JPH07322003A - Original travel path structure for original reader - Google Patents

Abstract

PURPOSE:To reduce the load of a driving means and to facilitate structure by transmitting driving force to a sensor roller only when an original is inserted between the sensor roller and a read means. CONSTITUTION:A first optical detector 58 detects the original 62, drives a motor 60 and transmits driving force to the sensor roller 55. Since the roller 55 is brought into contact with a direct read sensor 54 at that time and friction resistance exists, the meshing of a torque limiter 1 is slipped 86 only a gear 61 runs idle and the roller 55 does not rotate. When the tip of the original 62 reaches the read position of the sensor 54, reading is started. When the original 62 is fed and it reaches a place between the roller 55 and the sensor 54, friction resistance added to the roller 55 becomes small, torque added to the limitter 1 is reduced, they are meshed, torque is transmitted and the roller 55 rotates. The load of the motor 60 becomes friction resistance between the original 62 and the sensor 54, and it does not become the overload of the motor 60. Since a clutch is automatically switched by the load of the limitter 1, structure can be simplified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document reading device in a facsimile machine or the like, and more particularly to a structure of a document traveling path.

[0002]

2. Description of the Related Art A document reading device for reading the contents of a document written on paper or the like into data by means of optical means is used in various devices. Therefore, description will be made by taking an example of the one used in a facsimile machine. FIG. 3 is an explanatory view of the structure of a document traveling path in a conventional document reading apparatus used in a facsimile machine, and FIG. 4 is an enlarged view (FIG. 4 (a)) of an arrow A portion in FIG. 3 and its right side view ( Fig. 4 (b)). In the figure, reference numeral 50 is a running guide for guiding the travel of the original, 51 is an ADF roller that cooperates with the separate rubber 52 to feed the original one by one,
It is attached to an automatic paper feeder (not shown).

Reference numeral 52 denotes a first pinch roller 53, and a first pinch roller 53 for sandwiching the original document and sending the original document to a direct reading sensor side which will be described later.
A feed roller, 54 is a direct reading sensor for reading the contents of the original by optical means, 55 is a sensor roller provided facing the direct reading sensor 54 to form a background,
Reference numeral 56 is a second feed roller that cooperates with the second pinch roller 57 to send the document to the discharge side. Reference numeral 58 is a first photodetector for detecting that a document has been set, 59 is a second photodetector for detecting the document conveyed near the direct reading sensor 54, and 60 is each roller via a plurality of gears 61. Is a motor for driving. When the first photodetector 58 detects a document, the motor 60 receives the detection signal and drives it.

In the conventional facsimile apparatus configured as described above, the original 62 fed by the ADF roller 51 is driven by the motor 60 and the direct reading sensor 54 is driven by the first feed roller 52 and the first pinch roller 53. And the content of the original is read by the direct reading sensor 54. After that, the manuscript is the second
It is sent out to the discharge side by the feed roller 56 and the second pinch roller 57.

[0005]

However, in the case of the conventional document traveling path, the first feed roller 52, the first pinch roller 53, the second feed roller 56, and the second pinch roller 57 are used for feeding the document. Since many rollers are required, there is a problem that the structure becomes complicated and the cost becomes high. In order to reduce the load on the motor 60, a gap C shown in FIG. 4 (b) is provided between the sensor roller 55 and the direct reading sensor 54.
Needs to be adjusted in the manufacturing process so that the focus is not out of focus, and a step for adjustment is required, which increases the cost.

Therefore, in order to solve the above problems,
The first feed roller 52, the first pinch roller 53, the second feed roller 56, and the second pinch roller 57 are omitted, and the sensor roller 55 and the direct reading sensor 54 are arranged so as to come into contact with each other to detect the document feed. It is conceivable that the roller 55 is used. FIG. 5 is an explanatory view of such a document traveling path, and FIG. 6 is an enlarged view of an arrow A portion in FIG. 5 (FIG. 6 (a)) and a right side view thereof (FIG. 6 (b)). Is. In the figure, the same parts as those in FIG. 3 are designated by the same reference numerals.

In the case shown in FIGS. 5 and 6, the number of rollers can be reduced, but there are the following problems. When the original is set and the motor 60 is driven, the sensor roller 55
Starts to rotate, but the sensor roller 55 and the direct reading sensor 5
4 are in contact with each other (see FIG. 6 (b)), and the sensor roller is made of rubber, and the direct reading sensor 54 is glass, so that the friction coefficient between them is large and the sensor roller 55 rotates. Requires a large torque to drive the motor 6
The output of 0 must be increased. On the other hand, when the fed original is inserted between the sensor roller 55 and the direct reading sensor 54, the rotational torque of the sensor roller 55 becomes small because the friction coefficient between the paper and the glass is small.

That is, until the document is inserted between the sensor roller 55 and the direct reading sensor 54, the sensor roller 5
The motor having a large rotational torque must be selected only for rotating the motor 5, which results in unnecessary cost increase. In addition, the sensor roller 55
When the object comes into contact with the direct reading sensor 54 and rotates, it also causes generation of heat and noise, and there is also a problem of eliminating this.

[0009]

In a document reading apparatus according to the present invention, a document reading unit for reading the contents of a document by an optical unit and a background provided in contact with a document contact surface of the document reading unit. And a sensor roller for feeding an original by being rotated by the driving force transmitted from the driving means, and further including a rotation shaft of the sensor roller and a driving force transmission for transmitting the driving force of the driving means to the rotation shaft. It is provided with a clutch that connects the rotating shaft of the means.

