JP2013010592A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus which is easy-to-use for a user.SOLUTION: The image forming apparatus includes: a conveyance roller 24 that is opposed to an opening 2A of a body housing 2; a rear cover 25 that opens and closes the opening 2A and has a guide rib 25B guiding paper S, while curving it upward, in its closing state; and a rear chute 26 that supports a driven roller 24B, and can rock between a contact position where the driven roller 24B is brought into contact with a driving roller 24A, and a separation position where the driven roller 24B is separated from the driving roller 24A. The rear cover 25 has an extension part 25D extending to a lower side than a rocking shaft 25A in the closing state, and is provided so that the paper S fed from the conveyance roller 24 may be placed thereon in its opening state. The rear chute 26 has a regulation part 27 on which the extension part 25D of the rear cover 25 in the opening state abuts, thereby regulating posture of the rear cover 25 at least in width of the paper S placed on the rear cover 25.

Description

  The present invention relates to an image forming apparatus including a cover that opens and closes an opening of an apparatus main body.

  An image forming apparatus such as a printer is provided with a cover that opens and closes an opening of the apparatus main body by swinging with respect to the apparatus main body, and the paper carried out from the image forming unit in the closed state is formed on the cover. There has been known one provided with a guide that guides while curving toward a paper discharge tray provided above the section (see, for example, Patent Document 1). In addition, in the image forming apparatus as described above, a configuration is also known in which the upper surface of the opened cover is used as a paper discharge tray for paper discharged straight from the apparatus main body.

JP 2010-202402 A

  By the way, like the image forming apparatus disclosed in Patent Document 1 (see FIG. 8), when a gap is formed between the lower end of the opened cover and the apparatus main body, the cover is placed on the upper surface of the cover. There is a possibility that the paper may fall through the gap, which may make it difficult for the user to use.

  The present invention has been made in view of the above background, and an object thereof is to provide an image forming apparatus that is easy for a user to use.

In order to achieve the above-described object, the image forming apparatus of the present invention is provided to be opposed to the apparatus main body, the opening of the apparatus main body, a pair of conveyance rollers for feeding the recording sheet, and the apparatus main body to be swingable. A cover having a guide portion for guiding the recording sheet sent from the pair of conveying rollers in a closed state while curving the recording sheet toward the upper side of the pair of conveying rollers, and one of the pair of conveying rollers And a support member that can swing between a contact position where the one roller is brought into contact with the other roller and a separation position where the one roller is separated from the other roller.
The cover has an extending portion extending downward from the swing shaft in the closed state, and is provided so that the recording sheet fed from the pair of conveying rollers is placed in the open state. .
The support member has a regulating portion that regulates the posture of the cover by contacting the extended portion of the cover in the open state, at least within the width of the recording sheet placed on the cover.

  According to such a configuration, in the opened state, the cover on which the recording sheet sent from the pair of conveying rollers is placed has an extension portion at least within the width of the recording sheet placed on the cover. Since the contact portion is in contact with the restricting portion of the support member, a gap through which the recording sheet can pass is not formed between the cover and the support member. Thereby, the recording sheet placed on the cover can be prevented from dropping.

Even if the recording sheet is jammed between a pair of conveying rollers, the nip between one roller and the other roller is released by opening the cover and swinging the support member from the contact position to the separation position. Therefore, the jammed recording sheet can be easily processed.
As described above, the image forming apparatus can be easily used by the user.

  In the above-described image forming apparatus, the restricting portion includes a first contact portion with which the extension portion contacts at the contact position, and a second contact portion with which the extension portion contacts at the separation position. The distance from the contact portion to the swing center of the support member is smaller than the distance from the first contact portion to the swing center, and the first contact portion to the second contact portion is a continuous surface. It can be set as the structure which has.

  According to such a configuration, when the jam processing is performed, the support member is swung from the contact position to the separated position, so that the cover is further opened in conjunction with the support member, so that the jam processing can be performed more easily. Can do.

  In the image forming apparatus according to the aspect of the invention, the restricting portion includes a first abutting portion with which the extending portion abuts at the contact position, and a second abutting portion with which the extending portion abuts at the separated position. A configuration in which the first contact portion to the second contact portion have a curved surface centered on the swing center of the support member may be employed.

  According to such a configuration, when the jam processing is performed, even if the support member is swung from the contact position to the separation position, the cover does not swing, particularly in the closing direction, so that the jam processing can be easily performed. Can do.

