JPH0582829B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an automatic paper thickness adjustment device that appropriately adjusts the distance between a platen and a printing head of a printing device according to the paper thickness of printing paper, and in particular, The present invention relates to an automatic paper thickness adjustment device for a print head that widens the gap when the paper jams.

[Prior art]

In wire dot printing devices, it is necessary to place the print head in close contact with the printing paper in order to print clearly. Conventionally, in order to make it possible to change the distance between the print head and the platen according to the paper thickness of the printing paper, an automatic paper thickness adjustment device has been provided that automatically moves and adjusts the print head.

Further, when the printing device receives a printing command, the printing head performs printing, and the paper feed roller executes sequence control associated with printing, such as feeding the printing paper. If the printing paper gets stuck inside the device during paper feeding and becomes combed or jammed (paper jam), a jam detection device usually detects the paper jam and automatically stops the operation of the printing device.

[Problem that the invention seeks to solve]

However, when removing the print paper that has caused a paper jam, the print head is in close contact with the print paper so as to have slip resistance due to the action of the automatic paper thickness adjustment device, so if the operator pulls it forcefully. There were problems such as the paper being torn, which took a long time to remove, and in some cases damaging the paper guide, ribbon mask, etc. attached to the tip of the print head.

This invention solves the above problem, and when a paper jam occurs, the driver of the automatic paper thickness adjustment device is used to move the print head away from the print paper, making it easier to remove the print paper. The purpose is to

[Means for solving problems]

The present invention provides a print head moving means in which the print head is movably associated with a drive body so that the distance between the print head and the platen can be changed, and the drive body in which the distance is adjustable in accordance with the paper thickness of printing paper. a paper thickness adjustment means for adjusting the paper thickness; a jam detection means for detecting a jam when the print paper is jammed during printing by the print head and outputting a jam signal; The present invention provides an automatic paper thickness adjustment device for a print head, comprising a jam control means for controlling a driving member so as to widen the interval adjusted by the adjustment means.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In FIG. 1, 1 is a wire dot type printing head, which is supported by a carrier frame 2 and slidably supported by a main shaft 4 arranged perpendicular to the paper feeding direction of printing paper 3. has been done. A support shaft 5a of a gear 5 is eccentrically fixed to one end of the main shaft 4.
and the gear 7 of the stepping motor 6 for paper thickness adjustment. The stepping motor 6 is at its initial position when the tip of the head is at the farthest position from the platen. Therefore, the rotation of the gear 7 causes the main shaft 4 to rotate eccentrically, and the print head 1 is moved so that the distance between the leading edge printing portion 1a and the flat platen 8 can be changed. Note that an ink ribbon 9, a ribbon mask 10, and a paper guide 11 are placed between the printing paper 3 and the printing paper 3 at the tip of the printing section 1a.
(Both ends are omitted from the drawing) are mounted on the carrier frame 2 so that they are arranged. Also, gear 5
The shaft 5a and the stepping motor (driver) 6 are supported by a machine frame (not shown), and the main shaft 4
The other end is eccentrically rotatably supported by the machine frame.
The print head 1, carrier frame 2, main shaft 4, gears 5, 7, and motor 6 constitute print head moving means.

Reference numeral 12 denotes a jam sensor 12, which is arranged in the machine frame from the flat platen 8 in the paper feeding direction and detects the passage of the printing paper 3.It is a jam sensor 12 that detects the passage of the printing paper 3 even though it is being printed. ,
It is detected in conjunction with a timer, which will be described later, and generates a jam signal, and constitutes a jam detection means.

Next, a circuit for controlling the above mechanism will be explained based on the block diagram shown in FIG.

As the print paper detection function of the jam sensor 12, it detects the print paper 3 and when it does not detect it.
By inputting an ON signal and an OFF signal to the CPU 13, the ROM 14 supplies the stored program to the CPU 13, controls the driver 15 of the printing head moving means, and adjusts the stepping motor 6 for adjusting paper thickness. A paper thickness adjusting means is configured.

Also, when the print signal 16 is input to the CPU 13, the ROM 14 transfers the program to the CPU 13.
The RAM 17 stores the print signal 16,
The printing head 18 prints, the paper feed motor 19 feeds the printing paper 3, and the carrier motor 20 constitutes a printing means for executing a printing sequence in which the printing head 1 is transported in the printing direction.

Furthermore, the CPU 13 is detected by the above-mentioned jam detection means.
When the printer detects a jam in the printing paper 3 according to the program stored in the ROM 14, the jam display 21 displays a jam to the operator, the printing sequence is stopped, and the driver 15 of the printing head moving means is controlled. A jam control means for adjusting the stepping motor 6 is configured.

Next, the operation of the printing device will be explained based on the flowchart shown in FIG.

A printing paper 3 is interposed between the printing head 1 and the flat platen 8, and a jam sensor (paper sensor)
12 detects the printing paper 3 and turns ON, first, automatic paper thickness adjustment is performed. In other words, the CPU 13 is a ROM
14, the paper thickness adjusting stepping motor 6 is driven from the initial position by the driver 15, the main shaft 4 is rotated counterclockwise in the figure, and the print head 1 is lowered. When the printing section 1a comes into contact with the printing paper 3 and the motor 6 goes out of step, the motor 6 is reversed and the printing section 1a is moved from the printing paper 3 by approximately 0.1 in sequence.
Raise mm and stop. In this state, even though the paper is being fed for printing, there is strong sliding resistance, and if the printing paper is pulled too hard, there is a possibility that it will tear.

When the print signal 16 is input to this CPU 13,
The printing device operates and printing is performed as follows. That is, according to the program stored in the ROM 14, print data is stored in the RAM 17,
The printing head 18 presses the ink ribbon 9 against the printing paper 3 as appropriate to print, the carrier motor 20 moves the printing head 18 in the printing direction to execute the printing sequence, and the paper feed motor 19
is used to feed the printing paper 3 to change lines of printing or to eject the printing paper 3.

If the printing paper 3 is not ejected even after completing the paper feeding operation required for normal paper feeding, and the jam sensor 12 continues to detect the printing paper 3, there is a paper jam (paper jam) in the printing device. The CPU 13 transfers the print data to the RAM.
17 to stop printing and display a jam to the operator.

Furthermore, the CPU 13 operates the driver 15 and drives the paper thickness adjustment motor 6 to eccentrically rotate the main shaft 4 clockwise in FIG.
Set print head 1 to its initial position, which is the maximum elevation of 0.8 mm.
move it upwards.

By releasing the paper press roller (not shown), the operator can easily pull out the jammed printing paper 3 from between the printing head 1 and the flat platen 8.

The CPU 13 transfers the new printing paper 3 to the print head 1.
When installed between the paper platen 8 and the flat platen 8, the paper thickness adjustment is performed and printing is resumed.

〔Effect of the invention〕

The structure and operation of the present invention are as described above, and when the print paper jams, the print head in contact with the print paper is automatically raised, making it easy to pull out and remove the paper. Ta.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention, FIG. 2 is a control block diagram, and FIG. 3 is a flowchart. 1...Print head, 6...Paper thickness adjustment motor (driver).

Claims (1)

[Scope of Claims] 1. A print head moving means in which the print head is movably associated with a drive body so that the distance between the print head and the platen can be changed, and the distance can be adjusted according to the paper thickness of the printing paper. a paper thickness adjusting means for adjusting the driving body; a jam detecting means for detecting a jam when the print paper is jammed during printing by the print head and outputting a jam signal; and a jam detecting means for receiving the jam signal. an automatic paper thickness adjustment device for a print head, comprising: a jam control means for controlling a drive body so as to widen the interval adjusted by the paper thickness adjustment means.