JPH0652925B2 - Input/Output Devices - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an input/output device such as a facsimile.

(Prior Art) A facsimile machine in which a single feed roller is provided for both transmission and reception (see Japanese Utility Model Publication No. 58-22353)
or a unit with an integrated transmitting and receiving head (JP Patent Publication 56-3427
(See Publication No. 3). In this case, however, the transport paths for the document and the recording paper are separate, making the device large and complicated in configuration. There are also examples where the transport paths are partially shared, but there are no examples where the device is combined with an integrated head to achieve compactness. Also, a sensor is provided between the roll paper holder and the recording unit to detect the presence or absence of recording paper (end detection) and the amount of remaining paper, which causes the problem of high costs.

(Objective of the Invention) The present invention has been made to improve upon the problems of the prior art described above, and aims to provide an input/output device which promotes the sharing of functional parts between document reading and recording operations, thereby realizing a simplified configuration, a more compact device, and lower costs, as well as reducing power consumption during recording operations.

(Configuration of the Invention) In order to achieve the above object, the input/output device of the present invention comprises a reading unit that reads a document, a recording unit that records image information on recording paper, transport rollers that transport the document and recording paper, a head unit that positions the reading unit on the upstream side in the transport direction and the recording unit on the downstream side, a light source unit consisting of a plurality of light sources that illuminate the reading position when reading the document, and a lighting control unit that selectively turns on light sources among the light source unit, and is configured so that during recording, only specific light sources are turned on by the lighting control unit, and the reading unit detects the condition or shape of the recording paper.

According to the above-mentioned configuration, one transport roller is used for transporting both the document and the recording paper, and the reading unit is disposed on the upstream side in the transport direction and the recording unit is disposed on the downstream side, so that the state or shape of the recording paper can be detected by the reading unit.
This helps save power and prevent the head unit from overheating.

(Embodiments) Hereinafter, embodiments will be described in detail with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which 1 is a document table, 2 is a separation roller, 3 is a separation piece, 4 is a recording paper roll, 5 is a delivery roller, 6 is a tension roller, 7 is a
denotes a feed roller, 10 denotes a head unit formed by integrating the reading section 8 and the recording section 9, 11 and 12 denote a fixed blade and a rotary blade that form a cutter, 13 denotes a discharge roller, 14 denotes a tension roller, and 15 denotes a stacker.

Next, the operation of this embodiment will be described. The originals are separated and drawn out one by one from the original table 1 by the separation roller 2 and the separation piece 3, read by the reading unit 8, and then discharged to the stacker 15 by the discharge roller 13. At this time, the head unit 10 moves leftward by a distance of 1/2, or the feed roller 7 moves rightward by the same distance, so that the reading unit 8 comes into proper contact with the feed roller 7 and reading becomes possible. The cutter does not operate. On the other hand, for recording, since the leading edge of the recording paper drawn out from the recording paper roll 4 is between the feed roller 5 and the feed roller 7, when a recording signal is received, the paper is fed into the recording unit 9 by the feed roller 7. After recording, the paper moves further, is cut by the cutter, and is discharged to the stacker 15 by the discharge roller 13. At this time, the head unit 10 moves rightward by a distance of 1/2, or the feed roller 7 moves leftward by the same distance, so that the recording unit 9 comes into proper contact with the feed roller 7 and recording becomes possible. The cut, blank recording paper is pulled back to its initial position by the feed roller 7 and the delivery roller 5. The drive system is not shown in the figure.

In the present embodiment configured as described above, the head unit 10, which is an integral combination of a reading section (contact sensor) and a recording section (thermal head), and the feed roller 7, which is an integral combination for reading and writing, are displaced by a small distance relative to each other.
Reading and recording are both possible, and the transport path and transport drive system can be shared, resulting in significant cost reduction and miniaturization.

Fig. 2(a) shows the mechanism for displacing the feed roller 7. The position of the feed roller 7 shown by the solid line is the position during recording, and the dashed line is the position during reading. Solenoid
The attraction of the solenoid 16 pulls the lever 18 against the biasing force of the compression spring 17, causing the lever 18 to rotate about a fulcrum 19, displacing the feed roller 7 and switching from the recording section to the reading section. In order to facilitate the movement of the feed roller 7 during switching, the solenoid 20 may be attracted to lift the head unit 10 against the biasing force of the compression spring 21.
When a document or recording paper is received, it is sucked in and the head unit
The purpose of this is to temporarily lift 10 and ensure that the document and recording paper are gripped, but this may not be necessary depending on the contact pressure, transport force, and other conditions.

