JPH068061B2 - Printer recording medium ejection mechanism - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium ejecting mechanism used when ejecting a recording medium from a printer in a printer, and more particularly to a multi-mechanism using a thermal head and a platen drum. The present invention relates to such a discharging mechanism suitable for a color printer.

[Background of the Invention]

In a conventional printer, as described in Japanese Patent Publication No. 56-52756, recording paper is chucked on a platen drum for recording. Therefore, when the recording paper is conveyed, the recording paper is positively wound around the drum. The guide of the recording paper is relatively easy because there is no need to guide the recording paper positively or to remove the recording paper from the drum positively when discharging the recording paper. Therefore, in the checkless type printer as in the present invention, there is no effective method for reliably conveying and discharging the recording paper.

Under such conventional technical circumstances, an example of a conventionally proposed recording sheet discharging mechanism will be described with reference to FIG.

FIG. 3 is a perspective view showing a main part of a conventional example of a recording medium ejection mechanism. In the figure, 1a is a platen drum, 2a is a thermal head, 3a is recording paper, and 4a is a discharge member.

In FIG. 3, the recording paper 3a wound around the platen drum 1a is printed by using the thermal head 2a while rotating the drum 1a in the direction A, and then the outer edge of the drum 1a is knife-edge-shaped. The discharge member 4a is strongly pressed, and the knife edge portion is used to separate and discharge the recording paper 3a from the state in which the recording paper 3a is wound around the drum 1a.

Therefore, in such a conventional discharging mechanism, the knife-edge-shaped discharging member 4a is provided on the outer periphery of the platen drum 1a.
The platen drum 1a is often scratched in order to apply a strong force, and if there is a gap between the discharge member 4a and the outer periphery of the platen drum 1a, the recording paper 3a to be discharged passes through the gap. Therefore, there is a case in which the recording paper is not ejected and the entire mechanism has to be stopped by winding the recording paper in a gap.

As described above, a reliable and effective means for ejecting the recording medium in the printer has never been proposed.

[Object of the Invention]

It is an object of the present invention to record a recording medium wound around a platen drum and having a curl, without peeling the drum and without fail, regardless of the thickness and rigidity of the recording medium. It is to provide a medium ejection mechanism.

[Outline of Invention]

As a method of peeling and discharging the recording paper wound around the platen drum from the drum, there is a method of peeling the recording paper by applying a knife edge discharge member to the platen drum in the front of the recording paper in the conveying direction. As described above with reference to FIG. 3, in this method, the platen drum may be damaged as described above, and the shape accuracy of the discharge member and its support accuracy must be strictly controlled.

Therefore, in the present invention, the width of the recording paper is made larger than the width of the platen drum, and the portion of the recording paper protruding from the platen drum is raised by the first discharging member without bringing the member into contact with the platen drum. A second discharging member for separating the drum from the drum and further for receiving the central portion of the width of the paper and guiding it to the discharging is provided on the downstream side. In this way, the discharging member has a two-stage structure, such as bending of the recording paper. Even if there is, it is possible to surely discharge.

Example of Invention

 Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing an embodiment of the present invention, and FIG. 2 is a side view of the same. However, in FIG. 1, the first discharging member 4a and the second discharging member 4b are in the first position (discharging position), and in FIG. 2, these discharging members are in the first position. Are shown in a different second position (non-eject position).

In FIGS. 1 and 2, 1 is a platen drum, 2 is a thermal head, 2a is a resistor, 3 is recording paper, 3a is a print recording screen (print screen), 4a is a first discharging member, and 4b is a first discharge member. 2 discharge member, 4c support shaft, 5 guide block, 6 transport block, 7 paper guide wall, 7a insertion slot, 8 roller, 9 ink film, 10 delivery reel, 11
Is a take-up reel, 13 is an arm, and 13a is a support shaft.

First, the structure of a thermal transfer printer will be described with reference to FIG.

In FIG. 2, printing is performed by the thermal head 2, the ink film 9, the recording paper 3, and the platen drum 1.
That is, the ink application surface of the ink film 9 and the recording surface of the recording paper 3 are inserted face-to-face between the platen drum 1 and the resistor 2a of the thermal head 2, and a recording signal input to the thermal head 2 is recorded. Therefore, the resistor 2a generates heat, and the ink of the ink film 9 is transferred to the recording paper 3 to obtain a predetermined image.

