JPH018370Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a printing device for an impact printer in which when a striker of a printing head hits an ink-impregnated platen through a printing paper, ink from the platen adheres to the printing paper to perform printing.

In this type of printing device, the platen is made of a water-absorbing porous material, such as plastic or impregnable metal, impregnated with ink. In this case, it is advantageous to construct the platen by inserting the ink impregnating material into a rotary cylinder having a plurality of slits formed in the longitudinal direction of the circumferential surface so that the portion of the ink impregnating material facing the slits is used as an ink transfer surface. . In other words, by doing this, the impactor of the print head hits the ink transfer surface of the platen through the printing paper, and when the ink on that ink transfer surface is consumed, a new ink transfer surface is transferred to the print head by rotation operation. Since it is opposed to the striking element, it is possible to perform printing without shading, and the rotary cylinder coated with an ink-impregnating material can also suppress evaporation of ink. Conventionally, such a printing device is known from Japanese Patent Laid-Open No. 74892/1983.
However, if a structure is adopted in which the rotary shaft of the platen is simply supported in a bearing hole, there is a problem in that the platen generates considerable vibration, which adversely affects printing quality.
This vibration of the platen is caused by the existence of a small gap between the bearing hole and the rotating shaft and by the continuous impact of the striker on the platen.

The purpose of this invention is to eliminate such problems and provide a printing device that provides good print quality.

In other words, this invention consists of: (A) Inserting an ink impregnating material into a rotating cylinder with a plurality of slits formed in the longitudinal direction of the circumferential surface, and using the portion of the ink impregnating material facing the slits as an ink transfer surface, each ink in the rotating cylinder is A platen with a positioning portion provided on a surface perpendicular to the transfer surface is disposed facing the striker of the printing head, and (B) a positioning portion is fixed below the platen, and the positioning portion is attached to the positioning portion. This is a printing device for an impact printer in which the positioning part is removably connected, and (C) the bearings of the bearing members disposed on both sides of the platen are holes shaped to allow vertical movement of the platen rotating shaft.

With this idea, a positioning part is provided on a surface perpendicular to each ink transfer surface of the rotating cylinder, the positioning part is fixed below the platen, and the positioning part is removably connected to this positioning part. This is to prevent vibration of the platen and to ensure that the ink transfer surface to be switched accurately faces the striker of the print head. Furthermore, in this invention, the bearings of the bearing members disposed on both sides of the platen are made with holes shaped to allow vertical movement of the platen rotation axis, which allows the positioning part and the positioning part to be attached and detached, and the platen can be rotated. This is to make it happen.

Thus, with this invention, it is possible to obtain a printing device that eliminates the problem of platen vibration and provides good printing quality.

This invention will be explained below with reference to the drawings, and preferred embodiments of this invention will also be shown.

Figure 1 showing the printing device of an impact printer
FIG. 4 consists of a print head 1, a platen 2, a positioning section 3, and a bearing member 4. The print head 1 is movable back and forth, and ejects a print wire in accordance with a print command from a control circuit of the printer. The platen 2 is disposed facing the printing wire of the printing head 1 and is composed of a rotating shaft 5, a rotating cylinder 6, and an ink impregnating material 7. The rotating cylinder 6 has four slits 8 (two of which are shown in the figure) in the longitudinal direction of the circumferential surface, and the ink-impregnating material 7 is inserted into the slits 8 so as to face the slits 8. The four portions are the ink transfer surface 9. A positioned portion 10 is provided on a surface of the rotary cylinder 6 in a direction orthogonal to the four ink transfer surfaces 9. Positioning part 3
is fixed on a stand 11 placed below the platen 2, and the positioning portion 10 is fixed to the positioning portion 3.
are detachably connected. The bearing members 4 are arranged on both sides of the platen 2, and the bearings 12 are connected to the rotating shaft 5.
The hole is shaped to allow vertical movement. 13 is a knob, and 14 is a printing paper.

