JP4780660B2 - LIGHTING DEVICE AND IMAGE READING DEVICE HAVING THE SAME - Google Patents

Description

  The present invention relates to an illumination device that configures a light source by aligning a plurality of light source elements in a line, and an image reading device including the illumination device.

  2. Description of the Related Art In an image reading apparatus used for an image forming apparatus such as a copying machine or a printer, an illumination device having a line-shaped light source is known. In this case, the original is irradiated with the light source while the original is moved relative to a line-shaped light source along the reading width in a direction orthogonal to the line. Reflected light from the original is received by an imaging element such as a CCD through an imaging lens, whereby the image surface of the original is read. In such an illuminating device, conventionally, a rod-like fluorescent lamp or a xenon lamp has been used as a light source.

  In the above-described fluorescent lamp and xenon lamp, the phosphor is applied to the entire inner surface of the fluorescent tube in the former case, and the ultraviolet reflecting film coated on the entire inner surface of the outer tube in the latter case emits light in a planar shape. Therefore, there is an advantage that uneven irradiation hardly occurs. On the other hand, these light sources have drawbacks such as high power consumption, large amount of heat generation, and short life.

  As a light source for solving this disadvantage, a light source unit is proposed in which a plurality of light source elements (for example, LED elements) as point light sources are arranged in a line shape (see, for example, Patent Document 1). LED elements generally have advantages such as low power consumption, low calorific value, and long life.

JP 2002-320074 A

  Here, when the light source disclosed in Patent Document 1 fails to light even one of a plurality of light source elements due to damage or the like, the light source is printed on a sheet by a copying machine or a printer based on the read image information. When a toner image is formed on the surface, black streaks are generated at locations corresponding to the light source elements. For this reason, it is necessary to replace the light source element that is no longer lit.

  However, the thing of patent document 1 constitutes one light source unit by integrally assembling a plurality of light source elements and substrates arranged in a line. Therefore, it is not possible to replace only one light source element that is not lit, and it is necessary to replace the entire light source unit, which is disadvantageous in terms of cost and resource saving.

  An object of the present invention is to divide a plurality of light source elements into light source units having one or two or more light source elements and the same number of light guide lenses in a lighting device having a plurality of light source elements aligned in a line. An object of the present invention is to provide an illuminating device capable of improving economy and contributing to resource saving by enabling replacement for each unit, and an image reading apparatus provided with the illuminating device.

According to a first aspect of the present invention, there is provided a light source that irradiates an image surface of a document in a line shape, and a moving device that relatively moves the light source and the document so that the document moves in a direction perpendicular to the line. The present invention relates to a lighting device including
In the lighting device according to the present invention,
(1). The light source is
a. It is configured by aligning multiple light source elements in a line,
b. And integrally hold the single light source element and a single light guide lens in a single first housing, a first type which emits light from the light source device via the light guide lens a light source Uni Tsu city of,
Two or more of the light source elements and these light source elements and the same number of the light guide lens holding integrally the second housings in a ring of a single, to emit light from the light source device via the light guide lens A second type of light source unit adapted to,
Is composed of multiple combinations,
c. The first type of the light source element and the second type of the main board to the circuit for supplying electric power to the light source element is formed of a light source unit of the light source unit, wherein the first type of light source unit and the second type The light source units are individually detachably attached.
(2). An electrode is formed on a surface of the main board on which the first and second light source units are attached, and a holder for detachably positioning the first and second light source units for each of the first and second light source units. Is formed.
(3). The holder is formed for each of the first type and second type light source units, and includes a plurality of elastically deformable hooks formed so as to face each other.
(4). Each of the plurality of hooks is formed with a claw portion that protrudes so as to narrow the distance from the other hook facing the tip.
(5). When the first type and the second type light source unit are pushed between the hooks facing each other beyond the hooks of the hook and pressed onto the main board, the first type and the second type The electrode mounting surface of the light source unit is in contact with the electrode on the main board, and the light source element and the circuit on the main board are electrically connected, and are held on the main board by the elastic force of the hook. It has become.

  According to a second aspect of the present invention, in the illumination device according to the first aspect, the light sources are aligned at a predetermined pitch that allows the plurality of light source elements to irradiate the image surface of the original document evenly along the line direction. It is characterized by that.

The invention according to claim 3 is characterized by the light source of the illumination device according to claim 1 or 2 . That is, the light source is configured by the number of the light source elements corresponding to the irradiation width of the original with the smallest irradiation width in the line direction among the originals to be irradiated and the same number of the light guide lenses. It has the said 1st type or 2nd type light source unit, It is characterized by the above-mentioned.

The invention according to claim 4 is characterized in that the light source of the illumination device according to claim 1 or 2 is characterized. That is, the light source, of said original plurality of kinds of different irradiation width as the irradiation target, wherein corresponding to the difference of the irradiation width the number of the light source elements and the same number of the light guide lens first type constituted by Or it has the 2nd type light source unit.

