JPH0230570A - Printing device - Google Patents

Abstract

PURPOSE:To make possible the smooth paper feed by allowing an intermediate paper guide to rock and rotate upward in response to the opening/closing action of a paper holder and arranging said guide so that it reaches a paper feed tractor wheel and a platen across the entire width of paper. CONSTITUTION:If a paper holder 18 is set to an open state for paper 12 attachment, an intermediate paper guide 19 which is lightly kept in contact with the paper holder 18 rotates upward, contering around a shaft supporting hole 20 as a fulcrum together with the paper holder 18. If the paper holder 18 is set to a closed state after paper attachment, the paper guide 19 rotates downward by tensile strength of a coil spring 21, returning to its original state. The paper guide 19 rotates vertically following the opening/closing action of the paper holder 18 as described above. Therefore, the paper 12 can be held across the entire space between a paper feed tractor wheel 11 and a platen 13. In addition, the entire paper width can be held constantly regardless of paper width. Thus, the sagging of the paper 12 is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a printing device equipped with a paper feeding mechanism in which recording paper is fed into a printing section by a tractor.

2. Description of the Related Art Conventionally, this type of printing apparatus has had a paper feeding mechanism as shown in FIG. In Fig. 3, 1 is a paper feed retractor, and paper 2 is placed on the surface of a belt passed between two pulleys.
A tractor claw 1a that engages with a hole provided in the edge of the paper protrudes at a predetermined interval, and the tractor claw 1a is moved by rotation of a tractor drive shaft 1b directly connected to one of the pulleys to print on the paper 2. I am sending it to the department. A platen 3 around which the paper 2 is wound rotates in synchronization with the tractor drive shaft 1b. 4 is an introduction guide member that guides the paper 2 fed into the paper feeder 2 to the platen 3; 5 is mounted on a carrier 6 that faces the platen 3 and is moved parallel to the platen 3 by a motor; The print head is

Further, 7 is a paper pressing roller that presses the paper 2 against the platen 3. Reference numeral 8 denotes a paper press plate supported by the tractor section for fitting the paper 2 into the tractor claw 1a.

In the above configuration, the paper 2 is fed by the paper feed tractor 1, guided by the introduction guide member 4, and wound around the platen 3. Then, after printing is performed by the print head 5 using the platen 3 as a printing stand, the paper is fed out from between the paper pressing roller 6 and the platen 3.

Problems to be Solved by the Invention However, in this conventional configuration, the paper presser plate 8 is
It is necessary to open the paper 2 when inserting the paper 2. Since the paper feed mechanism 1 is close to the platen 3, the dimensions on the platen side are restricted. This creates a space between the paper feed tractor 1 and the platen 3. For this reason, in the conventional example above, when continuous paper with perforations is used,
Due to processing accuracy of the platen diameter, expansion/contraction of the platen diameter due to temperature changes, and contact frictional resistance with the guide member 4 for introduction, etc., the difference between the amount fed by the paper feed H-tractor 1 and the platen 3 may vary. This causes a difference in the amount delivered.

When the platen diameter is large and the amount of paper 2 wrapped around the platen 3 and sent out is larger than the amount of paper 2 sent by the paper feed tractor 1, the paper 2 is held by the tractor section and the paper 2 is held on the platen 3. is in a slip state,
Although it is not a big problem, when the platen diameter is small and the amount of paper 2 fed by the paper feed retractor 1 increases, the paper 2 may sag in the space between the paper feed retractor 1 and the platen 3. If this condition were to continue, the paper 2 would become jammed, making it impossible to print, and even causing a malfunction of the printing device.

The present invention aims to eliminate these conventional drawbacks and provide a printing device that can smoothly feed paper.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a paper feed tractor that feeds the paper while holding it with a paper presser plate, a platen, a guide member provided along the outer periphery of the platen, An intermediate paper guide is provided on the paper travel path between the paper feed tractor and the platen, and the intermediate paper guide is capable of swinging upward in accordance with the opening/closing operation of the paper presser plate. The intermediate paper guide is arranged so as to extend over the entire area of the paper sheet and to the paper transport tractor and platen.

Effects According to the above structure, the intermediate paper guide moves up and down when the paper holding plate is opened and closed, so the intermediate paper guide does not become an obstruction when paper is loaded, so the intermediate paper guide can be placed near the paper holding plate. This prevents paper from sagging and bulging.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 and 2.

Reference numeral 11 denotes a paper feed tractor; a bell 11e passed between two pulleys 11C and 111d has tractor claws 11a protruding at predetermined intervals to engage with holes provided at the edge of the paper 12; The tractor claw 11a is moved by the rotation of a tractor drive shaft 11b directly connected to the paper 12, thereby feeding the paper 12 into the printing section. A platen 13 around which the paper 12 is wound rotates in synchronization with the tractor drive shaft 11b. Reference numeral 14 denotes an introduction guide member that guides the paper 12 fed by the paper feeder 11 to the platen 13, and 15 a print head mounted on a carrier 16 that faces the platen 13 and is moved parallel to the platen 13 by a motor. , 17 is a paper press roller that presses the paper 12 against the platen 13, and 18 is a tractor claw 11a that presses the paper 12 against the platen 13.
A paper holding plate 19 supported by a tractor unit to be fitted into the paper guide is an intermediate paper guide according to the present invention, and pillars fixed to the left and right side plates are inserted into bearing holes 20 provided on both end faces. In this state, a coil spring 21 attached to the paper traveling path between the paper feed tractor 11 and the platen 13 and further attached near the end face causes the paper holding plate 18 to
is being pressed down with a light force.

In this configuration, when the paper presser plate 18 is opened to load the paper 12, the intermediate paper guide 19, which is in light contact with the paper presser plate 18, moves up with the paper presser plate 18 around the bearing hole 20, which is a fulcrum. After the paper is loaded, the paper presser plate 18 is rotated downward and returned to its original state by the tensile force of the coil spring 21 and 7A-, which closes the paper press plate 18. As described above, since the paper holding plate 18 can be rotated vertically in accordance with the opening/closing operation, it is possible to hold the paper 12 over the entire space between the paper transport tractor 11 and the platen 13, and regardless of the size of the paper. The entire inside of the paper can be pressed at all times, and walnuts in the paper 12 can be eliminated.

The present invention has a configuration that exceeds the effects of the invention.By preventing paper from curling and bulging, stable paper feeding can be realized in any temperature atmosphere, and it can be highly reliable, making it suitable for industrial use. It is of great value.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a main part of a printing device according to an embodiment of the present invention, FIG. 2 is an explanatory cross-sectional view of the same, and FIG. 3 is an explanatory cross-sectional view of a conventional printing device. 11...Paper feed tractor, 12...Paper, 1
3...Platen, 14...Introduction guide member,
15...Print head, 16...Carrier, 1
7...Paper press roller, 18...Paper press plate, 19...Intermediate paper guide. Name of agent: Patent attorney Shigetaka Awano and one other person

Claims (2)

[Claims] (1) A tractor that feeds the printing paper while holding it with a paper holding plate, a platen, a guide member provided along the outer periphery of the platen, and an intermediate paper provided in the paper travel path between the tractor and the platen. A printing device comprising a guide, and a mechanism in which the intermediate paper guide can swing and rotate upward in response to opening/closing operations of the paper presser plate. (2) The printing device according to claim 1, wherein the intermediate paper guide is arranged to extend over the tractor and the platen.