Next, the effect will be explained. When the platen 2 is raised along the bearing 12 by holding the knob 13,
The connection between the positioned part 10 and the positioning part 3 is released, and the platen 2 can be rotated. Next, the platen 2 is rotated by a predetermined angle (90 degrees in this example) and lowered, and the rotating cylinder 5 is oriented perpendicularly to the ink transfer surface 9 that is to be opposed to the printing wire of the printing head 1.
The positioned portion 10 provided on the surface is coupled to the positioning portion 3. In this way, the new ink transfer surface 9 can be accurately opposed to the printing wire of the printing head 1, and after the part to be positioned 10 and the positioning part 3 are connected, the platen 2 will not vibrate even if it is continuously struck by the printing wire. .

In the above description, the positioned portion 1 provided on a surface perpendicular to each ink transfer surface 9 of the rotating cylinder 6
Although the number of 0s is not particularly limited, two cases give preferable results. Further, the bearing member 4 may also serve as the stand 11.

According to a preferred embodiment of this invention, (1) The positioned portion 10 of the platen 2 is hole-shaped. The hole-shaped positioned portion 10 requires a smaller gap between the platen 2 and the print head 1 than in the case of a protrusion, which prevents the flight distance of the striker from becoming large and has a positive effect on the design of the print head. .

(2) The ink transfer surface 9 of the platen 2 is flat. The flat ink transfer surface 9 provides familiarity to the striker and improves printing quality. In this case, the cross-section of the platen 2 will be irregular, but if the bearing 12 is made sufficiently long in the vertical direction so that the platen 2 can be raised to a position beyond the print head 1, the platen 2 will be in a position relative to the print head during rotation.
Collision between platen 2 and print head 1 can be prevented.
There is no need to create a large gap between the two. Alternatively, a hook-shaped hole may be formed with the upper end of the hole bent toward the side opposite to the print head 1. Since the hook-shaped hole allows the platen 2 to be rotated by moving in the direction of arrow a in FIG. 2, the bearing member 4 can be kept low and is advantageous in downsizing the printing device.

(3) The rotating cylinder 6 is the ink transfer surface 9 of the ink impregnating material 7
It is to cover the other parts. In this way, ink evaporation can be further prevented. As shown in FIG. 5, such a platen 2 consists of a rotary cylinder 6 made up of a main body 15 and a cap 16. The main body 15 and the cap 16 are provided with an insertion hole 18 through which the rotary shaft 5 passes, and an ink-impregnated material is inserted into the platen 2. It can be made by embedding coupling tools 17 for coupling the rotating shaft 5 at both ends of the rotation shaft 7.

[Brief explanation of the drawing]

Fig. 1 is a plan view of the invented device, Fig. 2 is a side view of the device, Fig. 3 is a front view of the device, Fig. 4 is an enlarged cross-sectional view taken along line A-A in Fig. 3, and Fig. 5 is a side view of the device. FIG. 2 is an exploded perspective view of a platen used in this invention. DESCRIPTION OF SYMBOLS 1... Printing head, 2... Platen, 3... Positioning part, 4... Bearing member, 5... Rotating shaft, 6...
...Rotating tube, 7... Ink impregnating material, 8... Slit, 9... Ink transfer surface, 10... Positioned part, 12... Bearing, 15... Main body of rotating tube, 16
...Rotating cylinder cap.

Claims (1)

[Claims for Utility Model Registration] 1 (A) An ink-impregnating material 7 is inserted into a rotary cylinder 6 in which a plurality of slits 8 are formed in the longitudinal direction of the circumferential surface, and a portion of the ink-impregnating material 7 facing the slits 8 is transferred with ink. A positioning portion 10 is defined as a surface 9, and a positioned portion 10 is provided on a surface in a direction orthogonal to each ink transfer surface 9 of the rotary cylinder 6.
(B) A positioning part 3 is fixed below the platen 2, and the positioning part 1 is attached to the positioning part 3.
(C) Further, the bearings 12 of the bearing members 4 disposed on both sides of the platen 2 are formed into holes shaped to allow the vertical movement of the platen rotating shaft 5. 2. The device according to claim 1, in which the rotary cylinder 6 of the platen 2 comprises a main body 15 and a cap 16. 3. The device according to claim 1, wherein the positioning portion 10 of the platen 2 is hole-shaped. 4. The ink transfer surface 9 of the platen 2 is flat, and the bearing 12 of the bearing member 4 is a hook-shaped hole with the upper end of the hole bent toward the side opposite to the printing head 1. Apparatus described in section.