JP2005091980A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the generation of deformation on a shaft part connecting an operation lever 13 to a transfer material carrying unit 19 even when the operation lever 13 for operating a touching/separating mechanism between a carrying belt 3 and a photoreceptor repeatedly performs unit drawing operation, in an image forming apparatus provided with the transfer material carrying unit 19 comprising the touching/separating mechanism having the operation lever 13 to be gripped by an operator and the shaft part fixed on the operation lever 13 and capable of approaching or separating the carrying belt 3 to/from the photoreceptor in accordance with the rotation of the shaft part due to the rotation of the operation lever 13 and allowed to be attached/detached to/from an apparatus body and constituted so that the transfer material carrying unit 19 is detached from the apparatus body by allowing the operator to pull the operation lever 13 along the axial direction of the shaft part. <P>SOLUTION: A projected part 13c is formed as a rotation regulation means for regulating the turning operation of the operation lever 13 around a junction part between the operation lever 13 and the shaft part along a virtual plane including the axial line of the shaft part. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus using an electrophotographic system such as a copying machine, a printer, and a facsimile machine.

In general, in an image forming apparatus using an electrophotographic process, an electrostatic latent image corresponding to an original image is formed on a photoconductor uniformly charged in advance with a predetermined polarity. This electrostatic latent image is developed by a developing unit provided at a predetermined position around the photoreceptor. That is, the electrostatic latent image is developed with toner, which is a charged fine powder supplied from the developing unit, to form a toner image. The toner image formed on the photoconductor reaches the transfer unit by the rotation of the photoconductor, and is transferred to the transfer material conveyed to the transfer unit. Thereafter, the toner image transferred to the transfer material is fixed to the transfer material by the fixing unit.
In an image forming apparatus that conveys a transfer material to a transfer position around a photosensitive member by a transfer conveyance belt, the transfer conveyance belt is unitized together with other transfer apparatuses and the like, and this unit is detachably attached to the apparatus main body. There are many things. In this case, when a paper jam occurs around the transfer position, it is pulled out from the apparatus main body after the unit, thereby facilitating the paper jam handling operation (hereinafter referred to as jam processing).

  Conventionally, when a unit including a transfer material transport belt is pulled out from the apparatus main body, the photoconductor and the transfer material transport belt come into contact with each other during the pulling operation. There was a risk of scratching. Therefore, a configuration is known in which a mechanism for performing a contact / separation operation for separating and approaching the transfer material conveyance belt from the photosensitive member and an operation lever for operating the mechanism are installed in the apparatus main body (see, for example, Patent Document 1). In the image forming apparatus having this configuration, jam processing is performed according to the following procedure. First, by operating an operation lever provided on the apparatus main body, the transfer material conveyance belt is separated from the photosensitive member, and thereafter, the unit is pulled out using a unit drawer handle provided in the unit, and the jammed paper is removed. remove.

  In the above-described image forming apparatus, since the operation lever is provided in the apparatus main body, the handle portion used when pulling out the unit is provided on the unit side separately from the operation lever. For this reason, the operator must operate the holding lever when pulling it out, move the transfer belt away from the photosensitive member, and then carry out the complicated work of pulling the unit by holding it to the unit pull-out handle. . In order to improve the operability and reduce the number of parts by omitting such a holding operation, a contact / separation mechanism for the operation lever and transfer material transport belt is provided on the unit side, and the operation lever is a handle for pulling out the unit. The structure which used as a part was proposed (refer patent document 2).

JP 09-236993 JP-A-11-249530

However, in the configuration of the above-mentioned Patent Document 2, when the unit pulling operation is repeatedly performed, the following problem occurs.
FIG. 4 shows the shape of the operation lever used in Patent Document 2. The operation lever 13 has a handle portion 13a in which an operator holds the lever. The shaft portion 11 for transmitting the rotation operation of the operation lever to the transfer belt contacting / separating mechanism in the unit is connected to a handle support portion 13b provided at one end of the handle portion 13a. In this configuration, the contact / separation operation of the transfer belt contact / separation mechanism is performed by rotating the lever 13. In order to realize such a contact / separation operation, the operation lever 13 and the unit 19 are connected only by the shaft portion. Moreover, the shaft portion 11 is connected at the end of the handle portion 13a. For this reason, when the handle portion 13a is pulled with a force F as shown in the drawing to pull out the unit, a rotational force is applied around the point P. As a result, the bending moment M of the shaft portion 11 works. As a result, when the pulling-out operation is repeatedly performed, the shaft portion 11 is deformed.
The present invention has been made in view of the above problems, and an object of the present invention is to serve as a handle for pulling out a transfer material conveyance unit having a transfer material conveyance member from the apparatus main body, and to convey the belt and the photoconductor. It is an object of the present invention to provide an image forming apparatus in which an operating lever for operating a contact / separation mechanism between the operating lever and the mechanism does not cause deformation in a shaft portion connecting the operating lever and the unit even when the unit pulling operation is repeated.

In order to achieve the above object, the invention of claim 1 is grasped by an operator and a transfer material conveying member that conveys a transfer material so as to pass a transfer position to which a toner image on an image carrier is transferred. An operation lever having a handle, a shaft fixed to one end of the handle, and a rotation of the shaft that occurs when the operation lever rotates around the one end. A transfer material transport unit that can be attached to and detached from the apparatus main body and has an approach / separation mechanism for moving the transfer material transport member closer to or away from the apparatus body. In the image forming apparatus configured such that the transfer material transport unit is removed from the apparatus main body by pulling along the axial direction of the image forming apparatus, along an imaginary plane including the axis of the shaft portion with the one end portion as the center. Restricting the rotation of the operating lever It is characterized in that it has a dynamic regulating means.
According to a second aspect of the present invention, in the image forming apparatus of the first aspect, the rotation restricting means is provided on the opposite side of the grip portion with the one end portion interposed therebetween, and is provided on the outer plate of the transfer material conveying unit. It is characterized by comprising a rotation restricting member that comes into contact.
According to a third aspect of the present invention, in the image forming apparatus of the second aspect, a rotation range regulating member that abuts on the rotation regulating member and regulates the rotation range of the operation lever is provided on the outer plate. It is characterized by.
4. The image forming apparatus according to claim 1, wherein the operation lever is provided with an extending portion extending from the one end portion to the opposite side of the handle portion, and the rotation restricting means is arranged in the axial direction of the shaft portion. And a rotation restricting member provided on the outer plate of the transfer material transport unit so as to come into contact with the extended portion when the operation lever is pulled along.
According to a fifth aspect of the present invention, in the image forming apparatus according to the first, second, third, or fourth aspect, the transfer material conveyance unit includes a transfer device having the transfer material conveyance member, and a transfer material on which a toner image is transferred. And a fixing device for fixing the toner image.
According to a sixth aspect of the present invention, in the image forming apparatus according to the fifth aspect, the transfer material transport unit includes a registration roller.

  In the image forming apparatus according to any one of the first to sixth aspects, when the transfer material transport unit is pulled out, the rotation of the operation lever along the virtual plane including the axis centering on the connecting portion between the shaft portion and the handle portion is regulated. By having the movement restricting means, the bending moment applied to the shaft portion can be reduced.

  According to the first to sixth aspects of the present invention, even if the operation of the unit is repeatedly performed by using the operation lever also serving as the unit pull-out handle, the shaft portion connecting the operation lever and the transfer material transport unit is deformed. There is an effect of preventing this.

  Hereinafter, embodiments to which the present invention is applied will be described with reference to the drawings. FIG. 1 is an explanatory view of a transfer material transport device and its peripheral part of an image forming apparatus to which the present invention is applied. As can be seen from FIG. 1, the image forming apparatus of this embodiment has a photosensitive drum 1 as an image carrier on which an electrostatic latent image corresponding to image information is formed. In addition to the photosensitive drum, examples of the image carrier include an intermediate transfer member and a magnetic image carrier.

  The following members are provided around the photosensitive drum 1. There is a charging charger 22 for charging the surface of the photosensitive drum 1, and an electrostatic latent image is formed on the surface of the photosensitive drum 1 by irradiating the photosensitive drum 1 after the charging process with image data of light. An exposure apparatus is provided. The developing unit 20 that visualizes the electrostatic latent image by supplying toner to the electrostatic latent image formed on the surface of the photosensitive drum 1 and forms a toner image on the photosensitive drum 1 is provided on the photosensitive member. It is installed downstream of the exposure apparatus in the drum rotation direction. On the downstream side of the developing device 20, a transfer device (transfer bias roller 5) for transferring the toner image on the photosensitive drum 1 to a transfer material such as copy paper, and the photosensitive drum 1 for the next copying process after the transfer process is completed. A cleaning unit 21 is provided for cleaning.

