JP5135176B2 - Image reading apparatus and image forming apparatus having the same - Google Patents

Description

  The present invention relates to an image reading apparatus for optically reading an image of a document, and an image forming apparatus such as a copying machine, a facsimile apparatus, or a multifunction machine including the same.

  In general, an image forming apparatus such as a copying machine optically reads an image of an original by an image reading device and prints it on a sheet-like recording material such as copy paper based on the read image data, or reads the read image. Data is transmitted to a receiving facsimile machine or the like via communication means.

  Further, the image reading device irradiates the original with light from a light source in a carriage that moves in a sub-scanning direction orthogonal to the main scanning direction of the original placed on the transparent plate, and reflects the light flux reflected from the original. After being guided in a predetermined direction by a mirror accommodated in the carriage, the reflected light beam is imaged by a lens, and an image is read by a CCD (image sensor) arranged at the imaging position.

  FIG. 10 is a plan view schematically showing such an image reading apparatus 100. As shown in FIG. 10, the image reading apparatus 100 is fitted to a round bar-shaped guide rail 101 extending along the sub-scanning direction so that a bearing 104 provided on one end 103 side of the carriage 102 in the main scanning direction can slide. On the other hand, on the guide plate 105 extending along the sub-scanning direction, the other end portion 106 side of the carriage 102 in the main scanning direction is slidable and stretched so as to be movable along the sub-scanning direction. A belt holding part 108 on one end 103 side of the carriage 102 is fixed to a use belt (timing belt) 107, and the carriage 102 is moved along the guide rail 101 by the drive belt 107.

However, in such an image reading apparatus 100, a fitting gap is provided between the guide rail 101 and the bearing 104 in order to slide the carriage 102 with respect to the round bar-shaped guide rail 101. For this reason, such an image reading apparatus 100 is fitted to the carriage 102 between the guide rail 101 and the bearing 104 due to vibrations generated when the carriage 102 is moved in the sub-scanning direction or variations in sliding resistance. A swinging operation corresponding to the gap (the rotation operation of the carriage 102 in both the forward and reverse directions indicated by the arrow R1 in a plan view of FIG. 10 ) occurs, and the read image is distorted. Reading was difficult.

  In order to solve such a problem, as shown in FIG. 11, the guide rail 112 is pressed against the fixed slide member 114 of the carriage 113 by the pressure slide member 111 biased by the spring 110, and the guide rail 112 is fixedly slid. A technique is known in which the member 114 and the pressure slide member 111 are slidably sandwiched, and rattling between the carriage 113 and the guide rail 112 and the swinging motion of the carriage 113 caused by this rattling are eliminated ( Patent Document 1).

  As shown in FIG. 12, a spiral groove 121 is formed on the outer peripheral surface of the guide shaft 120, a coil spring 122 is engaged in the spiral groove 121, and this coil spring 122 is connected to the inner peripheral surface of the bearing 124 of the carriage 123. A technique is known in which, by compressing, a fitting portion gap between the guide shaft 120 and the bearing 124 of the carriage 123 is eliminated, and vibration when the carriage 123 moves is reduced (see Patent Document 2).

Further, as shown in FIG. 13, in order to avoid an increase in the size of the entire apparatus, in the home position, the distance between the pair of bearings 132 of the carriage 131 that fits into the guide rail 130 is narrowed (see FIG. 13A). During scanning of the document (during image reading), the distance between the pair of bearings 132 of the carriage 131 is expanded by the force of the spring 133 (see FIG. 13B), and the gap between the bearing 132 and the guide rail 130 is fitted. A technique is known in which the amount of swing of the carriage 131 caused by this is reduced (see Patent Document 3).
JP 2003-158614 A (refer to FIG. 1 in particular) Japanese Patent Laid-Open No. 5-145705 (refer to FIG. 1 in particular) JP 2007-178506 A (refer to FIG. 6 in particular)

  However, the techniques shown in FIGS. 10 to 13 are new in that the structure is complicated and the product price of the image reading apparatus is increased in order to prevent or suppress the swinging motion of the carriages 113, 123, and 131. Problems arise.

  SUMMARY OF THE INVENTION An object of the present invention is to prevent the carriage from swinging without causing an increase in product price due to a complicated structure.

According to the first aspect of the present invention, a carriage in which an optical unit for reading an image is accommodated is driven by a driving belt stretched around a plurality of pulleys, and a sub-orthogonal direction perpendicular to the main scanning direction of a document placed on a transparent plate. The present invention relates to an image reading apparatus in which an image of a document moved in the scanning direction and placed on the transparent plate is read via the optical unit in the carriage. In the present invention, one end of the carriage in the main scanning direction is slidably engaged with a first guide member extending along the sub-scanning direction, and is fixed to the driving belt. The other end side of the carriage in the main scanning direction is elastically sandwiched between a pair of non-movable members positioned so as to be spaced apart from each other in the vertical direction and guided by the pair of non-movable members. Thus, it slides along the sub-scanning direction. Further, (1) one of the pair of non-movable member, the transparent plate, (2) the other of said pair of non-movable member, extends along the sub-scanning direction, the other end of the carriage It is the 2nd guide member which supports slidably from the downward direction. An elastic member that is in contact with the transparent plate in a compressed state is fixed to a portion facing the transparent plate on the other end side of the carriage. Further, the portion of the carriage facing the second guide member on the other end side is pressed against and contacted with the second guide member by the elastic force of the elastic member. Further, when the carriage that moves in the sub-scanning direction is viewed in plan, and the movement of the carriage that rotates in both forward and reverse directions is a swinging operation, when the carriage moves in the sub-scanning direction, The other end portion side of the carriage is connected to the one end portion of the carriage at the sliding contact portion between the elastic member and the transparent plate and the sliding contact portion between the other end portion side of the carriage and the second guide member. The frictional force acts in a direction that is delayed from the side, and the frictional force that prevents the carriage from swinging is applied.

