JP2000062281A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce sheet feed load while protecting a sheet detector against static electricity in a printer to be set with a roll sheet while throwing where sheet feed load is generally increased and a sheet detector is exposed and susceptible to electrostatic breakdown. SOLUTION: A leaf spring shock absorbing plate 11 is snap fitted to a sheet path and when a load is applied due to abrupt sheet feed, the shock absorbing plate 11 flexes in the direction of arrow B to absorb the load. Since the shock absorbing plate 11 covers a sheet detector 14, it serves as an arrester for preventing strong static electricity from dropping onto the sheet detector.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer for printing predetermined data on a roll-shaped recording paper or the like, and more particularly to a roll-throw-in type printer in which roll paper can be easily set. .

[0002]

2. Description of the Related Art Conventionally, various roll paper throw-in type printers have been proposed, as described in Japanese Patent Publication No. 8-505576, which allows easy roll paper setting. In this, when the lid is opened, the paper storage portion and the paper path are exposed, roll paper is thrown in, and paper can be set by closing the lid. These printers are easier to set the roll paper than the type in which the hollow shaft roll paper is axially supported, but there is also a problem that the paper feeding load becomes large. In order to reduce the load of the printer when feeding paper, various buffer mechanisms and paper tension mechanisms have been conventionally proposed. 62-1 Shokai
According to Japanese Patent Publication No. 79253, a cushioning member that bends the recording paper is provided between the storage unit for the recording paper and the paper feeding member, and when the recording paper is suddenly fed from the stopped state, the recording paper receives the recording paper. The cushioning member moves so as to elastically absorb the instantaneous tension.

[0003]

However, in the above-described conventional paper feed cushioning mechanism, the number of parts is large, the structure is complicated, and the cost disadvantage is brought about. Further, when a detector for detecting the presence or absence of recording paper is provided on the paper path, if the buffer mechanism of the related art is arranged, the paper path becomes long, which hinders downsizing of the printer. Further, in a printer in which the paper path is exposed, there is a problem that the paper detector is easily damaged.

Therefore, the present invention is intended to solve all of the above-mentioned problems of the prior art, and its purpose is to:
A throw-in type printer that can easily set roll paper,
It is an object of the present invention to provide a printer in which a paper feed load is reduced by a component added to a paper path, and at the same time, a paper feed buffer mechanism that also protects a paper detector is realized in a short paper path.

[0005]

In order to solve the above-mentioned problems, the invention according to claim 1 is such that a recording paper is rewound from the roll paper and a storage part for storing the roll paper. A printer having a paper feed unit for feeding the recording paper, a paper path for the recording paper from the accommodating unit to the paper feed unit, and a frame formed of a metal plate. A paper detector that detects the presence or absence of paper, and a displacement portion that displaces to bend the recording paper between the roll paper and the paper feeding portion and shorten the path length,
It is characterized in that it has a cushioning member formed of a conductive material and having a guiding portion arranged in the vicinity of the paper detector, and a grounding member electrically connecting the frame and the cushioning member.

In the above structure, the cushioning member made of a conductive material can displace and reduce the momentary load applied to the paper feeding portion when the paper is suddenly fed, and at the same time, recording is performed from this cushioning member. The static electricity of the paper can be released. The cushioning member is arranged in the vicinity of the paper detector so that even if a strong static electricity member approaches the paper detector, the static electricity will fall to the cushioning member before the static electricity falls to the paper detector. Act on.

According to a second aspect of the present invention, the cushioning member is formed of an elastic metal plate and is attached to a supporting member that is pressed against and supported by the earth member by utilizing the elasticity. It is characterized by being

In the above structure, the spring elasticity of the cushioning member itself is utilized, so that the cushioning member can be easily grounded by simply attaching the cushioning member.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of a printer according to the present invention will be described in detail below with reference to FIGS.

FIG. 1 is a sectional view of the printer of this embodiment, which can be roughly divided into a base portion 1 and a cover portion 2. A paper holder 10 for accommodating a recording paper P, a print mechanism portion such as a print head 8, and a cutter housing 9 are attached to a frame 13 of the base portion 1. The cover portion 2 is rotatably hinged to a fulcrum 3 located behind the recording paper storage portion of the base portion 1.

When setting the recording paper P, the operator first opens the cover portion 2. Then, the recording paper storage portion appears, the recording paper P is put into the recording paper storage portion, and the cover portion 2 is closed again. Then, the recording paper P is sandwiched in the paper path formed between the cover portion 2 and the base portion 1, and the recording paper P is held and set. FIG. 1 shows a state in which the cover portion 2 is in the closed position, and in this state, the printer can perform a printing operation and an automatic cutting operation.

The cover portion 2 has a cover frame 20 which is a pressed part of a sheet metal, a fixed blade 4 of an auto cutter, an outer cover 21, and a platen roller 22 for paper feeding attached to the cover portion 2. When the cover portion 2 is at the closed position. The recording paper P is sandwiched between the platen roller 22 and the print head 8, receives power from a motor (not shown), and when the platen roller 22 rotates, the recording paper P is fed by the frictional force.

The printed recording paper P is temporarily stopped, the movable blade 5 arranged in the cutter housing 9 receives the power of the drive mechanism, moves from the retracted position to cross the paper path, and crosses the fixed blade 4. . As a result, the recording paper P is cut, and after the recording paper P is cut, the movable blade 5 is returned to the retracted position again.
Auto cut operation ends.

Next, the paper holder 1 which is also a supporting member
The structure of 0 will be described with reference to FIG. The paper holder 10 is a resin molded product, and has a storage portion for the recording paper P and a paper path portion for guiding the recording paper P to the platen roller 22. A hook portion 101 is provided in the paper path portion of the paper holder 10, and the paper detector 14 is attached thereto by snap fitting. The paper detector 14 is a reflection type photo sensor. Further, a slit groove 102 is provided in the paper path portion of the paper holder 10, and the mounting portion 1 of the buffer plate 11 formed of a stainless leaf spring material is provided therein.
Attach 12 by snap fit. Then, the photo sensor of the paper detector 14 is surrounded by the dielectric portion 1 of the buffer plate 11.
It becomes the shape that 14 surrounds. The buffer plate 11 is provided with a detection hole 110 so as not to interfere with the optical axis of the photosensor.

Two screw holes 105 are provided on each of the left and right side surfaces of the paper holder 10, and a frame 13 which is a pressed part of a sheet metal is screwed to the left and right.

Next, FIG. 3 which is a detailed sectional view of the paper feeding portion.
The function of the buffer plate 11 will be described with reference to. The buffer plate 11 is inserted into the slit groove 102 of the paper holder 10, and the hook portion of the buffer plate 11 is hooked on the hooking portion 103 to prevent the buffer plate 11 from coming off. In addition, the end portion 1 of the buffer plate 11
Reference numeral 11 is a shape that is inserted into the hole 104 of the paper holder 10. As a result, the end portion 111 is not exposed,
The operator does not touch the end of the buffer plate 11 by mistake, and it is difficult to deform the buffer plate 11.

The recording paper P held by the platen roller 22 and the print head 8 is stopped by the platen roller 22.
Immediately with the rotation of, it is sent in the direction of arrow A. At this time, tension is applied to the recording paper P in the direction of arrow C due to the inertia of the roll paper received by the recording paper storage portion of the paper holder 10. Then, the displacement portion 1 of the buffer plate 11 having spring property
13 is somewhat bent in the direction of arrow B to relieve this tension.
As a result, the platen roller 22 is not instantaneously subjected to a large load, and the paper feed pitch is not disturbed.
When the paper is continuously fed at a constant speed and the roll portion of the recording paper P is smoothly rotating at a constant speed, since no acceleration is applied, only static load due to friction of the paper holder 10 is generated, and a large load is applied. Since there is no strain, the buffer plate 11 does not need to operate. When the predetermined paper feed is performed and the platen roller 22 stops, the buffer plate 11 returns to the original position.

Further, the metal member 12 for grounding is sandwiched by the frame 13 and fixed by screws like the paper holder 10. A part of the mounting portion 112 of the buffer plate 11 is in contact with the grounding metal member 12 by utilizing spring elasticity.
The metal plate 12 for grounding is electrically connected to the ground side of the power source for driving the printer through the frame 13. That is, the buffer plate 11 is snap-fitted to the paper holder 10
The structure is such that it can be grounded simply by inserting it into the mounting portion 112 of. As a result, the buffer plate 11 does not become a floating metal, and static electricity can be released.

Further, in this printer, the paper detector 14 is arranged inside the buffer plate 11, and by the buffer plate 11,
Since the recording paper P is always biased so as to be in close contact with the platen roller 22, the distance between the recording paper P and the paper detector 14 is stabilized at a fixed distance, and the detection accuracy can be improved. Further, when using a photosensor as in this example, a model having a wide detection range is expensive, but this example has an advantage that an inexpensive photosensor having a narrow detection range can be used.

FIG. 4 is a perspective view when the cover portion 2 of the printer is opened. A metal buffer plate 14 covers the photo sensor of the paper detector 14. In this open state, even if a strong static electricity member is brought close to the photo sensor, the static electricity does not fall to the buffer plate 14 and the photo sensor is not destroyed. That is, the buffer plate 14 also serves as a lightning rod. As described above, the electrostatic protection of the paper detector according to the present invention is a particularly effective technique for the printer having the structure in which the cover portion 2 is opened and the paper detector 14 is exposed.

[0021]

As described above, according to the present invention, the buffer member is made of a conductive material having a means for releasing the static electricity of the recording paper, and a part of the dielectric portion of the buffer member is located near the paper detector. Therefore, in the short paper path, it is possible to reduce the paper feed load, prevent unevenness of the paper feed pitch, and at the same time protect the paper detector from static electricity.

If the dielectric portion has a shape that covers the periphery of the detector, the effect of dielectric is further improved.

Further, according to the present invention, one component of the leaf spring component can provide two different effects of improving the paper feed and protecting the paper detector. Therefore, an inexpensive printer can be obtained without increasing the number of components. To be

Further, according to the present invention, the buffer plate can be easily attached and grounded by snap-fitting using elasticity, and a printer having easy assembling property can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a printer according to the present invention.

FIG. 2 is a perspective view showing a configuration of a paper holder of the printer.

FIG. 3 is a cross-sectional view of main parts of the printer.

FIG. 4 is a perspective view of the printer with the lid open.

[Explanation of symbols]

1 base 2 cover 3 fulcrum 11 buffer plate 12 Ground metal member 14 Paper detector 22 Platen roller P recording paper

Claims (2)

[Claims] 1. A container for accommodating roll paper in which recording paper is wound in a roll shape, a paper feed unit for conveying recording paper unwound from the roll paper, and from the container to the paper feed unit. A printer having a paper path for the recording paper and a frame formed of a metal plate, a paper detector for detecting the presence or absence of the recording paper on the paper path, the roll paper, and the paper feed unit. A buffer member formed of a conductive material, which includes a displacement portion that displaces the recording paper between and to bend so as to shorten the path length, and a guide portion that is arranged in the vicinity of the paper detector, A printer comprising: a ground member that electrically connects the frame and the buffer member. 2. The cushioning member is formed of a metal plate having elasticity and is attached to a support member that is pressed against and supported by the earth member by utilizing elasticity. The printer according to 1.