JP2021168441A - Image reading device, and image forming apparatus including the image reading device - Google Patents

Abstract

To prevent excessive increase of a curvature radius of a flexible flat cable (hereinafter referred to as FFC) in a scanner housing in association with movement of a carriage.SOLUTION: An image reading device 2 comprises a cable winding member 51 around which an FFC 24 is wound. The cable winding member 51 has a first winding target part 54a around which a carriage-side cable part 24a is wound, a second winding target part 53a around which a substrate-side cable part 24b is wound, a storage space 53e that is formed inside both the winding target parts 53a, 54a and stretches over both the winding target parts 53a, 54a in a rotation axis direction, a drawing hole 53f of the carriage-side cable part 24a, and a drawing hole 54d of the substrate-side cable part 24b. The cable winding member 51 is urged by urging force from an urging member 52 in a direction to wind the carriage-side cable part 24a around the first winding target part 54a.SELECTED DRAWING: Figure 6

Description

The present invention relates to an image reader and an image forming apparatus including the image reader.

Conventionally, an image reading device including a housing in which a contact glass is attached to an upper surface and a carriage housed in the housing and moving in a predetermined direction along the lower surface of the contact glass has been known. In this image reading device, light is emitted from a light source mounted on a carriage toward a document on a contact glass, and image data of the document is generated based on the reflected light. The carriage is connected to a control board provided in the housing via a flexible flat cable. The flexible flat cable transmits power and signals between the carriage and the control board. A flexible flat cable is usually housed in a housing in a U-shaped curve, with one end connected to the carriage and the other end fixed to the bottom wall of the housing.

In this type of image reader, the radius of curvature of the flexible flat cable increases more than necessary as the carriage moves, which hinders the movement of the carriage or causes harmful static electricity to come into contact with the flexible flat cable and the contact glass. It is known that various problems such as occurrence occur. In order to solve this problem, for example, in the image reading device shown in Patent Document 1, a mountain fold portion is formed in the vicinity of the fixed portion of the flexible flat cable.

Japanese Unexamined Patent Publication No. 2011-30032

However, even if the flexible flat cable is provided with a mountain fold portion as in the conventional image reading device shown in Patent Document 1, it is not possible to completely eliminate the increase or decrease in the radius of the curved portion of the flexible flat cable due to the movement of the carriage. .. Therefore, for example, when the rigidity of the flexible flat cable changes due to aged deterioration or the like, the radius of the curved portion of the flexible flat cable may be excessively increased and the above-mentioned various problems may occur.

The present invention has been made in view of this point, and an object of the present invention is to prevent the bending radius of the flexible flat cable in the scanner housing from being excessively increased with the movement of the carriage.

The image reading device according to one aspect of the present invention is equipped with a scanner housing having a contact glass on the upper surface and a light source that irradiates light toward a document on the contact glass, and is mounted in the scanner housing in the main scanning direction. A carriage that reciprocates in the orthogonal sub-scanning direction, an electronic board that is arranged outside the scanner housing, and an electronic board that is arranged so as to penetrate the wall portion of the scanner housing, one end of which is connected to the carriage and the other end. A flexible flat cable whose portion is connected to the electronic board, and a cable winding member that is rotatably provided around the rotation axis extending in the main scanning direction in the scanner housing and around which the flexible flat cable is wound. And an urging member that urges the cable winding member around the rotation axis, and the flexible flat cable is connected to the carriage side cable portion on the side connected to the carriage and the electronic board. The cable winding member includes a board-side cable portion on the side of a cable, an intermediate cable portion that connects the carriage-side cable portion and the substrate-side cable portion in a state of being displaced in the rotation axis direction, and the cable winding member is the carriage. The first wound portion around which the side cable portion is wound, the second wound portion coaxially fixed to the first wound portion and the substrate side cable portion is wound, and the first wound portion. And inside the second wound portion, the accommodation space formed across the both wound portions and accommodating the intermediate cable portion, and the first wound portion formed in the intermediate cable. A pull-out hole for pulling out the carriage-side cable portion connected to the portion from the accommodation space to the outside in the radial direction of the first wound portion, and the second wound portion formed in the intermediate cable portion. It has a pull-out hole for pulling out the connected substrate-side cable portion outward in the radial direction of the second wound portion, and the carriage-side cable portion is pulled by the urging force from the urging member. It is configured to be urged in the direction of winding around the first wound wound portion.
The image forming apparatus according to another aspect of the present invention includes the image reading apparatus.

