U.S. patent number 3,883,291 [Application Number 05/417,462] was granted by the patent office on 1975-05-13 for oil applicator for reproduction machine fuser.
This patent grant is currently assigned to Xerox Corporation. Invention is credited to Eugene F. Cloutier, Douglas P. Connolly.
United States Patent |
3,883,291 |
Cloutier , et al. |
May 13, 1975 |
Oil applicator for reproduction machine fuser
Abstract
A roll-type fuser for a reproduction or copying machine where,
to obviate any tendency for the finished copy to adhere to the
fuser roll surface a liquid release material is applied thereto by
a liquid applicator. To prevent the application of excess release
material or the uneven application of the liquid material on the
fuser roll surface, a wiper, which may comprise a relatively soft
roll element, bears against the roll surface to smooth out and
remove excess liquid prior to contact of the fuser roll with the
copy material being fused. To control the amount of release
material dispensed by the applicator and, commensurate therewith,
the wiping effectiveness of the wiper, a common frame, which is
displaceable toward and away from the fuser roll, supports both the
liquid applicator and the wiper. Adjustable bias means on the frame
simultaneously controls contact pressures of both applicator and
wiper with the fuser roll so that a change in the contact pressure
of the applicator with the fuser roll with attendant change in the
amount of release material applied to the fuser roll by the
applicator effects conjointly therewith, a change in wiping ability
of the wiper.
Inventors: |
Cloutier; Eugene F. (Brighton,
NY), Connolly; Douglas P. (Webster, NY) |
Assignee: |
Xerox Corporation (Stamford,
CT)
|
Family
ID: |
23654138 |
Appl.
No.: |
05/417,462 |
Filed: |
November 19, 1973 |
Current U.S.
Class: |
432/60; 118/203;
118/60; 432/228; 399/327 |
Current CPC
Class: |
G03G
15/2025 (20130101) |
Current International
Class: |
G03G
15/20 (20060101); B05c 008/00 () |
Field of
Search: |
;432/59-60,227-228,75
;100/93RP ;219/216,388,469 ;15/4 ;401/218
;118/203,103,60,70,262,637 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Camby; John J.
Assistant Examiner: Yuen; Henry C.
Claims
What is claimed is:
1. In a reproduction machine adapted to produce copies of original
documents having a fuser for fixing the image developed on the copy
material, the fuser comprising a cooperating pressure roll and
heated fusing roll forming a fusing nip through which copies being
fused pass, the combination of:
a supply of liquid release material adapted for application to the
surface of the fusing roll to prevent the fused copy material from
adhering to the fusing roll;
applicator means in operative communication with said liquid supply
to apply said release material on said fusing roll surface;
wiper means for wiping the surface of said fusing roll to remove
excess release material and provide a uniform coating of said
release material before contact with said copy material;
bias means for biasing said applicator means and said wiper means
into pressure engagement with said fuser roll; and
bias control means for simultaneously varying pressure between said
fuser roll and both said applicator and wiper means whereby
adjustment of applicator means pressure to change the quantity of
release material applied to said fuser roll automatically changes
wiper means pressure to effect a corresponding change in the wiping
effectiveness of said wiper means.
2. The reproduction machine according to claim 1 in which said
wiper means comprises a ring-like member of relatively soft
rubber-like material.
3. The reproduction machine according to claim 1 including a
support member for both said applicator means and said wiper means,
said bias means engaging said support member to bias both said
applicator and wiper means against said fuser roll.
4. In a reproduction machine adapted to produce copies of
documents, said machine having cooperating pressure and heated
rolls for fusing images developed on the copy material, the
combination of:
applicator means to apply a liquid release material to the fuser
heated roll to prevent copies from adhering thereto,
wiper means engageable with the periphery of said fuser heated roll
to remove excess release material therefrom before contact with the
copy material being fused; and
bias means to bias both said applicator means and said wiper means
into contact with said fuser heated roller.
5. The reproduction machine according to claim 4 in which said
wiper means comprises a relatively soft rubber-like element, said
wiper element being substantially round in cross-section.
6. The reproduction machine according to claim 5 in which said
wiper element is rotatable with said fuser heated roll.
Description
This invention relates to a fusing apparatus for reproduction or
copying machines, and more particularly, to an improved roll-type
fusing apparatus incorporating means for controlling the amount of
copy release liquid applied to the fusing roll.
