JPS6072746A - Character size varying printer - Google Patents

Abstract

PURPOSE:To obtain various kinds of character sizes with the same recording head by tilting the recording head by several stages. CONSTITUTION:A recording head 6 is mounted rotatably on a recording head holder with a pin 8 in the direction of moving the carriage. Another pin 9 fixed on the recording head 6 is linked to a slide lever 13 mounted slidably on the carriage 4 in the direction of the arrow. By moving a knob 14 of the slide lever 13, the angles alpha of tilting of the recording head 6 are selected by several stages to change the character height. When the length of a heat generating element train 20 is represented by (d), the character height l=dcosalpha. Then, the carriage 4 is driven at the speed ratio of V/Vo=(dcosalpha+R)/(d+r) with a carriage speed control function block to obtain the character width (b) corresponding to the character height l. Where, Vo is the carriage speed when the angle of tilting is 0 and (r) represents space between characters.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an improvement in a variable character size printing device, and more specifically, to an improvement in a variable character size printing device.
This invention relates to a printing device in which character size can be varied by tilting the same recording head.

<Technical background of the invention and its problems> In a printing device equipped with a recording head having a row of printing elements, a conventional method for making the character size variable is, for example, preparing multiple types of recording heads according to each character size. There is a known device in which the device is kept in place and then replaced as appropriate.

For example, FIG. 1 shows an example in which changing the character size by replacing the recording head is applied to a thermal transfer serial printer.

FIG. 1 is a perspective view showing the structure of a conventional thermal transfer serial printer with variable character size using an exchangeable recording head.
FIG. 2 is a perspective view showing a conventional recording head attachment/detachment mechanism disclosed in, for example, Japanese Patent Laid-Open No. 56-154071 and Japanese Patent Laid-Open No. 55-158971.

In Figure 1, I is recording paper (plain paper), 2 is the recording paper (plain paper), and 2 is the recording paper (plain paper).
A platen (3) is a pair of guide shafts provided parallel to the platen (2), and a platen (4) is suspended from the pair of guide shafts (3). The carriage 5 is a timing belt or wire, and the carriage 5 is reciprocated by a driving device (not shown) via the timing belt or wire 5.

Reference numeral 6 denotes a removable recording head (thermal head) mounted on the carriage 4, in which a plurality of heating elements are provided at predetermined intervals, and by selectively energizing each heating element, Joule heating is generated. The meltable ink applied to the thermal transfer ink ribbon is melted and transferred onto plain paper 1 to represent characters, figures, etc. 10 is an ink ribbon supply section, and 11 is an ink ribbon winding section. A thin ink ribbon 12 is guided between the plain paper 1 and the recording head 6.

When the carriage 4 moves forward, the recording head 6 is urged toward the platen 2 by a spring (not shown), and thermal transfer recording is performed while being pressed against the platen 2 via the ink ribbon 12 and the recording paper 1. .

The used ink ribbon 12 after recording is wound up by the recorded length of the row by an ink ribbon winding device (not shown) when the carriage returns (during backward movement). Therefore, during the carriage turn, the recording head 6 is separated from the platen 2 by a recording head lift device (not shown).

In the conventional serial printing type thermal transfer recording apparatus (ink ribbon stationary type) configured as described above, when changing the character size, the recording head 6 is first pulled out from the recording head holder 7 (see FIG. 2). Next, another recording head 6 having a different heating element size and pitch is attached.

The recording head 6 is equipped with a character size detection terminal in addition to a common terminal for each heating element and each signal terminal. Thereby, the character size of the attached recording head 6 is detected, and the carriage 4 is moved forward at a carriage movement speed corresponding to each character size to perform recording. That is, the vertical length of a character is determined by the pitch of each heating element of the recording head 6, and the horizontal length of a character is determined by the carriage movement speed.

However, in conventional devices of this kind, the recording head 6 is different for each character size, so it is necessary to prepare a variety of expensive recording heads 6, and replacing the recording head 6 is troublesome, so care must be taken when handling. There were some problems, such as:

<Object of the Invention> An object of the present invention is to eliminate the above-mentioned drawbacks and provide a variable character size printing device that enables recording of various character sizes using the same recording head without replacing the recording head. In order to achieve this objective, the present invention reciprocates a carriage equipped with a recording head having an array of printing elements parallel to the platen and perpendicular to the paper feeding direction, and prints on the recording paper using the recording head. The printing device includes angle switching means for tilting the recording head in several stages to tilt the printing element array, and the operation timing of each printing element is changed in accordance with each inclination angle to produce character sizes in several stages. It is configured to allow selection.