According to the present invention, it is possible to prevent the radius of curvature of the flexible flat cable in the scanner housing from being excessively increased as the carriage moves.

FIG. 1 is a schematic view showing an internal structure of an image forming apparatus including the image reading apparatus according to the embodiment. FIG. 2 is a schematic view showing the internal structure of the image reading device and the internal structure of the portion of the image forming device main body in which the control substrate is housed. FIG. 3 is a cross-sectional view taken along the line III-III of FIG. 2, which is an enlarged view of the rear end portion of the image reading device. FIG. 4 is a schematic view showing a state in which the flexible flat cable is bent so as to be divided into a carriage side cable portion and a substrate side cable portion. FIG. 5 is a view taken along the V direction of FIG. FIG. 6 is a sectional view taken along line VI-VI of FIG. FIG. 7 is a side view of the first bobbin as viewed from the outside in the radial direction. FIG. 8 is a view taken along the line VIII of FIG. FIG. 9 is a side view of the second bobbin as viewed from the outside in the radial direction. FIG. 10 is an arrow view in the X direction of FIG. FIG. 11 is a side view of the partition plate as viewed from the outside in the radial direction. FIG. 12 is an arrow view in the XII direction of FIG. FIG. 13 is a diagram corresponding to FIG. 2 showing the second embodiment. FIG. 14 is a side view of the tension roller mounted on the cable portion on the substrate side as viewed from the outside in the radial direction. FIG. 15 is an arrow view in the XV direction of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following embodiments.

<< Embodiment 1 >>
FIG. 1 shows an image forming apparatus A on which the image reading apparatus 2 of the embodiment is mounted. The image forming apparatus A has an image forming apparatus main body 1 and the image reading apparatus 2 fixed on the upper side of the image forming apparatus main body 1. The image forming apparatus A forms an image on a sheet based on the image data read by the image reading apparatus 2 or the image data input from an information processing apparatus such as an external personal computer. In the following description, unless otherwise specified, the front side and the rear side mean the front side and the rear side of the image forming apparatus A, and the left side and the right side are the left side and the right side when the image forming apparatus A is viewed from the front side. Means.

[Structure of image forming apparatus main body 1]
The image forming apparatus main body 1 has a rectangular box-shaped housing 4. The housing 4 internally houses a paper feed cassette 5 that houses a bundle of sheets, an image forming section 6 that forms a toner image on the sheet, and a fixing section 7 that fixes the toner image on the sheet. A discharge tray 8 for discharging the sheet after image formation is provided on the left side surface of the housing 4.

The image forming unit 6 has a photoconductor drum 61 as an image carrier that supports a toner image. A charging device 62, a developing device 63, a transfer roller 64, and a static elimination device 65 are arranged in this order in the clockwise direction around the photoconductor drum 61 with reference to the 12 o'clock position. On the right side of the developing device 63, a toner container for storing toner and supplying toner to the developing device 63 is provided.

The fixing portion 7 has a fixing roller 71 and a pressure roller 72 that face each other vertically with the sheet transport path interposed therebetween. The fixing roller 71 is heated by a heater (not shown) housed inside the fixing roller 71.

In the image forming process of the sheet, first, the surface of the photoconductor drum 61 is uniformly charged to a predetermined potential by the charging device 62. Next, a laser scanner unit (LSU) (not shown) irradiates the surface of the photoconductor drum 61 with light based on image data. As a result, an electrostatic latent image is formed on the surface of the photoconductor drum 61. Then, the electrostatic latent image on the photoconductor drum 61 is developed as a toner image by the developing device 63. Subsequently, the toner image formed on the photoconductor drum 61 is transferred to the sheet by a transfer bias having the opposite polarity to the toner charged on the transfer roller 64. The potential on the surface of the photoconductor drum 61 after transfer is statically eliminated by the static elimination device 65. The toner image transferred to the sheet by passing through the transfer roller 64 is heated and pressurized when the sheet passes between the fixing roller 71 and the pressure roller 72, and melt-fixed to the sheet.

[Structure of image reader 2]
The image reading device 2 optically reads the image of the document P to be read and generates the image data. Specifically, as shown in FIGS. 1 and 2, the image reading device 2 includes a scanner housing 21, a contact glass 22, a carriage 23, and a flexible flat cable (hereinafter referred to as FFC) 24. There is.

The scanner housing 21 is formed in a flat rectangular parallelepiped shape and is fixed to the upper surface of the image forming apparatus main body 1 with bolts or the like. The contact glass 22 is attached to the upper surface of the scanner housing 21. The contact glass 22 has a first glass portion 22A used in the sheet-through method described later and a second glass portion 22B used in the sheet fixing method.