  In addition, registration rollers 2a and 2b are provided on the upstream side of the transfer material conveyance belt 3 in the conveyance direction to feed out a transfer material fed from a sheet feeding unit (not shown) at a predetermined timing. A fixing device 6 for fixing the toner image on the transfer material is installed on the downstream side of the transfer material conveyance belt 3 in the conveyance direction. Examples of the transfer material conveying member include a drum-shaped transfer material conveying member and a roller-shaped transfer material conveying member in addition to the transfer material conveying belt.

  In such a configuration, the transfer material conveyed by the transfer material conveyance belt 3 is transferred with the toner image on the photosensitive drum 1 by the charge from the transfer bias roller 5 at the transfer position. Thereafter, the toner image is conveyed to the fixing device 6 by the transfer material conveying belt 3, and the toner image is fixed to the transfer material by the fixing device 6.

  The transfer material conveyance belt 3 is housed and supported in a case 7 together with belt drive rollers 4 a and 4 b and a transfer bias roller 5 for driving the transfer material conveyance belt 3, and is integrated with the case 7 to transfer material conveyance belt unit A. Is configured. The transfer material transport belt unit A is detachably set in the main body of the image forming apparatus via a support base 8 that supports the transfer material transport belt unit A.

  As shown in FIG. 2, the support base 8 has two side plates 10a and 10b, and the transfer material conveyance belt unit B is set between the side plates 10a and 10b. Specifically, a support shaft 9 is attached to each of the side plates 10a and 10b, and the case 7 of the transfer material transport belt unit A is detachably and rotatably supported with respect to the support base 8 via the support shaft 9. The

  Further, the shaft portion 11 extends between the side plates 10a and 10b so as to penetrate the side plates 10a and 10b. The shaft portion 11 is supported so as to be rotatable with respect to the side plates 10a and 10b. An operation lever 13 is attached and fixed to the end of the shaft 11 passing through the side plate 10a. A cam 12 is fixed to a portion of the shaft portion 11 located between the side plates 10a and 10b. The cam 12 transmits the rotation of the operation lever 13 to the support member 14 that supports the case 7.

  As shown in FIG. 2, the support base 8 is provided with slide rails 15a and 15b, and the support base 8 is pulled out from the apparatus main body via the slide rails 15a and 15b. Each side plate 10a (10b) of the support base 8 is provided with two positioning holes 18a and 18b (18c and 18d). These positioning holes 18a, 18b (18c, 18d) are formed by positioning pins 17a, 17b (17c) formed on the side plate 16 of the apparatus main body when the support base 8 is completely set in the apparatus main body as will be described later. , 17d).

  Next, a case where the transfer material transport belt unit A supported by the support base 8 is moved between the setting position inside the apparatus main body and the drawing position outside the apparatus main body will be described with reference to FIG.

  First, as shown in FIG. 1 and FIG. 3A, a state where the unit is set in the apparatus main body and the transfer material transport belt can transport the transfer paper will be described. In a state where the transfer material conveyance belt unit B is located at the set position of the apparatus main body together with the support base 8 that supports the transfer material conveyance belt unit B, the support member 14 is urged by the spring 25 so as to push up the case 7. As a result, the belt unit A housed and held in the case 7 is brought close to the photosensitive drum 1 and can be transferred onto the transfer material.

  At this set position, the positioning pins 17 a and 17 b provided on the front plate 16 of the apparatus main body engage with the positioning holes 18 a and 18 b provided on the front plate 10 a of the support base 8. Further, positioning pins on the apparatus main body (not shown) are also engaged with positioning holes 18c and 18d provided on the rear plate 10b of the apparatus main body. Thereby, the support base 8 and the transfer material transport belt unit A supported by the support base 8 are positioned with respect to the apparatus main body.

