U.S. patent application number 12/620259 was filed with the patent office on 2010-08-19 for image forming apparatus.
This patent application is currently assigned to FUJI XEROX CO., LTD.. Invention is credited to Satoshi FUKADA, Masashi IKEDA, Go KONDO, Kouichi KUMETA, Shinji MASAKI, Masahiro MORI.
Application Number | 20100207323 12/620259 |
Document ID | / |
Family ID | 42559202 |
Filed Date | 2010-08-19 |
United States Patent
Application |
20100207323 |
Kind Code |
A1 |
KUMETA; Kouichi ; et
al. |
August 19, 2010 |
IMAGE FORMING APPARATUS
Abstract
An image forming apparatus includes: a main body; a sheet
transporting unit provided to a side portion of the main body; and
a noise source provided inside of the main body with a rotation
portion, wherein the sheet transporting unit includes a plate
having a plurality of holes, and an opposing member having a
surface opposing the plate, and wherein the noise source, the
plate, and the opposing member are disposed in the stated order
from inside of the main body to outside of the main body.
Inventors: |
KUMETA; Kouichi; (Ebina-shi,
JP) ; MORI; Masahiro; (Ebina-shi, JP) ;
FUKADA; Satoshi; (Ebina-shi, JP) ; KONDO; Go;
(Kawasaki-shi, JP) ; MASAKI; Shinji; (Ebina-shi,
JP) ; IKEDA; Masashi; (Ebina-shi, JP) |
Correspondence
Address: |
SUGHRUE MION, PLLC
2100 PENNSYLVANIA AVENUE, N.W., SUITE 800
WASHINGTON
DC
20037
US
|
Assignee: |
FUJI XEROX CO., LTD.
Tokyo
JP
|
Family ID: |
42559202 |
Appl. No.: |
12/620259 |
Filed: |
November 17, 2009 |
Current U.S.
Class: |
271/264 |
Current CPC
Class: |
B65H 2404/5214 20130101;
B65H 5/38 20130101; G03G 21/16 20130101; G03G 2215/0043 20130101;
G03G 2221/1678 20130101; G03G 15/6579 20130101; B65H 2801/06
20130101; B65H 2404/611 20130101; B65H 2601/521 20130101; B65H
2402/44 20130101 |
Class at
Publication: |
271/264 |
International
Class: |
B65H 5/00 20060101
B65H005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 17, 2009 |
JP |
2009-033847 |
Claims
1. An image forming apparatus, comprising: a main body; a sheet
transporting unit provided to a side portion of the main body; and
a noise source provided inside of the main body with a rotation
portion, wherein the sheet transporting unit includes a plate
having a plurality of holes, and an opposing member having a
surface opposing the plate, and wherein the noise source, the
plate, and the opposing member are disposed in the stated order
from inside of the main body to outside of the main body.
2. The image forming apparatus according to claim 1, wherein the
opposing member guides transporting of a sheet with the plate.
3. The image forming apparatus according to claim 1, wherein the
opposing member is a housing of the sheet transporting unit.
4. The image forming apparatus according to claim 1, wherein
expression 1 and expression 2 below are satisfied, where f denotes
a frequency of noise generated by the noise source, d denotes a
diameter of each of the holes formed in the plate, a denotes a
center-to-center distance of the holes which are next to each other
in a horizontal direction, b denotes a center-to-center distance of
the holes which are next to each other in a vertical direction, h
denotes a thickness of the plate, and g denotes a distance between
the surface of the opposing member opposing the plate and a surface
of the plate opposing the opposing member. f = C 2 .pi. .beta. ( h
+ ( .pi. / 4 ) ) g ( expression 1 ) .beta. = .pi. ( d / 2 ) 2 ab (
expression 2 ) ##EQU00002##
5. The image forming apparatus according to claim 1, wherein the
plate has a plurality of holes varying in diameter.
6. The image forming apparatus according to claim 1, wherein the
plate is disposed to enclose the noise source, and a plurality of
different distances between the surface of the opposing member
opposing the plate and the surface of the plate opposing the
opposing member are set for each portion of the plate.