As shown in FIG. 3, the carriage 23 has a carriage main body 23a and a protruding plate 23b protruding rearward from the rear end surface of the carriage main body 23a. The carriage body 23a includes a light source that emits light toward the document on the contact glass 22 and a contact image sensor (hereinafter referred to as a CIS sensor) that generates an image signal by photoelectric conversion based on the reflected light from the document. Is installed. A carriage-side connector 81 to which one end of the FFC 24 is connected is attached to the projecting plate 23b. The carriage-side connector 81 is arranged so that its insertion port faces the left side, and one end of the FFC 24 is inserted from the left side with respect to the carriage-side connector 82. The other end of the FFC 24 is connected to the board-side connector 82 as shown in FIG. The board-side connector 82 is arranged on the left side of the control board 100 housed in the upper end of the image forming apparatus main body 1. The board-side connector 82 is connected to the control board 100 via the wiring 101. The board-side connector 82 is arranged so that its insertion port faces the left side. The other end of the FFC 24 is inserted from the left side with respect to the board side connector 82.

The carriage 23 is supported by a rail 25 (shown only in FIGS. 1 and 2) fixed to the bottom wall portion 21a of the scanner housing 21 via a slider 26. The rail 25 extends over the entire bottom wall portion 21a of the scanner housing 21 in the left-right direction. The slider 26 is arranged so as to be slidable in the left-right direction by engaging with the rail 25.
Then, the carriage 23 is located in the left-right direction (mainly) along the rail 25 between the predetermined home position (solid line position in FIG. 2) and the predetermined movement end position (two-dot chain line position in FIG. 2). It is possible to reciprocate in the sub-scanning direction (secondary scanning direction orthogonal to the scanning direction). The carriage 23 is located directly below the first glass portion 22A at the home position, and is located directly below the right edge of the second glass portion 22B at the moving end position.

There are a sheet-through method and a sheet fixing method as a method of reading a document image by the image reading device 2. In the sheet-through method, the carriage 23 is kept stationary at the home position, and the sheet is supplied onto the first glass portion 22A by the document automatic feeding device 30 described later to pass through a predetermined document reading position R. On the other hand, in the sheet fixing method, the document P is fixed on the upper surface of the contact glass 22, and the carriage 23 is reciprocated in the sub-scanning direction (left-right direction in FIG. 2).

[Automatic document feeder 30]
The automatic document feeding device 30 is rotatably supported at the rear end of the scanner housing 21 via a pair of hinge mechanisms. The document automatic feed device 30 supplies a sheet to the document reading position R when scanning an image by the sheet-through method.

Specifically, as shown in FIG. 1, the automatic document feeder 30 includes a document paper feed tray 31, a document output tray 32 provided under the document paper feed tray 31, and the document paper feed tray 31. It has a U-shaped document transport path 33 extending from 31 to the document output tray 32. When scanning an image by the sheet-through method, the automatic document feeding device 30 moves the document P set in the document feeding tray 31 downstream one by one by a plurality of transport rollers 34 arranged along the document transport path 33. After passing through the document reading position R set on the contact glass 22, it is ejected to the document ejection tray 32. In the sheet-through method, the carriage 23 is stationary at the home position below the document reading position R, and the reflected light from the document P passing through the document reading position R is captured by the CIS sensor mounted on the carriage 23. Is done. The CIS sensor photoelectrically converts the reflected light to generate an image signal, and transmits the generated image signal to the control board 100 (an example of an electronic board) in the image forming apparatus main body 1 via the FFC 24.

On the other hand, at the time of reading by the sheet fixing method, the document automatic feeding device 30 is rotated upward with the hinge mechanism at the rear end as a fulcrum to be positioned at the open position. Then, the sheet is set on the upper surface of the contact glass 22, and then the automatic document feeder 30 is returned to the closed position to fix the sheet on the upper surface of the contact glass 22. In this state, the carriage 23 is moved in the left-right direction (sub-scanning direction) to irradiate the entire document surface with light, so that the reflected light is taken into the CIS sensor. The CIS sensor photoelectrically converts the reflected light from the captured original image to generate an image signal, and transmits the generated image signal to the control board 100 via the FFC 24.

