JP4890799B2 - Scanning apparatus and image reading apparatus - Google Patents

Description

  The present invention relates to an image reading apparatus employed in a multi-function device (MFD) or the like, and more particularly to a structure of a scanning device incorporated in the image reading apparatus.

  A multifunction peripheral (MFD), which is a multi-function device having a copy function, a scanner function, and other functions, generally includes an image reading device that reads a document. This image reading apparatus is equipped with a scanning device for scanning an original, and some of the scanning devices include a contact image sensor.

  FIG. 8 is a diagram schematically showing the structure of a main part of a conventional scanning device. As shown in the figure, the scanning device 1 generally includes a contact image sensor 2 and a holder 3 that holds the contact image sensor 2. The holder 3 is moved in the direction of the arrow 9 via a driving device (not shown). Therefore, the contact image sensor 2 scans the document while being moved in the direction of the arrow 9. (For example, see Patent Document 1 and Patent Document 2).

JP-A-10-243181 Japanese Patent Laid-Open No. 11-165852

  Incidentally, the contact image sensor 2 is assembled to the holder 3 in the manufacturing process of the scanning device 1. In this assembling work, the operator grasps the contact image sensor 2, and the engagement pins 4, 5 protruding from the contact image sensor 2 are engaged with the engagement holes 6, 7 provided in the holder 3, respectively. It is to fit in. Usually, the contact image sensor 2 is provided with two engagement pins 4 and 5 side by side on an imaginary line 8 in the longitudinal direction, and the retainer 3 has two engagement holes 6 and 7 corresponding thereto. Is provided. For this reason, it is generally not easy and skill is required for the operator to quickly fit the two engagement pins 4 and 5 simultaneously into the two engagement holes 6 and 7 while holding the contact image sensor 2. It is.

  Specifically, the operator grasps the contact image sensor 2 and first rotates it relative to the cage 3 in the direction of the arrow 10, and then engages the engagement pins 4, 5 and the engagement hole 6. The contact image sensor 2 is moved relative to the holder 3 in the direction of the arrow 11 in a state in which the positions of 7 and 7 are aligned. Then, the operator fits the engagement pins 4 and 5 and the engagement holes 6 and 7 while moving the contact image sensor 2 in this way, and in the state where both are fitted, the contact image sensor 2 is moved to the above position. Rotate in the opposite direction to arrow 10. As a result, the contact image sensor 2 is fitted into the cage 3.

  That is, in this assembling work, the operator rotates the contact image sensor 2 in the direction of the arrow 10, and the contact image sensor 2 in order to fit the pair of engagement pins 4 and 5 into the engagement holes 6 and 7, respectively. To move the contact image sensor 2 in the direction of the arrow 11 and to rotate the contact image sensor 2 in the direction opposite to the arrow 10 in order to fit the contact image sensor 2 to the cage 3, There is a problem in that the work efficiency is lowered and the manufacturing cost of the scanning device is increased. Further, since the assembly work is complicated, the operator's hand may touch the sensing surface 12 of the contact image sensor 2 during the work, and the sensing surface 12 may be contaminated with sebum or dust. There was also a problem. That is, if the sensing surface 12 is contaminated with sebum, dust, or the like, the cleaning effort for removing these increases. Furthermore, when sebum adheres to the sensing surface 12, it is difficult to return to the same state as the sensing surface 12 before the attachment, and as a result, the quality of the read image may be deteriorated.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a scanning device that is easy to assemble, prevents contamination, and is inexpensive, and an image reading device employing the scanning device.

(1) In order to achieve the above object, a scanning device according to the present invention includes a housing, a light source attached to the housing, and a contact image having a plurality of light receiving elements arranged in parallel in the longitudinal direction of the housing. A sensor, and a holder that surrounds and holds the contact image sensor so that the upper surface is opened and the light source and the light receiving element are exposed on the upper surface. An engagement convex portion extending in the longitudinal direction is formed on one of a pair of end surfaces facing the longitudinal direction of the housing and the cage. The contact image sensor is fitted to the other of the pair of end faces facing the longitudinal direction of the housing and the cage by the relative movement of the engagement convex portion only in the vertical direction. Engagement recesses that are surrounded and held by the cage are provided. The engagement recess is formed by a fitting groove whose upper end is released and extends in the up-down direction, and the engagement protrusion is allowed to move in the up-down direction while positioning the case in the short direction of the case. The part is slidably supported.