The invention according to claim 5 is characterized in that, in the illumination device according to any one of claims 1 to 4 , the light source element is an LED element.

According to a sixth aspect of the present invention, there is provided an illuminating device that irradiates an image surface of the document while relatively moving a light source and the document, and an image by reflected light that is emitted from the illuminating device and reflected by the image surface of the document. The present invention relates to an image reading apparatus including an imaging lens that forms an image and a solid-state imaging device. The image reading apparatus according to the present invention is characterized in that the illumination device is the illumination device according to any one of claims 1 to 5 .

According to the first aspect of the present invention, the image surface of the document is irradiated in a line shape by the light source, and further, the light source and the document are relatively moved by the moving device in the direction in which the line and the moving direction of the document are orthogonal, The entire image surface of the document can be illuminated by the light source. In this case, for example, if one of the light source elements stops lighting due to life, failure, breakage, etc., or the illuminance is extremely reduced, the light source is not replaced, but the light source is switched on. Since it is sufficient to individually replace the light source unit including the light source element and the light guide lens that are no longer used, it is economical and resource saving can be achieved. Further, for example, when the light source is stocked as a service part, it is possible to save the storage space. Furthermore, since the light emitted from the light source element can be condensed by the light guide lens, it is possible to use a light source element with a small amount of light emission. In the invention according to the present invention, one light source unit and one light guide lens constitute one light source unit, and a plurality of light source elements and the same number of light guide lenses are used. This includes both the case where a single light source unit is configured. In the latter case, when the light source element stops lighting, there is an advantage that it is extremely economical because the light source unit including the light source element may be replaced. When the light source unit is composed of two or more light source elements and the same number of light guide lenses, one light source element and one light guide lens constitute one light source unit. Compared with this, the economy and assemblability are improved. Here, in the case of “two or more light source elements and the same number of light guide lenses”, “the same number” means that a portion that substantially acts as a light guide lens is 1 for one light source element. This means that there is a plurality corresponding to one-to-one. Thus, one light guide lens to a plurality have a portion which acts as a substantially light guide lens are also included in the present invention.

  According to the second aspect of the present invention, a plurality of light source elements, which are point light sources, are arranged in a line at a predetermined pitch, so that the image surface of the original can be irradiated evenly.

Claims 3 and 4 show an example in which the light source unit is configured based on the irradiation width of the document. That is, it provides a basis for unitizing the light source elements. According to the third aspect , since the light source unit is configured by the number of light source elements corresponding to the irradiation width and the same number of light guide lenses of the document having the minimum irradiation width, the light source elements in the light source unit are turned on. If this is not the case, the entire light source unit will be replaced. According to claim 4 , since the light source unit is configured by the number of light source elements corresponding to the difference in irradiation width and the same number of light guide lenses, when the light source elements in the light source unit stop lighting. The light source unit will be replaced. Thus, according to claims 3 and 4 , the light source can be effectively unitized.

According to the invention of claim 5 , since the light source element is an LED element, there are advantages such as low power consumption, low calorific value, and long life.

According to the sixth aspect of the present invention, the illumination device, which is a main component of the image reading apparatus, can provide the above-described effects, and thus the entire image reading apparatus can also exhibit the effects.

  Hereinafter, the best embodiment of the present invention will be described in detail with reference to the drawings. In the following drawings, illustrations of members unnecessary for explanation are omitted as appropriate.

<Embodiment 1>
With reference to FIGS. 1-4, the illuminating device 10 which concerns on this invention, and the image reading apparatus 11 provided with the same are demonstrated. In the present embodiment, a case where one light source unit is configured by one LED element (light source element) and one light guide lens will be described as an example.

  1 and FIG. 2 are views of the longitudinal section of the image reading device 11 as seen from the front side (front side). Further, FIG. 1 shows an optical system, and FIG. 2 shows a drive system. FIG. 3 and 4 are top views for explaining the relationship between the light source 12, the size of the document, and the position of the document at the time of image reading. Further, FIG. 3 shows the case where the document size is A row and B row, FIG. 4 shows a case where the document size is an inch size. In the following description, the left and right in FIGS. 1 to 4 are the left and right of the image reading device 11, the top and the bottom in FIGS. 1 and 2 are the top and bottom of the image reading device 11, and FIGS. The lower and upper parts in the middle will be described as before and after the image reading apparatus 11, respectively. Further, the length in the vertical direction of the document in FIGS. 3 and 4 is referred to as the sheet passing width (or simply “width”), and the length in the left and right direction is referred to as the conveyance direction length (or simply “length”).

  As shown in FIG. 2, the image reading device 11 includes an illumination device 10, an imaging lens 13, and a CCD (solid-state imaging device) 14. Furthermore, the illumination device 10 includes a light source 12 and a driving device (moving device) 15. The light source 12, the driving device 15, the illumination device 10, the imaging lens 13, and the CCD 14 are all disposed inside a rectangular parallelepiped housing (frame) 16. The housing 16 has an opening 17 on its upper surface, and a transparent contact glass 18 is disposed in the opening 17.

  As shown in FIGS. 3 and 4, the contact glass 18 is formed in a rectangular shape larger than the document of the maximum size among the sheet-like documents placed on the upper surface thereof. In the contact glass 18, a left indicator plate 20 that is long in the front-rear direction is provided at the left end, and a rear indicator plate 21 and a front indicator plate 22 that are long in the left-right direction are provided at the rear end and the front end, respectively. A position where the rear end of the left indicating plate 20 and the left end of the rear indicating plate 21 intersect is a reading reference position P0. The document placed on the contact glass 18 is positioned at one corner (namely, the left corner and the rear corner) (reference corner) at a position (predetermined position) aligned with the reading reference position P0. Placed. 3 and 4, originals of various sizes in a state where the reference corner is set to the reading reference position P0 are illustrated. Here, the size and orientation of each original are displayed at positions corresponding to the diagonals of the reference corners in the originals of each size. For example, B5 and A4 in FIG. 3 indicate the position of the original when the “long side” of each original is aligned with the left indicating plate 20. Hereinafter, this is referred to as “horizontal placement” of the manuscript. B5R and A4R indicate the position of the original when the “short side” of each original is aligned with the left indicating plate 20. Hereinafter, the “R” attached is referred to as “vertical placement” of the document and is distinguished from “horizontal placement”. According to this, “B4” and “A3” in FIG. 3 should be originally described as “B4R” and “A3R”, but originals of these sizes can be placed horizontally. In other words, only one way of placement is possible and there is no need to distinguish between them.

  The notations such as “B5”, “B5R”, “A4”, “A4R”, “B4”, “A3”, etc. are not actually shown on the contact glass 18 but on the left indicator plate 20 and the rear indicator plate 21. Has been. For example, the positions indicated by reference signs P1, P2, P3, and P4 on the left indicating plate 20 are represented as “B5R”, “A4R”, “B5, B4”, and “A4, A3” in this order. On the other hand, the positions indicated by reference signs P5, P6, P7, and P8 on the rear indicating plate 21 are labeled “B6R, B5”, “A5R, A4”, “B5R”, and “A4R” in this order. Thus, the user can know the document size and orientation when the document is placed at a predetermined position on the contact glass 18. Therefore, for example, when an image is formed on a sheet of paper or the like by a copying machine or a printer based on the image reading result of the document, it is a reference when selecting the size and orientation of the sheet used for image formation. It can be. In FIG. 4, the document size is displayed in inches. In the contact glass 18 in FIG. 3, the width that is slightly larger than the sheet passing width of “A4, A3” is the maximum image reading width (maximum irradiation width), and “11 × 17” in the contact glass 18 in FIG. 4. The range slightly longer than the conveyance length of “” is the maximum image reading length (maximum irradiation length). The light source 12, which will be described later, can irradiate the entire maximum reading area surrounded by the maximum reading width and the maximum reading length.

  As shown in FIGS. 1 to 4, an illumination optical movement frame unit 23 is disposed below the left end side of the contact glass 18. The illumination optical movement frame unit 23 has a movement frame 24 having a length in the front-rear direction longer than the above-described maximum reading width. On the moving frame 24, a light source main substrate (substrate) 25 to which the light source 12 is attached, a concave mirror 26, and a first mirror 27 are mounted. 3 and 4, the light source main board 25 is formed such that the length in the front-rear direction is longer than the maximum reading width, and the upper surface thereof is provided with a housing to be described later. The light source 12 and the light guide lens 19 are attached. In the present embodiment, the light source 12 is configured by arranging a plurality (22 in FIG. 3 and FIG. 4) of LED elements L1 to L22, which are point light sources, in a line shape in the front-rear direction. Here, the line shape is not limited to a case where the lines are aligned on a single straight line, but includes, for example, a case where the lines are aligned in a staggered pattern and are substantially linear. These LED elements L1 to L22 are aligned at a predetermined pitch P (15 mm in the present embodiment) that can irradiate the image surface of the original document evenly along the line direction (front-rear direction). 3 and 4, the distance from the center of the rearmost LED element L1 to the center of the frontmost LED element L22 is set to 315 mm (= 15 mm × 21). These LED element L1 and LED element In the example shown in FIG. 3, the long side (= 297 mm) of the A4 size original having the maximum sheet passing width or the short side (= 297 mm) of the A3 size original is inserted between L22 and FIG. In the example shown in FIG. 5, the long side or the short side is set so that the long side or the short side of the document having an 11-inch (≈279 mm) length is included. As shown in FIG. 1, the light source 12 composed of a plurality of LED elements L <b> 1 to L <b> 22 irradiates the reading line L set on the upper surface of the contact glass 18 from the lower right side. The LED elements L1 to L22 and the light source main board 25 will be described in detail later.