2(b), the drive system for roller 7 transmits the rotation of a motor (not shown) via belt 26 to an integrated pulley 28 and gear 29 rotatably supported on fulcrum shaft 27, and the rotation is then transmitted to gear 31 fixed to feed roller shaft 30 to rotate feed roller 7. When feed roller 7 is displaced to the reading section side or the recording section side, gear 31 meshes with gear 32 or 33, and the rotation of these gears drives, for example, separation roller 2 and feed roller 5.

Fig. 3 shows a mechanism for displacing the head unit 10 in the opposite manner to Fig. 2. The attraction of the solenoid 22 pulls the lever 24 against the biasing force of the compression spring 23, causing the lever 24 to rotate about the fulcrum 25, displacing the head unit 10 and switching it from the reading section to the recording section. Note that a motor and a cam may be used instead of the solenoid to move the lever.

FIG. 4 shows the basic configuration of the head unit 10, in which a read driver circuit 34 and a record driver circuit 35 are provided.

In conventional devices, the recording paper transport path leading to the recording unit is generally provided with a required number of paper sensors to detect the presence or absence of recording paper, whether the recording paper is jammed, and, in devices that can use recording paper of different sizes, the shape and size (paper width) of the recording paper.
However, in recent years, as the demand for smaller size, lighter weight, and lower cost has progressed, restrictions on the installation location of these sensors have become stricter, making it difficult to mount wiring and connectors for power supply and signal extraction, as well as their mounting members, etc. Furthermore, problems arise in the ease of assembly, adjustment, etc. In the present invention, by locating the reading unit on the upstream side of the transport path as described above, the recording paper can be detected by the reading unit, eliminating the need to provide a dedicated sensor for recording paper detection as in the past.

However, when detecting or reading various conditions of a recording paper with a reading unit, strict accuracy is not required compared to when reading detailed information of a document.
While reading with a resolution of one line per mm is required, with recording paper, it is sufficient to be able to detect the presence or absence, skew, and relatively large characters and marks such as air end marks printed on the recording paper, and this level of detection is sufficient.

When reading an original, it is necessary to perform image processing or image processing on the signal level (analog signal) from the reading sensor to faithfully reproduce the information, but in the case of recording paper, it is sufficient to have the performance required to detect it. There is no change in the signal level (analog signal) from the reading sensor when detecting or reading recording paper. However, in the case of letters, marks, etc., there is a change in level, but resolution is not required. Therefore, even if the performance of the reading section is somewhat reduced when reading recording paper, it is still possible to detect recording paper.

In the present invention, the image signal processing or image processing circuit for binarizing the signal level (analog signal) from the sensor of the reading section is commonly used whether reading an original or detecting a recording paper.

Considering the above conditions, in the present invention, only a few specific light sources among the multiple illumination light sources provided in the reading section are always turned on, and the recording paper conveyed during the recording operation is detected by illumination from these specific light sources. In addition, when reading an original, all the light sources are turned on.

First, in conventional contact sensors, LE is used as the light source for illumination.
D (light-emitting diodes) are used, and the illumination is provided for the required length (one scan line length) along the main scan line of the document. This one line is composed of N blocks of LED groups as shown in Figure 5 (a), and each block has n LEDs connected in series as shown in Figure 5 (b). When an on signal is given to the base of transistor Q1, the transistor Q1 becomes conductive, power is supplied, and all the LEDs light up.

As shown in FIG. 6, there are two sensors on each side of the sensor.
Some also feature groups of LEDs.

The presence or absence of recording paper can be detected by detecting a specific spot on the recording paper. Therefore, when the recording paper passes under the reading section, if only the LEDs in a specific block on the inside of both ends of the width of the recording paper among the 1 to N blocks of the LED group are lit, the sensor will read it by that illumination.
The presence or absence of recording paper can be determined. FIG. 7 shows the configuration of a light source and its driving circuit in one embodiment of the present invention. In this example, the c, e, k blocks of 1 to N are
This is a circuit that constantly lights up the three blocks above. When the device is turned on, the necessary voltage (Vcc) is supplied from the power supply unit, and blocks c, e, and k are lit, and as long as voltage is being supplied, those blocks remain lit. Next, when reading an original, it is necessary to light up all of blocks 1 to N, but since blocks c, e, and k are already lit, the other blocks are lit. To do this, an on signal is applied to the base of transistor Q1, which supplies voltage to all the LEDs in the other blocks, causing them to light up.