The contact image sensor is assembled to the housing such that the light source and the light receiving element are exposed on the upper surface of the housing. Then, the contact image sensor is held in the surroundings by being fitted into the cage. At this time, the upper surface of the contact image sensor is exposed on the upper surface of the cage. Specifically, the contact image sensor is assembled to the cage in the following manner. That is, the operator holds the housing of the contact image sensor and inserts it into the cage from above, for example. Thereby, the contact image sensor is easily accommodated and held in the holder. More specifically, since the engagement convex portion and the fitting groove are provided on the pair of end surfaces facing the longitudinal direction of the housing and the cage, the operator moves the contact image sensor along the vertical direction . Then, the engagement protrusion and the fitting groove are fitted to each other only by fitting into the cage, and as a result, the contact image sensor is fitted into the cage. In this state, the contact image sensor is positioned in the short direction.

As described above, the operator can fit the contact image sensor into the holder by operating only in the vertical direction while holding the contact image sensor. However, it is sufficient for the operator to grip only the side surface (the wall surface in the short direction) of the casing when performing the assembly work. Therefore, the operator's hand is reliably prevented from coming into contact with the upper surface of the contact image sensor, and the upper surface of the contact image sensor (the surface on which the light source and the light receiving device are arranged) is not stained in the assembly work. Absent.

( 2 ) It is preferable that the engaging convex portion is extended on the end surface in the longitudinal direction of the cage, and the engaging concave portion is provided on the end surface in the longitudinal direction of the casing.

( 3 ) Further, the engaging convex portion may be extended on the longitudinal end surface of the casing, and the engaging concave portion may be provided on the longitudinal end surface of the cage.

( 4 ) Further, the engaging convex portion is extended to a base portion provided on the end surface in the lateral direction of the casing, and the engaging concave portion is provided on the end surface in the longitudinal direction of the cage. Also good.

( 5 ) In particular, the engaging projection has a cylindrical protrusion, and the outer diameter of the cylindrical protrusion and the inner diameter of the fitting groove are such that the cylindrical protruding piece is in the fitting groove. On the other hand, it is preferable to set so as to fit without shaking in the short direction. In this configuration, since the structure of the engaging convex portion and the engaging concave portion is very simple, the scanning device can be configured at low cost.

( 6 ) In order to achieve the above object, an image reading apparatus according to the present invention is attached to a casing having an opening on the upper surface and the casing so as to be exposed to the opening. A contact glass plate in which a placement surface is defined, a guide shaft provided in the casing, and disposed close to the inner surface of the contact glass plate and supported at the center by the guide shaft and along the guide shaft And the above-described scanning device provided so as to be slidable. In particular, the sliding stroke of the engaging convex portion with respect to the fitting groove is set to be larger than the distance between the inner surface of the casing and the lower surface of the cage.

Since this image reading apparatus includes the above-described scanning device, the assembling work of the contact image sensor to the holder is very simple. In this assembling work, the upper surface of the contact image sensor (the light source and the light receiving device). The surface on which the measures are placed is not soiled. In addition, since the scanning apparatus is configured at low cost, the image reading apparatus can be reduced in price. In addition, since the sliding stroke of the engaging convex portion with respect to the fitting groove is set to be larger than the distance between the inner surface of the casing and the lower surface of the cage, the image reading device is being conveyed. In this case, even if the scanning device is displaced with respect to the casing due to vibration or other factors, the scanning device does not fall off the guide shaft.

  According to the present invention, since the assembling operation of the scanning device is very simple, the scanning device and the image reading apparatus using the scanning device are manufactured at low cost.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

  FIG. 1 is an external perspective view of an image reading apparatus 30 according to an embodiment of the present invention.

  The image reading device 30 can be used, for example, as a scanner unit of a multi-function device (MFD) having a printer function and a scanner function integrally, and as an image reading unit of a copying machine. However, in the present invention, the printer function is an arbitrary mechanism. For example, the image reading device 30 may be configured as a flatbed scanner (FBS) having only a scanner function.

