JP2004330665A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a writing device using an LED that can readily remove a contamination adhered to a light emitting face thereof and can readily carry out a cleaning operation by a simple structural member. <P>SOLUTION: A cleaning member 40 moved by a wire 38 is provided to this image forming apparatus, and a brush 41 is slid relative to the light emitting face of the writing device 16 so that a contamination is removed. The wire for moving the cleaning member is in an endless shape and is driven by pulleys respectively disposed to both ends of the writing device in the longitudinal direction. At the end section of the writing device, an arm 42 is swung to the outside by an engagement/release member 31, and then a slider 43 is taken off the moving position of the wire 38 and is stopped to be held. After that, the engagement/release member 31 is circulated to the opposite side to be engaged with the slider 43a at a side of an arm member 42a, and then the engagement/release member 31 drives to move the slider 43 to the returning direction. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a device for cleaning a light emitting surface of a writing device that irradiates writing light to an image carrier, and more particularly, to an image forming device in which a mechanism for reciprocating a cleaning member by a wire is simplified.
[0002]
[Prior art]
2. Description of the Related Art In an image forming apparatus that forms an image on a sheet using an electrophotographic method, a charging member uniformly charges a photosensitive drum as an image carrier, and then irradiates the image light from a writing device. Thus, an electrostatic latent image is formed, and toner is adhered to the electrostatic latent image to visualize it as a toner image. Then, the toner image formed on the photosensitive drum is transferred to a sheet, the toner image is fixed on the sheet through a fixing device, and is discharged to a discharge tray. As a writing device for irradiating the image carrier with light, in addition to a method using laser light, a writing head having a large number of LEDs (light emitting diodes) is used. A method of performing writing by emitting light according to image information is also frequently used. The writing device using the LED irradiates the photosensitive drum with light at a position close to the developing device to perform the writing operation. The adhesion of the toner or the like causes a problem that light emitted to the photosensitive drum is weakened. In the case where the potential difference between the electrostatic latent image portion and the other portion not irradiated with light in the photosensitive drum is small, defects such as a decrease in density of the toner image and an unclear image are caused. Occurs. Therefore, in order to solve the above-described problem, it has been proposed to provide a cleaning unit, and when the dirt on the light emitting surface is detected, move the cleaning member to remove the dirt. , Patent Document 1).
[0003]
[Patent Document 1]
JP-A-2001-92316
[Problems to be solved by the invention]
However, when using a cleaning member for cleaning the light emitting surface of a writing device using an LED as in the above-described conventional example, depending on the position of the dirt detecting means, it is not possible to obtain accurate dirt detection information. There's a problem. In addition, it is necessary to arrange a drive mechanism for moving the cleaning member with respect to the writing device in a narrow space around the writing device, but the conventional cleaning member drive mechanism cannot sufficiently meet the demand. Met. In addition, in order to move the cleaning member along the light emitting surface of the writing device, many improvements are also desired in a motor driving method and a mechanism for guiding the cleaning member. It is.
[0005]
An object of the present invention is to provide a device which can simplify a driving mechanism of a cleaning member and can easily perform a cleaning action, instead of the conventional cleaning means as described above.
[0006]
[Means for Solving the Problems]
The present invention relates to an image forming apparatus in which a writing unit is disposed in an image recording unit for an image carrier, and a charged image carrier is irradiated with image light from the writing unit to form an electrostatic latent image. The invention according to claim 1, wherein the light-emitting surface of the writing device is disposed so as to face the light-emitting surface, and a cleaning member for cleaning the light-emitting surface is provided movably in a length direction of the writing member. A cleaning member guide means provided on both sides of the writing device, a retreat area of the cleaning member provided at both ends in the longitudinal direction of the writing device, and a moving device for moving the cleaning member. A pulley disposed outside, an endless wire that extends over the two pulleys, an engaging member provided on the wire, and an engaged member corresponding to the engaging member provided on both sides in the movement direction of the cleaning member; By driving the wire, the engaging member provided on the wire is engaged with the engaged member of the cleaning member, and the cleaning member is reciprocated along the writing device. Light emitting surface And performing cleaning action.
[0007]
The invention according to claim 2 is characterized in that the cleaning member is reciprocated by driving the wire in only one direction.