As shown in FIG. 2, the FFC 24 transmits the image signal, the drive signal of the carriage 23, electric power, and the like between the carriage 23 and the control board 100. The FFC 24 is an elastically deformable ribbon-shaped wiring in which conductors made of rectangular tin-plated copper foil are arranged at regular intervals in the width direction and sandwiched between two thin insulating films. The FFC 24 has a feature that it can maintain its electrical characteristics even when it is deformed. Both ends of the FFC 24 are reinforced with a thick PET film called a reinforcing plate so that they can be connected to the connectors 81 and 82.

As shown in FIGS. 4 and 5, the FFC 24 has a cable winding member 51 (FIG. 6 and the like) of the loosening prevention device 50 described later in a state of having a carriage side cable portion 24a, a substrate side cable portion 24b, and an intermediate cable portion 24c. See). The carriage-side cable portion 24a is a portion of the FFC 24 that is connected to the carriage 23, and the substrate-side cable portion 24b is a portion that is connected to the control board 100. The intermediate cable portion 24c connects the carriage side cable portion 24a and the substrate side cable portion 24b in a state of being shifted in the cable width direction (the direction of the rotation axis of the cable winding member 51 described later and the left-right direction in FIG. 4). It is the part to do. As shown in FIG. 5, for example, the intermediate cable portion 24c is formed so as to fold the intermediate portion in the longitudinal direction of the FFC 24. The FFC 24 is bifurcated into a carriage-side cable portion 24a and a substrate-side cable portion 24b via an intermediate cable portion 24c. The FFC 24 is fixed with an adhesive tape or the like so as to maintain this bifurcated shape.

[Detailed configuration of slack prevention device 50]
As shown in FIGS. 2 and 3, a slack prevention device 50 for preventing the FFC 24 from slackening due to the movement of the carriage 23 is provided in the scanner housing 21.

As shown in FIG. 6, the slack prevention device 50 includes a cable winding member 51 and a mainspring 52 (an example of an urging member). The cable winding member 51 is arranged between the front support wall 27 and the rear support wall 28 erected on the bottom wall portion 21a of the scanner housing 21. The cable winding member 51 is rotatably supported at both ends around the axis by a support pin 27a projecting from the front support wall 27 and a support pin 28a projecting from the rear support wall 28. By urging the cable winding member 51 around its axis, the mainspring 52 always urges the portion of the FFC 24 between the cable winding member 51 and the carriage 23 in the winding direction. The axes of the support pin 27a and the support pin 28a form the rotation axis of the cable winding member 51.

[Detailed configuration of cable winding member 51]
The configuration of the cable winding member 51 will be described in more detail with reference to FIGS. 6 to 11.
As shown in FIG. 6, the cable winding member 51 has a first bobbin 53, a second bobbin 54, and a partition plate 55.

As shown in FIGS. 6 to 8, the first bobbin 53 is configured by arranging a drum portion 53a, a flange portion 53b, a protruding shaft portion 53c, and a supported portion 53d coaxially with each other.

The drum portion 53a has a cylindrical shape, and the substrate-side cable portion 24b is wound around the outer peripheral surface of the drum portion 53a. The outer diameter of the drum portion 53a is set smaller (for example, 1/2 or less) than the outer diameter of the drum portion 54a of the second bobbin 54, which will be described later. The drum portion 53a corresponds to the second wound winding portion.

The flange portion 53b has a disc shape that protrudes radially outward from the rear end portion of the drum portion 53a in a flange shape. A rod-shaped protrusion 53g is projected from the peripheral edge of the rear side surface of the flange portion 53b. The protruding shaft portion 53c is connected to the front end surface of the drum portion 53a with a step, and is formed in a D-shaped cross section.

The supported portion 53d is a cylindrical portion connected to the rear side surface of the flange portion 53b. A support pin 28a projecting from the rear support wall 28 is fitted on the inner surface of the supported portion 53d. As shown in FIG. 6, a cylindrical hole 53e is formed inside the first bobbin 53 coaxially with its rotation axis. The cylindrical hole 53e corresponds to a storage space for accommodating the intermediate cable portion 24c of the FFC 24.

The cylindrical hole 53e is formed over the entire area from the drum portion 53a of the first bobbin 53 to the protruding shaft portion 53c in the front-rear direction, and the front end thereof is open. A support pin 27a projecting from the front support wall 27 is fitted into the opening at the front end of the cylindrical hole 53e.

The drum portion 53a and the protruding shaft portion 53c of the first bobbin 53 are further formed with slit holes 53f extending in the entire front-rear direction. The slit hole 53f communicates with the cylindrical hole 53e from the outside in the radial direction. The portion of the slit hole 53f corresponding to the drum portion 53a corresponds to a drawer hole for pulling out the substrate-side cable portion 24b from the inside of the cylindrical hole 53e.

