JPH02111558A - Printing density regulation system - Google Patents

Abstract

PURPOSE:To make increase of capacity of a power source useless by a method wherein when printing is recognized to be light, printing is made dark by increas ing impact force to be given to a pin and besides, increase of temperature of a head is restrained within a limit by decreasing printing speed. CONSTITUTION:An indication means 10 indicating change-over of printing densi ty, an increasing means 12 increasing an energy amount to be supplied to each winding of a head 2 by a specific amount based on the indication of said indica tion means 10, and a control means 7 varying space speed of a carrier 15 are established. In the case where the indication means 10 indicates that the printing density is to be made dark by this structure, impact force of a pin is increased to perform printing by increasing an energy amount to be supplied to the wind ing of the selected head 2. Besides, the space speed of the carrier 15 is decreased to a predetermined speed so that average of total energy amount to be supplied to the head 2 becomes almost equal to that in the case where the indication means 10 does not indicate that the printing density is darkened.

Description

[Detailed Description of the Invention] [Table of Contents] Overview Industrial Application Fields Conventional Technology Problems to be Solved by the Invention Means for Solving the Problems Action Examples Effects of the Invention [Summary] Impact-type dot printers with high printing density If thin,
Regarding the print density adjustment method, which increases the impact force, limits the temperature rise of the head, and prevents the power supply capacity from increasing, when the print is thin, the impact force applied to the pins is increased, and the printing speed is reduced to prevent the head from increasing. The purpose of this printer is to limit temperature rise and provide a printer that does not require an increase in power supply capacity.It is equipped with a sensor that detects the temperature of the head, and uses an impact force that corresponds to the amount of energy supplied to the head winding to drive the pins. In a dot printer that detects the timing of driving each pin and prints by causing the carrier to perform a spacing operation, there is an instruction means for instructing the switching of print density, and each winding is changed based on the instruction from the instruction means. increasing means for increasing the amount of energy supplied to the printer by a predetermined amount; and control means for increasing the printing density, and when the instruction means issues an instruction to increase the print density, the amount of energy supplied to the winding of the selected head is increased.1. When the sensor detects that the head has reached a predetermined temperature, the space speed of the carrier is reduced to a predetermined speed.

[Industrial application field]

The present invention relates to an impact type dot printer, and in particular, when printing with a normally used impact force, when the print density is low, the impact force is increased, the temperature rise of the head is limited, and the power capacity is not increased. Related to print density adjustment method.

Impact-type dot line printers, which are equipped with multiple heads and print using a shuttle system, place paper and ribbon between the platen and the heads, and drive pins on the heads to create a set of doors (doors) that correspond to character patterns. Characters are formed and printed depending on the type of printer, but as the number of copies increases, the impact force of each pin becomes insufficient and the print becomes faint.

In this case, it is desirable to increase the impact force applied to the pins to increase the print density, but in order to increase the impact force, it is necessary to increase the amount of energy supplied to the head.

However, even if the amount of energy supplied to the head is increased,
It is necessary that the temperature of the head does not exceed the limit, that the printing speed does not decrease drastically, and that the power supply capacity does not become insufficient.

[Conventional technology]

FIG. 6 is a diagram illustrating an example of an impact type tontoline printer.

When the printer is viewed from above, a plurality of heads 2 are arranged facing a platen 1, and between the platen 1 and the heads 2 there are a ribbon 3 and a paper 6 shown by a dotted line.

The plurality of heads 2 are mounted on the same carrier (not shown), and while reciprocating in the direction of arrow A-B by this carrier, the pins (not shown) are moved in the direction of the ribbon 3 with a predetermined impact force. the platen 1.
Printing is performed on the tlE 6 set between the tlE and the ribbon 3. That is, each head 2 is provided with a plurality of pins, and a driving pin for driving the pin is provided for each bin. Eight wires are provided. Then, by passing a driving current through the windings of only the pins selected in accordance with the character pattern, the pins are driven to protrude in the direction of the ribbon 3.

As the ribbon 3 moves in space, the ribbon 3 is moved in the direction of arrow C by a roller 5 driven and rotated by a motor (not shown), pulled out from the ribbon cassette 4, and placed between the head 2 and the paper 6. , and returns to the ribbon cassette 4.

Conventionally, when such an impact type dot line printer prints on a plurality of sheets at the same time, the print becomes faint. Therefore, the operator has made the distance between the head 2 and the platen l narrower than the appropriate value to increase the impact force applied to the paper 6.