  As shown in the figure, the image reading apparatus 30 includes a reading table 31 that functions as an FBS, and a document pressing cover 33 is attached to the reading table 31 so as to be freely opened and closed. The document pressing cover 33 includes an auto document feeder (ADF) 32. The reading platform 31 includes a substantially rectangular parallelepiped main body frame 34 (casing), a contact glass plate 35 provided on the top surface (upper surface) of the main body frame 34, and an image reading unit 36 incorporated in the main body frame 34. . The document is placed on the contact glass plate 35. When the document pressing cover 33 is closed, the document is fixed by the document pressing cover 33. The image reading unit 36 moves below the contact glass plate 35 along the contact glass plate 35, thereby reading an image from the original.

  An operation panel 37 is provided on the front side of the reading table 31. The operation panel 37 includes various operation buttons and a liquid crystal display unit. The image reading device 30 operates according to an instruction from the operation panel 37. When the image reading device 30 is configured as an MFD, a computer can be connected to the image reading device 30. In that case, the image reading apparatus 30 can operate not only by an instruction from the operation panel 37 but also by an instruction transmitted from the computer via a scanner driver or the like.

  As described above, the document pressing cover 33 includes the ADF 32 that continuously conveys documents from the document tray to the discharge tray. In the conveyance process by the ADF 32, the document passes through the platen 38, and the image reading unit 36 reads an image from the document below the platen 38. However, in the present embodiment, this ADF 32 may be omitted.

  FIG. 2 is a plan view of the reading table 31 and shows the internal structure of the reading table 31. FIG. 3 is a cross-sectional view of the reading mounting table 31.

As shown in FIGS. 1 and 3, the main body frame 34 of the reading table 31 includes a container-like lower frame 39 whose upper surface is open, and an upper cover 42 having an opening 41 on the upper surface 40. The main body frame 34 is configured by fitting the upper cover 42 onto the frame 39. The contact glass plate 35 is attached to the upper cover 42 so as to be exposed to the opening 41. The surface 95 of the contact glass plate 35 constitutes a document placement surface, and the opening 41 defines the document placement surface.

  As shown in FIG. 2, the image reading unit 36 is disposed in the lower frame 39. Both the lower frame 39 and the upper cover 42 are made of synthetic resin. The lower frame 42 includes a base portion 43 constituting a bottom plate, a side wall 44 rising from the periphery of the base portion 43, and a partition plate 45, which are integrally formed. The partition plate 45 partitions a portion where the image reading unit 36 is disposed and a portion where the substrate of the operation panel 37 is disposed. The lower frame 39 includes support ribs for supporting the contact glass plate 35, bosses for screwing various members, through holes for electrical wiring, and the like. However, since these are appropriately designed according to the embodiment of the reading table 31, detailed description thereof is omitted.

  As shown in FIG. 2, the image reading unit 36 includes a CIS unit 50 and a carriage 51 (scanning device), a guide shaft 52, and a belt driving mechanism 53. The image reading unit 36 includes a roller unit 58 (see FIG. 3) not shown in the figure. As shown in FIG. 3, the roller unit 58 abuts on the back surface 75 of the contact glass plate 35 and supports smooth movement of the CIS unit 50. The CIS unit 50 is a so-called contact type image sensor. The CIS unit 50 irradiates the original with light and receives reflected light from the original, and converts the received light into an electrical signal. As will be described in detail later, the CIS unit 50 includes an elongated rectangular parallelepiped casing 70, and the casing 70 is fitted into the carriage 51. The carriage 51 moves below the contact glass plate 35 (see FIGS. 1 and 3).

  Specifically, the carriage 51 is fitted to the guide shaft 52. The guide shaft 52 is constructed over the width direction of the lower frame 39. Here, the “width direction of the lower frame 39” is a direction perpendicular to the longitudinal direction of the casing 70 of the CIS unit 50 and along the lower surface of the contact glass plate 35 (that is, a direction perpendicular to the paper surface in FIG. 3). It is. Hereinafter, the direction (direction perpendicular to the paper surface in FIG. 3) is referred to as a “short direction”. The carriage 51 is driven by a belt drive mechanism 53 and slides on the guide shaft 52 to move. The carriage 51 holds the CIS unit 50 and urges it so as to be in close contact with the contact glass plate 35. The means for urging the carriage 51 is known and will be described later. As described above, the CIS unit 50 held by the carriage 51 is pressed against the contact glass plate 35 and moved in the short direction along the contact glass plate 35.

