JPS61146572A - Platen roller - Google Patents

Abstract

PURPOSE:To permit high-quality printing without color shift by providing a vertically movable clamper to hold cut papers set in a reciprocally movable manner on the periphery of the platen roller. CONSTITUTION:A cam shaft 15 is moved to the direction of X2, and clampers 6a and 6b are raised to the direction of Y1 by cams 16 and projected on the roller 1. When a cut paper 32 is sent onto the platen roller A by a paper supply mechanism, the cam shaft 15 is instantaneously moved to the direction of X1, the clampers 6a and 6b are lowered to the direction of Y2 in a sliding manner from the cam face, and the frontal end of the paper 32 is exactly held between elastic materials 10a and 10b below the clampers 6a and 6b and an elastic material 14 above a casing 12. Desired information can thus be orderly transferred on the cut paper 32 for every line, as in the case of printing on continuous paper.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a platen roller used in terminal printers such as thermal printers and inkjet printers.

(Prior art) Conventionally, as a terminal printer (hard copy device),
For example, thermal recording type printing in which a thermal head is applied to thermal paper to change the temperature of the paper, or thermal transfer printing in which a thermal head is applied to transfer paper coated with heat-melting ink and the dissolved ink is transferred to the recording paper. There is a device.

The printing mechanism of this type of thermal printer is such that thermal paper and recording paper are sandwiched between a group of thermal heads arranged in a row for one line and a platen roller. The roller is rotated by a small angle using a stepping motor or the like to print the next line.

The recording paper used in this type of printer is, for example, so-called cut paper cut in advance to a predetermined size such as A4 size, roll paper wound around a cylindrical shaft, or transparent paper at both ends for feeding. It is well known that two types of recording paper are commonly used: continuous paper, such as perforated and folded fanfold paper.

In the above printers, when using cut paper as recording paper, for example, as a means to prevent the paper from meandering, the cut paper sent from the paper feeder has both ends facing the platen roller. It is configured to be clamped by a clamp mechanism provided in the section and held on the platen roller.

In addition, when using the above continuous paper as recording paper,
It is impossible to print continuously on this paper with its leading edge clamped on the platen opening and wrapped around it in the same way as cut paper. For example, yellow (Y), magenta (M) and cyan (C) ) When attempting to transfer the three colors one after another, it is necessary to perform this by reciprocating the recording paper together with the platen roller.

(Problem to be Solved by the Invention) In this way, when trying to transfer the colors Y, M, and C sequentially onto the two types of recording paper using one platen row, in any case, the platen row The recording paper must be moved back and forth with the rollers.

For example, when printing using the above-mentioned cut paper, the above-mentioned conventional platen roller only clamps both sides of the leading edge of the paper using the clamp mechanism, so the reliability of the clamp is poor, and Y, M, C
In the process of sequentially transferring the three colors, the recording paper on the platen roller shifts slightly, which causes color misregistration (registration) and has the disadvantage that high-quality printing cannot be performed. .

(Means for solving the problems) The present invention has been made in view of the above-mentioned conventional drawbacks,
a cylindrical platen roller body that is rotatably supported by a machine body; a clamper that is movable up and down that clamps cut paper and that is arranged to move forward and backward on the outer peripheral surface of the platen roller body;
The clamper is composed of a first elevating means having a driving means for supporting the clamper and moving the clamper up and down, and a second elevating means for moving the first elevating means up and down, and the clamper feeds continuous paper. In this case, its upper surface is substantially flush with the outer circumferential surface of the platen roller main body, and when feeding the cut paper, the cut paper is held between its lower surface and the upper surface of the first lifting means. It is an object of the present invention to provide a platen roller characterized by having the following configuration.

(Embodiment) FIG. 1 is a longitudinal sectional side view showing a preferred embodiment of the platen roller according to the present invention, which is set in a state where continuous paper is used as recording paper. FIG. 2 is an external perspective view of the platen roller shown in FIG. 1.