7. The image forming apparatus according to claim 4, wherein the
distance between the surface of the opposing member opposing the
plate and the surface of the plate opposing the opposing member is
set based on the expression 1 and expression 2 at an intermediate
portion of the plate in a direction along a transporting direction
of the sheet, and the distance is gradually increased or decreased
with a distance from the intermediate portion in the direction
along the transporting direction of the sheet.
8. The image forming apparatus according to claim 2, wherein a
surface of the plate has a plurality of ribs protruding to a side
of a sheet and extending along a transporting direction of the
sheet, and the holes are formed between the ribs.
9. The image forming apparatus according to claim 1, wherein the
holes are each shaped to extend in a transporting direction of a
sheet.
10. The image forming apparatus according to claim 1, wherein the
holes are each formed by burring to punch the plate from a side of
the opposing member to form a beveling with a cross section of arc
on an edge portion on the side of the opposing member.
11. The image forming apparatus according to claim 1, wherein a
porous member is formed on the surface of the opposing member
opposing the plate.
12. The image forming apparatus according to claim 3, wherein the
housing covers the sheet transporting member, and the housing is
capable of opening and closing by hinging one side of the housing
with the sheet transporting unit.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and claims priority under 35
USC 119 from Japanese Patent Application No. 2009-033847 filed Feb.
17, 2009.
BACKGROUND
Technical Field
[0002] The present invention relates to an image forming
apparatus.
SUMMARY
[0003] According to an aspect of the present invention, there is
provided an image forming apparatus, including: a main body; a
sheet transporting unit provided to a side portion of the main
body; and a noise source provided inside of the main body with a
rotation portion, wherein the sheet transporting unit includes a
plate having a plurality of holes, and an opposing member having a
surface opposing the plate, and wherein the noise source, the
plate, and the opposing member are disposed in the stated order
from inside of the main body to outside of the main body.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] Exemplary embodiments of the present invention will be
described in detail based on the following figures, wherein:
[0005] FIG. 1 is a cross-sectional view of an image forming
apparatus in an exemplary embodiment of the invention;
[0006] FIG. 2 is a side cross-sectional view of a sheet
reversing/transporting mechanism in the exemplary embodiment;
[0007] FIG. 3 is a perspective view of a noise-proof mechanism in
the exemplary embodiment;
[0008] FIG. 4 is a side cross-sectional view of the noise-proof
mechanism in a first modified example of the exemplary
embodiment;
[0009] FIG. 5 is a perspective view of the noise-proof mechanism in
the first modified example of the exemplary embodiment;
[0010] FIG. 6 is a plan view of the noise-proof mechanism in a
third modified example of the exemplary embodiment;
[0011] FIG. 7 is a side cross-sectional view of the noise-proof
mechanism in a fourth modified example of the exemplary
embodiment;
[0012] FIGS. 8A and 8B are each a side cross-sectional view of the
noise-proof mechanism in a fifth modified example of the exemplary
embodiment;
[0013] FIG. 9 is a perspective view of the noise-proof mechanism in
a sixth modified example of the exemplary embodiment;
[0014] FIGS. 10A and 10B are each a plan view of the noise-proof
mechanism in a seventh modified example of the invention;
[0015] FIGS. 11A to 11C are each a diagram showing the noise-proof
mechanism in an eighth modified example of the exemplary
embodiment, and specifically, FIG. 11A is a perspective view
thereof, FIG. 11B is a perspective view thereof with a part
enlarged, and FIG. 11C is across sectional view thereof;
[0016] FIG. 12 is a side cross sectional-view of the noise-proof
mechanism in a ninth modified example of the exemplary embodiment
cut across a line XII-XII in FIG. 13B;
[0017] FIG. 13A is a side cross-sectional view of the noise-proof
mechanism in the ninth modified example of the exemplary
embodiment;
[0018] FIG. 13B is a plan view of the noise-proof mechanism of FIG.
13A;
[0019] FIG. 14 is a side cross-sectional view of the noise-proof
mechanism in a tenth modified example of the exemplary
embodiment;
[0020] FIG. 15 is another side cross-sectional view of the
noise-proof mechanism in a tenth modified example of the exemplary
embodiment, i.e., the noise-proof mechanism of FIGS. 13A and 13B
with an open external cover;
[0021] FIG. 16 is a side cross-sectional view of the noise-proof
mechanism in an eleventh modified example of the exemplary
embodiment; and
[0022] FIG. 17 is another side cross-sectional view of the
noise-proof mechanism in an eleventh modified example of the
exemplary embodiment, i.e., the noise-proof mechanism of FIG. 16
with a tilted external sheet feed tray.
DETAILED DESCRIPTION
1. Entire Configuration of Image Forming Apparatus
[0023] Now, an exemplary embodiment of the invention will be
described with reference to the accompanying drawings. A
description is first given of the entire configuration of an image
forming apparatus of this exemplary embodiment. In FIG. 1, a
reference numeral 10 denotes a main body of an image forming
apparatus A. The main body 10 includes an image forming section 20,
and the image forming section 20 includes a photosensitive drum, an
exposure section, a developing section, and others. The exposure
section serves to form an electrostatic latent image on the
photosensitive drum, and the developing section serves to develop,
using a toner, the photosensitive drum formed with the
electrostatic latent image. Above the image forming section 20, a
transfer section 30 is disposed close to the image forming section
20, and a toner image formed by the image forming section 20 is
primary-transferred to a transfer belt 31 of the transfer section
30.
[0024] In the lower portion of the main body 10, a sheet feed
section 40 is disposed. In FIG. 1, a reference numeral 41 denotes a
tray cassette for paper sheets, and paper sheets (recording sheets)
P housed in the tray cassette 41 are picked up one by one from the
top by a feed roller 42, and is conveyed by a transporting
mechanism 50.
[0025] In FIG. 1, a reference numeral 51 denotes a registration
roller, against which the tip edge end of the paper sheet P is
abutted so that the paper sheet sags between the registration
roller 51 and the feed roller 42 in the upstream. The paper sheet P
is then straightened before being conveyed. The registration roller
51 is rotated by a registration motor 52. A transfer roller 32 is
disposed downstream of the registration roller 51, and by this
transfer roller 32, the toner image on the transfer belt 31 is
secondary-transferred onto the paper sheet P.
[0026] A fixing section 60 is disposed above the transfer section
30. The toner image completed with the secondary transfer onto the
paper sheet P is fixed thereto by the heat and pressure coming from
a fixing roller 61 of the fixing section 60. Above the fixing
section 60, a sheet ejection roller 53 is disposed, which ejects
the paper sheet P through with fixing onto a sheet ejection tray
54. Note here that a reference numeral 55 in FIG. 1 denotes a
condensation prevention fan, which stirs the air therearound to
prevent condensation of the components. A reference numeral 56
denotes a sheet guide, which guides the incoming paper sheet P
toward the sheet ejection roller 53.
[0027] Next, a reference numeral 70 in FIG. 1 denotes a sheet
reversing/transporting mechanism (sheet transporting unit), which
turns over the paper sheet P completed with image formation on one
surface, thereby making the other surface of the paper sheet P
available for image formation. Such a sheet reversing/transporting
mechanism 70 is provided with a pair of sheet reversing rollers
71a. When the sheet ejection roller 53 starts rotating in the
reverse direction after feeding the paper sheet P to some point on
the way, the sheet paper P is directed onto a sheet guide 56 due to
its high degree of elasticity, thereby being conveyed to the sheet
reversing rollers 71a.
[0028] On the downstream side of the sheet reversing rollers 71a, a
reversing chute (plate) 72 is provided opposite to an opposing
reversing chute (opposing member) 73. At the center portion between
these chutes 72 and 73 in the direction of conveying the sheet and
the end portion on the downstream side, a pairs of transporting
rollers 71b and another pair of transporting rollers 71c are
respectively disposed. The pair of sheet reversing rollers 71a and
either pair of transporting rollers 71b or 71c is all driving
rollers, and the other pair of transporting rollers 71b or 71c is
driven rollers. Such driving rollers are rotated by a sheet
reversing motor 74.
[0029] The paper sheet P conveyed by the transporting rollers 71c
is directed to the transfer section 30 after going through a sheet
guide 71d. At this point in time, as to the paper sheet P, the
surface opposite to the surface already completed with image
formation is facing the transfer section 30, and onto the surface,
a toner image is secondary-transferred. The toner image as a result
of the secondary transfer onto the paper sheet P is then fixed to
the paper sheet P by the heat and pressure coming from the fixing
roller 61 of the fixing section 60. The paper sheet P is then
ejected onto the sheet ejection tray 54 by the ejection roller
53.
2. Configuration of Noise-Proof Mechanism
[0030] As shown in FIG. 2, the sheet reversing/transporting
mechanism 70 is configured as a piece of unit by an internal cover
75, and an external cover 77, i.e., the external cover 77 is
connected to the internal cover 75 so as to freely rotate by a
hinge 76. The sheet reversing/transporting mechanism 70 includes
therein the holed reversing chute 72 and the opposing reversing
chute 73, which configure the noise-proof mechanism in this
exemplary embodiment. The sheet reversing/transporting mechanism 70
is also provided therein with the sheet reversing rollers 71a, the
transporting rollers 71b and 71c, and the sheet reversing motor 74.
In this configuration, the sheet reversing motor 74 is a source of
noise. The components, i.e., the sheet reversing motor 74, the
holed reversing chute 72, and the opposing reversing chute 73, are
disposed in this order from the inside toward the outside of the
image forming apparatus A.
[0031] As shown in FIG. 3, the holed reversing chute 72 is formed
with a plurality of holes 76 at regular intervals both in the
vertical and horizontal directions. On the other hand, the opposing
reversing chute 73 is configured by a solid plate. The paper sheet
P is guided by the internal surface of the holed reversing chute 72
and that of the opposing reversing chute 73, and thus is conveyed
toward the lower portion in the drawing.
3. Operation of Image Forming Apparatus
[0032] The paper sheets P housed in the tray cassette 41 are picked
up one by one by the feed roller 42, and are then each forwarded to
the transfer section 30 by the registration roller 51 for secondary
transfer. The paper sheet P is then directed to the fixing section
60 for fixing of a toner image thereonto, and is then ejected to
the sheet ejection tray 54 by the ejection roller 53. This is the
operation for image formation onto one surface of the paper sheet
P. For image formation onto both surfaces of the paper sheet P, the
sheet ejection roller 53 is rotated in the reverse direction after
feeding the paper sheet P to some point on the way. The paper sheet
P is then directed onto the sheet guide 56 due to the high degree
of elasticity thereof, and then is conveyed toward the sheet
reversing rollers 71a. The paper sheet P is then conveyed between
the holed reversing chute 72 and the opposing reversing chute 73 by
the sheet reversing rollers 71a and the transporting rollers 71b
and 71c. After being conveyed as such, the paper sheet P reaches
the transfer section 30 after going through the sheet guide 71d,
and then is subjected to secondary transfer and fixing similarly to
the above before ejection onto the sheet ejection tray 54.
[0033] For two-sided image formation, the sheet reversing motor 74
starts rotating. When the sheet reversing motor 74 is a stepping
motor, for example, the rotation shaft thereof is of discrete
rotation in the high-frequency range, thereby resulting in a
high-frequency noise. The concern of such a sheet reversing motor
74 is that the noise thereof is easily leaked to the outside as is
disposed in the unit of the sheet reversing/transporting mechanism
70 located closer to the edge of the image forming apparatus A.
[0034] In this exemplary embodiment, the noise generated by the
sheet reversing motor 74 goes through the holes 76 formed to the
holed reversing chute 72, and then is directed to a space between
the holed reversing chute 72 and the opposing reversing chute 73.
In this space, a resonance is produced, but the noise is reduced as
is absorbed in a plurality of holes 76 formed in the holed
reversing chute 72. Moreover, because such a resonance space is not
closed, some air flow is produced therein, thereby being able to
prevent any increase of temperature and occurrence of
condensation.
[0035] Especially in the above exemplary embodiment, the
noise-proof mechanism is configured by the existing components,
i.e., the sheet reversing chutes, and one of the chutes is formed
with a plurality of holes 76. There is thus no more need to
additionally provide any new component such as noise-absorbing
member, thereby being able to reduce with effectiveness any noise
to be generated therein with no device complexity and no size
increase. Note that the noise generating source includes not only
the sheet reversing motor 74, but also the registration motor 52
and the condensation prevention fan 55. The noise to be generated
by such components can be also reduced by the noise-proof mechanism
described above.
