JPH0615248B2 - Printer - Google Patents

Description

Detailed Description of the Invention A. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus that can use both long printing paper having a feed hole on its side edge (so-called continuous paper) and short printing paper having no feed hole (so-called cut-form or single-sided paper). is there. This printing device is characterized by the relationship of the sheet feeding path with respect to the platen and the retractable structure of the continuous sheet feeding means.

B. Prior Art (Fig. 2) Japanese Patent Application Laid-Open No. 57-38175 relates to a feeding device capable of using continuous paper and single-piece paper, but since the platen is of a roller type, a linear paper feeding path is provided. Don't give.

Although flat plate type platens are well known, none of them are associated with the continuous sheet feeding means and the single-piece sheet feeding means as in the present invention.

C. Problems to be Solved by the Invention Since the roller type platen feeds the printing paper along the curved path, it is easy to change the path. Therefore, it has been adopted for both continuous and single-sided printing devices. . However, when the single-sided sheet is a carbon copy type sheet consisting of a plurality of five sheets stacked, for example, the radii of each sheet differ from the center of the roller type platen, so that the lower sheet and the upper sheet are The feeding position of the upper and lower sheets gradually shifts, so the so-called single ring (S
There was a problem of causing "HINGLING" (Fig. 3).

On the other hand, if the flat paper platen is used to overlap the feeding path of the single-sided paper with the feeding path of the continuous paper, the feeding means (pin feed tractor) for the continuous paper becomes an obstacle when inserting the single-sided paper. There was a problem to say.

The pin feed tractor is a cause of obstruction of the insertion of the single-sided sheet due to the plurality of pins protruding on the continuous sheet feeding surface and the presence of the sheet pressing plate above the pins.

An object of the present invention is to solve the above two problems at the same time.

D. Means for Solving Problems (FIG. 1) The problem of shingling should be solved if the paper feeding path in the printing station comprising the printing head and the platen is made linear. Therefore, the platen adopts a flat plate type which gives a linear feeding path instead of the roller type which gives a curved feeding path. Another problem that arises from this, namely the obstruction of the insertion of the single-sided paper due to the overlapping of the feeding paths of the continuous paper and the single-sided paper, causes the end portion of the pin feed tractor at least near the platen to move the paper feeding path A. -A
The solution is to evacuate from Pin feed
The entire tractor may be retracted from the paper feed path.

E. Embodiments (FIGS. 1, 4, and 5) The printing apparatus shown in FIG. 1 has a print head 1, a flat platen platen 2 for providing an opposing flat surface to the print head, feed rollers 3, 4,
It includes a pin feed tractor 5 for feeding continuous forms.

The platen 2 may have any trapezoidal shape, a long quadrangle, a circular shape with a chord, or the like, as long as the platen-holding portion gives a linear path during printing. The rollers 3 and 4 sandwich and feed the sheet between the upper roller and the lower roller, respectively.
The roller 4 is for feeding the front end of the printing paper toward the platen 2, and it is also possible to adopt a configuration without this.

The pin feed tractor 5 has a series of pins 5a that engage with feed holes of continuous paper, a paper pressing plate 5b, and a hinge 5c that attaches the paper pressing plate to the main body of the pin feed tractor so as to be openable and closable. The tip end of the pin 5a and the paper pressing plate 5b project upward from the paper feeding radial surface AA. The series of pins 5a is driven by a gear 7, which gear 7 is driven by a motor 10 via a toothed belt 9
Is engaged with.

FIG. 4 is a side view of the continuous paper feeding state shown in the perspective view of FIG. The paper feed line of the pin feed tractor 5 connects the upper surface of the platen 2 and the sandwiching point of the feed roll 3 to linearly feed the continuous paper 6. Since the path of the continuous paper 6 shown in FIG. 4 is inclined by about 45 °, it is convenient for observing the printing state and inserting or removing the single-sided paper, but if necessary, it can be set in the range of 0 ° to 90 °. It may be selected at any angle.