According to a second aspect of the present invention, a carriage in which an optical unit for reading an image is accommodated is driven by a driving belt stretched around a plurality of pulleys, and a sub-portion orthogonal to the main scanning direction of a document placed on a transparent plate. The present invention relates to an image reading apparatus in which an image of a document moved in the scanning direction and placed on the transparent plate is read via the optical unit in the carriage. In the present invention, one end of the carriage in the main scanning direction is slidably engaged with a first guide member extending along the sub-scanning direction, and is fixed to the driving belt. The other end side of the carriage in the main scanning direction is elastically sandwiched between a pair of non-movable members positioned so as to be spaced apart from each other in the vertical direction and guided by the pair of non-movable members. Thus, it slides along the sub-scanning direction. Further, (1) one of the pair of non-movable member, the transparent plate, (2) the other of said pair of non-movable member, extends along the sub-scanning direction, the other end of the carriage It is the 2nd guide member which supports slidably from the downward direction. And the 1st elastic member which contacts the said transparent plate in the state compressed is fixed to the part facing the said transparent plate by the said other end part side of the said carriage. A second elastic member that is in contact with the second guide member in a compressed state is fixed to a portion of the carriage that faces the second guide member on the other end side. Further, when the carriage that moves in the sub-scanning direction is viewed in plan, and the movement of the carriage that rotates in both forward and reverse directions is a swinging operation, when the carriage moves in the sub-scanning direction, The other end side of the carriage is connected to the one end of the carriage at the sliding contact portion between the first elastic member and the transparent plate and the sliding contact portion between the second elastic member and the second guide member. A frictional force acting in a direction that is delayed from the part side and a frictional force that prevents the carriage from swinging is applied.

According to a third aspect of the present invention, a carriage in which an optical unit for reading an image is accommodated is driven by a driving belt stretched around a plurality of pulleys, and a sub-orthogonal direction perpendicular to the main scanning direction of a document placed on a transparent plate. The present invention relates to an image reading apparatus in which an image of a document moved in the scanning direction and placed on the transparent plate is read via the optical unit in the carriage. In the present invention, one end of the carriage in the main scanning direction is slidably engaged with a first guide member extending along the sub-scanning direction, and is fixed to the driving belt. The other end side of the carriage in the main scanning direction is elastically sandwiched between a pair of non-movable members positioned so as to be spaced apart from each other in the vertical direction and guided by the pair of non-movable members. Thus, it slides along the sub-scanning direction. Further, (1) one of the pair of non-movable member, the transparent plate, (2) the other of said pair of non-movable member, extends along the sub-scanning direction, the other end of the carriage It is the 2nd guide member which supports slidably from the downward direction. An elastic member that is in contact with the second guide member in a compressed state is fixed to a portion facing the second guide member on the other end side of the carriage. In addition, a sliding member that is pressed against the transparent plate by the elastic force of the elastic member and slidably contacts the transparent plate is fixed to a portion of the carriage facing the transparent plate on the other end side. ing. Further, when the carriage that moves in the sub-scanning direction is viewed in plan, and the movement of the carriage that rotates in both forward and reverse directions is a swinging operation, when the carriage moves in the sub-scanning direction, In the sliding contact portion between the elastic member and the second guide member and the sliding contact portion between the sliding member and the transparent plate, the other end portion side of the carriage is delayed from the one end portion side of the carriage. A frictional force acting in a direction and a frictional force that prevents the carriage from swinging is applied.

According to a fourth aspect of the present invention, a carriage in which an optical unit for image reading is accommodated is driven by a driving belt stretched around a plurality of pulleys, and a sub-portion orthogonal to the main scanning direction of a document placed on a transparent plate. The present invention relates to an image reading apparatus in which an image of a document moved in the scanning direction and placed on the transparent plate is read via the optical unit in the carriage. In the present invention, one end of the carriage in the main scanning direction is slidably engaged with a first guide member extending along the sub-scanning direction, and is fixed to the driving belt. The other end side of the carriage in the main scanning direction is elastically sandwiched between a pair of non-movable members positioned so as to be spaced apart from each other in the vertical direction and guided by the pair of non-movable members. Thus, it slides along the sub-scanning direction. Further, (1) one of the pair of immovable member is a top member of the second guide member extending along and the sub-scanning direction along the transparent plate, (2) of the pair of non-movable members The other is a lower piece of a second guide member that extends along the transparent plate and along the sub-scanning direction. An elastic member that is in contact with the upper piece in a compressed state is fixed to a portion of the carriage facing the upper piece on the other end side. A portion of the carriage facing the lower piece on the other end side is pressed against the lower piece by the elastic force of the elastic member to come into contact therewith. Further, when the carriage that moves in the sub-scanning direction is viewed in plan, and the movement of the carriage that rotates in both forward and reverse directions is a swinging operation, when the carriage moves in the sub-scanning direction, The sliding contact portion between the elastic member and the upper piece of the second guide member and the sliding contact portion between the other end portion side of the carriage and the lower piece of the second guide member are arranged on the carriage. A frictional force acting in a direction that delays the other end side of the carriage relative to the one end side of the carriage, and a frictional force that prevents the carriage from swinging.