In order to fix, i.e. fuse, the toner developed image of the
original made by reproduction or copying machines, a fixing or
fusing apparatus, commonly termed a fuser, is provided. While the
fuser may take on many forms and types as, for example, a vapor
fuser, heat or combination heat pressure type fusers appear most
prevalent. One common type of heat-pressure fuser consists of a
heated fusing roll in operative contact with relatively soft
pressure roll. In this type of fuser, the copy material, i.e. paper
sheets, carrying a toner delineated image thereon pass between the
nip formed by the rotating fusing and pressure rolls. During this
period, heat from the fuser roll together with whatever pressure is
developed between the two rolls serves to fuse or fix the toner and
render the image permanent.
Occasionally, fusers of this type are troubled by the tendency of
the copy material to adhere or stick to the surface of the rolls,
particularly to the fusing roll itself. While the reasons for this
may be many and varied, the results of such adherence can be
serious. Usually, at the very minimum, the copy is destroyed and
the reproduction machine jammed. Occcasionally, and of more serious
nature, the trapped copy may catch fire.
To obviate any problem in this respect, the surface of the fusing
roll may, before contacting the copy, be coated with a release
material, such as a silicone based oil. This coating tends to
reduce or eliminate any tendency for the copies to stick to the
surface of the fusing roll without otherwise interfering with the
fusing ability of the fuser. However, application of such release
material must be done discretely if excessive or non-uniform
coatings are to be avoided, it being understood that too much
release material may stain the copy. And even where the quantity of
release material applied is carefully controlled, an excessive
buildup may nevertheless occur following long periods of machine
idleness, i.e. following overnight or weekend shutdown. In this
latter circumstance, the applicator itself, particularly in the
case of the rather popular sponge-type applicators, may over a long
period of idleness, accumulate excessive amounts of the release
material with the result that on first start-up of the machine, an
excessive deposit of release material is made onto the fusing roll.
This in turn carries over to the copy.
It is a principle object of the present invention to provide an
improved fusing apparatus for reproduction and copying
machines.
It is a further object of the present invention to provide an
improved system for applying release material to the fusing roll of
a roll-type fuser.
It is an object of the present invention to provide a fuser
incorporating an improved wiper mechanism for removing excess
release oil from the surface of the fusing roll prior to engagement
with the material to be fused.
It is an object of the present invention to provide an improved
wiper for controlling the amount of release liquid applied to the
fusing roll of a fuser utilizing an O-ring wiper.
It is an object of the present invention to provide a liquid
release material applying mechanism for roll-type fusers in which
both the release material applicator and wiper are supported for
conjoint adjusting movement to permit coordinated control
thereof.
This invention relates to a reproduction machine adapted to produce
copies of original documenets, the combination consisting of: a
fuser for fixing the image developed on the copy material, the
fuser including a cooperating pressure and heated fusing roll pair
forming a fusing nip through which the copies being fused pass, a
supply of liquid release material adapted for application to the
surface of the fusing roll to prevent fused copy material from
adhering to the fusing roll, applicator means in operative
communication with the release material supply to apply the release
material on the fusing roll surface, wiper means for wiping the
surface of the fusing roll to remove excess release material and
provide a uniform coating thereon before contact with the copy
material, bias means for biasing the applicator means and the wiper
means into pressure engagement with the fusing roll, and bias
control means for simultaneously varying pressure between the
fusing roll and both the applicator and wiper means whereby
adjustment of the applicator means pressure to change the quantity
of release material applied to the fusing roll automatically
changes wiper means pressure to effect a corresponding change in
the wiping effectiveness of the wiper means.
Other objects and advantages of the present invention will be
apparent from the ensuing description and drawings, in which:
FIG. 1 is a schematic view of an exemplary reproduction or copying
machine incorporating the improved fuser of the present
invention;
FIG. 2 is an enlarged cross-sectional view of the reproduction
machine fuser showing details of the fuser release material
applying and wiping mechanism of the present invention; and
FIG. 3 is a top view in section showing details of the applying and
wiping mechanism shown in FIG. 2.
Referring particularly to FIG. 1 of the drawings, an exemplary
copier/reproduction machine, designated generally by the numeral 10
and incorporating the improved fuser 38 of the present invention,
is there shown. As is all electrostatic systems such as the
xerographic type machine illustrated, a light image of a document
to be reproduced is projected onto the sensitized surface of a
xerographic plate to form an electrostatic latent image thereon.
Thereafter, the latent image is developed with an oppositely
charged developing material to form a xerographic powder or toner
image, corresponding to the latent image on the plate surface. The
toner image is then electrostatically transferred to a support
surface where it is fused by a fusing device so that the toner
image is permanently adhered to the support surface.
In machine 10, an original document 12 to be copied is placed upon
a transparent support platen 14 fixedly arranged in an illumination
assembly generally indicated by the reference numeral 15 and
disposed at the left end of the machine. While upon the platen, the
document 12 is illuminated, thereby producing image rays
corresponding to the informational areas on the original. The image
rays are projected by means of an optical system onto the
photosensitive surface of a xerographic plate. In the exemplary
copier/reproduction machine 10, the xerographic plate is in the
form of a flexible photoconductive belt 17 supported in a belt
assembly 18.
The support assembly 18 for photoconductive belt 17 includes three
rollers 20, 21, and 22 located with parallel axes at approximately
the apices of a triangle. The upper roller 22 is rotatably driven
by a suitable motor and drive means (not shown) to drive belt 17 in
the direction shown by the arrow in FIG. 1. During this movement of
the belt, the reflected light image of the original document 12 on
platen 14 is flashed upon the photoreceptor surface of belt 17 at
an exposure station 25 to produce an electrostatic latent image
thereon.
The continued movement of photoconductive belt 17 carries the
electrostatic image through a developing station 26 in which there
is positioned a developer assembly generally indicated by the
reference numeral 28. There the latent electrostatic image is
developed by means of toner through the use of a multiple magnetic
brush system 29.
The developed electrostatic image is carried by belt 17 to the
transfer station 30 where the developed image is transferred to a
support surface, normally a sheet of copy paper 31, brought forward
between transfer roller 32 and belt 17. In order to accomplish
transfer of the developed image solely by means of the electrical
bias on transfer roller 32, the copy sheet 31 is moved at
substantially the same speed as belt 17. A sheet transport
mechanism generally indicated at 34 is provided to advance copy
sheets 31 from a paper handling mechanism generally indicated by
the reference numeral 35 to transfer station 30.
Following transfer, the copy sheet 31 is stripped from belt 17 and
conveyed through fuser 38 wherein the toner image is permanently
fused or affixed thereto. Following fusing, the finished copy is
discharged into output tray 39.
Photoconductive belt 17 comprises a photoconductive layer of
selenium, which is the light receiving surface and imaging medium
for the apparatus, on a conductive backing. Further details
regarding the structure of the belt assembly 12 and its
relationship with the machine and support therefor may be found in
U.S. Pat. No. 3,730,623, issued May 1, 1973, and assigned to the
same assignee.
Referring now to FIGS. 1, 2 and 3, fuser 38 includes a suitable
housing 40 within which is disposed a lower heated fuser roll 41
and an upper back-up or pressure roll 42, rolls 41, 42 cooperating
to form a nip 43 through which the copy sheets 31 pass. Rolls 41,
42 are suitably supported for rotation and driven in unison by a
suitable drive means (not shown). Back-up roll 42 includes a rigid
internal core 64 which may be steel, for example, over which a
sleeve-like cover 65 of flexible material having non-stick
properties, such as Teflon, is disposed. The fuser roll 41
similarly has a rigid internal core 66 which may, for example, be
steel, having a relatively thick sleeve-like covering 67 thereover.
The fuser roll sleeve 67 is comprised of a flexible material, one
such material being silicon rubber. To heat fuser roll 41, a lamp
44 is disposed within the fuser roll core 66, core 66 having a
suitable opening 68 for receipt of lamp 44. In this arrangement,
heat energy from lamp 44 permeates through the metal core 66 and
outer sleeve 67 to heat the surface of roll 41 to the requisite
temperature required to fuse the toner delineated images on the
copy sheets 31. As will be understood by those skilled in the art,
other heating lamp arrangements or other heating sources may be
used instead of the arrangement illustrated.
To enhance the heating efficiency of fuser 38 and reduce any
tendency for the toner bearing sheets 31 to stick to fuser roll 41,
a suitable release material or agent is applied to the surface of
fuser roll 41. While the release material may comprise any suitable
liquid, a preferred material is silicone oil.
A supply of liquid release material 70 is held in a sump 71. Sump
71, which comprises a liquid container open at the top, is suitably
supported within fuser housing 38 in spaced relationship below
fuser roll 41. Sump 71 extends across the width of roll 41.
