JP7296049B2 - Sheet conveying device and image forming device - Google Patents

Description

The present invention relates to a sheet conveying device and an image forming apparatus.

Conventionally, an opening/closing member having a first conveying roller and capable of opening and closing with respect to an apparatus main body, and a swinging member having a second conveying roller in contact with the first conveying roller and held swingably by the opening/closing member is known.

Japanese Patent Application Laid-Open No. 2002-100003 describes a sheet conveying device in which a fixing device provided in an image forming apparatus positions a rocking member and an opening/closing member.

However, in Japanese Patent Application Laid-Open No. 2002-200011, there is a possibility that the contact pressure between the first conveying roller and the second conveying roller may vary, and the sheet conveying force may vary.

In order to solve the above-described problems, the present invention has a first conveying roller, an opening and closing member that can be opened and closed with respect to an apparatus main body, and a second conveying roller that contacts the first conveying roller, and a swinging member that is swingably held by an opening/closing member, wherein the swinging member is held by a plurality of holding portions on the opening/closing member, and is rotated in the axial direction of the first conveying roller. is the X direction, the front-rear direction of the device orthogonal to the X direction is the Y direction, and the direction orthogonal to both the X direction and the Y direction is the Z direction, one of the plurality of holding portions is the A positioning and holding portion that positions and holds the swinging member in the Y direction with respect to the opening and closing member, the positioning and holding portion is a holding projection that is inserted into a hole to be held, and the The length in the Z direction is longer than the length in the Z direction of the holding projection, and the rocking member is held by the opening/closing member so as to be movable within a predetermined range in the Z direction with respect to the opening/closing member. It is characterized by

According to the present invention, variations in sheet conveying force can be suppressed.

1 is a schematic configuration diagram of a printer according to one embodiment; FIG. FIG. 2 is an enlarged explanatory view showing an enlarged configuration of a photoreceptor and its surroundings; FIG. 4 is an explanatory diagram of the configuration of a fixing path and a discharge reversing path; FIG. 10 is an explanatory diagram of the position of the paper P when jamming a jam that occurred when paper was discharged; FIG. 10 is an explanatory diagram of the position of the paper P when jamming a jam that occurs when reversing; FIG. 3 is an exploded perspective cross-sectional view showing a fixing device, a swing guide portion, and a rear door; FIG. 3 is an exploded perspective view of the main parts of the vicinity of the swing guide portion as viewed from above; The figure explaining the holding structure to the rear cover of a rocking|swiveling guide part. The figure which shows the state with which the rocking|swiveling guide part was hold|maintained at the rear door. FIG. 10 is an enlarged view of broken line H in FIG. 9 ; FIG. 4 is a cross-sectional perspective view of a main part showing how a swing guide positioning projection of a swing guide portion is fitted into a positioning groove on the device main body side of the fixing device.

An embodiment of an electrophotographic printer (hereinafter referred to as a printer 100) will be described below as an image forming apparatus equipped with a sheet conveying device having a discharge reversing path to which the present invention is applied.
First, the basic configuration of the printer 100 according to the embodiment will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram of a printer 100 according to the present embodiment, and FIG. 2 is an enlarged explanatory diagram showing the photoreceptor 1 of FIG. 1 and its peripheral configuration.

As shown in FIG. 1, the printer 100 includes a photoreceptor 1 as a latent image carrier, and a paper feed cassette 21 as a sheet storage unit detachably attached to a main housing 90 . Inside the paper feed cassette 21, a plurality of sheets P as sheet materials are stacked on a bottom plate 24 and accommodated.

The paper P in the paper feed cassette 21 is sent out from the paper feed cassette 21 by the rotational drive of the feed roller 22, passes through the separation nip between the feed roller 22 and the separation roller 23, and enters the paper feed path 20. up to. After that, the sheet is nipped in the conveying nip of the sheet feed path conveying roller pair 25 and conveyed in the sheet feed path 20 from the upstream side to the downstream side in the conveying direction. A registration roller pair 11 is arranged near the end of the paper feed path 20 . With the leading edge of the paper P abutting against the registration nip of the registration roller pair 11, the paper feed path transport roller pair 25 stops, and the transport of the paper P is temporarily stopped. The skew of the paper P is corrected at the time of the butting.

After that, the registration roller pair 11 starts rotating at a timing at which the paper P can be superimposed on the toner image on the surface of the photosensitive member 1 at a transfer nip, which will be described later, and feeds the paper P toward the transfer nip. At this time, the paper P is sandwiched by the paper feed path transport roller pair 25, and the paper feed path transport roller pair 25 starts rotating at the same time as the registration roller pair 11, and the transport of the paper P, which has been temporarily suspended, is started. to resume.

Further, the main body housing 90 of the printer 100 holds the manual paper feeding unit 26 including the manual paper feeding tray 27 , the manual paper feeding roller 28 and the separation pad 29 . The paper P manually fed to the manual feed tray 27 of the manual feed unit 26 is sent out from the manual feed tray 27 by the rotational drive of the manual feed roller 28 . Then, after passing through the separation nip due to the contact between the manual feed roller 28 and the separation pad 29 , the sheet enters the region on the upstream side of the registration roller pair 11 in the paper feed path 20 . After that, like the paper P sent out from the paper feed cassette 21, the paper passes through the pair of registration rollers 11 and is sent to the transfer nip.

As shown in the enlarged explanatory view of FIG. 2, around a drum-shaped photoreceptor 1 rotated clockwise in FIG. A device 7, a developing device 8, and a transfer roller 10 are provided.
A charging roller 4 having a conductive rubber roller portion on its surface rotates while being in contact with the photoreceptor 1 to form a charging nip. A charging bias output from a power source is applied to the charging roller 4 . Accordingly, in the charging nip, discharge occurs in a minute gap between the surface of the photoreceptor 1 and the surface of the charging roller 4, so that the surface of the photoreceptor 1 is uniformly charged.

The latent image writing device 7 has an LED array, and irradiates the uniformly charged surface of the photosensitive member 1 with LED light. Of the uniformly charged background portion of the photoreceptor 1, the potential of the area irradiated with light is attenuated by this light irradiation. Thereby, an electrostatic latent image is formed on the surface of the photoreceptor 1 .
The electrostatic latent image becomes a visible image (toner image) in a developing area facing the developing device 8 as the photosensitive member 1 is driven to rotate.

The developing device 8 has a circulatory transport section and a developing section. The circulating and conveying portion accommodates developer containing toner and magnetic carrier. The circulation transport section has a first screw 8b that supplies the developer to the developing roller 8a and a second screw 8c that is located directly below the first screw 8b and collects the developer from the developing roller 8a. It also has an inclined screw 8d for transferring the developer from the second screw 8c to the first screw 8b.
The developing roller 8a, the first screw 8b, and the second screw 8c are arranged parallel to each other. In contrast, the tilting screw 8d is arranged in a position tilted from them.

The first screw 8b conveys the developer from the back side to the front side in the direction orthogonal to the plane of FIG. 2 as it is driven to rotate. At this time, a portion of the developer is supplied to the developing roller 8a arranged to face each other.
Then, the developer conveyed by the first screw 8b to the vicinity of the front end in the direction perpendicular to the plane of FIG. 2 is dropped onto the second screw 8c.

While receiving the used developer from the developing roller 8a, the second screw 8c conveys the received developer from the back side to the front side in the direction orthogonal to the plane of FIG. 2 as it is driven to rotate. .
The developer conveyed by the second screw 8c to the vicinity of the front end in the direction orthogonal to the plane of FIG. 2 is passed to the inclined screw 8d.
The developer delivered to the inclined screw 8d is conveyed from the near side to the far side in the direction perpendicular to the plane of FIG. Near the end of the side, it is delivered to the first screw 8b.

The developing roller 8a of the developing section has a rotatable developing sleeve made of a cylindrical non-magnetic member and a magnet roller arranged in the sleeve so as not to rotate together with the developing sleeve.
Part of the developer supplied to the surface of the developing sleeve by the first screw 8b is carried on the surface of the developing sleeve by the magnetic force generated by the magnet roller.
The layer thickness of the developer carried on the surface of the developing sleeve is regulated when the developing agent passes through the facing position between the sleeve and the doctor grade while moving on the surface of the developing sleeve. After that, the developer whose layer thickness is regulated moves on the surface of the developing sleeve while rubbing against the surface of the photoreceptor 1 in the developing region facing the photoreceptor 1 .

A development bias having the same polarity as the toner in the developer and the potential of the background of the photosensitive member 1 is applied to the development sleeve. The absolute value of this developing bias is larger than the absolute value of the latent image potential and smaller than the absolute value of the background potential. Therefore, in the development area, a developing potential (potential difference) acts between the electrostatic latent image on the photosensitive member 1 and the developing sleeve to electrostatically move the toner from the sleeve side to the latent image side.
On the other hand, a skin potential (potential difference) acts between the skin portion of the photoreceptor 1 and the developing sleeve to electrostatically move the toner from the skin portion side to the sleeve side. As a result, toner adheres to the electrostatic latent image on the photoreceptor 1 in the development area, and the electrostatic latent image is developed.

The developer that has passed through the developing area enters the opposing area between the developing sleeve and the second screw 8c as the developing sleeve rotates. In this facing area, a repelling magnetic field is formed by two magnetic poles of the same polarity among the plurality of magnetic poles provided on the magnet roller.
The developer that has entered the opposing area is separated from the surface of the developing sleeve by the action of the repelling magnetic field and collected by the second screw 8c.

The developer collected by the second screw 8c is conveyed to the inclined screw 8d. Since the collected developer contributes to the development in the development area, the toner concentration is lowered.
Further, the developing device 8 is provided with a toner concentration sensor for detecting the toner concentration of the developer conveyed by the inclined screw 8d.
The control unit 80 shown in FIG. 1 outputs a replenishment operation signal for replenishing toner from the toner cartridge 9 to the developer conveyed by the inclined screw 8d as necessary based on the detection result of the toner density sensor. do.

As shown in FIGS. 1 and 2, a toner cartridge 9 is arranged above the developing device 8 .
The toner cartridge 9 feeds the toner contained therein toward the toner supply member 9c by means of an agitator 9b fixed to a rotating shaft member 9a. The toner replenishing member 9c is rotationally driven in response to a replenishment operation signal output from the control unit 80, thereby replenishing the inclined screw 8d of the developing device 8 with an amount of toner corresponding to the rotational drive amount.

As the photoreceptor 1 rotates, the toner image formed on the photoreceptor 1 by the developing device 8 enters a transfer nip where the photoreceptor 1 abuts a transfer roller 10 as a transfer means. A transfer bias having a polarity opposite to the latent image potential of the photosensitive member 1 is applied to the transfer roller 10, thereby forming a transfer electric field in the transfer nip.

As described above, the registration roller pair 11 feeds the sheet P toward the transfer nip at such timing that the toner image on the photoreceptor 1 can be superimposed on the sheet P within the transfer nip. Then, the toner image on the photoreceptor 1 is transferred to the paper P, which is in close contact with the toner image at the transfer nip, due to the action of the transfer electric field and the nip pressure.

Transfer residual toner that has not been transferred onto the paper P adheres to the surface of the photoreceptor 1 after passing through the transfer nip. After the transfer residual toner is scraped off from the surface of the photoreceptor 1 by the cleaning blade 2 in contact with the photoreceptor 1, the collection screw 3 rotates to send the toner out of the unit casing. The transfer residual toner discharged from the unit casing is sent to the waste toner bottle.

The surface of the photoreceptor 1 cleaned by the cleaning blade 2 is neutralized by the neutralizer, and then uniformly charged again by the charging roller 4 .
To the charging roller 4 in contact with the surface of the photoreceptor 1, foreign matters such as toner additives and toner that has not been completely removed by the cleaning blade 2 adhere. After being transferred to the cleaning roller 5 in contact with the charging roller 4 , the foreign matter is scraped off from the surface of the cleaning roller 5 by the scraper 6 in contact with the cleaning roller 5 . The scraped foreign matter falls on the recovery screw 3 below the scraper 6. - 特許庁

After passing through the transfer nip where the photoreceptor 1 and the transfer roller 10 are in contact with each other, the paper P is sent to the fixing device 44 shown in FIG.
The fixing device 44 forms a fixing nip by contact between a fixing roller 44a containing a heat source such as a halogen lamp and a pressure roller 44b pressed against the fixing roller 44a.
A toner image is fixed on the surface of the paper P sandwiched between the fixing nips by the action of heat and pressure, and the paper P is conveyed downstream.

In FIG. 1, in the printer 100 of the present embodiment, the paper P is placed outside the body housing 90 in the sheet discharge direction and in the upper stack portion of the body housing 90 downstream of the fixing device 44 in the paper transport direction. 91, and a reversing path 56 for reversing (switching back) the sheet P and conveying it to the reversing and re-feeding path 60. A sheet ejection reversing path 50 is arranged. The paper ejection path 55 has a first paper ejection path 55a, a second paper ejection path 55b, and a third paper ejection path 55c. The reversing path 56 has a first reversing path 56a, a second reversing path 56b, and a third reversing path 56c. A switching claw 54 is rotatably provided between the second paper discharge path 55b and the third paper discharge path 55c.

In FIG. 1, the printer 100 of the present embodiment can switch between a single-sided mode in which an image is formed on only one side of the paper P and a double-sided mode in which images are formed on both sides of the paper P.
When an image is formed on one side of the paper P in the single-sided mode, or when images are already formed on both sides of the paper P in the double-sided mode, the first paper discharge path 55a on the downstream side of the fixing device 44 in the paper conveying direction, The sheet is conveyed through the sheet discharge path 55 consisting of the second sheet discharge path 55b and the third sheet discharge path 55c. Then, the paper P is passed between the paper ejection roller 53a rotating in the direction of ejecting the paper P from the main body housing 90 and the paper ejection roller 53b facing the paper ejection roller 53a, and the main body housing 90 in the sheet paper ejection direction. The paper is discharged outside and onto the stack section 91 at the top of the main body housing 90 .
At this time, the switching claw 54 provided between the second paper discharge path 55b and the third paper discharge path 55c is rotated in the direction in which the paper P is guided to the third paper discharge path 55c, and the third paper discharge is performed. The entrance of the path 55c is opened and the entrance of the first reversing path 56a is blocked.

On the other hand, when an image is formed only on one side of the paper P in the double-sided mode, the paper P is conveyed to the first paper discharge path 55a and the second paper discharge path 55b on the downstream side of the fixing device 44 in the paper conveying direction. be done.
At this time, the switching claw 54 is rotated in the direction in which the paper P is guided to the first reversing path 56a, thereby opening the entrance of the first reversing path 56a and closing the entrance of the third discharge path 55c. do. The sheet P guided to the first reversing path 56a by the switching claw 54 passes between a sheet discharging roller 53a rotating in the sheet discharging direction discharged from the main body housing 90 and a reversing roller 53c facing the discharging roller 53a. passed between. The paper ejection roller 53a rotates the paper P in the sheet ejection direction at least until the trailing edge of the paper P passes through the switching claw 54, and temporarily moves the leading end of the paper P from the main body housing 90 to the stack section 91 side. paper is ejected properly. Then, before the trailing edge of the paper P leaves between the paper discharge roller 53a and the reversing roller 53c, the paper P is switched by rotating the paper discharge roller 53a in the sheet reversing direction opposite to the sheet discharging direction. back up.

After the trailing edge of the paper P passes through the switching claw 54 and before the discharge roller 53a rotates in the reverse direction, the switching claw 54 is rotated in the direction in which the paper P is guided to the second reversing path 56b. The path exit of the second reversing path 56b is opened, and the path exit of the second paper discharge path 55b is closed.
The sheet P that has been switched back is transported to the first reversing path 56 a , the second reversing path 56 b , and the third reversing path 56 c , and then transported to the reversing and re-feeding path 60 . Thus, in the double-sided mode, the reversing path 56 used for reversing is used, which consists of the first reversing path 56a, the second reversing path 56b, and the third reversing path 56c.

FIGS. 3A and 3B are diagrams for explaining the configuration of the discharge reversing path 50 for the sheet P conveyed from the fixing device 44, FIG. is an explanatory diagram in which the rear door 51 is opened. For the sake of explanation, the rear door 51 is provided on the rear surface, but it may be provided on the side surface or the front surface depending on the device configuration.
As shown in FIG. 3B, the rear door 51, which is an opening/closing member, has an opening/closing cover 59 and a rear guide member 58, and is rotatably attached to a support shaft 51a provided at the bottom of the main body housing 90. It holds a swinging guide portion 57 as a swinging member.

As shown in FIG. 3A, the paper discharge roller 53a is a roller that is used for both paper discharge and reversal. Focusing on the paper discharge path 55, the paper discharge roller 53a is arranged downstream in the paper transport direction of the third paper discharge path 55c, which is a part of the paper discharge path 55, and is used when the paper P is discharged. The paper discharge roller 53b contacts the paper discharge roller 53a to form a paper discharge nip portion 53d.
On the other hand, focusing on the reversing path 56, the discharge roller 53a is arranged on the first reversing path 56a, which is a part of the reversing path 56, on the stack section 91 side. A reversing roller 53c, which is a driven roller used when reversing the paper P, abuts against the discharge roller 53a to form a reversing nip portion 53e. The paper discharge roller 53a, the paper discharge roller 53b, and the reversing roller 53c constitute the paper discharge reversing roller section 53. As shown in FIG.

Further, as shown in FIG. 3A, a paper discharge path 55 from a fixing roller 44a as a conveying roller that fixes toner onto the paper P while conveying the paper P of the fixing device 44 to a paper discharge roller 53a, and a paper discharge path 55. Between the roller 53a and the reversing/re-feeding path 60, between the reversing path 56, a relay conveying roller 52a is provided immediately after the fixing roller 44a. Incidentally, the fixing roller 44a, the relay conveying roller 52a, and the paper discharging roller 53a described above are conveying rollers for conveying the paper P by a pair of rollers.

A paper ejection relay roller 52b as a third transportation roller used when transporting the paper P in the transportation direction A from the fixing roller 44a to the paper ejection roller 53a is in contact with the relay transportation roller 52a. A nip portion 52d is formed. The paper P immediately after passing through the fixing device 44 is passed through the paper ejection relay nip portion 52d, and the paper P is conveyed in the conveying direction A in FIG. is stabilizing. By stabilizing the transportation of the paper P, the fixability of the fixing device 44 can be stabilized, and a good fixed image can be obtained.

In addition, the relay conveying roller 52a is in contact with the reversing relay roller 52c as a first conveying roller used when conveying the paper P in the conveying direction B from the discharge roller 53a to the reversing and re-feeding path 60 (see FIG. 1). They are in contact with each other to form a reversing relay nip portion 52e.
The relay conveying roller section 52 is configured by the relay conveying roller 52a, the discharge relay roller 52b, and the reversing relay roller 52c.

As shown in FIG. 3(b), the relay conveying roller 52a is held by a swinging guide portion 57 which is swingably attached to the rear door 51, which is an opening/closing member. It is held by the portion 57 .

In order to stably convey the paper P immediately after passing through the fixing device 44 over time, it is necessary to keep the nip pressure of the discharge relay nip portion 52d constant over time. Therefore, in the present embodiment, the discharge relay roller 52b and the relay transport roller 52a are held by the swing guide portion 57, and the nip pressure of the discharge relay nip portion 52d is maintained even when the rear door 51 is opened. It is configured so that As a result, the nip pressure of the discharge relay nip portion 52d can be maintained constant over time. Therefore, the paper P immediately after passing through the fixing device 44 can be stably transported over time by the paper discharge relay roller 52b and the relay transport roller 52a.

On the other hand, in the reversing path 56, unlike the discharge path 55, even if the transportability of the paper P is somewhat disturbed, the image forming process such as the fixing process is not affected. Therefore, unlike the discharge relay nip 52d, the reversal relay nip 52e does not need to keep the nip pressure constant over time. Therefore, the reversing relay roller 52c is held by the rear guide member 58 instead of the rocking guide portion 57 that holds the relay conveying roller 52a. Then, when the rear door 51 is opened, the swing guide portion 57 swings to reduce the nip pressure of the reversing relay nip portion 52e, thereby removing the paper P jammed in the paper discharge path 55. make it easy.

In this embodiment, the change in the nip pressure of the reversing relay nip portion 52e interlocked with the opening and closing of the rear door 51 is realized by the following configuration. That is, when the rear door 51 is closed, the swing guide portion 57 is positioned on the fixing device 44 (see FIG. 11). At the time of this positioning, the swing guide portion 57 is pushed toward the rear guide member 58 by the positioning portion of the fixing device 44, so that the nip pressure of the reversing relay nip portion 52e is increased to a nip pressure that enables the paper P to be transported. be done. Then, when the rear door 51 is opened and the positioning of the swing guide portion 57 is released, the swing guide portion 57 swings with respect to the rear guide member 58, and the nip pressure of the reverse relay nip portion 52e is reduced. . That is, in this embodiment, the positioning portion for positioning the swing guide portion 57 of the fixing device 44 functions as a nip pressure changing means of the reversing relay nip portion 52e. The means for changing the nip pressure of the reversing relay nip portion 52e is not limited to the positioning portion of the fixing device 44. When the rear door 51 is closed, at least the relay conveying roller 52a holding side of the swing guide portion 57 is moved to the rear guide portion. The body housing 90 may be used as long as it is configured to be pushed into the member 58 by a specified amount.
The fixing device 44 is a detachable unit that can be attached to and detached from the body housing 90 and is positioned in the body housing 90 .

Next, a state in which the rear door 51 is opened will be described with reference to FIG. 3(b).
As shown in FIG. 3B, when the rear door 51 is rotated and opened for jam processing, the intermediate conveying roller section 52 rotates together with the swing guide section 57 and the rear guide member 58 . For this reason, on the side of the main body housing 90, the area surrounded by an ellipse in FIG. The first reversing path 56a of is wide open. In addition, the route entrance of the reversing retransmission route 60 is also opened.
As a result, the jammed paper can be easily found in the fixing device 44, the discharge path 55, the first reversing path 56a of the reversing path 56, and the reversing refeed path 60, and the jam can be easily removed.

Further, by opening the rear door 51, the second reversing path 56b and the third reversing path 56c of the reversing path 56 are opened on the rear door 51 side. Also, the pressure between the rear guide member 58 and the swing guide portion 57 (the force pushing the swing guide portion 57 into the rear guide member 58) is released. As a result, the nip pressure of the reversing relay nip portion 52e is also weakened, and the jammed paper jammed in the reversing path 56 (the second discharge path 55b and the third discharge path 55c) can be easily cleared.
Therefore, in addition to taking out jammed paper in the paper discharge path 55, it is possible to provide the paper discharge reversal path 50 that allows easy removal of jammed paper in the reversal path 56. - 特許庁

In addition to the printer 100 shown in FIG. 1, the image forming apparatus to which the sheet discharge reversing path 50 of the present embodiment can be applied includes a printer, a multifunction machine, and a multifunction machine in which the fixing device cannot be easily removed. This is particularly effective in printers, multifunction machines, and the like, which have a narrow jam take-out space, such as those for small sheets of A4 size or smaller in width.

In short, the relay conveying roller 52a and the discharge relay roller 52b, which are the fixing exit roller pair, between the fixing roller 44a and the discharge roller 53a are held by the swing guide portion 57, and the swing guide portion 57 is an opening/closing member. It is provided in the rear door 51 so that it can swing. As a result, the jammed paper can be easily found by opening the rear door 51 when the jam of the paper P occurs on the downstream side of the fixing device 44 in the paper conveying direction, and the jam can be cleared without removing the fixing device 44.例文帳に追加

Further, the relay conveying roller 52a and the discharge relay roller 52b, which are the fixing outlet roller pair, are held by the swinging guide portion 57 (see FIG. 3) of the rear door 51, and the reversing relay roller 52c is held by the rear guide member 58 of the rear door 51. is held in As a result, when the rear door 51 is opened, pressure is released from the relay conveying roller 52a and the reversing relay roller 52c, which are the double-sided entrance roller pair. Therefore, in the reversing path 56, the paper P can be removed from the relay conveying roller 52a without applying a strong pressure to the jammed paper.

Further, the position of the paper P in each conveyance path of the paper discharge reversing path 50 during jam processing will be described in detail with reference to the drawings.
FIGS. 4A and 4B are explanatory diagrams of the position of the paper P when jamming a jam that occurred during paper ejection, FIG. is an explanatory diagram in which the rear door 51 is opened.

As shown in FIG. 4A, in a state in which a jam occurs at the time of paper ejection, the paper P in the paper ejection path 55 is separated from the fixing roller 44a and the pressure roller 44b, the relay transport roller 52a and the paper ejection relay roller 52b, The paper P is held (nipped) between the paper discharge roller 53a and the paper discharge roller 53b. A sheet P having a short length in the sheet conveying direction may be held (nipped) by at least two of the three roller pairs.
In the printer 100 (discharge reversing path 50) of the present embodiment, as shown in FIG. 4B, when the rear door 51 is opened during jam processing, the discharge path 55 is opened.

In this embodiment, the swing guide portion 57 holds the discharge relay roller 52b and the relay conveyance roller 52a in order to stably convey the sheet immediately after passing through the fixing device 44 over time. Therefore, even if the rear door 51 is opened, the nip pressure of the discharge relay nip portion 52d is maintained at a nip pressure that allows the paper to be conveyed. Therefore, in the present embodiment, the rear door 51 is opened while the paper P in the paper discharge path 55 is held (nipped) between the relay transport roller 52a and the paper discharge relay roller 52b. Since the relay conveying roller 52a and the discharge relay roller 52b are provided on the rear door 51 side, when the rear door 51 is rotated and opened, the discharge relay nip portion 52d and the fixing roller 44a are engaged. The distance from the fixing nip portion 44c formed with the pressure roller 44b increases. At this time, if the nip pressure of the fixing nip portion 44c is high, the area of the paper P in the paper discharge path 55 from the fixing nip portion 44c to the paper discharge relay nip portion 52d is pulled, and may eventually break. There is

Therefore, in the present embodiment, when a jam occurs, the distance between the shaft centers of the pressure roller 44b and the fixing roller 44a is widened to increase the nip pressure of the fixing nip portion 44c to the nip pressure of the discharge relay nip portion 52d. make weaker than Specifically, the nip pressure of the fixing nip portion 44c is set lower than the nip pressure of the discharge relay nip portion 52d and lower than the rigidity (strength) of the paper P. As a result, when the rear door 51 is rotated and opened, the nip pressure of the paper discharge relay nip portion 52d pulls the paper P in the paper discharge path 55 upstream in the paper transport direction from the paper discharge relay nip portion 52d. As a result, the portion of the sheet P held (nipped) by the fixing roller 44a and the pressure roller 44b in the sheet ejection path 55 moves in the sheet conveying direction. Then, finally, the trailing edge of the paper P comes out of the fixing nip portion 44c. As a result, the area of the paper P in the paper discharge path 55 from the fixing nip portion 44c to the paper discharge relay nip portion 52d is not broken. The nip pressure of the output relay nip portion 52d may be set higher than the nip pressure of the fixing nip portion 44c without reducing the nip pressure of the fixing nip portion 44c.

Further, as the rear door 51 is rotated and opened, the distance between the discharge relay nip portion 52d and the discharge nip portion 53d formed by the discharge roller 53a and the discharge roller 53b increases. , the paper P in the paper discharge path 55 is pulled between the paper discharge relay nip portion 52d and the paper discharge nip portion 53d. Therefore, if both the nip pressure at the discharge relay nip portion 52d and the nip pressure at the discharge nip portion 53d are strong, the paper P breaks in the area from the discharge relay nip portion 52d to the discharge nip portion 53d. There is a risk. Therefore, in the present embodiment, the nip pressure of the discharge relay nip portion 52d is set lower than the nip pressure of the discharge nip portion 53d and lower than the rigidity (strength) of the paper P. As a result, when the rear door 51 is rotated and opened, the nip pressure of the paper discharge nip portion 53d pulls the paper P in the paper discharge path 55 downstream in the paper transport direction from the paper discharge relay nip portion 52d. Then, the portion of the paper P in the paper discharge path 55 held (nipped) by the relay transport roller 52a and the paper discharge relay roller 52b moves in the paper transport direction. Then, finally, the trailing edge of the paper P exits the paper discharge relay nip portion 52d. As a result, the paper P in the paper discharge path 55 is not broken in the area from the paper discharge relay nip portion 52d to the paper discharge nip portion 53d.

In this embodiment, the nip pressure of the fixing nip portion 44c<the nip pressure of the discharge relay nip portion 52d<the nip pressure of the discharge nip portion 53d. Therefore, when the rear door 51 is completely opened, as shown in FIG. 4B, the leading end of the paper P in the paper discharge path 55 is held by the paper discharge roller 53a and the paper discharge roller 53b. exposed. Therefore, the paper P in the paper discharge path 55 can be easily removed.

When the rear door 51 is opened, the paper P in the paper discharge path 55 is pulled out of the paper discharge relay nip portion 52d. The rear door 51 is rotated and opened while the sheet P is held (nipped) between the relay conveying roller 52a and the discharge relay roller 52b. As described above, the relay conveying roller 52a and the discharge relay roller 52b are provided on the rear door 51 side. changes every moment, and the curved state of the paper P in the discharge path 55 changes every moment. In this embodiment, the relay conveying roller 52a and the discharge relay roller 52b are provided in a swinging guide portion 57 which is swingably provided with respect to the rear door 51. As shown in FIG. Therefore, the swing guide portion 57 swings according to the curving state of the paper P in the discharge path 55, and the direction in which the paper P exits the discharge relay nip portion 52d can be changed according to the curving state. can. As a result, even if the rear door 51 is rotated and opened while the paper P in the paper discharge path 55 is held (nipped) between the relay transport roller 52a and the paper discharge relay roller 52b, the paper cannot be discharged. The curved state of the paper P in the path 55 can be smoothly changed, and the application of a load to the paper P or the like can be suppressed.

FIGS. 5A and 5B are explanatory diagrams of the position of the paper P when jamming a jam that occurred during reversal. FIG. , and a rear door 51 opened.
As shown in FIG. 5A, during reversal, a reversal nip portion 53e between the discharge roller 53a and the reversal roller 53c of the discharge reversal roller portion 53, and a reversal relay nip portion 52e between the relay conveying roller 52a and the reversal relay roller 52c. The sheet P in the reversing path 56 is held between the .
In the printer 100 (discharge reversing path 50) of this embodiment, as shown in FIG. is no longer pressurized. As a result, the nip pressure of the reversing relay nip portion 52e is reduced, and the sheet holding force is reduced or eliminated. As a result, when the rear door 51 is rotated and opened, the sheet P in the reversing path 56 is pulled out from the third reversing path 56 c and the second reversing path 56 b of the reversing path 56 . Then, as shown in FIG. 5B, when the rear door 51 is completely opened, the leading end side is exposed while being held by the discharge roller 53a and the reversing roller 53c. Therefore, the paper P in the reversing path 56 can also be easily removed.

FIG. 6 is an exploded perspective cross-sectional view showing the fixing device 44, the swing guide portion 57, and the rear door 51. As shown in FIG. FIG. 6(a) is a view seen obliquely from the front, and FIG. 6(b) is a view seen obliquely from the rear. In the following description, the front-rear direction of the device is the Y direction, the axial direction is the X direction, and the vertical direction is the Z direction.

The rear door 51 as an opening/closing member includes an opening/closing cover 59 and a rear guide member 58 fastened to the opening/closing cover 59 . The rear guide member 58 rotatably holds a reversing relay roller 52c, which is a first transport roller, and guides the sheet conveyed to the third reversing path 56c below the reversing relay roller 52c. It has a rear guide portion 58c. Further, the rear guide member 58 has a second post-reversal guide portion 58d that guides the sheet conveyed to the second reversal path 56b above the reversal relay roller 52c. The first post-reversal guide portion 58c and the second post-reversal guide portion 58d are formed continuously except for the opening for bringing the reversal relay roller 52c into contact with the relay conveying roller 52a.

The swinging guide portion 57 as a swinging member has a pre-swinging guide member 57a, a swinging discharge guide member 57b, a first swinging guide member 57c, and a second swinging guide member 57d. are doing. The swinging discharge guide member 57b, the first swinging guide member 57c, and the second swinging guide member 57d are attached to the pre-swing guide member 57a.

The pre-swing guide member 57a is opposed to the first post-reversal guide portion 58c of the rear guide member 58, and includes a first pre-reversal guide portion 57a1 that guides the sheet conveyed to the third reversal path 56c; It has a first discharge lower guide portion 57a2 (see FIG. 6B) that guides the sheet conveyed to the discharge path.

The swinging paper discharge guide member 57b holds a plurality of paper discharge relay rollers 52b as third conveying rollers arranged side by side in the X direction (axial direction). It has a first paper discharge upper guide portion 57b1 that guides the paper conveyed to the first paper discharge path so as to face the lower guide portion 51a2 (see FIG. 6B). Further, the swinging paper ejection guide member 57b has a second pre-paper ejection guide portion 57b2 that guides the paper conveyed to the second paper ejection path 55b (see FIG. 6B). Further, the swinging paper ejection guide member 57b has a swinging guide positioning protrusion 61 positioned in the device body side positioning groove 44d of the fixing device 44. As shown in FIG.

The first swinging guide member 57c rotatably supports the intermediate conveying roller as the second conveying roller. In addition, on the front side (+Y direction) of the first rocking guide member 57c, there is provided a paper ejection guide portion 57c1 (see FIG. 6A) for guiding the paper that has passed through the paper ejection relay nip portion 52d. A reversal entrance guide portion 57c2 is provided on the rear side (-Y direction) to guide the entry of the sheet into the reversal relay nip portion (see FIG. 6B).

The second swinging guide member 57d faces the second pre-discharge guide portion 57b2 of the swinging paper discharge guide member 57b to the front side (+Y direction) to guide the paper conveyed to the second paper discharge path 55b. A second post-discharge guide portion 57d1 (see FIG. 6A) is provided. On the rear side (−Y direction), a second pre-reversal guide portion 57d2 (see FIG. 6(b)) is provided.

The upstream end (lower end) of the second swinging guide member 57d in the paper ejection direction is axially different from the downstream end (upper end) of the first swinging guide member 57c in the paper ejection direction. (See FIG. 6(a)).

Next, positioning and holding of each member constituting the swing guide portion 57 will be described. In the following description, one axial end side will be described, but the other end side has the same configuration.
FIG. 7 is an exploded perspective view of the main parts of the vicinity of the swing guide portion 57 as viewed from above.
As shown in FIG. 7, the side wall portion 157 of the pre-swing guide member 57a has a main discharge guide reference positioning hole 157d for positioning and holding the swinging discharge guide member 57b and a secondary discharge guide reference positioning hole 157c. are provided at predetermined intervals in the vertical direction (Z direction). Two paper discharge guide positioning projections 57b3 and 57b4 are provided on the side surface of the rocking paper discharge guide member 57b with a predetermined space therebetween in the vertical direction. The inner diameter of the ejection guide main reference positioning hole 157d is approximately the same as the outer diameter of the ejection guide positioning protrusion 57b3, and the ejection guide secondary reference positioning hole 157c is an elongated hole extending in the vertical direction (Z direction). be.

The first ejection guide positioning protrusion 57b3 of the swinging ejection guide member 57b fits into the ejection guide main reference positioning hole 157d, and the second ejection guide positioning protrusion 57b4 fits into the ejection guide secondary reference positioning hole 157c. By fitting, the swinging discharge guide member 57b is positioned and held by the front swinging guide member 57a.

Further, in the side wall portion 157 of the pre-swing guide member 57a, a middle guide main reference positioning hole 157a for positioning and holding the second swinging guide member 57d and a middle guide sub-reference positioning hole 157b are formed in the vertical direction (Z direction). ) in a direction inclined approximately 45° to the front side (+Y direction).

The second swinging guide member 57d is provided with a positioning shaft 57d3 whose end fits into the middle guide main reference positioning hole 157a, and a middle guide positioning protrusion 57d4 that fits into the middle guide secondary reference positioning hole 157b. ing.

The inner diameter of the middle guide main reference positioning hole 157a is approximately the same as the outer diameter of the positioning shaft 57d3. It has an elongated hole shape extending forward (in a direction inclined approximately 45° toward the +Y direction).

As indicated by an arrow W1 in the figure, the tip of the positioning shaft 57d3 is fitted into the middle guide main reference positioning hole 157a, and as shown by an arrow W2 in the figure, the middle guide positioning protrusion 57d4 is fitted into the middle guide secondary reference positioning hole 157b. By inserting, the second during-swing guide member 57d is positioned and held by the pre-swing guide member 57a.

The side wall portion 157 of the pre-swing guide member 57a has a holding hole 157e into which the holding protrusion 57c3 of the first swinging guide member 57c is fitted, and a relay hole held by the first swinging guide member 57c. A bearing mounting hole portion 157f is provided in which a bearing for receiving the shaft 152a of the conveying roller is mounted.

The first during-swing guide member 57c functions as a pre-swing guide member by fitting the holding projection 57c3 into the holding hole 157e and passing the shaft 152a of the intermediate conveying roller through the bearing mounted in the bearing mounting hole 157f. It is positioned and held by 57a.

Thus, in the present embodiment, the swinging paper discharge guide member 57b, the first swinging guide member 57c, and the second swinging guide member 57d, which constitute the swinging guide portion 57, are integrated into one member. It is positioned and held by (pre-swing guide member 57a). As a result, the accumulation of manufacturing errors and assembly errors can be minimized, and the pre-swinging guide member 57a, the swinging discharge guide member 57b, the first swinging guide member 57c, and the second swinging guide member 57c can be combined. It is possible to improve the accuracy of the positional relationship of the member 57d. Therefore, the nip pressure of the discharge relay nip portion 52d can be set to the target nip pressure, and the paper P immediately after passing through the fixing device 44 can be stably conveyed by the discharge relay roller 52b and the relay conveying roller 52a. can do.

Next, the holding of the rocking guide portion 57 to the rear door 51, which is a feature of this embodiment, will be described. In the following description, one axial end side will be described, but the other end side has the same configuration.
8A and 8B are diagrams illustrating a structure for holding the swing guide portion 57 to the rear door 51. FIG.
At the lower part of the side surface of the rear guide member 58, a swing guide holding protrusion 58a having a cross-shaped cross section is provided. Further, an elliptical or long hole-shaped swing guide holding hole 58b whose major axis is in the front-rear direction (Y direction) is provided in the upper part of the rear guide member 58 which is different from the swing guide holding projection 58a in the vertical direction. there is

In the lower portion of the side wall portion 157 of the pre-pivoting guide member 57a, a guide held hole 64 elongated in the vertical direction and held by the pivoting guide holding projection 58a is provided. A swing guide held projection 65 that is held in the swing guide holding hole 58b is provided on the upper portion of the side wall portion 157 of the front swing guide member 57a.

The vertical (Z-direction) length β1 of the guide held hole 64 is longer than the vertical (Z-direction) length β2 of the swing guide holding projection 58a. On the other hand, the longitudinal (Y-direction) length α1 of the guide held hole 64 is substantially the same (slightly longer) than the longitudinal (Y-direction) length α2 of the swing guide holding projection 58a.

Both the long axis B2 and the short axis A2 of the elliptical swing guide holding hole 58b are longer than the diameter d of the swing guide held projection 65. As shown in FIG.

9 is a diagram showing a state in which the swing guide portion 57 is held by the rear door 51, and FIG. 10 is an enlarged view of the dashed line H in FIG.
As shown in the figure, the swing guide holding protrusion 58a provided on the rear guide member 58 is inserted into the guide held hole 64 provided on the front swing guide member 57a. The swing guide portion 57 is held by the rear door 51 by passing through the swing guide holding hole 58 b provided in the rear guide member 58 .

As shown in FIG. 10, the cross-shaped rocking guide holding protrusion 58a has a tapered shape that tapers toward the top. As a result, the swing guide holding projection 58a can be easily fitted into the guide held hole 64. As shown in FIG. Further, the end portion 58a1 of the portion extending in the front-rear direction of the cross-shaped swing guide holding projection 58a has an arc shape. With such a configuration, the guide held hole 64 is relatively rotatable within a predetermined range in the X direction (axial direction) with respect to the swing guide holding projection 58a.

As described above, the front-rear direction (Y-direction) length α1 of the guide held hole 64 is substantially the same (slightly longer) than the front-rear direction (Y-direction) length α2 of the swing guide holding projection 58a. The lower portion of the swing guide portion 57 held on the rear door 51 by the cross-shaped swing guide holding protrusions 58a is positioned and held in the front-rear direction (Y direction).

On the other hand, since the vertical (Z-direction) length β1 of the guide held hole 64 is longer than the vertical (Z-direction) length β2 of the swing guide holding projection 58a, the lower portion of the swing guide portion is held by the rear door 51 (rear guide member 58) so as to be movable within a predetermined range in the vertical direction (Z direction). Furthermore, as shown in FIG. 10, the end portion 58a1 of the portion extending in the front-rear direction of the cross-shaped swing guide holding projection 58a is arc-shaped, so that the lower portion of the swing guide portion is axially ( X direction) is held by the rear door 51 so as to be rotatable within a predetermined range.

Further, the swing guide holding hole 58b through which the swing guide held projection 65 penetrates has an elliptical shape in which both the long axis B2 and the short axis A2 are longer than the diameter d of the swing guide held projection 65. , the upper portion of the swing guide portion 57 is held by the rear door 51 so as to be movable in the YZ plane.

Since the swing guide portion 57 is held by the rear door 51 in this manner, the swing guide portion 57 can be moved vertically (Z direction) and axially (X axis) with the swing guide holding projection 58a as a fulcrum. (rotation) is held by the rear door 51 so as to be swingable. Therefore, when the rear door 51 is opened, the swing guide portion 57 swings in the vertical direction (Z direction) with respect to the rear door 51 and in the axial direction (around the X axis) about the swing guide holding protrusion 58a. As a result, the nip pressure of the reversing relay nip portion 52e can be reduced or eliminated. Thereby, the paper P in the reversing path 56 can be easily removed.

Further, since the rocking guide portion 57 can rock around the rocking guide holding projection 58a as a fulcrum, the paper P in the paper discharge path 55 is held (clamped) between the relay transport roller 52a and the paper discharge relay roller 52b. ), the rocking guide portion 57 can rock according to the curved state of the paper P in the paper discharge path 55 when the rear door 51 is rotated and opened. As a result, even if the rear door 51 is rotated and opened while the paper P in the paper discharge path 55 is held (nipped) between the relay transport roller 52a and the paper discharge relay roller 52b, the paper cannot be discharged. The curved state of the paper P in the path 55 can be smoothly changed, and the application of a load to the paper P or the like can be suppressed.

FIG. 11 is a cross-sectional perspective view of a main part showing how the swing guide positioning projection 61 of the swing guide portion 57 is fitted into the device main body side positioning groove 44d of the fixing device.
As shown in the figure, the fixing bracket 144 of the fixing device 44 is provided with a recessed apparatus body side positioning groove 44d into which the swing guide positioning protrusion 61 is fitted. When the rear door 51 is closed with the support shaft 51a as a rotation axis, the swing guide positioning protrusion 61 moves forward (+Y direction) as indicated by the arrow V1 in the drawing, and the swing guide positioning protrusion 61 moves forward. It fits into the positioning groove 44d on the device main body side. As a result, the movement of the swing guide portion 57 in the vertical direction is restricted by the device main assembly side positioning groove 44d, and the swing guide portion 57 is positioned in the vertical direction (Z direction).

In this embodiment, the swing guide portion 57 is held so as to be vertically movable within a predetermined range with respect to the rear door 51 . Therefore, even if there are variations in the vertical position of the apparatus main assembly side positioning groove 44d and the opening/closing trajectory of the rear door 51 due to the accumulation of manufacturing errors and assembly errors, the swing guide positioning protrusion 61 will remain in the apparatus main body side positioning groove. The swing guide positioning protrusion 61 can be fitted into the apparatus main assembly side positioning groove 44d by moving the swing guide portion 57 in the vertical direction when fitting into the device main body side positioning groove 44d.

In this way, since the swing guide portion 57 is directly positioned on the fixing device, the positional relationship between the swing guide portion 57 and the fixing device is determined with high accuracy. The rocking guide portion 57 has a guide that forms a paper ejection path 55 that is a transport path for paper that has passed through the fixing device. Therefore, by accurately positioning the swing guide portion 57 in the fixing device, it is possible to stably convey the sheet that has passed through the fixing device.

Further, when the rear door 51 is closed, the swing guide held protrusion 65 hits the rear end of the swing guide holding hole 58b, and the movement of the upper side of the swing guide portion in the front-rear direction is restricted, and the axial direction (X direction). From this state, when the rear door 51 is further moved in the closing direction, the rocking guide portion 57 is pushed toward the rear guide member 58 by the apparatus body side positioning groove 44d, and the nip pressure of the reversing relay nip portion 52e is increased. , is increased to a prescribed nip pressure at which the paper P can be transported. Then, the rear door 51 is closed, and the rear door 51 is positioned in the main body of the apparatus.

Conventionally, the swing guide portion 57 is positioned on a member of the fixing device, and the rear door 51 is closed to position the apparatus main body. , the swing guide portion 57 is indirectly positioned with respect to the rear door 51 .

Thus, in the conventional configuration in which the swing guide portion 57 and the rear door 51 are positioned with respect to the apparatus main body, the swing guide portion 57 is indirectly positioned with respect to the rear door 51. It picks up manufacturing errors and assembly errors of multiple component parts that make up the As a result, the swing guide portion 57 cannot be accurately positioned with respect to the rear door 51 due to accumulation of manufacturing errors and assembly errors of the plurality of component parts constituting the apparatus main body. Due to the positional relationship with the door 51 (rear guide member 58), the nip pressure and the nip width of the reversing relay nip portion 52e forming a nip vary, and the sheet conveying force due to the relay conveying roller 52a and the reversing relay roller 52c. will fluctuate.

On the other hand, in the present embodiment, as described above, the lower portion of the swing guide portion 57 is directly moved forward and backward by the rear door 51 by the guide held hole 64 and the swing guide holding projection 58a as the positioning holding portion. (rear guide member 58). As described above, in this embodiment, the swing guide portion 57 has a portion that is directly positioned on the rear door 51 . It is possible to suppress variations in the positions of the swing guide portion 57 and the rear door 51 when the door is closed. As a result, variations in the nip pressure and nip width of the reversing relay nip portion 52e can be suppressed, and variations in the sheet conveying force between the relay conveying roller 52a and the reversing relay roller 52c can be suppressed.

Further, in this embodiment, the lower side of the swing guide portion 57 is positioned and held on the rear door 51 , but the upper side of the swing guide portion 57 may be positioned and held on the rear door 51 . In this case, a swing guide positioning protrusion 61 for positioning the fixing device is provided on the lower side of the swing guide portion.

The present embodiment has been described above with reference to the drawings, but the specific configuration is not limited to the configuration including the discharge reversing path 50 of the present embodiment described above, and is within the scope of the present invention. You may change the design of
For example, the same effect can be achieved with a configuration in which a discharge roller and a reversing roller are provided separately.
In addition, although the monochrome printer 100 having the discharge reversing path 50 of the present embodiment has been described as an example, it is not limited to such a configuration. The present invention can also be applied to an image forming apparatus such as an image forming apparatus, a document conveying apparatus that conveys a document to an image reading section, and the like.

What has been described above is only an example, and each of the following aspects has a unique effect.
(Aspect 1)
It has a first conveying roller such as a reversing relay roller 52c, an opening/closing member such as a rear door 51 that can be opened and closed with respect to the apparatus main body, and a second conveying roller such as a relay conveying roller 52a that contacts the first conveying roller. In a sheet conveying device such as the sheet discharge reversing path 50 including a swinging member such as a swinging guide portion 57 that is swingably held by an opening/closing member, the swinging member is held by a plurality of holding portions. One of the plurality of holding portions positions the rocking member in a specific direction perpendicular to the axial direction of the opening/closing member (in this embodiment, the front-rear direction of the device: Y direction). It is a positioning and holding portion such as a swing guide holding projection 58a that holds.
As in Japanese Patent Application Laid-Open No. 2002-100002, in a configuration in which the swinging member and the opening/closing member are indirectly positioned by positioning the swinging member and the opening/closing member with respect to the member of the apparatus main body, the member of the apparatus main body is Therefore, there is a possibility that the swinging member cannot be accurately positioned with respect to the opening/closing member. As a result, the contact pressure between the first conveying roller and the second conveying roller may vary, and the sheet conveying force may vary.

On the other hand, in aspect 1, the swinging member is positioned in a specific direction with respect to the opening/closing member and held by the opening/closing member by the positioning/holding portion. In this way, since the rocking member is directly positioned on the opening/closing member in a certain specific direction, the accuracy is higher than that in which the rocking member and the opening/closing member are indirectly positioned in a specific direction by another member. Often the swinging member can be positioned in a specific direction with respect to the opening/closing member. As a result, variations in the contact pressure between the first conveying roller and the second conveying roller can be suppressed, and variations in the sheet conveying force can be suppressed.

Further, since the swinging member is held by the opening/closing member so as to be movable in directions other than a specific direction, when the opening/closing member is opened, the swinging member swings relative to the opening/closing member about the positioning holding portion as a fulcrum. As a result, the contact pressure between the first conveying roller and the second conveying roller can be weakened as in the conventional art. As a result, jam processing can be easily performed in the same manner as in the conventional art.

(Aspect 2)
In aspect 1, the axial direction is the X direction, the specific direction (the front-rear direction of the device in this embodiment) is the Y direction, and the direction orthogonal to both the X direction and the Y direction (vertical direction in this embodiment) is Z. When an opening/closing member such as the rear door 51 is closed, the swinging member such as the swinging guide portion 57 is positioned at least in the Z direction by the main body positioning portion such as the apparatus main body side positioning groove 44d provided in the apparatus main body. is positioned at
According to this, as described in the embodiment, the swing member such as the swing guide portion 57 is positioned in the Y direction and the Z direction.
In addition, since the swinging member is positioned directly on the apparatus main body, the position of the swinging member such as the swinging guide portion 57 can be determined with high accuracy with respect to the apparatus main body. A sheet can be stably conveyed.

(Aspect 3)
In mode 2, the positioning and holding portion of the swinging member such as the swinging guide portion 57 (in this embodiment, constituted by the guide held hole 64 and the swinging guide holding protrusion 58a) is separated by a predetermined distance in the Z direction. The position is determined in the Z direction and the Y direction by a body positioning portion such as the device body side positioning groove 44d.
According to this, as described in the embodiment, the swing member such as the swing guide portion 57 can be positioned in the Y direction, the Z direction, and around the X axis.

(Aspect 4)
In mode 2 or 3, the swinging member such as the swinging guide portion 57 has a portion to be positioned such as the swinging guide positioning projection 61 that enters the positioning groove 44d on the device main body side, and the portion to be positioned is the main body positioning member. from the Y direction.
According to this, as described in the embodiment, even if the position of the main body positioning portion such as the device main body side positioning groove 44d and the opening/closing trajectory of the opening/closing member such as the rear door 51 vary due to manufacturing errors or assembly errors. , the rocking member moves in the Z direction to allow the positioned portion to enter the main body positioning portion.

(Aspect 5)
In any one of modes 1 to 4, when the axial direction is the X direction, the specific direction is the Y direction, and the direction perpendicular to both the X and Y directions is the Z direction, the swing member such as the swing guide portion 57 is: By the positioning holding portion and the second holding portion such as the swinging guide holding hole 58b which is provided at a predetermined distance in the Z direction from the positioning holding portion and holds the swinging member movably in the YZ plane. retained.
According to this, as described in the embodiment, the swing member such as the swing guide portion 57 can move in the Z direction within a predetermined range and can swing in the X direction within a predetermined range. It can be held by an opening/closing member such as the door 51 . As a result, when the opening/closing member is opened, the contact pressure between the first conveying roller such as the reversing relay roller 52c and the second conveying roller such as the relay conveying roller 52a can be reduced, and the jammed paper can be easily removed. becomes possible.

(Aspect 6)
In any one of modes 1 to 5, the swinging member such as the swinging guide part 57 has a third conveying roller such as the discharge relay roller 52b that contacts the second conveying roller such as the relay conveying roller 52a. The contact pressure between the second conveying roller and the third conveying roller is maintained when the opening/closing member such as 51 is opened.
According to this, as described in the embodiment, there is no backlash or the like, and the second conveying rollers such as the relay conveying roller 52a and the third conveying rollers such as the discharge relay roller 52b are stable over time. can be used to convey the sheet.

(Aspect 7)
In aspect 6, the second conveying rollers such as the relay conveying roller 52a are driving rollers that are rotationally driven, and the first conveying rollers such as the reversing relay roller 52c and the third conveying rollers such as the discharge relay roller 52b When the driven roller rotates following the conveying roller, the second conveying roller and the third conveying roller convey the sheet in the discharge direction to discharge the sheet to the outside of the apparatus main body, and the sheet is conveyed in the discharge direction The second conveying roller is rotated in the opposite direction, and the first conveying roller and the second conveying roller convey the sheet to a re-conveying path such as the reversing re-conveying path 60 of the apparatus main body in the direction opposite to the discharge direction.
According to this, the second conveying roller such as the relay conveying roller 52a can serve both as a roller for conveying the sheet in the discharge direction and as a conveying roller for conveying the sheet to a re-conveying path such as the reversing and re-conveying path 60. The number of parts can be reduced, and the cost and space of the device can be reduced.

(Aspect 8)
In any one of modes 1 to 7, the contact pressure between the first conveying roller such as the reversing relay roller 52c and the second conveying roller such as the relay conveying roller 52a when the opening/closing member such as the rear door 51 is opened is is weaker than the contact pressure between the first conveying roller and the second conveying roller when the cover is closed.
According to this, as described in the present embodiment, the sheet can be taken out without applying a strong pressure to the jammed sheet in the sheet reversing path.

(Aspect 9)
An image forming apparatus having a sheet conveying device includes the sheet conveying device according to any one of aspects 1 to 8 as the sheet conveying device.
According to this, a sheet such as paper can be stably conveyed, and a jammed sheet can be easily removed.

44: Fixing device 44a: Fixing roller 44b: Pressurizing roller 44c: Fixing nip portion 44d: Apparatus body side positioning groove 50: Paper discharge reversing path 51: Rear door 51a: Support shaft 51a2: First paper discharge lower guide portion 52: Relay conveying roller portion 52a: Relay conveying roller 52b: Discharge relay roller 52c: Reversing relay roller 52d: Discharge relay nip portion 52e: Reversing relay nip portion 53: Discharge reversing roller portion 53a: Discharge roller 53b: Discharge roller 53c: Reversing roller 53d: Paper ejection nip portion 53e: Reversing nip portion 54: Switching claw 55: Paper ejection path 55a: First paper ejection path 55b: Second paper ejection path 55c: Third paper ejection path 56: Reversing path 56a : First reversing path 56b : Second reversing path 56c : Third reversing path 57 : Swing guide portion 57a : Pre-swing guide member 57a1 : First pre-reverse guide portion 57a2 : First discharge lower guide portion 57b : Swing Moving paper discharge guide member 57b1: First upper paper discharge guide portion 57b2: Second paper discharge front guide portion 57b3: First paper discharge guide positioning projection 57b4: Second paper discharge guide positioning projection 57c: First swinging guide member 57c1 : Paper ejection guide portion 57c2 : Reversing entry guide portion 57c3 : Holding projection 57d : Second swinging guide member 57d1 : Second paper ejection guide portion 57d2 : Second pre-reversal guide portion 57d3 : Positioning shaft 57d4 : Middle guide Positioning protrusion 58 : Rear guide member 58a : Pivoting guide holding projection 58a1 : End 58b : Pivoting guide holding hole 58c : Guide part 58d after first reversal : Guide part 59 after second reversal : Opening/closing cover 60 : Reversing and resending Path 61 : Swing guide positioning protrusion 64 : Guide held hole 65 : Swing guide held protrusion 90 : Body housing 91 : Stack section 100 : Printer 144 : Fixing bracket 152a : Shaft 157 : Side wall section 157a : Middle guide main Reference positioning hole 157b: Middle guide secondary reference positioning hole 157c: Paper ejection guide secondary reference positioning hole 157d: Paper ejection guide main reference positioning hole 157e: Holding hole 157f: Bearing mounting hole portion P: Paper

JP 2017-202933 A

Claims (10)

an opening/closing member having a first conveying roller and capable of being opened/closed with respect to the apparatus main body;
A sheet conveying device having a second conveying roller that abuts on the first conveying roller and a swinging member that is swingably held by the opening and closing member,
The swinging member is held by the opening/closing member by a plurality of holding portions,
When the axial direction of the first conveying roller is the X direction, the front-rear direction of the device orthogonal to the X direction is the Y direction, and the direction orthogonal to both the X direction and the Y direction is the Z direction,
one of the plurality of holding portions is a positioning holding portion that positions and holds the swinging member in the Y direction with respect to the opening/closing member;
The positioning and holding portion is a holding projection that is inserted into the hole to be held,
The length of the held hole in the Z direction is longer than the length of the holding protrusion in the Z direction,
The sheet conveying device, wherein the rocking member is held by the opening/closing member so as to be movable within a predetermined range in the Z direction with respect to the opening/closing member. In the sheet conveying device according to claim 1,
the holding protrusion has a cross-shaped cross section having a portion extending in the Y direction and a portion extending in the Z direction;
The end surface of the portion extending in the Y direction of the holding projection has an arcuate surface, and the arcuate surface of the end portion of the portion extending in the Y direction contacts the inner surface of the held hole. A sheet conveying device. In the sheet conveying device according to claim 2,
A sheet conveying apparatus according to claim 1, wherein when the opening/closing member is closed, the rocking member is positioned at least in the Z direction by a main body positioning portion provided on the apparatus main body. In the sheet conveying device according to claim 3,
A sheet conveying apparatus according to claim 1, wherein a position of said swinging member which is a predetermined distance in said Z direction from said positioning holding portion is positioned in said Z direction and said Y direction by said main body positioning portion. In the sheet conveying device according to claim 3 or 4,
The rocking member has a positioned portion that enters the main body positioning portion,
A sheet conveying device, wherein the portion to be positioned enters the body positioning portion from the Y direction. The sheet conveying device according to any one of claims 1 to 5,
The rocking member includes the positioning holding part, and a second holding part which is provided at a predetermined distance from the positioning holding part in the Z direction and holds the rocking member movably within the YZ plane. A sheet conveying device, characterized in that it is held by: The sheet conveying device according to any one of claims 1 to 6,
The swinging member has a third conveying roller that contacts the second conveying roller,
A sheet conveying device, wherein a contact pressure between the second conveying roller and the third conveying roller is maintained when the opening/closing member is opened. In the sheet conveying device according to claim 7,
The second conveying roller is a driving roller that is driven to rotate,
The first conveying roller and the third conveying roller are driven rollers that rotate following the second conveying roller,
Conveying the sheet in a discharge direction for discharging the sheet to the outside of the apparatus main body by the second conveying roller and the third conveying roller;
rotating the second conveying roller in a direction opposite to when conveying the sheet in the discharging direction, and conveying the sheet in the direction opposite to the discharging direction by the first conveying roller and the second conveying roller; A sheet conveying device that conveys a sheet to a re-conveying path. The sheet conveying device according to any one of claims 1 to 8,
The contact pressure between the first and second transport rollers when the opening/closing member is opened is the contact pressure between the first and second transport rollers when the opening/closing member is closed. A sheet conveying device characterized by being weaker than. In an image forming apparatus equipped with a sheet conveying device,
An image forming apparatus comprising the sheet conveying device according to any one of claims 1 to 9 as the sheet conveying device.

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