As shown in FIG. 6, the second bobbin 54 is externally fitted and supported on the protruding shaft portion 53c of the first bobbin 53. The second bobbin 54 is arranged on the side opposite to the drum portion 53a side of the first bobbin 53 with the partition plate 55 interposed therebetween.

Specifically, the second bobbin 54 has a drum portion 54a and a flange portion 54b, as shown in FIGS. 6, 9 and 10. The drum portion 54a has a cylindrical shape, and a carriage-side cable portion 24a is wound around the outer peripheral surface of the drum portion 54a. The drum portion 54a corresponds to the first wound winding portion. A slit hole 54d extending in the front-rear direction is formed in the drum portion 54a. The slit hole 54d is formed at the same phase position as the slit hole 53f formed in the first bobbin 53 when viewed from the axial direction. That is, as shown in FIG. 6, the slit hole 54d of the drum portion 54a and the slit hole 53f formed in the first bobbin 53 are located in the same cross section including the rotation axis of the cable winding member 51. .. The carriage-side cable portion 24a is pulled out radially outward of the drum portion 54a via the slit hole 53f of the first bobbin 53 and the slit hole 53f of the drum portion 54a of the second bobbin 54. In this way, the slit hole 53f of the first bobbin 53 and the slit hole 54d of the second bobbin 54 form a drawer hole for pulling out the carriage side cable portion 24a from the inside of the cylindrical hole 53e.

The flange portion 54b of the second bobbin 54 is connected to the front end surface of the drum portion 54a. The outer diameter of the flange portion 54b is larger than the outer diameter of the drum portion 54a. A D-shaped fitting hole 54c is formed in the center of the flange portion 54b, and the protruding shaft portion 53c of the first bobbin 53 fits into the fitting hole 54c and penetrates the fitting hole 54c. A ring-shaped stopper 56 is provided on the front side of the flange portion 54b. The stopper 56 is mounted in a ring groove 53h (see FIG. 7) formed at the front end of the protruding shaft portion 53c of the first bobbin 53. The stopper 56 regulates the position of the second bobbin 54 so that the second bobbin 54 does not fall off from the front end of the protruding shaft portion 53c.

As shown in FIG. 6, the partition plate 55 is externally fitted and supported on the protruding shaft portion 53c of the first bobbin 53. The partition plate 55 is arranged so as to partition the drum portion 53a of the first bobbin 53 and the drum portion 54a of the second bobbin 54 in the front-rear direction.

Specifically, as shown in FIGS. 6, 10 and 11, the partition plate 55 is composed of a disk-shaped member having a substantially D-shaped fitting hole 55a formed in the central portion. The partition plate 55 is arranged so that the fitting hole 55a is fitted onto the protruding shaft portion 53c of the first bobbin 53. The rear side surface of the partition plate 55 is in contact with the stepped surface 53i located at the boundary between the drum portion 53a of the first bobbin 53 and the protruding shaft portion 53c. An annular rib 55b is provided on the front surface of the partition plate 55 coaxially with the fitting hole 55a. The outer peripheral surface of the annular rib 55b is fitted to the inner peripheral surface of the drum portion 54a of the second bobbin 54.

Further, as shown in FIG. 12, the partition plate 55 is formed with a slit-shaped cut portion 55d extending radially outward from the fitting hole 55a in the central portion. The partition plate 55 is configured to be twistably deformable (elastically deformable) by displacing one side and the other side in the opposite directions in the thickness direction with the cut portion 55d interposed therebetween. In the present embodiment, the partition plate 55 is formed of a resin member that is prone to such torsional deformation. Therefore, by twisting and deforming the partition plate 55 during the assembly work of the cable winding member 51, the interval between the cut portions 55d can be widened, and the FFC 24 can be easily inserted into the cut portion 55d.

[Summary of the procedure for assembling the slack prevention device 50]
When assembling the slack prevention device 50, first, using an adhesive tape or the like, the FFC 24 is fixed in a bifurcated shape including a carriage side cable portion 24a, a substrate side cable portion 24b, and an intermediate cable portion 24c as shown in FIG. do.

Then, the FFC 24 fixed in a bifurcated shape is set so that the intermediate cable portion 24c fits in the cylindrical hole 53e of the first bobbin 53 (see FIGS. 7 and 8). At this time, the carriage-side cable portion 24a and the substrate-side cable portion 24b of the FFC 24 are inserted into the slit hole 53f of the first bobbin 53 and pulled out radially outward.