  When the transfer material transport belt unit A is pulled out of the apparatus main body together with the support base 8 from the set position, first, the operation lever 13 in FIG. 3A is rotated counterclockwise. As a result, the shaft portion 11 rotates and the cam 12 attached to the shaft portion 11 rotates. As the cam 12 rotates, one end of the support member 14 is lifted as shown in FIG. 3B, and the support member 14 rotates clockwise. By rotating the support member, the end of the support member 14 supporting the case 7 is lowered, and the pressing state from the support member 14 against the lower surface of the case 7 is released. As a result, the transfer material transport belt unit A supported by the support base 8 rotates downward due to its own weight and is separated from the photosensitive drum 1. By separating the photosensitive drum 1 and the transfer material conveyance belt 3 from each other, it is possible to prevent the photosensitive drum 1 and the transfer material conveyance belt 3 from being damaged due to contact during jam processing.

Thus, the transfer material conveying belt 3 can be pulled out to the outside of the apparatus main body, so that the maintainability is good.
Further, the operation lever 13 used when separating the transfer material conveyance belt 3 is also used when an operator holds the unit portion to pull out the unit portion, and the unit can be pulled out by pulling the lever.

  Further, in the image forming apparatus of the present embodiment, the transfer material conveyance unit 19 cannot be pulled out from the apparatus main body at the set position where the transfer material conveyance belt 3 is close to the photosensitive drum 1. Yes. Therefore, the transfer material conveyance belt 3 is not accidentally pulled out from the apparatus main body in a state where the transfer material conveyance belt 3 and the photoconductor 1 are in contact with each other, and a dedicated product is separately provided for damage to the photoconductor 1 associated therewith. Without any problem.

Next, the shape of the operation lever 13 which is a characteristic part of the present invention will be described.
FIG. 5 is a perspective view of the operation lever 13 of the present invention, and FIG. 6 is a perspective view of a transfer material transport unit to which the present invention is applied. As a rotation restricting means that comes into contact with the unit main body at the end opposite to the handle support portion 13b which is a joint portion with the shaft portion 11 to the handle portion 13a to which a user applies a force when pulling out the unit. Convex part 13c which is this rotation control member is provided. The effect | action by providing this convex part 13c is demonstrated using FIG. When a force F is applied in the same manner as in FIG. 4, a rotating force is applied with the point P as a fulcrum, and the end 13 d tends to be displaced in the unit direction. However, the end portion 13d cannot be displaced because of the convex portion 13c. Thereby, the bending moment concerning the axial part 11 by this displacement can be reduced.

  Further, the convex portion 13 c may also be used as a stopper for the operation lever 13. As shown in FIG. 7, stopper restraints 26a and 26b are provided as rotation range restricting members for restricting the movement range of the tip of the convex portion 13c on the surface with which the convex portion 13c on the unit main body 19 side contacts. When the operating lever 13 is rotated counterclockwise to the stopper presser 6a position, the pressing state of the transfer material transport belt 3 is released and the transport unit can be pulled out. As for the set position inside the apparatus main body, when the transport unit is pushed in and the operation lever 5 is rotated clockwise to the stopper presser 6b position, the transfer material transport belt 3 is pressed and the transport unit is set. As a result, the rotation range in which the operation lever 13 can be rotated is restricted, and the position of the operation lever 13 in a state where the transfer material conveyance belt 3 is close to the photosensitive drum 1 and in a state where it is separated from the photoconductor 1 is determined. .

  As described above, in the image forming apparatus according to this embodiment, the operation lever 13 serving as the operation lever of the conveyance belt contacting / separating mechanism and the pulling handle of the transfer material conveyance unit 19 are provided with the protrusions for preventing the deflection. It is possible to prevent deformation of the shaft portion connecting the lever and the transfer material transport unit.

  Next, the shape of the operation lever 13 of the modification 1 which can apply this embodiment is shown in FIG. In the first modification, the handle support portion 13b that connects the shaft portion 11 and the handle portion 13a has a cylindrical shape whose diameter is the maximum width of the handle portion 13a. Moreover, the unit side support part 23 which supports the axial part 11 by the unit side is provided, and the unit side support part 23 also has the column-shaped structure of the same diameter as the support part 13a. And the support part 13b and the unit side support part 23 are contacting in the circular plane centering on the axial part 11, as shown in FIG. Even if a force is applied to the handle portion 13a to pull out the unit and a bending moment acts on the shaft portion 11, the bending moment acting on the shaft portion 11 can be reduced by the drag in the contact surface R region. Further, when the unit is pulled out and jamming is finished and the unit is pushed into the apparatus main body, even if it is pushed by applying force only to the handle portion 13a, the bending moment acting on the shaft portion 11 can be reduced by the drag in the contact surface L region. .

  As described above, in the image forming apparatus according to the first modification, the shaft 11 of the lever can be prevented from being deformed not only when the unit is pulled out but also when the unit is pushed in to set the apparatus body.

  Next, FIG. 10 shows a schematic diagram of a unit in the vicinity of which the operation lever 13 is connected in Modification 2 to which the present embodiment is applicable. In the second modification, the transfer material transport unit 19 is provided with the same action as the convex portion 13c provided on the operation lever 13 in the above-described embodiment. This is provided with an extending portion 13e on the opposite side of a handle support portion 13b which is a joint portion with the shaft portion 11 from the handle portion 13a to which a user applies a force when pulling out the unit. Then, when the operation lever 13 is in the unit drawing position, a convex portion 27 as a rotation restricting member is provided on the transfer material transport unit 19 side so as to come into contact with the end of the extending portion 13e. ing. When the force F is applied to the convex portion 27 in the same manner as in FIG. 4, a rotating force is applied with the point P as a fulcrum, and the end portion of the extending portion 13 e tends to be displaced in the unit direction. However, since there is the convex portion 27, the end portion of the extending portion 13e cannot be displaced. Thereby, the bending moment concerning the axial part 11 by this displacement can be reduced.

Further, the transfer material transport unit 19 that is pulled out by pulling the operation lever 13 may include the fixing device 6 and the registration rollers 2a and 2b.
As a result, compared to a unit in which a unit having only the transfer material conveyance belt 3 is detachable from the apparatus main body, a series of transfer material conveyance paths such as the registration roller 2, the transfer material conveyance belt 3, and the fixing device 6 are aligned. It becomes easy.

As described above, in the image forming apparatus of the present embodiment, the transfer material conveyance belt 3 as a transfer material conveyance member that conveys the transfer material so as to pass the transfer position to which the toner image on the photoconductor 1 as an image carrier is transferred. And an operation lever 13 having a handle portion 13a to be gripped by an operator, a shaft portion 11 fixed to one end portion of the handle portion 13a, and the operation lever 13 rotating around the one end portion. A transfer material conveyance unit 19 that is detachable from the apparatus main body and has a contact / separation mechanism that moves the transfer material conveyance belt 3 closer to or away from the photosensitive member 1 in accordance with the rotation of the shaft portion 11. The transfer material transport unit 19 is configured to be detached from the apparatus main body by gripping the handle portion 13 a and pulling the operation lever 13 along the axial direction of the shaft portion 11. This image forming apparatus has a convex portion 13c as a rotation restricting means for restricting the rotation operation of the operation lever 13 along a virtual plane including the axis of the shaft portion 11 with the one end portion as a center. . With such a configuration, the bending moment applied to the shaft portion 11 can be reduced.
Further, the convex portion 13 c in the present embodiment is a rotation restricting member that is provided on the opposite side of the handle portion 13 a across the one end portion and contacts the outer plate of the transfer material transport unit 19. With such a configuration, the bending moment applied to the shaft portion 11 can be reduced with a simple configuration in which the operation lever 13 is provided with the convex portion 13c.
Further, a stopper restraining member 26 as a rotation range regulating member that abuts on the convex portion 13 c and regulates the rotation range of the operation lever 13 in the present embodiment is provided on the outer plate of the transfer material transport unit 19. With such a configuration, the rotation range of the operation lever 13 can be restricted without providing a new member on the operation lever 13.
In the present embodiment, the convex portion 13c is provided on the operation lever side, but it may be provided on the transfer material transport unit side. Specifically, when the operation lever 13 is provided with an extending portion 13e extending from the coupling portion between the handle portion and the shaft to the opposite side of the handle portion and the operation lever is pulled along the axial direction of the shaft portion 11. On the outer plate of the transfer material transport unit 19, a convex portion 27 as a rotation restricting member is provided so as to come into contact with the extending portion 13e. With such a configuration, the bending moment applied to the shaft portion 11 can be reduced with a simple configuration in which the convex portion 27 is provided on the outer plate of the transfer material transport unit 19.
In the image forming apparatus according to the present exemplary embodiment, the transfer material conveyance unit 19 includes the transfer conveyance belt unit A including the transfer material conveyance belt 3 and a fixing device 6 that fixes the toner image onto the transfer material onto which the toner image is transferred. Are included. With this configuration, the transfer material conveyance belt 3 and the fixing device 6 can be easily aligned.
In the image forming apparatus according to the present embodiment, the transfer material transport unit 19 is configured to include the registration roller 2. With this configuration, alignment between the transfer material conveyance belt 3 and the registration roller 2 is facilitated.

FIG. 4 is an explanatory diagram of a transfer material transport unit that is detachable from the apparatus main body. Explanatory drawing of the support stand in a transfer material conveyance unit which supports a transfer material conveyance belt unit. FIG. 3 is an explanatory diagram of a contact / separation mechanism between a photoconductor and a transfer material conveyance belt. Conventional operation lever explanatory drawing. The perspective view of the operation lever concerning this invention. The perspective view of the transfer material conveyance unit to which the operation lever concerning this invention is applied. Explanatory drawing of the operation lever concerning this invention. The front view of the operation lever concerning this invention. The shape explanatory view of modification 1 of the operation lever concerning the present invention. The shape explanatory view of modification 2 of the operation lever concerning the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photosensitive drum 2a, b Registration roller 3 Transfer material conveyance belt 4 Transfer material conveyance belt drive roller 5 Transfer bias roller 6 Fixing device 7 Transfer material conveyance belt support case 8 Transfer material conveyance belt support stand 9 Transfer material conveyance belt rotating shaft 10a, b Support base side plate 11 Operation lever rotating shaft 12 Rotating cam 13 Operation lever 14 Transfer material transport belt support case support member 15a, b Transfer bias roller 16 Side plate 17a, b, c, d of apparatus main body Positioning pins 18a, b, c, d Positioning hole 19 Transfer material transport unit 20 Developer 21 Cleaning unit 22 Charger charger 23 Unit side support unit 25 Spring 26 Stopper restraint 27 Unit side lever rotation restricting member

Claims (6)

A transfer material conveying member for conveying the transfer material so as to pass through a transfer position where the toner image on the image carrier is transferred;
An operating lever having a handle portion gripped by an operator;
A shaft fixed to one end of the handle;
An apparatus main body having a contact / separation mechanism for moving the transfer material conveying member closer to or away from the image carrier according to the rotation of the shaft generated by rotating the operation lever around the one end. A transfer material transport unit
In the image forming apparatus configured such that the transfer material transport unit is detached from the apparatus main body by an operator gripping the grip part and pulling the operation lever along the axial direction of the shaft part.
An image forming apparatus comprising: a rotation restricting unit that restricts a rotation operation of the operation lever along a virtual plane including the axis of the shaft portion with the one end portion as a center. The image forming apparatus according to claim 1.
An image forming apparatus, wherein the rotation restricting means is constituted by a rotation restricting member that is provided on the opposite side of the handle portion with the one end portion interposed therebetween and that contacts the outer plate of the transfer material transport unit. The image forming apparatus according to claim 2.
An image forming apparatus comprising: a rotation range regulating member that abuts on the rotation regulating member and regulates a rotation range of the operation lever on the outer plate. The image forming apparatus according to claim 1.
The operating lever is provided with an extending portion extending from the one end portion to the opposite side of the handle portion,
A rotation restricting member provided on the outer plate of the transfer material transport unit so that the rotation restricting means comes into contact with the extension when the operation lever is pulled along the axial direction of the shaft. An image forming apparatus comprising: The image forming apparatus according to claim 1, 2, 3, or 4.
The transfer material transport unit includes: a transfer device having the transfer material transport member; and a fixing device for fixing the toner image onto the transfer material onto which the toner image has been transferred. The image forming apparatus according to claim 5.
The image forming apparatus, wherein the transfer material transport unit includes a registration roller.

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