As shown in FIG. 1, the concave mirror 26 is disposed at a position that is substantially line-symmetric with the light source 12 described above with respect to a perpendicular line that is lowered from the reading line L. As described above, since the light source 12 irradiates the document on the contact glass 18 obliquely from the lower right, a shadow is formed at the left end of the document, and this shadow tends to be read as an image on a straight line in the front-rear direction. It is. The concave mirror 26 reflects light from the light source 12 and guides it to the reading line L to remove the shadow. A first mirror 27 is disposed in a portion of the illumination optical movement frame unit 23 located immediately below the reading line L. The first mirror 27 is attached in a state in which 45 degrees on the upper left is turned. As described above, the illumination optical moving frame unit 23 has a guide member (not shown) laid in the left-right direction with the light source 12, the light source main board 25, the concave mirror 26, and the first mirror 27 mounted on the moving frame 24. ) Along the horizontal direction. That is, the illumination optical movement frame unit 23 can move in a direction orthogonal to the linear (linear) light source 12. The illumination optical moving frame unit 23 emits light from the light source 12 toward the reading line L while moving rightward, and guides reflected light from the image surface of the document to a second mirror 28 described below. It is.

  As shown in FIGS. 1 and 2, below the left end side of the contact glass 18, a reflection optical moving frame unit 30 is disposed on the left side of the above-described illumination optical moving frame unit 23. The reflective optical moving frame unit 30 has a moving frame 31 that is longer in the front-rear direction than the above-described maximum reading width. A second mirror 28 is mounted on the moving frame 31 in a state where the lower right angle is 45 degrees, and a third mirror 32 is mounted in an attitude where the upper right angle is 45 degrees. Further, the moving frame 31 rotatably supports the movable pulley 33 at its front end and rear end. As described above, the reflection optical moving frame unit 30 is mounted in the left-right direction along the guide member (not shown) laid in the left-right direction with the second mirror 28, the third mirror 32, and the movable pulley 33 mounted thereon. Can be moved to. The optical movement frame unit 30 for reflection reflects light from the first mirror 27 of the optical movement frame unit 23 for illumination described above by the second mirror 28 and the third mirror 32 while moving to the right. It leads to the imaging lens 13.

  As shown in FIG. 2, fixed left pulleys 34 and 34 are provided at the front and rear ends in the vicinity of the left end of the housing 16, and fixed right pulleys 35 and 35 are provided at the front and rear ends in the vicinity of the right end of the housing 16. Are rotatably arranged. Further, a motor 36 capable of forward and reverse rotation is disposed below the fixed right pulleys 35 and 35 in FIG. Further, a drive pulley 38 that is integral with the drive shaft 37 is disposed on the left side of the motor 36, and a drive belt 41 is stretched between the output shaft 40 of the motor 36 and the drive pulley 38. Yes. Wire drums 42 and 42 are fixed to the front end and the rear end of the drive shaft 37, and optical wires 43 and 43 are wound around the wire drums 42 and 42, respectively. One end portions 44 of the optical wires 43 are fixed to the inner surface of the left side wall 45 of the housing 16. The optical wires 43, 43 extend rightward from here, hang around the right half of the movable pulleys 33, 33 of the reflecting optical moving frame unit 30, are folded back leftward, and left of the fixed left pulleys 34, 34. After being stretched over the half, it is folded rightward and extends toward the fixed right pulleys 35 and 35. Further, it is stretched to the left half of the fixed right pulleys 35 and 35 and extends to the left. After being fixed to the illumination optical movement frame unit 23 in the middle, it further extends to the left and the movable pulleys 33 and 33 It is stretched over the left half, folded back to the right, and locked to a hook 47 protruding on the lens mount 46. When the motor 36 rotates counterclockwise in FIG. 2 based on the routing of the optical wires 43, 43, the wire drums 42, 42 are also anti-clockwise via the drive belt 41, the drive pulley 38, and the drive shaft 37. Rotate clockwise. Along with this, the illumination optical movement frame unit 23 and the reflection optical movement frame unit 30 move to the right by being pulled by the optical wires 43 and 43. At this time, since the movable pulleys 33 and 33 of the reflecting optical moving frame unit 30 act as a so-called moving pulley, the moving distance becomes half of the moving distance of the illumination optical moving frame unit 23. Accordingly, the optical path length from the contact glass 18 to the imaging lens 13 is kept constant regardless of the movement of the illumination optical moving frame unit 23 and the reflecting optical moving frame unit 30, and the imaging lens described below The light passing through 13 forms an image on the CCD 14. In the present embodiment, the entire configuration for moving the light source 12 as described above corresponds to a driving device (moving device).