[0010]

The clutch does not transmit the driving force to the sensor roller when the sensor roller and the document reading means are in contact with each other, but transmits the driving force when the document is inserted between the sensor roller and the document reading means. .

[0011]

1 is an explanatory view of a document traveling path in a document reading device of a facsimile apparatus according to an embodiment of the present invention, FIG.
2 is an enlarged view (FIG. 2 (a)) of an arrow A portion in FIG. 1 and a right side view (FIG. 2 (b)) thereof. In the figure, the same parts as those in FIG. In the figure,
Reference numeral 1 denotes a torque limiter attached to the rotary shaft of the sensor roller 55, which connects the rotary shafts of the sensor roller 55 and the gear 61. The other components and their arrangement are the same as in FIG.

The torque limiter 1 is a clutch having a structure in which the mesh is automatically disengaged with a predetermined torque or slips on a friction surface.
It has the function of transmitting torque again.
In this embodiment, attention is paid to the difference between the friction coefficient when rubber and glass come into contact with each other and the magnitude of the friction coefficient when paper comes into contact with glass. The torque limiter is arranged so that the rotation shafts of the sensor roller 55 and the gear 61 are disengaged from each other and the engagement torque is transmitted again when an original is inserted between the sensor roller 55 and the direct reading sensor 54. The torque of 1 is set.

Next, the operation will be described. When the original 62 is set and the first photodetector 58 detects it, the motor 60 starts rotating. The gear 61 rotates as the motor 60 rotates, and the rotational force is transmitted to the ADF roller 51 and the sensor roller 55. In this state, since the sensor roller 55 is in contact with the surface of the direct reading sensor 54, the gear 61 attached to the sensor roller 55 is disengaged from the torque limiter 1 due to frictional resistance.
Only the idler rotates, and the sensor roller 55 does not rotate. When the document 62 advances in the document traveling direction by the rotation of the ADF roller 51 and is detected by the photodetector 2, the motor 60 is temporarily stopped. Then, the motor 60 is driven again, and the number of rotations of the motor 60 is measured by the pulse counter, and the timing at which the leading edge of the original 62 reaches the reading position of the direct reading sensor 54 is determined based on this. Then, when it is determined that the leading edge of the document 62 has reached the reading position of the direct reading sensor 54, the reading by the direct reading sensor 54 is started.

When the original 62 is further fed and inserted between the sensor roller 55 and the direct reading sensor 54, the frictional resistance applied to the sensor roller 55 becomes small and the torque applied to the torque limiter 1 becomes small. The limiter 1 transmits the meshing torque, and the sensor roller 5
5 starts rotating. At this time, the load applied to the motor 60 is a frictional resistance between the original 62 and the surface of the direct reading sensor 54, and therefore the motor is not excessively loaded.

In this embodiment, the clutch switching is automatically performed by the load applied to the torque limiter, so that the structure of the device is simplified.

Further, the sensor roller 55 and the direct reading sensor 54
Since no gap is provided between the two, the process of adjusting the gap is omitted in the production process of the apparatus, and the cost can be reduced accordingly.

In the above embodiment, the torque limiter is used as the clutch, but the present invention is not limited to this. For example, an electromagnetic clutch may be used. In this case, the timing at which the original reaches between the sensor roller 55 and the direct reading sensor 54 is determined by the same method as the determination of the timing at which the leading edge of the original 62 reaches the reading position of the direct reading sensor 54 described in the above embodiment. The electromagnetic clutch may be driven based on this timing and the driving force may be transmitted to the sensor roller 55.

In the above embodiment, the case of the facsimile has been described, but the present invention is not limited to this, and any device other than the facsimile, for example, as long as it is a device for automatically feeding and reading an original, for example, It can also be applied to a document reading device that reads a document and inputs it as character data.

[0019]

As described above in detail, according to the present invention, the driving force is transmitted to the sensor roller when the document is inserted between the sensor roller and the document reading means. There is no heavy load on the means, and without increasing the output of the driving means more than necessary,
The structure is simple and the number of parts can be reduced. As a result, it is possible to obtain an original reading device that is inexpensive, compact, and has few failures.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a document traveling path in a document reading device according to an embodiment of the present invention.

2 is an enlarged view (FIG. 2 (a)) of an arrow A portion in FIG. 1 and a right side view thereof (FIG. 2 (b)).

FIG. 3 is an explanatory diagram of a structure of a document traveling path in a conventional document reading device used in a facsimile apparatus.

4 is an enlarged view (FIG. 4 (a)) of an arrow A portion in FIG. 3 and a right side view (FIG. 4 (b)) thereof.

FIG. 5 is an explanatory diagram of another document traveling path in the conventional document reading apparatus.

6 is an enlarged view (FIG. 6 (a)) of an arrow A portion in FIG. 5 and a right side view thereof (FIG. 6 (b)).

[Explanation of symbols]

 1 Torque Limiter 50 Travel Guide 51 ADF Roller 54 Direct Reading Sensor 55 Sensor Roller 60 Motor 61 Gear

Claims (3)

[Claims] 1. An original reading means for reading the contents of an original by an optical means, a background formed by being in contact with an original contact surface of the original reading means, and a driving force transmitted from a driving means. A sensor roller that rotates to send out a document; a rotation shaft of the sensor roller; and a clutch that connects a rotation shaft of a driving force transmission unit that transmits the driving force to the rotation shaft. The document path structure of the document reading device. 2. The document traveling path structure of the document reading device according to claim 1, wherein the clutch is a torque limiter. 3. A facsimile apparatus, comprising: the original document traveling path structure of the original document reading device according to claim 1; and a transmitting device for transmitting the read data.