The platen roller A is roughly composed of a platen roller main body 1, an elevating unit 7 (first elevating means), and a cam unit 8 (second elevating means).

A cylindrical platen roller body (hereinafter referred to as roller body) 1 having a rotating shaft 2 and supported by a machine body (not shown) has a plate-shaped elastic body made of elastic material such as rubber on its outer peripheral surface. 3 is uniformly fixed by baking or the like.

Reference numeral 4 denotes a plurality of pin-like protrusions arranged at predetermined intervals on both ends of the outer peripheral surface of the roller body 1, and the through holes of the fanfold paper are locked by the protrusions 4. As a result, the fanfold paper is fed in a predetermined direction together with the roller body 1.

In addition, the longitudinal direction (line direction) of the outer peripheral surface of the roller body 1
A pair of elongated holes 5a and 5b arranged on the same straight line are bored in the elongated holes 5a and 5b, and inside these elongated holes 5a and 5b, a pair of clampers 6a which can move forward and backward are arranged so as to close the elongated holes 5a and 5b. 6
b are provided respectively.

Reference numeral 7 denotes an elevating unit that controls the vertical movement of the clampers 6a and 6b, which is arranged near the inner circumferential surface of the roller body 1;
is a cam unit that operates the elevating unit 7, and the roller body 1 selectively moves continuous paper and cut paper by clamping, by selectively operating these elevating and lowering units 7 and cam unit 8. is possible.

The clampers 6a, 6b have plate-shaped elastic bodies 9a, 9b, 10a, 10b fixed to their upper and lower surfaces, respectively.
Shafts 11a and 11b hanging downward are supported by a casing 12 of the elevating unit 7 via a coil spring 13 so as to be vertically movable. Furthermore, when using continuous paper as shown in FIG. , its lower surface comes into contact with a plate-shaped elastic body 14 fixed to the upper part of the casing 12 to regulate its position when descending in the Y2 direction, and its upper surface is approximately flush with the outer circumferential surface of the roller body 1. It is one.

Note that 20 is a coil spring stretched between the housing 12 and the frame 1C installed in the roller body 1, and the housing 12 is constantly drawn toward the center of the roller body 1 by this coil spring 20. ing.

Further, H is a thermal head group in which thermal heads are arranged in a line, which are arranged at a predetermined interval in the line direction of the roller body 1, and this thermal head group H is transferred to the roller body through a transfer paper (not shown). The ink of the desired color of the transfer paper is transferred onto the recording paper by pressing the recording paper on the paper.

15 is the clamper 6a within the housing 12.

The cam shaft is equipped with a plurality of cams 16 that can come into contact with the shaft ends of the shafts 11a and 11b of 6b, and is slidably arranged in both the X+ and X2 directions. A spring 17 (suspended in tension) is fitted and inserted to apply a sliding force in the It is facing the arm 18a. Therefore, when the solenoid 18 operates and the arm 18a rotates counterclockwise about the shaft 19, the camshaft 15 moves in the X2 direction (to the right in the figure).
Each cam 16 is connected to the shaft 11a of the clamper 6a, 6b,
Since Ilb is pressed against the force of the coil springs 13, 13, the clampers 6a, 6b rise in the Y1 direction along the cam surface.

On the other hand, the cam unit 8 is arranged between the elevating unit 7 and the frame 1C, and is roughly composed of a cam shaft 21 and a pair of cams 22 and 23 fixed to the cam shaft 21. Become.

One end of the camshaft 21 is biased with sliding force in the X1 direction by a coil spring 24 stretched between it and the frame 1C, and the other end protruding from the roller body 1 is an operating arm 25a of a solenoid 25. Let's face it in a way that allows us to interact with it. Further, cams 22 and 23 on this camshaft 21 are connected to a pair of cam bins 12G and 1 which are suspended from the lower part of the housing 12 of the elevating unit 7.
2d. A heart-shaped guide groove 23a is formed in one of the cams 23 (on the right side in the figure), and this guide groove 23a is rotated by a leaf spring 28 on a support plate 27 fixed on the frame 1C. In cooperation with the biased rotating arm 29, a bushing lock/bushing off switch mechanism is constructed, for example, as shown in Japanese Utility Model Publication No. 16732/1983.