As shown in FIG. 2, the imaging lens 13 is fixed on a lens mounting plate 48 fixed to the lens mounting base 46 described above. The light emitted from the light source 12 is reflected by the image surface of the document and follows the optical path K shown in the figure (see FIG. 1) . That is, the reflected light from the image surface is reflected by the first mirror 27, the second mirror 28, and the third mirror 32 and is incident on the imaging lens 13. The incident light is imaged on the CCD 14 described next.

  The CCD 14 is attached to a “U” -shaped CCD adjustment plate 52 that is fixed to the above-described lens mounting base 46 via a CCD mounting plate 51 that is fixed to the left end surface and the upper end portion 50 is bent to the left. ing. Bosses 53 and 53 having internal threads threaded on the inner diameter are fixed to the front end portion and the rear end portion of the CCD adjustment plate 52, and the upper end portion 50 of the CCD mounting plate 51 is attached to these bosses 53 and 53. The penetrated pins 54 and 54 are screwed together. Further, compression springs 55 and 55 are interposed between the CCD mounting plate 51 and the CCD adjustment plate 52 to urge the CCD mounting plate 51 upward. In this state, the height position of the CCD 14 can be finely adjusted via the CCD mounting plate 51 by turning the pins 54 and 54 clockwise or counterclockwise. By performing this fine adjustment at the front end and the rear end of the CCD 14, the vertical position adjustment of the CCD 14 can be performed.

  As described above, the image surface of the original is irradiated along the reading line L by the light source 12 of the optical system (main scanning), and further, the reading line L is moved to the right by the driving system to perform scanning (sub scanning). As a result, the image surface of the document can be sequentially read by the CCD 14 over the entire area.

With reference to FIGS. 5A, 5B, and 5C, a structure for attaching / detaching the light source unit U1 to / from the light source main board 25 and the attaching / detaching operation thereof will be described. Here, the light source unit U1 is the light source unit U1 including the LED element L1 located at the rearmost end shown in FIGS. FIG. 5A is an enlarged view of the vicinity of the light source unit U1 as seen from above. FIG.5 (b) is a figure cut and shown along the AA line of Fig.5 (a). FIG.5 (c) is a figure cut and shown along the BB line of Fig.5 (a). In this embodiment, as shown in FIGS. 3 and 4, the light source 12 is configured by aligning a plurality (22) of LED elements L <b> 1 to L <b> 22 in a line shape. The light source 12 is divided into a plurality of (22 in the present embodiment) light source units configured by integrally holding one LED element and one light guide lens by one housing. Each divided light source unit can be individually replaced. Hereinafter, a case where the light source unit U1 configured by the LED element L1 and the light guide lens M1 positioned at the rearmost end and the housing H1 that integrally holds the LED element L1 is attached to and detached from the light source main board 25 will be described as an example. To do.

  The LED element L1 shown in FIGS. 5A and 5C is configured in a square plate shape with a side length of, for example, 3.5 mm, and the irradiation angle has a spread of about 120 degrees. . The light guide lens M1 is constituted by two circular surfaces and an outwardly convex side surface between them. An aspherical lens or a Fresnel lens can be used as the light guide lens M1, but in the present embodiment, the former aspherical lens is used. When the temperature of the light guide lens M1 is high during use, the desired performance cannot be obtained. Therefore, in such a case, for example, a cooling fan (not shown) is provided to prevent the temperature of the light guide lens M1 from rising. The LED element L1 and the light guide lens M1 described above are integrally held by the housing H1.

  The housing H1 is formed in a substantially cylindrical shape. As shown in FIGS. 5 (b) and 5 (c), an annular groove 61 is formed in the vicinity of the lower end (the upper end in FIG. 5 (b)) of the outer peripheral surface of the housing H1 over the entire outer periphery. A flange portion 60 is formed between the annular groove 61 and the lower end. The flange portion 60 is a portion with which hooks 71 to 74 described later on the light source main board 25 side are engaged. As shown in FIG. 5B, an LED mounting portion 62 having the same shape as the LED element L1 is formed on the lower end side (the upper side in the figure) of the inner peripheral surface of the housing H1, and the LED element L1 is formed here. Is stored. Further, a cylindrical lens mounting portion 63 is formed on the upper end side (lower side in the figure) of the inner peripheral surface of the housing H1, and the light guide lens M1 is housed therein. A frustoconical space 64 is formed in a portion corresponding to the space between the LED element L1 and the light guide lens M1 in the housing H1. The light emitted from the LED element L1 passes through the space 64 and reaches the light guide lens M1. Thus, in this embodiment, the LED element L1 and the light guide lens M1 are positioned by the single housing H1, and the distance between them can be accurately maintained. Therefore, as compared with the case where the LED element L1 and the light guide lens M1 are configured separately, the illuminance on the document image surface by the light emitted from the LED element L1 and collected by the light guide lens M1. Can be made constant. Therefore, as will be described later, when the same configuration is used for a plurality of light source units, it is possible to reduce the illuminance unevenness of each light source unit.

  As shown in FIG. 5 (a), an annular retaining 65 is fitted to the lower end of the housing H1 to prevent the LED element L1 from falling off. An electrode (not shown) is provided on the lower surface of the retainer 65 and serves as an electrode installation surface. On the other hand, an annular retainer 66 is fitted to the upper end of the housing H1 to prevent the light guide lens M1 from falling off.

  As described above, in the present embodiment, one LED element L1 and one light guide lens M1 are integrally formed by one housing H1 to form one light source unit U1. The same applies to the LED elements L2 to L22 other than the above-described LED element L1 among the LED elements L1 to L22 shown in FIGS. That is, the LED elements L2 to L22 are the LED element L1, the light guide lenses M2 to M22 (not shown) are the light guide lens M1, the housings H2 to H22 are the housing H1, and The light source units U2 to U22 (not shown) are formed in the same manner as the light source unit U1 described above. The LED element Ln (where n is an integer satisfying 1 ≦ n ≦ 22) and the light guide lens Mn are integrally held by the housing Hn so as to constitute one light source unit Un. . By aligning the single light source unit Un as a unit in a line shape in the front-rear direction, the entire light source 12 is configured and can be individually replaced in units of the light source unit Un.

  Next, a configuration for attaching / detaching the light source unit U1 to / from the light source main board 25 and an attaching / detaching operation thereof will be described.

As shown in FIG. 5, two pairs of hooks 71 and 72 and hooks 73 and 74 project from the upper surface 70 of the light source main board 25 as holders for mounting the light source unit U1. Of these, the hooks 71 and 72 are at positions corresponding to the center in the front-rear direction of the housing H1 (the direction along the line AA in FIG. 5A) , and the hooks 73 and 74 are the left-right direction of the housing H1. It is disposed at a position corresponding to the center of ( the direction along the line BB in FIG. 5A) . That is, these hooks 71 to 74 position and hold positions corresponding to the centers of the LED element L1 in the front-rear direction and the left-right direction in the housing H1, thereby increasing the positioning accuracy of the LED element L1. . Each of the hooks 71 to 74 is formed in the same shape, and an inclined portion a and a claw portion b are formed inside each of the hooks 71 to 74. As shown in FIG. 5 (b), the intervals between the inclined portions a, a of the hooks 71, 72, and as shown in FIG. 5 (c), the intervals between the inclined portions a, a of the hooks 73, 74. Is set so that the distal end side is wider than the outer diameter of the flange portion 60 on the housing H1 side and the proximal end side is narrower than the outer diameter of the flange portion 60. The height from the light source main board 25 to the claw portions b and b is set to be substantially the same as the thickness of the flange portion 60 on the housing H1 side. The hooks 71 to 74 are elastically deformed when the light source unit U1 is attached to or detached from them. An electrode (not shown) is provided on a surface surrounded by the hooks 71 to 74 on the upper surface 70 of the light source main board 25, and this surface serves as an electrode installation surface. In addition, a circuit (not shown) for supplying power to the LED element L1 is formed on the light source main board 25 through the electrode of the retaining member 65 on the housing H1 side.

When the light source unit U1 is mounted on the light source main board 25, first, as shown in FIG. 5, the light source unit U1 is positioned above the hooks 71 to 74, and the light source unit U1 is pushed into the hooks 71 to 74. When the flange portion 60 on the housing H1 side is related to the inclined portion a of the hooks 71 to 74, the hooks 71 and 72 and the hooks 73 and 74 that are paired with each other are expanded by the flange portion 60 between the inclined portions a and a. It will be elastically deformed. And as for each hook 71-74, if the flange part 60 exceeds the inclination part a, the nail | claw part b will be engaged with the annular groove 61. FIG. Thus, wearing completion of the light source unit U1 to the main board 25 light source, a main substrate 25 side of the electrode installation surface light source at the same time, is in contact with the electrode installation surface of the stopper 65 of the housing H1 side, light source Conduction is achieved between the main board 25 and the LED element L1. The mounting of the light source unit U1 on the light source main board 25 described above is a simple operation of pushing the housing H1 between the hooks 71 to 74 as an actual work, and can be performed in an extremely short time. On the other hand, when removing the light source unit U1 from the light source main board 25, the distance between the hooks 71 and 72 and the distance between the hooks 73 and 74 are easily increased. Can be removed.

  The hooks 71 to 74 for attaching the light source unit U1 located at the rear end have been described above, but the same configuration can be adopted for the other light source units U2 to U22.

  According to the present embodiment, for example, when one of the plurality of LED elements L1 to L22 constituting the light source 12 cannot be turned on due to life, failure, breakage, or the illuminance is extremely reduced. Since it is sufficient to replace the light source unit including the LED element that is no longer lit, instead of replacing the entire light source 12, it is economical and resource saving can be achieved. Furthermore, for example, when the light source 12 is stocked as a service part, it can be stocked as a light source unit, so that the storage space can be saved.

  Further, according to the present embodiment, the light emitted from the LED element is condensed by the light guide lens and then irradiated to the image surface of the document. Therefore, the image surface of the document is irradiated by the light from the LED element. Irradiation can be performed efficiently. Therefore, it is possible to use an LED element itself having a small light emission amount.

<Embodiment 2>
In this embodiment, an example will be described in which a plurality of LED elements and the same number of light guide lenses are held by one housing to constitute one light source unit.

  An example of how to determine the number of LED elements and light guide lenses included in one light source unit will be described with reference to FIG. As shown in the figure, in the present embodiment, when the image surface of a document is irradiated, the following LED elements and light guide lenses are used corresponding to the size of the document.

A6R: LED elements L1 to L9 and light guide lenses M1 to M9
B6R: LED elements L1 to L11 and light guide lenses M1 to M11
A5R: LED elements L1 to L12 and light guide lenses M1 to M12
B5R: LED elements L1 to L14 and light guide lenses M1 to M14
A4R: LED elements L1 to L16 and light guide lenses M1 to M16
B5, B4: LED elements L1 to L19 and light guide lenses M1 to M19
A4, A3: LED elements L1 to L22 and light guide lenses M1 to M22.

  Here, for example, if the minimum irradiation width (minimum reading width) of the document is A6R, the LED elements L1 to L9 and the light guide lenses M1 to M9 described above are used when all the documents are irradiated. Further, in B6R that is one size larger than A6R, in addition to the LED elements L1 to L9 and the light guide lenses M1 to M9, the LED elements L10 and L11 and the light guide lenses M10 and M11 are used.

  Therefore, in the present embodiment, when the light source unit is configured, the number of LED elements and light guide lenses to be unitized is determined based on the difference between the minimum irradiation width and the irradiation width of the document (difference in sheet passing width). I made it. That is, one light source unit is configured by nine LED elements L1 to L9, nine light guide lenses M1 to M9, and one housing corresponding to the minimum irradiation width. Furthermore, it united as follows corresponding to the difference of irradiation width.

Difference between A6R to B6R: unitization of two LED elements L10 and L11 and two light guide lenses M10 and M11 and one housing Difference between B6R to A5R: one LED element L12 and one Unitization of light guide lens M12 and one housing A5R to B5R difference: unitization of two LED elements L13 and L14 and two light guide lenses M13 and M14 and one housing B5R to A4R difference: unitization of two LED elements L15, L16 and two light guide lenses M15, M16 and one housing A4R to B5, B4 difference: three LED elements L17, L18, L19 And unitization of three light guide lenses M17, M18, M19 and one housing Difference between B5, B4 to A4, A3: Three LED elements L20, L2 , L22 and three light guide lens M20, M21, and M22, units of the one housing.

  As described above, in the present embodiment, nine LED elements and nine light guide lenses and one housing are unitized corresponding to the minimum irradiation width, and the difference in irradiation width is supported. Then, one, two, and three LED elements and the same number of light guide lenses and one housing were unitized. In unitization, when the number of LED elements to be unitized is the same, it can be handled as the same light source unit. Therefore, in the above-described example, it is sufficient to prepare one, two, three, and nine LED elements as unitized light source units. Here, one unitization means that a light source unit is formed by one LED element, one light guide lens, and one housing, which is the same as that in the first embodiment. It is equivalent. Further, when one light source unit is constituted by two or more LED elements, the same number of light guide lenses, and one housing, in the first embodiment, the housing is replaced with a substantially cylindrical housing. A rectangular parallelepiped housing having a length corresponding to the number of the LED elements or the like may be used. Even in this case, it is possible to attach the housing to the light source main board using a hook in the same manner as described above.

  In addition, when the size of the document shown in FIG. 4 is an inch size, it can be unitized in the same way as described above.

  According to the present embodiment, since the unitization of the light source 12 is performed based on the irradiation width (reading width) of the document, that is, the difference between the minimum irradiation width and the irradiation width, efficient unitization without waste is performed. can do.

  In the above-described embodiment, an example has been described in which a so-called side reference is used in which the rear end of the original is aligned with the front end of the rear indicator plate 21 when the original is set on the contact glass 18. The present invention is not limited to this, and can also be applied to a configuration employing a so-called center reference in which the center of the sheet passing width of the document is aligned with the center of the contact glass 18 in the front-rear direction.

