19 is based on the flowchart of FIG.
The movement operation of the carriage will be described.

In response to the print position detection signal (hereinafter referred to as A signal) from the home position 62 in the direction of the arrow (printing direction), the origin of the rising of the carriage position detection signal (hereinafter referred to as B signal) is set by the carriage 61. To start printing (20-
1) When the printing is completed at the position 65 (20-2), the carriage 61 does not stop at the position 65 and moves in the printing direction as it is (20-3), and the next rising edge of the B signal at the position 66 is detected. After (20-4), after moving a predetermined distance (20-5), it returns to position 62 and stops (20-
6) The printing is started from the position 62 of the next line (when the next line is printed from the position 62). Here, the predetermined distance means a sufficient distance that the B signal does not fluctuate even if the carriage 61 stops and a slight vibration occurs in the stopped state.

If the print start position of the next line is not position 62 but position 63, the carriage 61 returns from position 66 (20-7) and the rising edge of the B signal at position 64 is detected. (20-8) After counting a predetermined number of A signal pulses and confirming a predetermined number of pulses, (20-1)
0), stop at position 63, start printing from position 63 (20-11), and finish predetermined printing (20-1).
2).

In this way, the print start and end positions are set to B
Since it is determined from the relationship between the number of signal pulses and the number of A signal pulses, the printing distance can be minimized according to the printing data. In this way, two phases of the print timing signal and the signal having a relatively wider interval than the print timing signal for detecting the carriage are stored on one linear encoder, and the linear encoder element for two phases is stored. Since the carriage position can always be detected by detecting each signal of the two layers, the shortest distance printing according to the printing data can be performed at a low cost without taking an extra space.

FIG. 30 shows a general printer equipped with an origin detection switch, and FIG. 31 is an enlarged view of the origin detection switch.

In FIG. 30, 80 is a print timing sensor, 81 is an origin detection switch, 82 is a carriage, 83 is a printer frame, 84 is a motor for driving the carriage 82 via a belt 85, Reference numeral 86 is a shaft that supports the carriage 82, and 87 is a photo fence that causes the sensor 80 to detect the print timing.

According to this apparatus, a switch for detecting the origin is required in addition to the means for detecting the print signal, and the number of parts is increased. In addition, the position adjustment is required for the variation of the switch 81 fixed to the screw 88 in FIG. That is also a factor of cost increase.

Further, the step-out method of the pulse motor is not only accompanied by vibration and noise at the time of step-out, but also requires physical strength and the position accuracy is not good. FIG. 21 is a diagram illustrating a device for detecting the origin of the printer device.
Reference numeral 0 is a linear encoder, 91 is a linear encoder element provided on a carriage (not shown), and 92 is a lead wire.

FIG. 22 shows the output signal waveform of the linear encoder element 91 during the operation of the apparatus shown in FIG. 21, and FIG. 23 shows the operation flow chart of the apparatus.

In FIG. 21, the linear encoder 90 has unmagnetized portions (no signal portions) at both ends.

When the carriage moves in the direction A (origin direction), that is, when the linear encoder element 91 moves in the direction A (FIGS. 23 and 23-1), the print timing signal stored in the linear encoder 90 is sent to the carriage. The linear encoder element 91 provided provides detection as shown in FIG.

When the carriage continues to move in the direction A, the linear encoder element 91 enters the non-magnetized portion (no signal portion) of the linear encoder (FIGS. 23 and 23-2), and the linear encoder element 91 moves. If it is located in the non-magnetized portion, no timing signal is detected and it moves for a predetermined distance (see FIGS. 23 and 2).
3-3). If that state continues for a certain period of time, the carriage stops for a moment and then moves in the B direction (see FIGS. 23 and 2).
3-4).

Next, when the linear encoder element 91 reaches the print signal storage portion of the linear encoder, signal output starts. It is determined whether or not the first timing signal rises in this B-direction movement (FIGS. 23 and 23-5).
By setting the position 95 (FIG. 22) as the origin (home position), the print start position is set (FIG. 23, 23-6), and correct printing can be performed without positional deviation.

Both ends of the linear encoder may be magnetized parts instead of the non-magnetized parts. In this case, the signal detected from the magnetized parts has a flat signal waveform different from the timing signal. Configured to be a signal that has,
It suffices if it can be distinguished from the first timing signal. FIG. 28 is a diagram for explaining the printing operation of the print nozzle of a general device.

In FIG. 28, the print nozzle 100 provided on the print head moves from the point A while moving in the direction of the arrow Z (printing direction) to detect the constant value at the point B, and at the point C, the ink at the speed of Vi. Suppose that it has been ejected. The speeds of the print nozzles 100 at this time are standard V, low speed Va, and high speed V, respectively.
If b, the paper surface 10 of the ink ejected at each speed
The arrival points at 4 are Pa, which are indicated by dotted arrows,
P and Pb.

Even if the absolute position of the print position is detected in this way, if the speed of the print nozzle 100 at that time is different, P
As a, P, and Pb, the print positions are different.

The above-mentioned optical sensor and rotary encoder
In order to solve the drawbacks of the printing method, the ejection of ink may be changed according to the speed of the print head.

In FIGS. 25 and 26, the speed is obtained from the time difference between the position A point information and the position B information, and if the speed is lower than the standard speed, the vehicle moves forward from point C by a.
By ejecting ink at the point C'and retreating by b at high speed, by ejecting the ink at the point-C ', it is possible to constantly reach the standard position P even if the speed changes, and high-quality printing is possible. Will be obtained.

Next, the processing flow will be described based on the flow chart of FIG.

In FIG. 24, the control circuit is point A.
The timer value TA when passing (FIGS. 25 and 26) is held (stored) (24-1), and the point B (FIGS. 25 and 2) is held.
The timer value TB when passing 6) is held (stored) (24-2), the difference (TB-TA) between the two, that is, the moving speed TX is obtained from the moving time (24-3), and the standard speed T
The velocity error ΔT from P is calculated (24-4), the correction table is quoted to calculate the ink ejection position correction value m for ΔT (24-5), and the standard ink ejection position C is set to the correction value m. The optimum ink ejection position + C 'or -C' is calculated by addition (2
4-6).

[0061]

The pickup element provided on the printer carriage slidably supported reads the information stored in the linear encoder, and the printing position is controlled based on the information read by the pickup element. By determining the relative coordinates regarding the position, it is possible to improve the repetitive position accuracy, and it is possible to perform high-speed / high-quality printing in multicolor matching printing in bidirectional printing or color printing.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a shaft provided with a linear encoder.

FIG. 2 is a diagram illustrating print position control.

FIG. 3 is a schematic view of an embodiment of the printer device of the present invention.

FIG. 4 is a flowchart showing the operation of the control CPU.

FIG. 5 is a diagram showing a waveform processing circuit.

6 is a graph showing the voltage of each part of the waveform processing circuit of FIG.

FIG. 7 is an enlarged cross-sectional view of a carriage.

FIG. 8 is a schematic cross-sectional view of a slide shaft and a linear encoder element.

FIG. 9 is a diagram showing a slide shaft.

FIG. 10 is an enlarged cross-sectional view of another carriage.

FIG. 11 is a view showing another slide shaft.

FIG. 12 is a diagram illustrating a modified example of the linear encoder.

13 is a schematic sectional view of the linear encoder of FIG.

FIG. 14 is a diagram illustrating another modification of the linear encoder.

FIG. 15 is a diagram showing a slide metal.

FIG. 16 is a diagram illustrating a cleaning ring.

FIG. 17 is a diagram illustrating the shape of a cleaning ring.

FIG. 18 is a diagram illustrating a linear encoder that stores two-phase signals.

FIG. 19 is a diagram illustrating detected signal waveforms.

FIG. 20 is a flowchart for explaining the movement operation of the carriage.

FIG. 21 is a diagram illustrating an apparatus for detecting the origin of the printer apparatus.

22 is a diagram showing an output waveform from the linear encoder when the device of FIG. 21 is in operation.

23 is a flowchart for explaining the operation of the apparatus shown in FIG.
It is

FIG. 24 is a flowchart illustrating another operation of the control CPU.

FIG. 25 is a diagram illustrating ink ejection positions according to an embodiment of the printer device of the present invention.

FIG. 26 is a diagram illustrating another ink ejection position according to the embodiment of the printer device of the present invention.

FIG. 27 is a diagram showing a general printer apparatus having a shaft having a linear encoder for detecting a print position and another shaft having a linear encoder for detecting a carriage position.

FIG. 28 is a diagram illustrating ink ejection positions of a general printer device.

FIG. 29 is a schematic sectional view of a shaft provided with a linear encoder that stores information only for printing position detection.

FIG. 30 is a diagram showing a printer device having a switch for origin detection.

31 is an enlarged view of a switch of the apparatus of FIG. 30.

FIG. 32 is a diagram showing a printer device including an optical sensor.

FIG. 33 is a diagram showing a printer device provided with a rotary encoder.

[Explanation of symbols]

 1 Printer Device 2 Motor 3 Belt 4 Carriage 5 Print Head 6 Linear Encoder 7 Slide Shaft 10 Linear Encoder Element 11 Linear Encoder

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kozo Yamaguchi 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Prefecture

Claims (9)

[Claims] 1. A linear encoder for storing information about a printing position, a printer carriage slidably supported, and a pickup element provided on the printer carriage for reading information stored in the linear encoder. And a printer device configured to control a print position based on information read by a pickup element. 2. The linear encoder is provided on a shaft supported so as to extend in the printing direction, the printer carriage is supported on a slide shaft extending parallel to the shaft, and the pickup element is provided. The printer device according to claim 1, wherein the printer device is configured to be slidable along the shaft. 3. The printer apparatus according to claim 1, wherein the printer carriage extends in the printing direction and is supported by a slide shaft having a linear encoder. 4. The printer device according to claim 3, wherein the slide shaft has a hollow structure. 5. The printer device according to claim 3, wherein the pickup element has a through hole, and the slide shaft penetrates the through hole. 6. A cleaning member mounted on the printer carriage so as to be in contact with the surface of the slide shaft is provided at at least one end of the pickup element in the printing direction. The printer device according to 1. 7. A linear encoder provided on the slide shaft stores information indicating a printing timing interval and information for detecting the position of the carriage,
4. The printer device according to claim 3, wherein the pickup element includes a first element for reading information indicating a print timing interval and a second element for reading information for detecting the position of the carriage. 8. The pickup element reads information indicating a print timing interval from the linear encoder, and sets print timing based on information stored in a leading edge portion of the stored information with respect to a print direction. The printer device according to claim 2, wherein the printer device is configured as described above. 9. The pick-up element is provided with a print head for ejecting ink, and the print head sets the ink ejection position in correspondence with the sliding speed of the pickup element so as to set the printing position to a predetermined position. 9. The printer device according to claim 1, wherein the printer device is configured to perform.