JPS62284762A - Printer - Google Patents

Abstract

PURPOSE:To prevent destruction and deterioration of a hammer solenoid and a power supply device by providing a configuration in which an energization command which is output from a control device is conveyed to a power supply device through an AC coupling circuit. CONSTITUTION:If an energization command is output by a control device 1, an AC coupling circuit 9 transmits an energization command to a power supply device 3. However, a control signal transmitted becomes an analog signal, and based on this control signal, a power is supplied to a hammer solenoid 2, hammering a type element 5 and printing a printing paper 8 through a ribbon 6. When an erroneous operation occurs on the control device 1, a control signal which is an input of the power supply device turns to a waveform whose potential increases due to the time constant of a condenser 10 and a resistor 11, if the energization command is output by the control device for an excessively long time. If the potential of a control signal reached a threshold value, the power supply device 3 stops current feeding to the hammer solenoid 2, thus preventing energization for an excessively long time. Consequently, the destruction and deterioration of a hammer solenoid and a power supply device can be prevented even when the control device malfunctions.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention Field of Industrial Application The present invention relates to a printing device using a hammer solenoid.

2. Description of the Related Art In recent years, hammer solenoids have come to be used in printing devices for printers and typewriters.

An example of the above-mentioned conventional printing device will be described below with reference to the drawings.

4, 6, and 6 show the structure and operation of a conventional printing device. In FIG. 4, 1 is a control device that outputs an energization command for a preset time, 2 is a hammer solenoid, and 3 is a power supply device that inputs the energization command and supplies power to the hammer solenoid 2. 4 is a type spoke, 5 is a type, 6 is a ribbon, 7 is a platen, and 8 is a printing paper.

The operation of the printing device configured as described above will be described below.

First, the control device 1 outputs an energization command as shown in FIG. 6V, and the power supply device 3 supplies a current as shown in FIG. 5 to the hammer solenoid 2 in accordance with the energization command. At this time, the hammer solenoid 2 strikes the type spoke 4 and prints the type 5 on the 8 print paper via the ribbon 6.

Problems to be Solved by the Invention However, with the above configuration, if the control circuit malfunctions, an excessively long energization command is output as shown in vl in FIG. Since the electric current shown in Fig. 6 is supplied, there is a problem in that the hammer solenoid 2 and the power supply device 3 deteriorate further and may even be destroyed.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to provide a printing device in which the hammer solenoid 2 and the power supply device 3 are not deteriorated or destroyed even if the control device 1 malfunctions.

Means for Solving the Problems In order to solve the above problems, the printing device of the present invention is provided with an AC coupling circuit, and the energization command output from the control device is sent to the power supply device via the AC coupling circuit. It is equipped with a structure that allows the information to be transmitted.

Effect of the Invention The present invention has the above-described configuration to prevent the AC coupling circuit from transmitting an energization command for an excessively long period of time to the power supply device even if the control device malfunctions. Since the hammer solenoid and the power supply device are not energized for a long period of time, destruction and deterioration of the hammer solenoid and the power supply device can be prevented.

EMBODIMENT A printing device according to an embodiment of the present invention will be briefly described below with reference to the drawings.

FIG. 1 shows a configuration diagram of a printing device in an embodiment of the present invention.
FIG. 2 shows operating waveforms during normal operation of the printing device in the embodiment of the present invention, and FIG. 3 shows operating waveforms when a malfunction occurs in the printing device in the embodiment of the present invention. In FIG. 1, the same parts as in the conventional example shown in FIG. 4 are given the same numbers, and the explanation will be omitted. 9 is an AC coupling circuit; the energization command that is the output of the control device 1 is transmitted to the power supply device 3 via the capacitor 10, and the input of the power supply device 3 is pulled up via the resistor 11. There is.

The operation of the printing apparatus configured as described above will be described below with reference to FIGS. 1, 2, and 3. First, normal operation will be explained. The control device 1 is
When the energization command, which is a digital signal as shown in FIG. The control signal transmitted to the power supply device 3 is an analog signal as shown by v5 in FIG. The power supply device 3 supplies the power as shown in FIG. I will do it.

Next, the operation when a malfunction occurs in the control device 1 will be explained. Due to the above malfunction, the control device 1
If the energization command is output for an excessively long time as shown in vl in the figure, charging of the capacitor 10 will start, so the control signal that is input to the power supply device #3 will be applied to the capacitor as shown in v3 in Fig. 10 and the time constant of the resistor 11 results in a waveform in which the potential increases. The power supply device 3 stops supplying current to the hammer solenoid 2 when the potential of the control signal reaches a threshold value. Therefore, even if the above-described malfunction occurs, the current supplied to the hammer solenoid 2 will be as shown at 1 in FIG. 3, thereby preventing the hammer solenoid 2 from being energized for an excessively long period of time.

As described above, according to this embodiment, the hammer solenoid 2
By providing the AC coupling circuit 9 for transmitting the energization command outputted from the 1h control device to the power supply device 3 that supplies power to the 1h control device, malfunctions may occur in the control device and the energization command may last for an excessively long time. Even in the event that the power is output, it is possible to prevent the destruction and deterioration of the non-nomaan renoids 2 and the power supply device 3.

In the first embodiment, the AC coupling circuit 9 is constructed of the capacitor 1o and the resistor 11, but the AC coupling circuit 8 may be constructed using other differentiating means.

Effects of the Invention As described above, the present invention provides an AC coupling circuit to ensure that the hammer solenoid and
Destruction and deterioration of the power supply device can be prevented. In other words, it is possible to realize a highly reliable printing device with a simple configuration at low cost, and its effects are industrially significant.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a printing device according to an embodiment of the present invention, Fig. 2 is an operating waveform diagram of the same device during normal operation, Fig. 3 is an operating waveform diagram during malfunction, and Fig. 4 is a conventional printing method. The configuration diagram of the device, Figure 6 is the operating waveform diagram during normal operation of the device, Figure 6
The figure is also an operational waveform diagram at the time of malfunction. 1... Control device, 2... Hammer solenoid, 3... Power supply device, 5... Typeface, 9... AC coupling circuit, 10... Capacitor, 11... Resistor. Name of agent: Patent attorney Toshio Nakao and one other person
Figure ゛Figure 3

Claims (2)

[Claims] (1) A typeface, a hammer solenoid that strikes the typeface, a power supply device that supplies power to the hammer solenoid, and a control device that outputs an energization command to supply power to the hammer solenoid for a preset time. and an AC coupling circuit for transmitting the energization command to the power supply device, wherein the AC coupling circuit has a low-frequency blocking characteristic in its transmission characteristic. (2) The printing device according to claim (1), wherein the AC coupling circuit is composed of a capacitor and a resistor.