According to a fifth aspect of the present invention, a carriage in which an optical unit for reading an image is accommodated is driven by a driving belt stretched around a plurality of pulleys, and a sub-orthogonal direction perpendicular to the main scanning direction of a document placed on a transparent plate. The present invention relates to an image reading apparatus in which an image of a document moved in the scanning direction and placed on the transparent plate is read via the optical unit in the carriage. In the present invention, one end of the carriage in the main scanning direction is slidably engaged with a first guide member extending along the sub-scanning direction, and is fixed to the driving belt. The other end side of the carriage in the main scanning direction is elastically sandwiched between a pair of non-movable members positioned so as to be spaced apart from each other in the vertical direction and guided by the pair of non-movable members. Thus, it slides along the sub-scanning direction. Further, (1) one of the pair of immovable member is a top member of the second guide member extending along and the sub-scanning direction along the transparent plate, (2) of the pair of non-movable members The other is a lower piece of a second guide member that extends along the transparent plate and along the sub-scanning direction. And the 1st elastic member which contacts the said upper piece in the compressed state is being fixed to the part facing the said upper piece by the said other end part side of the said carriage. A second elastic member that is in contact with the lower piece in a compressed state is fixed to a portion of the carriage opposite to the lower piece on the other end side. Further, when the carriage that moves in the sub-scanning direction is viewed in plan, and the movement of the carriage that rotates in both forward and reverse directions is a swinging operation, when the carriage moves in the sub-scanning direction, The sliding contact portion between the first elastic member and the upper piece of the second guide member and the sliding contact portion between the second elastic member and the lower piece of the second guide member are arranged on the carriage. A frictional force acting in a direction that delays the other end side of the carriage relative to the one end side of the carriage, and a frictional force that prevents the carriage from swinging.

According to a sixth aspect of the present invention, a carriage in which an optical unit for reading an image is accommodated is driven by a driving belt stretched around a plurality of pulleys, and a sub-ordinate orthogonal to the main scanning direction of an original placed on a transparent plate. The present invention relates to an image reading apparatus in which an image of a document moved in the scanning direction and placed on the transparent plate is read via the optical unit in the carriage. In the present invention, one end of the carriage in the main scanning direction is slidably engaged with a first guide member extending along the sub-scanning direction, and is fixed to the driving belt. The other end side of the carriage in the main scanning direction is elastically sandwiched between a pair of non-movable members positioned so as to be spaced apart from each other in the vertical direction and guided by the pair of non-movable members. Thus, it slides along the sub-scanning direction. Further, (1) one of the pair of immovable member is a top member of the second guide member extending along and the sub-scanning direction along the transparent plate, (2) of the pair of non-movable members The other is a lower piece of a second guide member that extends along the transparent plate and along the sub-scanning direction. An elastic member that is in contact with the lower piece in a compressed state is fixed to a portion facing the lower piece on the other end side of the carriage. The portion of the carriage facing the upper piece on the other end side is pressed against the upper piece by the elastic force of the elastic member. Further, when the carriage that moves in the sub-scanning direction is viewed in plan, and the movement of the carriage that rotates in both forward and reverse directions is a swinging operation, when the carriage moves in the sub-scanning direction, The sliding contact portion between the elastic member and the lower piece of the second guide member, and the sliding contact portion between the other end portion side of the carriage and the upper piece of the second guide member are arranged on the carriage. A frictional force acting in a direction that delays the other end side of the carriage relative to the one end side of the carriage, and a frictional force that prevents the carriage from swinging.

A seventh aspect of the present invention relates to an image forming apparatus, the image reading apparatus according to any one of the first to sixth aspects of the invention, and printing for printing on a recording material based on image data read by the image reading apparatus. Means.

  The image reading apparatus according to the present invention generates a frictional force between the carriage and the non-movable member only by moving the carriage held between the pair of non-movable members in the sub-scanning direction. Since it is possible to prevent the carriage from swinging by constantly acting in a direction that prevents movement in the direction, the apparatus structure is not complicated and the product price is not increased.

  Further, the image forming apparatus according to the present invention enables the printer unit to perform high-precision printing on the recording material based on the image data accurately read by the image reading apparatus according to the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Schematic configuration of image forming apparatus)
FIG. 1 is a diagram illustrating a schematic configuration of the image forming apparatus 1. As shown in FIG. 1, an image forming apparatus 1 includes an image reading device (scanner unit) 2 that reads an image of a document, image data read by the image reading device 2, and external equipment (facsimile device, personal computer, scanner, etc.). And a printer unit 3 that prints on a sheet-like recording material (copy paper, plastic film, etc.) S based on the image data transmitted from the computer.

(Printer part)
The printer unit 3 of the image forming apparatus 1 shown in FIG. 1 sends out one of a plurality of recording materials S stacked in a paper feeding cassette 4 to a recording material conveyance path 6 by a paper feeding means 5. The recording material S sent to the conveyance path 6 is conveyed by the conveyance roller pair 7 along the recording material conveyance path 6 to the registration roller pair 8. Then, the front end of the recording material S is pressed against the nip portion of the registration roller pair 8 to correct the skew of the recording material S, and the registration roller pair 8 sends the recording material S to the printing means 10 in accordance with the printing timing. An image is printed on the recording material S by the printing means 10, and the printed recording material S is discharged onto the paper discharge tray 12 by the discharge roller pair 11.

  Here, the printing means 10 may be either an electrophotographic type or an inkjet type.

  The electrophotographic printing means 10 is configured such that the exposure device 13 forms an electrostatic latent image on the photoreceptor 14 based on the image data read by the image reading device 2, and then the electrostatic latent image is developed by the developing device 15 with toner. The toner image is visualized as an image, the toner image on the photoreceptor 14 is transferred to the recording material S by the transfer device 16, and the toner image transferred to the recording material S is fixed by the fixing device 17. A cleaning device 18 that removes toner remaining on the photoconductor 14 after transfer and a static elimination device 20 that neutralizes the surface of the photoconductor 14 from which the toner has been removed by the cleaning device 18 are disposed around the photoconductor 14 in FIG. A charging device 21 that uniformly charges the surface of the photoreceptor 14 that has been neutralized by the static eliminating device 20 is disposed in order in the clockwise direction.