If the light emission amount of the light source in each block c, e, and k is not approximately the same as that of each light source in other blocks, the illuminance on the document surface will not be uniform, and the signal level of the reading sensor will be, for example, as shown in Figure 8. In Figure 8, the illuminance is low in parts c and e, and high in part k. In order to prevent such variations from occurring, it becomes necessary to use LEDs with the same number of LEDs and characteristics in each block, and
The values of resistors R1 and R2 are appropriately selected so that the amount of light emitted for each block is approximately uniform. The uniformity of the amount of light emitted can be measured using a measuring tool, but it is also possible to check the flatness of the signal using a test chart (a special document for checking the flatness of the signal level) or the like in the input device that reads the document. The values of R1 and R2 should be appropriately selected so that the level difference of the signal flatness falls within a range that does not affect the image signal processing.

Fig. 9 and Fig. 10 respectively show a light source and its driving circuit according to another embodiment of the present invention. The one in Fig. 9 is configured with a circuit for compensating for the voltage drop between the collector and emitter of the transistor Q1 in Fig. 7, and with resistor R1 in common. Diode D may be a transistor. Also, the one in Fig. 10 is configured so that the anode side common line of the c, e, k blocks connected to resistor R2 provided in the head unit in Fig. 7 can be controlled from outside the head unit.

In general, input/output devices require a lot of power when recording, and if the reading unit is operated at the same time as recording, even more power is required, which causes the temperature of the head unit to rise, and heat countermeasures such as the shape and size of the heat sink and a cooling fan become difficult. In addition, the load on the power supply is also large, which affects the size and capacity. As in the above embodiment, turning on a specific light source in the reading unit and detecting the recording paper by that illumination is very effective in reducing power consumption and countermeasures against heat.

As described above, according to the present invention, a single transport roller is used to transport both the document and the recording paper, and a head unit is provided with a reading section on the upstream side of the transport direction and a recording section on the downstream side, and the reading section detects the state or shape of the recording paper, eliminating the need for a paper sensor as previously provided, and therefore eliminating the need for wiring members and assembly processes required for this, resulting in a significant cost reduction through reduced number of parts and reduced mounting man-hours. Also, when detecting the recording paper, the light source in the light source section is selectively turned on, reducing power consumption while maintaining the required performance, thereby saving power and preventing the head unit from overheating.

[Brief description of the drawings]

FIG. 1 is a diagram of an embodiment of the present invention, FIG. 2 is a diagram of a feed roller displacement mechanism and a drive system for the feed roller in the same embodiment, FIG. 3 is a diagram of a head unit displacement mechanism in another embodiment, FIG. 4 is a diagram of a head unit, FIG. 5 is a diagram of an illumination light source for a contact sensor, FIG. 6 is a diagram showing another example of an illumination light source, FIG. 7 is a diagram of an illumination light source and its drive circuit in an embodiment of the present invention, and FIG. 8 is a diagram showing the variation in signal level caused by the difference in the amount of light emitted between a specific light source that is always on and other light sources.
9 and 10 are diagrams showing the configuration of an illumination light source and its drive circuit in another embodiment, respectively. 1: original table, 2: separation roller, 4: recording paper roll, 5: delivery roller, 7: feed roller, 8: reading section, 9: recording section, 10: head unit, 13: discharge roller, 15: stacker, 16, 20, 22: solenoid.

Claims (1)

[Claims] [Claim 1] An input/output device comprising: a reading unit which reads an original; a recording unit which records image information on recording paper; transport rollers which transport the original and the recording paper; a head unit which positions the reading unit on the upstream side in the transport direction and the recording unit on the downstream side; a light source unit consisting of a plurality of light sources which illuminate a reading position when the original is read; and an illumination control unit which selectively turns on light sources among the light source unit, wherein during recording, only specific light sources are turned on by the illumination control unit, and the state or shape of the recording paper is detected by the reading unit.