The recording paper 3 is inserted from the insertion port 7a and is conveyed to the position of the heat generating resistor 2a of the thermal head 2 by the action of the platen drum 1 rotating in the A direction, the paper guide wall 7 and the pressure roller 12. An ink film 9 is held between the thermal head 2 and the platen drum 1 by a delivery reel 10 and a take-up reel 11 as shown in the figure, and the ink film 9 is also delivered according to the rotation of the platen drum 1. The reel 10 is taken up by the take-up reel 11 via the roller 8.

The recording paper 3 conveyed to the heating resistor 2a is pressed against the platen drum 1 and the thermal head 2 together with the ink film 9 and is transferred as described above while continuing the conveyance.

Since this printer performs multicolor printing,
The recording paper once transferred is then transferred together with the ink films of different colors between the heating resistor 2a and the platen drum 1 to transfer the recording paper 3 times in total (in the case of three-color printing). After being transferred between the heating resistor 2a and the platen drum 1 to be superposed on each other, the recording paper is ejected to the outside of the printer by a recording paper ejecting mechanism described later.

As described above, since the leading edge of the recording paper is conveyed without passing through the platen drum 1 through the guides such as the guide wall 7, the pressure contact roller 12, the ink film 9 and the thermal head 2, the recording paper is not ejected except when discharging the recording paper. , The recording paper 3 is actively guided so as to be wound around the platen drum 1, and
At the time of discharging the recording paper, a mechanism capable of surely peeling and discharging the recording paper 3 wound around the platen drum 1 is required.

Hereinafter, the operation of this embodiment will be described in detail with reference to FIGS. 1, 4, and 5.

However, FIG. 4 is a side view of the embodiment of the present invention when the first discharging member 4a and the second discharging member 4b are in the second position (non-discharging position), and FIG. 5 is the discharging member. It is the same side view when 4a and 4b are in a 1st position (discharging position).

The first discharging member 4a and the second discharging member 4b are integrated with each other, and at the time of discharging the recording paper shown in FIG. 5 and during the conveyance of the recording paper shown in FIG. 4 (in the case of multicolor printing, , The discharge members 4a and 4b are movable so that they can take different positions when they are conveyed multiple times without being discharged. However, when multicolor printing is not performed, the recording of FIG. 5 is performed. The discharging members 4a and 4b may be fixed at the position for discharging the paper,
It goes without saying that it is possible to configure the first discharging member 4a and the second discharging member 4b by separate parts to perform the same operation.

Returning to FIG. 1, the relationship between dimensions and engagement of each component in the direction perpendicular to the recording paper conveyance direction will be described.

Width W _a of the recording sheet 3, the width _b of the platen drum 1, and the width of the printing screen 3a and W _c, the relation of W _a> W _b> W _c a (Fig. 1 shaded portion 3a printing surface shown.) the first ejection member 4a is also located with between-out slight gap on both sides of the drum width W _b, at the intersection from the platen drum 1 of the recording sheet 3 and a portion which protrudes on both sides is there.

Since printing is recorded by pressure bonding between the platen drum 1 and the thermal head 2, the print screen width W _c needs to be smaller than the platen drum width W _b .

As described above, FIGS. 4 and 5 show the vicinity of the discharge mechanism during the recording paper conveyance and the recording paper discharge, respectively, and the discharge member 4b and the guide block 5 are indicated by B in FIG. The cross section seen from the -B direction is shown.

When the recording paper is conveyed, the discharge members 4a and 4b are in the positions shown in FIG. 4, and the recording paper 3 is guided between the thermal head 2 and the platen drum 1 and then guided by the ink film 9 to the roller 8. The recording paper 3 is guided and further passes through the transport block 6 to reach the discharge member 4a located at the transport position, but the portion of the recording paper 3 protruding to both sides of the platen drum 1 is guided by the first discharge member 4a in the platen drum winding direction. When further advanced, the central portion of the recording paper is also guided in the winding direction by the second discharge member 4b and the guide block 5 and advances to the guide wall 7.