[Problem to be solved by the invention]

As mentioned above, conventionally, when the print density is low, the gap is narrower than the appropriate value, but in this method, many heads are lined up, so if the gap between the ribbon 3 and the head 2 becomes narrow, the gap between the head 2 and the ribbon 3 The frictional force between the ribbon 3 and the head 2 increases, making it easier for the ribbon 3 to travel and the carrier that conveys the head 2 to be obstructed, causing ribbon jams, and the pins of the head 2 getting caught on the ribbon 3 and damaging the pins. This was also a hindrance factor.

In order to avoid such adverse effects, it is conceivable to set the drive current applied to the winding at a high level to constantly apply excessive impact force to the pin. However, this method has the problem of increasing power consumption and requiring a means to prevent the temperature of the head 2 from rising, increasing costs and accelerating the wear of the platen.

In view of these problems, the present invention increases the impact force applied to the pins to increase the density of the print when the operator recognizes that the print is light, and at the same time reduces the printing speed to limit the temperature rise of the head 2. It is an object of the present invention to provide a printer that does not require an increase in power supply capacity.

[Means to solve the problem]

FIG. 1 is a block diagram of the principle of the present invention.

The control means 7 develops a character pattern for one line on the RAM 8 based on the print data given from the host device via the interface circuit 9, and then sends it to the head 2 via the head control circuit 11 for printing.

At the same time, the control means 7 drives the space motor 16 via the space control circuit 14 to move the carrier 15 and position the head 2 mounted on the carrier 15 at a predetermined printing position. A space operation is performed in which the space is moved along with the printing.

Then, the space control circuit 14 detects the position of the head 2 from the carrier 15 and sends the timing for supplying energy to the winding of the head 2 to the head control circuit 11.

When the printing for one line is completed, the control means 7 drives the line feed motor 18 via the line feed control circuit 17 to feed the paper.

The instruction means 10 sends a signal to the control means 7 in response to an operator's operation, and instructs the control means 7 to increase the print density. When the control means 7 receives this instruction, it controls the increasing means 12 of the head control circuit 11 to increase the amount of energy supplied to the winding of the head 2 by a predetermined amount.

Further, when the instruction means 10 issues an instruction to increase the print density, the control means 7 controls the space control circuit 14 to reduce the space speed to a predetermined speed. This decreasing space velocity is due to the decrease in space velocity.
Experiments were conducted in advance so that the timing of supplying energy to the winding of head 2 was delayed so that the average of the total amount of energy supplied to head 2 was approximately equal to the average of the total amount of energy when printing at normal density. Determined by etc.

Furthermore, when the instruction means 10 issues an instruction to increase the print density, the control means 7 causes the sensor 13 to control the head control circuit 11.
The temperature of the head 2 is monitored, and when the temperature of the head 2 reaches a predetermined temperature, that is, the permissible limit value, the space control circuit 1
4 to reduce the space speed to a predetermined speed in the same manner as above.

Further, when the control means 7 reads out the character pattern for one line developed on the RAMa and sends it to the head control circuit 11,
When the instruction means 10 issues an instruction to increase the print density,
The number of windings of the head 2 that are simultaneously driven is limited to a predetermined number.

- In impact type dot line printers,
To protect the power supply, the number of windings of the head 2 that is simultaneously excited and the printing density for each line are limited, and if the number of 1'4 lines that are simultaneously driven is greater than a predetermined value, it is equipped with a function to perform split printing. However, by using this function to increase the amount of energy supplied to the windings in order to increase the print density, by reducing the number of windings (pins) of the head 2 that is driven at the same time, the power consumption becomes approximately equal. Control as follows.

[Effect]

With the above configuration, when the instruction means 10 instructs to increase the print density, the increasing means 12 increases the amount of energy supplied to the winding of the head 2, thereby increasing the impact force of the pin driven by the winding. This makes it possible to increase the print density and increase the print density.

By the way, when the instruction means 10 issues an instruction to increase the print density, the increasing means 12 increases the amount of energy supplied to the winding of the head 2 as described above, so that the temperature of the head 2 increases when printing at the normal print density. When the printing speed increases and the winding burnout prevention mechanism of the head 2 provided in the impact type dot line printer operates, the printing speed decreases extremely.

This reduces the number of windings of the head 2 that is driven simultaneously, and -
This is because the printing of a line is performed by multiple space operations, and the printing of -characters is performed by dividing into multiple times.In order to prevent an extreme drop in printing speed, the operation of this winding burnout prevention mechanism is necessary. It is necessary to prevent this.

In order to prevent the winding burnout prevention mechanism from operating, the average amount of total energy supplied to the head 2 may be made to be approximately the same when the printing density is increased and when normal printing is performed. Therefore, the present invention prevents the printing speed from decreasing excessively by reducing the space speed.