<Embodiments of the Invention> Hereinafter, an example in which the present invention is applied to a thermal transfer serial printer will be described in detail with reference to the drawings.

FIG. 3 is a partial perspective view showing the configuration of a variable character size thermal transfer serial printer embodying the present invention, and the same parts as in FIG. 1 are designated by the same reference numerals.

In FIG. 3, reference numeral I indicates recording paper (plain paper); 2 indicates a platen that also serves as a paper feed roller that wraps the recording paper (plain paper) 1 and is intermittently rotated by a line feed means (not shown); 3;
A pair of guide shafts 4 provided parallel to the platen 2
6 is a carriage suspended on the pair of guide shafts 3 so as to be able to reciprocate; 6 is a recording head mounted on the carriage 4;
1''i recording head holder.

This device also has a manual knob 14 and a character size scale 15.
The recording head inclination angle switching device has a recording head inclination angle switching device as described below, and further includes a drive device (not shown) for reciprocating the carriage 4 and an ink ribbon feeding device.

The recording head 6 is provided with a variable inclination angle, and is configured so that the inclination angle, ie, the character height, can be manually selected in several steps.

Next, this inclination angle switching device will be explained with reference to FIGS. 4(a) and 4(b).

FIGS. 4(a) and 4(b) are diagrams showing the configuration of a recording head inclination angle switching device of the present invention, respectively.

In the figure, six recording heads are inserted into the recording head holder 7, and the first pin 8 connects the recording head holder 7.
It is rotatably attached to the carriage in the direction of carriage movement.

The first pin 8 is placed as close as possible to the heating element row 20 (FIG. 5). Since this rotates using the first pin 8 as a fulcrum, when the recording head 6 is tilted as shown in FIG. 5, the heating element array 20 moves away from the initial position by a distance Δy.

If this Δy is too thick, the platen 2 and the heating element array 20
This is because the positions of the images do not correspond and transfer recording becomes impossible.

Further, another second pin 9 is fixed to the recording head 6 at a position apart from the heating element array 20, and this second pin 9 is slidable in parallel to the moving direction of the carriage 4. It is connected to a slide lever 13 attached to the carriage 4.

Therefore, by manually moving the knob 14 of this slide lever 13, the oblique angle of the recording head 60 can be changed. Further, a click mechanism (not shown) is added to the slide lever I3 so that the inclination angle of the recording head 6 can be set in several stages instead of being changed continuously. This click mechanism also serves as a simple locking function for the recording head 6.

By moving the knob 14 (z) of the slide lever 13, the inclination angle of the recording head 6 is selected, thereby changing the character height. In other words, as shown in FIG.
In the case of 0°, if the standard character height when the inclination angle is 0°, that is, the length kd of the heating element row 20, then the character height l 14
l ” d ccsα.

For example, if the standard character height is 12 points, by selecting the tilt angles shown in the table below, character heights of 12 points to 9 points can be obtained.

(Note: 1 point = 0.3514 points) Note that due to the inclination of the recording head 6, there is a gap between the first heating element 21 and the Nth heating element 22 in the moving direction of the carriage 4, that is, in the figure. Distance also in the X direction x = d
qinα is generated. Therefore, if printing is performed at the same application timing as when the inclination angle is 0°, the printed result will also be skewed. In order to correct this, an application timing control function, which will be explained later, is required. Furthermore, as the character height l is changed, the character width also needs to be changed, and there are two methods for this correction, as will be described later. In addition, positional deviation correction (X direction, Y direction) is also required. In order to perform all of these corrections, it is necessary to recognize the current tilt angle of the recording head 6.

Therefore, this device is equipped with a sensor 16 that detects the inclination angle of the recording head 6, that is, the slide lever 18 device.
An example thereof is shown in FIG.

The sensor 16 is not mounted on the carriage 4, but two photosensors I6 are installed on the chassis +7 of this device.

Therefore, while the carriage 4 is stopped at the home position, the slide lever tA is detected by the output of the two photosensors 16, and only while the ridge 4 is stopped.
The position of the slide lever 13 may be detected. A reflective plate 18 is attached to the slide lever 13 in 1 and 2.
The four photosensors 16 can detect the four states of inclination of the recording head 6 shown in FIGS. By increasing the number of photo sensors 16, even more types of character sizes can be set.

As another method for detecting the inclination angle of the recording head 6, the inclination angle of the recording head 6 may be recognized by directly incorporating a slide switch mechanism (not shown) into the slide lever 13 on the carriage 4. good. In this case, in order to extract signals from the moving carriage 4, it is necessary to connect the signal line of the slide switch to a sliding cable, etc. together with the signal line to each heating element 20 of the recording head 6. By moving it, the inclination angle of the recording head 16 is changed, and since the slide lever 13 itself serves as a switch, the inclination angle of the recording head 6 at that time can be recognized.

Once the inclination angle α° of the recording head 6 is detected, the various corrections described above become possible.

First, positional deviation correction will be explained.

As shown in FIG. 5, depending on the inclination of the recording head 6, ΔX
, a positional shift occurs by Δy. If the distance from the first pin 8, which is the fulcrum, to the Nth heating element 22 is S, and the angle is β, then ΔX and Δy are respectively Δx=s(cos(β−α)−bulkβ) Δy= s(sinβ-8ln(β-α)).

For ΔX correction, delay the recording start timing,
It is sufficient to start recording after the carriage 4 has gone too far by ΔX.

Regarding Δy correction, in the initial state, the paper feed mechanism (
It is possible to move the recording paper t'1 back by Δy using the method (not shown). However, since the values of both ΔX and Δy are small, there is no practical problem even if the positional deviation correction is omitted.

Next, character width correction will be explained.

Even if the character height if is changed by changing the inclination angle of the recording head 6, if the character width is always constant, it is difficult to say that the character size is variable. Therefore, it is necessary to change the character width in accordance with the character height l. There are two methods to change the character width:

(I) Carriage speed control method This is a method in which the drive period T of the thermal head is kept constant and the moving speed of the carriage 4 is varied.If the carriage speed is slowed down, the character width becomes smaller.

FIG. 7 is a functional block diagram for realizing the carriage speed control method.

In the figure, reference numeral 71 denotes a central processing unit (CPU), to which a detection signal from the inclination angle detection means of the inclination angle switching device, for example, the sensor 16 is input, and the detected recording head inclination angle α is input to the CPU 71. In response, the CPU 71 sends an angle status signal to the frequency conversion circuit 72.

In the frequency conversion circuit 72, a drive frequency corresponding to each recording head inclination angle α is set, and a drive frequency f is selected by the angle status signal from the CPU 71, and this drive frequency f is given to the carriage motor driver 73. , a carriage motor 74 is driven by the carriage motor driver 73.

Now, when the inclination angle of the recording head 6 is α°, if the thermal head driving period kT + character width is the space between nine characters kr (character pitch P-=b+r), then the carriage movement speed vH can be calculated by the following equation (1). It will be done.

V = P / n T = (b + r ) / nT ...... (1) However, n is the dot matrix (N
Xn) in the horizontal direction.

If the character width S is equal to the character height l, then (actually, the character width is made slightly smaller than the character height.

) The above equation (1) becomes as follows.

V-('10% T-(d(jlls a+ % T,
, , , , L2) Therefore, the driving frequency f is (where D is the pulley pitch diameter), and according to this formula (3), one driving frequency f for each inclination angle α is the frequency conversion circuit 7.
Output from 2.

In this way, in the above equation (2), the only variable is α, and the rest are constants, so when the value of the inclination angle α° is detected, the carriage speed is determined.

When compared with the carriage speed VQ when the tilt angle is 0°, the following equation is obtained.

dcosa+r V/Vo-□ ......(4) d+r Then, with the speed ratio according to equation (4) using the carriage speed control function block shown in FIG. 7 above,
The carriage 4 is driven to obtain a character width corresponding to the character height l.

(m thermal spatula) Drive MI period control method This is a method in which the carriage speed Vi is kept constant and the thermal head drive cycle T is varied.If the drive cycle T of the thermal head is shortened, the character width becomes smaller.

FIG. 8 is a functional block diagram for realizing the thermal head drive cycle control method.

In the figure, 81 is a central processing unit (CPU),
The CPU 81 receives a detection signal from the inclination angle detecting means of the inclination angle switching device, for example, the sensor I6, and the CPU 8
1 sends an angle status signal to frequency selection circuit 82.

In the frequency selection circuit 82, a driving frequency F corresponding to each recording head inclination angle α is set, and the driving frequency F is selected by the angle status signal from the CPU 8, and this driving frequency F is given to the head driver 83. recorded.

Now, when the inclination angle of the recording head 6 is α0, the carriage speed is 'Iv, and the character width is one character space r (character pitch P=b+r), the thermal head drive period T is expressed by the following equation.

T = b +/ny ...... (5) However, n
is the dot matrix (NXn) that makes up the entire character.
) is the number in the horizontal direction.

If the character width is equal to the character height l, then the above (5
) formula becomes as follows.

Therefore, the driving frequency F becomes ---, and the driving frequency F for each inclination angle α is outputted from the frequency selection circuit 82 according to this equation (7).

In this way, in the above equation (6), the only variable is α, and if the value of the inclination angle α° is detected, the thermal head drive period T is determined. When compared with the thermal head drive period To when the inclination angle is 0°, the following equation is obtained.

Poem o = d cm” + yd+ r ・・・-1
81 Then, by using the thermal head drive cycle control function block shown in FIG. 8, the thermal head drive cycle is shortened by the cycle ratio according to equation (8), and a character width corresponding to the character height l can be obtained.

Next, correction of the inclination of the print result will be explained.

As described above, since the heating element row 20 is tilted, if a heating signal is applied to each heating element at the same timing, the printing result will naturally also be tilted. Therefore, the Nth heating element 22
The application timing is sequentially shifted from the first heating element 21 to the first heating element 21. The delay time ti of the signal applied to each heating element is determined by the inclination angle α° of the recording head 6. When the inclination angle of the recording head 6 is α°, from the Nth heating element 22 to the ith heating element 22
The distance in the X direction to the th heating element is determined by the following formula.

By dividing this by the carriage speed V, the delay time ti of the signal applied to the i-th heating element is determined.

-t ti=-dsinα ・・・・・・(lO)N 慟 ■ From the above formula, the delay time t1 to tN of the signal applied to each heating element
eCan be set for each inclination angle.

Therefore, correction of the slope is realized by delaying the applied signal of each heating element by ti.

FIG. 9 is a block diagram for fully realizing this tilt correction.

In FIG. 9, 91 is a central processing unit (CPU), 92 is a character generator (CG), 93 is a delay circuit means that can set a delay time, 94 is a head driver, and the character generator 92 applies voltage to each heating element. The signals are output as data and each signal is delayed by t1 by the delay circuit means 93. That is, the delay time ti is determined by the rotation angle α of the head as shown in the above equation (10).
However, the delay circuit means 93 is C
The basic delay time is determined based on the status signal indicating the magnitude of the rotation angle α sent from the PU 91. The input data signals are then delayed and applied to the head driver 94 to drive the head and correct the inclination of the characters.

FIG. 10 is a timing diagram showing the delay time of each signal.

As is clear from the above equation (10), there is no need to delay the signal applied to the Nth heating element. Furthermore, if the delay time of the signal applied to the N-1th heating element is tl, then the formula (
10), the delay time of the applied signal to the N-2th heating element is twice tl, and similarly, the delay time of the applied signal to the N-3rd heating element is three times tl, and the delay time of the applied signal to the N-4th heating element is 3 times tl. It is 4 times that of the N−ith (rii times that of the second −
:N-2 times, the first part 7'12 becomes N-1 times. In this way, the delay time of the signal applied to each heating element is 10 times
As shown in the figure, the delay time is a natural number multiple of the delay time of the N-1th heating element.

FIG. 11 is a block diagram showing a specific example of the configuration of the second delay circuit means 93.

In FIG. 11, clock generation circuits Cα1 to Cαm are circuits that generate a clock with a period corresponding to the head rotation angle (angle status signal) α sent from the CPU 91 (FIG. 9), and this period is N. - It is set to the delay time of the applied signal of the first heating element. Each of these clocks is synchronized with a print synchronization signal, and each time a print line changes, the clock is set υ to eliminate horizontal deviation of characters.

Further, each clock outputted from the clock generation circuits Cα1 to Cαm is selected by a multiplexer M1 and sent to the clock input of each shift register SRI to 5Rn-i. Multiplexer MljdCPU91 (Figure 9)
A clock corresponding to the rotation angle is selected based on the status signal of the rotation angle α of the head. Note that clocks corresponding to all rotation angles are generated by the clock generation circuits Cα1 to Cα□.

