JPH0365364A - Printing device - Google Patents

Abstract

PURPOSE:To permit high-quality printing without any deviation of printing with a low cost by a method wherein the change of end positions is detected by end position sensors, provided at left-and-right ends, while the printing is started after a predetermined period of time from the point of variation. CONSTITUTION:Left-and-right end positions are detected by two sets of end position detecting means 24, 26, detecting the end positions when a printing head 21 is moved into left-and-right, while printing is started after predetermined periods of times T, T' counted by a timer means 44 from the point of variations of end position signals 36, outputted upon detecting the end positions. Accordingly, step control is not effected whereby the error of one step will never be generated. On the other hand, home positions 38, 39 are set by a home position setting means 27 at positions whereat the speed of the printing head 21 becomes constant at the point of variation of the end positions whereby there may be no affection even when the printing head is moved slightly from the home positions 38, 39 by external force. As a result, the deviation of starting positions will never be generated. Further, two sets of end position detecting means 24, 26 are provided and the printing is effected by reciprocating operation whereby deviation between normal and reverse printings will never be generated and a high-quality printing may be effected.

Description

[Detailed Description of the Invention] [Summary] An object of the present invention is to provide a printing device which performs printing by reciprocating left and right movement of a print head, and which is capable of performing high-quality printing at a low price and without printing misalignment. In a printing device that performs printing by driving an actuator in response to a through-up instruction or a through-down instruction from a control means and reciprocating a print head from side to side, a pair of end position detection means for detecting left and right end positions; A home position setting means for setting a home position at a position where the print head reaches a constant speed at the change point of the end position, and a time for starting a pin fire operation for printing operation after a predetermined time from the change point of the end position. a timer means for setting;
It was constructed by

[Industrial Field of Application] The present invention relates to a printing device that performs printing by reciprocating left and right movements of a print head.

Recent printing devices are required to be low-cost and capable of high-quality printing. Therefore, it is necessary to prevent the embossing position shift and forward/reverse printing shift by eliminating variations in printing operation control.

[Problems to be Solved by the Prior Art and the Invention] As a conventional printing device, there is one that uses, for example, an end position sensor and a slit disk to perform high quality printing.

In this printing device, a shaft is driven by a step motor via a belt, and a slit 1 for dot pulses and a slit for zone pulses are installed at one end of the shaft, which moves the print head left and right along with the carriage, as shown in Figure 4. The slit disk 3 on which the slit disk 2 is formed is fixed so that the movements of the slit disk 3 and the carriage are completely synchronized.

4 is an end position signal obtained by amplifying the detection signal of the end position sensor 5, which detects that the print head is at the end, by an amplifier 6, and 7 is detected from the zone pulse slit 2 of the slit disk 3 by a photointerrupter 8'. death,
The zone pulse amplified by the amplifier 9 is detected by the photointerrupter 8 from the dot pulse slit 1 of the slit disk 3, and the dot pulse 10 is amplified by the amplifier 9.

The change point ■ of end position signal 4 is zone pulse 7
It is adjusted to change in the order of [existence] God ■ groaning ■ approximately in the center of ■ and ■, and printing starts at the position of ■. Therefore, FIG. 5(A).

As shown by ■, ■, and ■ in (B), even if there are variations in the change points of the end position signal 4, the movement of the slit disk 3 and the carriage are connected by the shaft as described above, so Since they are synchronized, the print position is accurate. That is, as described above, the printing position will not shift as long as the change of ■God■God■ is not disrupted.

However, although this printing device can obtain high quality printing, it requires a slit disk 3 and a circuit 9 for processing signals obtained from the slits 1 and 2.
There are problems in that the process becomes complicated and costly.

Next, as another conventional example, as shown in FIG. 6, a pulse motor 12 is driven by a drive circuit 11, and a wire 13 is
The print head 14 is controlled via the printer to print on the paper surface 15, and the end position is detected by 11 end positions 16 (7), and is amplified by an amplifier 17.

This printing device achieves cost reduction by sacrificing print quality to some extent, and uses one end position sensor.
6, the print head 14 is controlled by the pulse motor 12.

In this printing apparatus, first, as shown in FIG. 7, the print head 14 is positioned by a predetermined command, power is turned on, etc., and this position is set as a home position 18. In other words, from the change point of end position signal 4 to
The step number is set as home position 18. Then, as shown in FIG. 8, printing is started from this home position 18 in a predetermined number of steps.

However, this printing device does not require the slit disk 3 or the signal processing circuit 8°9 as described above, so it is inexpensive. In this case, the printing operation will be performed in a misaligned state.

Furthermore, even if the home position 18 is positioned many times, as shown in FIG.
When the fourth step is set to the home position 18, the stopping position error is sometimes ``■'' and sometimes ``■'', and an error of one step occurs. Therefore, no forward/reverse deviation occurs, but a deviation in the ejecting position does occur.

