JP3268523B2 - Flatbed type document reader and document cover - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flatbed type document reading apparatus widely used in an OCR (optical character reader), an image reading apparatus, a copying machine and the like, and a structure of the document cover. And a document cover that incorporates a light source lamp therein to enable reading of a transparent document.

[0002]

2. Description of the Related Art A flat bed type document reading apparatus is provided with a transparent platen made of a glass plate or the like on the upper surface of an apparatus housing, and a document placed on the transparent platen is moved under the transparent platen. It is read by a moving optical reading unit and has a press plate that makes the original adhere to the transparent platen in order to prevent the original from rising from the transparent platen during reading due to folding or bending of the original. Document cover is provided.

A flat-bed type document reading apparatus capable of reading a transparent document requires a light source lamp to be built in a document cover. 9 and 10 show an example of an apparatus having such a structure. A reading unit 41 that runs along the lower surface of the transparent document table 12 is built in the apparatus main body 3, and the document cover 1 The lamp unit 8 which runs along the upper surface of the holding plate 7 is built in. Inside the reading unit 41, a light source lamp 73 for illuminating a reflection original, a reflection mirror 74, an imaging lens 75, and an image sensor 7 are provided.
6 is connected to, for example, a traveling drive belt 77 as shown in FIG. 10, and travels while being guided by a guide rod 42 and a guide rail 70 mounted in the apparatus main body.

On the other hand, the lamp unit 8 in the document cover is
A light source lamp 78 for illuminating the transmissive document 13 is provided. The light source lamp 78 travels along the guide rail 43 provided on the cover plate 2 in accurate synchronization with the reading unit 41. In the illustrated device, a rack 44 (see FIG. 2) is provided on the back surface of the guide rail 43 on the cover plate side in FIG. 10, and a pinion 45 meshing with the rack 44 is mounted on the lamp unit 8, and the light source unit 8 with built-in motor
The vehicle is driven by rotating the vehicle.
As the light source lamp 78 on the original cover 1 side, in order to make the original cover 1 as thin as possible with good operability, a thin one is used, and a fluorescent tube having a diameter of several mm is often used. When the light source lamp 78 is incorporated in the document cover, a transparent plate or a white translucent plate is used as the holding plate 7. The transparent plate is of course excellent in terms of light transmittance, but a white translucent plate is often used because diffused and uniform light can be obtained.

[0005]

In the structure in which the lamp unit 8 for reading the transparent original is built in the original cover, an error in the parallelism between the lamp unit 8 and the reading unit 41 when viewed in a plan view becomes a problem. Become. For example, as shown in FIG. 11 (the drawing is exaggerated), when the document cover 1 and the apparatus main body 3 are displaced, the lamp unit 8 guided by the document cover and the reading unit guided by the apparatus main body. A shift occurs in the degree of parallelism with the unit 41. In particular, when a light source lamp having a small diameter is used and the holding plate 7 is made of a transparent plate,
At a position where the optical axis 8 is deviated from the reading line 79, the illuminance is greatly reduced (for example, a solid line in FIG. 12), which causes a problem that uniform reading in the width direction of the document cannot be performed.

Therefore, conventionally, the illumination light is diffused by using a white translucent plate as the holding plate 7 so that the illuminance does not fluctuate due to the displacement between the light source lamp 78 and the reading line 79. When a translucent plate is used, FIG.
As indicated by a dashed line in FIG. 2, the illuminance is reduced as compared with the case where a transparent plate is used. Therefore, it is necessary to use a light source lamp having a larger diameter to increase the amount of light, or the reading speed is reduced. There was a problem.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-described problems. In a flatbed type document reading apparatus having a structure in which a light source lamp for reading a transparent document is built in a document cover, the present invention is directed to a light source lamp. An object of the present invention is to provide a document cover capable of performing clearer and more uniform reading by keeping the axis from deviating from a reading line.

