JP4329585B2 - Image reading device - Google Patents

Description

  The present invention relates to an image reading apparatus in which an ADF frame that houses an automatic document conveyance mechanism is provided on an upper surface of an apparatus main body through a hinge member so as to be freely opened and closed.

  Image reading devices used in scanners, facsimiles, copiers, etc. include flatbed systems that place an original on a platen glass and read the image, and image reading by feeding multiple originals in sequence. There is a thing of the sheet through method to perform. The flat bed method is realized by a flat bed scanner (hereinafter referred to as “FBS”), and the sheet-through method is mainly realized by an auto document feeder (hereinafter referred to as “ADF”).

FIG. 7 is a schematic front view showing a conventional PPF (Plain Paper Facsimile ) type image reading apparatus 100 equipped with an ADF and reading an image only by a sheet through method. The image reading apparatus 100 is mainly a plain paper. Applicable to facsimile. As shown in the figure, an image reading apparatus 100 includes an apparatus main body 102 in which an image reading means 101 is stored, and an ADF frame 103 in which an ADF (not shown) is stored. The original document P is separated from the uppermost sheet one by one and fed into the ADF, and the image on the surface of the original document P passes through the slit glass 105 disposed at the reading position X of the apparatus main body 102 and is read by the image reading means 101. And is discharged to the paper discharge tray 106.

  As shown in FIG. 7, the apparatus main body 102 includes a bottom frame 107 for fixing the image reading unit 101 below the ADF, and a frame cover 108 provided on the bottom frame 107 and constituting a paper discharge tray and the like. It consists of. An insertion hole 109 is formed in the side frame side end of the bottom frame 107 in the vertical direction, and the ADF frame 103 is fixed to the upper surface of the apparatus main body 102 via a hinge member 110 inserted into the insertion hole 109. Thus, the ADF frame 103 can be opened and closed in the side surface direction. The ADF frame 103 opened in the lateral direction is fixed by a lock mechanism (not shown) at a position indicated by a dotted line in the drawing, and in that state, the user performs maintenance work such as jam processing or cleaning of paper dust accumulated on the slit glass 105. Is supposed to do.

  On the other hand, FIG. 8 is a schematic perspective view showing a conventional MFP (Multi-Function Peripherals) type image reading device 120 equipped with an FBS and performing image reading in a flat bed system. The image reading device 120 is a facsimile machine. Used in a multi-function machine that integrates functions such as a copy, a scanner, and a printer (see Patent Document 1). As shown in the figure, the image reading apparatus 120 includes an apparatus main body 122 having a platen glass 121 provided on the upper surface, and an original conveying mechanism (ADF), and an original pressing plate provided on the upper surface of the apparatus main body 122 so as to be opened and closed. 123. The apparatus main body 122 includes a hollow bottom frame 125 whose upper surface is open and a frame cover 126 to which the platen glass 121 is fixed and covers the upper surface of the bottom frame, and moves below the platen glass 121 into the bottom frame 125. Thus, image reading means (not shown) for reading an image of the document is provided. A through hole and a fitting hole for fitting the hinge member 124 are formed in the rear side end portions of the frame cover 126 and the bottom frame 125, respectively, and the original is passed through the hinge member 124 fitted into the through hole and the fitting hole. The back side of the pressing plate 123 is attached to the upper surface of the apparatus main body 122. As a result, the document pressing plate 123 rotates so as to open the upper part of the platen glass 121, so that it is easy to place or remove the document on the platen glass 121.

  The document pressing plate 123 is equipped with a document transport mechanism. When the document transported by the document transport mechanism passes through the slit glass 128 from the opening 127 on the lower surface of the document pressing plate 123, an image in the apparatus main body 122 is displayed. The image is read by the reading means. Here, as described above, since the document pressing plate 123 rotates with the back side as a pivot point, the opening 127, that is, the conveyance path, may be displaced with respect to the reading line of the image reading means below the slit glass 128. Yes, an adjustment mechanism is required to correct this. Conventionally, of the pair of hinge members 124 provided on the left and right sides of the document pressing plate 123, for example, the left hinge member 124 is fixed and the right hinge member 124 can be adjusted in the front-rear direction of the apparatus. By adjusting the position 124, the position of the opening 127 of the document pressing plate 123 is adjusted with respect to the reading line of the image reading means.

