JPS5915830B2 - printing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printing device used in a cash register or the like, and particularly to a printing device that performs parallel printing by a receipt/journal printer and a slip printer using a single control circuit.

An object of the present invention is to enable parallel printing by a receipt journal printer and a slip printer at low cost. Previously, receipts, journals, and slips were printed using three printers combined into one machine.

However, in this case, cash register buyers who rarely use slip printers do not need slip printers, and cash registers equipped with slip printers are seen as expensive and large. In order to eliminate this drawback, it is conceivable to combine receipt/journal printers into a cash register and add a slip printer as an option for customers who particularly require slip printing. This has the advantage that mass production effects for cash registers can be expected, and flexibility in terms of cash register design increases. However, in both serial printers and line printers, printing is generally performed by timing signals output from the printers, and simply arranging two printers requires control circuits for the two printers, which becomes expensive. In order to solve this problem, conventionally one control circuit,
A cash register is configured with a receipt/journal printer that operates in synchronization with the clock pulses output from this control circuit, and if a slip printer is required, it operates in synchronization with the clock pulses from the control circuit. There are devices that have a single control circuit by operating synchronously.

However, in this case, each printer requires an expensive and large drive source such as a pulse motor or synchronous motor.
The demand for cost reduction could not be met. The present invention aims to eliminate these drawbacks by using small, low-cost asynchronous motors in the master and slave printers, and
This enables parallel printing of master and slave printers using a single control circuit.

Embodiments of the present invention will be described with reference to FIGS. 1 to 4. 1st
Figure a is a schematic diagram of a receipt journal printer, which is the main printer, and Figure b is a schematic diagram of a slip printer, which is a slave printer. 1 is a wire dot printing type printing head, 2 is a bed to which print head 1 is attached, 3 is a pin that fits into a groove 6 made in bed 2 and can move vertically, and 4 can move bed 2 left and right. a guide shaft held in
5 is the timing belt with pin 3 attached, 7 is the motor 8
A gear train 9 for transmitting power from the clutch plate 10 is rotatably attached to the clutch plate 10 by means of a clutch lever.

Reference numeral 11 denotes a clutch pawl, which is rotated steadily by the rotation of the motor 8.

12 is a clutch spring which applies force so that the clutch lever 19 engages with the clutch pawl 11.

A clutch solenoid 13 rotates a trigger lever 14 against a trigger spring 15 to engage and disengage the clutch.

16 is a reed switch that generates a reference signal, 17 is a magnet, 18 is a gear that rotates integrally with the clutch plate 10, 19 is a pulley, 20 is a receipt, 21 is a journal,
In FIG. 1b, 22 is a slip, 23 is a head, 24 is a motor, 25 is a clutch plate, 26 is a clutch pawl, 27 is a clutch solenoid, and 28 is a reed switch.

In the above configuration, first, the motor 8 is rotated by a signal from the control circuit, and the clutch pawl 11 is rotated in the direction of arrow A via the gear train 7.

When the clutch solenoid 13 is operated, the trigger lever 14 rotates against the force of the trigger spring 15 and is disengaged from the clutch lever 19. The clutch lever 19 rotates by the force of the clutch spring 12 and engages with the clutch pawl 11. Therefore, the clutch plate 10 to which the clutch lever 19 is attached begins to rotate in the direction of arrow B integrally with the rotation of the clutch pawl 11. At this time, even if the electrical operation to the clutch solenoid 13 is released, the clutch plate 10 continues to rotate, and the timing belt No. 5 arrow C is applied via the gear 18 and pulley 19.
Drive in the direction of. Since the pin 3 attached to the timing belt 5 fits into the groove 8 of the bed 2 and is movable in the vertical direction, the head 1 reciprocates along the guide shaft 4 by the rotation of the pulley 19 in one direction. If the timing belt 5 is made to make one revolution for every one rotation of the clutch plate 10, the head 1 will also make one reciprocation. Next, let's talk about printing. The timing belt 5 is driven by the operation of the clutch described above,
Head 1 moves to the right. When the clutch plate 10 further rotates, the head 1 is reversed and moved to the left. Before and after the head is reversed, each is arranged so that the reed switch 16 is turned OFF by the action of the magnet 17 attached to the gear 18.The head 1 moves to the left and the reed switch 16 is turned OFF. The head 1 is activated by a signal (print ready signal) and a signal from a timing signal generator (not shown) (for example, the tacho energy output of the motor 8).
By applying a print drive signal for one dot at a time to , it is possible to print on the journal 21 and receipt 20 from the lower digit side. When the clutch plate is further rotated, the head that has finished printing one line is reversed and moved to the right. At this time, the receipt 20 and journal 21 are fed by one line by a mechanism not shown. When the clutch plate 10 further rotates, the trigger lever 14, which has already returned to its returned state, engages with the clutch lever 19, and the clutch lever 19 and clutch pawl 11 are disengaged, resulting in the state shown in FIG. 1a. Stop at. Accordingly, the head 1 also stops at the position shown in the figure, and the printing operation for one line is completed. When the next line is not printed, the motor 8 is stopped. When printing continuously, if the clutch solenoid 13 is operated just before the clutch plate rotates and the clutch lever 19 and trigger lever 14 engage, the clutch plate 10 continues to rotate without stopping. In this way, it is possible to eliminate losses in motor start-up time and clutch operation time, and increase the number of lines printed per unit time. The above is an explanation of the case where the receipt journal printer is operated independently. The slip printer shown in Fig. 1b also has a different paper feed and other attached mechanisms, but it basically has the same mechanism as the receipt/journal printer shown in a. When operated independently, it is similar to the receipt/journal printer. It becomes an action. Next, parallel printing, which is the gist of the present invention, will be explained. motor 8
, it is assumed that the motor 24 is a DC brush motor.