That is, the control means 7 reduces the space speed of the space control circuit 14 when the instruction means 10 issues an instruction to increase the print density. Since the head control circuit 11 sends excitation current to the winding of the head 2 according to the excitation timing sent out by the space control circuit 14, it is possible to reduce the average amount of total energy supplied to the head 2 by the amount of space speed reduction. Therefore, the temperature rise of the head 2 can be suppressed within limits.

Furthermore, since the sensor 13 notifies the control means 7 that the temperature rise of the head 2 has reached the permissible limit value, the control means 7 reduces the space speed at this point, thereby reducing the printing speed as much as possible. can be prevented.

This is because, in actual use, it is rare for the head 2 to continue printing characters with such high print density that the winding burnout prevention mechanism operates.

Further, the control means 7 controls the 1! of the head 2 in order to increase the print density. Since the maximum number of windings of the simultaneously driven head 2 is reduced by the amount of energy supplied to the wire, the maximum power consumption can be made equal to that of Urajo printing. Therefore, it is possible to prevent the power supply capacity from increasing in order to increase the print density.

〔Example〕

FIG. 2 is a block diagram of a circuit showing one embodiment of the present invention.

The same reference numerals as in FIG. 1 indicate the same functions. The processor 19 operates by reading the program stored in the ROM 20, develops a character pattern for one line on the RAMa based on the print data given from the host device via the interface circuit 9, and then outputs the character pattern to the spatula I via the head control circuit 11. ”
2 to perform printing.

At this time, the processor 19 simultaneously controls the space control circuit 14.
After the space motor 16 is driven to move the carrier 15 and the head 2 mounted on the carrier 15 is positioned at a predetermined printing position, a space operation is performed in which the head 2 is moved together with printing.

Then, the space control circuit 14 detects the position of the head 2 from the carrier 15 and sends the excitation timing for supplying energy to one winding of the head 2 to the head control circuit 11.

When the printing of one line is completed, the processor 19 drives the line feed motor 18 via the line feed control circuit 17 to feed the paper.

When the switch 22 provided on the operator panel 21 is pressed, the processor 19 recognizes that this is an instruction to increase the print density, and activates the increasing means 12 of the head control circuit 11.
is controlled to increase the amount of energy supplied to the winding of the head 2 by a predetermined amount.

This switch 22 is a digital switch, and is used to input multilevel digital values corresponding to a desired density.

FIG. 3 is a block diagram illustrating an example of the head control circuit, and FIG. 4 is a diagram illustrating the operation of FIG. 3.

FIG. 3 fa) shows a case where the amount of energy supplied to the winding of the head 2 is increased by lengthening the supply time of the current supplied to the winding of the head 2.

"I" is input as data to drive the winding 32 of the head 2 from the terminal A1, and as described above, the excitation timing is input from the space control circuit 14 to the terminal B as shown in FIG. When the excitation timing is input from the terminal B, the timer 23 outputs the AND circuit 2 for a predetermined time "'1" as shown in FIG.
4, the AND circuit 24 sets the timer 23 to "1".
”, a “1” is sent to the transistor 28.

Therefore, the transistor 28 is turned on, and an excitation current flows from the power source V11 through the winding 32 of the head 2 to the transistor 28, and a constant voltage is generated at the resistor 30. This voltage is sent to the operational amplifier 26, where it is compared with the reference voltage sent out by the reference voltage generation circuit 34.

The operational amplifier 26 controls the base potential of the transistor 28 so that the potential between the resistor 30 and the transistor 28 becomes equal to the potential generated by the reference voltage generation circuit 34.

Therefore, operational amplifier 26 is configured to cause a constant current to flow through winding 32 determined by the reference voltage. Wholesale.

The head 2 is provided with a plurality of (for example, 24) windings 32 to 33 per - head, and the head control circuit 11 also includes transistors 28 to 33, respectively, corresponding to the 24 windings 32 to 33. 29 and operational amplifiers 26 to 27 and AN
D circuits 24-25 are provided. That is, I winding 3
3, there are a transistor 29, a resistor 31, an operational amplifier 27, and an AND circuit 25, and the operation is the same as above except that data for driving the winding 33 is input from the terminal AN, so a detailed explanation will be omitted. .

When the switch 22 on the operator panel 21 is pressed,
A signal to make the print darker is manually input to the timer 23 via terminal C. When this signal is input to the timer 23, when the excitation timing is input to the terminal B, the timer 23 outputs the timer output in Fig. 4 (al).
As shown in FIG. 2, the time for sending "l" to the AND circuit 24 is lengthened by a predetermined time.