  As shown in FIG. 3, the carriage 51 is mounted with the CIS unit 50 so as to be carried on the upper side thereof. A shaft receiving portion 54 is formed on the lower surface of the carriage 51 so as to be fitted over the guide shaft 52 from above. The shaft receiving portion 54 and the guide shaft 52 are fitted to each other, and the carriage 51 is slidable in the axial direction of the guide shaft 52 while being supported by the guide shaft 52. Further, a belt gripping portion 55 projects downward from the side of the shaft receiving portion 54. The belt gripping portion 55 grips a timing belt 61 of a belt driving mechanism 53 described later. As a result, the timing belt 61 and the carriage 51 are connected. Then, the driving force is transmitted from the belt driving mechanism 53 to the carriage 51, so that the carriage 51 moves on the guide shaft 52.

  Also, spring receivers 56 are formed at two locations on the left and right sides of the carriage 51 on which the CIS unit 50 is mounted. The spring receiver 56 holds the coil spring 57 while positioning it. That is, the coil spring 57 is interposed between the CIS unit 50 and the carriage 51. As described above, the CIS unit 50 is urged toward the contact glass plate 35 by the coil spring 57 and pressed against the lower surface thereof.

  In the present embodiment, the bottom of the lower cover 39 of the main body frame 34 has an uneven shape as shown in FIG. A predetermined gap 49 is formed between the inner bottom surface 47 (inner surface of the casing) of the lower cover 39 and the lower surface 48 of the carriage 51 with the carriage 51 carried on the guide shaft 52. ing.

  As shown in FIG. 3, the roller unit 58 is provided at both ends of the CIS unit 50. The roller unit 58 includes a roller that rolls in the short direction, and this roller is in contact with the back surface 75 of the contact glass plate 35. Therefore, when the CIS unit 50 moves in the short direction, the roller rolls along the contact glass plate 35 accordingly. Since the roller unit 58 is provided, the CIS unit 50 moves smoothly along the contact glass plate 35 even when the CIS unit 50 is pressed against the lower surface of the contact glass plate 35.

  FIG. 4 is a plan view of the reading mounting table 31 and shows a schematic configuration of the belt driving mechanism 53.

  As shown in FIG. 4, the belt drive mechanism 53 includes a drive pulley 59, a driven pulley 60, a timing belt 61 wound around these, and a motor (not shown). The timing belt 61 is an endless belt having teeth formed inside. The timing belt 61 is configured to make a circumferential motion when the motor rotates the driving pulley 59.

  As shown in the figure, the drive pulley 59 is disposed at the left rear of the lower frame 39. The timing belt 61 wound around the drive pulley 59 extends to the front side of the lower frame 39 and is wound around an intermediate pulley 62 disposed in front of the guide shaft 52. Further, the timing belt 61 is bent at a substantially right angle, extends along the guide shaft 52 to the right end of the lower frame 39, and is wound around a driven pulley 60 disposed near the right end of the lower frame 39. That is, the timing belt 61 is constructed in a substantially L shape as shown in FIG. The portion between the driven pulley 60 and the intermediate pulley 62 of the timing belt 61 wound in this way, that is, the portion along the guide shaft 52 is gripped by the belt gripping portion 55 of the carriage 51, thereby The timing belt 61 and the carriage 51 are connected. Of course, as the timing belt 61, in addition to the endless belt, an endless belt in which both end portions of the belt are fixed to the carriage 51 may be employed.

  FIG. 5 is an enlarged perspective view of the above-described scanning device, and shows details of how to attach the CIS unit 50 and the carriage 51 (cage).

  The CIS unit 50 includes the casing 70 and a light source and a light receiving element provided in the casing 70. The CIS unit 50 is fitted and fixed to the carriage 51 as will be described later.

  The housing 70 is made of, for example, a synthetic resin, and is formed in an elongated rectangular parallelepiped shape as shown in FIG. The housing 70 contains the light source and the light receiving element. The upper surface 74 of the housing 70 faces the back surface 75 of the contact glass plate 35 (see FIG. 3). Therefore, the light source and the light receiving element are also in close proximity to the back surface 75 of the contact glass plate 35.

  The light source typically includes an LED (Light Emitting Diode) and a light guide 73. This LED is not shown in the figure, but is disposed in the inner part of the housing 70. The light guide 73 is typically made of a transparent synthetic resin and extends in the entire longitudinal direction of the housing 70. The light guide 73 is exposed on the upper surface 74 of the housing 70, and light emitted from the LEDs is guided to the entire longitudinal direction of the housing 70 by the light guide 73. As a result, the light emitted from the LEDs is distributed substantially evenly over the entire length of the housing 70 and is irradiated onto the document.

  In the present embodiment, the housing 70 is provided with a plurality of light receiving elements. Each light receiving element is disposed on the inner bottom of the housing 70, and is arranged in parallel in the longitudinal direction of the housing 70. Each light receiving element includes a condenser lens 72. The condenser lens 72 is exposed on the upper surface 74 of the housing 70. The light irradiated and reflected on the original is condensed by the condenser lens 72 and received by the light receiving element. This light receiving element is a photoelectric conversion element, and outputs an electrical signal based on the received light. This electric signal is an image signal of the image shown on the document.

  A protrusion 106 (engagement convex portion) is formed on an end surface 105 (opposing surface) in the longitudinal direction of the casing 70. This protrusion 106 is a cylindrical protrusion in this embodiment. The protrusion 106 is formed integrally with the housing 70 and protrudes by a predetermined length in the longitudinal direction. In addition, the housing 70 includes a positioning unit 107. The positioning portion 107 is formed in a block shape and protrudes from the side surface 108 of the casing 70 in the short direction. The positioning unit 107 includes a positioning groove 109. The positioning groove 109 is fitted into a positioning projection 110 provided on the carriage 51.

  On the other hand, the carriage 51 is made of, for example, a synthetic resin and is formed in an elongated rectangular parallelepiped shape having an open upper surface, as shown in FIG. The carriage 51 functions as a holder that holds the CIS unit 50. A fitting groove 112 (engaging recess) is provided on an end surface 111 (opposing surface) in the longitudinal direction of the carriage 51. In the present embodiment, the fitting groove 112 extends a predetermined length in the vertical direction (one direction), and the upper end of the fitting groove 112 is open. The width dimension of the fitting groove 112 (that is, the width direction dimension) corresponds to the outer diameter dimension of the protrusion 106. For this reason, when the protrusion 106 is fitted in the fitting groove 112, the protrusion 106 can freely move in the vertical direction with respect to the fitting groove 112. However, the protrusion 106 moves in the short direction. Is regulated and positioned.

  The length of the fitting groove 112 is set so that the protrusion 106 can move larger than the dimension of the gap 49 (see FIG. 3) with respect to the fitting groove 112. That is, the sliding stroke of the protrusion 106 with respect to the fitting groove 112 is set to be larger than the gap 49 between the inner bottom surface 47 of the lower cover 39 and the lower surface 48 of the carriage 51.

  Further, the carriage 51 is provided with a recess 56 at the bottom thereof. The recess 56 constitutes the above-described spring receiving portion 56 (see FIG. 3), and the coil spring 57 is fitted into the spring receiving portion 56. When the CIS unit 50 is fitted in the carriage 51, the lower surface of the casing 70 of the CIS unit 50 contacts the upper end of the coil spring 57. In other words, the CIS unit 50 is always elastically biased upward in the carriage 51. As a result, the CIS unit 50 is biased to the back surface 75 of the contact glass plate 35 as described above. The carriage 51 is provided with ribs, holes and the like for improving the rigidity as the structure or for positioning the CIS unit 50 with certainty. However, since these are appropriately designed according to the embodiment of the CIS unit 50, the detailed description thereof is omitted.

  In the image reading apparatus 30 according to the present embodiment, the scanning device is assembled in the following manner.