  The ink jet printing means 10 is controlled in operation based on image data read by the image reading device 2 by a discharge mechanism (not shown) that discharges ink in an ink tank (not shown) toward the recording material S. An image is printed on the recording material S by ink particles discharged from a nozzle of a discharge mechanism (not shown).

(First example of image reading apparatus)
2 to 7 show a first example of the image reading apparatus 2 constituting the image forming apparatus 1 shown in FIG. Among these, FIG. 2 is a plan view schematically showing the image reading apparatus 2. FIG. 3 is a structural diagram schematically showing the carriage 22 cut along the moving direction. FIG. 4 is a perspective view in which a part of the image reading device 2 is broken and the carriage 22 is viewed obliquely from above. FIG. 5 is a perspective view of the carriage 22 on one end 23 side as seen from the direction of arrow A in FIG. FIG. 6 is a plan view of one end portion 23 side of the carriage 22 with the guide rail (first guide member) 24 removed, showing the relationship between the driving belt 25 and the belt holding portion 26. (See FIGS. 4 and 5). 7 is a perspective view of the transparent plate (non-movable member) 27 partially cut away and shown on the other end 28 side of the carriage 22, and is a perspective view seen from the direction of arrow B in FIG. .

  Hereinafter, a first example of the image reading apparatus 2 will be described with reference to FIGS. 1 to 7.

  As shown in FIGS. 1 to 3, the image reading apparatus 2 is a rectangular transparent plate (contact glass, plastic plate) on which a document G is placed on an upper portion of a box-shaped frame 30 having a rectangular planar shape. Etc.) 27 is attached. Inside the frame 30, the carriage 22 accommodating the optical unit 31 is accommodated so that it can move from the home position (a predetermined position on the left end side in FIG. 2) in the sub-scanning direction (right direction in FIG. 2). ing. The optical unit 31 housed inside the carriage 22 includes a light source 32 for irradiating the original G with light via the transparent plate 27 and a plurality of mirrors 33 for reflecting and guiding the light beam reflected by the original G in a predetermined direction. And a lens 34 that forms an image of the light beam reflected by the plurality of mirrors 33, and a CCD (image sensor) 35 that reads image data imaged by the lens 34. Then, the carriage 22 moves from the home position in the sub-scanning direction, and the image of the original G on the transparent plate 27 is read by the optical unit 31 in the carriage 22.

  As shown in FIGS. 2, 4, and 5, one end portion 23 of the carriage 22 in the main scanning direction is a pair of bearings (guide rail engaging portions) fitted so as to be slidable on a round bar-shaped guide rail 24. 36 is formed apart from each other in the sub-scanning direction, and the belt holding portion 26 for holding the driving belt 25 is located at a position approximately at the center between the pair of bearings 36 and below the pair of bearings 36 (the driving belt 25 is It is formed at a position that does not interfere with the guide rail 24 or the like. Here, the guide rail 24 extends along the sub-scanning direction from the left side wall 30a to the right side wall 30b of the frame 30 as indicated by a two-dot chain line in FIG. The inner peripheral surface of the bearing 36 of the carriage 22 is fitted to the guide rail 24 with a slight gap. Further, as shown in FIG. 2, the driving belt 25 is an endless toothed belt (a toothed belt made of a synthetic rubber or polyurethane in which a core wire such as steel, glass fiber or aramid fiber is embedded. 2) and pulleys 37 and 38 arranged at one end (upper end in FIG. 2) along the main scanning direction of the frame 30 and at both ends along the sub-scanning direction of the frame 30. It is stretched and can be rotated in both forward and reverse directions by pulleys 37 and 38. In the belt holding portion 26 of the carriage 22, a groove 40 is formed along the sub-scanning direction so that the driving belt 25 can be inserted from above, and the opposite side surface of the groove 40 (facing the driving belt 25). A plurality of projections 43 and 44 are formed on both side surfaces 41 and 42, and the plurality of projections 43 and 44 formed on both side surfaces 41 and 42 are clamped in a state in which the driving belt 25 is elastically deformed (bite into). Then, the one end 23 side of the carriage 22 is securely fixed to the driving belt 25 (see FIG. 6). In FIG. 2, for convenience of explanation, the guide rail 24 and the pair of bearings 36 fitted to the guide rail 24 are indicated by a two-dot chain line.

