JPH0154199B2 - - Google Patents

Description

[Detailed Description of the Invention] [Summary] The bearing portion of the paper guide is held by the support shaft inserted into the first predetermined hole of both side frames, and the paper guide is inserted into the second predetermined hole of the left and right side frames to form the slit of the bush. By inserting the paper guide in accordance with the thickness of the paper guide, accuracy can be ensured without requiring gap adjustment between the platen and the paper guide, and the paper guide can be easily fixed without applying excessive force.

[Industrial application field]

The present invention relates to a paper guide mechanism for a serial printer, and more particularly to an improvement in a paper guide fixing mechanism.

In recent years, various printers have been developed and put into practical use for computer terminal devices, etc., but continuous paper with feed holes on both sides, such as continuous slips, is often used as the printing paper for these printers. The leading end of the stored continuous paper passes through a paper guide and is wrapped around a platen member, and then used by setting a feed hole in a sprocket of a media transport section.

The gap between the paper guide and the platen requires precision in order to ensure the accuracy of the line feed amount and prevent jams, and it takes a lot of man-hours to position the paper guide and adjust the gap when assembling it to the printer, so we developed a mechanism that can easily do this. is desired.

[Conventional technology]

The conventional method will be explained below using a wire dot printer as an example with reference to FIGS. 1 and 2.

FIG. 1 is a plan view showing the excitation of a wire dot printer to which the present invention is applied, and FIG. 2 is a side view showing the paper guide mechanism of FIG. 1.

In the figure, 1a is a paper guide, 2 is a screw hole, 9 is a side frame, 10 is a platen, 11
is printing paper, 12a, 12b are sprockets, 1
3 is a carrier, 15 is a guide shaft, 16 is a feed screw, 17 is a belt, 19 is a motor, 20 is an ink ribbon cassette, 20a is an ink ribbon, 2
1 indicates the print head.

As shown in FIG. 1, the wire dot printer has a side frame 9, and a platen 10 is rotatably supported on the left and right side frames 9.

A printing paper 11 is wound around the platen 10, and the printing paper 11 is sent in the direction of arrow A in the figure by sprockets 12a and 12b of the medium transport section 12. On the other hand, at the front of the platen 10, that is, at the bottom in the figure, a carrier 13 is slidably fitted into a guide shaft 15 provided parallel to the platen 10.
The carrier 13 is similarly screwed into a feed screw 16 provided parallel to the platen 19. Feed screw 1
6 is connected to a motor 19 via a belt 17 or the like, and therefore, the feed screw 16 can move the carrier 13 in the directions of arrows C and D in the figure by the forward and reverse rotation of the motor 19. An ink ribbon cassette 20 is mounted on the carrier 13, and an endless ink ribbon 20a is mounted on the ink ribbon cassette 20.
is built in with a part thereof exposed on the platen 10 side. Further, a print head 21 is installed in the carrier 13 surrounded by an ink ribbon cassette 20, and a plurality of print magnets having wires (not shown) are installed in the print head 21 to form prints using dots. It's coming.

Further, as shown in FIG. 2, the paper guide mechanism has a paper guide 1a whose tip end is located below the platen 10 with a predetermined gap G, is arranged to be inclined toward the rear of the platen 10, and has a bent portion. It is fixed to a side frame (not shown) through a screw hole 2 . The medium transfer section 12 is arranged above the paper guide 1a, and the shafts 22a, 22
It is supported by the side frame at b. The printing paper 11 is stored in a paper feed section (not shown), and its leading edge passes through the upper surface of the paper guide 1a, and is wound around the platen 10 while being guided by a gap G between the printing paper 11 and the platen 10.

With such a configuration, the printing head 21
When activated, the wire of the printing magnet collides with the printing paper 11 on the platen 10 shown in FIG. Printing is performed on the printing paper 11. When one line of printing is completed, the media transport unit 12 is driven to feed the printing paper 11 by a predetermined amount in order to feed a new line.
is transferred in the direction of arrow A.