In this state, the partition plate 55 (see FIGS. 11 and 12) is fitted and attached to the protruding shaft portion 53c of the first bobbin 53 from the front side. At this time, by twisting and deforming the partition plate 55 as described above to widen the interval between the cut portions 55d, the carriage-side cable portion 24a easily passes through the cut portion 55d. When the mounting of the partition plate 55 is completed, the board-side cable portion 24b is located on the rear side of the partition plate 55, and the carriage-side cable portion 24a is located on the front side of the partition plate 55.

In this state, the second bobbin 54 (see FIGS. 9 and 10) is fitted onto the protruding shaft portion 53c of the first bobbin 53 from the front side. At this time, the carriage side cable portion 24 is inserted into the slit hole 54d of the second bobbin 54. After the mounting of the second bobbin 54 is completed, the stopper 56 is mounted in the ring groove 53h of the first bobbin 53, so that the first bobbin 53, the second bobbin 54, and the partition plate 55 are connected to the cable winding member 51 (FIG. 6) is unitized.

Then, in the unitized cable winding member 51, the carriage side cable portion 24a is wound around the drum portion 54a of the second bobbin 54, and the substrate side cable portion 24b is wound around the drum portion 53a of the first bobbin 53. turn.

Then, as shown in FIG. 6, after the cable winding member 51 is rotatably supported by the support pin 27a of the front support wall 27 and the support pin 28a of the rear support wall 28, the carriage 23 is set to the home position. By moving, one end of the mainspring 52 is fixed to the protrusion 53g of the first bobbin 53, and the other end of the mainspring 52 is fixed to the protrusion 28b of the rear support wall 28. The mainspring 52 is attached to the cable winding member 51 so as not to generate an urging force when the carriage 23 is in the home position. In this way, the assembly of the slack prevention device 50 is completed.

After the assembly of the slack prevention device 50 is completed, with the carriage 23 in the home position, the tip of the carriage side cable portion 24a is connected to the carriage side connector 81 (see FIG. 2), and the tip of the board side cable portion 24b is connected to the substrate. Connect to the side connector 82.

As shown in FIG. 2, the winding direction M of the carriage side cable portion 24a and the substrate side cable portion 24b with respect to the cable winding member 51 is the counterclockwise direction in FIG. The urging direction U is the clockwise direction in FIG.

[Explanation of operation of slack prevention device 50]
The operation of the slack prevention device 50 configured as described above will be described with reference to FIGS. 2 and 3 and the like. In FIGS. 2 and 3, the state of the FFC 24 when the carriage 23 is in the home position is shown by a solid line, and the state of the FFC 24 when the carriage 23 is in the moving end position is shown by a chain double-dashed line.

First, when the carriage 23 is in the home position, the carriage-side cable portion 24a is arranged horizontally from the cable winding member 51 toward the carriage-side connector 81 without slack, and the substrate-side cable portion 24b is the cable winding member 51. It is arranged diagonally downward to the right toward the board side connector 82 without slack.

When the carriage 23 is moved from the home position to the terminal position (that is, when it is moved to the right side), the tip of the carriage side cable portion 24a moves to the right side together with the carriage 23 (see the alternate long and short dash line in FIG. 2). ). Along with this, the cable winding member 51 rotates in the counterclockwise direction of FIG. 2, and the carriage-side cable portion 24a is unwound from the drum portion 54a (see FIG. 3) of the cable winding member 51. At this time, since the cable winding member 51 is urged by the spring 52 in the clockwise direction of FIG. 2 (that is, the direction in which the carriage side cable portion 24 is wound), the carriage side cable portion 24a does not loosen. .. Further, when the carriage 23 is moved from the moving end position to the home position (when moving to the left side), the carriage side cable portion 24a is wound by the cable winding member 51 at a speed higher than the moving speed of the carriage 23. Therefore, even in this case, the carriage side cable portion 24 does not loosen. Therefore, various problems caused by the excessive increase in the radius of curvature of the FFC 24 in the scanner housing 21, for example, the problem of hindering the movement of the carriage 23 and the problem of generating static electricity due to the rubbing between the FFC 24 and the contact glass 22. Can be avoided.

On the other hand, the board-side cable portion 24b is fed out from the drum portion 53a of the cable winding member 51 as the carriage 23 moves to the terminal position, like the carriage-side cable portion 24a. Is fixed to the board side connector 82 and does not move. Therefore, the substrate-side cable portion 24b eventually loosens in a U-shape that is convex downward as shown by the alternate long and short dash line in FIG. However, the slackening of the cable portion 24b on the substrate side occurs in the image forming apparatus main body 1 outside the scanner housing 21, and does not occur in the scanner housing 21. Therefore, the above-mentioned problem does not occur due to the increase in the radius of curvature of the FFC 24 in the scanner housing 21.

Moreover, the outer diameter of the drum portion 53a of the first bobbin 53 around which the substrate-side cable portion 24b is wound is smaller than the outer diameter of the drum portion 54a of the second bobbin 54 around which the carriage-side cable portion 24a is wound. Therefore, when the carriage 23 moves from the home position to the terminal position (when moving to the right side), the length of the board-side cable portion 24b drawn out from the drum portion 53a of the first bobbin 53 can be made as small as possible. can. Therefore, the amount of slack in the substrate-side cable portion 24b due to the movement of the carriage 23 is suppressed as much as possible, and the accommodation space of the substrate-side cable portion 24b in the image forming apparatus main body 1 is reduced to improve space efficiency. be able to.

Further, in the present embodiment, the urging member for urging the cable winding member 51 is composed of the mainspring 52. One end of the mainspring 52 is fixed to the scanner housing 21 via the rear support wall 28, and the other end is fixed to the cable winding member 51. According to this configuration, the cable winding member 51 can be urged in the winding direction of the carriage side cable portion 24a due to the compact configuration.

<< Embodiment 2 >>
FIG. 13 is a diagram corresponding to FIG. 2 showing the second embodiment. In this embodiment, the configuration of the urging member for urging the cable winding member 51 around the rotation axis is different from that in the first embodiment. In the following description, the same components as those in FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted.
That is, in the present embodiment, the mainspring 52 in the first embodiment is abolished, and the tension roller 57 is used as the urging member.

As shown in FIG. 13, the tension roller 57 is attached to the upper surface of the substrate-side cable portion 24b in the image forming apparatus main body 1. The tension roller 57 is only held by the retaining member 58 on the upper surface of the substrate-side cable portion 24b, and is not supported by other support members. The tension roller 57 is supported on the upper surface of the substrate-side cable portion 24b and can be displaced in the vertical direction following a change in the amount of slack in the substrate-side cable portion 24b. Therefore, the board-side cable portion 24b is always pulled downward by the weight of the tension roller 57 to give tension. The cable winding member 51 is constantly urged around the rotation axis by the tension applied through the substrate-side cable portion 24b.

As shown in FIGS. 14 and 15, the tension roller 57 has a columnar rotor body 57a and a pair of derailment prevention guides 57b. The pair of derailment prevention guides 57b project radially outward from both ends in the width direction on the outer peripheral surface of the rotor body 57a. The outer peripheral surfaces of the pair of derailment prevention guides 57b are formed in a tapered surface shape in which the diameter becomes smaller toward the inside in the width direction of the rotor main body 57a. A through hole 57c (see FIG. 15) penetrating in the axial direction is formed in the central portion of the tension roller 57. Both ends of the retaining member 58 formed by bending the wire into a C shape are inserted and held in the through hole 57c. The board-side cable portion 24b is inserted between the retaining member 58 and the outer peripheral surface of the tension roller 57. By providing such a retaining member 58, the tension roller 57 mounted on the upper surface of the cable portion 24b on the substrate side is prevented from falling off.

When the tension roller 57 configured as described above is applied as it is to the configuration of the first embodiment (configuration of FIG. 2), when the carriage 23 moves to the right side, the cable winding member 51 tensions from the tension roller 57. Is urged in the counterclockwise direction of FIG. As a result, rather than applying tension to the carriage-side cable portion 24a, the occurrence of slack is promoted.

Therefore, in the second embodiment, the winding direction Mc of the carriage side cable portion 24a with respect to the cable winding member 51 (drum portion 54a) and the winding of the substrate side cable portion 24b with respect to the cable winding member 51 (drum portion 53a). The directions Ms are set to be opposite to each other.

That is, in the example of FIG. 13, the winding direction Mc of the carriage side cable portion 24a with respect to the cable winding member 51 is the counterclockwise direction in the figure, whereas the winding direction Mc of the substrate side cable portion 24b with respect to the cable winding member 51 is The turning direction Ms is the clockwise direction in the figure.

By adopting such a winding method, the cable winding member 51 is urged in the clockwise direction (U direction in FIG. 13) by the tension from the tension roller 57. That is, the cable winding member 51 is urged by the tension from the tension roller 57 in the direction of winding the carriage side cable portion 24a. Therefore, it is possible to prevent the carriage side cable portion 24a from being excessively curved (slackened) in the scanner housing 21 as the carriage 23 moves. Therefore, by adopting the configuration of the present embodiment, the same effect as that of the first embodiment can be obtained.

