JPH0357651A - Ink jet printer - Google Patents

Abstract

PURPOSE:To absorb temporarily generated noise or abnormal voltage when a power supply is turned ON/OFF and thereby prevent a drive signal from being connected to a head as it is by providing a disconnector which disconnects a head drive signal in a head drive circuit. CONSTITUTION:A head drive signal (c) is connected to a head 1 from a drive control part 3 through a disconnector 2. In the meantime, the disconnector 2 is controlled by a disconnector control signal (d) from a mechanism control part 4. In addition, an interface part 5 is connected to an area between the mechanism control part 4 and a drive control part 3. In this ink jet printer, the disconnector 2 is set in 'OFF' position when the power supply is turned ON, and an initial noise generated at that time does not reach the head 1. Next, after the lapse of adequate time required for the initial noise to disappear since the turning ON of the power supply, the disconnector is turned ON by an issued disconnector control signal (d). Consequently, data output is enabled. The mentioned autopower ON process is run when the power supply is shut off, and a disconnection control process is added to the end of the process. Thus turning the power supply ON/OFF is enabled without supplying an abnor mal signal and an abnormal voltage to the head 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inkjet printer, and more particularly to an inkjet printer using an electrical-mechanical energy conversion element as a driving source.

[Conventional technology]

In recent years, with the development of office automation, printers used in offices are expected to print silently and output characters and images at high speed and with high quality. In particular, the above-mentioned inkjet printers use many heads that eject ink droplets using an electro-mechanical energy conversion element as a driving source. Further, the output is performed by applying an electrical pulse to the head.

FIG. 2 is a schematic diagram of the main mechanical parts of an inkjet printer showing an example of a conventional printer.

As shown in FIG. 2, such a printer includes a platen 11
A carrier 7 is provided so as to be slidable on a guide shaft 8 disposed parallel to the output paper 12 wound around the paper. A head 1 to which an ink supply tube 10 and a signal cable 9 are connected is mounted on the carrier 7, and the head 1 is fixed so as to face the output paper 12. Therefore, when printing, carrier 7
Printing is performed by sliding the head 1 and applying a drive pulse to the head 1 in synchronization with the sliding timing.

In addition, a cap mechanism 13 is provided at the home position of the head [-] mounted on the carrier 7 to prevent the head from drying out during storage and movement of the apparatus. Here, when turning off the power of the apparatus, it is necessary to perform a capping operation to protect the head. Therefore, after the operator turns the power switch to the OFF side, the capping sequence is automatically executed. That is, an auto power-off system is adopted in which the power is turned off only after the head 1 is placed in a protected state.

[Problem to be solved by the invention]

In the conventional inkjet printers mentioned above, the drive signal control unit is directly connected to the head, so noise and abnormal voltage that occur temporarily when the power is turned on and off are directly transmitted to the head, which has a negative impact on the head. There is.

An object of the present invention is to provide an inkjet printer that absorbs noise and abnormal voltage temporarily generated when the power is turned on and off, and does not directly transmit it to the head.

[Means for Solving the Problems] The Inkjet I printer of the present invention is an inkjet printer that uses an electro-mechanical energy conversion element as a drive source, and is equipped with a circuit breaker that cuts off a head drive signal in the head drive circuit. be done.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a circuit block diagram of an inkjet printer showing one embodiment of the present invention.

As shown in FIG. 1, in this embodiment, power is supplied from a power source 6 to the mechanism control section 4 via the power line a, and also to the drive control section 3 via the power line b. The head drive signal C from the drive control section 3 is sent to the head 1 via the circuit breaker 2. On the other hand, the circuit breaker 2 is controlled by a circuit breaker control signal d from the mechanism control section 4. Further, an interface section 5 is connected between the mechanism control section 4 and the drive control section 3.

In such an inkjet printer, the circuit breaker 2 is turned off when the power is turned on, and the initial noise generated at that time does not reach the head 1. Next, after a sufficient period of time has elapsed since the power was turned on for the initial noise to disappear, the circuit breaker control signal d is sent to turn it on. As a result, output becomes possible. Furthermore, when the power is turned off, the above-mentioned auto power-off process is executed, and a cut-off control process is added at the end. As a result, after cutting off between the drive control section 3 and the head 1, the power of the apparatus is turned off.

With the above configuration, power can be turned on and off without supplying an abnormal signal and abnormal voltage to the head 1.

〔Effect of the invention〕

As described above, the inkjet printer of the present invention has the advantage that by connecting a circuit breaker to a conventional device configuration, it is possible to completely eliminate the cause of output failures that occur when power is turned on and off. Furthermore, the present invention has the effect that when power is turned off, only a change in the firmware that adds several steps to the conventional power-off sequence is required, so that the burden placed on the firmware of the device as a whole is not too large.

[Brief explanation of drawings]

FIG. 1 is a circuit block diagram of an inkjet printer showing an embodiment of the present invention, and FIG. 2 is a schematic diagram of the main mechanical parts of an inkjet printer showing a conventional example. DESCRIPTION OF SYMBOLS 1... Head, 2... Circuit breaker, 3... Drive control part, 4... Mechanism control part, 5...
・Interface part, 6...Power supply.

Claims (1)

[Claims] An inkjet printer using an electro-mechanical energy conversion element as a drive source, characterized in that a head drive circuit is provided with a circuit breaker that cuts off a head drive signal.