JPS63122360A - Picture reader - Google Patents

Abstract

PURPOSE:To require no stepping motor or a linear motor using much power for a movement, to save a power and to attain a suitability to a portable machine using a battery by performing the movement for a reading scanning manually or by the use of a DC motor 9. CONSTITUTION:An optical system stored movable casing 2 is stored in an external casing 1. A speed is slowed down by plural gears connected to the DC motor 9 for moving the movable casing 2 to rotate a pulley 32 and move the movable casing 2 through wires 36, 39 wound on the pulley 32. One gear 25 of the gears is attached to a lever plate 26 rotating centering a fulcrum shaft 27, the level plate 26 is rotated by an operating thumb 30, a driving link from the DC motor 9 is disconnected to manually move the movable casing 2. A magnet drum 47 having plural magnetic poles is disposed on a circumference of the pulley 46 rotated by moving the movable casing 2, a magnetic resistance element 51 is disposed in the vicinity of the periphery of the magnet drum 47 to generate a pulse output by the movement of the movable casing 2 and picture information is fetched only when the pulse output is outputted.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention scans characters, images, etc. guided on a book or paper, and uses a one-dimensional image sensor (COD line sensor, etc.) to optically The present invention relates to an image reading device for reading electrical signals and converting them into communication signals for semiconductor buffer memories, recording media, computers, displays, printers, faxes, etc.

(Prior Art) Conventionally, an image scanner uses a stepping motor or a linear pulse motor as a driving source to move a reading device for scanning. In the case of a stepping motor, the foot rotation of the stepping motor rotates a pulley or gear press-fitted into the shaft, which is transmitted to a gear mechanism connected to this gear, a timing belt, or a wire connected to the pulley, and a sensor mechanism connected to this. A mechanism was used to move and scan.

Furthermore, in the case of a linear pulse motor, the linear pulse motor is fixed inside the device, and a sensor mechanism is directly connected to the movable part to perform scanning.

(Problems to be solved by the invention) By the way, in the conventional Hashi 1': Scanner as mentioned above, a pulse motor that requires a large amount of electric power is used as a driving source, and the power is limited. It is not suitable for electric power devices or portable machines, and the motor itself is expensive.

Further, if the scanning movement is performed manually so as not to use electric power for scanning, there is a problem that accurate image reading cannot be performed because the speed of movement is not constant.

Furthermore, none of the conventional hand scanners uses a DC motor that causes speed fluctuations, and there is also no hand scanner that allows scanning to be performed by scanning by a motor or manually.

(Means for solving the problems) The present invention has been made in view of the above-mentioned circumstances,
It is an object of the present invention to provide an image reading device that can simultaneously satisfy the conflicting conditions of power saving, low cost, and accurate image reading, and can selectively perform automatic scanning and manual scanning.

In order to achieve the above object, the present invention, as shown in FIG. 1, reads an original in close contact with the contact portion 3 of the image original reading surface in one dimension to form a reduced image, and furthermore, it forms a reduced image at right angles to this. In an image reading device that obtains image information by moving the reading position in It has an optical system consisting of a lens 6 for forming a reduced image on an image sensor 7, of which the contact section 3 is fixed to the external housing 1, and consists of a light source 4, a mirror 5, a lens 6, and a one-dimensional image sensor 7. The optical system is fixed to the movable housing 2, and is decelerated by a coupling mechanism consisting of a plurality of gears connected to a DC motor 9 that moves the movable housing 2, thereby rotating a pulley 46 that forms part of the information reading mechanism. Let this pulley 4
The present invention provides an image reading device that is connected to a movable casing 2 via a wire 57 wound around the movable casing 2, and reads image information by moving the movable casing 2.

(Function) In the image reading device according to the present invention, movement for reading and scanning is performed manually or by using the DC motor 9, and power saving is achieved because a stepping motor or a near motor, which consumes a large amount of power, is not required for movement. This makes it possible to use a battery-powered portable machine without using a power supply cord. Also, since the DC motor 9 is cheap,
A low-cost device can be provided.

In addition, the same device can be used for both motor-driven and manual scanning, making it convenient for manual scanning when the battery runs out. ). Furthermore, since both scanning by the DC motor 9 and manual scanning have speed fluctuations, they are used in combination with speed detection.

That is, the apparatus of the present invention has a speed detection structure, and a pulse signal is obtained by detecting the feed speed of the reading device, and a pulse signal corresponding to the feed speed is input to the control circuit, and this pulse signal is Synchronization is achieved by capturing image information input from the COD image sensor only when there is.

As a result, pulses corresponding to changes in the feed speed are generated, and image information is also taken in at that speed, making it possible to achieve accurate image reading.

(Example) Preferred embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a side view showing the inside of an image reading apparatus using the present invention. A movable housing 2 is housed inside an external housing 1. A contact section 3 made of transparent glass or plastic is attached to the upper part of the external housing 1, and a document is placed here.

An LED 4, which is a light source that illuminates this surface, is attached inside the movable housing 2, and the light that illuminates the document is reflected by a lens 1115 that is also attached to the movable housing 2, and a lens 6
The one-dimensional image sensor (COD) of the light receiving element is
The image is focused on element 7.

When the movable housing is moved in the direction of the arrow from the position shown in FIG. moves to the right in the figure. Due to this movement, images of the line sensor are captured one after another to obtain a planar image.

The optical system from the light source to the one-dimensional image sensor is kept relatively stationary. Move the movable housing 2 using the handle 8
A manual pull type or a drive type using a DC motor 9 is used.

In this embodiment, the mirror holder 11 is rotated about the fulcrum shaft 10 so that the angle of the arm can be adjusted so that the light reflected by the mirror 5 enters the center of the lens 6. That is,
Two screws 12a.

12b and rotates the mirror holder 11 to adjust the vertical direction.

FIG. 2 shows a plan view of an image reading device using the present invention. Both ends of the inner movable casing 2 are fixed to the portion 1a of the outer casing 1 so as to slide along shafts 13 on both sides.

2a is a bearing of the movable housing 2.

Next, the motor drive for moving the movable housing 2 will be explained.

The motor required for driving is a C motor 9, which is inexpensive. Note that this motor may have an unstable rotational speed, and does not need to use a governor to keep the rotational speed constant; it may be an inexpensive C motor that simply rotates.

When reading a size document, the movement of the movable housing 2 in the sub-scanning direction is 148.511.

In order to move this moving length in 3 seconds, the rotation speed of the motor 9 is 150 Orpm, and if the pulley diameter for pulling the movable housing 2 is φ10neIm, a coupling mechanism is required to reduce the rotation speed, and this connection The mechanism uses the gear connection shown in FIG.

That is, the first gear 1 is connected to the shaft 9a of the DC motor 9.
4 (binion, which is a small gear) is press-fitted. A second gear 15 (larger gear) is engaged with this gear 14 and rotates around a rotating shaft 16. The rotating shaft 16 is press-fitted into a bushing 17, and the bushing 17 is attached to the gear base plate 1.
8 and is fixed to the external housing 1 by screws 19. A third gear 20 (binion) is integrated with the gear 15 and rotates around the rotating shaft 16. The gear 20 meshes with a fourth gear 21 (thick gear) and rotates around a rotating shaft 22. The rotating shaft 22 is a bushing 2
3, and the bushing 23 is caulked to the gear base plate 18. A fifth gear (binion) is integrated with the gear 21 and rotates around the rotating shaft 22.

A sixth gear 25 (idler gear) meshes with the gear 24. The gear 25 rotates around a shaft 69 that is press-fitted into a bushing (not shown) that is caulked to the lever plate 26. The lever plate 26 rotates around a fulcrum shaft 27. The tensile force of the soup ring 28 causes the gear 25 to mesh with the gear 21 and the seventh gear 29. An operating knob 30 is attached to the lever plate 26. When the operating knob 30 is pushed in the direction of the arrow against the spring 28, the lever plate 26 rotates counterclockwise about the fulcrum shaft 27, and the gear 25 is disengaged from the gears 21 and 29. When you release your hand pressing the operating knob 30, the force of the spring 28 causes the gear 25 to shift to the gear 21 again.
and meshes with gear 29.

In other words, the gears are always in mesh. gear 29
rotates around the rotation axis 31. A pulley 32 rotates around a rotating shaft 31 together with the gear 29. The rotating shaft 31 is press-fitted into a bushing 33 shown in FIG. 3, and the bushing 33 is caulked to a bracket 34. The bracket 34 is fixed to the external housing by screws 35. D.C.
When the first gear 14 attached to the motor 9 rotates at 150 rpm, the speed is reduced and the seventh gear 29 and pulley 32 rotate at 9
It rotates at 4.5 rpl.

FIG. 3 is a schematic side view showing the inside as seen from the opposite side of FIG. 1, and is a diagram showing a mechanism in which the movable housing 2 moves by rotation of the pulley 32. In this embodiment, a hole 32a is provided at the center in the height direction of the pulley 32 that constitutes a part of the information reading mechanism.
A drive wire (thread) is passed through this hole and tied up. The moving length is 148.5 (Actually, it moves a little more than that to allow for margin.) IIIR
Since I, it is sufficient that the pulley diameter φ10mn+ rotates approximately 5 times. Therefore, space is provided above and below the central hole 32a for winding the wire five times. 3, the movable casing 2 is in a position housed within the external casing 1, and the first wire 36 is wound an extra five times below the central hole 32. One end of the wire 36 is tied to a spring 37, and the spring 37 is fixed to a holder base 38 (the 41 holder 11 is also fixed to this) fixed to the movable housing 2. A second wire 39 is wound above the central hole 32a (it is slightly wound at this position), goes around a pulley 40, and is tied to a spring 41, which is fixed to the holder base 38.

Spring 37.41 tensions wire 36.39. The pulley 40 is passed through a rotating shaft 42, the rotating shaft 42 is press-fitted into a bushing 43, and the bushing 43 is caulked to a bracket 44. The bracket 44 is fixed to the external housing 1 with screws 45.

When the movable housing 2 moves out, the first wire 36 unravels, and the pulley 32 rotates in a direction in which the second wire 39 winds around the pulley 32 (rotating clockwise when viewed from above). When the movable housing 2 is pulled out the most, the pulley 3
The wire is wound on the upper side of 2. As long as the wires 36 and 39 are tied and fixed at the center hole 32, a single wire may be used.

Next, the structure of a moving position detection device for performing a reading operation in synchronization with movement speed fluctuations will be explained with reference to FIGS. 1 to 4. FIG. 4 is a cross-sectional side view showing the main structure in the vicinity of the MR sensor. Pulley 46 as shown in FIG.
A magnetic drum 47 having multiple poles on its outer periphery is press-fitted into the housing, and rotates integrally around a rotating shaft 48. The rotating shaft 48 is caulked and fixed to a bracket 50 via a bushing 49. A bracket 52 holding an MR element (magnetoresistive element) 51 is fixed to the bracket 5o by a screw 53. The bracket 50 is fixed by a screw 54 to a holder base 38 that holds the mirror holder 11 and the LED 4. A spring 55 is attached to the inner lower part of the external housing 1 by connecting one end to the bracket 44 and the other end to the spring 55.
The wire 5 fixed by hanging it on the bracket 56
7 (a radio tuning thread may be used), and this wire 57 is wound once around the pulley 46.

The tension of the wire 57 is obtained by a spring 55. When the movable housing 2 moves, the pulley 46 also moves with it, so the pulley 46 wound around the fixed wire 57 rotates. When the pulley 46 rotates, the magnet drum 47 that rotates as a unit also rotates, and if the MR element 51 is placed close to the outer periphery of the magnet drum 47, an output due to magnetic resistance can be obtained. If the outer circumferential line pitch of the magnet poles driven into the outer circumference of the MR element 51 is set at exactly equal intervals (the pitch actually used is 200 μl ± 3%), an output pulse signal proportional to the movement of the movable housing 2 can be generated. You will get it. If the original is read with a resolution of 8 dots/■, one pulse signal will be obtained every 0.125+gm of movement distance, so the outer diameter of the magnetic drum 47 should be set to 16I.
llI111 magnet pole pitch 0.21, pulley 4
If the outer diameter of 6 is 10u, it is 0.125mm movable body 2
An output signal of one pulse is obtained each time the is moved.

FIG. 5 shows a specific example of the circuit of the MR element 51 and a pulse shaping circuit i for amplifying its output to obtain pulses.

Next, manual scanning will be explained. When the knob 30 of the lever plate 26 shown in FIG. 2 is pushed in the direction of the arrow, the gear 29 is separated from the drive connection from the DC motor 9. At this time, when the handle 8 is pulled, the movable housing 2 moves and the image is read by manual scanning. The output pulses from the MR element 51 are also the same as when driving the motor. That is, reading is performed by pulling the handle 8 while pushing the knob 30. At this time, wires 36 and 39 connected via springs 37 and 41 to the holder base 38, which moves integrally with the movable housing 2, move to rotate the pulley 32.

Next, another embodiment will be explained with reference to FIGS. 6 and 7. As shown in FIG. 6, in this embodiment, a magnet drum 58 of the MR sensor portion is attached to the gear 29 and pulley 32 so as to rotate together, and has a similar function. As a result, the magnetic drum 58 rotates when the movable housing 2 moves due to the rotation of the pulley 32 when the motor is driven, so that the pulse output necessary for reading synchronization can be obtained. In this way, the magnet drum 58 is rotated by the force from the DC motor 9 or by the force from the movement of the movable casing 2 during manual operation, but in both cases it rotates with the movement of the movable casing 2. 2 movement will be detected.

Figure 7 shows the position where the movable housing 2 is at its outermost position.
A wire 39 is wound slightly five times above the center hole 32a of the pulley 32. Since the bracket 59 is higher and the rotating shaft 60 is longer, one end 60a of the rotating shaft fits into the hole in the external housing 1, eliminating the cantilever and preventing it from tilting due to the tension of the wires 36 and 39. There is.

Next, an outline of the configuration of this device including signal processing and control circuits will be explained with reference to FIG. CCD line sensor 7
The output signal of 61 is an amplifier 62 and an automatic gain control circuit (AGC) 6 in order to make it an advantageous signal for converting into binary data.
3, it is binarized and output.

An output pulse obtained by moving the movable housing 2 is input to the control circuit 64 . The circuit portion is located in the inner part of the external housing 1 (near the DC motor 9) and in a portion that does not obstruct the optical path within the movable housing 2, but is not shown.

FIG. 9 shows the control timing factor. First, as shown in FIG. 9(A), the CCD line sensor always receives a reading timing pulse P 1 of a constant required period and a required control signal (not shown) from the control circuit 64. A read signal is output, binary data is obtained as described above, and is written to the 1-line buffer memory 65 for each line at the timing shown in FIG. 9(B). FIG. 9 (C) from MR sensor 51
A data output permission signal P3 as shown in FIG. 9(D) is applied from the control circuit 64 to the latch circuit 66 by the output pulse P2 as shown in FIG. 9(D), thereby obtaining a desired output signal. That is, since an output signal is obtained only when there is an output pulse from the MR sensor 51, synchronization can be achieved with the movement timing by manual or DC motor drive.

In this embodiment, the image sensor device is a reduction optical system using lens 6, but the present invention is applicable even to an image scanner device having a contact type image sensor having a line sensor with the same width as the document. It is valid.

Note that transparent glass or plastic is attached to 67, and when the movable housing 2 is pulled out, it can be seen by tilting it up and down, allowing you to position the document from above when the document surface is facing down. I'm making it easy.

Further, 68 is a battery case with a built-in battery structure, making it suitable for a handy scanner.

(Effects of the Invention) According to the present invention, scanning for image reading is performed manually or driven by a DC motor, and a scanning method with low power consumption is obtained. Having a built-in battery eliminates the need for a DC supply wire, making it an easy-to-use handy scanner. It is battery-powered and can be used manually, so if you don't have a battery or the battery runs out, you can scan manually.

Since the gears are always in mesh, the movable housing does not slip out and come out, making the device more stable than systems that only use manual scanning.

In terms of cost, manual operation and inexpensive C motors are advantageous.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the inside of an embodiment of the image reading device according to the present invention, FIG. 2 is a plan view of the image reading device, and FIG. 3 is a side view seen from the opposite side of FIG. 1. FIG. 4 is a cross-sectional side view showing the main structure of the MR sensor; FIG. 5 is an example of a circuit that obtains pulses from the output from the MR element; FIG. 7 is a side view showing the main parts of another embodiment, FIG. 7 is a diagram when the movable housing is moved from the state shown in FIG. 6, and FIG. 8 is a configuration of the device of the present invention including signal processing and control circuits. FIG. 9 is a control timing diagram showing the operating state of the embodiment according to the present invention. DESCRIPTION OF SYMBOLS 1... External housing, 2... Movable housing, 3... Contact part, 4... Light source (LED), 5... Mirror, 6...
・Lens, 7...1-dimensional image sensor, 9...D
C motor, 14.20.21.24.25.29...
Gear, 26...Lever plate, 32.46...Pulley,
36°39.57... wire, 51... magnetoresistive element. Figure 4 Figure 5 Figure 8 Figure 9

Claims (3)

[Claims] (1) Image In an image reading device that obtains image information by reading an original in close contact with a contact portion of an image original reading surface in one dimension, forming a reduced image, and then moving the reading position in a direction perpendicular to this, It has an optical system consisting of a light source for irradiation, the contact section, a mirror that guides the image information light to a lens, a one-dimensional image sensor, and a lens that reduces and forms an image on the one-dimensional image sensor. The optical system, which is fixed to the body and consists of a light source, a mirror, a lens, and a one-dimensional image sensor, is fixed to a movable housing, and a DC motor that moves this movable housing
A connection mechanism consisting of a plurality of gears connected to the motor rotates a pulley that forms part of the information reading mechanism by decelerating the motor, and is connected to a movable casing via a wire wound around this pulley. An image reading device that reads image information by moving your body. (2) Attach one of the gears connected to the DC motor to a lever plate that rotates around the fulcrum shaft, disconnect the drive from the DC motor by rotating the lever plate, and manually move the movable housing. The image reading device according to claim 1, further comprising a connecting mechanism that allows the image reading device to perform the following steps. (3) One pulley is rotated by the movement of the movable housing.
By arranging a magnetic drum having a plurality of magnetic poles around its periphery and arranging a magnetoresistive element near the outer periphery of the magnetic drum, an information reading mechanism is provided that generates a pulse output as the movable casing moves. . The image reading device according to claim 1, wherein image information is captured only when the pulse output is output.