4. Modified Example
1. First Modified Example
[0036] FIGS. 4 and 5 are each a diagram showing a first modified
example of the exemplary embodiment. In this modified example, as
an alternative to the opposing reversing chute 73, a plurality of
ribs 78 are provided to extend in the vertical direction. These
ribs 78 are disposed to the inner surface of the external cover
(housing) 77 of the sheet reversing/transporting mechanism 70
configured as a unit. With such a configuration, the paper sheet p
is guided between the holed reversing chute 72 and the ribs 78.
[0037] Also in such a modified example, the same effects as those
in the exemplary embodiment described above can be achieved, i.e.,
this modified example can achieve the noise-proof effects while
preventing any increase of temperature and occurrence of
condensation. Moreover, since the existing configuration is
utilized, i.e., a plurality of ribs 78 is provided to the inner
surface of the external cover 77, there is also no need to
additionally provide any new component. Accordingly, the device is
not complicated and not increased in size, thereby being able to
reduce with good effectiveness any noise to be generated
inside.
2. Second Modified Example
[0038] In a second modified example, various parameters are set to
satisfy the following Expressions 3 and 4, where f denotes the
frequency of a noise generated by the sheet reversing motor 74, d
denotes the diameter of each of the holes 76 formed in the holed
reversing chute 72, a and b respectively denote the
center-to-center distance between any adjacent holes 76 in the
horizontal and vertical directions, h denotes the thickness of the
holed reversing chute 72, and g denotes the distance between the
holed reversing chute 72 and the opposing reversing chute 73 from
one surface to the surface opposing thereto.
f = C 2 .pi. .beta. ( h + ( .pi. / 4 ) ) g ( expression 3 ) .beta.
= .pi. ( d / 2 ) 2 ab ( expression 4 ) ##EQU00001##
[0039] The above Expression 3 is about requirements for attenuating
noise in the frequency range of f with most effectiveness. In this
modified example, by setting the parameters described above in
accordance with the frequency range of a noise to be generated by
the noise source, the resulting noise-proof effects can be enhanced
to maximum.
3. Third Modified Example
[0040] FIG. 6 is a diagram showing a third modified example of the
exemplary embodiment. In this modified example, the holed reversing
chute 72 is formed with large-diameter holes 76a and small-diameter
holes 76b in an alternate manner. The large-diameter holes 76a
serve to absorb any noise in the high frequency range, and the
small-diameter holes 76b serves to absorb any noise in the low
frequency range. Accordingly, in this modified example, even when
the reversing motor 74 is set to two values of rotation frequency
for high-speed operation and normal operation, the noise-proof
effects remain high with both operation speeds.
4. Fourth Modified Example
[0041] FIG. 7 is a diagram showing a fourth modified example of the
exemplary embodiment. In this modified example, a holed reversing
chute 80 is configured to include a vertical plate portion 80a, a
tilted plate portion 80b, and a horizontal plate portion 80c. The
vertical plate portion 80a extends in the vertical direction, and
the tilted plate portion 80b extends from the upper end of the
vertical plate portion 80a to diagonally inward, i.e., toward the
inside of the main body 10. The horizontal plate portion 80c
extends from the upper end of the tilted plate portion 80b in the
horizontal direction. With such a configuration, the holed
reversing chute 80 partially encloses the sheet reversing motor 74.
Opposing to such a holed reversing chute 80, an opposing reversing
chute 81 is disposed, which is configured to include a vertical
plate portion 81a, a tilted plate portion 81b, and a horizontal
plate portion 81c. The vertical plate portion 81a extends in the
vertical direction, and the tilted plate portion 81b extends from
the upper end of the vertical plate portion 81a to diagonally
inward. The horizontal plate portion 81c extends from the upper end
of the tilted plate portion 81b in the horizontal direction.
[0042] A space A is formed between the vertical plate portion 80a
of the holed reversing chute 80 and the vertical plate portion 81a
of the opposing reversing chute 81, and a space B is formed between
each of the tilted plate portion 80b and the horizontal plate
portion 80c and each of the tilted plate portion 81b and the
horizontal plate portion 81c. The space B is smaller than the space
A. That is, the parameter "g" in the Expression 2 corresponds to
the spaces A and B, and thus the portion with the space A is lower
in frequency than the portion with the space B. As such, in this
modified example, the portion with the space A absorbs any noise in
the low frequency range, and the portion with the space B absorbs
any noise in the high frequency range. Therefore, even when the
sheet reversing motor 74 is set to two values of rotation frequency
for high-speed operation and normal operation, the resulting
noise-proof effects remain high with the both operation speeds.
What is better, any possible noise leakage can be prevented with
good effectiveness because these chutes, i.e., the holed reversing
chute 80 and the opposing reversing chute 81, are enclosing around
the sheet reversing motor 74.
5. Fifth Modified Example
[0043] FIGS. 8A and 8B are each a diagram showing a fifth modified
example of the exemplary embodiment. The holed reversing chute 72
and the opposing reversing chute 73 in the exemplary embodiment are
extending in the vertical direction to be parallel to each other as
schematically shown in FIG. 8A. In this modified example, on the
other hand, a holed reversing chute 82 remains to extend in the
vertical direction. However, an opposing reversing chute 83 is bent
at the center portion, and the space C with the holed reversing
chute 82 is minimized at the center portion. With such a
configuration, the space between the holed reversing chute 82 and
the opposing reversing chute 83 is gradually increased in the
direction of moving away from each other, i.e., from the center
portion in the vertical direction. The space C is set based on the
above Expression 2.
[0044] In this modified example, because the space Cis set in
accordance with the rated operation speed of the image forming
apparatus A, with the normal operation, the noise-proof effects can
be enhanced to maximum at the portion with the space C. When the
operation speed is slowed down due to some reasons, the other
portion not including the portion with the space C can
satisfactorily enhance the noise-proof effects. That is, in this
modified example, because the parameter "g" in the Expression 2
shows a sequential change, even if the noise frequency is reduced
due to the unexpected reduction of the operation speed, the
noise-proof effects remain high. Note that, in this modified
example, the space between the holed reversing chute 82 and the
opposing reversing chute 83 may be so set as to be gradually
reduced in the direction of moving away from each other, i.e., from
the center portion in the vertical direction.
6. Sixth Modified Example
[0045] FIG. 9 is a diagram showing a sixth modified example of the
exemplary embodiment. In this modified example, a holed reversing
chute 84 is formed with a plurality of ribs 85 on the surface on
the side of the opposing reversing chute. The ribs 85 are each
extending to protrude toward the side of the opposing reversing
chute along the direction of conveying the paper sheet P, i.e.,
vertical direction. The portion of the holed reversing chute 84
where such ribs 85 are not provided is formed with a plurality of
holes 76 at regular intervals both in the vertical and horizontal
directions.
[0046] In this modified example, alternatively, the paper sheet P
to be conveyed may be guided by the ribs 85 to reduce any possible
resistance during transporting. Herein, the ribs 85 may be provided
to the opposing reversing chute.
7. Seventh Modified Example
[0047] FIG. 10 is a diagram showing a seventh modified example of
the exemplary embodiment. In this modified example, as shown in
FIG. 10A, as alternatives to the ribs 85, the holed reversing chute
72 may be formed with an oblong or oval hole 86 in the direction of
conveying of the paper sheet P, or as shown in FIG. 10B, the holed
reversing chute 72 may be formed with a rhombus hole 87 extending
in the direction of conveying of the paper sheet P. In such a
modified example, the paper sheet P does not contact with the hole
86 (87) that much when being in contact with the holed reversing
chute 72, thereby being able to reduce the resistance
therewith.
8. Eighth Modified Example
[0048] FIGS. 11A to 11C are each a diagram showing an eighth
modified example of the exemplary embodiment. In this modified
example, holes 88 are each formed by burring to punch the holed
reversing chute 72 from the side of the opposing reversing chute
73. Accordingly, at an edge portion of the holed reversing chute 72
on the side of the opposing reversing chute 73, a beveling R is
formed with a cross section of arc.
[0049] In this modified example, since the paper sheet P contacts
with the beveling R of each of the holes 88, the contact becomes
smooth, thereby reducing the resistance.
9. Ninth Modified Example
[0050] FIGS. 12 to 13B are each a diagram showing a ninth modified
example of the exemplary embodiment. As shown in these drawings, an
opposing reversing chute 90 is formed with a plurality of ribs 91
on the surface opposing the holed reversing chute 72. The ribs 91
are extending along the direction of conveying the paper sheet P,
i.e., vertical direction, and are formed in two clusters separated
in the vertical direction. In the upper cluster, a porous member 92
such as cork is provided not to cover the ribs 91. In such a
modified example, any moisture evaporated from the paper sheet P is
absorbed by the porous member 92, thereby being able to suppress
any occurrence of condensation with good effectiveness.
10. Tenth Modified Example
[0051] FIG. 14 is a diagram showing a tenth modified example of the
exemplary embodiment. In this modified example, in the first
modified example described by referring to FIGS. 4 and 5, the
external cover 77 is attached to the main body 10 using a hinge 93
so as to freely rotate. In this modified example, the external
cover 77 is configured to freely open and close as such, thereby
easing the maintenance and inspection of the noise-proof mechanism
configured by the holed reversing chute 72 and others.
11. Eleventh Modified Example
[0052] FIGS. 16 and 17 are each a diagram showing an eleventh
modified example of the exemplary embodiment. In this modified
example, the main body 10 is provided with an external sheet feed
tray 100. This external sheet feed tray 100 is configured to
include a tray body 101, and an auxiliary tray 102. The auxiliary
tray 102 is attached to the tray body 101 to be able to be pulled
out therefrom. As shown in FIG. 17, when such an external sheet
feed tray 100 is in use, it is tilted by a hinge mechanism that is
not shown, and the auxiliary tray 102 is pulled out from the tray
body 101 for use with the paper sheets P placed thereon.
[0053] In such a modified example, a lattice-like louver 103 (not
shown) is formed on the left side surface of the main body, and the
air is ejected from the apertures of the lattice-like louver. As a
result, any noise to be generated in the main body 10 is also
leaked from the apertures. For solving such a problem, in this
modified example, the external sheet feed tray 100 is provided with
a noise-proof mechanism. That is, in the tray body 101, a plate
101a on the side of the main body 10 is formed with a plurality of
holes, and the auxiliary tray 102 serves as an opposing component.
In the state of FIG. 16, the noise leaked from the main body 10
goes through the holes and then enters into the space formed by the
plate 101a and the auxiliary tray 102, thereby being reduced after
being absorbed by the holes.
[0054] Note that, in the state of FIG. 16, as an alternative
configuration, the auxiliary tray 102 may be pulled out for use. If
this is the configuration, the plates 101a and 101b on the both
sides of the tray body 101 form a space so that the resulting space
is wider in width. Accordingly, any noise in the lower frequency
range can be absorbed.
[0055] While the invention has been described in detail, it is
understood that numerous other modifications and variations can be
devised. For example, in the third modified example of FIG. 6, the
holes are assumed as varying in diameter, i.e., two diameter sizes
of large and small. Alternatively, three or more diameter sizes
will allow to deal with a larger range of frequency. Moreover, in
the eighth modified example of FIG. 11, the holes are formed by
fluing. This is surely not restrictive, and the holes may be formed
by normal press punching, and the space between each of the punched
portions and a die may be set larger. If this is the case, the
resulting holes can be each formed with a beveling R with a cross
section of arc.
[0056] The invention can be applied to an image forming apparatus
such as copier, printer, facsimile device, and a multi-function
device serving all of these.
[0057] The foregoing description of the exemplary embodiments of
the present invention has been provided for the purposes of
illustration and description. It is not intended to be exhaustive
or to limit the invention to the precise forms disclosed.
Obviously, many modifications and variations will be apparent to
practitioners skilled in the art. The embodiments were chosen and
described in order to best explain the skilled in the art to
understand the invention for various embodiments and with the
various modifications as are suited to the particular use
contemplated. It is intended that the scope of the invention be
defined by the following claims and their equivalents.
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