To raise the release material 70 up to the fuser roll 41 and apply
the material to the roll surface, a sponge-like applicator 73 is
provided which extends across the width of fuser roll 41.
Applicator 73 comprises a relatively large, generally rectangular
shaped element of a size sufficient to allow the mid-portion 74
thereof to ride against the surface of roll 41 and the trailing or
depending ends 75 thereof to rest in sump 71.
A plate-like frame member 76 serves to support both applicator 73
and, as will appear herein, wiper 95. Frame 76 is generally
rectangular and swingably supported on transverse rod 77 across the
mid portion thereof. Rod 77, which is attached to the underside of
frame member 76 by suitable means, is in turn rotatably journaled
in the opposing sides 78 of sump 71. One end 79 of frame member 76
has a pair of substantially parallel elongated slot-like openings
80, 81 therethrough, the length of which are at least equal to the
operating width of fuser roll 41. As will appear, applicator 73 for
the release material 70 is, in effect, threaded through slots 80,
81, the portion of frame member 76 between slots 80, 81 serving to
support the mid portion 74 of applicator 73 against the surface of
fuser roll 41 with the loose ends 75 of applicator 73 projecting
down from frame member 76 into the sump 71.
The opposite end 82 of frame member 76 is configured in the shape
of an elongated recess or trench which extends below and parallel
to fuser roll 41. The length of trench 82 is at least equal to and
preferably slightly greater than the operating width of fuser roll
41.
An elongated wiper support 83, the width of which is slightly less
than the width of trench 82, is slidably disposed within the trench
82 for up and down movement toward and away from fuser roll 41. The
length of wiper support 83 is at least equal to the operating width
of fuser roll 41.
To maintain applicator 73 and wiper 95 in operating contact with
the surface of fuser roll 41, springs 85 are provided at spaced
points along the length of trench 82. To prevent unwarranted
displacement of springs 85, base 86 of trench 82 has suitable
openings 87 therein through which the depending stem 92 of tension
plate 91 projects. A downwardly projecting locating rod 89,
supported from the base of wiper support 83, extends through spring
85 and tension plate 91. The lower portion of spring 85 rests
against the tension plate 91. The outer periphery of the depending
stem 92 of plate 91 is threaded, and cooperating threads (not
shown) are provided on the surface of opening 87. By this
arrangement, spring plate 91 may be selectively raised or lowered
relative to locating rod 89 to change the spring force applied
between frame member 76 and wiper support 83.
Wiper support 83 has an elongated, generally cylindrical groove 94
along the upper edge thereof opposite fuser roll 41. A generally
cylindrical wiper member 95 is disposed within slot 94, the length
of wiper 95 being at least equal to the working surface of roll 41.
It will be appreciated that the relative internal dimension of
groove 94 and the diameter of wiper 95 are chosen so as to retain
or trap wiper 95 rotatably therewithin.
Wiper 95 is preferably comprised of a relative soft rubber-like
material such as Viton and is preferably in the form of a O-ring.
Preferably, the diameter of groove 94 is slightly larger than the
diameter of wiper 95 to permit wiper 95 to turn freely
therewithin.
During use, springs 85 serve to hold both wiper 95 and applicator
73 against the surface of fuser roll 41 at a preset pressure.
During operation of fuser 38, pressure and fuser rolls 40, 41
rotate in the direction indicated by the solid line arrow in FIG.
1, the sheet 31 to be fused passing through the nip formed by the
rolls 40, 41 where the toner delineated image is fused. Following
fusing, the finished copy is deposited in output tray 39.
As fuser roll 41 turns, applicator 73, which is impregnated with
the liquid release material, wipes against the surface of roll 41
to spread or coat roll 41 with the liquid release material. The
coated surface of roll 41 is thereafter smoothed by wiper 95,
excess release material being removed therefrom and deposited in
sump 71.
The pressure with which applicator 73 and wiper 95 bear against
fuser roll 41, and hence the thickness of the coating of release
material applied to roll 41, is dependent upon the pressure with
which applicator 73 and wiper 95 bear against the roll surface. By
turning the threaded stems 92, the pressure force exerted by
springs 85 may be varied. By the construction proposed herein, any
change in spring force effects a corresponding change or adjustment
in the pressure with which both applicator 73 and wiper 95 bear
against the surface of fuser roll 41.
While the invention has been described with reference to the
structure disclosed, it is not confined to the details set forth,
but is intended to cover such modifications or changes as may come
within the scope of the following claims.
* * * * *