  Further, since the force transmitted from the extending portion to the restricting portion is always directed to the swing center of the support member when the extending portion of the cover abuts on the restricting portion and after the contact, the support member Therefore, unnecessary force, in particular, force for swinging the support member does not act. Therefore, the posture of the support member and the cover can be stabilized even when the support member is in any position of the contact position and the separation position. In addition, this makes it possible to stably bring the pair of conveying rollers into contact with each other particularly when the support member is in the contact position. can do.

  In the image forming apparatus in which the distance from the second contact portion to the swing center is smaller than the distance from the first contact portion to the swing center, the normal line of the first contact portion is the swing of the support member. It is preferable to be configured to pass through the moving center.

  According to such a configuration, similarly to the above, the force transmitted from the extending portion to the restricting portion when and after the extending portion of the cover contacts the restricting portion (first abutting portion). Is directed toward the center of swinging of the support member, so that a force for swinging the support member does not act. Accordingly, the postures of the support member and the cover can be stabilized, and the pair of conveying rollers can be stably brought into contact with each other, so that the recording sheet can be stably conveyed.

  According to the present invention, it is possible to prevent the recording sheet placed on the cover from dropping or to easily perform jam processing, so that the image forming apparatus can be easily used by the user.

1 is a diagram illustrating a schematic configuration of a laser printer as an example of an image forming apparatus according to a first embodiment of the present invention. It is an enlarged view which shows the state which opened the rear cover in the laser printer which concerns on 1st Embodiment. It is a perspective view which shows the contact state of a rear cover and a control part. It is an enlarged view which shows the state which rock | fluctuated the rear chute | shoot which concerns on 1st Embodiment to the separation position. It is an enlarged view which shows the state which closed the rear cover in the laser printer which concerns on 2nd Embodiment. It is an enlarged view which shows the state which opened the rear cover. It is an enlarged view which shows the state which rock | fluctuated the rear chute | shoot which concerns on 2nd Embodiment to the separation position.

[First Embodiment]
Next, a first embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the following description, first, a schematic configuration of the laser printer 1 as an example of the image forming apparatus according to the embodiment will be briefly described, and then the laser printer 1 (around the rear cover 25) according to the characteristic part of the present invention will be described. A detailed configuration will be described.

  In the following description, the direction will be described with reference to the user who uses the laser printer 1. That is, the right side in FIG. 1 is “front”, the left side is “rear”, the front side is “left”, and the back side is “right”. Also, the vertical direction in FIG.

<Schematic configuration of laser printer>
As shown in FIG. 1, a laser printer 1 includes a main body housing 2 as an example of an apparatus main body, a paper feeding unit 3 that supplies paper S as an example of a recording sheet, an exposure device 4, and a paper S. The apparatus mainly includes a process cartridge 5 that transfers a toner image (developer image) and a fixing device 8 that thermally fixes the toner image on the paper S.

  The paper feed unit 3 is provided at a lower portion in the main body housing 2 and mainly includes a paper feed tray 31, a paper pressing plate 32, and a paper feed mechanism 33. The paper S (for example, plain paper) accommodated in the paper feed tray 31 is moved upward by the paper pressing plate 32, and the process cartridge 5 (between the photosensitive drum 61 and the transfer roller 63) is fed by the paper feed mechanism 33. Supplied towards

  The exposure device 4 is disposed in the upper part of the main body housing 2 and includes a laser light emitting unit, a polygon mirror, a lens, a reflecting mirror, and the like (not shown). In this exposure device 4, the surface of the photosensitive drum 61 is exposed by scanning the surface of the photosensitive drum 61 at high speed with laser light (see the chain line) based on the image data emitted from the laser light emitting unit.

  The process cartridge 5 is disposed below the exposure apparatus 4 and is detachably mounted on the main body housing 2 through an opening formed when the front cover 21 provided on the main body housing 2 is opened. Yes. The process cartridge 5 includes a drum unit 6 and a developing unit 7.

  The drum unit 6 mainly includes a photosensitive drum 61, a charger 62, and a transfer roller 63. The developing unit 7 is configured to be detachably attached to the drum unit 6, and includes a developing roller 71, a supply roller 72, a layer thickness regulating blade 73, and a toner that contains toner (developer). The housing part 74 is mainly provided.

  In the process cartridge 5, the surface of the photosensitive drum 61 is uniformly charged by the charger 62 and then exposed by high-speed scanning of the laser light from the exposure device 4, whereby an image is formed on the photosensitive drum 61. An electrostatic latent image based on the data is formed. Further, the toner in the toner container 74 is supplied to the developing roller 71 via the supply roller 72 and enters between the developing roller 71 and the layer thickness regulating blade 73 to form a thin layer of a certain thickness on the developing roller 71. It is carried on.

