Information
-
Patent Grant
-
6254086
-
Patent Number
6,254,086
-
Date Filed
Thursday, June 29, 200024 years ago
-
Date Issued
Tuesday, July 3, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Sughrue, Mion, Zinn, Macpeak & Seas, PLLC
-
CPC
-
US Classifications
Field of Search
-
International Classifications
-
Abstract
A sheet accommodating device comprises a first pinion (39a) rotatably disposed at a center of a table; second, third, fourth, and fifth pinions (39) which are rotatably disposed on the both sides of the table; a first regulating member (34) which has rack portions (36, 38) that can be engaged with the first pinion, second pinion and fourth pinion; a second regulating member (35) which has rack portions (37, 38) that can be engaged with the first pinion, third pinion and fifth pinion; and lock means (33) for positioning any one of the first and second regulating members.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a sheet accommodating device which is applied to a paper supplying section or a paper exhausting section of an image forming apparatus such as a laser printer, a copier, or the like.
2. Description of the Related Art
A sheet accommodating device applied to an image forming apparatus can be broadly classified into a small-sized type in which the sheet capacity is about 250 to 500 sheets, and a large-sized type in which the sheet capacity is about several thousands sheets.
Recently, a sheet accommodating device has been widely used, in which a regulating member for regulating a sheet position is provided so that the regulating member can be moved according to a size of a sheet to be used and so that it can correspond various sizes of sheets.
In case of the large-sized type of the sheet accommodating device, the corresponding depth is required. Therefore, the large-sized type of sheet accommodating device must be equipped with a regulating member having several times as large as a regulating member in the small-sized type of sheet accommodating device has. Since the regulating member of the large-sized type of the sheet accommodating device is generally formed as a sheet metal member or a thin plastic product, it cannot help being made of flexible material.
In case that the position of the regulating member having such the large size is changed according to the size of a sheet, conventionally, the regulating member is detached at every change, then reattached to the size position of the sheet to be used and fixed there. Therefore, the regulating member of the large size is troublesome in that it is inserted into slits provided at each size of the sheets to be fixed and that it is fixed by a fixing member such as a screw, a magnets or the like.
SUMMARY OF THE INVENTION
An object of the invention is to provide a sheet accommodating device which is superior in operationality and also can position the regulating member accurately.
In order to achieve the above object, a sheet accommodating device comprises a table on which sheets are stacked; a first pinion rotatably disposed at a center of the table; a second pinion rotatably disposed on one end side of the table; a third pinion rotatably disposed on the other end side of the table; a fourth pinion that is connected to the second pinion and arranged above the second pinion; a fifth pinion that is connected to the third pinion and arranged above the third pinion; a first regulating member which is arranged on one side of the table and has rack portions that can be engaged with the first pinion, second pinion and fourth pinion; a second regulating member which is arranged so as to be opposite to the first regulating member and has rack portions that can be engaged with the first pinion, third pinion and fifth pinion; and lock means for positioning any one of the first and second regulating members.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1
is a whole constitutional view of a laser printer in which a sheet accommodating device of the invention is mounted.
FIG. 2
is a schematic perspective view showing one embodiment of the sheet accommodating device of the invention.
FIG. 3
is a constitutional view showing a slide mechanism of a regulating member in the sheet accommodating device of the invention.
FIG. 4
is a constitutional view showing a lock mechanism of the regulating member in the sheet accommodating device of the invention.
FIG. 5
is a constitutional view showing another embodiment of the lock mechanism.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
An embodiment of a sheet accommodating device according to the invention will be described below in detail with reference to drawings.
FIG. 1
is a whole constitutional view of a laser printer in which a sheet accommodating device of the invention is applied to a paper supplying section. In
FIG. 1
, reference numerals
1
,
2
and
3
are sheet accommodating devices, of which the sheet accommodating device
3
has a larger sheet capacity than the other sheet accommodating devices
1
and
2
and can supply a large amount of sheets to the laser printer. The sheet accommodating devices
1
,
2
and
3
can be drawn out in the direction perpendicular to a sheet surface of FIG.
1
. When the sheet accommodating devices are put into their predetermined attaching positions and mounted in a main body of the printer, optical sensors (not shown) detect the mounting of each sheet supplying device and then the sheet supplying devices engage with elevator table driving gears (not shown), so that elevator tables are raised till the top surfaces of sheets stacked on the elevator tables (the upper surfaces of the elevator tables in case that there are no sheets on the elevator tables) come into contact with the paper feed rollers
20
,
21
and
22
.
Reference numeral
4
represents a photosensitive drum, which starts rotating in accordance with signals from a controller (not shown). As the photosensitive drum
4
starts rotating, a surface of the photosensitive drum
4
is uniformly charged by a corona charger (not shown). On the charged photosensitive drum
4
, an electrostatic latent image is formed by an optical system (not shown). When the electrostatic latent image reaches a position of a developing device (not shown), it is developed by toner and made visible on the photosensitive drum
2
as a toner image. The toner image thus formed by the known electrophotographic process is transferred onto the sheet fed out from a sheet tray
1
,
2
or
3
by a transfer unit
5
. Reference numeral
6
is a fixing device, by which the toner image transferred on the sheet is fixed. Reference numeral
12
is a gate member for switching directions of sheets to be transported, and
11
is a paper exhausting tray on which sheets on which images have already been formed are stacked.
Reference numeral
14
is a paper feeding passage communicating with paper supplying sections
1
,
2
and
3
; image forming means
4
,
5
, and
6
; and the paper exhausting tray
11
. Reference numeral
13
is a paper drawn-in passage, which diverges from the paper feeding passage
14
downstream in the paper transporting direction with respect to the image forming means
4
,
5
and
6
, and selectively draws the sheet fed out from the fixing device
6
therein by switching of the gate member
12
. Reference numeral
15
is a return passage which diverges from the paper drawn-in passage
13
, and of which an end joins the paper feeding passage
14
upstream in the paper transporting direction with respect to the image forming means
4
,
5
and
6
.
Accordingly, in case that printing is performed on both sides of the sheet, the sheet fed out from the fixing device
6
is drawn in the paper drawn-in passage
13
and then this sheet is fed out to the return passage
15
, whereby the sheet on which recording has been performed on one side is again fed out to the image forming means, so that two-sided recording is executed. In
FIG. 1
, reference numerals
7
and
8
are feed rollers provided before and after the gate member
12
;
9
and
10
are feed rollers, in which forward rotation and backward rotation can be switched, and their rollers
9
and
10
are provided on the paper drawn-in passage
13
; and
16
is a gate member for guiding the sheet drawn in the drawn-in passage
13
to the return passage
15
or guiding the sheet drawn in the drawn-in passage
13
again to the paper feeding passage
14
.
Next, the constitution of the sheet accommodating device will be described with reference to
FIGS. 2
,
3
and
4
.
FIG. 2
is a schematic perspective view of the sheet accommodating device
3
,
FIG. 3
is a detail view of a slide mechanism of the regulating member, and
FIG. 4
is an enlarged detail view of a lock mechanism of the regulating member.
In
FIG. 2
, reference numeral
3
represents a sheet accommodating device;
30
represents a table on which sheets are stacked;
31
represents a drive shaft attached to the sheet accommodating device;
31
a
represents a transmission gear that is engaged with an elevator table driving gear (not shown) disposed on the main body and transmits power to the drive shaft
31
;
31
b
and
31
c
represent wire drums for winding up wires that hang down the table
30
;
32
a
,
32
b
,
32
c
and
32
d
represent wires that hang down the table
30
; and
33
represents a release lever for releasing lock of the regulating members
34
and
35
.
Next, the slide mechanism of the regulating members
34
and
35
will be described with reference to FIG.
3
. To the lower portion of each of the regulating members
34
and
35
, racks
36
and
37
are attached, and to the upper portion thereof, a rack
38
is attached. In the racks
36
and
37
, the rack portions which project outside the regulating members
34
and
35
are engaged with pinions
39
rotatably supported by the sheet accommodating device
3
, while rack portions which project inside the regulating members
34
and
35
are engaged with a pinion
39
a
rotatably supported at the center of the sheet accommodating device
3
in such a manner that the rack portions use the pinion
39
a
in common. Further, in the racks
36
and
37
, pinion shafts
40
are coupled to the upper portions of the pinions
39
, and a pinions
39
disposed at the upper ends of the pinion shafts
40
are engaged with the racks
38
provided at the upper portions of the regulating members
34
and
35
.
The racks
36
and
37
are regulated in the sliding directions by guide pins
41
fixed to the sheet accommodating device
3
and can be slid only in the direction B of FIG.
2
. Guide shafts
42
provided at the upper portions of the regulating members
34
and
35
are inserted into support members
43
fixed to the sheet accommodating device
3
, and can be slid only in the direction B of FIG.
2
.
As described above, the regulating members
34
and
35
of the large size are slidably supported by the racks and the pinions in the upper portions and the lower portions thereof. Therefore, flexure is suppressed and the regulating members
34
and
35
are held firmly. Further, by sliding the release lever
33
in the direction A to release the lock, the regulating member
34
can be slid in the direction B of
FIG. 2
, so that the regulating member
35
is slid in accordance with the sliding movement of the regulating member
34
.
Next, the lock mechanism of the regulating members
34
and
35
will be described with reference to FIG.
4
. Grooves engaged with a lock pin
50
fixed to the regulating member
34
are formed in positioning plates
52
and
53
. Here, the grooves are formed respectively in the positioning plates
52
and
53
at the different position from each other. The two positioning plates are used in piles, whereby it is possible to finely set the lock position at a narrower pitch than the outer diameter of the lock pin
50
. Further, the number of the positioning plates is not limited to two, and increase of the number of the positioning plates can cause increase of the lock position. The positioning plates
52
and
53
are regulated in the sliding direction thereof by a guide pin
51
fixed to the regulating member
34
, and they are attached so that they can be slid only in the directions A and C of FIG.
2
.
Further, a tension coil springs
54
are respectively attached to the positioning plates
52
and
53
, and they give urging force by which the grooves of the positioning plates
52
and
53
are engaged with the lock pin
50
. The release lever
33
is regulated in the sliding direction thereof by a guide pin
55
attached to the regulating member
34
, and attached so that it can be slid only in the directions A and C of
FIG. 2. A
release lever rib
33
a
attached to the release lever
33
is engaged with the positioning plates
52
and
53
and moves in accordance with the slide of the release lever
33
so that it slides the positioning plates
52
and
53
in the directions A and C of
FIG. 2
, whereby engagement and disengagement between the grooves of the positioning plates
52
,
53
and the lock pin
50
are performed.
In this connection, the lock mechanism can have various designs other than the design shown in FIG.
4
. For example, as shown in
FIG. 5
, a release lever
61
is provided for the regulating member
34
and rotated by a tension coil spring
63
in the direction E of
FIG. 5
round a support pin
62
, and a groove formed in the release lever
61
is engaged with a groove forming member
60
attached to the sheet accommodating device
3
, whereby the regulating member
34
may be fixed. By rotating the release lever
61
in the direction D of
FIG. 5
, the engagement between the release lever
61
and the groove forming member
60
is released, so that the regulating member
34
can be moved in the direction B of FIG.
2
.
As described above, according to the invention, it is possible to provide a sheet accommodating device which is superior in operationality and also can position the regulating member accurately.
Claims
- 1. A sheet accommodating device comprising:a table on which a sheet is stacked; a first pinion rotatably disposed at a center of the table; a second pinion rotatably disposed on one end side of the table; a third pinion rotatably disposed on the other end side of the table; a fourth pinion connected to the second pinion and arranged above the second pinion; a fifth pinion connected to the third pinion and arranged above the third pinion; a first regulating member disposed on one side of the table, the first regulating member having a first rack portion projecting inside the first regulating member and engagable with the first pinion; a second regulating member facing the first regulating member, the second regulating member having a second rack portion engagable with the first pinion; and a lock for positioning any one of the first and second regulating members.
- 2. The sheet accommodating device as claimed in claim 1, wherein the lock comprises a positioning plate having a groove, any one of the first and second regulating members has a lock pin to be engaged with the groove of the positioning plate, and the lock pin prevents the one of the first and second regulating means from moving except for a predetermined direction.
- 3. The sheet accommodating device as claimed in claim 2, wherein the lock comprises a coil spring for engaging the lock pin with the groove of the positioning plate.
- 4. The sheet accommodating device as claimed in claim 2, wherein the lock comprises a release lever for releasing the engagement of the lock pin with the groove of the positioning plate.
- 5. The sheet accommodating device as claimed in claim 1, wherein the second regulating member is engagable with the first pinion through the second rack portion projecting inside the second regulating member.
- 6. A sheet accommodating device comprising:a table on which a sheet is stacked; a first pinion rotatably disposed within a central portion of the table; a second pinion rotatably disposed on one end side of the table; a third pinion rotatably disposed on the other end side of the table; a fourth pinion connected to the second pinion and arranged above the second pinion; a fifth pinion connected to the third pinion and arranged above the third pinion; a first regulating member disposed on one side of the table, the first regulating member having a first rack portion projecting inside the first regulating member and engagable with the first pinion; and a second regulating member facing the first regulating member, the second regulating member having a second rack portion engagable with the first pinion.
- 7. The sheet accommodating device as claimed in claim 6, wherein the second regulating member is engagable with the first pinion through the second rack portion projecting inside the second regulating member.
- 8. The sheet accommodating device as claimed in claim 7, wherein the fourth pinion is connected to the second pinion by a shaft so as to rotate with the second pinion.
- 9. The sheet accommodating device as claimed in claim 8, wherein the fifth pinion is connected to the third pinion by a shaft so as to rotate with the third pinion.
- 10. The sheet accommodating device as claimed in claim 8, further comprising a lock for locking in a position one of the first and second regulating members.
- 11. The sheet accommodating device as claimed in claim 6, wherein the first regulating member further comprises a third rack portion projecting outside the first regulating member and engaged with the fourth pinion.
- 12. The sheet accommodating device as claimed in claim 11, wherein the second regulating member further comprises a fourth rack portion projecting outside the second regulating member and engaged with the fifth pinion.
Priority Claims (1)
Number |
Date |
Country |
Kind |
11-188319 |
Jul 1999 |
JP |
|
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
5215303 |
Yamada et al. |
Jun 1993 |
|
6089566 |
Xu et al. |
Jul 2000 |
|
Foreign Referenced Citations (2)
Number |
Date |
Country |
63-258323 |
Oct 1988 |
JP |
5-294471 |
Nov 1993 |
JP |