JPS606482A - Paper feed method of thermal recording apparatus - Google Patents

Abstract

PURPOSE:To prevent the generation of sticking noise, by substantially preventing the generation of the suspension period of paper feed during a fixable period by generating a plurality of motor pulses in a concentrated state when a printing pulse of each line is generated. CONSTITUTION:During a time when a paper feed speed is set to 50mm./s-50mm./m by a selection switch 2, a clock pulse (a) is subjected to frequency division by frequency divising circuits 3, 4 while a line pulse (c) having a pulse interval corresponding to a speed and a motor pulse (b) for dividing a pulse interval into four are generated and a motor 8 substantially continuously feeds heat-sensitive recording paper 7 without accompaning a suspension period resulting in the genertion of fixation to perform recording on the basis of a printing pulse (d). In the next step, when the paper feed speed is set to 25mm./m or less, a switch 14 is changed over and the line pulse (c) is divided into four motor pulses (e) by a motor pulse generating circuit 10 to generate said pulses (e) in a concentrated state at the point of time when the printing pulse (d) is generated while the heat- sensitive recording paper 7 is moved without substantially including a suspoension period and the generation of sticking can be eliminated even if a data amount increases.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper feeding method for a thermal recording device in which a step motor is used to feed thermal recording paper whose coloring layer melts and develops color due to heat generated by dot-shaped heating elements of a recording head. be.

When paper feeding is carried out using a step motor, it is not only easier to control the paper in an open loop;
It has the advantage of being able to change speeds over a wide range from low to high speeds without the need for gears, etc. However, on the other hand, since the paper feed is performed intermittently, vibrations in the mechanical system generate noise, which is a problem that becomes especially large at high speeds. arise. So, follow me.

Since then, in order to reduce this noise, one of the step motors has been
In addition to reducing the rotation angle of the step to reduce the vibration of the monitor, a deceleration mechanism is provided between the motor and the platen roller to reduce the amount of recording paper fed per step. A method of driving a step motor with motor pulses is known. However, according to this method, since the feed amount per step is small, sticking noise will occur at low speeds. This noise is generated when the coloring layer of thermal recording paper melts and colors, then hardens and sticks to the heating element, and then peels off. This is because the paper feeds almost continuously at high speeds. At low speeds, sticking occurs because the recording paper is fed intermittently. That is, at high speeds, paper is fed while the coloring layer is melting, but at low speeds, not only is the paper fed only a small amount compared to the dimensions of the heating element at each step, but there is also a pause period in paper feeding. By the time the next motor pulse is input, the melting period has passed and the paper is stuck, and therefore, after several steps of feed have been accumulated on the belt of the drive system, the recording paper peels off from the heating element and the recording paper is removed all at once. It moves, causing sticking noise and uneven feeding.

Therefore, the present invention provides a method for feeding paper in a thermal recording device using a step motor driven by a plurality of motor pulses for each line pulse, in order to prevent sticking noise from occurring even during low-speed paper feeding. The purpose is to

According to the present invention, this purpose is to intensively generate a plurality of motor pulses when printing pulses are generated for each line, so that the sticking possible period, that is, the recording paper temperature changes from the melting level (melting limit temperature) to the hardening level (sticking possible). This is achieved by virtually eliminating any pause period in the paper feed during the period when the temperature reaches the temperature limit.

The invention will now be explained on the basis of the illustrated circuit for implementing the method according to the invention.

In FIG. 1, 3 indicates a clock pulse a generated by a clock generator 1 at a paper feeding speed (5o).

25.10 and 5mm/8 and 50.25.10 and 5mm/m) A frequency dividing circuit that generates motor pulse b by counting down at a frequency division ratio corresponding to 10 and 5 mm/m, 4 is a frequency dividing circuit that generates motor pulse b by 1/4 The frequency dividing circuit 3, which generates the line pulse C by dividing the frequency into゜2.5.6.25.12.5.75
．． The frequency divider circuit 3 generates line pulses C with a pulse interval of 150.375.750 m5, while the frequency divider circuit 3 generates 1/4 period of each line pulse C,
motor pulses b are generated at a rate of . 5 is a recording section, which creates recording data corresponding to input information such as waveform data and character data in synchronization with the line pulse C, and applies a printing pulse d to the heating element at the corresponding dot position of the recording head 6. , 7 heads of thermal recording paper are recorded. Reference numeral 8 is a pulse-driven motor, such as a stepping motor, which conveys the thermal recording paper 7, and is driven by a motor pulse having a required pulse width and electric power in a driving section 9.

10 is a motor pulse generation circuit that generates four motor pulses e at 7 ms intervals in synchronization with line pulse C, and similarly counts down clock pulse a to generate 7 m
A frequency divider circuit 11 that generates pulses at intervals of s, and a circuit that operates to open an AND gate 12 by generating an output for a predetermined period (a time width that allows four motor pulses to pass) when line pulse C is supplied. It is composed of a shot multivibrator 13.

14 is a changeover switch that supplies motor pulse e from motor pulse generation circuit 10 to drive unit 9 when the paper feeding speed has decreased to such an extent as to cause sticking noise;
The switching is performed by a switching signal supplied through the speed selection switch 2. The paper feed speed at which sticking noise starts to occur varies depending on the power of the printing pulse, the characteristics of the thermal recording paper, the pressing force of the recording head, etc., but in this example, it was set to 25.
mm/m, and therefore, when the paper feed speed is set to one of 25, 10, and 5 mrn/m by the speed selection switch 2, a switching signal is supplied to the changeover switch 14.

