JPS5851003Y2 - Printing error detection device for printing equipment - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a device for detecting printing errors in a printing device.

In general, there are printing devices as shown in FIGS. 1 and 2.

Reference numeral 1 denotes a printing shaft, and on its outer surface, as shown in FIG.
are attached to correspond to each digit in the length direction of the printing shaft 1, and rotate in the direction of arrow A.

A hammer 2 is positioned on the same horizontal line along the length direction of the printing shaft 1 so as to correspond to each printing band 1a.

Reference numeral 3 denotes a counting signal generating plate, which has the same cross-sectional shape as the printing shaft 1, and the outer periphery of the counting signal generating plate 3 has the markings 1 to 1 of the printing shaft 1.
A detected object 4 is attached to correspond to 9 and rotates in synchronization with the printing shaft 1.

A magnetic detector 5 is installed on the same horizontal line as the hammer 2 and detects the passage of the object 4 to be detected.

Reference numeral 6 denotes a reset pulse signal generation plate, which has the same shape as the count signal generation plate 3, and has a detected object 7 attached to its outer periphery so as to correspond to the print O on the printing axis 1, and is synchronized with the printing axis 1. It's rotating.

8 is also a magnetic detector, which is mounted on the same horizontal line as the hammer 2 and detects the object 7 to be detected.

9 shown in FIG. 2 is a counting pulse generator, and a magnetic detector 6
A counting pulse is generated based on the detection result.

A reset pulse generator 10 generates a reset pulse based on the detection result of the magnetic detector 8.

This reset pulse rises when the magnetic detector 8 detects the rotational direction side end 7a of the detected object 7, and
It rises when the opposite end of is detected, and occurs every time the printed numeral O of each printing band 1a rotates once and passes the position of the hammer 2.

A counter 11 is reset when the reset pulse falls, and then counts the counting pulses.

Therefore, this count value matches the value printed at the position of each hammer 2.

A print data storage device 12 stores data to be printed in each digit.

Reference numeral 13 denotes a controller that compares the count value of the counter 11 with the print data, and when they match, drives the hammer 2 of the matching digit via the driver 14 to print.

In such a printing device, malfunction of the counter 11 itself due to noise etc., failure of the pulse generators 9 and 10, and failure of the detectors 5,
8, the counted value of the counter 11 and the print at the position of each hammer 2 no longer correspond to each other, resulting in a problem of erroneous printing.

The object of this invention is to provide a printing error detection device for a printing device that solves the above-mentioned problems.

This invention will be explained below based on an embodiment shown in FIG.

The printing device shown in FIG. 3 is the same as that shown in FIGS. 1 and 2, and the same parts are designated by the same reference numerals.

In the figure, the part surrounded by dotted lines is a printing error detection device.

Reference numeral 15 denotes a reference value setting device which stores a printed number O that generates a reset signal when passing the position of the hammer 2, that is, a number 9 corresponding to the printed number 9 immediately before the last printing.

A gate circuit 17 inputs the count value of the counter 11 to the matching circuit 16 during the period when the reset pulse is generated, that is, from the rising edge to the falling edge of the reset pulse.

The coincidence circuit 16 compares the count value of the counter 11 supplied via the gate circuit 17 and the reference value of the reference value setter 15 when the reset pulse rises, and if the two do not match, Generates an error signal when the reset pulse falls.

Next, the operation will be explained.

Assume that the gate circuit 17 is now closed.

In this state, it is assumed that the printed number 0 on each printing band 1a of the printing shaft 1 reaches the position of each hammer 2, and a reset pulse is generated.

The counter 11 is reset by the fall of this reset pulse, and its count value becomes O.

Thereafter, the printing shaft 1 rotates and the counter 11 counts the detection signal generated by the detection pulse generator 9 every time the printed numeral on each printing strip 1a reaches the position of each hammer 2.

Then, when the printing shaft 1 rotates once and the printed number 0 reaches the position of each hammer 2 again and the reset pulse rises, the gate circuit 17 opens and the counted value of the counter 11 changes to the matching circuit 16.
The counted value of the counter 11 and the reference value of the reference value set value 15 are compared.

Here, if the printing device does not have the above-mentioned malfunction and there is no printing error, the counter 11 is reset when the printed number is 0, and then the detection signal generated as the printing number wraps around the position of each hammer 2. , the counted value is 9.

Therefore, since the count value and the reference value match, no error signal is generated when the reset pulse falls.

However, if there is a failure as described above, the two do not match, and the matching circuit 16 generates an error signal when the reset signal falls, indicating that a printing error has occurred.

As described above, in the printing error detection device according to this invention, the counted value of the counter 11 corresponding to the printed digit one before the actual final printed digit and the counted value one before the final printed digit that should be A matching circuit 16 compares the printed numerals with the reference value setter 15 when the reset signal rises, and generates an error signal when they do not match.

Therefore, if the value of the counter 11 does not correspond to the print at the position of the hammer 2 due to the above-mentioned causes, and the print is erroneously printed, this can be detected.

Moreover, this erroneous printing detection uses the count value and reset signal obtained from the counter and reset signal generator, which are always provided in a normal printing device, and the gate circuit 1
By simply adding 7, the reference value setter 15, and the coincidence circuit 16, a printing error detection device can be easily constructed.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a printing shaft, count signal generation plate, and reset signal generation plate of a conventional printing device, Fig. 2 is a block diagram of a conventional printing device, and Fig. 3 shows a printing error detection device according to this invention. FIG. 2 is a block diagram of a printing device according to the present invention. 1...Printing shaft, 1a...Printing band, 2.
... Hammer 9 ... Counting pulse generator,
10... Signal generator, 11... Counter, 12... Print data storage device, 13...
・Controller, 15...Reference value setting device, 16...
...matching circuit.

Claims (1)

[Scope of utility model registration request] It is a cylindrical body and has a printing band in which printing from the first printing to the final printing is arranged in order along its outer circumference, and a printing shaft that rotates in a predetermined direction, and a printing belt that is provided along the length of this printing shaft. a counting panel generator that emits a counting pulse every time a printing other than the final printing of the printing band comes to the hammer position; a signal generator that emits a reset signal that falls when the trailing edge of the final print passes the hammer position; a counter that is reset by the rising edge of the reset signal and that counts the counting pulse; and a counter that stores print data. In a printing device comprising a print data storage device and a controller that compares the print data with the count value of the counter and drives a hammer when they match; corresponding to the print immediately before the last print on the print shaft. a reference value setting section that stores count values, and a circuit that compares the value of the reference value setting section and the value of the counter when the reset signal rises, and generates an error signal when they differ. A printing error detection device for a printing device comprising: