Sheet supply device, and image forming device

Abstract

To prevent falling of a cover member from a manual feeding tray.SOLUTION: A manual paper feeding device 70 includes: a manual feeding tray 72 on which a sheet supplied to an image forming device body 2 is placed; a dust prevention cover 90 which slides and is mounted with respect to the manual feeding tray 72 and covers a sheet placement surface 72B of the manual feeding tray 72; and a right cover 71 mounted on the image forming device body 2 and holding the manual feeding tray 72. The device further includes a pulling spring 77 which connects the dust prevention cover 90 and the right cover 71 and energizes the dust prevention cover 90 in a direction of being mounted on the manual feeding tray 72.SELECTED DRAWING: Figure 17

Description

[Technical Field]

[0001] The present invention relates to a sheet feeding device and an image forming apparatus. [Background technology]

[0002] 2. Description of the Related Art There is an invention in which a dust cover (cover member) is attached to a manual feed tray provided in an image forming apparatus to cover the paper placement surface of the tray (for example, Patent Document 1).

[0003] The dust cover may fall off the manual feed tray if a force is applied to it in the removal direction, which is the opposite direction to the attachment direction. For example, an operator may come into contact with the dust cover and unintentionally apply force in this direction, or if the dust cover is attached to an opening / closing cover (opening / closing member) of the image forming device, opening the opening / closing cover may press the dust cover in the removal direction. Summary of the Invention [Problem to be solved by the invention]

[0004] The object is to prevent a cover member from falling off from a manual feed tray. [Means for solving the problem]

[0005] In order to solve the above problems, the present invention provides a sheet feeding device comprising a manual feed tray on which sheets to be supplied to the device main body are placed, a cover member that slides onto the manual feed tray and covers the sheet placement surface of the manual feed tray, and a holding member that is attached to the device main body and holds the manual feed tray, and is characterized in that it comprises a biasing member that connects the cover member and the holding member and biases the cover member in the direction of being attached to the manual feed tray. [Effects of the Invention]

[0006] The cover member can be prevented from falling off the manual feed tray. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram illustrating the configuration of an image forming apparatus. [Figure 2] 1 is a perspective view of a manual paper feeder according to an embodiment of the present invention; [Figure 3] FIG. 2 is a side view of the image forming apparatus showing the right cover and the manual feed tray in a closed state. [Figure 4] FIG. 2 is a side view of the image forming apparatus showing the right cover and the manual feed tray, with the right cover in an open state and the manual feed tray in a closed state. [Figure 5] FIG. 2 is a side view of the image forming apparatus showing the right cover and the manual feed tray, with the right cover in a closed state and the manual feed tray in an open state. [Figure 6] FIG. 2 is a side view of the image forming apparatus showing the right cover and the manual feed tray in an open state. [Figure 7] FIG. 4 is a perspective view showing one widthwise side of the right cover. [Figure 8] FIG. 2 is a perspective view showing one width direction side of the manual feed tray. [Figure 9] FIG. 2 is an exploded perspective view showing a base portion and a cover portion that constitute the dustproof cover. [Figure 10] FIG. 2 is a perspective view of the dustproof cover with the cover portion closed. [Figure 11] FIG. 4 is a side view of the dustproof cover with the cover portion open. [Figure 12] 1A and 1B are diagrams showing the structure for maintaining the posture of the cover, in which FIG. 1A shows the cover in a closed state, and FIG. 1B shows the cover in an open state. [Figure 13] FIG. 10 is a side view of the manual feed tray before the dustproof cover is attached. [Figure 14] FIG. 10 is a side view of the manual feed tray with the dustproof cover attached thereto. [Figure 15] FIG. 10 is a perspective view of the manual feed tray with the dustproof cover attached thereto. [Figure 16]10A to 10C are side cross-sectional views illustrating how the dustproof cover falls off the manual feed tray when the right cover is opened in a manual feed device different from the present embodiment. [Figure 17] FIG. 2 is a side view showing a biasing member provided in the manual paper feeder according to the first embodiment of the present invention. [Figure 18] 5(a) and 5(b) are side cross-sectional views showing the operation of opening and closing the right cover in the manual paper feeder according to the first embodiment of the present invention. [Figure 19] 10 is a side view showing another example of a biasing member provided in the manual paper feeder. FIG. [Figure 20] FIG. 10 is a perspective view showing a sliding portion of the dustproof cover relative to the manual feed tray. [Figure 21] FIG. 10 is a perspective view showing a sliding portion of the manual feed tray relative to the dustproof cover. [Figure 22] 5A and 5B are schematic diagrams illustrating restricting portions provided on the manual feed tray and the dustproof cover. [Figure 23] 23 is a side cross-sectional view showing the manual paper feeder having the regulating unit of FIG. 22 with the right cover open. FIG. [Figure 24] 4 is a schematic diagram showing a low-friction member provided on the dustproof cover. FIG. [Figure 25] FIG. 4 is a perspective view showing a roller member provided on the dustproof cover. [Figure 26] 10 is a schematic view showing a roller member provided on the dustproof cover. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each drawing, the same or corresponding parts are designated by the same reference numerals, and redundant explanations will be appropriately simplified or omitted.

[0009] 1, a copying machine 1 serving as an image forming apparatus includes an image forming apparatus main body 2, an image reading device 3, a paper feeder 4, an automatic document feeder 5, a switchback device 42, and a manual document feeder 70 serving as a sheet supply device. The image reading device 3 is disposed on top of the image forming apparatus main body 2. The automatic document feeder 5 is disposed on top of the image reading device 3 so as to be able to open and close freely.

[0010] The image forming apparatus main body 2 is equipped therein with a drum-shaped photoconductor 10 as an image carrier. A charging device 11 is arranged around the photoconductor 10 on the left side in the drawing, and a developing device 12, a transfer device 13, and a cleaning device 14 are arranged along the rotation direction of the photoconductor 10 (counterclockwise: arrow A in the drawing). The transfer device 13 is configured by wrapping a transfer belt 17 around upper and lower rollers 15 and 16, and is configured to press the transfer belt 17 against the circumferential surface of the photoconductor 10 at transfer position B.

[0011] To the left of the charging device 11 and cleaning device 14, there is disposed a toner supply device 20 that supplies new toner to the developing device 12. Also disposed inside the image forming apparatus main body 2 is a sheet transport device 19 that feeds sheets such as paper and overhead projector sheets from a supply position (to be described later), transports them to a stack position via a transfer position 18, and includes a supply path R1, a manual feed path R2, and a sheet transport path R (to be described later). The sheet transport path R is generally L-shaped, extending from bottom to top in the drawing, passing between the photoconductor 10 and the transfer device 13, and then curving to the left.

[0012] In addition, a registration roller 21 is disposed in the sheet conveying path R at a position upstream of the photoreceptor 10. Furthermore, a fixing device 22 is disposed in a position downstream of the photoreceptor 10. The fixing device 22 includes a pair of fixing rollers (fixing roller rotators) 31, 32. A fixing heater is disposed inside one of the fixing rollers 31, and a pressure spring and a pressure arm are disposed around the other fixing roller 32. The pressure spring and the pressure arm press the one fixing roller 31 against the other fixing roller 32. Furthermore, a thermistor and a thermostat are disposed in one fixing roller 31.

[0013] The fixing heater measures the temperature of the fixing roller 31 using a thermistor, and the fixing heater is turned on or off using a thermostat, thereby maintaining one of the fixing rollers 31 at a predetermined temperature.

[0014] Further downstream of the fixing device 22, there are arranged a discharge branch claw 34, a discharge roller 35, a first pressure roller 36, a second pressure roller 37, and a stiffening roller 38, and downstream in the sheet conveying direction there is arranged a discharge stack section (discharge position) 39 for stacking sheets on which images have been formed.

[0015] A laser writing device 47 is disposed on the left side of the developing device 12 in the drawing. The laser writing device 47 includes a laser light source, a rotating polygon mirror 48 for scanning, a polygon motor 49, and a scanning optical system 50 including an fθ lens.

[0016] The image reading device 3 includes a light source 53, a plurality of mirrors 54, an imaging optical lens 55, an image sensor 56 such as a CCD, and the like, and has a contact glass 57 disposed on the top surface.

[0017] One end of the automatic document feeder 5 is connected to one end of the upper surface of the image reading device 3 by a connector with a hinge structure. The automatic document feeder 5 is provided so that it can be freely opened and closed so that its lower surface can be tilted at an angle of, for example, up to 90 degrees from a horizontal state in which the document paper placed on the upper surface of the contact glass 57 is pressed from above to an open state in which the angle with respect to the upper surface of the contact glass 57 is at most 90 degrees. The automatic document feeder 5 is equipped with a loading tray at the document loading position and a discharge tray at the discharge position, as well as a sheet transport device having a document transport path that transports sheets such as documents from the loading tray to the reading position on the contact glass 57 of the image reading device 3 and then to the discharge tray. The sheet transport device is equipped with a plurality of sheet transport rollers (sheet transport rotating bodies) that transport sheets such as documents.

[0018] The paper feeder 4 is internally provided with multiple stages of paper separation devices 61, which are supply positions for sheets S. Each paper separation device 61 is provided with a pickup roller (feed roller) 62, a feed roller (feed roller) 63, and a reverse roller (separation roller) 64. On the right side of the multiple staged paper separation devices 61 in the drawing, a supply path R1 is formed which leads to a sheet conveying path R of the image forming apparatus main body 2. The supply path R1 is provided with several sheet conveying rollers (sheet conveying rotors) 66 which convey the sheets.

[0019] The switchback device 42 is disposed on the right side of the image forming apparatus main body 2 in the drawing. The switchback device 42 includes a sheet transport device 23 that branches off from the sheet transport path R at the position of the discharge branch claw 34. The sheet transport device 23 includes a reversing path R3 that leads to a switchback position 44 where a pair of switchback rollers 43 are disposed, and a re-transport path R4 that leads from the switchback position 44 back to the registration rollers 21 of the sheet transport path R. The sheet transport device 23 also includes a plurality of sheet transport rollers (sheet transport rotating bodies) 66 that transport sheets. In this embodiment, the switchback device 42 is configured to be attached to a right cover 71, which will be described later.

[0020] The manual paper feeder 70 is disposed on the right side of the image forming apparatus main body 2 in the drawing. The manual paper feeder 70 includes a pickup roller (feed roller) 67A, a feed roller (feed roller) 67B, and a reverse roller (feed roller) 67C, and supplies sheets S loaded on a manual feed tray 72 to a sheet transport path R of the image forming apparatus main body 2.

[0021] Next, we will explain the operation of copier 1. First, to copy an image onto an original using copier 1, the main switch is turned on and the original is set in automatic document feeder 5. Alternatively, automatic document feeder 5 can be opened and the original can be set directly on contact glass 57 of image reading device 3, and automatic document feeder 5 can be closed to hold the original down.

[0022] When the start switch is pressed, if an original is set on the automatic original feeder 5, the original is moved by the sheet feed rollers through the original feed path onto the contact glass 57, and then the image reading device 3 is driven, the contents of the original are read, and the original is discharged onto the discharge tray. On the other hand, if an original is set directly on the contact glass 57, the image reading device 3 is immediately driven.

[0023] When the image reading device 3 starts to operate, the light source 53 emits light while moving along the contact glass 57, irradiating the document surface on the contact glass 57 with the light. The multiple mirrors 54 receive the light reflected from the document surface and reflect it toward the imaging optical lens 55. The imaging optical lens 55 forms an image of this reflected light on the image sensor 56. In this way, the image sensor 56 reads the contents of the document.

[0024] At the same time, the photoreceptor 10 is rotated by the photoreceptor drive motor, and as a result, the surface of the photoreceptor is uniformly charged by the charging device 11, which uses a charging roller. Next, the laser writing device 47 writes on the surface of the photoreceptor by irradiating the surface of the photoreceptor with laser light in accordance with the content of the original document read by the image reading device 3. This forms an electrostatic latent image on the surface of the photoreceptor 10. Thereafter, when the electrostatic latent image portion formed on the surface of the photoreceptor corresponds to the developing device 12, toner is attracted to the surface of the photoreceptor, and the electrostatic latent image is made visible.

[0025] Furthermore, when the start switch is pressed, a corresponding paper separation device 61 is selected from the multiple paper separation devices 61 arranged in multiple stages in the paper feeder 4 based on a paper size selection signal. Then, a pickup roller 62 corresponding to this paper separation device 61 feeds one sheet S from this paper separation device 61. When multiple sheets S are about to be fed, a reverse roller 64 separates the uppermost sheet S and prevents the remaining sheets S from being conveyed. Next, a feed roller 63 feeds the sheet S to supply path R1. A sheet conveying roller 66 conveys the fed sheet S to sheet conveying path R, and a registration roller 21 abuts against the sheet S and stops the conveyance of the sheet S. Then, this registration roller 21 rotates in synchronization with the rotation of the photosensitive member 10 described above, and feeds the sheet S to the right side of the photosensitive member 10.

[0026] When manual paper feed is performed, the manual feed tray 72 of the manual feeder 70 transitions from a closed, upright position to an open, tilted position as shown in FIG. 1. This connects the sheet transport path provided in the manual feed tray 72 to the sheet transport path in the device body. In this state, a sheet is placed on the sheet placement surface 72B of the manual feed tray 72. When the start switch is pressed, the pickup roller 67A feeds one sheet, and the feed roller 67B then takes over. When multiple sheets are being fed, the reverse roller 67C separates the topmost sheet and prevents the remaining sheets from being conveyed. The sheet conveying roller 66 continues to convey the sheet fed into the manual feed path R2 and guides it to the sheet conveying path R. Thereafter, similar to the paper feeder 4 described above, the registration roller 21 feeds the sheet to the right side of the photoconductor 10 in synchronization with the rotation of the photoconductor 10.

[0027] Next, when sheet S, which has been sent to the right side of photoreceptor 10, reaches transfer position B, transfer device 13 transfers the toner image on photoreceptor 10 onto sheet S to form an image. Cleaning device 14 removes and cleans residual toner from photoreceptor 10 after image transfer, and then a discharge device removes residual potential from photoreceptor 10 to prepare for the next image formation starting from charging device 11.

[0028] Next, the fixing device 22 conveys the sheet S onto which the above-mentioned toner image has been transferred by the transfer belt 17, passes it between a pair of fixing rollers 31 and 32, and fixes the transferred image at the fixing position by applying heat and pressure. After the fixing, the sheet S is made flat and stiffened in the process of passing through a first pressure roller 36, a discharge roller 35, a second pressure roller 37, and a stiffening roller 38, and is then discharged onto a discharge stack section 39 and stacked there.

[0029] When an image is to be transferred onto both sides of the sheet S, the discharge branch claw 34 is switched to transport the sheet S, with the image transferred onto its front side, from the sheet transport path R to the reversal path R3. Then, the sheet S is transported to the switchback position 44 by the sheet transport rollers 66, and switches back at the switchback position 44. Thereafter, the sheet S is transported to the re-transport path R4 and reversed, and is transported again to the sheet transport path R by the sheet transport rollers 66. Thereafter, an image is transferred onto the back side of the sheet S in the same manner as described above.

[0030] Next, a more detailed description will be given of the configuration of the manual paper feeder 70. In this embodiment, a manual paper feeder that feeds paper as sheets to an image forming apparatus will be described as an example of a sheet feeder of the present invention.

[0031] Fig. 2 is a perspective view of a manual paper feeder according to one embodiment of the present invention. Figs. 3 to 6 are side views of an image forming apparatus showing the right cover and manual tray of the manual paper feeder, with Fig. 3 showing the right cover and manual tray in a closed state, Fig. 4 showing the right cover with an open state and the manual tray in a closed state, Fig. 5 showing the right cover with an open state and the manual tray in an open state, and Fig. 6 showing the right cover and manual tray in an open state.

[0032] As shown in FIG. 2, the manual feeder 70 includes a right cover 71 and a manual feed tray 72. A dustproof cover is attached to the manual feed tray 72 to cover the sheet placement surface of the manual feed tray 72. The sheet feeder of the present invention includes a holding member for holding the manual feed tray. One form of this holding member is an openable / closable member that is provided so as to be openable and closable relative to the device body. The right cover 71 of this embodiment is a specific example of this openable / closable member. Direction X in FIG. 2 is the width direction of the right cover 71 and the manual feed tray 72, and is also the width direction of the paper placed on the manual feed tray 72. The paper width direction is a direction perpendicular to the thickness direction of the paper and the transport direction. Direction Y is the paper transport direction in the manual feed tray 72. Direction Z is the vertical direction of the manual feeder 70 and the image forming device. However, this direction does not necessarily have to be the direction of gravity or its opposite direction. Directions X, Y, and Z are perpendicular to one another.

[0033] The right cover 71 is provided on the right side of the image forming apparatus 1 (see FIG. 1) and is connected to a side panel of the image forming apparatus 1 via a rotation fulcrum 71A. The right cover 71 is provided rotatably relative to the image forming apparatus main body 2 around the rotation fulcrum 71A. By rotating the right cover 71, the right cover 71 can be switched between a closed state in an upright position (see FIG. 3) and an open state in an inclined position relative to the image forming apparatus main body 2 (see FIG. 4). The rotation fulcrum 71A is provided at the bottom of the right cover 71 when it is in the upright position, and the top of the right cover 71 is opened and closed by rotating the right cover 71 about the rotation axis direction X. An operator can open the right cover 71 by releasing a lever 71C provided in a recess of the right cover 71. With the right cover 71 in the open position, an operator can access the sheet transport path R and the re-transport path R4 (see FIG. 1) within the image forming apparatus 1, enabling jam clearance and maintenance.

[0034] The manual feed tray 72 is connected to the right cover 71 via a first manual feed link 75 and a second manual feed link 76 (see FIG. 13), and is rotatable relative to the right cover 71. This rotation enables the manual feed tray 72 to switch between a closed state in an upright position (see FIG. 3) and an open state in an inclined position relative to the right cover 71 (see FIG. 4). A rotation fulcrum 72A (see FIG. 3) of the manual feed tray 72 is provided at the bottom of the manual feed tray 72 in the upright position, and the manual feed tray 72 rotates relative to the right cover 71 with its rotation axis in the same direction X as the right cover 71. The opening direction of the manual feed tray 72 is the same as the opening direction of the right cover 71, and the manual feed tray 72 rotates in a direction that moves the upper part on the opposite side of the rotation fulcrum away from the image forming apparatus main body.

[0035] 2, stoppers 72C serving as mating protrusions are provided on both side surfaces of manual tray 72. When manual tray 72 is closed, stoppers 72C fit into stopper holes 71B provided in right cover 71. This keeps manual tray 72 closed relative to right cover 71.

[0036] 3, the right cover 71 is connected to the image forming apparatus main body 2 by a first link member 73 and a second link member 74. A rotation fulcrum 73A, which is one end of the first link member 73, is connected to the image forming apparatus main body 2, and the other end 73B of the first link member 73 is connected to one end 74A of a second link member 74. A rotation fulcrum 74B, which is the other end of the second link member 74, is connected to the right cover 71.

[0037] The first link member 73 is provided rotatably about one end 73A, and the second link member 74 is provided rotatably relative to the first link member 73 about one end 74A.

[0038] Manual tray 72 is connected to second link member 74 via flexible linear member 81 and spring member 82. Specifically, one end of linear member 81 is connected to intermediate portion 74C of second link member 74 via a through-hole of through-hole portion 71D (see FIG. 7) provided in right cover 71. A wire, for example, is used as linear member 81. One end of linear member 81 may be connected to first link member 73.

[0039] 4 and other figures, the other end of linear member 81 is connected to spring member 82 via a through-hole of through-hole portion 72D of manual feed tray 72. Spring member 82 is provided to be extendable and contractible, and pulls linear member 81. One end of spring member 82 is connected to linear member 81, and the other end is fixed to manual feed tray 72. As spring member 82, for example, a coil spring can be used.

[0040] Between the other end of linear member 81 and through-hole 72D, pulley 85 abuts against linear member 81, thereby changing the extending direction of linear member 81. In addition, a contact member 83 is attached to linear member 81 at a predetermined position between the other end of linear member 81 and through-hole 72D. The position of contact member 83 changes along the extending direction of linear member 81 due to the expansion and contraction of spring member 82. When contact member 83 abuts against contacted member 84 fixed to manual feed tray 72, further extension of spring member 82 is restricted. As shown in FIG. 8 , linear member 81, through-hole 72D, contact member 83, contacted member 84, and spring member 82 are provided on one widthwise side of manual feed tray 72, and linear member 81 and spring member 82 extend in the sheet conveying direction on manual feed tray 72. These linear member 81, spring member 82, abutting member 83, and abutted member 84 constitute a rotation regulating section 86 that regulates the opening angle of the manual feed tray 72 relative to the right cover 71, i.e., the rotation angle of the manual feed tray 72, to a certain value or less when the right cover 71 is open.

[0041] Next, the opening and closing operations of the right cover 71 and the manual feed tray 72 will be described.

[0042] When the right cover 71 and manual feed tray 72 in Figure 3 are closed relative to the image forming apparatus body in an upright position, the first link member 73 and the second link member 74 are folded and stored, and the linear member 81 is in a relaxed state.

[0043] As shown in Figures 3 and 4, by rotating only the right cover 71 a predetermined amount about the rotation fulcrum 71A and opening it relative to the image forming apparatus main body 2, the first link member 73 and the second link member 74 are opened and stretched. This holds the right cover 71 in the inclined position shown in Figure 4 relative to the image forming apparatus main body 2. Also, the linear member 81 is in a more extended state in Figure 4 than in Figure 3. In Figures 3 and 4, the spring member 82 is in a compressed state. The abutting member 83 is located away from the abutted member 84. In the state shown in Figure 4, an operator can access the sheet transport path and re-transport path inside the image forming apparatus.

[0044] 3 to 5, only the manual feed tray 72 is rotated about the rotation fulcrum 72A to open it relative to the right cover 71. This stretches the linear member 81 and places it under tension. Also, the spring member 82 is contracted, and the abutting member 83 is positioned away from the abutted member 84. The manual feed tray 72 is held in the inclined position shown in FIG. 5 by the first manual feed link 75 (see FIG. 2) and the second manual feed link 76 (see FIG. 13). In this state, a sheet can be placed on the sheet placement surface 72B of the manual feed tray 72 and fed into the image forming apparatus.

[0045] As shown in Figures 4 to 6 or Figures 5 to 6, both right cover 71 and manual tray 72 are opened. As a result, linear member 81 no longer extends from the tensioned state shown in Figure 5, and spring member 82 extends instead of linear member 81. Then, contact member 83 moves toward contacted member 84 and abuts against contacted member 84. This restricts the movement of contact member 83, and prevents spring member 82 from extending any further. In other words, manual tray 72, which is connected to second link member 74 via spring member 82 and linear member 81, can no longer move in a direction away from second link member 74, and manual tray 72 is held in the position shown in Figure 6 relative to second link member 74 and right cover 71.

[0046] As described above, the manual feed tray 72 is connected to the right cover 71 by the first manual feed link and the second manual feed link and can be tilted relative to the right cover 71 to an opening angle α1 as shown in FIG. 5 . However, due to the restriction imposed by the contact member 84 in FIG. 6 , when the right cover 71 is open, the manual feed tray 72 can only be opened to an opening angle α2 (<α1) relative to the right cover 71. This prevents the manual feed tray 72 from tilting downward from the horizontal position even when the right cover 71 is open, thereby preventing sheets placed on the manual feed tray 72 from falling off the manual feed tray 72. Note that the position at which the manual feed tray 72 is held is not limited to horizontal. For example, even if the manual feed tray 72 is tilted downward from the horizontal, the sheet can be prevented from falling if the frictional force between the manual feed tray 72 and the sheet is greater than the force in the direction of the sheet's own weight. The opening angles α1 and α2 shown here are angles on a plane perpendicular to the X direction.

[0047] Incidentally, the manual feed tray 72 of this embodiment is provided with a dustproof cover that covers the sheet placement surface 72B of the manual feed tray 72 and covers the sheets. The configuration of this dustproof cover will be described below with reference to Figures 9 to 11. Note that in Figures 9 to 11, etc., the illustration of a biasing member, which will be described later, is omitted.

[0048] As shown in Fig. 9, a dustproof cover 90 serving as a cover member has a base portion 91 and a cover portion 92. A rotation fulcrum 92A of the cover portion 92 is inserted into a connecting hole 91A of the base portion 91, thereby attaching the cover portion 92 to the base portion 91, as shown in Fig. 10. The cover portion 92 is provided to be rotatable about the rotation fulcrum 92A relative to the base portion 91. Fig. 10 shows the cover portion 92 in a closed state relative to the base portion 91. The rotation axis direction of the cover portion 92 is parallel to direction X.

[0049] The base portion 91 has stopper holes 91B as fitting holes on both sides in the width direction. The base portion 91 has a pair of abutment portions 91C. However, the number of abutment portions 91C may be one or three or more. The cover portion 92 has a handle 92B. The handle 92B is a portion formed with a hole so that an operator can grasp it, for example.

[0050] By grasping and lifting the handle 92B of the cover part 92, the cover part 92 can be rotated around the rotation fulcrum 92A, and the cover part 92 can be opened relative to the base part 91 as shown in Figure 11.

[0051] By attaching the cover 92 to the base 91, as shown in FIG. 12(a), the position-maintaining protrusion 92D of the cover 92 is inserted into the hole 91D of the base 91. FIG. 12(a) illustrates the state in which the cover 92 is closed relative to the base 91, as shown in FIG. 10. By opening the cover 92 from this state relative to the base 91, the position-maintaining protrusion 92D moves along the hole 91D in the direction of the arrow in FIG. 12(a). Then, due to the operator's operating force, the position-maintaining protrusion 92D moves over the slope 91D1 that forms the hole 91D and is positioned in the position shown in FIG. 12(b). In this state, the position-maintaining protrusion 92D abuts against the lower end surface 91D2 due to its own weight, thereby maintaining its position. In other words, the cover 92 is maintained in the open position shown in FIG. 11 relative to the base 91. The end surface 91D2 is the end surface of the base 91 that forms the hole 91D. When closing the cover part 92, the operator applies force in the direction of closing the cover part 92, causing the position-maintaining protrusion 92D to climb over the slope 91D1 and return to the position shown in Figure 12(a). In this way, the position-maintaining protrusion 92D and the hole 91D constitute a position-maintaining part that maintains the open position of the cover part 92 relative to the base part 91.

[0052] Next, how to attach the dustproof cover 90 to the manual feed tray 72 will be described with reference to Figures 13 to 15. Figure 13 is a side view of the dustproof cover 90 before it is attached to the manual feed tray 72, and Figures 14 and 15 are a side view and a perspective view of the dustproof cover 90 after it has been attached.

[0053] As shown in FIG. 13 , the dustproof cover 90 is attached to the manual feed tray 72 by moving it in the direction of arrow B1 relative to the inclined manual feed tray 72. The direction of arrow B1 is also the direction in which the dustproof cover 90 approaches the image forming apparatus main body. Specifically, as shown in FIG. 14 , the manual feed tray 72 is inserted between upper rails 91E and lower rails 91F provided on the base of the dustproof cover 90, and the dustproof cover 90 slides in the direction of arrow B1 relative to the manual feed tray 72. Then, the stopper 72C of the manual feed tray 72 fits into the stopper hole 91B of the base 91, thereby determining the position of the dustproof cover 90 relative to the manual feed tray 72. Furthermore, the abutment portion 91C of the base 91 abuts against the right cover 71, thereby maintaining the orientation of the dustproof cover 90 relative to the right cover 71 as shown in FIG. 14 . In this manner, the dustproof cover 90 is attached to the manual feed tray 72. The sliding direction of the dustproof cover 90, indicated by arrow B1 relative to manual insertion, is the direction in which the dustproof cover 90 is attached to the manual feed tray 72. The opposite direction, indicated by arrow B2, is the direction in which the dustproof cover 90 is removed (or falls off) from the manual feed tray 72. The upper rail 91E and the lower rail 91F are provided on the widthwise end sides (see FIG. 9), and slide against the widthwise end sides of the manual feed tray 72, so they do not come into contact with the paper on the manual feed tray 72. The stopper hole 91B forms a fitting portion that fits the base portion 91 of the dustproof cover 90 to the manual feed tray 72.

[0054] As described above, the dustproof cover 90 is not fixed to the manual feed tray 72 or the right cover 71 by screws or the like, but its posture is maintained by structural positioning such as fitting or abutment. This makes it easy to attach and detach the dustproof cover 90 to and from the manual feed tray 72.

[0055] The base portion 91 of the dustproof cover 90 is a portion that determines the positioning relative to the manual feed tray 72 and the right cover 71. The cover portion 92 is a portion that covers the paper on the manual feed tray 72. By configuring the cover portion 92 to be openable and closable relative to the base portion 91, an operator can access the paper placed on the manual feed tray 72 with the dustproof cover 90 attached to the manual feed tray 72, and can also load paper onto the manual feed tray 72.

[0056] However, in a configuration in which the dustproof cover 90 is not fixed to another member by screws or the like, as in this embodiment, there is a problem that the dustproof cover 90 may fall off the manual feed tray 72. Particularly in a configuration in which the right cover 71 and the manual feed tray 72 rotate in the same direction on the same rotation axis, as in this embodiment, the dustproof cover 90 may be pushed when the right cover 71 is opened, causing the dustproof cover 90 to fall off the manual feed tray 72. Hereinafter, this falling off of the dustproof cover 90 will be explained using a manual feeder 70' different from this embodiment shown in Figures 16(a) to 16(c). The manual feeder 70' has the same configuration as the manual feeder 70 of this embodiment, except that it does not have a biasing member, which will be described later.

[0057] 16(a) and 16(b), when the dustproof cover 90 is attached to the manual feed tray 72 in an inclined position and the right cover 71 is opened in the direction of arrow C for jam clearance or the like, the right cover 71 presses the abutment portion 91C of the dustproof cover 90, and a force is applied to the dustproof cover 90 in the direction of arrow B2, which is the direction in which the dustproof cover 90 is removed from the manual feed tray 72. This disengages the stopper 72C from the stopper hole 91B, and the dustproof cover 90 is no longer positioned relative to the manual feed tray 72. As a result, the dustproof cover 90 moves in the direction of arrow B2, as shown in FIG. 16(c), due to its own weight or due to being pressed by the right cover 71 as the right cover 71 opens further. Then, when the lower rail 91F of the dustproof cover 90 moves to a position separated from the manual feed tray 72, the manual feed tray 72 can no longer support the dustproof cover 90, and the dustproof cover 90 falls off from the manual feed tray 72 (see the direction of arrow B3). The above-described falling off of the dustproof cover 90 does not necessarily occur due to a single action of opening the right cover 71. For example, the first action of opening the right cover 71 may cause the stopper 72C to come out of the stopper hole 91B, and then several subsequent actions of opening and closing the right cover 71 may cause the dustproof cover 90 to gradually move in the direction of falling off, and ultimately fall off.

[0058] In particular, in this embodiment, as shown in FIG. 6 above, the opening angle α2 of the manual feed tray 72 with respect to the right cover 71 is restricted in order to prevent paper from falling out of the manual feed tray 72 when the right cover 71 is opened. In other words, opening the right cover 71 brings the right cover 71 and the manual feed tray 72 closer together. For this reason, the dustproof cover 90 is likely to be pressed by the right cover 71 when the right cover 71 is opened, which can easily cause the above-mentioned problem of the dustproof cover 90 falling out.

[0059] One way to address the problem of dustproof cover 90 falling off is to make the opening and closing directions of right cover 71 and manual feed tray 72 different, thereby preventing dustproof cover 90 from being pushed in the direction that would cause it to fall off when right cover 71 is opened. However, having a rotation axis in two directions leads to problems such as the device becoming more complex and larger, the opening and closing procedures becoming more complicated, and an increase in operational errors.

[0060] The configuration of the manual sheet feeder 70 of this embodiment, which prevents the dust cover 90 from falling off, will be described below with reference to FIG. 17 and FIGS. 18(a) and 18(b).

[0061] 17, a tension spring 77 is provided as a biasing member on the dustproof cover 90 of this embodiment. One end of the tension spring 77 is fixed to the base portion 91, and the other end 77A is connected to the right cover 71.

[0062] The tension spring 77 is attached to the dust cover 90, and after the dust cover 90 is attached to the manual feed tray 72, the other end 77A of the tension spring 77 is connected to the right cover 71. For example, the right cover 71 can be provided with a hook for hooking the other end 77A. The tension spring 77 can be attached to the right cover 71 through a simple attachment method. Alternatively, the other end 77A of the tension spring 77 can be attached to an attachment member such as a bracket, and the attachment member can be fitted into the right cover. Connecting the tension spring 77 to the right cover 71 via an attachment member makes it possible to connect the tension spring 77 to the right cover 71 by fitting, etc., which increases the degree of freedom in the structure for connecting the tension spring 77 and makes installation easier.

[0063] In this embodiment, the tension spring 77 is directly connected to the right cover 71, but the "connection" of the biasing member of the present invention to the manual feed tray or the holding member is not necessarily limited to this. That is, the biasing member may be indirectly connected to the manual feed tray via another member, such as indirectly connected to the manual feed tray via the bracket described above. Also, the right cover 71 may directly hold the manual feed tray 72, or may indirectly hold the manual feed tray via another member. Also, the holding member may be configured to be indirectly attached to the device body via another member.

[0064] In the manual paper feeder 70 of this embodiment, the right cover 71 is opened with the dustproof cover 90 attached to the manual tray 72 as shown in FIG. 16(b). In this case, as in the case of FIG. 16(b), the abutment portion 91C of the dustproof cover 90 is pressed by the right cover 71, and the dustproof cover 90 moves in the direction of removal from the manual tray 72 (the direction of arrow B2). However, in the manual paper feeder 70 of this embodiment, as shown in FIG. 18(a), the dustproof cover 90 is connected to the right cover 71 by the tension spring 77, so that the dustproof cover 90 is held in place by the tension of the tension spring 77, preventing the dustproof cover 90 from falling off the manual tray 72. Specifically, the tension spring 77 is stretched by the amount by which the dustproof cover 90 moves in the removal direction and away from the right cover 71. As a result, a force is applied to the dustproof cover 90 in the direction of arrow B1, which is the direction in which the tension spring 77 contracts, that is, the direction in which the dustproof cover 90 approaches the right cover 71 and attaches the dustproof cover 90 to the manual feed tray 72. Furthermore, by closing the right cover 71, the tension of the tension spring 77 moves the dustproof cover 90 toward the right cover 71, and as shown in FIG. 18(b), the dustproof cover 90 can be returned to a predetermined position, such as the position where it was attached to the manual feed tray 72. The biasing force of the tension spring 77 in the direction of arrow B1 is set to be greater than the sum of the component of the dustproof cover 90's own weight in the direction in which it falls off and the frictional force generated between the dustproof cover 90 and the manual feed tray 72. As a result, the dustproof cover 90 can be held and moved in the direction of arrow B1.

[0065] As described above, in this embodiment, the tension spring 77 prevents the dustproof cover 90 from falling off the manual feed tray 72. Furthermore, by expanding and contracting the tension spring 77, the position of the dustproof cover 90 relative to the right cover 71 is not fixed, and it is also possible to move the dustproof cover 90 in the direction of arrow B2 when the right cover 71 is opened. This prevents damage to the right cover 71 or the dustproof cover 90 that may occur when trying to forcefully open the right cover 71. Furthermore, when removing the dustproof cover 90, the connection of the dustproof cover 90 to the right cover 71 can be released simply by releasing the hook of the tension spring 77 on the right cover 71, making it easy to attach and detach the dustproof cover 90.

[0066] The biasing member provided on dustproof cover 90 is not limited to the above-mentioned tension spring, but may be any member that biases dustproof cover 90 in the attachment direction to manual feed tray 72. For example, in manual paper feeder 70 shown in Figure 19, dustproof cover 90 is provided with expandable rubber member 78 as a biasing member that is connected to right cover 71.

[0067] Next, a modified example of the manual paper feeder 70 will be described.

[0068] Instead of the biasing member provided on the dustproof cover 90 described above, a restricting portion may be provided that restricts movement of the dustproof cover 90 in the removal direction relative to the manual feed tray 72. Specifically, as shown in FIG. 20 , a restricting rib 91G is provided on the inner side surface of the base portion 91. Also, as shown in FIG. 21 , a contact rib 72E is provided on the outer side surface of the manual feed tray 72. As shown in FIG. 22 , the restricting rib 91G is a rib that protrudes toward the manual feed tray 72, and the contact rib 72E is a rib that protrudes toward the base portion 91. When the dustproof cover 90 moves in the direction of arrow B2, which is the removal direction relative to the manual feed tray 72, the restricting rib 91G abuts against the contact rib 72E, restricting further movement of the dustproof cover 90 in the direction of arrow B2. In this way, the restricting rib 91G and the contact rib 72E form a restricting portion 79 that restricts movement of the dustproof cover 90 in the removal direction relative to the manual feed tray 72.

[0069] The restricting rib 91G and the abutting rib 72E are configured with a vertical surface on one side in the attachment / detachment direction of the dustproof cover 90 and an inclined surface on the other side. As a result, when the dustproof cover 90 moves in the removal direction as shown in FIG. 22 , the vertical surfaces of the restricting rib 91G and the abutting rib 72E abut against each other, restricting the movement of the dustproof cover 90. On the other hand, when attaching the dustproof cover 90 to the manual feed tray 72, the restricting rib 91G and the abutting rib 72E are guided by their respective inclined surfaces, causing the manual feed tray 72 to bend upward in FIG. 22 , and the restricting rib 91G clears the abutting rib 72E, allowing the dustproof cover 90 to be attached to the manual feed tray 72. This configuration of the restricting portion 79 restricts the movement of the dustproof cover 90 in the removal direction without the restricting portion 79 interfering with the attachment of the dustproof cover 90 or complicating the attachment operation. However, the base of the dustproof cover 90 may be bent. Furthermore, when removing the dustproof cover 90 from the manual feed tray 72, the operator applies an operating force to cause the restricting rib 91G to climb over the abutting rib 72E, thereby allowing the dustproof cover 90 to be removed. However, the restricting rib 91G and the abutting rib 72E may be configured to retract from the manual feed tray 72 side or the dustproof cover 90 side.

[0070] In this embodiment, as shown in FIG. 23 , when the right cover 71 is opened with the dustproof cover 90 attached to the manual feed tray 72, the abutment portion 91C is pressed by the right cover 71, and the dustproof cover 90 moves in the direction of removal from the manual feed tray 72 (the direction of arrow B2). The movement of the dustproof cover 90 in the removal direction is restricted at the position where the restricting rib 91G abuts against the abutting rib 72E, preventing the dustproof cover 90 from falling off the manual feed tray 72. When the right cover 71 is closed, the dustproof cover 90, which has moved to the position shown in FIG. 23 , changes to a position tilted downward toward the right cover 71. As a result, the dustproof cover 90 moves toward the right cover 71 under its own weight and returns to a predetermined position, such as the position where it is attached to the manual feed tray 72, just like the dustproof cover 90 shown in FIG. 18( b).

[0071] Next, a configuration for reducing the frictional force generated between the dust cover 90 and the manual feed tray 72 will be described. Specifically, the upper rail 91E and the lower rail 91F, which are the sliding portions of the dust cover 90 with the manual feed tray 72, can be made of a material with a lower friction coefficient than the remaining portions of the base portion 91. The "other portions" here refer to all other portions of the base portion 91, or may refer to only a portion of the other portions. For example, in this embodiment, the base portion 91 is formed of a resin material with a friction coefficient of approximately 0.3, and the upper rail 91E and the lower rail 91F can be made of a material with an even lower friction coefficient. Furthermore, as shown in FIG. 24 , low-friction members 87A-87C with a lower friction coefficient than all or a portion of the base portion 91 may be provided at the sliding portions of the upper rail 91E and the lower rail 91F with respect to the manual feed tray 72. The low-friction members 87A-87C may be formed by attaching a low-friction material such as a sheet member to the upper rail 91E or the lower rail 91F, or by applying a coating such as quick-drying grease to the upper rail 91E or the lower rail 91F. However, a configuration in which the rail itself is made of a low-friction material may be combined with a configuration in which a low-friction member is attached to the sliding portion, or such a configuration may be adopted for only some of the sliding portions or only part of the sliding portions.

[0072] 25 and 26, roller members 80 that can rotate in the directions of the double arrows in Fig. 26 can be provided on upper rail 91E and lower rail 91F. This reduces the frictional force that occurs between dustproof cover 90 and manual tray 72. Roller members 80 are inexpensive and easy to replace.

[0073] These friction-reducing structures can be applied to each of the above-described embodiments. For example, by applying the structure to a dust cover 90 having a biasing member, such as that shown in FIG. 17 , the biasing member can move the dust cover 90 in the attachment direction relative to the manual feed tray 72 with a smaller biasing force. Furthermore, by applying the structure to a dust cover 90 having a restricting portion, such as that shown in FIG. 21 , the dust cover 90 can be more easily moved in the attachment direction relative to the manual feed tray 72 by its own weight. However, the friction-reducing structure described above is not limited to the upper rail 91E or the lower rail 91F. If the dust cover 90 slides on the manual feed tray 72 at other locations, the structure may be provided at those locations, or the friction-reducing structure may be provided on the manual feed tray 72 itself. By providing the dust cover 90 with a friction-reducing structure, the friction between the dust cover 90 and the manual feed tray 72 can be reduced without changing the external configuration of the manual feed tray 72. In other words, when the dust cover 90 is added as an option, the friction can be reduced without changing the configuration of the device main body.

[0074] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[0075] In the above explanation, the dustproof cover 90 (cover member) falls off from the manual feed tray 72 when it is pushed by opening or closing the right cover 71. However, examples of the cover member falling off are not limited to this. For example, it may be that an operator unintentionally applies force in this direction, or the cover member may be pushed when another member on the device main body is operated. Regardless of the type of force applied to the cover member, the configuration of the present invention can prevent the cover member from falling off from the manual feed tray.

[0076] The image forming apparatus according to the present invention is not limited to the monochrome image forming apparatus shown in Fig. 1, but may also be a color image forming apparatus, a copier, a printer, a facsimile, or a combination machine of these. Furthermore, the main body of the apparatus to which the sheet feeding apparatus of the present invention feeds sheets does not necessarily have to be an image forming apparatus.

[0077] Sheets include paper (plain paper), as well as cardboard, postcards, envelopes, tissue paper, coated paper (coated paper, art paper, etc.), tracing paper, OHP sheets, plastic film, prepreg, copper foil, and the like.

[0078] The aspects of the present invention are as follows, for example. <1> a manual feed tray on which sheets to be supplied to the apparatus main body are placed; a cover member that is slidably attached to the manual feed tray and covers a sheet placement surface of the manual feed tray; a holding member attached to the device body and holding the manual feed tray, The sheet feeding device is characterized by comprising a biasing member that connects the cover member and the holding member and biases the cover member in a direction in which the cover member is attached to the manual feed tray. <2> The biasing member is a tension spring. <1> 1 is a sheet feeding apparatus according to the present invention. <3> The biasing member is a rubber member. <1> 1 is a sheet feeding apparatus according to the present invention. <4> the holding member is an opening / closing member that is attached to the device body so as to be openable and closable, The manual feed tray is rotatably provided with respect to the holding member, and the rotation axis direction thereof is set in the same direction as the rotation axis direction of the opening and closing operation of the holding member. <1> from <3> ,or <9> The sheet feeding device according to any one of the preceding claims. <5> The apparatus further includes a rotation restricting portion that restricts an opening angle of the manual feed tray relative to the holding member in a rotation direction to a certain value or less when the holding member is open relative to the apparatus body. <4> 1 is a sheet feeding apparatus according to the present invention. <6> At least one of the manual feed tray and the cover member has a sliding portion formed of a material having a smaller coefficient of friction than other portions of the manual feed tray or the cover member. <1> from <5> ,or <9> The sheet feeding device according to any one of the preceding claims. <7> At least one of the manual feed tray and the cover member is provided with a rotatable roller member at a sliding portion of the manual feed tray and the cover member. <1> from <5> ,or <9> The sheet feeding device according to any one of the preceding claims. <8> the cover member has a base portion that is slidably attached to the manual feed tray, and a cover portion that is rotatably attached to the base portion and covers the sheet placement surface, The biasing member connects the base portion and the holding member. <1> from <3> or <1> relating to <4> from <7> The sheet feeding device according to any one of the preceding claims. <9> a manual feed tray on which sheets to be supplied to the apparatus main body are placed; a cover member that is slidably attached to the manual feed tray and covers a sheet placement surface of the manual feed tray, This sheet feeding device is characterized by having a regulating section that regulates the movement of the cover member in the removal direction relative to the manual feed tray at a position where the cover member has moved in the removal direction opposite to the attachment direction from the position where it was attached to the manual feed tray. <10> the device main body; <1> from <9> An image forming apparatus includes any one of the sheet feeding devices, and forms an image on the sheet. [Explanation of symbols]

[0079] 1. Copiers (image forming devices) 2 Image forming device main body (device main body) 70 Manual paper feeder (sheet feeder) 71 Right cover (retaining member or opening / closing member) 72 Manual feed tray 72B Sheet placement surface 77 Tension spring (biasing member) 78 Rubber member (biasing member) 79 Regulatory Department 80 Roller parts 86 Rotation control part 87A~87C Low friction materials 90 Dustproof cover (cover material) B1 Direction to attach the dust cover to the manual feed tray (direction to attach the cover member to the manual feed tray) B2 Direction to remove the dust cover from the manual feed tray (direction to remove the cover from the manual feed tray) S seat α1, α2 opening angle [Prior art documents] [Patent documents]

[0080] [Patent Document 1] Patent No. 6493738

Claims

1. a manual feed tray on which sheets to be supplied to the apparatus main body are placed; a cover member that is slidably attached to the manual feed tray and covers a sheet placement surface of the manual feed tray; a holding member attached to the device body and holding the manual feed tray, a biasing member that connects the cover member and the holding member and biases the cover member in a direction in which the cover member is attached to the manual feed tray;

2. 2. The sheet feeding apparatus according to claim 1, wherein the biasing member is a tension spring.

3. 2. The sheet feeding device according to claim 1, wherein the biasing member is a rubber member.

4. the holding member is an opening / closing member that is attached to the device body so as to be openable and closable, 2. The sheet feeding device according to claim 1, wherein the manual feed tray is rotatable relative to the holding member, and the rotation axis direction of the manual feed tray is the same as the rotation axis direction of the opening and closing operation of the holding member.

5. 5. The sheet feeding device according to claim 4, further comprising a rotation restricting portion that restricts an opening angle of the manual feed tray relative to the holding member in a rotation direction to a certain value or less when the holding member is open relative to the device body.

6. 2. The sheet feeding device according to claim 1, wherein the sliding portions of at least one of the manual feed tray and the cover member are formed of a material having a lower coefficient of friction than other portions of the manual feed tray or the cover member.

7. 2. The sheet feeding device according to claim 1, wherein at least one of the manual feed tray and the cover member is provided with a rotatable roller member at a sliding portion of the manual feed tray and the cover member.

8. the cover member has a base portion that is slidably attached to the manual feed tray, and a cover portion that is rotatably attached to the base portion and covers the sheet placement surface, 2. The sheet feeding device according to claim 1, wherein the biasing member connects the base portion and the holding member.

9. a manual feed tray on which sheets to be supplied to the apparatus main body are placed; a cover member that is slidably attached to the manual feed tray and covers a sheet placement surface of the manual feed tray, A sheet feeding device characterized in that it is provided with a regulating portion that regulates the movement of the cover member in the removal direction relative to the manual feed tray at a position where the cover member has moved in the removal direction opposite to the attachment direction from the position where it is attached to the manual feed tray.

10. the device main body; An image forming apparatus comprising: the sheet feeding device according to claim 1 ; and the image forming apparatus forming an image on the sheet.

Images