That is, the time period during which the current supplied to the partial windings 32 to 33 indicated by diagonal lines in the timer output (2) flows is lengthened.

This makes it possible to adjust the print density according to the operator's wishes.

The timer 23 is configured such that a time corresponding to multi-level concentration information given via the switch 22 can be set via a terminal C.

FIG. 3 (bl) shows the case where the amount of energy supplied to the 18 wires of the head 2 is increased by increasing the current value supplied to the windings of the head 2.

The same reference numerals as in FIG. 3(a) indicate the same functions.

Since a voltage is applied to the base of the transistor 36 from the power source VC via the resistor, the transistor 36 is turned on and short-circuits the resistor R1. Therefore, assuming that the voltage across the Zener diode 35 is 2, the reference voltage sent to the operational amplifiers 26 to 27 is a voltage obtained by dividing this v2 by the resistors R1 and R2. That is, reference voltage = Rz / (R + + R2)
It is V2-■.

Therefore, as shown in the excitation timing in FIG. 4(b), depending on the excitation timing input to terminal B, the windings 32 to 33
As shown in FIG. 4 (winding current (2) in BL), a constant current determined by the four quasi-voltages shown by equation 0 flows through the winding current.

When the switch 22 on the operator panel 21 is pressed,
A signal for making the print darker is input to the transistor 36 via the terminal C. That is, since a signal is input to ground the base of the transistor 36, the transistor 36 is turned off.
The reference voltage sent to the operational amplifiers 26 and 27 is (R2+R,)/(R+ +R, +Ri)xV2-■.

Since the reference voltage determined by the 0 formula is higher than the reference voltage determined by the 0 formula, the voltage generated across the resistors 30 to 31 increases by that amount, and the operational amplifiers 26 to 27 increase the current flowing through the windings 32 to 33. , the amount is increased by that amount (
It will be washed away. That is, as shown in the winding current (2) in FIG. 4 (bl), a current larger than the current value shown by the winding current (2) by an amount indicated by diagonal lines is caused to flow.

When the switch 22 is pressed and the processor 19 instructs to increase the print density, the processor 19 controls the space control circuit 14 to reduce the space speed to a predetermined speed.

FIG. 5 is a diagram illustrating the reduction in heat generation of the winding.

When performing regular printing, the current for printing with the normal impact force is applied to the winding 32 of the head 2 based on the excitation timing corresponding to the normal space speed, as shown in excitation timing ■, and as shown in winding current ■. ~33.

When the switch 22 is pressed, as shown in excitation timing ■, the winding current [[
A current with a longer supply time or a current with an increased current value as shown in phase] or (1) is supplied to the windings 32 to 33.

That is, this excitation timing is determined by the pulse output of the position detection sensor provided on the carrier 15, and changes in the same way as the pulse interval, which changes according to the moving speed of the carrier 15, so that it changes in conjunction with the decrease in carrier speed change. , the interval between excitation timings also becomes wider.

When printing darker in this way, the space speed is lowered and the sending interval of excitation timing is lengthened, but the head 2
The space speed is set in advance so that the average of the total amount of energy supplied to each of the 18 lines is approximately equal to the average of the total amount of energy when printing at normal density.

Further, when the switch 22 is pressed and an instruction is given to increase the print density, the processor 19 monitors the temperature sent by the sensor 13 through the head control circuit 11, and when the temperature of the head 2 reaches the permissible limit value. , controls the space control circuit 14 to reduce the space speed to a predetermined speed.

Furthermore, when the processor 19 reads out the character pattern for one line developed on the RAMB and sends it to the head control circuit 11, if the switch 22 is pressed and an instruction is given to increase the print density, the head that is driven at the same time The number of windings in step 2 is limited to a predetermined number.

That is, if the number of windings driven simultaneously is greater than a predetermined value,
In order to increase the print density by using the division printing function, the amount of energy supplied to the winding wire is increased, and the head 2
By reducing the number of dot pins (for example, 24) to be driven, the number of windings of the head 2 that are simultaneously driven is reduced, and the power consumption is controlled to be approximately equal.