  In the CIS unit 50, the light source and the light receiving element are assembled to the casing 70 so that the ride guide 73 and the condenser lens 72 are exposed on the upper surface 74 of the casing 70. The CIS unit 50 is enclosed and held as described above by being fitted into the carriage 51. At this time, the upper surface of the CIS unit 50 (the upper surface 74 of the housing 70) is exposed on the upper surface of the carriage 51. Specifically, the CIS unit 50 is assembled to the carriage 51 in the following manner. That is, the operator holds the casing 70 of the CIS unit 50 and fits it into the carriage 51 from above to below. Thereby, the CIS unit 50 is easily accommodated and held in the carriage 51.

  As described above, the operator can easily fit the CIS unit 50 into the carriage 51 by operating only in one direction (vertical direction) while holding the CIS unit 50. The unit 50 is positioned in the short direction. That is, the assembling work of the CIS unit 50 to the carriage 51 is very simple, and the operator can hold only the side surface (the wall surface in the short direction) of the casing 70 when performing the assembling work. It is enough. Therefore, in the conventional scanning apparatus, when assembling the CIS unit to the carriage, the operator carefully works so as not to touch the upper surface of the CIS unit (that is, the surface where the light guide or the condenser lens is exposed). Although it was necessary, in this embodiment, the operator's hand is reliably prevented from coming into contact with the upper surface of the CIS unit 50 (the upper surface 74 of the housing 70). There is an advantage that the condenser lens 72 and the light guide 73 are prevented from being contaminated. As a result, the assembly cost of the scanning device is reduced, and consequently the manufacturing cost of the image reading device 30 is reduced.

  In particular, in the present embodiment, the CIS unit 50 is fitted into the carriage 51 by being moved only from above to below, so that the work for assembling the CIS unit 50 to the carriage 51 is very simple for the operator.

  Further, in the present embodiment, in order to assemble the CIS unit 50 to the carriage 51, the projection 106 made of the columnar protruding piece is provided on the CIS unit 50 side, and on the other hand, the fitting groove 112 is provided on the carriage 51 side. Yes. Thereby, the structure for assembling the CIS unit 50 to the carriage 51 is further simplified, and there is an advantage that the scanning device can be configured at a lower cost.

  Further, as shown in FIG. 3, with the carriage 51 holding the CIS unit 50 attached to the lower frame 39, the slide stroke of the protrusion 106 with respect to the fitting groove 112 (see FIG. 5) 39 is larger than the gap 49 between the inner bottom surface 47 of the carriage 39 and the lower face 48 of the carriage 51, so that the CIS unit 50 and the carriage 51 are moved relative to the lower frame 39 due to vibration and other factors during the conveyance of the image reading device 30. Even if it is displaced, there is an advantage that the carriage 51 does not fall off the guide shaft 52.

  Next, a modified example of this embodiment will be described.

  FIG. 6 is an enlarged perspective view of the scanning device according to the first modification of the present embodiment, and shows details of how to attach the CIS unit 50 and the carriage 51.

  The scanning device according to this modification is different from the scanning device according to the above embodiment. In the scanning device according to the above embodiment, the protrusions 106 are formed on the end surfaces 105 on both sides in the longitudinal direction of the casing 70 of the CIS unit 50. In the present modification, the fitting grooves 112 are provided on the end surfaces 111 on both sides in the longitudinal direction of the carriage 51. On the other hand, in this modification, the fitting surfaces 112 are fitted on the end surfaces 105 on both sides in the longitudinal direction of the casing 70 of the CIS unit 50. A groove 114 is provided (only the right fitting groove 114 is shown in the figure), and projections 115 are formed on the end surfaces 111 on both sides in the longitudinal direction of the carriage 51. When the carriage 51 and the CIS unit 50 are fitted in the vertical direction, the projection 115 and the fitting groove 114 are fitted, and the CIS unit 50 is positioned and held on the carriage 51. In addition, about another structure, it is the same as that of the said embodiment.

