JPH05187161A - Lock mechanism for moving section - Google Patents

Abstract

PURPOSE:To improve the function by pivotally fitting a moving section to a fixed section via a horizontal shaft, providing a moving section opening direction energizing means and a closed position locking means, and providing a means energizing the moving section in the opening direction at the final stage of a closing action. CONSTITUTION:A moving section 2 is openably or closably fitted to a fixed section 1 while the horizontal rotary center O1 serves as a fulcrum. A gas spring 3 is provided between the fixed section 1 and the moving section 2 to energize the moving section 1 in the opening direction. A locking means 4 closing the moving section 2 to the fixed section 1 is provided. A backing 5 is protruded on the fixed section 1, and it is energized upward by a coil spring 8. The energizing force of the spring 8 is added to the spring back force of a spring 3 at the final stage of the closing action of the moving section 2. When a lock system requiring large spring back force such as a detent system is locked, the moving section 2 can be precisely positioned, and the moving section 2 can be easily pulled down at the time of the closing action.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lock mechanism for a movable part which is used in an optical character reader or the like and can be opened and closed with a horizontal rotation center axis as a fulcrum.

[0002]

2. Description of the Related Art In recent years, an optical character reading device has mainly been a front operation type design, and since it is easy to perform operations such as taking out a jam sheet, a large sheet is placed under a sheet guide so that a medium conveying surface can be easily reached. Side, upper side (conveyor roller drive side,
On the driven side), a structure is required in which the fixed part and the movable part are separated. In this structure, from the viewpoint of ease of opening and closing, it is desirable that the movable part is pushed only when it is closed, and the release lever is operated and then pulled when it is opened.

By the way, in the optical character reader, since the fulcrum for opening and closing the movable part is the horizontal axis, gravity acts on the movable part in the closing direction, and the closed movable part is locked with the detent mechanism. Considering the positional accuracy when locked by the means, a large back spring force is required (sufficient back spring is necessary to reliably lock the movable portion at a predetermined position). This back spring force is applied by elastic connecting means such as a gas spring provided between the fixed portion and the movable portion.

[0004]

However, when the back spring force becomes large, a force is required to operate the detent mechanism of the locking means when the movable part is closed, so that the force required to close the movable part increases. The operation is not easy. On the contrary, when the back spring force of the gas spring is small, the movable part is easily closed, but the upward locking force of the gas spring in the lock closed state is small.
The position accuracy of the closed movable part deteriorates.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a movable portion locking mechanism which can close a movable portion easily and can accurately position the movable portion in a locked state.

[0006]

In order to achieve the above-mentioned object, in the present invention, the fixed portion is configured to support the movable portion so as to be openable and closable about a horizontal rotation center as a fulcrum. In a device provided with an elastic connecting means for urging the movable portion in the opening direction between the two, a locking means for locking the movable portion in a closed position is provided, and the movable portion is movable at the end of the closing operation of the movable portion. A biasing means for biasing the portion in the opening direction is provided on the fixed portion side.

[0007]

The urging means urges the movable portion in the opening direction at the end of the operation of closing the movable portion. Therefore, even if the elastic connecting member has a small back spring force, the reduced amount can be compensated by the urging force of the urging means, and the movable portion closing operation can be easily performed. Further, when the movable portion is closed, the biasing force of the biasing means acts in the moving portion opening direction in addition to the back spring force of the elastic connecting member (the biasing force of the biasing means compensates for the decrease in the back spring force). The movable part can be reliably locked with good positional accuracy.

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

1A and 1B are structural explanatory views of the optical character reading apparatus of the present embodiment. FIG. 1A shows a closed state and FIG. 1B shows an open state. In the figure, 1 is a fixed part, 2 is a movable part, 3 is a gas spring (elastic connecting member), 4 is a locking means, and 5 is a backing which is a reading reference.

The fixed part 1 is provided with a drive system 6 including a drive source and a plurality of drive rollers, a roller pin 7 for locking when the movable part 2 is closed, a backing 5 and the like. It is biased upward by a coil spring (biasing means) 8. The movable part 2 is provided with a plurality of driven rollers 9 corresponding to the rollers of the fixed part, a fluorescent lamp unit 10 for illuminating the original, a locking means 4, etc., and the backing 5 faces the fluorescent lamp unit 10. is doing. The gas spring 3 has a fixed portion 1
It is provided between the movable part 2 and the movable part 2, and urges the movable part 2 in the opening direction. The structure of the lock means 4 will be described below with reference to FIG.

The locking means 4 includes a support plate 11 (see FIG. 1) fixed to the movable portion 2 side, and a pin 11a on the support plate 11.
The cam 12 is rotatably supported via the detent mechanism 13, and the release lever 14 is rotatably supported on the support member 11 about the rotation center O ₂ . The detent mechanism 13 includes a lever 15 swingably supported by the support plate 11 via a pin 11b, a detent member 16 supported by the tip of the lever 15, and a spring 17 for urging the lever 15 clockwise. It is composed of.

