JPS6294368A - Printer - Google Patents

Abstract

PURPOSE:To enable the position of a support shaft to be easily adjusted, by fitting a cam member for position adjustment to a support shaft, and rotating the cam member to bring a reference part into contact with a cam surface. CONSTITUTION:An end part of a support shaft 6 is fitted into a window form cutout 9 which is provided in a frame 2 in a vertically elongate shape so that the support shaft 6 can be vertically moved. A cam member 8 is fitted to the end part of the support shaft 6, and the frame 2 is provided with a reference part consisting of a projection 10 brought into contact with a cam surface of the cam member 8. The projection 10 may be provided by partial punching of the frame itself, or may be constituted of a pin or the like fixed to the frame 2. To adjust the vertical position of the support shaft 6, the cam member 8 fitted over the shaft 6 is rotated so as to bring the projection 10 into contact with one of the recessed parts 12 of the cam member 8.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printer equipped with a support shaft that guides a carriage carrying a print head substantially parallel to a platen.

In the above-mentioned printers configured as daisy printers, wire dot printers, etc., the relative position, especially the height position, of the print head and platen must be set correctly to prevent characters printed on the paper from becoming partially faded. It is necessary to prevent the inconvenience of deterioration of print quality. For this reason, conventionally, when manufacturing a printer or during maintenance and inspection, etc., a spacer is inserted between the support shaft and a notch in the frame that supports the support shaft, and by selecting the thickness or number of spacers, the support shaft relative to the platen is is adjusting the position. However, according to this method, it is necessary to remove the support shaft when sandwiching the spacer, and the work of sandwiching the spacer itself is complicated, resulting in extremely poor workability.

An object of the present invention is to provide a printer that eliminates the above-mentioned drawbacks of the conventional printer and allows easy adjustment of the position of the support shaft.

In order to achieve the above object, the present invention has a configuration in which a cam member for position adjustment is attached to a support shaft, and the cam member is rotated to bring a reference portion into contact with the cam surface to adjust the position of the support shaft. propose.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic perspective view of the inside of the printer, and shows the platen 1.
is rotatably supported by frames 2 and 3 as shown in FIG. A support shaft 6 for guiding a carriage 5 carrying a print head 4 and another shaft 7 are also supported by the frames 2 and 3. The height position of the support shaft 6 is adjusted by a cam member 8, which will be described later.

During a printing operation, a printing member of the print head 4, such as a daisy wheel, is struck by a hammer or a wire is driven, whereby predetermined characters are printed on a sheet of paper (not shown) hung on the platen 1, and the print head A carriage 5 carrying a paper 4 is guided by a support shaft 6 and moves parallel to the platen 1, and characters are successively printed on the paper.

When the above-described printing operation is performed, print quality will deteriorate if the positional relationship between the platen 1 and the print head 4 facing it, especially in the example shown in the figure, the positional relationship in the height direction is not maintained correctly. Therefore, when manufacturing or maintaining the printer, it is possible to adjust the distance H in the height direction between the support shaft 6 and the platen 1 (Fig. 2), and set the height position of the print head 4 with respect to the platen 1 correctly. The details are explained below.

The end of the support shaft 6 fits into a window-shaped notch 9 formed in the frame 2, as shown in FIG. long formed.

Further, the aforementioned cam member 8 is attached to the end of the support shaft 6, and the frame 2 is provided with a reference portion consisting of a protrusion 1o that abuts the cam surface of the cam member 8. The protrusion 1o may be formed by half punching the frame itself, or may be formed by a pin or the like fixed to the frame 2.

As clearly shown in FIG. 3, a hole 11 through which the support shaft 6 passes is formed in the cam member 8, and a plurality of recesses 12 are formed in the cam surface. In this case, the distance rl*r2tr3...
are different from each other, and for a reference radius r consisting of, for example, r1=r-0,1+nm, r2=r-0,0
5mm, r 3=r, r4=r+0.05+nm, r
5=r+0.1on. The cam member 8 is normally fixedly connected integrally with the support shaft 6, but the cam member 8 is arranged so that they can rotate relative to each other.
can also be fitted onto the shaft 6.

In order to adjust the height position of the support shaft 6, it is only necessary to rotate the cam member 8 passed through the shaft 6 and to abut the protrusion 10 into one of the recesses 12. In other words, if the height distance from the protrusion 1o to the center of the platen 1 is H8, the distance H between the platen 1 and the support shaft 6 is:
H= H□ −r.

(i=1.2.3...), and the distance H is adjusted in stages according to the size of the radius r of the recessed part with which the protrusion 1o comes into contact. When the cam member 8 rotates, the support shaft 6
can move up and down without any trouble while being guided by the notch 9. A similar cam member is attached to the other end of the support shaft 6, and the support shaft 6 is kept parallel to the platen 1 by bringing a not-shown protrusion provided on the frame 3 into contact with the recess of the cam member. At the same time, the height position of the shaft 6 relative to the platen 1 can be adjusted.

The cam member 8 has - arcuate long hole 13
is formed, and a screw hole 14 is bored in the frame portion corresponding to this elongated hole 13.

After adjusting the position of the support shaft 6, a screw 15 is screwed into the screw hole 14 as shown by the chain line in FIG. 2, and the cam member 8 is fixed to the frame 2 by tightening the screw 15.

The same applies to the cam member on the other side (not shown).

As a result, the support shaft 6 is supported by the frames 2 and 3 while being reliably positioned relative to the platen l. Further, by loosening the screw 15, the distance H can be set to a target value by rotating the cam member 8 at any time and changing the recess 12 that abuts the protrusion 10, and by tightening the screw 15 again, the cam member 8 can be rotated, and therefore the support shaft 6 can be held immovably in the frames 2 and 3. In this way, the position of the support shaft can be adjusted without removing it from the frame, and the workability can be improved.

Conventionally, it was necessary to insert a spacer between the bottom 9a of the notch 9 in the frame and the shaft 6, so it was necessary to remove the shaft 6 from the frame and insert the spacer, which caused poor work efficiency. As shown earlier.

It is advantageous to fix the knob 20 to the cam member 8 and to rotate the cam member 8 by grasping the knob 20 and moving it in the direction of arrow A during the adjustment operation, since operability can be further improved.

The case where the vertical position of the support shaft 6 is adjusted has been described above, but it goes without saying that the present invention can also be applied to cases where the adjustment 8...cam member 12...concave shape is adjusted in other directions. It is also possible to configure the other support shafts 7 to have their positions adjusted according to the present invention, if necessary. It is clear that the position of the support shaft can be adjusted even if the cam surface of the cam member is formed into a simple arcuate curve, for example, without providing a recess. Further, it is also possible to configure the reference portion other than the protrusion to come into contact with the cam surface of the cam member.

According to the present invention, there is no need to remove the support shaft when adjusting the position of the support shaft with respect to the platen.
Predetermined adjustment work can be easily performed.

[Brief explanation of drawings]

FIG. 1 is a perspective view schematically showing the inside of a printer according to the present invention, FIG. 2 is a partially sectional side view of FIG. 1, and FIG. 3 is an enlarged view of a cam member.

Claims (2)

[Claims] (1) A cam member for position adjustment is attached to the support shaft that guides the carriage carrying the print head almost parallel to the platen, and the cam member is rotated to bring the reference part into contact with the cam surface to position the support shaft. A printer characterized by adjusting. (2) The printer according to claim 1, wherein a plurality of recesses are formed on the cam surface of the cam member, the distances from the center of the support shaft being different from each other.