  2, 3, and 7, the other end 28 side of the carriage 22 in the main scanning direction is a guide plate (second guide) that extends along the sub-scanning direction on the bottom surface side of the frame 30. The non-movable member 45 is supported so as to be slidable. A sliding member (for example, a PTFE (polytetrafluoroethylene) film or a PTFE plate) 46 having a lower friction coefficient than the carriage 22 and the guide plate 45 is fixed to the lower surface of the carriage 22 on the other end 28 side. is there. As a result, when the carriage 22 moves, the sliding member 46 of the carriage 22 comes into sliding contact with the guide plate 45, and fluctuations in sliding resistance (sliding resistance variation) acting when the carriage 22 moves are suppressed. Can do. Further, an elastic member (slidingly contacting the transparent plate 27 in a compressed state) is formed on the upper portion on the other end portion 28 side of the carriage 22 (the planar shape is a quadrangular shape, a cubic or thick plate-like low repulsion). 47 (foam elastic member such as urethane) is fixed by adhesion, double-sided tape or the like. Thereby, the carriage 22 is pressed against the guide plate 45 by the elastic force F generated by the elastic member 47 being elastically deformed. The other end portion 28 of the carriage 22 is fixed with a sliding contact portion between the elastic member 47 and the transparent plate 27 and the carriage 22 (sliding member 46) when the carriage 22 moves in the sub-scanning direction. In this case, frictional resistance is generated at the sliding contact portion between the sliding member 46) and the guide plate 45, and the frictional force in the direction in which the other end 28 side of the carriage 22 is delayed from the one end 23 side of the carriage 22 and this frictional force. Rotation moment M (clockwise rotation moment M in FIG. 2) caused by the above action always acts, preventing the carriage 22 from swinging and stabilizing the posture of the carriage 22. If there is no problem in the sliding state of the carriage 22 and the guide plate 45, the sliding member 46 may be omitted and the carriage 22 and the guide plate 45 may be brought into direct contact. In addition, the shape of the elastic member 47 is not limited to the above-described cubic or thick plate shape, and an elastic force that urges the carriage 22 toward the guide plate 45 is generated, so that the elastic member 47 can smoothly come into sliding contact with the transparent plate 27. If it is.

  According to the image reading apparatus 2 of the first example as described above, the carriage 22 slides while being sandwiched between the transparent plate 27 that is a non-movable member and the guide plate 45 that is a non-movable member. become. Thereby, in the image reading apparatus 2 of the first example, the frictional force acting on the sliding contact portion between the elastic member 47 fixed to the carriage 22 and the transparent plate 27 and the sliding contact portion between the carriage 22 and the guide plate 45 is reduced. It always acts in a direction that prevents the carriage 22 from moving in the sub-scanning direction. As a result, according to the image reading apparatus 2 of the first example, the carriage 22 does not oscillate even if vibration or sliding resistance variation occurs when the carriage 22 moves, and the carriage 22 is stable in posture. To do. Therefore, the image reading apparatus 2 of the first example can accurately read the image of the document G.

  Further, the image reading apparatus 2 of the first example can prevent the carriage 22 from swinging only by sliding the elastic member 47 fixed to the carriage 22 in a state of being elastically deformed to the transparent plate 27. The device structure is not complicated and the product price is not increased.

  In addition, the image reading apparatus 2 of the first example exhibits a function of holding the posture of the carriage 22 by the elastic member 47 fixed to the carriage 22 and also exhibits a vibration and shock absorbing function. There is no problem of deteriorating the image reading function.

  In addition, the image forming apparatus 1 including the image reading apparatus 2 of the first example allows the printer unit 3 to perform high-precision printing on the recording material S based on the accurately read image data.

  As shown in FIG. 1, the image reading apparatus 2 of the first example is provided with an automatic document feeder (ADF) 48 so that the document is automatically supplied to the flow reading position on the transparent plate 27. Also good. In this case, the carriage 22 moves from the home position to the flow reading position, and stops at the flow reading position to read the image.

  The image reading apparatus 2 of the first example is an aspect in which the elastic member 47 is disposed between the carriage 22 and the transparent plate 27, but is not limited thereto, and is elastic on both the upper surface side and the lower surface side of the carriage 22. The member 47 may be fixed, and one of these elastic members 47 may be brought into sliding contact with the transparent plate 27 in a compressed state, and the other elastic member 47 may be brought into sliding contact with the guide plate 45 in a compressed state.

  The image reading apparatus 2 of the first example is an aspect in which the elastic member 47 is disposed between the carriage 22 and the transparent plate 27, but is not limited thereto, and the elastic member 47 is fixed to the lower surface side of the carriage 22. The elastic member 47 may be brought into sliding contact with the guide plate 45 in a compressed state, the sliding member 46 may be fixed to the upper surface side of the carriage 22, and the sliding member 46 may be brought into sliding contact with the transparent plate 27. .

(Second example of image reading apparatus)
FIG. 8 is a diagram schematically illustrating a second example of the image reading apparatus 2. In the image reading apparatus 2 according to the second example, the same components as those of the image reading apparatus 2 according to the first example shown in FIG. A duplicate description is omitted.

  The image reading apparatus 2 shown in FIG. 8 uses a cantilever-like plate spring (elastic member) 50 instead of the elastic member 47 in the first example. In the leaf spring 50, the base portion 51 is fixed to the upper portion on the other end side of the carriage 22, and the distal end side of the spring action portion 52 that rises obliquely in a cantilever shape from the base portion 51 comes into contact with the transparent plate 27. ing. The leaf spring 50 is in contact with the transparent plate 27 in a state in which the spring acting portion 52 is bent and deformed, and the carriage 22 is elastically generated by being bent and deformed between the carriage 22 and the transparent plate 27. Is pressed against the guide plate 45 side.

  Further, the leaf spring 50 is formed in a smooth curved surface shape in which the distal end side of the spring acting portion 52 that contacts the transparent plate 27 is convex upward, and when the carriage 22 moves along the sub-scanning direction, the transparent plate 27 is smoothly slidable and the transparent plate 27 is hardly damaged. In addition, the leaf | plate spring 50 is formed with the resin material or the metal material (for example, spring steel). The plate spring 50 made of a metal material forms a resin film such as PTFE on at least the tip side that is in sliding contact with the transparent plate 27 to reduce wear and the like at the sliding contact portion of the transparent plate 27 with the plate spring 50. It is preferable to plan.

  The image reading apparatus 2 according to the second example having such a configuration can obtain the same effects as the image reading apparatus 2 of the first example.

(Third example of image reading apparatus)
FIG. 9 is a diagram schematically illustrating a third example of the image reading apparatus 2. The image reading apparatus 2 according to the third example is different from the image reading apparatus 2 of the first example only in the structure on the other end 28 side of the carriage 22 and in the vicinity thereof, but other basic components are the first. Since it is the same as the image reading apparatus 2 of one example, the description overlapping with the first example will be omitted, and the characteristic part will be described in detail.

  In the third example of the image reading apparatus 2 shown in FIG. 9, a moving guide portion 53 is formed on the other end portion 28 side of the carriage 22, has a substantially U-shaped cross section that engages with the moving guide portion 53, and in the sub-scanning direction. A guide rail (a second guide member and non-movable member) 54 extending along the frame 30 is fixed to the frame body 30.

  The moving guide portion 53 of the carriage 22 has a sliding member 46 fixed to the lower surface 53 a side, an elastic member 47 fixed to the upper surface 53 b side, and the sliding member 46 is slid from below by the lower piece 54 a of the guide rail 54. The elastic member 47 is slidably accommodated in a compressed state between the elastic member 47 and the upper piece 54 b of the guide rail 54. The sliding member 46 can be omitted when the moving guide portion 53 can smoothly come into sliding contact with the lower piece 54 a of the guide rail 54. Then, the moving guide portion 53 may be brought into direct sliding contact with the lower piece 54 a of the guide rail 54.

  In the image reading apparatus 2 according to the third example having such a configuration, the carriage 22 is moved by the elastic force generated by the elastic member 47 being elastically deformed between the moving guide portion 53 and the upper piece 54b of the guide rail 54. The guide portion 53 is pressed against the lower piece 54 a of the guide rail 54. As a result, when the carriage 22 moves in the sub-scanning direction, the sliding contact portion between the elastic member 47 fixed to the movement guide portion 53 of the carriage 22 and the upper piece 54b of the guide rail 54 and the movement guide portion 53 ( Alternatively, the frictional force acting on the sliding contact portion between the sliding member 46) and the lower piece 54a of the guide rail 54 always acts in a direction that prevents the carriage 22 from moving in the sub-scanning direction. As a result, according to the image reading apparatus 2 of the third example, the carriage 22 is not swung even if vibration or sliding resistance variation occurs when the carriage 22 is moved, and the posture of the carriage 22 is stable. To do. Therefore, the image reading apparatus 2 of the third example can accurately read the image of the original G. Therefore, the image reading device 2 according to the third example can obtain the same effects as the image reading device 2 according to the first example.

  Note that the image reading apparatus 2 of the third example is an aspect in which the elastic member 47 is disposed between the movement guide portion 53 of the carriage 22 and the upper piece 54b of the guide rail 54. The elastic member 47 is fixed to both the lower surface 53a side and the upper surface 53b side of the moving guide portion 53, and the elastic member 47 on the upper surface 53b side of the moving guide portion 53 is brought into sliding contact with the upper piece 54b of the guide rail 54 in a compressed state. The elastic member 47 on the lower surface 53a side of the moving guide portion 53 may be brought into sliding contact with the lower piece 54a of the guide rail 54 in a compressed state.

  The image reading apparatus 2 of the third example is an aspect in which the elastic member 47 is disposed between the movement guide portion 53 of the carriage 22 and the upper piece 54b of the guide rail 54. However, the present invention is not limited to this. The elastic member 47 is fixed to the lower surface 53 a side of the moving guide portion 53, and the elastic member 47 on the lower surface 53 a side of the moving guide portion 53 is brought into sliding contact with the lower piece 54 a of the guide rail 54 in a compressed state. The upper surface 53 b may be brought into sliding contact with the upper piece 54 b of the guide rail 54 directly or via the sliding member 46.

  Further, the image reading device 2 of the third example may apply the leaf spring 50 of the second example instead of the elastic member 47.

(Other variations)
In the image reading apparatus 2 according to the present invention, the optical unit 30 accommodated in the carriage 22 is not limited to the CCD system of the first to second examples, but may be a CIS system.

  In the image reading apparatus 2 according to the present invention, the arrangement and number of the light source 31, the mirror 32, the lens 33, and the CCD 34 of the optical unit 30 accommodated in the carriage 22 are limited to the first and second examples. However, it may be changed as appropriate according to design conditions and the like.

  In the image reading apparatus 2 according to the present invention, the optical unit 30 accommodated in the carriage 22 is not limited to the first and second examples, and can accurately read the image of the document G. As long as possible, the light source 31 and the mirror 32 may be accommodated in the carriage 22, and the lens 33 and the CCD 34 may be disposed outside the carriage 22 and inside the frame body 27.

  The image reading device 2 according to the present invention may be used as a scanner connected to an external device (for example, a computer).

  Further, in the image reading apparatus 2 according to the present invention, the guide rail 24 may be a polygonal bar-like member such as a square bar or a plate-like member. However, the guide rail engaging portion (35) needs to be engaged with the guide rail 24 so as to be slidable so that the carriage 22 can be smoothly moved along the guide rail 24.