<< Other Embodiments >>
In the second embodiment, the tension roller 57 is configured to apply tension to the substrate-side cable portion 24b by its own weight, but the present invention is not limited to this. For example, the tension roller 57 may be supported by a support member such as a slider that can move in the vertical direction, and the slider may be urged downward by an urging spring to apply tension to the cable portion 24b on the substrate side. good.

In the first and second embodiments, the other end of the FFC 24 is connected to the control board 100 via the board side connector 82 and the wiring 101, but the present invention is not limited to this, and the other end of the FFC 24 is not limited to this. It may be directly connected to the control board 100.

In the first and second embodiments, an example in which the image forming apparatus A on which the image reading apparatus 2 is mounted is a printer has been described, but the present invention is not limited to this. The image forming apparatus A may be a facsimile, a copying machine, a multifunction device (MFP), or the like.

The present invention also includes a configuration in which the first and second embodiments are combined.

As described above, the present invention is useful for image readers, and is particularly useful when applied to facsimiles, copiers, multifunction devices (MFPs), and the like.

A: Image forming apparatus P: Original 1: Image forming apparatus main body 2: Image reading device 21: Scanner housing 22: Contact glass 23: Carriage 24: Carrying side cable part 24a: Carrying side cable part 24b: Board side cable part 24c : Intermediate cable part 51: Cable winding member 52: Scanner spring (biasing member)
53a: Drum part (second winding part)
53e: Cylindrical hole (accommodation space)
53f: Slit hole (drawer hole)
54a: Drum part (first wound part)
54d: Slit hole (drawer hole)
57: Tension roller (biasing member)
100: Control board (electronic board)

Claims (5)

A scanner housing with contact glass on the top surface and
A carriage that is equipped with a light source that irradiates light toward the document on the contact glass and moves back and forth in the sub-scanning direction orthogonal to the main scanning direction in the scanner housing.
An electronic board arranged outside the scanner housing and
A flexible flat cable arranged so as to penetrate the wall portion of the scanner housing, one end connected to the carriage and the other end connected to the electronic substrate.
A cable winding member that is rotatably provided around a rotation axis extending in the main scanning direction in the scanner housing and around which the flexible flat cable is wound.
A urging member that urges the cable winding member around the rotation axis is provided.
The flexible flat cable rotates the carriage-side cable portion on the side connected to the carriage, the substrate-side cable portion on the side connected to the electronic board, the carriage-side cable portion, and the substrate-side cable portion. It has an intermediate cable part that connects in a state shifted in the axial direction, and has.
The cable winding member is fixed coaxially with the first wound portion around which the carriage-side cable portion is wound and the first wound portion, and the substrate-side cable portion is wound around the second. A winding portion, a storage space formed inside the first and second winding portions straddling both winding portions and accommodating the intermediate cable portion, and the first winding portion. A lead-out hole for pulling out the carriage-side cable portion formed in the rotation portion and connected to the intermediate cable portion from the accommodation space to the outside in the radial direction of the first winding portion, and the second winding portion. It has a pull-out hole for pulling out the substrate-side cable portion connected to the intermediate cable portion to the outside in the radial direction of the second wound portion, and has an urging force from the urging member. An image reading device configured to urge the carriage-side cable portion in a direction of winding around the first wound portion. In the image reading apparatus according to claim 1,
An image reading device in which the outer diameter of the second wound portion around which the substrate-side cable portion is wound is smaller than the outer diameter of the first wound portion around which the carriage-side cable portion is wound. In the image reading device according to claim 1 or 2.
The urging member is an image reading device including a mainspring having one end fixed to the scanner housing and the other end fixed to the cable winding member. In the image reading device according to claim 1 or 2.
The winding direction of the carriage-side cable portion with respect to the first wound portion and the winding direction of the substrate-side cable portion with respect to the second wound portion are opposite to each other.
The urging member is formed of a tension roller that is supported on the upper surface of the substrate-side cable portion and can be displaced in the vertical direction according to a change in the amount of slack in the substrate-side cable portion. The tension transmitted to the second wound portion via the side cable portion urges the cable winding member in the direction of winding the carriage side cable portion around the first wound portion. An image reader that is configured. The image reading device according to any one of claims 1 to 4.
The image reader is provided with an image forming apparatus main body mounted on the upper end surface.
The electronic substrate is an image forming apparatus housed in the image forming apparatus main body.

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