  The toner carried on the developing roller 71 is supplied from the developing roller 71 to the electrostatic latent image formed on the photosensitive drum 61. As a result, the electrostatic latent image is visualized and a toner image is formed on the photosensitive drum 61. Thereafter, the sheet S is conveyed between the photosensitive drum 61 and the transfer roller 63 so that the toner image on the photosensitive drum 61 is transferred onto the sheet S.

  The fixing device 8 is disposed behind the process cartridge 5, and mainly includes a heating roller 81 and a pressure roller 82 disposed so as to face the heating roller 81 and press the heating roller 81. In the fixing device 8, the toner image transferred onto the paper S is thermally fixed while the paper S passes between the heating roller 81 and the pressure roller 82. The paper S on which the toner image has been thermally fixed is discharged onto a paper discharge tray 22 provided on the upper portion of the main body housing 2 by a transport roller 24 and a paper discharge roller 23.

<Detailed configuration of laser printer>
The laser printer 1 includes a pair of conveying rollers 24, a rear cover 25 as an example of a cover, and a rear chute 26 as an example of a support member as a configuration related to the characteristic part of the present invention.

  The conveyance roller 24 is a roller that conveys (sends) the sheet S carried out from the fixing device 8 toward the outside of the main body housing 2, and faces the opening 2 </ b> A of the main body housing 2 behind the fixing device 8. (Between the fixing device 8 and the opening 2A). In the present embodiment, a plurality of pairs of transport rollers 24 are provided side by side in the left-right direction (see FIG. 3).

  Each pair of transport rollers 24 is arranged on the upper side, and a driving roller 24A (an example of the other roller) that is rotationally driven by a driving force transmitted from a motor (not shown) provided in the main body housing 2. And a driven roller 24B (an example of one roller) that is disposed on the lower side and is driven to rotate by a driving roller 24A.

  The rear cover 25 is provided so as to be swingable with respect to the main body housing 2 with the swing shaft 25A as a swing center, and the opening 2A provided at the rear portion of the main body housing 2 is opened and closed by the swing. The rear cover 25 is a guide rib as an example of a guide portion that guides the sheet S fed from the transport roller 24 in a closed state while curving it toward the paper discharge roller 23 and the paper discharge tray 22 above the transport roller 24. 25B.

  As shown in FIG. 2, the rear cover 25 is provided so that the paper S sent out from the transport roller 24 is placed in the opened state. In other words, when the rear cover 25 is opened, the sheet S (for example, a postcard) discharged from the inside of the main body housing 2 through the opening 2 </ b> A is placed on the rear cover 25. .

Returning to FIG. 1, the rear cover 25 mainly includes the guide rib 25 </ b> B, the cover portion 25 </ b> C, and the extending portion 25 </ b> D.
A plurality of guide ribs 25B (only one is shown in the figure) are provided on the inner surface of the cover portion 25C so as to be lined up in the left-right direction.

  The cover portion 25C is a portion that covers the opening 2A through which the paper S can pass in the closed state, and is formed with a width that is substantially the same as the width of the opening 2A (the interval between the edges of the opening 2A facing in the left-right direction). ing. In other words, as shown in FIG. 3, the width L1 (length in the left-right direction) of the cover portion 25C (rear cover 25) is the paper S, more specifically, the maximum size paper on which the laser printer 1 can form an image. It is formed larger than the width W of S.

  As shown in FIG. 1, the extended portion 25D is a portion extending downward from the swing shaft 25A in the closed state, and constitutes a lower portion of the cover portion 25C and has a lower end portion thereof. 25E is bent toward the inside (front) of the main body housing 2. As shown in FIG. 2, the lower end portion 25E of the extending portion 25D comes into contact with a later-described restricting portion 27 of the rear chute 26 when the rear cover 25 is opened.

  The rear chute 26 is provided behind the fixing device 8 and has a guide surface 26B that can guide the sheet S carried out of the fixing device 8 toward the conveying roller 24 (between the driving roller 24A and the driven roller 24B). Have. The rear chute 26 is formed as a separate component from the main body housing 2 and rotatably supports the driven roller 24B of the pair of conveying rollers 24 including the driving roller 24A and the driven roller 24B.

  As shown in FIGS. 2 and 4, the rear chute 26 is provided to be swingable with respect to the main body housing 2 with the swing shaft 26 </ b> A as the swing center. More specifically, the rear chute 26 has a contact position where the driven roller 24B is brought into contact with the driving roller 24A supported by the main body housing 2 as shown in FIG. 2, and the driven roller 24B shown in FIG. 4 is separated from the driving roller 24A. It is supported so that it can swing between the separated positions.

  As a result, even when the paper S is jammed between the transport rollers 24, the nip between the driving roller 24A and the driven roller 24B is opened by opening the rear cover 25 and swinging the rear chute 26 from the contact position to the separation position. Therefore, it is possible to easily process the jammed paper S (jam processing).

  In addition, the rear chute 26 has a restricting portion 27 that restricts the posture of the rear cover 25 when opened by the lower end 25E of the extended portion 25D of the opened rear cover 25 coming into contact with the lower end of the rear portion. doing. More specifically, the restricting portion 27 includes a first abutting portion 27A with which the lower end portion 25E of the extending portion 25D abuts at the contact position shown in FIG. 2, and a lower end portion 25E of the extending portion 25D at the separated position shown in FIG. Has a second abutting portion 27B that abuts, and the first abutting portion 27A to the second abutting portion 27B have a substantially arcuate curved surface in a side view.

  More specifically, in the restricting portion 27, the distance D2 from the second contact portion 27B to the swing shaft 26A (swing center) is smaller than the distance D1 from the first contact portion 27A to the swing center. The curved surface shape gradually approaches the swing shaft 26A from the first contact portion 27A toward the second contact portion 27B.

  As shown in FIG. 3, in the present embodiment, the width L2 (length in the left-right direction) of the restricting portion 27 is the width of the paper S placed on the rear cover 25 in the opened state (discharged from the opening 2A). The width dimension is substantially the same as W, and is smaller than the width L1 of the rear cover 25 (the lower end 25E of the extension 25D). The restricting portion 27 and the lower end portion 25E of the extending portion 25D are formed so as to be able to contact each other in the substantially entire range in the left-right direction within the width W of the paper S.

  As a result, the sheet S on which an image can be formed by the laser printer 1 can pass between the opened rear cover 25 (the lower end 25E of the extending portion 25D) and the rear chute 26 (the restricting portion 27). Since no gap is formed, the paper S placed on the rear cover 25 can be prevented from falling.

  Further, the restricting portion 27 has a curved surface shape that gradually approaches the swing shaft 26A from the first abutting portion 27A toward the second abutting portion 27B, so that the rear chute 26 is shown in FIG. When the rear cover 25 is swung from the contact position to the separated position shown in FIG. 4, the rear cover 25 is swung so as to be further opened from the posture shown by the two-dot chain line in FIG. Thereby, since the opening 2A is exposed to the outside more widely, the user's hand is easily put in, so that the jam processing can be performed more easily.

  As shown in FIG. 2, in the present embodiment, the restricting portion 27 is formed so that the normal line L of the first contact portion 27A passes through the swing shaft 26A (swing center) of the rear chute 26. Yes. Thereby, when the rear cover 25 is opened and the lower end portion 25E of the extending portion 25D comes into contact with the first contact portion 27A, and after the contact, the first contact portion comes from the lower end portion 25E of the extension portion 25D. Since the force transmitted to the portion 27A is always directed to the swing center of the rear chute 26, unnecessary force, in particular, a force for swinging the rear chute 26 does not act on the rear chute 26. Yes.

  Therefore, when the rear chute 26 is in the contact position, the posture of the rear chute 26 and the rear cover 25 supported by the rear chute 26 can be stabilized. In addition, since the transport roller 24 can be stably brought into contact with the sheet S, it is possible to stably transport the paper S even in a configuration in which the transport roller 24 can come in contact with and separate from.

  According to the present embodiment described above, the paper S placed on the rear cover 25 can be prevented from dropping or jammed easily, so that the laser printer 1 is easy to use for the user. be able to.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 5, the restricting portion 28 of the rear chute 26 according to the present embodiment is configured such that the lower end portion 25 </ b> E of the extending portion 25 </ b> D comes into contact with the extending portion 25 </ b> D at the spaced position. Up to the second abutting portion 28B with which the lower end portion 25E abuts is a curved surface having a circular arc shape when viewed from the side with the oscillating shaft 26A (swaying center) as a center. That is, in the restricting portion 28, the distance D3 from the first contact portion 28A to the swing center is equal to the distance D4 from the second contact portion 28B to the swing center, and further, from the first contact portion 28A. The distance from each position to the second abutting portion 28B to the swing center is equal to the distance D3 (= D4).

  According to such a configuration, when the jam processing is performed, the rear cover 25 does not swing even when the rear chute 26 is swung from the contact position illustrated in FIG. 6 to the separated position illustrated in FIG. Therefore, the jam processing can be easily performed.

  Further, according to the configuration of the present embodiment, the normal line (not shown) passes through the swing center of the rear chute 26 in both the first contact part 28A and the second contact part 28B. The force transmitted from the lower end 25E of the extending portion 25D to the restricting portion 28 is always the rear chute when the lower end 25E of the extending portion 25D is in contact with the restricting portion 28 and after the opening. 26 is directed toward the swing center.

  As a result, no force acts on the rear chute 26 to swing the rear chute 26 when the rear chute 26 is in the contact position or the separated position. The posture can be stabilized. Further, when the rear chute 26 is in the contact position, the transport roller 24 can be stably contacted as in the case of the first embodiment described above, so that the sheet S can be transported stably. Become.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment. About a concrete structure, it can change suitably in the range which does not deviate from the meaning of this invention.

  In the above-described embodiment, the extending portion 25D and the restricting portion 27 are configured to abut on the entire range within the width W of the maximum size paper S on which the laser printer 1 can form an image. Is not limited to this. That is, the range in which the extension portion and the restriction portion contact each other is a range in which the recording sheet placed on the cover can be prevented from dropping (a gap through which the recording sheet can pass between the extension portion and the restriction portion). For example, it may be within the range of the width of the minimum size recording sheet capable of image formation. As a matter of course, the extending portion and the restricting portion may be in contact with each other in a range larger than the width of the maximum size recording sheet capable of image formation.

  Moreover, in the said embodiment, although extension part 25D and the control part 27 were contact | abutting continuously in the left-right direction (width direction) (refer FIG. 3), this invention is not limited to this, For example, You may be comprised so that it may contact | abut intermittently in the width direction. That is, in the present invention, there is no problem even if a gap having a width smaller than the width of the minimum size recording sheet capable of image formation is formed between the abutting extension portion and the regulating portion.

  In the embodiment, the rear cover 25 provided at the rear part of the main body housing 2 (apparatus main body) is exemplified as the cover, but the present invention is not limited to this, and is provided, for example, at the front part or the left and right of the apparatus main body. It may be a cover.

  In the embodiment, the laser printer 1 that exposes the photosensitive drum 61 (photosensitive member) with laser light is exemplified as the image forming apparatus, but the present invention is not limited to this. For example, an electrophotographic printer that exposes a photoreceptor with LED light, an ink jet printer, or a thermal printer may be used. The image forming apparatus is not limited to a printer, and may be, for example, a copier or a multi-function machine including a document reading apparatus such as a flat bed scanner. Furthermore, the image forming apparatus may be capable of forming not only a monochrome image but also a color image.

  In the embodiment, the paper S such as plain paper or postcard is exemplified as the recording sheet. However, the present invention is not limited to this, and may be, for example, an OHP sheet.

DESCRIPTION OF SYMBOLS 1 Laser printer 2 Main body housing | casing 2A Opening 24 Conveyance roller 24A Drive roller 24B Follower roller 25 Rear cover 25A Oscillation shaft 25B Guide rib 25D Extension part 26 Rear chute 26A Oscillation axis 27 Restriction part 27A 1st contact part 27B 2nd Contact part S Paper

Claims (4)

The device body;
A pair of conveying rollers provided facing the opening of the apparatus main body, and for feeding out a recording sheet;
A guide unit that is swingably provided in the apparatus main body, opens and closes the opening, and guides the recording sheet fed from the pair of conveying rollers in a closed state while curving the recording sheet toward the upper side of the pair of conveying rollers. A cover having
Swing between a contact position for supporting one roller of the pair of transport rollers and bringing the one roller into contact with the other roller, and a separation position for separating the one roller from the other roller A possible support member,
The cover has an extending portion extending downward from the swing shaft in the closed state, and is provided so that the recording sheet fed from the pair of conveying rollers is placed in the open state. ,
The support member has a restricting portion that restricts the posture of the cover by contacting the extended portion of the cover in an open state, at least within a width of the recording sheet placed on the cover. Image forming apparatus. The regulation part is
A first abutting portion with which the extending portion abuts at the contact position; and a second abutting portion with which the extending portion abuts at the separated position;
The distance from the second contact portion to the swing center of the support member is smaller than the distance from the first contact portion to the swing center, and from the first contact portion to the second contact. The image forming apparatus according to claim 1, wherein the surface is a continuous surface. The regulation part is
A first abutting portion with which the extending portion abuts at the contact position; and a second abutting portion with which the extending portion abuts at the separated position;
The image forming apparatus according to claim 1, wherein the first contact portion to the second contact portion have a curved surface centered on a swing center of the support member.   The image forming apparatus according to claim 2, wherein a normal line of the first contact portion passes through a swing center of the support member.

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