  In the above embodiment, the case where the original is fixed and the light source 12 is moved when the image surface of the original is irradiated by the light source 12 has been described as an example. However, the present invention replaces this by fixing the light source 12. However, the present invention can be similarly applied to the case of moving the document. The method for moving the document is not particularly limited, and for example, a known transport device that transports the document with a transport roller can be used.

  Each light source unit described above may be provided with an auxiliary substrate (not shown). An auxiliary board is integrally attached to the lower surface of the housing, and the auxiliary board and each LED element are electrically connected, and electrodes are provided on the auxiliary board. Accordingly, by attaching the light source unit to the light source main board via the hook, the light source main board and each LED element can be electrically connected. In this case, a part of the circuit of the light source main board can be provided on the auxiliary board side, so that the circuit configuration of the light source main board can be simplified.

  In the above description, the case where the illumination device of the present invention is used for an image reading device has been described as an example. However, in the present invention, for example, a plurality of point light sources are arranged in a line to form a rod-shaped light source. Can also be widely applied.

It is the figure which looked at the longitudinal section of the image reading device from the front side (front side), and is a figure explaining an optical system. It is the figure which looked at the longitudinal section of the image reading device from the front side (front side), and is a figure explaining a drive system. FIG. 4 is a top view for explaining the relationship between a light source, the size of a document, and the position of the document at the time of image reading, and a diagram for explaining the case where the document size is A row and B row. It is a top view explaining the relationship between a light source, the size of a document, and the position of the document at the time of image reading, and is a figure explaining the case where a document size is inch size. (A) is an enlarged view of the light source unit at the rearmost end in FIGS. 3 and 4. (B) is the AA arrow line view of (a). (C) is a BB line arrow directional view of (a).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Illuminating device, 11 ... Image reading device, 12 ... Light source, 13 ... Imaging lens, 14 ... CCD (solid-state image sensor), 15 ... Driving device (moving device), 25 ... For light sources Main board (main board), 71 to 74... Hook (holder), H1... Housing, L1 to L22... LED element (light source element), P ... predetermined pitch, 19, M1. U1 …… Light source unit

Claims (6)

In a lighting device comprising: a light source that irradiates an image surface of a document in a line; and a moving device that relatively moves the light source and the document so that the document moves in a direction perpendicular to the line.
(1). The light source is
a. It is configured by aligning multiple light source elements in a line,
b. And integrally hold the single light source element and a single light guide lens in a single first housing, a first type which emits light from the light source device via the light guide lens a light source Uni Tsu city of,
Two or more of the light source elements and these light source elements and the same number of the light guide lens holding integrally the second housings in a ring of a single, to emit light from the light source device via the light guide lens A second type of light source unit adapted to,
Is composed of multiple combinations,
c. The first type of the light source element and the second type of the main board to the circuit for supplying electric power to the light source element is formed of a light source unit of the light source unit, wherein the first type of light source unit and the second type Of light source units can be attached individually and detachably,
(2). An electrode is formed on a surface of the main board on which the first and second light source units are attached, and a holder for detachably positioning the first and second light source units for each of the first and second light source units. Formed,
(3). The holder is formed for each of the first-type and second-type light source units, and includes a plurality of elastically deformable hooks formed so as to face each other.
(4). The plurality of hooks are formed with claw portions that protrude so as to narrow the interval with other hooks facing the tip,
(5). When the first type and the second type light source unit are pushed between the hooks facing each other beyond the hooks of the hook and pressed onto the main board, the first type and the second type The electrode installation surface of the light source unit is in contact with the electrode on the main board, the light source element and the circuit on the main board are conducted, and held on the main board by the elastic force of the hook.
A lighting device characterized by that. The light sources are aligned at a predetermined pitch that allows the plurality of light source elements to irradiate the image surface of the original document uniformly along the line direction.
The lighting device according to claim 1. The light source is configured by the number of the light source elements corresponding to the irradiation width of the original with the minimum irradiation width in the line direction of the original to be irradiated and the same number of the light guide lenses. Having one or two types of light source units;
The illumination device according to claim 1, wherein The light source includes the first type or the first type constituted by the number of the light source elements corresponding to the difference in the irradiation width and the same number of the light guide lenses of the plurality of types of the originals having different irradiation widths to be irradiated. Having two light source units,
The illumination device according to claim 1, wherein The light source element is an LED element;
The lighting device according to any one of claims 1 to 4 , wherein An illumination device that irradiates the image surface of the document while relatively moving the light source and the document; and an imaging lens that forms an image by reflected light that is emitted from the illumination device and reflected by the image surface of the document; In an image reading apparatus provided with a solid-state imaging device,
An image reading apparatus, wherein the illumination apparatus is the illumination apparatus according to any one of claims 1 to 5.

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