  The protrusion 115 formed on the carriage 51 has the same shape as the protrusion 106 (see FIG. 5) provided on the housing 70 in the embodiment, but protrudes inside the carriage 51. Further, the fitting groove 114 is provided on each end face 105 in the longitudinal direction of the casing 70, and is formed so that the end face 105 is cut out inward. The fitting groove 114 extends in the vertical direction on the both end faces 105, and the lower end of the fitting groove 114 is opened. The width dimension of the fitting groove 114 (that is, the width direction dimension) corresponds to the outer diameter dimension of the protrusion 115. Therefore, as in the above embodiment, when the protrusion 115 is fitted in the fitting groove 112, the protrusion 106 can freely move in the vertical direction with respect to the fitting groove 112. Movement in the short direction is restricted and positioned. In the figure, the fitting groove provided on the end face on the left side in the longitudinal direction of the casing 70 is not shown, but the fitting groove 114 provided on the end face 105 on the right side in the longitudinal direction of the casing 70 It is the same composition.

  Next, a second modification of the present embodiment will be described.

  FIG. 7 is an enlarged perspective view of a scanning device according to a second modification of the present embodiment, and details of how to attach the CIS unit 50 and the carriage 51 are shown.

  The scanning device according to this modification is different from the scanning device according to the above embodiment. In the scanning device according to the above embodiment, the protrusions 106 are formed on the end surfaces 105 on both sides in the longitudinal direction of the casing 70 of the CIS unit 50. Whereas, the fitting grooves 112 are provided in the end surfaces 111 on both sides in the longitudinal direction of the carriage 51, whereas in the present modification, the protrusions are formed on the right end surface 105 in the longitudinal direction of the casing 70 of the CIS unit 50. 106 is formed, the fitting groove 112 is provided on the end surface 111 on the right side in the longitudinal direction of the carriage 51, and the protrusion 116 is provided on the end surface 113 on the left side in the longitudinal direction of the carriage 51. A fitting groove (not shown) into which the projection 116 can be fitted is provided on the left end surface in the longitudinal direction. When the carriage 51 and the CIS unit 50 are fitted in the vertical direction, the projection 106 and the fitting groove 112, the projection 116 and the fitting groove (not shown) are fitted, and the CIS unit is fitted. 50 is positioned and held by the carriage 51. In addition, about another structure, it is the same as that of the said embodiment.

  The fitting groove (not shown) has the same configuration as that of the fitting groove 114 according to the first modification, and the fitting groove is arranged so that the protrusion 116 provided on the carriage 51 is fitted from below. The lower end of is open. Further, the protrusion 116 has the same shape as the protrusion 106 (see FIG. 5) provided on the housing 70 in the embodiment, but protrudes inside the carriage 51. That is, the protrusion 116 has the same configuration as the protrusion 115 according to the first modification. Therefore, also in this modification, as in the above embodiment, when the projection 106 is fitted into the fitting groove 112 and when the projection 116 is fitted into the fitting groove (not shown), The protrusions 106 and 116 can freely move in the vertical direction with respect to the fitting groove 112 and the like, but the movement in the short direction is restricted and positioned.

  Next, a third modification of the present embodiment will be described.

  In the embodiment and each modification, the protrusions 106 and the like are formed on one of the longitudinal end surfaces 105 and 111 of the casing 70 and the carriage 51, and the longitudinal end surfaces 105 and 111 and the like are formed. The fitting groove 112 or the like is provided on the other side. However, the protrusion 106 and the fitting groove 112 and the like do not need to be directly provided on the end face 105 or the like in the longitudinal direction.

  For example, in FIG. 5, the protrusion 106 is directly provided on the end surface 105 in the longitudinal direction of the housing 70. As a third modification of the embodiment, the protrusion 106 is an end surface of the positioning portion 107 (base portion). 117 may be provided to protrude. In that case, the position of the fitting groove 112 provided on the end surface 111 in the longitudinal direction of the carriage 51 is changed in accordance with the position of the projection 106. However, in addition to the protrusion 106 being formed on the positioning portion 107, a base portion may be provided on the lateral side surface 108 of the housing 70, and the base portion may be formed on the end surface in the longitudinal direction. Of course.

  The present invention can be applied to an image reading apparatus employed in a copying machine or a multifunction machine.

FIG. 1 is an external perspective view of an image reading apparatus according to an embodiment of the present invention. FIG. 2 is a plan view of the reading stage of the image reading apparatus according to the embodiment of the present invention. FIG. 3 is a cross-sectional view of the reading stage of the image reading apparatus according to the embodiment of the present invention. FIG. 4 is a plan view of the reading stage of the image reading apparatus according to the embodiment of the present invention, and shows the structure of the belt driving mechanism. FIG. 5 is an enlarged perspective view of the scanning device of the image reading apparatus according to the embodiment of the present invention. FIG. 6 is an enlarged perspective view of the scanning device of the image reading apparatus according to the first modification of the embodiment of the present invention. FIG. 7 is an enlarged perspective view of the scanning device of the image reading apparatus according to the second modification of the embodiment of the present invention. FIG. 8 is a diagram schematically showing the structure of a main part of a conventional scanning device.

DESCRIPTION OF SYMBOLS 30 ... Image reading device 34 ... Main body frame 36 ... Image reading unit 39 ... Lower frame 40 ... Upper surface 41 ... Opening 47 ... Inner bottom surface 48 ... Lower surface of a carriage 49 ... Gap 50 ... CIS unit 51 ... Carriage 52 ... Guide shaft 54 ... Shaft receiving part 56 ... Spring receiving part 57 ... Coil spring 70 ... Case 72 ... Condensing lens 73 ... Light guide 74 ... Upper surface of housing 75 ... Back surface of contact glass plate 95 ... Front surface of contact glass plate 105 ... End surface in longitudinal direction 106 ... Protrusion 107 ··· Positioning portion 108 ··· Short side surface 111 ··· Longitudinal end surface 112 ··· Fitting groove 113 ··· Left end surface 114 ··· Fitting groove 115 ··· Projection 116 The end face of the ... projections 117 ... the positioning portion

Claims (6)

A contact image sensor having a housing, a light source attached to the housing, and a plurality of light receiving elements arranged in parallel in the longitudinal direction of the housing;
A scanning device comprising a holder that holds the contact image sensor so that the upper surface is opened and the light source and the light receiving element are exposed on the upper surface;
An engagement convex portion extending in the longitudinal direction is formed on either one of the pair of end faces facing the longitudinal direction of the housing and the cage,
The engagement convex portion is fitted to the other of the pair of end surfaces facing the longitudinal direction of the housing and the cage by being relatively moved only in the vertical direction, and the contact image sensor is fitted to the cage. An engagement recess to be held in the surrounding area is provided,
The engaging recess is formed by a fitting groove whose upper end is released and extends in the vertical direction, and the engagement convexity is provided so as to allow the vertical movement while positioning the casing in the short direction of the casing. Scanning device that supports the part slidably. The engagement convex portion is extended on the end face in the longitudinal direction of the cage,
The scanning device according to claim 1 , wherein the engaging recess is provided on an end surface of the casing in the longitudinal direction. The engagement convex portion extends to the end face in the longitudinal direction of the housing,
The scanning device according to claim 1 , wherein the engagement concave portion is provided on an end surface in the longitudinal direction of the cage. The engaging convex portion extends to a base portion provided on an end surface of the casing in the lateral direction,
The scanning device according to claim 1 , wherein the engagement concave portion is provided on an end surface in the longitudinal direction of the cage. The engaging convex part has a cylindrical protrusion ,
Inner diameter of the outer diameter and the fitting groove of said cylindrical protrusion is claims the cylindrical protrusion is configured to fit without looseness to the lateral direction with respect to the fitting groove Item 5. The scanning device according to any one of Items 1 to 4 . A casing having an opening on the top surface;
A contact glass plate that is attached to the casing so as to be exposed at the opening, and a document placement surface is defined by a peripheral edge of the opening;
A guide shaft provided in the casing;
The scanning according to any one of claims 1 to 5 , wherein the scanning is arranged in the vicinity of the inner surface of the contact glass plate and supported at the center by the guide shaft and slidable along the guide shaft. With the device,
The image reading apparatus, wherein a sliding stroke of the engaging convex portion with respect to the fitting groove is set larger than a distance between an inner surface of the casing and a lower surface of the cage.

Images