[0008]
The invention according to claim 3 is characterized in that, when the cleaning member is moved to the retracted position at the end of the writing device, the cleaning member is separated from the drive by the wire and stopped by the engagement releasing means provided at the retracted position. And
[0009]
The invention according to claim 4 is configured such that the motor for driving the wire is driven in one direction, and the cleaning member is moved to one end by engaging the engaging member with the engaged member. In the configuration, the cleaning member is stopped at the retreat area at the end of the writing device, and thereafter, the engaging member provided on the wire is engaged with the other engaging member of the cleaning member to move the return path. It is characterized by doing.
[0010]
With the above-described configuration, the configuration of the device for cleaning the light emitting surface of the writing device can be simplified, and the device can be easily incorporated without largely changing the configuration of the writing device. Further, since a driving means for reciprocating the cleaning member along the writing device can be achieved by the wire and its driving mechanism, it can be applied to a small-sized image forming apparatus. By cleaning the light emitting surface of the writing device, the light output from the writing device toward the photosensitive drum is not affected by dirt attached to the light emitting surface and becomes unclear, so that the recording with good image quality can be performed. It is possible to create paper.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, the configuration of an image forming apparatus to which the cleaning unit of the present invention can be applied will be described with reference to FIG. The example shown in FIG. 1 is configured as a small-sized image forming apparatus, and a paper feeding unit 3 provided at a lower portion of the apparatus main body is provided with a paper feeding tray 3 capable of storing paper of an arbitrary size. The paper is taken out one by one by the paper feed roller 4 and fed to the paper transport path 5. In the paper transport path 5, transport roller devices 5a and 5b are arranged at a predetermined interval, and the toner image is transferred to the paper transported in the paper transport path 5 when passing through the recording unit 7. Then, the toner image is fixed on the sheet by the fixing device 8, and is discharged to the discharge tray 9 a by the discharge roller device 9. In addition to the paper feed system from the paper feed tray 3, a manual feed tray 6 that can be opened and closed is arranged on the side of the apparatus. To feed paper toward the paper transport path 5 by the paper feed roller 6a.
[0012]
In the image forming apparatus 1, the recording unit 7 includes a photosensitive unit 10 provided with a photosensitive drum 12 and a developing unit 20 for supplying toner to the photosensitive drum 12. The two units 10 and 20 are combined as shown in the figure and attached to the recording unit 7 of the apparatus main body. In the photoreceptor unit 10, a charging brush 15 as a charging member and a memory removing member 14 are disposed on a photoreceptor drum 12 supported by a unit frame 11. A writing unit 16 is disposed at a position corresponding to an upper portion of the photosensitive drum 12, and a transfer member 17 is disposed at a lower portion. The developing roller 25 of the developing unit 20 is located on the downstream side.
[0013]
In the photoreceptor unit 10, a predetermined voltage is applied to the photoreceptor drum by a charging brush 15 to uniformly charge the photoreceptor drum, and image light is emitted from a writing unit 16 including an LED (light emitting diode). To form an electrostatic latent image. Then, toner is supplied from the developing roller 25 to the electrostatic latent image formed on the photosensitive drum 12 to be visualized as a toner image, and is sandwiched between the transfer roller 17 and the photosensitive drum 12. A predetermined potential is supplied to the transfer roller 17 for the conveyed sheet, and the toner image is transferred to the sheet. The sheet on which the toner image has been transferred is conveyed toward the fixing device 8, where the toner image is fixed and discharged. Further, after the toner image is transferred onto the sheet, the toner and the like remaining on the photosensitive drum are disturbed by the brush of the memory removing member 14, and the adhesion is weakened to be uniformly dispersed. Later, the charging brush 15 charges the battery to a predetermined potential.
[0014]
The developing unit 20 operates to send out the toner contained in the toner hopper 22 toward the supply roller 24 while stirring the toner with the paddle 23 provided on the shaft 23a. The toner is supplied to the photosensitive drum 12 by the developing roller 25 arranged correspondingly. Then, while rubbing the toner between the supply roller 24 and the developing roller 25, a predetermined potential is applied to charge the toner, and the toner is attached to the surface of the developing roller 25. Is formed. The toner carried on the developing roller 25 is supplied toward the electrostatic latent image on the photosensitive drum 12, and the toner remaining on the surface of the developing roller after that is newly supplied to the supply roller 24. The toner is mixed with the supplied toner, applied with a charging effect again, and supplied toward the developing area.
[0015]
A photoreceptor unit 10 and a developing unit 20 are mounted as a unit on a mounting portion provided on a main body frame of the image forming apparatus, and the photoreceptor drum 12 and the developing roller 25 are positioned at predetermined positions. In addition, as shown in FIG. 1, when using a method in which the two units are mounted from above the main body frame, a cover member that can be opened and closed from above is provided for the mounting portion. Then, after the two units are combined and mounted, the cover member that covers the upper portion is closed, so that the sensor member can output information that detects the mounting of the unit and the closed state of the cover member.
[0016]
When two units are mounted on the mounting portion, the two units are combined by using any means, and one of the combined units is operated with respect to the detection means. In the image forming apparatus configured as described above, the image forming apparatus may be mounted on the recording unit of the apparatus main body in combination with the photosensitive unit and the developing unit mounted on the recording unit, or may be configured as the one unit. It is also possible to use an arbitrary structure such as mounting on a mounting unit provided in a recording unit.
[0017]
Note that, in the image forming apparatus described in FIG. 1, the configuration of a cleaning unit that cleans a light emitting surface of the writing device (hereinafter, referred to as an LED) 16 facing the photosensitive drum is shown. In the writing device using the LED, as in the case of the conventional device, a device in which a row of Selfoc lenses is arranged in combination with a row of light emitting diodes on the photosensitive drum side is used. Indicates the end surface of the row of the Selfoc lenses on the photosensitive drum side.
[0018]
In the example shown in FIG. 2, a guide groove 30 having a predetermined depth is formed on both sides in the width direction of the writing device 16 described in FIG. The mechanism for performing the cleaning action by sliding the 40 brush members 41 has been described. Guide grooves 30, 30 a extending in the longitudinal direction are formed on both side walls in the width direction of the LED 16. The cleaning member 40 includes left and right sliders 43, 43a inserted into the guide grooves 30, 30a provided in the LED 16 and slidably provided, and a brush member 41 having a substantially upward U-shaped arm member 42, 42a. The cleaning member 40 is moved so that the brush member 41 slides on the light emitting surface 16 a of the LED 16. The sliders 43 and 43a are formed of a resin material having a small coefficient of friction. The arm members 42 and 42a are formed of plate members having a spring property so that the brush member 41 comes into light contact with the light emitting surface 16a of the LED 16. Is provided.
[0019]
As shown in FIGS. 3 and 4, retreat areas 33 and 33 a for retreating the cleaning member 40 from the light emitting area of the LED 16 are provided on both sides in the longitudinal direction of the LED 16. A driving member 34 for moving the cleaning member 40 along the LED 16 includes a pair of pulleys 36, 37 provided one each on the outside in the longitudinal direction further than the retreat areas 33, 33a, and one pulley 36. And a wire 38 wound between the pulleys. The wire 38 has at least one engaging member 39. When the cleaning member 40 is reciprocated along the writing device 16, engaged portions 44, 44 a protruding outward from the sliders 43, 43 a are provided, and grooves are formed in the engaged portions. The engaging member 39 provided on the wire 38 is locked so that the light emitting surface 16a of the writing device is moved while being cleaned.
[0020]
In the example shown in FIGS. 3 and 4, when the cleaning member 40 is moved to one side along the writing device 16, the engaging member 39 of the wire 38 is engaged with the engaged portion 44 of the cleaning member 40. Let it tow. When the cleaning member 40 reaches one end (the drive pulley 36 side) of the writing device, the wire 38 is provided at the longitudinal end of the writing device, and the engagement member 31 protrudes outward in the width direction. The cleaning member 40 is stopped at the retreat area 33 because the traction action on the cleaning member 40 is interrupted by being guided to a position disengaged from the engaged portion 44. Next, when the engaging member 39 of the wire 38 is moved to the other side around the driving pulley 36, the engaging member 39 is engaged with the engaged portion 44a of the slider 43a, and Until the retracting area 33a on the pulley 37 side is reached, the cleaning member 40 is moved in the return direction, and performs the action of cleaning the light emitting surface 16a of the writing device.
[0021]
In the vicinity of both ends of the writing device, the engagement release members 31 and 31a provided in correspondence with the retraction area in order to interrupt the traction action by the wire 38 are provided outward from an arbitrary position of the main body of the writing device. It is provided so as to protrude. Therefore, in the upstream portion of the position where the wire is guided to the outside of the traveling path by the release member, the pressing member 32 is provided together with the urging means in combination with the engagement release member 31, and the wire 38 is written to the retreat area. The guide is guided along the guide groove 30 of the member 16, and is guided outward at a steep angle between the disengagement member 31 and the pressing member in the retreat area so that the member can be separated from the engaged member of the cleaning member. It is good to
[0022]
In the example described with reference to FIG. 2 and subsequent figures, when the cleaning member 40 is moved by a wire, an engaged portion is provided on a slider so that an engaging member 39 provided on the wire 38 is removed outside the traveling path. The case where a means for guiding and stopping the cleaning member 40 in the retreat area 33 is used is described. On the other hand, in another embodiment of the present invention described below with reference to FIG. 5, the arm members 42 and 42a on both sides of the cleaning member 40 that support the brush member 41 are formed of members having spring properties, and the arm member The member for engaging the engagement member 39 with the slider 43 provided in the first member is integrally provided. 6 and 7, the disengagement members 31, 31a are respectively protruded corresponding to both ends of the movement path of the cleaning member 40, that is, the retreat areas described in FIGS. Provided.
[0023]
In the embodiment of the cleaning member illustrated in FIGS. 5 to 7, as described in FIGS. 3 and 4, the brush 41 is moved while sliding on the light emitting surface 16 a of the writing device 16. When performing the cleaning action, the arm members 42 and 42a on both sides of the cleaning member 40 are provided with the sliders 43 and 43a provided on the respective upper end portions in the guide grooves 30 and 30a provided on both sides of the main body of the writing device 16. It is slid to provide guidance. In the retreat areas 33 and 33a of the writing device 16, one of the disengagement members 31 and 31a bends one arm member outward to separate the slider from the guide groove, and the wire 38 And releasing the engaging member from the slider. As described above, even when one arm member of the cleaning member 40 is removed from the guide groove, writing is performed by the other arm member and the slider being supported by the guide groove and the elasticity of the two arm members. Since the function of supporting the cleaning member with respect to the apparatus can be maintained, the cleaning member does not drop.
[0024]
For example, in the example illustrated in FIG. 6, in order to stop the cleaning member 40 in the retreat area 33, the engagement release member 31 is provided so as to protrude from a side portion of the main body of the writing device 16. One of the arm members 42 is guided outwardly by the disengagement member 31 and is bent outward. Then, since the engaged portion 44 of the slider 43 is disengaged from the pressing member 32, the cleaning member 40 is stopped at that position, but the wire 38 is moved as it is, and the pressing member passes through the driving pulley. The brush 41 goes around the other side of the writing device 16 and is engaged with the slider 43a, and the brush 41 cleans the light emitting surface while moving the cleaning member 40 in the return direction.
[0025]
At the end of the movement in the return direction, in which the cleaning member 40 is moved to the driven pulley side, an engagement release member 31a is provided on the other side of the writing device 16 as shown in FIG. The other arm member 42a is removed from the pressing member 39 of the wire 38 and stopped. Then, the cleaning member is stopped at the retracted position on the driven pulley side, and waits for the next cleaning operation, but the cleaning member 40 stopped at the standby position 33 is opposed to the cleaning member 40. When the engaging member 39 turned to the side locks the other engaged portion 44a and moves in the return direction, the arm member 42 slides on the slope of the disengagement member 31 and returns. 43 enters the guide groove 30. Therefore, in the cleaning section for the writing device 16, the two arm members of the cleaning member 40 can move along the guide grooves on both sides of the writing device to perform the cleaning operation of the light emitting surface of the LED.
[0026]
In the example described with reference to FIGS. 3 and 4, the case where the motor is driven in one direction and the engaging member 39 provided on the wire 38 is circulated by two pulleys has been described. In order to reciprocate 40, it is possible to provide a drive mechanism for rotating the motor forward and backward. For this purpose, the wire 38 is not provided with the engaging member 39, but the one corresponding to the engaging member is configured as a fixing portion to the arm, and the movement of the cleaning member 40 is stopped at the retreat positions 33 and 33a. Good. Then, for a section in which the writing device 16 needs to be cleaned, a pulse or the like set to the motor is set in the control device, and the cleaning member 40 is reciprocated by the number of pulses applied to the pulse motor. The light emitting surface of the LED can be cleaned.
[0027]
In addition, a sensor or a micro switch is arranged at a predetermined position on the movement path of the cleaning member, and when the cleaning member 40 is detected, the movement of the motor is stopped, and then the motor is driven in reverse. It is good to set the driving method of. Therefore, when a mechanism for reciprocating the cleaning member by rotating the motor in the normal and reverse directions as described above is used, there is no need to provide an engagement releasing member on the side of the writing device, and the configuration of the device is simplified. It is possible to cope with it.
[0028]
The operation of cleaning the light emitting surface of the writing device using the cleaning member can be performed at an arbitrary timing. For example, the cleaning timing is set in the control device of the image forming apparatus, The drive member of the cleaning device can be operated when the number of recording papers is created. Further, the apparatus can be configured so that the operator can determine the dirt state of the writing apparatus from the screen of the recording paper (the sharpness of the image) and perform the cleaning operation. In addition, in the evacuation areas arranged at both ends of the writing device, in order to hold the cleaning member in a stable state, it is possible to provide holding means such that the lower surface of the cleaning member slides. If the cleaning member is held at the stop position by such holding means, even if an impact or the like is applied to the apparatus when the apparatus is stopped, it can be safely held.
[0029]
【The invention's effect】
With the configuration described above, the configuration of the device for cleaning the light emitting surface of the writing device can be simplified, and the device can be easily incorporated without largely changing the configuration of the writing device. Further, since a driving unit for reciprocating the cleaning member along the writing device can be achieved by the wire and its driving mechanism, the driving unit can be applied to a small-sized image forming apparatus. By cleaning the light emitting surface of the writing device, the light output from the writing device toward the photosensitive drum is not affected by the dirt attached to the light emitting surface and becomes unclear, and the recording with good image quality is performed. It is possible to create paper.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram illustrating a configuration of an image forming apparatus.
FIG. 2 is an explanatory diagram of an example in which a cleaning device is combined with a writing device.
FIG. 3 is a plan view showing a configuration of a writing device and a driving mechanism of a cleaning member.
FIG. 4 is a plan view of FIG. 3;
FIG. 5 is an explanatory diagram of a second embodiment of the present invention.
FIG. 6 is an explanatory diagram of a mechanism for stopping a cleaning member at one end.
FIG. 7 is an explanatory view of stopping a cleaning member at the other end.
[Explanation of symbols]
1 image forming apparatus, 2 paper feed unit, 3 paper feed tray,
4 paper feed roller, 5 paper transport path, 5a / 5b transport roller device,
6 manual feed tray, 7 recording unit, 8 fixing device,
9 discharge roller device, 10 photoconductor unit,
11 unit frame, 12 photoconductor drum,
14 memory removing member, 15 charging member, 16 writing member,
17 transfer roller, 20 developing unit,
21 unit frame, 22 toner hopper, 23 paddle,
24 supply roller, 25 developing roller, 26 blade mounting part,
29 blades, 30 guide grooves, 31 disengagement members,
32 pressing member, 33 evacuation area, 34 driving member,
35 motor, 36 driving pulley, 37 driven pulley,
38 wires, 39 engaging members, 40 cleaning members,
41 brush member, 42 arm member, 43 slider,
44 Engaged part.

Claims (4)

An image forming apparatus in which a writing unit is arranged in an image recording unit for an image carrier, and an electrostatic latent image is formed by irradiating a charged image carrier with light of an image from the writing unit.
It is arranged to face the light emitting surface of the writing device, and a cleaning member for cleaning the light emitting surface is provided movably in the length direction of the writing member,
Guide means for a cleaning member provided on both sides in the width direction of the writing device;
A retreat area for a cleaning member provided at both ends in the longitudinal direction of the writing device;
A pulley disposed outside both ends of the writing device in a longitudinal direction for moving the cleaning member;
An endless wire spanning the two pulleys, an engaging member provided on the wire,
An engaged member corresponding to the engaging member provided on both sides in the movement direction of the cleaning member,
By driving the wire, the engaging member provided on the wire is engaged with the engaged member of the cleaning member, and the cleaning member is reciprocated along the writing device. An image forming apparatus that performs a cleaning action. The image forming apparatus according to claim 1, wherein the cleaning member is reciprocated by driving the wire only in one direction. 2. The cleaning member according to claim 1, wherein when the cleaning member is moved to a retreat position at an end of the writing device, the cleaning member is separated from driving by a wire and stopped by an engagement release unit provided at the retreat position. Image forming apparatus. The motor for driving the wire is configured to be driven in one direction, and after the cleaning member is moved to the one end by engaging the engaging member with the engaged member, the cleaning member is moved to one end. The cleaning member is stopped in a retreat area of the portion, and thereafter, the engaging member provided on the wire is engaged with the other engaging member of the cleaning member to move the return path. Item 4. The image forming apparatus according to any one of Items 1 to 3.

Images