1 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention. It is a top view which shows typically the 1st example of an image reading apparatus. FIG. 3 is a structural diagram schematically showing a carriage cut along its moving direction. FIG. 3 is a perspective view showing the carriage as viewed obliquely from above with the transparent plate and the like of the image reading device removed. FIG. 5 is a perspective view of one end side of the carriage viewed from the direction of arrow A in FIG. 4. It is a top view of the one end part side of a carriage. FIG. 5 is a perspective view of the other end portion side of the carriage showing a transparent plate (non-movable member) partially broken, and is a perspective view seen from the direction of arrow B in FIG. 4. FIG. 4 is a structural diagram of a carriage schematically showing a second example of the image reading apparatus, and corresponds to FIG. 3. It is a figure which shows the 3rd example of an image reading apparatus, and is a structure figure of the other end part side of the carriage which shows an image reading apparatus cut | disconnecting along a main scanning direction. It is a top view which shows the conventional image reading apparatus typically. FIG. 11 is a diagram illustrating an image reading apparatus according to a first conventional example, in which FIG. 11A is a front view illustrating a main part of the image reading apparatus, and FIG. 11B is a bottom view illustrating a main part of the image reading apparatus. FIG. It is a figure which shows the image reading apparatus which concerns on a 2nd prior art example. FIG. 13A is a diagram showing an image reading apparatus according to a third conventional example, and FIG. 13A is a diagram showing a state of the image reading apparatus before document scanning, and FIG. 13B is a document scanning of the image reading apparatus. It is a figure which shows the state of.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 2 ... Image reading apparatus, 10 ... Printing means, 22 ... Carriage, 23 ... One end part, 24 ... Guide rail (1st guide member), 25 ... Driving belt , 27... Transparent plate (non-movable member), 28 .. other end, 31... Optical unit, 37, 38 .. pulley, 45... Guide plate (second guide member, non-movable member) 46. ... Sliding member 47... Elastic member 50 .. leaf spring (elastic member) 54... Guide rail (second guide member and non-movable member) 54 a. Lower part 54 b upper part G ... Original, S ... Recording material

Claims (7)