In the open state in which the movable part 2 is rotated in the direction of arrow A in FIG. 1 (A) about the center of rotation O ₁ as a fulcrum to the position indicated by the chain line, the backing 5 has a coil spring as shown in FIG. It is biased by 8 and protrudes. Further, in this state, the cam 12, the release lever 14, and the detent member 16 are in the states shown in FIG.
6 is engaged with the recess 12d of the cam 12, and the protrusion 14a of the release lever 14 is disengaged from the recess 12c of the cam 12.

When the movable part 2 is rotated in the direction of arrow A'from this state, the movable part 2 is compressed while compressing the gas spring 3.
3 and the frame of the movable part 2 finally pushes down the backing 5 against the urging force of the coil spring 8 and then the frame of FIG.
It is positioned at the position (B) (the position shown in FIG. 1A).

At the end of the rotation of the movable portion 2, one end 12a of the cam 12 engages with the roller pin 7, and the cam 12 rotates clockwise in FIGS. Then, when the movable portion 2 is closed, as shown in FIG. 2A, the concave engagement portion 12e between the one end 12a and the other end 12b of the cam 12 engages with the roller pin 7, and the projection 14a is a recess 12
c and the detent member 16 engage with the recess 12f, respectively, and the cam 12 is locked in this state.

Thus, at the end of the closing operation of the movable portion 2, the back spring force of the gas spring 3 is added to the biasing force of the coil spring 8, so that the back spring force of the gas spring 3 facilitates the opening operation of the movable portion. Therefore, the movable portion 2 is precisely positioned in the closed state even if it is made small.
Further, when the movable part 2 is closed, the backing 5 is pressed against the frame of the movable part 2 by the urging force of the coil spring 8. Therefore, the optical path length from the fluorescent lamp unit 10 to the backing 5 is accurately ensured. ..

When the movable part 2 is opened from the locked state, the release lever 14 is rotated counterclockwise in FIG. 2 about the rotation center O ₂ . As a result, the protrusion 14a becomes the recess 1
Remove from 2c. After that, when the movable part 2 is lifted and opened,
The cam 12 has the other end 12b and the roller pin 7 engaged with each other.
2 by a predetermined amount in the counterclockwise direction, the recess 12d of the cam 12 engages with the detent member 16 as shown in FIG.
The cam 12 is held in this state.

At the initial stage of the opening operation of the movable part 2, the coil spring 8 plays a role of assisting the opening, and the opening is easily performed.

When reading characters and the like of a document by the optical character reading device of FIG. 1, the document is inserted into the device through the insertion section. The inserted document is conveyed by the drive system 6 and the driven roller 9 and discharged to the stacker. When the document passes over the backing 5, the fluorescent lamp unit 10 irradiates the document surface to read it. Done.

In the above description, an example has been described in which the role of the biasing means for biasing the movable portion upward together with the elastic connecting member is made to serve also as the coil spring for biasing the backing. Of course, a biasing means may be provided.

[0020]

As described above, according to the present invention, when the movable portion is closed, the elastic connecting member such as the gas spring and the urging means such as the coil spring urge the movable portion upward. Therefore, even if the back spring force of the elastic connecting member is reduced, the amount can be compensated by the biasing force of the biasing means, and the movable portion can be precisely positioned. Also, since the back spring force of the elastic connecting member is small,
The open moving part can be pulled down easily.

[Brief description of drawings]

FIG. 1 is a structural explanatory view of an optical character reader according to an embodiment of the present invention, FIG. 1 (A) showing a closed state and FIG. 1 (B) showing an open state.

2A and 2B are views for explaining the configuration and operation of the detent mechanism according to the embodiment of the present invention, in which FIG.
Shows the unlocked state of the movable part.

FIG. 3 is an operation explanatory view of the backing of the embodiment of the present invention, and FIG.
3A shows the movable portion open state, and FIG. 3B shows the movable portion closed state.

[Explanation of symbols]

 1 Fixed part 2 Movable part 3 Gas spring (elastic connecting member) 4 Locking means 5 Backing 8 Coil spring (biasing means)

Claims (1)

[Claims] 1. A fixed part (1) is supported by a movable part (2) so as to be openable and closable about a horizontal rotation center as a fulcrum, and between the fixed part (1) and the movable part (2). A device provided with an elastic connecting means (3) for urging the movable part (2) in an opening direction, wherein a locking means (4) for locking the movable part (2) in a closed position is provided, and the movable part (2) is provided. A lock mechanism for a movable part, characterized in that an urging means (8) for urging the movable part (2) in the opening direction at the end of the closing operation of (2) is provided on the fixed part (1) side.