[Problem to be solved by the invention]

As explained above, according to the conventional method, the paper guide 1a makes it easy to operate when winding the printing paper 11 around the platen 10, and also allows the printing paper 11 to be moved around the platen 10 during the printing operation of the printer.
In order to guide the platen 10 so as not to loosen or jam, it is necessary to adjust the gap G between the platen 10 and the platen 10 over the entire opposing surface at the time of assembly, and to manage the gap G with high accuracy. That is, if the gap G is too wide, the line feed amount will be disturbed due to the folds (perforations) of the printing paper 11, and if the gap G is too narrow, a jam will occur in the printing paper 11.

However, in order to ensure the accuracy of this gap G, the platen 10 and paper guide 1a must be
Insert a gap gauge between the tips of the side frame holes and the mounting screws. The problem is that not only is it difficult to achieve accuracy, but also the workability is extremely poor because tightening is done while adjusting the hole (or elongated hole).

SUMMARY OF THE INVENTION An object of the present invention is to provide a paper guide mechanism that is simple and easy to assemble without requiring gap adjustment between the paper guide and the platen.

[Means to solve the problem]

The present invention provides a paper guide mechanism that includes a platen member, a medium transfer section, a paper guide that guides a continuous medium transferred from a paper feed section to the platen member, and left and right side frames that support these. Bearings provided below both ends of the portion of the guide facing the platen member, support shafts that fit into the bearings through first predetermined holes provided in the left and right side frames, and the plate thickness of the paper guide. and a bush that rotatably fits into second predetermined holes provided in the left and right side frames, and the direction of the slit is in the direction of the end surface of the paper guide supported by the bearing part on the support shaft. This is a paper guide mechanism in which the bush is inserted into a second predetermined hole while aligning the two, and the paper guide is supported by a slit. Here, the first predetermined hole and the second predetermined hole
The predetermined holes are located at positions where the paper guide has a desired gap and inclination relative to the platen member.

[Effect]

When the bearing part of the paper guide is held by the support shaft inserted into the first predetermined hole of the left and right side frames, the fulcrum that determines the gap between the platen and the paper guide is supported. By aligning the center of the thickness of the paper guide with the center of the predetermined hole, and then inserting the bushing into the second predetermined hole with the slit of the bushing aligned in the direction of the paper guide, excessive force may not be applied to the paper guide. The gap between the paper guide platen member and the paper guide can be kept constant without requiring adjustment.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 3 and 4. The same reference numerals indicate the same objects throughout the figures. FIG. 3 is an exploded perspective view showing an embodiment of the present invention, and FIG. 4 is a side view of FIG. 3 after assembly.

In the figure, 1b is a paper guide, 3 is a bearing part, 4 is a support shaft, 5 is a bush, 5a is a slit, 10a is a platen shaft, 23 is a support shaft hole (first
(predetermined hole), 24 indicates a bushing press-fit hole (second predetermined hole).

As shown in FIG. 3, the paper guide 1b is provided with bearing portions 3 on both sides of the opposing portion while maintaining the gap G with the platen 10 by a method such as drawing with a press. .

The support shaft 4 has a support shaft hole 23 in the side frame (left and right side frames) 9 shown in FIG.
It is fitted through.

The bushing 5 has a slit 5a and a flange 5b having a width that fits the thickness of the paper guide 1b and passing through the center of the diameter. Hold 1b.

Further, as shown in FIG. 4, the side frame 9 is provided with a support shaft hole 23, a bushing press-fit hole 24, and a platen shaft hole 25, and the support shaft hole 23 is located at a distance c below the platen shaft hole 25. Moreover, the bushing press-fit hole 24 is provided at a position at a relative distance a, b from the platen shaft hole 25. The distance c is such that when the platen 10 is supported by the platen shaft hole 25 and the bearing portion 3 of the paper guide 1b is supported by the support shaft hole 23 by the support shaft 4, a gap G is ensured between the platen 10 and the paper guide 1b. The dimensions are set to Further, the distances a and b are set to dimensions that give a predetermined inclination to the paper guide 1b.

Since it has such a configuration, the order of assembling it from the disassembled state shown in FIG. 3 to the one shown in FIG. 2
A support shaft 4 is inserted into the paper guide 1b, and the support shaft 4 rotatably supports the bearing portion 3 of the paper guide 1b. At this time, a fulcrum is supported that determines the gap G between the platen 10 and the paper guide 1b by the distance c between the platen shaft hole 25 and the support hole 23.

Next, the paper guide 1b is rotated so that the center of the plate thickness passes through the center of the bushing press-fit hole 24.

Furthermore, press the tip of the bushing 5 into the bushing press-fit hole 24.
into the slit 5 by rotating the bush 5.
The inclination of the paper guide 1b is made to match the inclination of the paper guide 1b, and the bush 5 is press-fitted up to the flange 5b and fixed so that the paper guide 1b is inserted into the slit 5a. Therefore, the inclination of the paper guide 1b is determined by the relative distances a and b of the bushing press-fit hole 24 with respect to the platen shaft hole 25, and the paper guide 1b is fixed at a predetermined position. Accordingly, the gap G is secured.

In this way, by providing the bearing portion 3 on the lower side of the paper guide 1b facing the platen 10, the gap G can be maintained constant.
Furthermore, when the portion of the paper guide 1b facing the platen 10 is bent, the bearing portion 3 can be simultaneously punched and bent, ensuring machining accuracy and reducing costs. Also paper guide 1b
The support shaft 4 is inserted into the support shaft hole 23 of the side frame 9 without being screwed to the side frame 9, and the bush 5 is press-fitted into the bushing press-fit hole 24.
Since it is fixed to the side frame 9, it is easy to operate and the assembly work efficiency can be significantly improved.

Therefore, unlike the conventional method, when fixing the paper guide to the side frame, there is no need to insert a gap gauge between the platen and the paper guide to adjust the gap G. By accurately controlling the position of the platen shaft hole, the paper guide can be easily attached to the side frame while maintaining a desired gap with respect to the platen.

〔Effect of the invention〕

As explained above, according to the present invention, a bearing portion is provided on the lower side of the portion of the paper guide facing the platen member, a bush having a support shaft and a slit is provided, and the paper guide is inserted through the first predetermined hole of the side frame. Support the bearing part with the support shaft, align the paper guide with the center of the second predetermined hole of the side frame, fit the bush into the second predetermined hole so that the slit matches the paper guide, and insert the paper into the slit. By inserting and fixing the guide, it is possible to maintain a constant gap between the platen member and the paper guide without the need for adjustment.

The paper guide can be easily fixed to the side frame, reducing assembly man-hours.

No bending or screw processing is required to attach the paper guide to the side frame, reducing the number of processing steps.

It is possible to improve costs.

There is an effect.

[Brief explanation of drawings]

1 is a plan view illustrating a wire dot printer to which the present invention is applied; FIG. 2 is a side view illustrating the paper guide mechanism of FIG. 1; FIG. 3 is an exploded perspective view illustrating an embodiment of the present invention; FIG. 4 is a side view showing the embodiment. In the figure, 1a and 1b are paper guides, 3
is a bearing part, 4 is a support shaft, 5 is a bush, 5a is a slit, 9 is a side frame, 10 is a platen,
G indicates a gap.

Claims (1)

[Scope of Claims] 1. A paper guide mechanism comprising: a platen member, a medium transfer section, a paper guide that guides a continuous medium transferred from a paper feed section to the platen member, and left and right side frames that support these. Bearings provided below both ends of a portion of the paper guide facing the platen member; Supports that fit into the bearings through first predetermined holes provided in the left and right side frames. It consists of a shaft, and a bush which has a slit into which the thickness of the paper guide fits, and which rotatably fits into second predetermined holes provided in the left and right side frames, and is supported on the support shaft by the bearing portion. A paper guide mechanism characterized in that the bush is inserted into the second predetermined hole and the paper guide is supported by the slit while aligning the direction of the slit with the direction of the end surface of the paper guide.