〔Effect of the invention〕

As explained above, the present invention allows printing to be made darker when the operator deems it necessary, and also prevents the print head temperature from rising and the printing speed from drastically decreasing when making the printing darker. Furthermore, since there is no need to unnecessarily increase the power supply capacity, an economical impact type dot line printer can be provided.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the principle of the present invention, Fig. 2 is a block diagram of a circuit showing an embodiment of the present invention, Fig. 3 is a block diagram illustrating an example of a head control circuit, and Fig. 4 is a block diagram illustrating an example of a head control circuit. 3, FIG. 5 is a diagram illustrating the reduction in heat generation of the winding, and FIG. 6 is a diagram illustrating an example of an impact type dot line printer. In the figure, 1 is a platen, 2 is a head, 3 is a ribbon,
4 is a ribbon cassette, 5 is a roller,
6 is paper, 7 is control means, 8 is RAM, 9 is interface circuit, 10 is instruction means, 11 is head control circuit, 12
is an increasing means, 13 is a sensor, 14 is a space control circuit, 15 is a carrier, 16 is a space motor, 1
7 is a line feed control circuit, 18 is a line feed motor, 19 is a processor, 20 is a ROM, 21 is an operator panel, 22 is a switch, 23 is a timer,
24.25 is an AND circuit, 26.27 is an operational amplifier,
28, 29, 36 are transistors, 30, 31 are resistors, 32, 33 are windings, 34 are reference voltage generation circuits, Figure (a) An example of a head loop path House-g4-t love block 2m stone map (F/) j) Wooden four-car practical color ri? Showing times τ each time 2 Figures Figure '\r Season f! P circuit i-i+1 as 13 and shi91 Rob "0・, t2Uη^ False (M's 2) (d) Dirty force timing (Figure 3/) Diagram explaining operation 2 % figure

Claims (1)

[Claims] 1) Instructing to switch the print density in a dot printer that prints by driving each pin with an impact force corresponding to the amount of energy supplied to each winding of the head (2). An instruction means (10) and an increasing means (12) for increasing the amount of energy supplied to each winding of the head (2) by a predetermined amount based on the instruction of the instruction means (10), the instruction means When (10) issues an instruction to increase print density, the amount of energy supplied to the winding of the selected head (2) is increased, and the impact force of the pin is increased to perform printing. Print density adjustment method. 2) By driving each pin with an impact force corresponding to the amount of energy supplied to each winding of the head (2), and causing the carrier (15) on which the head (2) is mounted to perform a space motion. , a dot printer that performs serial printing by detecting the timing of driving each pin, which includes an instruction means (10) for instructing switching of print density, and based on the instruction from the instruction means (10), the head (2) increasing means (12) for increasing the amount of energy supplied to each winding of the carrier (15) by a predetermined amount;
), and when the instruction means (10) instructs to increase the print density, the amount of energy supplied to the winding of the selected head (2) is controlled. In the case where the instruction means (10) does not instruct to increase the density of printing, the average of the total amount of energy supplied to the head (2) increases and the impact force of the pin is increased to perform printing. so that it is approximately equal to
A printing density adjustment method characterized by reducing the space speed of the carrier (15) to a predetermined speed. 3) It is equipped with a sensor (13) that detects the temperature of the head (2), and drives each pin with an impact force corresponding to the amount of energy supplied to each winding of the head (2). In a dot printer that performs serial printing by detecting the timing of driving each pin by making the carrier (15) equipped with 2) perform a spacing operation, the instruction means (10) for instructing the switching of print density; , increasing means (12) for increasing the amount of energy supplied to each winding of the head (2) by a predetermined amount based on an instruction from the indicating means (10); and the indicating means (10) for switching the print density. After instructing
When the sensor (13) detects that the temperature of the head (2) has increased to a predetermined temperature, the carrier (15)
), and when the instruction means (10) instructs to increase the print density, the amount of energy supplied to the winding of the selected head (2) is controlled. When the sensor (13) detects that the temperature of the head (2) has reached a predetermined temperature, the pin is supplied to the head (2). The space speed of the carrier (15) is reduced to a predetermined speed so that the average of the total energy amount is approximately equal to that when the instruction means (10) does not instruct to increase the print density. Characteristic print density adjustment method. 4) In a dot printer that prints by driving each pin with an impact force corresponding to the amount of energy supplied to each winding of the head (2), an instruction means (10) for instructing switching of print density; , increasing means (12) for increasing the amount of energy supplied to each winding of the head (2) by a predetermined amount based on an instruction from the indicating means (10); control means (7) for limiting the number to a predetermined number;
0) gives an instruction to increase the printing density, the amount of energy supplied to the winding of the selected head (2) is increased, the impact force of the pin is increased, printing is performed, and the head (2) is ), the number of windings of the head (2) to be driven at the same time is limited so that the average of the total amount of energy supplied to the head (2) is approximately equal to that when the instruction means (10) does not issue an instruction to increase print density. Print density adjustment method featuring: