JPS6296256A - Paper presence detector for printer - Google Patents

Abstract

PURPOSE:To simplify a structure in making screwing work unnecessary as well as to improve the extent of assembling operation efficiency, by installing a lever body energizing plate spring solidly in a keeping member holding a lever body to a paper guide, and making it fitable and vice versa in the paper guide. CONSTITUTION:A plate spring 154, energizing a lever body 13 in one direction is solidly installed in a keep plate 15 holding a lever body 13 to a paper guide 1, and this keep plate 15 is made fitable and vice versa in the paper guide 11. And, making the paper guide 11 support the lever body 13, the keep plate 15 is fitted in the paper guide 11. If so, the lever body 13 is energized in one direction adjoining a paper feeding route by dint of the plate spring 154, whereby it is held by the paper guide 11, and a spring action is given simultaneously with the setting operation of the lever body 13. Therefore, screwing operation for setting the keep plate 15 to the paper guide 11 becomes unnecessary, so that a setting structure of the lever body 13 is simplified, thus assembling operation efficiency is improvable.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a device for detecting whether or not paper is loaded in a printer used for a personal computer, etc.
Especially regarding its assembly structure.

2. Description of the Related Art This type of printer is generally provided with a device for detecting whether or not paper is loaded in the printer so that a printing operation is not performed when paper is not loaded in the printer. This prevents ink stains on the platen due to printing operations when no paper is loaded on the printer's platen, and prevents stains on the paper due to platen stains.
Alternatively, it is intended to prevent accidents such as damage to the print head.

This device for detecting the presence or absence of paper loading includes a lever body commonly called a paper empty lever that is biased in one direction in contact with the paper and installed on the paper guide, and this lever body is rotated in the other direction by the operation of loading paper into the printer. There is a method in which the presence or absence of paper is detected by turning the photoelectric sensor on and off by rotating the lever body.

Conventionally, the structure of attaching the lever body to the paper guide in this detection method was to rotatably support the lever body on the paper guide, and to hook and pass a coil spring between one end of the lever body and the guide, thereby attaching the lever body to the paper guide. Force in one direction of contact. The lever body has one end connected to the paper feeding path with its rotation axis as a fulcrum, and is rotated in the other direction during the paper loading operation, and when all the paper has passed and is gone, it is returned to the original one direction by the biasing force of the coil spring. It is returned to the locked position where it is biased. By the rotation of this lever body, a photoelectric sensor consisting of a photodiode and a photosensor provided between the other end of the lever body is turned off, thereby detecting whether or not paper is loaded into the printer. .

Problems to be Solved by the Invention However, the conventional lever body installation has problems with the structure.
In addition to the presser member that holds the lever body to the paper guide,
A spring is required to bias the lever body in one direction, which not only increases the number of parts but also makes installation difficult.

Moreover, since the presser member is attached to the paper guide by screwing, a laborious screwing operation must be performed. As a result, the conventional structure has had the problem of poor assembly efficiency.

The present invention has been made in view of the above points, and an object of the present invention is to simplify the mounting structure of a lever body for detecting the presence or absence of paper, and to simplify the mounting work.

Means for Solving the Problems In order to achieve the above object, the present invention employs the following configuration.

The present invention biases one end of a lever body provided on a paper guide in one direction facing the paper feeding path, rotates this lever body in the other direction with the paper loading operation, and activates the photoelectric sensor by the rotational movement of It is applied to a device that detects whether or not paper is loaded by turning it on and off, and the structure is particularly unique in how the lever body is attached to the paper guide.

That is, the present invention is characterized in that a plate spring that biases the lever body in one direction is integrally provided with a presser member that holds the lever body on the paper guide, and the presser member can be fitted and removed from the paper guide. This aims to achieve the above objectives.

Is there a lever body in the paper guide in a configuration that exceeds the function? After being supported, when the presser member is attached to the paper guide, the lever body is urged by the leaf spring in one direction facing the paper feed path and is held by the paper guide. therefore,
At the same time as the lever body is installed, a spring action is applied to the lever body.

Further, the holding member can be attached by simply fitting the paper guide into position, and no screwing work is required.

Embodiments Below, embodiments of the present invention will be described with reference to the drawings.

1, 2, and 3 show a paper presence/absence detection device for a printer according to the present invention, in which 10 is a platen, 11 and 12 paper guides, 13 lever bodies, and 14 photoelectric Sensor A indicates paper.

The paper A is loaded into the printer by a paper guide 11 provided in a curved shape along the circumferential direction of the platen 10 and an upper paper guide 12 provided opposite to one end of the paper guide 11. Gap 10 formed
This is done by inserting the paper through 0 and wrapping it around the circumferential surface of the platen 10. A paper presence/absence detecting device is provided near the paper insertion opening 100 consisting of the paper guide 11 and the upper paper guide 12.

A notch 111 is formed in the upper part of the paper guide 11 to which the lever body [3] is attached. Bearing grooves 112, 112 for receiving support shafts 131, 131 of the lever body 13 are formed on both side edges of the notch 111 in a direction perpendicular to the feeding direction of the paper A. Bearing groove 112
, 112 , holes 113 , 113 are formed for attaching the presser plate closer to the paper insertion opening 100 .

Lever body 13 attached to bearing groove 1.12, 112
is formed into a substantially inverted shape, and support shafts 131, 131 are formed protruding from both sides of the bent portion 130. The lever body 13 has the other end 133 connected to the notch 11
1, and insert the support shaft 131.131 into the bearing groove 112,
112 so that one end 132 thereof is connected to the path of paper A. One end portion 132 of the lever body 13 is provided so as to be inclined in the insertion direction of the paper A, and the end portion is rotatably locked to the edge portion of the upper paper guide 12 . Then, the other end 1 of the lever body 13
33 extends downward. Other end 1 of lever body 13
33 is located between the photodiode 141 and the photosensor 142 of the photoelectric sensor]4 provided below.

When the lever body 13 is installed as described above, the presser plate 15 is attached.
is held by. The press plate 15 is made of a material having spring properties. The holding plate 15 has a substantially E-shape cut out in parallel from all sides, and has side pieces 1.51 and 15.
1 is bent into a substantially crank shape to form a bent portion 152, 1.
52 is formed. An intermediate piece 153 located between the opposite side pieces 151, 151 is largely bent at an angle near the end of the notch in the same direction as the bent portion 152, thereby forming a leaf spring portion 154. The other end of the holding plate 15 is bent at right angles in the same direction as the bent portion 152, and its tip is further bent inward into a substantially P-shape, where the locking claw portion 15 is bent.
5 is formed.

The presser plate 15 formed as described above has a bent portion 152.1.
52 formed on the upper part of the paper guide 11 is inserted into the holes 113, 113, the leaf spring part 154 presses the back of the other end 133 of the lever body 13, and the locking claw part 155 is attached to the paper guide 11. It is attached to the paper guide by locking it to the edge of the upper extension of the paper guide.

In this way, the presser plate 15 is attached to the paper guide 11 by fitting. Then, both sides 15 of the presser plate 15
1,151, the support shaft 131,1 of the lever body 13
31 is held in the bearing grooves 112, 112 to prevent removal. One end 132 of the lever body 13 is locked to the edge of the upper paper guide 12 by the leaf spring 154, and the other end 133 is biased and held in a state related to the photoelectric sensor 14.

In the above configuration, when paper A is loaded into the printer through the insertion slot 100 as shown in FIG. Do not press down in the other direction, lever body 13
rotates in the other direction around the shaft 131. Then, the other end 133 of the lever body 13 comes off the W: electric sensor 14, and the light on the emitting side is detected on the light receiving side. This will detect that paper is present. When all the sheets of paper A have been fed and are removed from one end of the lever body 13, the lever body 13 is returned to the original state shown in FIGS. 1 and 3 by the biasing force of the leaf spring portion 154.

Then, the other end 133 of the lever body 13 engages the photoelectric sensor 14, and the light from the light emitting side is cut off, turning off the photoelectric sensor. Now, it is detected that there is no paper. In the above manner, whether or not paper A is loaded can be detected.

In addition, in the above embodiment, the support shaft 1 of the lever body 13
31, 131 Bearing grooves 112, 112 for receiving the parts are provided on both sides of the notch 111 of the paper guide 11, but it is possible to eliminate the bearing grooves 112, 112 and make both sides of the notch flat. As shown in FIG. 4, the intermediate portions of both sides 151, 151 of the presser plate 150 are bent into a substantially Ω shape to form bearing portions 156, 156, and these bearing portions 156, 156 support the support shaft of the lever body 13. 131,1
31 may be held with a press.

The presser plate 15 can be easily removed by reversing the fitting operation described above. The lever body 13 can be easily taken out from the paper guide 11 by pulling it out from the notch 111 after removing the presser plate 15.

As described in detail, according to the present invention, at the same time as the lever body is attached to the paper guide, a biasing force is applied to the lever body by the leaf spring provided on the presser member that holds the lever body. Further, the presser member can be easily attached to the paper guide by simply attaching it.

Therefore, there is no longer a need for a separate spring that applies a biasing force to the lever body, or for screwing the presser member to the paper guide, which was required in the past, and the structure of the lever body is simplified. The work becomes easier, and the efficiency of assembly work can be further improved.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a paper presence/absence detection device according to the present invention, and FIG.
The figure is an exploded perspective view of the main parts, FIG. 3 is a 4111 cross-sectional view showing the main parts in an assembled state, and FIG. 4 is a perspective view showing another example of the presser plate, which is the main part. 11...Paper guide, 13...Lever body, A...Paper, 14...Photoelectric sensor, 15...Press plate (presser parts), 154...
...Plate spring (part), 10...Platen, 131... Support shaft, 152... Bent part, 155... Locking claw part. Patent applicant: NEC Home Electro Fig. 1 Fig. 2 Fig. 3

Claims (1)

[Claims] (1) One end of the lever body provided on the paper guide is biased in one direction facing the paper feed path, and this lever body is rotated in the other direction by the paper loading operation, and the rotation operation determines whether or not the paper is loaded. In the device for detecting, a plate spring that biases the lever body in one direction is integrally provided with a presser member that holds the lever body on the paper guide, and the presser member can be fitted into and removed from the paper guide. A paper presence/absence detection device for a printer, characterized in that: