JP2000109261A - Sheet path selector and image forming device having the selector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent damage to an actuator or flapper when an attachment on which the flapper is mounted is to be unintentionally dislodged from a housing while the actuator urges the flapper to select a changed sheet path. SOLUTION: A sheet path selector 81 comprises a flapper 505 that ordinarily opens one preselected of branch sheet paths defined within an attachment 500 separable from a housing 101, and a flapper actuation mechanism 91 placed in separable contact with the flapper 505 to change over it from the preselected sheet path to another. The housing 101 has either of the flapper 505 and flapper actuation mechanism 91; the other is placed in the attachment 500. An operator is disposed to return the flapper actuation mechanism 91 to its waiting position when the attachment 500 is to be dislodged from the housing 101 while the flapper actuation mechanism 91 moves out of its waiting position and urges the flapper 505 to select a changed sheet path.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet path switching device for switching a sheet path for guiding a sheet, and an image forming apparatus equipped with the device, such as a copier, a facsimile, a laser beam printer, or the like.

[0002]

2. Description of the Related Art Usually, a sheet discharging device is connected to a sheet discharging port of a printer, which is an example of an image forming apparatus, and aligns sheets discharged from the printer for each job and binds the sheets by binding means such as staples. Emissions were large, and large ones were common.

[0003] However, with the spread of desktop publishing, so-called DTP, such a sheet discharge device has come to be used in a small printer which is installed and used on a desktop.

Therefore, a discharge sheet stacking section is provided below the printer main body, and a flapper, which is a branching means for branching to the discharge sheet stacking section in a sheet discharge path of the printer main body, is provided on the printer main body side, and discharge is performed from the flapper. 2. Description of the Related Art There is a so-called lower-type sheet discharging device in which a sheet transporting unit that wraps downward to a sheet stacking unit is provided outside a printer main body.

As a result, it has become possible to provide an apparatus which can perform processing after sheet discharge such as bookbinding for a printer used on a desktop without substantially changing the installation area.

[0006]

At this time, care should be taken not to burden users who do not use the sheet discharging device with cost, and only the flapper is mounted on the printer body side.
An actuator for actuating the flapper,
It was provided on the sheet discharge device side.

[0007] Further, the sheet transport unit is configured to be attachable and detachable in consideration of jam clearance and maintenance at the transport branch path.

[0008] With the above configuration, it is possible to minimize the increase in the cost of the printer main body and improve the operability such as the jam processing.

However, with the above configuration, there is a problem that the actuator may be damaged if the sheet transport unit is accidentally removed from the printer body during use of the printer.

(Purpose) The present invention prevents the actuator or the flapper from being damaged when the flapper switches the sheet path by the actuator and the sheet transport unit as the detachable body is inadvertently removed from the printer body as the housing. Sheet path switching means capable of
It is another object of the present invention to provide an image forming apparatus having the sheet path switching unit.

[0011]

According to a first aspect of the present invention, there is provided a sheet path switching device including a flapper which always opens one predetermined sheet path among branch sheet paths formed in a detachable body detachable from a housing; A flapper operating mechanism that contacts the flapper in a separable manner and switches the flapper from the predetermined sheet path to another sheet path,
In the sheet path switching device provided with one of the flapper and the flapper operating mechanism in the housing and the other in the detachable body, the flapper operating mechanism operates from a standby position to move the flapper to the other sheet path. In the switched state, when the detachable body is taken out of the housing, an operating body that returns the flapper operating mechanism to the standby position is provided.

In the sheet path switching device according to the first aspect of the invention, when the flapper operating mechanism is operated to switch the flapper to another sheet path and the detachable body is carelessly taken out of the housing, the operating body is moved to the flapper operating mechanism. To the standby position, so that the detachable body is not taken out while the flapper operating mechanism and the flapper are in contact with each other,
Prevents damage to the flapper operating mechanism or flapper.

According to a second aspect of the present invention, the flapper always opens the predetermined sheet path by its own weight, and the flapper operating mechanism switches the flapper to the other sheet path against its own weight. It has become.

[0014] In the sheet path switching device according to a third aspect of the present invention, the detachable body can be attached to and detached from the housing substantially horizontally.

An image forming apparatus according to a fourth aspect of the present invention includes any one of the first to third aspects of the present invention and a sheet path switching device, and image forming means for forming an image on a sheet.

In the image forming apparatus according to a fifth aspect of the present invention, the detachable body is a reversing unit for reversing and conveying the sheet.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) A sheet path switching apparatus according to a first embodiment shown in FIGS. 3 and 4 is a laser beam printer (hereinafter simply referred to as a "printer") which is an image forming apparatus shown in FIGS. ).

A printer 100 incorporating a sheet path switching device 81 will be described with reference to FIGS.

The printer 100 is singly connected to a computer or connected to a network such as a LAN, prints the received information as an image on a sheet by a predetermined image forming process, and discharges the sheet. It is supposed to.

The first sheet supply device 200 includes a detachable sheet cassette 201 containing a plurality of sheets P.
And the sheets P stored in the sheet cassette 201 are separated one by one according to a predetermined sheet supply signal, and
And a separation sheet supply unit 202 that conveys the sheet to the first position. The first sheet supply device 200 also includes a sheet guide portion 203 that conveys the sheets P from the second and third sheet supply devices 300 and 400 that are disposed in a lower layer so that they can be used in a stacked manner. ing.

The second sheet feeding device 300 includes, similarly to the first sheet feeding device 200, a sheet cassette 301 for storing sheets P, a separation sheet feeding portion 302, and a sheet guide portion for conveying sheets P from below. 303.

The third sheet feeding device 400 has the same structure as the first and second sheet feeding devices 200 and 300. The sheet cassette 401 of the third sheet supply device 400 is formed so as to store more sheets P than the sheet supply cassettes 201 and 301 of the first and second sheet supply devices 200 and 300. Further, the length is long so that a long sheet can be used, and the rear end protrudes from the printer main body 101.

These sheet feeding devices 200, 300, 4
No. 00 is automatically positioned by a positioning pin and a fitting hole (not shown) having the same shape and electrically connected by lamination. The printer 100 is connected to the supply cassettes 201, 301, and 401.
Can detect the connection state.

Therefore, the user can select the number of stages and the capacity of the sheet supply cassette suitable for the specification environment from many variations.

The two-sided unit 500 includes a printer body 10
5, is configured to be mounted on the printer main body 101 from the left side in FIG.

The printer body 101 and the duplex unit 50
0 is also electrically connected by connectors provided on both sides, so that the power supply and communication from the printer main body 101 to the duplex unit 500 become possible, and the connection state can be confirmed on the printer main body 101 side. I have.
When performing a jam clearance or maintenance, the double-sided unit 500 is pulled out to the left in FIG. 5 and can be easily removed for work.

The sheet discharging device 600 includes the printer body 1
The sheets ejected from the sheet No. 01 are bundled face-down for each predetermined job via the extension guide section 800 and the vertical conveyance section 700, stapled at one place or a plurality of places, and discharged or stacked. Is a sheet discharging apparatus provided with bookbinding means for discharging and stacking the sheets face down.

The extension guide 800 includes first, second, and third
When the height of the printer 100 is increased by the sheet feeding devices 200, 300, and 400, the sheet is guided between the duplex unit 500 and the vertical transport unit 700.

The printer 100 shown in FIG. 1 has three types of first, second, and third sheet feeding devices 200, 300, and 40.
0 is attached, the extension guide 800 connects between the duplex unit 500 and the vertical transport unit 700.

A sheet P selectively supplied from a desired sheet supply device in accordance with a predetermined print signal is transferred in the printer 100 with an image formed by the image forming unit 119 with the print surface facing up. 120.

The sheet on which the image is fixed is moved by the FD flapper 121 according to a predetermined signal to the printer main body 101.
FD sheet discharge unit 125 provided at the upper part of the printer, or selectively branched and conveyed to double-sided unit 500.

The sheet P branched and transported to the duplex unit 500 activates the duplex transport sensor 501.

When the conveyed sheet is an instruction for double-sided printing, the double-sided conveyance sensor 501 actuated by the conveyed sheet P drives the downstream double-sided conveyance roller 502 at a predetermined timing to transfer the sheet. It is led to the reverse conveyance path 503. Next, after the sensor 501 detects that the rear end of the sheet P has passed through the two-sided conveyance sensor 501, the two-sided conveyance roller 50 is moved at a predetermined timing.
2 is driven in reverse. As a result, the sheet P is conveyed to the double-sided carry-in path 504, conveyed again to the printer 100, and printed on both sides.

Next, the operation of each unit when the conveyed sheet P is directed to the sheet discharge device 600 will be described.

Sheet P carried into double-sided unit 500
Actuates the two-sided conveyance sensor 501, the two-sided conveyance sensor 501
Signal to 21. The CPU 621 drives the downstream double-sided conveying roller 502 at a predetermined timing and outputs a signal to the sheet discharge device 600. The flapper solenoid 610 (see FIG. 3) provided in the vertical transport section 700
The plunger 611 is pulled, and the lever 612 rotatably attached to the plunger 611 is pulled downward about the rotation center shaft 613 as the rotation center (see FIG. 4).

Since the lever 612 is supported by the rotation center shaft 613, the lever 612 is rotated about the rotation center shaft 613, and the support side of the link lever 711 is rotated upward, so that the link levers 711, 811 To rotate the flapper 505 provided on the double-sided unit 500 by the rotation shaft 507 to open the conveyance path to the sheet discharge device 600 side. As a result, the sheet P is
0, the sheet discharging device 600 via the vertical conveying unit 700
It is in a state where it is carried into.

As shown in FIG. 1, the vertical transport section 700 is set up at a position where the sheet cassette 401 protruding from the printer main body 101 has escaped.
It is a little away from the exterior.

The sheet P is fed to a sheet discharge device 60 by a rotatable transport roller 702 urged by a transport roller 701.
0, an alignment sheet discharge roller 601 provided at
A rotatable alignment discharge sheet roller 602 urged by the alignment sheet discharge roller 601, and a sheet conveying path 712.
Is discharged to the sheet aligning section.

At this time, the sheet printed by the printer 100 with the printing surface up is wrapped around the printer main body 101 and discharged, so that the sheet is discharged face-down with the printing surface facing down, By a predetermined sheet processing process, staple processing is selectively performed for each job, and the bundle is discharged to the discharge tray 650.

Here, the attachment / detachment operation of the duplex unit 500 and the movement of the flapper 505 will be described with reference to FIGS.

The double-sided unit 500 can be pulled out substantially horizontally (in the direction of arrow A) with respect to the printer main body 101 when performing a jam clearance or maintenance. In the case of the jam processing, the job is stopped by a jam detection signal or the like, and the link lever 711 of the flapper 505 stops sucking the solenoid 610.
As shown in the figure, the image is returned to the frame side of the vertical transport unit 700.

At this time, the double-sided unit 500 is moved
It can be pulled out without any problem in the direction, and jam clearance and maintenance can be performed.

However, sometimes the user accidentally tries to pull out the duplex unit 500 during a normal job.

At this time, as shown in FIG. 4, the link lever 711 and the flapper link 811 are connected to the flapper 505.
The double-sided unit 500 is pulled out in the direction of arrow A while the actuated portion 506 integral with the unit 500 is pushed up.

A link lever guide 550 is provided on the lower surface of the exterior of the duplex unit 500 on the downstream side in the pulling-out direction of the actuated portion 506 of the flapper 505 of the duplex unit 500.

In the link lever guide 550, the link lever 711 and the flapper link 811
In the ON state where actuation is possible, the duplex unit 5
When 00 is pulled out, the flapper link 81 resists the urging force of the flapper link 811 and the link lever 711.
1 has a gentle inclined surface 550a.

Thus, even if the duplex unit 500 is inadvertently pulled out during the job, the flapper link 811
Is pushed downward by the inclined surface 550a of the guide portion 550, and pushes down the link lever 711 and the flapper link 811 against the urging force of the solenoid 610.
0 can be prevented from being damaged.

Also, when the double-sided unit 500 is pulled out and mounted, the inclined surface 550b of the link lever guide 550 smoothly pushes down the flapper link 811 so that it can be mounted without being damaged. .

Thus, the user can set the duplex unit 50
0 can be returned to the original mounting position to return to the normal use state.

In the above configuration, the flapper solenoid 610, the plunger 611, the lever 612, the rotation center shaft 613, the link lever 711, and the flapper link 81
1 and the like constitute a flapper operating mechanism 91.

The flapper operating mechanism 91, the flapper 505,
The actuated portion 506, the link lever guide portion 550, and the like constitute a sheet path switching device 81.

(Second Embodiment) FIG. 7 shows a sheet path switching device according to a second embodiment.

The solenoid 61 of the sheet path switching device
The lever 0, the lever 612, and the link lever 711 are disposed on the actuator base 751. Actuator base 751
Are a pair of guide holes 752, 752, which are long holes formed in the actuator base 751, and a pair of guides 750, which protrude from the vertical transport unit 700 and engage with the guide holes 752.
750 so as to be able to move up and down in the vertical transport unit 700.

An urging spring 753 is provided between the actuator table 751 and the vertical transport section 700, and the actuator table 751 is constantly urged upward.

Further, a projection 755 is provided on the actuator base 751.

The tip of the protruding piece 755 is connected to the extension guide 800
The lower end of a vertically movable rod 850 provided to be vertically movable is received. A rotatable roller 851 that contacts the link lever guide 550 is provided at the upper end of the vertical moving rod 850.

In such a configuration, the link lever 711 and the flapper link 811 are pushed up by the operation of the flapper solenoid 610, and the actuated portion 50
6. When the flapper 505 is rotated counterclockwise and tilted through 6 and the two-sided unit 500 is inadvertently pulled out in the direction of arrow A during actuation of the flapper 505, the inclined surface 550a of the link lever guide portion 550 can be obtained. Is roller 85
1. Push down the vertical moving rod 850. Then, the protruding piece 755
Is also pushed down, and the entire actuating table 750 is pushed down against the biasing spring 753. As a result, the link lever 711 and the flapper link 811 are lowered integrally with the actuator base 750, the upper end of the flapper link 811 is separated from the actuated portion 506, and the
Do not interfere with the 00 drawer.

In the above configuration, the actuator base 7
51, biasing spring 753, guide 750, guide hole 75
2. Projection piece 755, vertical moving rod 850, roller 851, flapper solenoid 610, plunger 611, lever 61
2. The rotation center shaft 613, the link lever 711, the flapper link 811 and the like constitute a flapper operating mechanism 92.

The flapper operating mechanism 92, the flapper 505,
The actuated portion 506, the link lever guide portion 550, and the like constitute a sheet path switching device 82.

(Third Embodiment) FIG. 8 shows a sheet path switching device according to a third embodiment.

The actuator base 751 has a rotating shaft 760
The vertical transfer unit 700 is rotatably provided, and is urged to rotate counterclockwise by an urging spring 754 to abut a stopper 757 on the vertical transfer unit 700 to be positioned.

The difference from the sheet path switching device of the second embodiment shown in FIG. 7 is that the projection 756 is shorter than the projection 755 and the link lever 711 is provided on the actuator base 751 so as to be able to move up and down. , And the other parts are almost the same. Therefore, the same reference numerals are given to the same parts, and the description of the parts will be omitted.

When the flapper 505 is rotated counterclockwise to guide the sheet toward the vertical guide portion 800 from the state shown in FIG. 8 (during actuation), the duplex unit 500 is pulled out carelessly. The roller 851 and the vertically moving rod 850 are lowered by the link lever guide 550, and the actuator base 751 is rotated in the direction of arrow C, so that the flapper link 811 is actuated by the actuated portion 50.
6 so that the drawer of the duplex unit 500 is not hindered.

The structure of the sheet path switching device is simpler than that of the sheet path switching device of the second embodiment because the actuator base 751 is provided so as to be vertically movable.

In the above configuration, the actuator table 7
51, rotating shaft 760, biasing spring 754, stopper 75
7, projecting piece 756, vertical moving rod 850, roller 851, flapper solenoid 610, plunger 611, lever 61
2, the rotation center shaft 613, the link lever 711, the flapper link 811 and the like constitute a flapper operating mechanism 93.

The flapper operating mechanism 92, the flapper 505,
The actuated portion 506, the link lever guide portion 550, and the like constitute a sheet path switching device 83.

(Fourth Embodiment) As shown in FIG. 9, a sheet path switching device according to a fourth embodiment and fifth and sixth embodiments described below is applied to a printer 102 having a lower height than the printer 100 shown in FIG. It has been incorporated. The printer 102 shown in FIG.
And second sheet feeding devices 2 in the printer 100 of FIG.
1 and 2, the third sheet feeding device 400 is provided in two stages.
The height is lower than 0 and no extension guide 800 is provided. Therefore, the duplex unit 500 and the vertical transport unit 700 are directly connected. 9 and 10, the same parts as those of the printer of FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted.

The sheet path switching device 84 of the fourth embodiment shown in FIGS. 11 to 13, the sheet path switching device 85 of the fifth embodiment shown in FIGS. 14 and 15, and the sixth embodiment shown in FIG. Since all of the sheet path switching devices 86 in the form are incorporated in the printer 102, FIG.
To 8 of the first embodiment shown in FIGS.
1. Sheet path switching device 8 of second embodiment shown in FIG.
2, and the configuration is the same as that of FIG. 8 except that the flapper link 811, the vertically movable rod 850, and the roller 851 are removed from the sheet path switching device 83 of the third embodiment.

Accordingly, in the sheet path switching devices 84, 85, 86 of the fourth to sixth embodiments, the same reference numerals are used for the same parts as those of the sheet path switching devices 81, 82, 83 of the first to third embodiments. The description of the operation is omitted.

That is, the fourth of FIGS. 11, 12 and 13
The sheet path switching device 84 of the embodiment includes a flapper operating mechanism 94, a flapper 505, an actuated portion 506,
It is composed of a link lever guide 550 and the like. The flapper operating mechanism 94 includes a flapper solenoid 610, a plunger 611, a lever 612, a rotation center shaft 613, a link lever 711, and the like.

The sheet path switching device 85 of the fifth embodiment shown in FIGS. 14 and 15 includes a flapper operating mechanism 95 and a flapper 5.
05, an actuated portion 506, and a link lever guide portion 550. The flapper operating mechanism 95 includes an actuator base 751, an urging spring 753,
Guide 750, guide hole 752, protruding piece 755, flapper solenoid 610, plunger 611, lever 612,
It comprises a rotation center shaft 613, a link lever 711, and the like.

The sheet path switching mechanism 86 according to the sixth embodiment shown in FIG. 16 includes a flapper operating mechanism 96, a flapper 505, an actuated portion 506, a link lever guide portion 550, and the like. Flapper operating mechanism 96
The flapper operating mechanism 93 includes an actuator base 751, a rotating shaft 760, a biasing spring 754, a stopper 757, a protrusion 756, a flapper solenoid 610, a plunger 611, a lever 612, a rotation center shaft 613, and a link lever 711. are doing.

In each of the above embodiments, the flapper 505 is connected to the printer main body (1).
01 or 102) and the flapper operating mechanism is provided on the vertical transport unit 700 side, but the arrangement relationship may be reversed.

[0075]

According to the sheet path switching device of the present invention, when the flapper operating mechanism is operated to switch the flapper to another sheet path, the detachable body may be inadvertently removed from the housing. Since the operating body forcibly returns the flapper operating mechanism to the standby position, the detachable body is prevented from being taken out while the flapper operating mechanism and the flapper are in contact with each other, thereby preventing damage to the flapper operating mechanism or the flapper, Thereafter, the sheet can be switched and conveyed reliably.

Since the image forming apparatus is provided with a sheet path switching device that is not easily damaged, the sheet is reliably fed, and an image can be formed accurately.

[Brief description of the drawings]

FIG. 1 is a schematic front sectional view of a printer in which a sheet path switching device according to first to third embodiments of the present invention is incorporated.

FIG. 2 is an exploded perspective view of a sheet discharge device, a vertical transport device, and an extension guide unit of the printer of FIG.

FIG. 3 is a front sectional view of the sheet path switching device according to the first embodiment.

FIG. 4 is a diagram illustrating the operation of the sheet path switching device according to the first embodiment.

FIG. 5 illustrates a sheet path switching device according to the first embodiment.
It is a front sectional view at the time of taking out a detachable body carelessly.

FIG. 6 is a partial perspective view of the sheet path switching device according to the first embodiment.

FIG. 7 is a front sectional view of a sheet path switching device according to a second embodiment.

FIG. 8 is a front sectional view of a sheet path switching device according to a third embodiment.

FIG. 9 is a front sectional view of a printer in which sheet path switching devices according to fourth to sixth embodiments of the present invention are incorporated.

FIG. 10 is an external perspective view of the printer of FIG. 9;

FIG. 11 is a front sectional view of a sheet path switching device according to a fourth embodiment.

FIG. 12 is an operation explanatory view of the sheet path switching device of the fourth embodiment.

FIG. 13 is a front sectional view of the sheet path switching device according to the fourth embodiment when a detachable body is taken out carelessly.

FIG. 14 is a front sectional view of a sheet path switching device according to a fifth embodiment.

FIG. 15 is a front sectional view of the sheet path switching device according to the fifth embodiment when a detachable body is carelessly taken out.

FIG. 16 is a front sectional view of a sheet path switching device according to a sixth embodiment.

[Explanation of symbols]

P sheet 81, 82, 83, 84, 85, 86 Sheet path switching device 91, 92, 93, 94, 95, 96 Flapper operating mechanism 100 Printer (image forming apparatus) 101 Printer main body (image forming apparatus main body) 102 Printer ( (Image Forming Apparatus) 119 Image Forming Unit 200 First Sheet Feeding Unit 201 Sheet Cassette 202 Separated Sheet Supply Unit 203 Sheet Guide Unit 300 Second Sheet Supply Device 301 Sheet Cassette 302 Separated Sheet Supply Unit 303 Sheet Guide Unit 400 Third Sheet feeding device 401 Sheet cassette 500 Double-sided unit 503 Reverse transport path (predetermined sheet path) 504 Double-sided loading path 505 Flapper 506 Actuated section 507 Rotation axis 550 Link lever guide section 550a Inclined surface 550b Inclined surface 551 Cutter section 600 Sheet discharging device 610 Flapper solenoid 611 Plunger 612 Lever 613 Rotating center axis 621 CPU of main body 650 Discharge tray 700 Vertical transport section 711 Link lever 712 Sheet transport path (other sheet paths) 800 Extension guide section 811 Flapper link 850 Up / down Moving rod 851 Roller

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Atsushi Ogata 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Tsuyoshi Waraya 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inside (72) Inventor Masayoshi Fukatsu 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Tomoyuki Araki 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. F-term (reference) 2H072 AA16 AA32 AB25 CA01 CB01 FA01 3F053 EA02 EA04 EA05 EC02 EC07 ED01 ED15

Claims (5)

[Claims] 1. A flapper that always opens one predetermined sheet path among branch sheet paths formed in a detachable body that is detachable from a housing, and the flapper is detachably contacted with the flapper to cause the flapper to contact the predetermined flapper. A flapper operating mechanism for switching from the sheet path to another sheet path, wherein the housing includes one of the flapper and the flapper operating mechanism, and the detachable body includes the other. In a state where the flapper operating mechanism is operated from the standby position and switches the flapper to the other sheet path,
A sheet path switching device, comprising: an operating body that returns the flapper operating mechanism to the standby position when the detachable body is taken out of the housing. 2. The flapper according to claim 1, wherein said predetermined sheet path is always opened by its own weight, and said flapper operating mechanism switches said flapper to said another sheet path against its own weight. 2. The sheet path switching device according to 1. 3. The sheet path switching device according to claim 1, wherein the detachable body is detachable substantially horizontally with respect to the housing. 4. An image forming apparatus according to claim 1, further comprising: a sheet path switching device according to claim 1, and image forming means for forming an image on a sheet. 5. The image forming apparatus according to claim 4, wherein the detachable body is a reversing unit for reversing and conveying the sheet.