Therefore, at the same time as the solenoid 25 is operated, the operating arm 25a rotates clockwise about the shaft 26, and the camshaft 25a rotates clockwise about the shaft 26.
1 in the X2 direction, the cams 22 and 23 come into contact with the cam bins 12G and 12d of the housing 12, so the lifting unit 7 is moved by the arms 12a and 12b fitted into the roller bodies 1 1a and 1b. It ascends in the Y1 direction in a regulated state.

In addition, as the camshaft 21 moves in the X2 direction, the camshaft 21 is moved by the self-holding action of the push-lock/push-off switch mechanism, which is composed of another cam 23, the rotating arm 29, etc. Further movement of the elevating unit 7 is prevented while the elevating unit 7 is held raised at the top of the cams 22, 23.

Here, the specific operation of the platen roller A according to the present invention will be sequentially explained with reference to FIGS. 1 and 3.

(1) Continuous paper invoice 1! A (shown in FIG. 1) In this case, the pair of solenoids 18, 25 are inactive.

When the continuous paper is fed by the platen roller A, the cam unit 8 is not operated by the solenoid 25, and the pair of cams 22 and 23 on the cam shaft 21 are moved to the cam bins 12C and 12C of the housing 12 of the lifting unit 7, respectively. 12Ci, the lifting unit 7 is drawn toward the center of the roller body 1 by the elastic force of the coil spring 20 stretched thereon, and comes to rest at the lowest position of the grooves 1a and 1b. There is.

On the other hand, cams 16 and -1 of the camshaft 15 in the lifting unit 7
6 is also the shaft 11a of the clampers 6a, 6b.

This clamper 6a does not come into contact with the clamper 11b.
, 6b are connected to the housing 1 by the elastic force of the coil springs 13, 13.
The elastic bodies 10a, 10 on the lower surface of the
b are in contact with the elastic bodies 14 on the housing 12, respectively, to maintain the stationary position. Therefore, the pair of clampers 6a, 6b
As described above, the upper surface is flush with the upper surface of the elastic body 3 of the roller main body 1 without protruding therefrom.

Here, for example, when using continuous paper such as fanfold paper as the recording paper, the through holes are in the roll body 1.
The roller body 1 is engaged with the protrusion 4 of the roll body 1, and is driven to rotate in the same direction as the roll body 1 rotates without relative displacement.

Therefore, if the thermal head group H is pressed against the continuous paper side on the platen roller A through transfer paper (not shown), information for each line will be printed sequentially on the continuous paper as the platen roller A rotates minutely. be done.

In this way, for example, when the printing of the color Y is completed, the platen roller A is reversed to the initial printing position, and the next color M, etc., are sequentially overlapped correctly without shifting from the previous color, and the information is It becomes possible to transcribe.

■Feeding state of cut paper (shown in Figure 3) When holding cut paper on platen roller A and feeding it, in the state of Figure 1 (continuous paper feed form 1), solenoid 2
5, the operating arm 25a is activated by the coil spring 3.
At the same time, the cam shaft 21 of the cam unit 8 is moved in the x2 direction, so that the pair of cams 22 and 23 are rotated clockwise about the shaft 26 against a force of 0. 12c and 12d, and lift them in the Y1 direction along the cam surface. This camshaft 21 is ×
By moving in two directions, the other cam 23 and the rotating arm 29
The cams 22 and 23 on the axis of the lifting unit 7 are stopped at a predetermined position by the switch mechanism consisting of the
It maintains its resting position while the is raised.