In this way, when the discharge members 4a and 4b are in the transport position,
The leading edge of the recording paper is always guided in the winding direction of the platen drum. In this state, after the recording paper 3 has been transferred three times,
The discharge members 4a and 4b take the discharge position shown in FIG. After the leading edge of the recording paper passes through the thermal head 2, the roller 8 and the transport block 6, the portion protruding from both sides of the platen drum is peeled off from the outer peripheral surface of the platen drum by the first discharging member 4a as shown in FIG. However, at this time, due to the rigidity of the recording paper, the discharge direction, etc., the central portion of the recording paper may bend in the winding direction of the platen drum compared to both sides.

When the recording paper is further fed, the central portion of the recording paper reaches the second discharging member 4b located downstream thereof, and the first discharging member 4a.
The recording paper 3 is completely peeled off from the drum 1 by the interaction between the second discharge member 4b and the second discharge member 4b and discharged.

At this time, the second discharging member 4b does not need to have its edge portion strongly contacted with the outer periphery of the platen drum as seen in the conventional example shown in FIG. Just enough.

As described above, according to the present invention, since the recording paper discharge member can be arranged apart from the platen drum, the recording paper can be reliably conveyed and discharged without damaging the platen drum.

Further, although the thermal transfer type color printer has been described in the embodiment, the present invention can be applied to a printer or the like using a thermal paper having a similar recording paper conveyance path, and its application range is wide.

Further, the first discharging member 4a is not always required on both sides of the recording paper, and if it is on the upstream side of the second discharging member, it can be operated only by disposing on either one side.

〔The invention's effect〕

According to the present invention, without damaging the platen drum,
Further, the ejecting operation from the printer can be surely performed regardless of the thickness of the recording medium and the rigidity thereof, which is very effective in terms of reliability and life. Furthermore, by using this discharging mechanism, it is possible to convey the recording medium without a check, which is very effective in simplifying the mechanism and reducing the cost.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention, FIG. 2 is a side view of the same, FIG. 3 is a perspective view showing a main part of a conventional example of a recording medium ejection mechanism, and FIG. FIG. 5 is a cross-sectional view of the main part of the embodiment during transport, and FIG. 5 is a cross-sectional view of the main part during discharge. DESCRIPTION OF SYMBOLS 1 ... Platen drum, 2 ... Thermal head, 2a ... Resistor, 3 ... Recording paper, 4a ... First ejection member, 4b ... Second ejection member, 5 ... Guide block, 6 ... Conveying block, 7 ...
Guide wall, 8 ... Roller, 9 ... Ink film, 10 ... Delivery reel, 11 ... Take-up reel, 12 ... Pressing roller, 1
3 ... arm

Claims (2)

[Claims] 1. A recording medium discharge mechanism of a printer, wherein a recording medium is wound around a platen drum, and the recording medium conveyed as the platen drum rotates is separated from the platen drum and discharged. As a dimension in the width direction perpendicular to the, the size relation of dimensions is defined in the order of print recording width <platen drum width <width of recording medium, and on the downstream side of the leading end of the recording medium conveyed, from the outer periphery of the platen drum. A first position that engages with the leading edge of the recording medium protruding in the width direction and separates the recording medium from the outer peripheral surface of the platen drum, and a recording medium protruding in the width direction from the outer periphery of the platen drum. A first ejecting member that can be selectively arranged at a second position that engages with the leading edge of the recording medium and guides the recording medium in the winding direction of the platen drum; On the downstream side of the first discharge member, substantially parallel to the width direction of the platen drum,
A second discharging member arranged at a predetermined distance from the outer periphery of the platen drum, and by arranging the first discharging member at a first position, the first discharging member and the second discharging member are disposed. The recording medium ejecting mechanism of a printer, wherein the ejected recording member ejects the conveyed recording medium from the outer periphery of the platen drum. 2. A recording medium ejecting mechanism for a printer according to claim 1, wherein the first ejecting member and the second ejecting member are integrally formed, and the second ejecting member is also movable. A recording medium ejecting mechanism for a printer characterized by the above.