[0008]

According to the first to third aspects of the present invention, there are provided claw 5 at both ends of a lamp unit guide 43 for guiding a lamp unit 8 built in document cover 1.
3 and 53, and when the document cover 1 is closed,
3 and 53 are fitted to both ends of the reading unit guide 42 on the apparatus main body side, so that the reading unit 41 and the document cover side lamp unit 8 caused by a positional error or loose movement between the apparatus main body and the document cover. Is prevented from shifting.

That is, the invention of claim 1 of the present application incorporates a lamp unit 8 for reading a transparent document which faces the reading unit 41 on the device body side with the transparent document table 12 provided on the upper surface of the device body 3 interposed therebetween. In the document cover 1 of the flatbed type document reading apparatus, claws 53 projecting toward the apparatus main body are provided at both ends of a lamp unit guide 43 for guiding the lamp unit 8.
Reference numeral 3 denotes a reading unit guide 42 provided on the apparatus main body when the document cover 1 is covered with the transparent document table 12.
Are provided with fitting portions 52 fitted to both ends.

According to a second aspect of the present invention, in the first aspect of the present invention, the pawl 53 is provided rotatably around an axis parallel to the guide direction of the lamp unit guide 43, and the fitting portion 52 of the pawl is provided. A spring 5 that is provided in a shape that can be fitted and disengaged in a tangential direction when rotating and that urges the claw 53 in the fitting direction.
6 and a cover opening lever 58 for rotating the claw 53 in a direction in which the fitting portion 52 is disengaged when a force is applied upward.

According to a third aspect of the present invention, the claw 53 of the first aspect is formed of an elastic material such as a plastic plate or a spring plate, and the fitting portion 52 is provided with a locking function by the elasticity of the claw 53 itself. Things.

In the structure provided with such claws 53, an opening 54 into which these claws 53 are inserted must be provided on the upper surface of the apparatus main body. According to a fourth aspect of the present invention, there is provided a flat bed type document reading apparatus provided with the document cover 1 provided with the claws 53, wherein an opening 54 for inserting the claws 53 is provided on an upper surface of the apparatus main body. Spring 6 on 54
A cover member 62 is provided, which is urged in the closing direction by 3 and pushed downward by the claw 53 to rotate downward.

[0013]

According to the first to third aspects of the present invention, the direction of the lamp unit guide 43 provided on the document cover side is defined by the reading unit guide 42 provided on the apparatus main body side. A shift in parallelism between the lamp unit 8 and the reading unit 41 due to accumulation of dimensional errors can be prevented.

According to the second and third aspects of the present invention, the closed state of the document cover 1 is locked by a claw 53 for defining the direction of the lamp unit guide 43. When the cover release lever 58 is lifted, the pawl 53 rotates and the lock is released, and the document cover 1 is opened. Further, in the structure of the third aspect, the force is applied to the document cover 1 and the document cover 1 is lifted upward, so that the claw 5 is lifted.
The lock by the elasticity of 3 is released, and the document cover 1 is opened.

According to the fourth aspect of the present invention, the opening for inserting the claw 53 for defining the direction of the lamp unit guide 43 is automatically closed by the cover member 62 when the document cover 1 is opened. Therefore, the intrusion of dust and the like into the apparatus main body can be prevented, and when the document cover 1 is closed, the cover member 62 is automatically opened by the entry of the claw 53, so that the operation of opening and closing the document cover 1 can be complicated. Absent.