Figure 12 shows the shift register SRI~5 shown in Figure 11.
It is a timing diagram of Rn-.

In FIG. 12, the clock input (a) is the clock generated by the clock generation circuit in FIG. 11, and the data from the CG in FIG. 11 corresponds to the data input (b) in FIG. 12, Data from this CG is delayed and output as a signal applied to the heating element.

That is, the way the data appears in Figure 12. □-1 is the clock period 1. from data input (b). There is a delay in data output Q. -2 is twice that, and Qn-3 is three times that, so that each is delayed by a natural number multiple of the clock input t1.

As mentioned above, the delay time of each heating element is jdN - a natural number multiple of the delay time of the 1st heating element. By selecting the input, each heating element can be converted into the equation (
It becomes possible to delay by the value of 10).

The multiplexer M2 is used to send all data from the CG directly to the head driver when the head rotation speed is 0, and the head rotation angle α is the same status signal as the multiplexer M1.

Further, in FIG. 11, data D1 from CG is the applied signal of the first heating element, and D2, DB
,..., Dn are the second, third,..., respectively.

The signal applied to the Nth heating element is shown.

Note that in FIG. 11, t2 represents an error in delay time. This error is caused by shifting at the rising edge of the clock input, and the error can be reduced by multiplying the frequency of the clock input by an integral number and using the data output shifted by that number.

For example, in Figure 12, one-third of the period you want to delay
If the clock is used as the clock input, the data output Qn-
1 is delayed by three times the period of the clock input, that is, the period to be delayed, and the error in the delay time can be made into IA. Note that in this case, the number of shift registers used increases.

In the above embodiment, a shift register is used, but 7
It may also be configured as a lip flop.

In this way, even if the inclination angle of the recording head 6 is changed using the application timing control function block configuration shown in FIGS. 9 and 11, the printed result will not be tilted and a normal font will be obtained.

In the above embodiments, an ink ribbon stationary type was described, but it can be applied to an ink ribbon mounted type (a method in which an ink ribbon is mounted on the carriage 4) thermal transfer serial printer, and is not limited to a thermal transfer printer. Needless to say, the present invention can be applied to printers equipped with a complete array of printing elements, such as ordinary thermal printers and pressure printers.

<Effects of the Invention> As described above, according to the present invention, the recording head number changing means is provided, and the operation timing of each printing element is changed in accordance with each inclination angle, so that all several character sizes can be selected. Because of this structure, many different character sizes can be produced using the same recording head.

Therefore, it is not necessary to prepare many types of recording heads depending on the character size, and the desired print character size can be obtained without the need for the troublesome work of replacing the recording heads.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the configuration of a conventional thermal transfer serial printer with variable character size using an exchangeable recording head; Fig. 2 is a perspective view showing an attachment/detachment mechanism for replacing the recording head;
The figure is a perspective view showing a partial configuration of a variable character size thermal transfer serial printer embodying the present invention, FIG. 4 is a diagram showing the configuration of a recording head inclination angle switching device of the present invention, and FIG. Figure 6 is an enlarged view of the heating element part when the slide lever position is detected and recorded in four stages.
” (24) is a functional block diagram when implementing the carriage speed control method, Figure 8 is a functional block diagram when implementing the thermal head drive cycle control method, and Figure 9 is a block diagram for implementing tilt correction. Fig. 10 is a timing diagram showing the delay time of each signal, Fig. 11 is a block diagram showing a specific example of the structure of the delay circuit means, and Fig. 12 is a timing diagram of the shift register. ...recording paper, 2...platen, 4...carriage, 6...recording head, 7...recording head holder,
14...Manual knob, +5...Character size scale, 2
0...Heating element row. Agent Patent attorney Aihiko Fukushi (and 2 other people) Kito^, 0 Ya 9 Kugaha Kugai machine de I Ku9 Kite Q+ ≧ Go to the village ~ Shima”6
-, t'-4den

Claims (1)

[Scope of Claims] 1. A printing device in which a carriage equipped with a recording head having an array of printing elements is reciprocated parallel to a platen and perpendicular to a paper feeding direction, and the recording head prints on recording paper, comprising: The apparatus is provided with an angle switching means for tilting the print element array by tilting the head in several stages, and is configured to select character sizes in several stages by changing the operation timing of each printing element corresponding to each tilt angle. 'f: Characteristic variable character size printing device. 2. The variable character size printing device according to claim 1, further comprising a heating element array as the printing element array.