The operation is as follows.

Paper feed speed is set to 50 mm/s by selection switch 2.
While the speed is set to 50 mm/m, the frequency of the clock pulse a is divided by frequency dividing circuits 3 and 4, and a line pulse C with a pulse interval M corresponding to the paper feeding speed is output from the frequency dividing port P114, and then the frequency dividing circuit 3 to d, a motor pulse b is generated which divides this pulse interval into four. Therefore, the motor 8 conveys the thermosensitive recording paper 7 virtually continuously without a pause period that causes sticking, and the recording section 5 sequentially creates recording data in synchronization with the line pulse C, and the recording head Recording is performed on the thermal recording paper 7 by applying a printing pulse d having a pulse width of 4 ms to the heating element at the corresponding dot position of 6.

The paper feed speed is controlled by switch 2! l) 25mm/m
When the following speeds are set, the changeover switch 14 automatically changes according to the changeover signal, and the motor pulse generation circuit 10
Select motor pulse e from . As a result, a line pulse C corresponding to the paper feeding speed is generated through the frequency dividing circuits 3 and 4 in a similar manner, and the motor pulse is
As shown in the figure, the one-shot multivibrator 13 is enabled to operate by the line pulse C, thereby opening the cyan gate 12 and changing to the motor pulse e at 7 ms intervals. When the four motor pulses e are generated, the output of the one-shot multivibrator 13 disappears, the AND gate 12 is closed, and the motor 8 is kept in a complete rest period until the pulse C on the third line is generated. Become. That is, the timing at which the four motor pulses e are generated is concentrated at the time when the printing pulse d is generated, and when the printing pulse d is applied to the heating element, the temperature at the position of the dot on the thermal recording paper 7 that comes into contact with it reaches at least the curing level. While crossing, the thermal recording paper 7 continuously moves with virtually no stopping period. As is clear from Fig. 2, this movement period is approximately 28m8, corresponding to four motor pulse periods, and after this period there is a pause period in which paper is not fed until the next printing pulse d is applied. become. In other words, when the recording paper 7 is conveyed at low speed, the selector switch 1
Motor pulse b from frequency divider circuit 3 without switching 4
If you select , as shown in Figure 2, there will be a pause period every time each motor pulse b occurs, and after the movement by the first motor pulse b that occurs at the same timing as the printing pulse d, there will be a period from the molten state to the hardening. Sufficient pause periods occur during the fixation, resulting in noise commensurate with the amount of data.

Even when the paper feed speed is set to 10 mm/m or 5 mm/m, the motor pulse generation circuit 10 generates the motor pulse e with the same timing as 25 mm/m, while the stop period corresponds to the paper feed speed. It's going to be long. Further, when concentrating motor pulses according to the method of the present invention, the motor pulses may be concentrated to the extent that sticking noise can be avoided, and the remaining motor pulses may have long pulse intervals, and the The generation start point does not have to coincide with the rising edge of the print pulse, and may be earlier or earlier within a permissible range depending on the circuit configuration.

As described above, according to the present invention, even when the paper is fed at low speed, there is no pause period required for fixation in the process of melting and coloring to hardening.
This solves the problem of sticking noise even when the amount of data increases. This allows paper feeding from low speed to high speed)
It becomes possible to realize a thermal recording device with less noise.

[Brief explanation of the drawing]

FIG. 1 shows an example of a circuit for implementing the method according to the present invention, and FIG. 2 shows waveforms of various parts thereof. 6...Recording head 10...Motor pulse generation circuit agent Masaharu Fukudome Figure 2 Procedural amendment (method) % formula % 1. Indication of the case 1982 Patent application No. 113651 2. Title of the invention Paper feeding method for thermal recording devices 3, relationship with the amended case Applicant Address: 1463 Nishitsuruga-cho, Tsuruga, Nagano City, Nagano Prefecture Name: Nagano Japan Radio Co., Ltd. (1 other person) 4.
Agent 〒166 Kinshilf0 Procedural amendment July 21, 1980 Clock [Y Secretary Manabu Shiga 1, Display of 1 yen 1981 Patent Application No. 113651 2, Title of invention Thermal type Paper feeding method of the recording device 3, person performing the drawing and relationship with the case Applicant address 1463 Nishitsuruga-cho, Tsuruga, Nagano City, Nagano Prefecture Name Nagano Japan Radio Co., Ltd. (and 1 other person) 4. Agent
〒151 6. Drawings in the detailed explanation column of the invention in the subject specification of supplementary IF? , ? II1. Contents of uE (11, page 4 line 9, page 6 line 6, page 6 line 8, page 6 line 13, page 7 line 5, page 8 line 18 (2 locations) and page 8 line 20
I will correct the line rmJ to rIDinJ. Masu. (3) In the same book, page 8, line 5, after ``...moves'', we will add ``so no sticking noise occurs''. (4) 0 In the same book, page 8, line 9, ``that is,'' will be corrected to ``in contrast to this.'' (5), Figures 1 and 2 will be corrected as shown in the attached sheet.

Claims (1)

[Claims] The thermal recording paper, which melts and develops color by applying a printing pulse to the heating element of the recording head, is intermittently fed by a motor driven by a plurality of motors synchronized with the printing pulse. In a paper feeding method for a thermal recording device, at least one of the plurality of motors is configured to move the thermal recording paper during a period during which the temperature of the thermal recording paper decreases from at least a melting level to a hardening level. A method characterized by generating pulses in a concentrated manner at the point in time when a printing pulse is generated.