Furthermore, as shown in FIG. 10, there is a method of controlling printing so that it starts after a predetermined time T from the change point of the end position signal 4, regardless of the number of steps. Since there is only one position sensor, when performing return printing, it is necessary to rely on step management to move the print head from the stop position to the start of return printing. Since there is a maximum error of one step between the completed position and the position where return printing is started, forward/reverse printing deviation occurs. That is, in the conventional printing device, as shown in FIG.
There was a problem in that the embossing position shift as shown by C in B) or the forward/reverse printing shift as shown in D in FIG.

The present invention has been made in view of these conventional problems, and an object of the present invention is to provide a printing device that is inexpensive and capable of performing high-quality printing without misprinting.

[Means to solve the problem] FIGS. 1A and 1B are diagrams explaining the principle of the present invention.

In FIG. 1(A), reference numeral 21 denotes a print head that performs left and right reciprocating motion by driving an actuator 22 in accordance with a through-up instruction or through-down instruction from a control means 30;
5.26 is a pair of end position detection means for detecting the left and right end positions; 27 is a home position setting means for setting a home position 38, 39 at a position where the print head 21 has a constant speed at a change point of the end position; , 44 is a timer means for setting a time for starting a pin-fire operation for a printing operation after a predetermined time T, T' from the point of change of the end position.

[Function] In FIGS. 1A and 1B, the end position 2, which is the end when the print head 21 moves left and right, is detected.
The left and right end positions are detected by the two end position detection means 24 and 26, and printing is started after a predetermined time T, T" measured by the timer means 44 from the change point of the detected end position signals 36 and 37. Therefore, Since conventional step management is not performed, a one-step error that occurs when printing with step management does not occur.Furthermore, at the change point of the end position, the home position is set at a position where the print head 21 has a constant speed. Since the home position 38.39 is set by means 27, the print head is moved to the home position 38.39 by external force.
Even if it moves a little from there, it will have no effect. As a result, there is no occurrence of deviation in the ejection position, and since the two end position detection means 24 and 26 are provided and printing is performed in a reciprocating manner as described above, there is no possibility of deviation in forward/reverse printing. Since there is no paper, high-quality printing can be performed.

Furthermore, since a slit disk or a complicated signal processing circuit is not required, costs can be reduced.

[Example] Embodiments of the present invention will be described below based on the drawings.

FIGS. 2 and 3 are diagrams showing one embodiment of the present invention.

First, to explain the configuration, in FIG. 2, 21 is a print head that is integrated with a carriage (not shown). Makes a reciprocating motion. 24 is a left end position sensor (end position detection means), and the left end position sensor 24 detects the left end position of the print head 21 via a shielding plate 25. That is, the left end position sensor 24 detects the left end of the reciprocating movement of the print head 21, and the detection range is the distance at which the left end position sensor 24 does not detect the shielding plate 25 when through-up is completed when moving from left to right. . Reference numeral 26 denotes a right end position sensor (hot water end step detection means), which detects the right end position of the print head 21 via the shielding plate 25. That is, the right end position sensor 2G detects the right end of the reciprocating movement of the print head 21]7, and the detection range is a distance that allows through-down.

Here, the distance between the end positions 3 must be adjusted in advance in the printer, or mechanical errors in the distance can be adjusted using the timer circuit 44.
A fixed interval ε is obtained by correcting the predetermined times T and T' measured at .

The pulse motor 22 is driven by a drive circuit 29 into which motor control pulses 28 from a pulse motor control circuit 27 are input. The pulse motor control circuit 27 has a control section 30 (
Through-up instruction from control means) 31. Or according to the through-up table 33 or the through-down table 34 according to the through-down instruction 32, the pulse generation circuit 35
is used to generate the motor control pulse 28. The pulse motor control circuit 27 also has a function as a home position setting means, and receives left and right end position signals 36.3 from left and right end position sensors 2.4.26.
At each change point 7, home positions 38 and 39 are set at the left and right positions where the speed of the print head 21 becomes constant.

That is, the left home position 38 is the print head 21
Set the position so that even if the signal passes through from the left to the right and completes the through-up, it will not pass through the change point of the left end position signal 36 [7]. In addition, the right home position 39 passes through the change point of the right end position signal 37 before the print head 21 moves from left to right and goes through down (
7). Through-up and through-down are predetermined acceleration and deceleration of the pulse motor 22, and start and end while the end position signals 36 and 37 are being detected.

The output of the left end position sensor 24 is sent to the amplifier 4.
0 as the left end position signal 36, and the output of the right end position sensor 26 is amplified by the amplifier 4.
], and are input to the change point detection circuit 42 as the right end position signal 39, respectively. The change point detection circuit 42 detects the change points of the left and right end position signals 36 and 37, and detects the change point signal 4 from on to off.
3 is output to the timer circuit (timer means) 44, and a change point signal 45 from OFF to ON is output to the control section 30. The timer circuit 44 receives the change point signal 43 for a predetermined period of time T, T-.
Afterwards, a time-up signal 46 is output to the head pin control circuit 47. Here, the predetermined time T is the positive direction (left → right)
In the printing operation, this is the time from the point of change of the left end position signal 3G until printing the leftmost dot row for one character.

The time T- is the time from the change point of the right end position signal 37 to printing the right end 1-column driver I column of the final character in the printing operation in the reverse direction.