When the elevating unit 7 rises, the elastic body 14 on the casing 12
The upper surface of the roller body 1 and the elastic body 3 on the roller body 1 are substantially flush with each other.

Here, when the other solenoid 18 is operated, its operating arm 19 resists the elastic force of the coil spring 31 and the other coil spring 17 tensioned by the camshaft 15, and moves from the position shown by the solid line to the two-dot chain line. Rotate counterclockwise to the position shown by and move the camshaft 15 in the x2 direction. This camshaft 15
Simultaneously with the movement of cam 16. ...16 is the clamper 6a,
The clamper 6a comes into contact with the shaft ends of the shafts 11a and 11b of the clamper 6b, and lifts it in the Y1 direction along the cam surface.
, 5b protrude above the roller body 1. This clamper 6
In the protruding state of a and 6b, when the cut paper 32 is fed onto the platen roller A from the paper supply machine tank of the device (not shown), the operation of the solenoid 18 is canceled by the control device (not shown) at the same timing, and the camshaft 15 is a coil spring 17
It moves instantly in the x1 direction due to the elastic return force of. Due to this movement of the camshaft 15, the cam 16 moves to the position shown by the two-dot chain line, so that the clampers 6a, 6b, which had been held in the raised position, are moved by the coil springs 13, which are stretched thereon. The cut paper 32 slides down from the cam surface in the <Y2 direction due to the elastic return force of the cut paper 32, and the front end of the cut paper 32 is attached to the elastic bodies 10a and 10 on the lower surface of the clampers 6a and 6b.
0b and the elastic body 14 on the housing 12.

Here, the thermal head group is pressed onto the cut paper 32 side on the platen roller 1 via the transfer paper, and as the platen roller A rotates by a minute angle, the desired printing is performed on the cut paper 32 in the same manner as in the case of the above-mentioned continuous paper. information is sequentially transferred line by line.

In this way, for example, when the printing of the color Y is completed, the platen roller A is reversed to the initial printing position, and the next color M and so on are sequentially printed correctly without shifting from the previous color. It becomes possible to record information on the cut paper 32.

As mentioned above, in the printing process for each color, the cut paper 3
2, the front end thereof is held uniformly on the roller body 1 by the clampers 6a and 6b, so that it does not shift from the roller body 1, and each color is accurately overlapped one after another to perform high-quality printing. becomes possible.

(Effects of the Invention) As described above, the platen roller of the present invention can not only print continuous paper, but also reliably and accurately hold cut paper on the platen roller using the same platen roller. , magenta, and cyan color transfer paper are sequentially overlapped and printed, the cut paper does not shift from the platen roller during the printing process, and high-quality printing can be performed.

[Brief explanation of drawings]

FIG. 1 shows a preferred embodiment of the platen roller according to the present invention, and is a longitudinal side view showing the platen roller set in a state where continuous paper is used as recording paper, and FIG. 2 shows the platen roller shown in FIG. 1. FIG. 3 is a vertical sectional side view showing the state in which cut sheets are set. 1...Platen roller body, 2...Rotating shaft, 3.9
a, 9b, 10a, 10b, 14... elastic body, 4.
...Protrusion, 6a, 6b... Clamper, 7... Lifting unit, 8... Cam unit, 12... Housing, 1
5.21...Camshaft, 16.22.23...Cam, 18.25...Solenoid. 72 Figure

Claims (1)

[Claims] a cylindrical platen roller body that is rotatably supported by a machine body; a clamper that is movable up and down that clamps cut paper and that is arranged to move forward and backward on the outer peripheral surface of the platen roller body;
The clamper is composed of a first elevating means having a driving means for supporting the clamper and moving the clamper up and down, and a second elevating means for moving the first elevating means up and down, and the clamper feeds continuous paper. In this case, its upper surface is substantially flush with the outer circumferential surface of the platen roller main body, and when feeding the cut paper, the cut paper is held between its lower surface and the upper surface of the first lifting means. A platen roller characterized by being configured as follows.