Further, the motor 8 and the motor 24 have a built-in tachogen, and the speed of each motor is controlled to be substantially constant by the signal from the tachogen. Since each motor is a DC brush motor, even if the speed is controlled, there is a phase shift, and the clutch pawl 11 and the clutch pawl 26 rotate without being out of phase. Therefore, when the clutch is actuated, heads 1 and 23 move out of phase. Further, the tachodynamic outputs of the motor 8 and the motor 24 are not synchronized.
Therefore, as it is, it is difficult to make the master and slave printers print in parallel using the same control circuit. In the present invention, the phases of the master and slave printers are matched immediately before the start of printing, and the slave printer also prints using a timing signal from the master printer, thereby enabling parallel printing. This will be explained in detail with reference to the timing diagram in FIG. A is the drive signal for the motor 8 of the main printer, B
is a drive signal for the motor 24 of the slave printer, C is a drive signal for the clutch solenoid 13, and D is a drive signal for the clutch solenoid 27.
E is the signal of the reed switch 16 which is a reference signal generator, F is the signal of the reed switch 28 of the slave printer, G is the motor brake signal of the main printer, H is the motor brake signal of the slave printer, I is the signal of the main printer motor 8
J is a signal obtained by waveform shaping the tachodynamic output of the motor 24 of the slave printer, K is a signal obtained by waveform shaping the tachodynamic output of the motor 24 of the slave printer
are print drive signals applied simultaneously to the heads of the master and slave printers, and TO-T3 and TO' represent respective times.

First, rotation signals are applied to the motors 8 and 24 of the master and slave printers (A, B). At the same time clutch solenoid 13
, 27 are each supplied with a drive signal of an appropriate pulse width.
The clutch plate 10 in figure a and the clutch plate 25 in figure b start to rotate (C, D). As mentioned above, the phases of heads 1 and 23 at this time are not in sync. If head 1 is ahead, reed switch 16 is ahead of reed switch 2.
0N earlier than 8 (E, F). Apply the brake to the motor 8 driving head 1 by this time difference (G)
. Head 1 and Head 23 if you adjust the brake strength appropriately.
The phase of the two can be matched. At time T1, head 1 and head 23 are almost simultaneously reversed and moved to the left. ~Then, at time T2, the reed switch 16 and the reed switch 28 are turned off almost simultaneously. On the other hand, pulses are output independently from the tachogen of the motor 8 and the motor 24 (1, J). Among these, using the tacho energy output 1 of the motor 8 of the main printer, printing is started from time T2 when the reed switch 16 is turned off. After one line of printing is completed, head 1 and head 23 are reversed and moved to the right at time T3.

In the case of one line printing, it is stopped by the operation of the clutch described above, but Fig. 2 shows the case where a signal is applied to the clutch solenoids 13 and 27 to continuously start printing the second line (C
,D).

Since the rotational speeds of the motors 8 and 24 are not equal at all, the ON signals of the reed switches 16 and 28 are different even in the second line printing cycle (E, F). Here, a case is shown in which the head 23 of the slave printer is in the lead. The motor 24 of the slave printer is braked by the difference between the signals of the read switch 16 and the read switch 28 (H
). As a result, the phases of heads 1 and 23 can be substantially matched. As described above, by applying the brake on the leading side of the master and slave printers just before starting printing, the phases of the master and slave printers are aligned, and by printing on both sides using the timing signal from the master printer, parallel printing is performed using one control circuit. Printing becomes possible easily. Next, an embodiment of the phase adjustment circuit will be described with reference to FIGS. 3 and 4.

The phase adjustment circuit according to the present invention is shown within the dotted line in FIG. The area outside the dotted line is a conventional speed control circuit with a brake.
is turned 0N-OFF to keep the speed of the motor 8 constant, and by setting the input terminal P to high, the transistor 31 is turned OFF.
At the same time, the transistor 33 is turned ON to apply a brake to the motor 8. In FIGS. 3 and 4, until the reed switch 16 and the reed switch 28 are closed, the signal P is low and the motor 8 rotates under speed control. If the main printer is ahead of the slave printer, the reed switch 16 closes before the reed switch 28, resulting in the signals shown in FIGS. 4L and 4M.
Therefore, the output G of the flip-flop output N1 phase adjustment circuit becomes as shown in FIG. In other words, the motor 8 of the main printer is braked by the amount that the main printer is ahead of the sub printer. If the slave printer is ahead of the master printer, the output G remains low and no brake is applied to the master printer. In Figures 3 and 4, only the phase adjustment circuit on the main printer side is shown, but if a similar phase adjustment circuit is installed on the slave printer side, the brakes will be applied to the motor on the leading side and the phase adjustment circuit of both printers will be adjusted. can be matched. As can be seen from the above embodiments, according to the present invention, by simply adding a simple phase adjustment circuit to the conventional printer drive circuit using an asynchronous motor, parallel printing of master and slave printers can be easily performed using one control circuit.

In the above embodiment, as a phase adjustment method, the brake is applied to the motor on the leading side, but the phase may be adjusted by strengthening the drive signal for the motor on the lagging side.

Further, although this embodiment has been described using a wire dot printing type serial printer, other line printers or serial printers may be used. Moreover, instead of printing in parallel with two master and slave printers, it is also possible to print in parallel by arranging a large number of slave printers in parallel to one main printer. In this case, for example, the slave printers may be placed in advance of the master printer, and the brakes may be applied to each slave printer to synchronize it with the master printer. In addition, in this example, 1
Although the reference signal is issued once during the printing cycle, it is possible that the reference signal is issued several times. Further, in this embodiment, the reference signal is emitted in synchronization with the printing operation, but if a reference signal generator is provided in a part of the gear train 7 in FIG. The motor 8 and the motor 24 can also be synchronized. In this way, various operations other than printing operations can be synchronized. However, there are problems such as the need to synchronize the latch operation in order to eliminate phase shifts caused by the power transmission system such as the clutch that transmits power between the gear train and the head. Furthermore, in this embodiment, the master and slave printers print at the same time using the timing signal from the master printer, but it is also possible to print by alternating the master and slave printers one dot at a time for reasons such as sharing one character generator. It will be done. As described above, according to the present invention, by adding a simple phase adjustment circuit,
The phases of the master and slave printers can be matched, and parallel printing of the master and slave printers can be performed at extremely low cost using a single control circuit.

The present invention can be applied not only to parallel control of printers but also to parallel control of various other devices.

[Brief Description of the Drawings] Fig. 1 is a perspective view of a schematic mechanism showing an embodiment of the present invention, a is a receipt journal printer which is a main printer, b is
is a slip printer which is a slave printer. Fig. 2 is a timing diagram showing an embodiment of the present invention, Fig. 3 is a circuit diagram of a phase adjustment circuit showing an embodiment of the invention, and Fig. 4 is a timing diagram showing the operation of the phase adjustment circuit shown in Fig. 3. It is a line diagram. 1 and 23 are print heads, 8 and 24 are motors,
16, 28 are reference signal generators, reed switches, G
H indicates the output of the phase adjustment circuit of the main printer, and H indicates the output of the phase adjustment circuit of the slave printer system.

Claims (1)

[Claims] 1. In a printing device that allows a main printer and a slave printer to print in parallel using one control circuit, a reference signal is provided in each of the master and slave printers and generates a signal before the start of printing in one print cycle as each drive motor rotates. Depending on the time difference between the signal from the generator and each reference signal generator, among the master and slave printers, the speed of the motor of the printer whose phase is leading is slowed down, or the speed of the motor of the printer whose phase is lagging is increased. 1. A printing device comprising a phase adjustment circuit that adjusts a motor drive signal of the printer so as to adjust the motor drive signal of the printer.