These predetermined times T and T' can be predetermined fixed times because the rotational speed of the pulse motor 22 can be determined.

The head pin control circuit 47 prints the pin control pulse 48 by human power of the time-up signal 46.
9, the print head 21- is driven by the Radbin drive circuit 49 to perform a pinfire operation, and prints on the paper 51 via the ribbon 50.

Note that 52 is a host combination J that gives instructions to the control unit 30.
, -It is evening.

Next, the operation will be explained.

In response to instructions from the host computer 52, the control section 30 converts the print data into an image pattern to the head pin control circuit 47 to the head pin control circuit 47, and when an instruction to start printing is received,
A through-up instruction 31 is given to the pulse motor control circuit 27. The pulse motor control circuit 27 applies the motor control pulse 28 to the drive circuit 29 using the pulse generation circuit 35 according to the through-up table 33, and drives the pulse motor 22 (see FIG. 3(E)).

This causes the print head 21 to through-up, but the through-up is completed while the left end position signal 36 is at the 1" level (see No. 31M (D)). The print head 21 passes through the left end position sensor 24. When,
The left end position signal 36 becomes "O" level, and the change point detection circuit 42 detects this and starts the timer circuit 44 using the change point signal 43 as a trigger (see FIG. 4 (A).
).

(C), see).

The timer circuit 44 performs a timer operation, and when the time is up, outputs a time-up signal 46 to the head pin control circuit 47 (FIG. 4(F)).

(G), see). The head pin control circuit 47 outputs a pin control pulse 48 to the print rad pin drive circuit 49 based on the image pattern to instruct head pin fire, and thereby the print head 21 fires the paper 51 via the ribbon 50.
(See Figure 4 (H)). Here, the head pin fire only needs to operate at a constant cycle. This is because the print head 21 is moved at a constant speed by the pulse motor 22.

Next, the right end position sensor 26
When the passage of the right end position signal 37 is detected, the change point detection circuit 42 detects the change point of the right end position signal 37, and based on the change point signal 45, the control circuit 30 issues a through-down instruction 32 to the pulse motor control circuit 27, and the pulse motor 22 (see FIGS. 4(B) to 4(F)). and,
The position after completion of the through-down is the right home position 39.

Note that the printing operation from right to left is also the same as described above except for the time axis until the start of printing.

In this way, a one-step error does not occur, unlike when printing with conventional step management. Further, even if the print head 21 is moved by an external force when the print head 21 is located at the home position 38, 39, there is no effect. That is, since no forward/reverse printing deviation or embossing position deviation occurs, high-quality printing can be performed.

Furthermore, since a slit disk is not required and a complicated signal processing circuit is not required, the cost is low.

[Effects of the Invention] As explained above, changes in the end position are detected by the end position sensors provided on the left and right sides, and printing is started a predetermined time after the point of change. Misalignment can be prevented and high quality printing can be performed. Furthermore, since a slit disk or the like is not required, costs can be reduced.

[Brief explanation of drawings]

Figures 1 (A) and (B) are diagrams explaining the principle of the present invention;
The figure is a block diagram showing an embodiment of the present invention, Figure 3 is a timing chart, Figure 4 is an explanatory diagram of the conventional example, and Figures 5 (A) and (B) show the end position signal due to changes in through-up. FIG. 6 is an explanatory diagram of another conventional example. FIG. 7 is an explanatory diagram of the home position. FIG. 8 is an explanatory diagram of printing operation. FIG. 9 is an explanatory diagram of step error. FIGS. 11A and 11B are explanatory diagrams of other printing operations. In the figure, 21...Print head, 22...Pulse motor (actuator), 23...
・Wire, 24... Left end position sensor (end position detection means), 25... Shielding plate, 26... Right end position sensor (end position detection means), 27... Pulse motor control circuit (home position setting means), 8...Motor control pulse, 9...Drive circuit, 0...Control unit (control means), 1...Through-up instruction, 2...Through-down instruction, 3...・Through-up table, 4...Through-down table, 5...Pulse generation circuit, 6...Left end position signal, 7...Right end position signal, 38...Left home position, 39...・Right home position, 40. 41... Amplifier, 42... Changing point detection circuit, 43. 45... Changing point signal, 44... Timer circuit (timer means) 46... Time up signal, 47 ... Head pin control circuit, 48 ... Pin control pulse, 49 ... Radbin drive circuit for printing, 50 ... Ribbon, 51 ... Paper, 52 ... Host computer. Home Pojinyon's Zhanguangming area/No. Figure 10

Claims (1)

[Claims] In a printing device that performs printing by driving an actuator (22) in response to a through-up instruction or a through-down instruction from a control means (30) and reciprocating the print head (21) from side to side, a pair of left and right end positions are detected. end position detection means (24), (26), and the print head (21) at a change point of the end position;
) is at a constant speed, home position (38),
(39) Home position setting means (27) for setting
and a predetermined time T, T from the change point of the end position.
1. A printing device characterized by comprising: timer means (44) for setting a time for starting a pinfire operation for printing after '.