Here, it is necessary to switch to single-sided paper. The continuous paper used up to now is Pin Feed Tractor 5
However, it is necessary to cut or reverse feed so that the remaining portion of the continuous paper does not protrude from the end of the pin feed tractor 5 near the platen (6a in FIG. 5).
reference). Then, when the lever 12 is rotated clockwise around the pivot 13 by the rear cam 11 (or any means such as an electromagnet) (FIG. 1), the end portion of the pin feed tractor 5 near the platen 2 is rotated. Is rolled around the shaft 14 in the clockwise direction and retracted below the sheet feeding surface AA.
At this time, the gear 7 is disengaged from the gear 8. Therefore, even if the remaining continuous paper on the pin feed tractor 5 is not removed, no trouble occurs. Single piece paper 15 is the fifth
Inserted from the upper right of the figure. At this time, the lower end 15a of the single piece paper 15 slides on the paper pressing plate 5b of the pin feed tractor 5 and the continuous paper 6 left on the paper pressing plate 5b to maintain a substantially linear feeding path. If you don't have continuous paper 6,
The lower end 15a of the single-piece sheet 15 slides on the sheet pressing plate 5b and the intermediate guide plate 16 to maintain a substantially linear feeding path. The single piece paper 15 may be inserted from the lower left to the upper right of the figure.

The operation when the continuous paper is used again will be described.
When the cam 12 rotates the lever 12 counterclockwise,
The pin feed tractor 5 returns to the paper feeding path again. At this time, the gear 7 engages with the gear 8 to complete the driving force transmission relationship with the pin 5a. At this time,
When the teeth of the gears 7 and 8 collide with each other and good meshing cannot be obtained, a control signal for rotating the motor 10 in the normal direction and the reverse direction is supplied for a short time so that the gear 8 is rotated clockwise and counterclockwise. It suffices to slightly vibrate in the direction.

F. The printing apparatus of the present invention, which can use both continuous paper and single-sided paper, does not have the roller type platen which gives the curved feeding path, and therefore does not cause the shingling phenomenon when the copy-type single-sided paper is used. Therefore, the problem of print misregistration can be solved. By retracting the pin feed tractor from the paper feed path, the problem of interference with single-sided paper is solved, and at the same time, the drive force transmission relationship to the pin is automatically cut off, eliminating the need to remove the remaining continuous paper from the pin feed tractor. did. For this reason, it is possible to save the labor of attaching and detaching the continuous paper to and from the pin feed tractor at the time of paper switching, so that the productivity of the printing work is increased.

[Brief description of drawings]

FIG. 1 is a perspective view showing the overall configuration of the present invention, FIG. 2 is a schematic view of a conventional technique, FIG. 3 is a view showing problems of a roller platen, and FIG. 4 is a schematic view of continuous paper feeding. FIG. 5 and FIG. 5 are schematic diagrams showing the positional relationship when a single piece of paper is inserted. 1 ... Print head, 2 ... Platen, 3, 4 ... Feed roll, 5 ... Pin feed tractor, 5a ... Pin,
5b ... Paper pressing plate, 5c ... Hinges, 6 ... Continuous paper,
7, 8 ... Gear, 9 ... Toothed belt, 10 ... Motor,
11 ... Cam, 12 ... Lever, 15 ... Single-sided paper, A
-A: Paper feeding surface.

Claims (3)

[Claims] 1. A print head, a platen arranged to face the print head, and a pin feed for feeding a continuous sheet having a feed hole at a side edge by engaging the feed hole.
A pin feed tractor and at least one set of feed rollers for receiving the paper fed from the pin feed tractor and feeding the paper in a linear path over the platen. The respective paper feed paths of the feed rollers are arranged so as to be on a straight line, and when feeding a single piece of paper having no feed hole, the end portion of the pin feed tractor at least close to the platen is fixed. A printing apparatus characterized in that the single-piece sheet is allowed to pass through the uppermost portion of the pin feed tractor by retracting from the sheet feeding path. 2. When the end of the pin feed tractor at least near the platen is retracted from the paper feed path, the feeding drive force to the pin feed tractor is adjusted so as not to feed continuous paper. The printer according to claim (1), characterized in that the supply is cut off. 3. The printing apparatus according to claim 1, wherein the platen has a flat plate facing the print head.