JPH01195085A - Printer - Google Patents

Abstract

PURPOSE:To render a head gap appropriate and contrive higher reliability, by separating a printing head from a platen roller at the time of insertion of a paper, and thereafter controlling the gap between the tip of the head and the paper based on thickness data on the paper obtained by a detecting means. CONSTITUTION:At the time of detecting the thickness of a paper 30, a bial roller 22 is returned from a reference position I to a position H. In this case, step pulses are obtained through slit parts 27 of a detecting plate 26 turned in a recessed part of a sensor 28. Therefore, the thickness of the paper 30 is detected based on the difference between the angle (m) between positions I and G of the bail roller 22 and the angle (o) between positions I and H of the roller 22. Next, a central controlling part 42 drives a gap motor 38 based on the result of detection by the sensor 28 and data stored in a memory 43, thereby moving a printing head 41 to an appropriate position. Thereafter, the head 41 starts printing on the paper 30.

Description

[Detailed description of the invention] [Object of the invention 1 (Industrial application field) The present invention relates to a printing device.

(Prior art) In recent years, the content output from a computer is printed using a mechanical mechanism, such as Inbaku! Printers using the 1-to-1 method are popular (hereinafter referred to as 1-printers)
.

By the way, when printing with an impact printer,
The position of the print head is adjusted according to the thickness of the printing paper.

FIG. 6 shows the above-mentioned Invac 1-printer.

As shown in the figure, the impact printer includes a platen roller 1 that serves as a backing for the paper during printing, a bail roller 2 that suppresses the floating of the paper from the platen roller 1.
2. To the pale shirt 1 where each bail roller 2 is attached 3.
A rotatable bail arm 4 that supports the bail shaft 3 is provided. The impact printer also includes a shaft 6 whose both ends are supported on a different axis by a chassis 5.5 via a power arm (not shown), a print head 7 that moves along this shaft 6, and a platen roller 1. An operating lever 8 is provided that is operated to adjust the gap between the set paper and the tip of the print head 7.

As shown in FIG. 7, when adjusting the gap between the sheet of paper inserted along the platen roller 1 and the tip of the print head 7, the adjustment lever 8 is moved as shown in the arrow in order to obtain the desired gap. Rotated in direction a or b. At this time, when the shaft 6 rotates in the direction of arrow a, the central axis is displaced and the print head 7 mounted on the carriage 10 separates from the platen roller 1. In addition, numeral 11 in the figure indicates the above-mentioned cam.

<Problems to be Solved by the Invention> However, in the above-mentioned impact printer, if the adjustment lever 8 is not properly adjusted, for example, if the tip of the print head 7 comes too close to the paper 9, the print head 7 There are problems such as damage to the paper 9 caused by the leading edge contacting the paper 9, improper paper feeding, or damage to the print head 7 caused by the leading edge of the print head 7 getting caught in the paper 9.

In view of the above-mentioned problems, the present invention aims to provide a printing device that can reliably and appropriately maintain the gap between the paper and the tip of the print head.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a platen roller that serves as a backing for paper during printing, and a pale shirt 1-
A bail roller that suppresses the floating of the paper from the platen roller attached to the platen roller, a rotatable support arm that supports the pale shirt 1 to 1, and a rotatable support arm that supports the pale shirt 1~, and the rotation of the support arm that suppresses the floating of the paper between the bail roller and the platen roller. A detection means for detecting the thickness, a shaft that rotates eccentrically with both ends supported on different axes, a print head mounted on a carriage that moves along this shaft, and a print head that is mounted on a carriage that moves along this shaft. The present invention is characterized by comprising a control means for separating the print head from the platen roller and then controlling the amount of gap between the tip of the print head and the paper based on information on the thickness of the paper from the detection means.

(Function) In the present invention, when paper is inserted, the print head is separated from the platen roller, and then the amount of gap between the tip of the print head and the paper is controlled based on the paper thickness information obtained by the detection means. Therefore, the gap between the paper and the tip of the print head is reliably and appropriately maintained.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a paper thickness detection v1 ellipse for detecting the thickness of paper in an impact printer.

As shown in the figure, the paper thickness sensor a is provided with a pale gear 21 and a pale arm (not shown) that are attached to one end of a shaft and have a rotational fulcrum 20 as the fulcrum, which will be described later. Furthermore, a bail roller 22 attached to the pale shirt 1- (not shown) is provided at the end of the bail arm.

Further, the paper thickness detection mechanism includes a large transmission gear 24 having a transmission gear 23 that meshes with the pale gear 21, and a paper detection plate 26 that has a sensor gear 25 that meshes with the large transmission gear 24.
is provided. Further, a slit portion 27.27 is provided at the end of the paper detection plate 26, and this end is approximately U
Four parts of the detection sensor 28 formed in a letter shape (not shown)
is inserted into.

In addition, in the figure, 29 indicates a platen roller, and 30 indicates a sheet of paper.

Then, when the shaft rotates, along with this rotational movement,
The bail roller 22 moves towards and away from the platen roller via the pail arm and the bail shaft. Further, as the shaft rotates, the paper detection plate 26 is rotated in the direction of arrow C or d via the transmission gear 23 and the large transmission gear 24.

FIG. 2 shows a gap adjustment mechanism that adjusts the gap between the tip of the print head and the paper.

As shown in the figure, gap adjustment I! Shirt 31 on the oval
A protrusion 32 is provided on a part of the circumferential surface that is attached to the other end in a non-axial manner.
A cam 33 having a cam 33 and a cam gear 34 attached to the cam 33 are provided. Further, this gap adjustment mechanism is provided with a large speed change gear 36 having a small speed change gear 35 that meshes with the cam gear 34. Further, the gap adjustment mechanism is provided with a gap motor 38 having a pinion 37 that meshes with a large variable speed gear 36.

In the figure, numeral 39 indicates a protruding portion protruding from a chassis (not shown), numeral 40 indicates a carriage that slides in the axial direction of the shaft 31, and numeral 41 indicates a print head mounted on this carriage 40, respectively.

The driving force of the gap motor 38 is the pinion 37
, transmission gear 35, large transmission gear 36, cam gear 34, and cam 33 to the shirt 1-31. At this time, when the shaft 31 rotates in the direction of the arrow e or f, the center axis A of the shirts 1 to 31 is displaced from the center axis B of the cam 33, so that the print head 41 is rotated in the direction of the arrow g or h.
It is designed to move in the direction. In addition, the shaft 31
The cam 33 can be rotated in the direction of arrow e until the protrusion 32 of the cam 33 comes into contact with a protrusion 39 provided on the chassis.

FIG. 3 shows the main configuration of a control section that controls the operation of the above-mentioned impact printer.

As shown in the figure, the control unit includes a central control unit 42 that controls the operation of each component to be described later, a paper 30, and a print head 4.
1, a drive circuit 44, a gap motor 38, a sensor interface 45, and a detection sensor 28.

Then, the detection sensor 28 detects the movement of the bail roller 22 toward and away from the platen roller 29 when the paper is inserted, and based on this detection result and information stored in the memory 43, the central control unit 42 controls the drive circuit. The gap motor 38 is driven via the motor 44.

Next, the operation of the impact printer described above will be explained using FIGS. 4 and 5.

First, immediately after turning on the impact printer,
Since the gap between the print head 41 and the platen roller 29 and the position of the detection sensor 28 and the detection plate 26 may change, the reference positions of the detection sensor 28 and the detection plate 26 are set. This reference position is a position where the shaft 31 is rotated in the direction of the arrow e by, for example, the driving force of the gap motor 38, and the protrusion 32 of the cam 33 comes into contact with the protrusion 39 provided on the chassis. At this time, the bail roller 22 is at the position shown in the figure.

Next, when detecting the thickness of the paper 30, the bail roller 22 is returned to the position H in the figure. At this time, a step pulse of the slit portion 27 of the detection plate 26 rotating within the recess of the detection sensor 28 is obtained.

Therefore, the angle m of the position iI~G of the bail roller 22 and ■~
The thickness of the paper 30 is detected based on the difference between the angle H and the angle Q.

Next, the central control unit 42 drives the gap motor 38 based on the detection result of the detection sensor 28 and the information stored in the memory 43 to move the print head 41 in the direction of arrow g.

Thereafter, the print head 41 starts printing on the paper 30.

Therefore, in this embodiment, the amount of gap between the tip of the print head 41 and the paper 30 is appropriately adjusted based on the detection result of the detection sensor 28 and the information stored in the memory 43.

[Effects of the Invention] As described above, the printing device of the present invention can reliably and appropriately maintain the gap between the paper and the tip of the print head.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a detection mechanism of an impact printer according to an embodiment of the present invention, FIG. 2 is a diagram showing a gap adjustment mechanism of FIG. 1, and FIG. 3 is a configuration of a control section of the impact printer of FIG. 1. FIG. 4 is a flow chart showing the operation of the impact printer shown in FIG. 1, FIG. 5 is a diagram showing the operation of FIG. 1, FIG. 6 is a perspective view showing the conventional impact printer, and FIG. 6 is a diagram showing the gap adjustment mechanism of FIG. 6. FIG. 22...Bail roller, 26...Paper detection plate, 27
...Slit part, 28...Detection sensor, 29...
Platen roller, 30... Paper, 31... Shaft, 33... Cam, 38... Gap motor, 4o.
... Carriage, 41... Print head, 42... Central control unit, 43... Memory. Applicant: Toshiba Corporation Patent Attorney Sasa Suyama - Figure 1 O Figure 2 Figure 3 Figure 4 Figure 5 Prefecture

Claims (1)

[Claims] a platen roller that serves as a backing for the paper during printing; a bail roller that suppresses floating of the paper from the platen roller attached to a bail shaft; a rotatable support arm that supports the bail shaft; a detecting means for detecting the thickness of the paper between the bail roller and the platen roller as the support arm rotates; a shaft whose both ends are supported on different axes and rotates eccentrically; The print head is mounted on a moving carriage, and when the paper is inserted, the print head is separated from the platen roller, and then the tip of the print head is separated from the platen roller based on the paper thickness information from the detection means. A printing device comprising: a control means for controlling a gap amount between the paper and the paper.