JPH04369568A - Medium printer - Google Patents

Abstract

PURPOSE:To eliminate deterioration of a printing characteristic based on floating up of a medium from a platen under a ribbon mask. CONSTITUTION:In order to improve a printing characteristic by elastically pressing a medium 4 onto a platen 5 side, a ribbon mask 3 is elastically supported with a paper guide 2. Further, in order to prevent an edge part of the medium 4 from being folded since the edge part of the medium 4 collides with the ribbon mask 3 in line feed of a printing part, a gap between a printing head and the medium 4 is increased in line feed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a passbook printer, ie, a media printing device, for printing on passbooks used in banks, post offices, etc., and more particularly to an improvement in the ribbon mask of the media printing device.

0002

2. Description of the Related Art As shown in FIG. 5, in a conventional passbook printer 19, when the platen 5 approaches the print head 1 to print, a passage 14 between the paper guide 2 and the platen 5 is used. Passbook or medium 4 supplied within
The ribbon mask 3 is arranged between the ink ribbon 15 and the medium 4 so that the margin part thereof is not soiled by the ink ribbon 15, and is movable up and down within the area of the paper guide 2. This is because the distance between the head 1 and the platen 5 is small, and therefore the ribbon mask 3 cannot be properly positioned.

0003

[Problems to be Solved by the Invention] In such a known passbook printer 19, as shown in FIG. 5, the passbook often pushes up the ribbon mask 3 and floats on the platen 5 due to the repulsive force of the passbook. . For this reason, there is a problem in that a large amount of energy is received from the pins of the print head 1 when the bankbook is printed, and the quality of printing on the medium 4 is deteriorated.

0004

[Means for Solving the Problems] In order to solve the above problems, in the present invention, the ribbon mask 3 is elastically supported by the paper guide 2, and the medium 4 is pressed and held in the direction of the platen 5.

[0005]

[Operation] Since the ribbon mask 3 is elastically held by the paper guide 2, the ribbon mask 3 approaches the platen 5 side, and thus the ribbon mask 3 prevents the medium 4 from floating up.

[0006]

Embodiment FIG. 1 is a schematic diagram of a passbook printer 20 showing an embodiment of the present invention. In the following embodiments, the same members as in known printers will be described with the same reference numerals. In the printer 20 of the present invention, when the medium 4 is supplied between the print head 1 and the platen 5 by the roller 11 via the paper thickness detection section 6, the print head 1 is fed via the paper guide 2 and the ribbon mask 3. Print on this. Note that the symbols 7, 8, 9, 10, 11, and 12 are bearings, respectively.
These are an eccentric cam, pulley, PTS (paper thickness adjustment) motor, roller, and belt. Figure 2 is Figure 5 showing the printed part of the present invention.
This is a similar diagram. As is clear from FIG. 2, the other components are the same as the device shown in FIG. 5, except that the ribbon mask 3 is elastically held by the paper guide 2. The ribbon mask 3 is elastically held in the direction of the platen 5 by a spring member 16 whose one end is fixed to the paper guide 2 by a fastening member such as a small screw or a fixing member 21 (FIG. 3) such as an adhesive.

Therefore, even if the medium 4 has a repulsive force or is deformed, the medium 4 is forcibly and elastically pressed against the platen 5, and the entire surface of the medium comes into close contact with the platen 5. This pressing action thus reduces the energy loss that the medium 4 receives from the head pins of the print head, thereby improving print quality.

Further, by the ribbon mask 3 pressing the medium 4 against the platen 5 side, a sufficient gap is secured between the ribbon mask 3 and the print head 1. Therefore, friction against the ribbon between the print head and the ribbon mask is reduced, and excessive pulling out of the ink ribbon can be prevented.

[0009] By configuring the passbook printer in this manner, the passage between the paper guide 2 and the platen 5 becomes narrow, and in some cases, for example, when feeding the medium or when printing a new line, the edge of the medium may become a ribbon mask. 3, and thus there is a risk of damaging the edge.

This is because, in the conventional printing operation timing, as shown in FIG. 6, (1) the position of the platen 5 is changed by the PTS motor 10 to adjust the paper thickness according to the medium to be printed. As a result, the distance between the print head and the medium, which was initially 0.4 mm, is reduced to 0.27 mm.

(2) After adjusting the paper thickness, the carrier starts moving.

(3) When the carrier accelerates and then reaches a constant speed, printing starts.

(4) After printing is completed, the carrier starts decelerating.

(5) After the carrier stops, perform a line feed on the medium. During this line feed, the distance between the ribbon mask and the platen is the same as during printing.

If a known printing timing having such operation timing is used as is, in the present invention, in which the ribbon mask presses the medium against the platen side, the edge of the medium is pressed against the ribbon mask at line feed, etc. It is thought that there is an increased possibility of getting caught.

Therefore, in the present invention, the known operation timing which has the risk of causing such a drawback is solved by changing the timing as shown in FIG.

(a) The paper thickness of the medium 4 initially supplied into the passage 14 (FIG. 5) is measured by the roller section 11 immediately in front of the print head 1.
The paper thickness is detected by a paper thickness detection section 6 installed at

(b) In response to this detected value (paper thickness information), the PTS motor 10 rotates by the required amount. At this time, the carrier motor starts accelerating.

(c) The amount of rotation of the PTS motor 10 is transmitted to the pulley 9 by the belt 12.

(d) An eccentric cam 8 is coaxially mounted on the pulley 9, and this cam 8 engages with a bearing 7 mounted on the platen 5. Therefore, when the eccentric cam 8 rotates, the platen 5 moves in the vertical direction, and the distance between the ribbon mask 3 and the platen 5 can be adjusted. Based on the information from the paper thickness detection section 6, the motor 10 rotates the cam 8, and the cam 8 moves the platen 5 via the bearing 7, thereby increasing the distance between the ribbon mask 3 and the platen 5. Adjust the distance from print head 1 to media 4 to 0.
．． It is controlled so that it becomes 0.27mm from 4mm.

(e) The above platen adjustment in (d) is completed before the carrier passes through the acceleration period and reaches constant speed.

(f) After the carrier motor reaches a constant speed, printing is started.

(g) After printing is completed, the carrier motor starts decelerating. At this time, the PTS motor 10 lowers the platen 5 and increases the distance from the ribbon mask 3, increasing the distance between the print head and the medium to 0.4 mm.

(h) Carrier motor and PTS motor 1
When 0 stops, the media printing section starts changing operation by a known method. This changeover operation is performed when the distance between the print head and the medium is 0.27 mm as in the previous case shown in FIG.
However, in the case of the present invention, the distance is set to 0.4 mm.

(i) To continue printing on the medium 4, the operations (a) to (h) above are continued.

Thus, in the present invention, during printing, the gap between the printer head and the platen can be expanded using the automatic paper thickness adjustment mechanism at both ends of the medium. Therefore, problems such as damage to the media edges and clogging are eliminated.

[0027]

Effects of the Invention In the present invention, since the medium is pressed against the platen by a ribbon mask, lifting of the medium is reduced, loss of printing energy is reduced, and printing quality is improved. Furthermore, since a sufficient distance is secured between the ribbon mask and the print head, it is possible to eliminate failures in drawing out the ink ribbon due to friction of the print head. Furthermore, since the distance between the ribbon mask and the medium can be widened when the printing section passes the left and right ends of the medium, it is possible to prevent the edges of the medium from being bent by the ribbon mask, and furthermore, it is possible to prevent the ribbon mask itself from being deformed.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a printing device of the present invention.

FIG. 2 is a diagram showing a printing section of the present invention.

FIG. 3 is a diagram showing a state in which the ribbon mask of the present invention is supported by an elastic support member.

FIG. 4 is a diagram showing the printing operation timing of the present invention.

FIG. 5 is a diagram similar to FIG. 2 showing a printing section of a conventionally known printing device.

FIG. 6 is a diagram similar to FIG. 4 showing the printing timing of a conventionally known printing device.

[Explanation of symbols]

1 Print head 2 Paper guide 3 Ribbon mask 4 Medium 5 Platen 6 Paper thickness detection section 10 PTS motor 16 Elastic support member

Claims (2)

[Claims] 1. A print head 1, a platen 5, a paper guide 2 that holds a medium 4 between the platen 5, and a ribbon mask 3 that prevents the medium from being soiled by an ink ribbon 15 during printing. A medium printing device 20 having a printing section consisting of the following, characterized in that the ribbon mask 3 is elastically held toward the platen 5 by an elastic member 16 whose end portion is fixed to the paper guide 2. [Claim 2] While the platen is being moved upward to adjust the paper thickness, the carrier is moved at an accelerated pace, and when the carrier reaches a constant speed, the print head performs printing work, and after the printing work is completed, the platen is moved downward. Media printing that operates the media printing device according to claim 1, characterized in that the carrier is decelerated while moving, and the media printing is performed at a printing operation timing in which a line feed is performed on the printing part of the media after the platen movement is completed. How the device works.