JP-A-11-020957

However, as shown in FIG. 7 , the PPF type image reading apparatus 100 is such that the ADF frame 103 rotates to the side of the apparatus main body 102, so that maintenance work of the image reading apparatus 100 is performed from the right hand side of the apparatus main body 102. However, since the document tray 104 and the like are arranged on the right hand side, there is a problem that the user's clothes such as cuffs may be caught and the operation is difficult. In addition, even when the user's dominant hand is the left hand, there is a problem that it is difficult to work from the right hand side.

  On the other hand, when the ADF frame 103 can be rotated with the back side of the apparatus as a pivot point, as with the image reading apparatus 120, it is necessary to adjust the position of the conveyance path and the reading line of the image reading means. Since the ADF frame 103 does not have a width in the left-right direction like the document pressing plate 123 of the MFP type image reading apparatus 120, it is difficult to adjust the position by providing a pair of hinge members on the left and right.

  The present invention has been made in view of such a problem. In an image reading apparatus in which an ADF frame in which an ADF is stored is provided on an upper surface of an apparatus main body so as to be openable and closable. It is an object of the present invention to provide means for enabling the position of an ADF frame to be adjusted with respect to a reading line of an image reading means.

In order to achieve the above object, an image reading apparatus according to the present invention has an automatic document transport system that transports a document from a document tray to a discharge tray through a reading position of the device body on an upper surface of a device body having an image scanning unit. ADF frame for housing the mechanism comprises a base portion attached to the apparatus main body and the frame support portion is mounted for openably through a pivotally mounted hinge member formed by rotating fixed to one end of the ADF frame in the image reading apparatus, prior SL ADF frame, the convex portion for positioning the ADF frame in contact with the upper surface of the apparatus main body is provided in at least three places, and the mounting hole is formed in the base of the hinge member A boss part that is inserted into the mounting hole and has an upper end surface protruding from the upper surface of the base part, and a fixing tool that protrudes in a hook shape from the upper end surface is provided on the boss part. By attaching, the base part of the hinge member is attached to the upper surface of the apparatus main body so as to be movable up and down within a predetermined range, the attachment hole is drilled in the attachment plate constituting the base part, and the attachment hole A stepped portion that is stepped down from the upper surface of the mounting plate is formed in the periphery, and the boss portion is formed in a concave shape on the upper surface of the apparatus main body and has a depth dimension substantially equal to the thickness dimension of the mounting plate. It is provided protruding from the bottom of the recess .

In the image reading apparatus according to the present invention, an insertion hole is formed on the upper surface of the apparatus main body, and an insertion piece that is smaller in cross section than the insertion hole and is inserted into the insertion hole is a base portion of the hinge member. And the boss portion is formed smaller in cross section than the mounting hole, and the mounting plate is formed smaller in cross section than the mounting recess, and a positioning pin projects from the upper surface of the apparatus body, The ADF frame is formed with a positioning hole for fitting with the positioning pin .

  According to the image reading apparatus of the present invention, the ADF frame is provided with convex portions that contact the upper surface of the apparatus main body to position the ADF frame, and the base of the hinge member is provided on the apparatus main body. Since it is attached to the upper surface so as to be movable up and down within a predetermined range, the position of the ADF frame can be adjusted with respect to the reading line of the image reading means, and the reading accuracy of the image reading apparatus can be kept good.

  Further, according to the present image reading apparatus, the attachment hole is formed in the base portion of the hinge member, and the apparatus main body is provided with the boss portion that is inserted through the attachment hole and the upper end surface projects from the upper surface of the base portion. Since the fixture that protrudes in a hook shape from the upper end surface is fixed to the boss part, install a gap between the mounting plate and the bottom of the mounting recess, and between the mounting plate and the upper end face of the boss part. The plate can be allowed to rattle up and down by this gap. Therefore, even if a dimensional error or mounting error occurs in the hinge member, etc., the mounting plate slightly moves up and down to absorb the error, so that the three convex portions come into contact with the upper surface of the apparatus main body. Thus, the ADF frame can be closed. Thus, the same effect as that of the image reading apparatus according to the first aspect can be obtained.

Further, according to the image reading apparatus, the insertion hole is formed on the upper surface of the apparatus main body, and the insertion piece that is smaller in cross section than the insertion hole and is inserted into the insertion hole protrudes from the base of the hinge member. The Further, the boss portion is formed smaller in cross section than the mounting hole, and the mounting plate is formed smaller in cross section than the mounting recess. Since the positioning pin protrudes from the upper surface of the apparatus main body and the positioning hole for fitting with the positioning pin is formed in the ADF frame, the positioning pin is fitted into the positioning hole when the ADF frame is closed. The position of the ADF frame is fixed in the horizontal direction. Accordingly, by preventing the front end portion of the ADF frame from being laterally displaced in the horizontal direction, it is possible to prevent the document from being skewed and to maintain good reading accuracy of the image reading apparatus.

  Hereinafter, an image reading apparatus according to an embodiment of the present invention will be described with reference to the drawings. The image reading apparatus 1 is a PPF type image reading apparatus that is equipped with an ADF and performs image reading only by a sheet-through method. FIG. 1 is a schematic perspective view showing the external appearance of the image reading apparatus 1. As shown in the figure, the image reading apparatus 1 includes an apparatus main body 3 having a slit glass 2 disposed on the upper surface thereof, and an ADF provided on the upper surface 3a of the apparatus main body 3 through a hinge member 4 so as to be opened and closed. A frame 5, a document tray 6 for placing the document P to be read, a paper discharge tray 7 for receiving the document P that has been read, and a front surface of the apparatus body 3 are provided to operate the image reading device 1. And an operation panel 8 for this purpose.

  FIG. 2 is a schematic longitudinal sectional view showing the internal configuration of the image reading apparatus 1. As shown in the figure, in the image reading apparatus 1, a scanner unit (image reading means) 9 is accommodated in the apparatus main body 3, and an ADF 10 is accommodated in the ADF frame 5. The ADF 10 separates the original P set on the original tray 6 one by one from the uppermost sheet and feeds it to the conveyance path 11. The image on the surface of the original P is read by the scanner unit 9 at the reading position X and discharged. The paper is discharged to the paper tray 7.

  The scanner unit 9 is a so-called reduction optical system CCD reading unit that irradiates light to the original P through the slit glass 2 and converts the reflected light from the original P into an electrical signal to read an image. Although not shown, a light source, a reflection mirror, a condensing lens, and a CCD image sensor are arranged in a substantially rectangular parallelepiped casing 12. Both ends of the scanner unit 9 are fixed immediately below the reading position X in the apparatus main body 3 by holding members (not shown).

  The ADF frame 5 is a resin frame formed in a hollow box shape, and the ADF 10 can be accommodated therein. As shown in FIGS. 1 and 2, the ADF 10 separates and conveys the uppermost sheet Pt from the bundle of documents P, and a substantially horizontal U-shaped conveyance path 11 that connects the document tray 6 and the discharge tray 7. A paper feeding unit 13 that feeds out to the path 11, a transport roller 14 that is appropriately disposed in the transport path 11 and transports the document P downstream, and a transport assist that guides the document P read at the reading position X to the discharge port 15. The rib 16 and the projection 17 for positioning the ADF frame 5 at a predetermined height with respect to the apparatus main body 3 are provided.

  As shown in FIG. 1, the ADF frame 5 has an end on the back side attached to the upper surface 3 a of the apparatus main body 3 via the hinge member 4, and opens front, that is, the bottom 5 a of the apparatus main body 3. It can be opened and closed to be exposed to the front side. This is because when the document jam occurs inside the ADF 10, the jammed document P can be easily removed by opening the ADF frame 5 and exposing the conveyance path 11, and performing maintenance of the image reading apparatus 1. In this case, the operation is facilitated by opening the ADF frame 5. Here, the front opening of the ADF frame 5 allows the bottom 5a of the ADF frame 5 to be exposed to the front side of the image reading apparatus 1, and thus has an advantage that maintenance work can be easily performed. As shown in FIG. 2, it is also possible to remove the document P jammed in the ADF frame 5 by opening only the upper cover K constituting the ADF frame 5 and exposing the conveyance path 11. is there.

  As described above, since the ADF frame 5 can be opened and closed, when the opened ADF frame 5 is closed, the ADF frame 5 is inclined and the leading end thereof is lifted, and the document P is skewed or the scanner unit 9 is moved. Therefore, it is necessary to position the ADF frame 5 at a fixed position with respect to the apparatus main body 3 so that the read image quality due to the above does not deteriorate. Accordingly, in this embodiment, as shown in FIG. 1, a pair of left and right convex portions 17 projecting from the bottom surface 5a are provided at the tip end side of the ADF frame 5, that is, the end portion opposite to the hinge member 4, and Corresponding to each convex portion 17, concave portions 18 are formed at two locations on the upper surface 3 a of the apparatus main body 3. Here, the protruding lengths of the convex portions 17 from the bottom surface 5a of the ADF frame 5 are equal to each other. In addition, as shown in FIG. 1, a convex portion 17 is also provided at a substantially central portion on the base end side of the ADF frame 5, that is, the attachment side by the hinge member 4, and the bottom surface of the ADF frame 5 of the convex portion 17. The protruding length from 5a is equal to the protruding length of each convex portion 17 on the tip side. As a result, the ADF frame 5 is closed at a predetermined height horizontally by closing the ADF frame 5 so that all the three convex portions 17 on the distal end side and the proximal end side are in contact with the upper surface 3a of the apparatus main body 3. It is possible to hold. The convex portions 17 for positioning the ADF frame 5 in the height direction as described above may be provided at three or more locations on the bottom portion 5a of the ADF frame 5, but at least three points are required to position the ADF frame 5 horizontally. It is sufficient to position with 3 and it is preferable to use 3 from the viewpoint of cost reduction. In addition, the position where each convex portion 17 is provided is not limited to this embodiment as long as the three convex portions 17 are not arranged in a straight line. In order to hold, it is preferable to provide at two ends on the more distal end side of the ADF frame 5 and one central portion on the more proximal end side as in this embodiment.

  One of the two convex portions 17 on the tip side is formed of a magnet, and an iron plate is disposed on the bottom of one concave portion 18 corresponding to the convex portion 17. Thus, when the ADF frame 5 is closed, the one convex portion 17 is attracted to the bottom portion of the one concave portion 18 by its magnetic adhesion force. At this time, the current flowing between the one convex portion 17 and the one concave portion 18 is detected by an open / close detection sensor (not shown) housed in the ADF frame 5 to detect the opening / closing of the ADF frame 5. It has become.

  FIG. 3 is an exploded perspective view in which the vicinity of the hinge member 4 in FIG. 1 is enlarged. As shown in FIGS. 1 to 3, on the upper surface 3 a of the apparatus main body 3, a portion corresponding to the ADF frame 5 is provided with a slit glass 2 disposed at a reading position X by the scanner unit 9, and the slit glass 2. A conveyance roller 14 for conveying the document P to the head, an attachment recess 19 for attaching the hinge member 4, a pair of left and right bosses 21 projecting from the bottom of the attachment recess 19 and formed with screw holes 20, An insertion hole 22 is provided in the bottom of the mounting recess 19 for inserting the hinge member 4 into the apparatus main body 3.

  As shown in FIG. 3, the mounting recess 19 is formed by forming the back side end of the upper surface 3 a of the apparatus body 3 in a concave shape in order to attach the hinge member 4 substantially flush with the upper surface 3 a of the apparatus body 3. And has a substantially rectangular shape in plan view. The boss portion 21 is inserted into the hinge member 4 to position the hinge member 4 with respect to the apparatus main body 3 and to screw a regulating screw 28 described later. As shown in FIGS. 3 and 4, the boss portion 21 has a substantially cylindrical shape, and protrudes at two locations on the bottom portion of the mounting recess 19, and its lower end portion is formed to protrude into the apparatus main body 3. ing.

  The positioning pins 23 prevent the ADF frame 5 from being displaced in the horizontal direction with respect to the apparatus main body 3 when the ADF frame 5 is closed. That is, in the present invention, as will be described later, the ADF frame 5 is not fixed in position with respect to the apparatus main body 3, and the rear side end portion is attached to the upper surface 3 a of the apparatus main body 3 so as to be front-opened. Thus, as the rotation radius with the hinge member 4 as a fulcrum is long, the horizontal displacement is easy to occur. Accordingly, the positioning pin 23 protrudes inward of the concave portion 18 on the upper surface 3 a of the apparatus main body 3, and correspondingly, the positioning hole 24 having a shape that fits the positioning pin 23 on the bottom surface 5 a of the ADF frame 5. Is forming. Thereby, when the ADF frame 5 is closed, the positioning pins 23 are fitted into the positioning holes 24, and the ADF frame 5 is held immovably in the horizontal direction. The position and number of the positioning pins 23 and the positioning holes 24 can be arbitrarily changed. However, as in this embodiment, the positioning pins 23 and the positioning holes 24 are provided at positions farther from the mounting position of the ADF frame 5 to the apparatus main body 3. Is preferable because the ADF frame 5 can be held more reliably.

  As shown in FIG. 3, the hinge member 4 has a pair of left and right frame support portions 25 that support one end side of the ADF frame 5, and a base portion 26 that is attached to the apparatus main body 3, and is rotatable via a hinge pin 27. The base 26 of the hinge member 4 is attached to the upper surface 3a of the apparatus main body 3 via a regulating screw (fixing tool) 28 so as to be movable up and down within a predetermined range.

  The base portion 26 is attached to an upper surface 3a of the apparatus main body 3, a pair of left and right hinge pin support pieces 30 that protrude upward from the upper surface of the attachment plate 29 and respectively support both ends of the hinge pin 27, and an attachment The plate 29 is provided so as to protrude downward from the bottom surface and has an insertion piece 31 to be inserted into the apparatus main body 3 from the insertion hole 22. Each hinge pin support piece 30 is formed with a pin insertion hole 32 through which the hinge pin 27 is inserted, and the long hinge pin 27 is inserted into and fixed to each of the pin insertion holes 32 so that the right and left A hinge pin 27 is installed between the hinge pin support pieces 30. The insertion piece 31 is inserted into the insertion hole 22 to position the hinge member 4 with respect to the apparatus main body 3 to some extent. The insertion piece 31 is formed slightly smaller than the insertion hole 22, and a slight gap is generated between the insertion piece 31 and the insertion hole 22 when the insertion piece 31 is inserted into the insertion hole 22. As a result, the hinge member 4 is allowed to rattle by this gap.

As shown in FIG. 3, the mounting plate 29 is a flat plate that is substantially rectangular in plan view, and has a boss insertion hole (mounting hole) 33 through which each boss portion 21 is inserted, and the periphery of each boss insertion hole 33. And a stepped portion 34 formed by stepping down from the upper surface of the mounting plate 29. The planar shape of the mounting plate 29 is slightly smaller than the planar shape of the mounting recess 19 of the apparatus body 3, and the thickness dimension thereof is substantially equal to the depth dimension of the mounting recess 19. By fitting and attaching to the mounting recess 19, the mounting plate 29 is not easily displaced in the horizontal direction. Further, the thickness dimension of the stepped portion 34 of the mounting plate 29 is slightly smaller than the protruding height at which each boss portion 21 protrudes from the bottom of the mounting recess 19. As a result, as shown in FIG. 4, when the boss portions 21 are inserted through the boss insertion holes 33, the upper end surfaces of the boss portions 21 protrude from the upper surface of the stepped portion 34. Although not shown in detail in the drawing, the diameter of each boss insertion hole 33 is slightly larger than the outer diameter of each boss part 21, and when the boss part 21 is inserted into the boss insertion hole 33, the boss insertion hole 33 is inserted. A slight gap is formed between the inner peripheral surface of the hole 33 and the outer peripheral surface of the boss portion 21. As a result, the hinge member 4 is allowed to have a slight backlash in the horizontal direction by the gap.

  As shown in FIG. 4, the stepped portion 34 is provided with a step d between the upper end surface of the boss portion 21 and the upper surface of the mounting plate 29, so that the mounting plate 29 is inserted into each boss insertion hole 33. In a state in which is inserted, it is possible to move in the vertical direction along the boss portions 21 by the level difference d. As a means for providing a step d between the upper end surface of the boss portion 21 and the upper surface of the mounting plate 29, the upper surface of the mounting plate 29 can be formed by stepping down the upper surface of the mounting plate 29 as in this embodiment. It is also possible to increase the position of the end face. That is, without forming the step-down portion 34, the protrusion height at which each boss portion 21 protrudes from the bottom of the attachment recess 19 is made larger than the thickness of the attachment plate 29, whereby the upper end surface of the boss portion 21 and the attachment plate A step d can be provided between the upper surfaces of 29.

  The regulating screw 28 determines the upper limit position of the vertical movement of the mounting plate 29. As shown in FIG. 4, the screw portion 35 shorter than the depth of the screw hole 20 of the boss portion 21 and the lower end portion are bosses. And a screw head 36 having a diameter larger than that of the portion 21. The restriction screw 28 is screwed into the screw hole 20 of the boss portion 21 until the lower end portion of the screw head 36 is brought into contact with the upper end surface of the boss portion 21, and the lower end portion of the screw head 36 is above the boss portion 21. It is in a state protruding from the end surface in a bowl shape. The attachment plate 29 cannot move further upward by contacting the lower end portion of the screw head 36 protruding in the hook shape. The movement range of the mounting plate 29 can be widened by turning the restriction screw 28 to increase the protruding length from the boss portion 21, and conversely, turning the restriction screw 28 to protrude from the boss portion 21. It can be narrowed by reducing the length.

  As a means for determining the upper limit of the vertical movement of the mounting plate 29, in addition to the present embodiment, for example, the entire screw head 36 is formed larger in diameter than the boss portion 21, or the screw head 36 and the boss portion 21 are formed. It is also possible to interpose a plate member such as a washer having a diameter larger than that of the boss portion 21 between the upper end surfaces of the, and to restrict the upward movement of the mounting plate 29 by this plate member. Further, as a means for fixing the regulating screw 28 to the boss portion 21, in addition to forming the screw hole 20 in the boss portion 21 as in this embodiment, a screw insertion hole penetrating the boss portion 21 is formed, A restriction screw 28 longer than the length of the boss portion 21 is inserted into the screw insertion hole, and a nut is screwed into a lower end portion of the restriction screw 28 protruding from the lower end of the boss portion 21. It is also possible to fix.

  In this way, by attaching the hinge member 4 to the upper surface 3a of the apparatus main body 3 so as to be movable up and down within a predetermined range, a slight backlash is allowed to occur on the attachment side of the ADF frame 5. Therefore, even when a dimensional error or a mounting error occurs in the hinge member 4, when the ADF frame 5 is closed, the mounting plate 29 moves up and down by an amount corresponding to the error, so that each convex portion of the ADF frame 5 17 are both securely abutted against the upper surface 3a of the apparatus body 3, and the ADF frame 5 can be closed horizontally. As a result, the document P is accurately read by the scanner unit 9.

  As shown in FIG. 3, the frame support portion 25 is an arm member in which a pin insertion hole 37 through which the hinge pin 27 is inserted is formed at a base end formed in an arc shape. Although not shown in detail in the drawing, the distal ends of the frame support portions 25 are fixed to the ADF frame 5 with screws or the like, and the hinge pins 27 are inserted into the pin insertion holes 37 at the proximal end. Thereby, the ADF frame 5 is rotatable about the hinge pin 27 as a fulcrum. In addition, as described above, the convex portion for holding the ADF frame 5 at a predetermined height from the upper surface 3 a of the apparatus main body 3 by contacting the upper surface of the mounting plate 29 at the substantially central portion of the frame support portion 25. 17 is provided.

  Hereinafter, the vertical movement of the hinge member 4 when a dimensional error or an attachment error occurs in the hinge member 4 or the like will be described. 4 to 6 are diagrams showing the vertical movement of the hinge member 4. FIG. 4 shows the state where the ADF frame 5 is closed from the side of the image reading apparatus 1, and FIG. FIG. 6 shows a state in which the ADF frame 5 is closed when the error occurs in the hinge member 4 and the like. FIG. It is the schematic longitudinal cross-sectional view seen from. In this embodiment, an allowable error for the error generated in the hinge member 4 or the like is set as d. That is, when the ADF frame 5 is closed and the three projections 17 provided on the bottom surface 5a are in contact with the top surface 3a of the apparatus main body 3, as shown in FIG. 19 and between the mounting plate 29 and the upper end surface of the boss portion 21, d / 2 gaps are generated, and the mounting plate 29 is d / 2 above and below in the vertical direction by this gap. The rattling is allowed. Therefore, even if the error occurs in the hinge member 4 or the like, as shown in FIG. 5, the mounting plate 29 slightly moves up and down to absorb the error, so that the three projections 17 are connected to the apparatus main body 3. It is possible to close the ADF frame 5 so as to abut on the upper surface 3a. At this time, as shown in FIG. 6, the ADF frame 5 has two points A and B where the convex portions 17 of the bottom surface 5 a abut against the upper surface 3 a of the apparatus body 3, and the convex portions 17 of the frame support portion 25. Is positioned in the vertical direction by a total of three points C, which are in contact with the upper surface of the mounting plate 29, and is held horizontally at a predetermined height from the apparatus main body 3. Of course, the vertical movement of the mounting plate 29 is not limited to the state shown in FIGS. 4 to 6, and appropriately changes according to the error of the hinge member 4 and the like. The ADF frame 5 is not shown in detail in the drawing, but each of the points where the outer peripheral surface of each boss portion 21 comes into contact with the inner peripheral surface of each boss insertion hole 33 and the outer peripheral surface of the positioning pin 23 are the positioning holes 24. Positioning in the horizontal direction by a total of three points, which are in contact with the inner peripheral surface, prevents lateral displacement.

1 is a schematic perspective view showing an image reading apparatus 1 according to an embodiment of the present invention. FIG. 2 is a schematic longitudinal sectional view showing an internal structure of the image reading apparatus 1. The disassembled perspective view which expanded the hinge member 4 vicinity in FIG. FIG. 3 is a schematic longitudinal sectional view of the state where the ADF frame 5 is closed as viewed from the side of the image reading apparatus 1. FIG. 3 is a schematic longitudinal sectional view of the state where the ADF frame 5 is closed when the error occurs in the hinge member 4 and the like, as viewed from the side of the image reading apparatus 1. FIG. 3 is a schematic longitudinal sectional view of the state in which the ADF frame 5 is closed when an error occurs in the hinge member 4 and the like, as viewed from the back side of the image reading apparatus 1. FIG. 10 is a schematic front view showing an image reading apparatus 100 according to a conventional example. FIG. 10 is a schematic perspective view showing another image reading apparatus 120 according to a conventional example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image reader 3 Apparatus main body 3a Upper surface 3a (apparatus main body)
4 Hinge member 5 ADF frame 6 Document tray 7 Paper discharge tray 9 Scanner unit 10 Automatic document transport mechanism 17 Convex part 21 Boss part 23 Positioning pin 24 Positioning hole 25 Frame support part 26 Base part 28 Restriction screw (fixing tool)
33 Boss insertion hole (mounting hole)
P Document X Reading position

Claims (2)

An ADF frame that houses an automatic document transport mechanism for transporting a document from the document tray to the discharge tray through the reading position of the device body is fixed to one end side of the ADF frame on the upper surface of the device body having the image reading unit. in the image reading apparatus and the base attached to the apparatus main body and the frame support portion is provided to be freely opened and closed through a hinge member formed by pivoted rotatably to be,
Before SL ADF frame, the convex portion for positioning the ADF frame in contact with the upper surface of the apparatus main body is provided in at least three places, and,
A mounting hole is formed in the base portion of the hinge member, and a boss portion that is inserted through the mounting hole and protrudes from the upper surface of the base portion is provided in the apparatus main body. By fixing the fixing tool protruding to the base, the base of the hinge member is attached to the upper surface of the apparatus main body so as to be vertically movable within a predetermined range,
The mounting hole is formed in a mounting plate that constitutes the base, and a stepped portion that is stepped down from the upper surface of the mounting plate is formed around the mounting hole, and the boss portion is an upper surface of the apparatus main body. An image forming apparatus characterized in that is formed in a concave shape so as to protrude from the bottom of the mounting recess having a depth dimension substantially equal to the thickness dimension of the mounting plate . While an insertion hole is formed on the upper surface of the apparatus main body, an insertion piece that is formed smaller in cross section than the insertion hole and is inserted into the insertion hole is protruded from the base of the hinge member,
The boss portion is formed smaller in cross section than the mounting hole, and the mounting plate is formed smaller in cross section than the mounting recess,
The image reading apparatus according to claim 1 , wherein a positioning pin protrudes from an upper surface of the apparatus main body, and a positioning hole is formed in the ADF frame to be fitted with the positioning pin .

Images