[0016]

1 to 3 show an embodiment of the first aspect of the present invention. As shown in FIG. 3, there is provided a reading unit 41 which runs along the lower surface of the transparent document table 12 on the top surface of the apparatus main body 3, and this reading unit 41 is a guide provided in the main body on the near side in FIG. It slides along the rod 42 (see FIG. 10). The document cover 1 is hinged to the main body 3 on the back side of the figure, a pressing plate 7 made of a transparent plate is provided inside, and a lamp unit 8 running along the back side of the pressing plate is provided. The lamp unit 8 is provided with a guide rail 43 provided on the near side of the original cover in the drawing.
(See FIG. 10). The guide rail 43 on the document cover side has a rectangular cross section, and a rack 44 is provided on one surface thereof, and a pinion 45 meshing with the rack is mounted on the lamp unit 8. Pinion 45
Is driven by gears 47, 48 and 49 by a pulse motor 46 mounted on the lamp unit 8. On the surface of the guide rail 43 opposite to the surface on which the rack is provided, slide shoes 51 provided on the ramp unit 8 are pressed at positions on both sides of the rack engagement position. The direction of the lamp unit 8 is defined by the two slide shoes 51.

At both ends of the guide rail 43, fitting grooves 52 are provided.
Are formed integrally with each other. The fitting groove 52 of the claw is formed in an arc shape centered on the pivot shaft of the document cover 1 and has a groove width just fitted to the guide rod 42 of the reading unit. Have. An opening 54 is provided in a portion of the upper surface of the apparatus facing the claw 53, and both ends of the guide rod 42 are located immediately below the opening 54. When the document cover 1 is closed, the guide rod 42 of the reading unit is fitted into the fitting groove 52 of the claw 53 as shown in FIG. 1, so that the guide rail 43 of the lamp unit 8 is parallel to the guide rod 42. Positioned.

FIGS. 4 and 5 show an embodiment of the second aspect of the present invention. In this embodiment, the guide rail 43 of the light source unit has a shaft 5 parallel to its guide direction.
5 is penetrated, and a claw 53 having a hook-shaped fitting groove 52 at the end at the both ends of the shaft 55 is fixed. The fitting groove 52 is opened to the side of the claw 53, and a winding spring 56 for urging the claw 53 toward the opening side of the fitting groove is provided. A guide oblique side 57 is formed on the distal end side of the portion where the fitting groove 52 is open. A cover opening lever 58 is formed integrally with one of the claws 53 and extends toward the side of the document cover.

4 and 5, when the document cover 1 is closed, the pawl 53 penetrates the opening 54 shown in FIG. 3, and the guide oblique side 57 at the tip comes into contact with the guide rod 42 of the reading unit. After slightly swinging rightward in FIG. 4, the guide rod 42 is fitted into the fitting groove 52. In this state, the guide rod 42 and the fitting groove 52 are fitted by the urging force of the winding spring 56. In this state, the direction of the guide rail 43 is regulated by the guide rod 42, and the closed state of the document cover 1 is changed. Locked. When the cover release lever 58 is lifted in this locked state, the pawl 53 swings rightward in FIG. 4 and the guide rod 42 and the pawl 53 are disengaged from each other. Released by

FIGS. 6 and 7 show an embodiment of the third aspect of the present invention. In this embodiment, the tip of the fitting groove 52 of the claw 53 provided in the same manner as in FIG.
Is made elastic. In this structure, when the document cover is closed, the guide rod 42 on the main body side is fitted into the fitting groove 52 of the claw 53, and the fitted position is held by the elastic gripping force of the claw 53. This structure is shown in FIGS.
Similarly to the above, the claw 53 is also used as a lock mechanism for the document cover 1, but has a feature that the structure can be simplified.

FIG. 8 shows a fourth embodiment of the present invention. A pin 61 is mounted so as to cross the opening 54 of the main body shown in FIG. 3 and a cover member 62 pivotally supported at one end to the pin 61 is provided.
Is provided. When the upper surface of the cover member 62 is in the horizontal position, the opening 5
4 abuts against a locking flange 64 provided on the edge of the fourth. When the document cover 1 is open, the cover member 62 is
The opening 54 is closed by moving upward by the urging force of No. 3.
On the other hand, when the document cover 1 is closed, the claw 53 inserted into the opening 54 pushes the cover member 62 downward, thereby opening the opening 54 and inserting the claw 53 into the main body 3.
The guide rod 42 is located just below the opening 54.