The carriage containing the optical unit for image reading is moved in the sub-scanning direction orthogonal to the main scanning direction of the document placed on the transparent plate by a driving belt stretched around a plurality of pulleys.
In an image reading apparatus in which an image of a document placed on the transparent plate is read via the optical unit in the carriage,
One end of the carriage in the main scanning direction is slidably engaged with a first guide member extending along the sub-scanning direction, and is fixed to the driving belt.
The other end side of the carriage in the main scanning direction is elastically sandwiched between a pair of non-movable members positioned so as to be opposed to each other in the vertical direction, and is guided by the pair of non-movable members. It slides along the sub-scanning direction,
One of the pair of non-movable members is the transparent plate,
The other of the pair of non-movable members is a second guide member that extends along the sub-scanning direction and supports the other end portion side of the carriage so as to be slidable from below.
An elastic member that is in contact with the transparent plate in a compressed state is fixed to a portion facing the transparent plate on the other end side of the carriage,
A portion of the carriage facing the second guide member on the other end side is pressed against and contacted with the second guide member by the elastic force of the elastic member .
When the carriage moving in the sub-scanning direction is viewed in plan, the operation of rotating the carriage in both forward and reverse directions is referred to as a swinging operation.
When the carriage moves in the sub-scanning direction, the sliding contact portion between the elastic member and the transparent plate and the sliding contact portion between the other end side of the carriage and the second guide member include A frictional force that acts in a direction that delays the other end side of the carriage from the one end side of the carriage and that prevents the carriage from swinging is applied. ing,
An image reading apparatus. The carriage containing the optical unit for image reading is moved in the sub-scanning direction orthogonal to the main scanning direction of the document placed on the transparent plate by a driving belt stretched around a plurality of pulleys.
In an image reading apparatus in which an image of a document placed on the transparent plate is read via the optical unit in the carriage,
One end of the carriage in the main scanning direction is slidably engaged with a first guide member extending along the sub-scanning direction, and is fixed to the driving belt.
The other end side of the carriage in the main scanning direction is elastically sandwiched between a pair of non-movable members positioned so as to be opposed to each other in the vertical direction, and is guided by the pair of non-movable members. It slides along the sub-scanning direction,
One of the pair of non-movable members is the transparent plate,
The other of the pair of non-movable members is a second guide member that extends along the sub-scanning direction and supports the other end portion side of the carriage so as to be slidable from below.
A first elastic member that is in contact with the transparent plate in a compressed state is fixed to a portion facing the transparent plate on the other end side of the carriage,
A second elastic member that contacts the second guide member in a compressed state is fixed to a portion of the carriage opposite to the second guide member on the other end side.
When the carriage moving in the sub-scanning direction is viewed in plan, the operation of rotating the carriage in both forward and reverse directions is referred to as a swinging operation.
When the carriage moves in the sub-scanning direction, the sliding contact portion between the first elastic member and the transparent plate and the sliding contact portion between the second elastic member and the second guide member include: A frictional force acting in a direction that delays the other end side of the carriage from the one end side of the carriage, and a frictional force that prevents the carriage from swinging. Has become,
An image reading apparatus. The carriage containing the optical unit for image reading is moved in the sub-scanning direction orthogonal to the main scanning direction of the document placed on the transparent plate by a driving belt stretched around a plurality of pulleys.
In an image reading apparatus in which an image of a document placed on the transparent plate is read via the optical unit in the carriage,
One end of the carriage in the main scanning direction is slidably engaged with a first guide member extending along the sub-scanning direction, and is fixed to the driving belt.
The other end side of the carriage in the main scanning direction is elastically sandwiched between a pair of non-movable members positioned so as to be opposed to each other in the vertical direction, and is guided by the pair of non-movable members. It slides along the sub-scanning direction,
One of the pair of non-movable members is the transparent plate,
The other of the pair of non-movable members is a second guide member that extends along the sub-scanning direction and supports the other end portion side of the carriage so as to be slidable from below.
An elastic member that is in contact with the second guide member in a compressed state is fixed to a portion facing the second guide member on the other end side of the carriage.
The portion opposed to the transparent plate of the other end of the carriage, the elastic member slide member slidably contacts the pressed against and the transparent plate by the elastic force of the transparent plate is fixed ,
When the carriage moving in the sub-scanning direction is viewed in plan, the operation of rotating the carriage in both forward and reverse directions is referred to as a swinging operation.
During the movement of the carriage in the sub-scanning direction, the sliding contact portion between the elastic member and the second guide member and the sliding contact portion between the sliding member and the transparent plate are arranged on the other side of the carriage. A frictional force acting in a direction in which the end side is delayed from the one end side of the carriage, and a frictional force that prevents the carriage from swinging is acting.
An image reading apparatus. The carriage containing the optical unit for image reading is moved in the sub-scanning direction orthogonal to the main scanning direction of the document placed on the transparent plate by a driving belt stretched around a plurality of pulleys.
In an image reading apparatus in which an image of a document placed on the transparent plate is read via the optical unit in the carriage,
One end of the carriage in the main scanning direction is slidably engaged with a first guide member extending along the sub-scanning direction, and is fixed to the driving belt.
The other end side of the carriage in the main scanning direction is elastically sandwiched between a pair of non-movable members positioned so as to be opposed to each other in the vertical direction, and is guided by the pair of non-movable members. It slides along the sub-scanning direction,
One of the pair of non-movable members is an upper piece of a second guide member that extends along the transparent plate and along the sub-scanning direction,
The other of the pair of non-movable members is a lower piece of a second guide member extending along the transparent plate and along the sub-scanning direction,
An elastic member that is in contact with the upper piece in a compressed state is fixed to a portion facing the upper piece on the other end side of the carriage,
The portion of the carriage facing the lower piece on the other end side is pressed against and contacted with the lower piece by the elastic force of the elastic member ,
When the carriage moving in the sub-scanning direction is viewed in plan, the operation of rotating the carriage in both forward and reverse directions is referred to as a swinging operation.
When the carriage moves in the sub-scanning direction, the sliding contact portion between the elastic member and the upper piece of the second guide member, the other end portion side of the carriage, and the second guide member The sliding contact portion with the lower piece has a frictional force acting in a direction in which the other end portion side of the carriage is delayed from the one end portion side of the carriage, and the occurrence of the swing motion of the carriage occurs. Frictional force to prevent
An image reading apparatus. The carriage containing the optical unit for image reading is moved in the sub-scanning direction orthogonal to the main scanning direction of the document placed on the transparent plate by a driving belt stretched around a plurality of pulleys.
In an image reading apparatus in which an image of a document placed on the transparent plate is read via the optical unit in the carriage,
One end of the carriage in the main scanning direction is slidably engaged with a first guide member extending along the sub-scanning direction, and is fixed to the driving belt.
The other end side of the carriage in the main scanning direction is elastically sandwiched between a pair of non-movable members positioned so as to be opposed to each other in the vertical direction, and is guided by the pair of non-movable members. It slides along the sub-scanning direction,
One of the pair of non-movable members is an upper piece of a second guide member that extends along the transparent plate and along the sub-scanning direction,
The other of the pair of non-movable members is a lower piece of a second guide member extending along the transparent plate and along the sub-scanning direction,
A first elastic member that is in contact with the upper piece in a compressed state is fixed to a portion facing the upper piece on the other end side of the carriage,
A second elastic member that is in contact with the lower piece in a compressed state is fixed to a portion facing the lower piece on the other end side of the carriage ,
When the carriage moving in the sub-scanning direction is viewed in plan, the operation of rotating the carriage in both forward and reverse directions is referred to as a swinging operation.
When the carriage moves in the sub-scanning direction, the sliding contact portion between the first elastic member and the upper piece of the second guide member, and the second elastic member and the second guide member The sliding contact portion with the lower piece has a frictional force acting in a direction in which the other end portion side of the carriage is delayed from the one end portion side of the carriage, and the occurrence of the swing motion of the carriage occurs. Frictional force to prevent
An image reading apparatus. The carriage containing the optical unit for image reading is moved in the sub-scanning direction orthogonal to the main scanning direction of the document placed on the transparent plate by a driving belt stretched around a plurality of pulleys.
In an image reading apparatus in which an image of a document placed on the transparent plate is read via the optical unit in the carriage,
One end of the carriage in the main scanning direction is slidably engaged with a first guide member extending along the sub-scanning direction, and is fixed to the driving belt.
The other end side of the carriage in the main scanning direction is elastically sandwiched between a pair of non-movable members positioned so as to be opposed to each other in the vertical direction, and is guided by the pair of non-movable members. It slides along the sub-scanning direction,
One of the pair of non-movable members is an upper piece of a second guide member that extends along the transparent plate and along the sub-scanning direction,
The other of the pair of non-movable members is a lower piece of a second guide member extending along the transparent plate and along the sub-scanning direction,
An elastic member that is in contact with the lower piece in a compressed state is fixed to a portion facing the lower piece on the other end side of the carriage,
The portion facing the upper piece on the other end side of the carriage is pressed against the upper piece by the elastic force of the elastic member ,
When the carriage moving in the sub-scanning direction is viewed in plan, the operation of rotating the carriage in both forward and reverse directions is referred to as a swinging operation.
When the carriage moves in the sub-scanning direction, the sliding contact portion between the elastic member and the lower piece of the second guide member, the other end portion side of the carriage, and the second guide member The sliding contact portion with the upper piece has a frictional force acting in a direction in which the other end portion side of the carriage is delayed more than the one end portion side of the carriage, and the occurrence of the swinging motion of the carriage occurs. Frictional force to prevent
An image reading apparatus. The image reading apparatus according to any one of claims 1 to 6, an image forming apparatus comprising: the printing means for printing on a recording medium based on image data read by the image reading device.

Images