[0022]

According to the present invention described above, the fluctuation at the time of closing the document cover due to various errors occurring between the document cover and the apparatus main body is corrected, and the lamp unit provided on the document cover side is corrected. It is possible to prevent a deviation from the reading unit on the apparatus main body side.

Therefore, according to the structure of the present invention, it is possible to obtain a flat-bed type document reading apparatus capable of reading clearer and more uniform documents, and to use a light source lamp having a small diameter as a light source lamp for reading a transparent document. Even when a lamp is used, the pressing plate can be a transparent plate, and the reading speed can be improved.

[Brief description of the drawings]

FIG. 1 is a side view of an essential part showing an embodiment of the invention of claim 1;

FIG. 2 is a schematic plan view of FIG.

FIG. 3 is a schematic perspective view showing an embodiment of the invention of claim 1;

FIG. 4 is a side view of an essential part showing an embodiment of the invention of claim 2;

FIG. 5 is a perspective view of a main part showing an embodiment of the invention of claim 2;

FIG. 6 is a side view of an essential part showing an embodiment of the invention of claim 3;

FIG. 7 is a side view showing a state where the cover of FIG. 6 is opened;

FIG. 8 is a side view of an essential part showing an embodiment of the invention of claim 4;

FIG. 9 is a cross-sectional view of a main part of a flat bed type document reading apparatus capable of reading a transparent document.

FIG. 10 is a perspective view of a portion shown in FIG. 9;

FIG. 11 is a schematic plan view showing the displacement between the cover and the main body.

FIG. 12 is a graph showing a sensor output value with respect to a lamp light amount when a white translucent plate is used.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Original cover 2 Cover plate 3 Main body 7 Holding plate 8 Lamp unit 12 Transparent platen 13 Original 41 Reading unit 42 Guide rod 43 Guide rail 52 Fitting groove 53 Claw 54 Opening 58 Cover release lever 62 Cover member 63 Winding spring

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-125060 (JP, A) JP-A-61-49555 (JP, A) JP-A-61-124934 (JP, A) JP-A-7-125 56248 (JP, A) Fully open 58-96557 (JP, U) Fully open 63-51334 (JP, U) Fully open 63-185349 (JP, U) Fully open 4-124248 (JP, U) (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 1/04-1/207

Claims (4)

(57) [Claims] 1. A transparent platen provided on an upper surface of an apparatus body (3).
The lamp unit (8) is guided in the document cover of the flatbed type document reading device that has the built-in lamp unit (8) for reading the transparent document facing the reading unit (41) on the device body side with the (12) in between. Lamp unit guide (4
3) are provided at both ends with claws (53, 53) protruding toward the apparatus main body. These claws (53, 53) are provided when the document cover (1) is covered on the transparent document table (12). And a fitting unit (52) fitted to both ends of a reading unit guide (42) provided in the apparatus body. 2. The lamp unit guide (43), wherein the pawl (53) is a lamp unit guide (43).
Provided rotatably around an axis parallel to the guide direction of
A fitting portion (52) of the claw is provided in a shape that can be fitted and disengaged in a tangential direction at the time of its rotation, and a spring (56) for urging the claw (53) in the fitting direction, and an upward force is applied. Mating part when added
The document cover according to claim 1, further comprising a cover opening lever (58) for rotating the claw (53) in a direction in which the (52) is detached. 3. The claw (53) is formed of an elastic material,
2. The document cover according to claim 1, wherein the fitting portion (52) is provided with a lock function by the elasticity of the elastic material. 4. The flatbed type document reading apparatus provided with the document cover (1) according to claim 1, further comprising an opening (54) on the upper surface of the apparatus main body, into which the claw (53) is inserted. ) Is biased in the closing direction by a spring (63), and the cover member (62) is rotated downward by being pushed by the claw (53).
A flat-bed type document reading apparatus, wherein: