U.S. patent application number 12/585806 was filed with the patent office on 2010-04-15 for sealing device.
This patent application is currently assigned to Uchiyama Manufacturing Corp.. Invention is credited to Chihiro Asanuma, Koki Ishida, Tadashi Kasamoto, Tatsuo Katayama, Yoshihiko Yamaguchi, Hironori Yamamoto.
Application Number | 20100090411 12/585806 |
Document ID | / |
Family ID | 41795283 |
Filed Date | 2010-04-15 |
United States Patent
Application |
20100090411 |
Kind Code |
A1 |
Yamamoto; Hironori ; et
al. |
April 15, 2010 |
Sealing device
Abstract
A sealing device for sealing a space between a rotary side
member and a stationary side member which comprises a slinger with
a specific structure is disclosed. The sealing device comprises a
slinger fixedly fitted to a rotary side member, a core member
fixedly fitted to a stationary side member, and an elastic sealing
member fixed to the core member and having a seal lip which
elastically and slidably contacts the slinger in which the slinger
is characterized by comprising a fitting cylindrical portion to be
fitted into said rotary side member, a brim portion extending its
radial direction at one end of its outside relative to a sealed
portion of the fitting cylindrical portion, and a rotary side
fixing member fixed to the brim portion; and further characterized
by being made in such a manner that an adhesive layer is formed on
its whole surface including a contacting side surface where said
seal lip contacts by applying adhesive agent thereon, then the
fixing member is integrally fixed thereto, thereafter the adhesive
layer is partially removed only in the contacting side surface.
Inventors: |
Yamamoto; Hironori;
(Okayama, JP) ; Ishida; Koki; (Okayama, JP)
; Katayama; Tatsuo; (Okayama, JP) ; Kasamoto;
Tadashi; (Okayama, JP) ; Yamaguchi; Yoshihiko;
(Okayama, JP) ; Asanuma; Chihiro; (Okayama,
JP) |
Correspondence
Address: |
BACON & THOMAS, PLLC
625 SLATERS LANE, FOURTH FLOOR
ALEXANDRIA
VA
22314-1176
US
|
Assignee: |
Uchiyama Manufacturing
Corp.
Okayama
JP
|
Family ID: |
41795283 |
Appl. No.: |
12/585806 |
Filed: |
September 25, 2009 |
Current U.S.
Class: |
277/351 |
Current CPC
Class: |
F16C 33/7883 20130101;
F16C 2326/02 20130101; Y10T 156/10 20150115; F16C 41/007 20130101;
F16C 19/186 20130101 |
Class at
Publication: |
277/351 |
International
Class: |
F16J 15/32 20060101
F16J015/32; F16J 15/44 20060101 F16J015/44 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 1, 2008 |
JP |
2008-256506 |
Aug 7, 2009 |
JP |
2009-184900 |
Claims
1. A sealing device having a slinger fixedly fitted to a rotary
side member, a core member fixedly fitted to a stationary side
member, and an elastic sealing member fixed to the core member and
having a seal lip which elastically and slidably contacts the
slinger, said sealing device sealing a space between said rotary
side member and said stationary side member, wherein: said slinger
comprises a fitting cylindrical portion to be fitted into said
rotary side member, a brim portion extending its radial direction
at one end of its outside relative to a sealed portion of said
fitting cylindrical portion, and a rotary side fixing member fixed
to said brim portion; and wherein said slinger is made in such a
manner that an adhesive layer is formed on its whole surface
including a contacting side surface where said seal lip contacts by
applying adhesive agent thereon, then said fixing member is
integrally fixed thereto, thereafter said adhesive layer is
partially removed only in said contacting side surface.
2. A sealing device having a slinger fixedly fitted to a rotary
side member, a core member fixedly fitted to a stationary side
member, and an elastic sealing member fixed to the core member and
having a seal lip which elastically and slidably contacts the
slinger, said sealing device sealing a space between said rotary
side member and said stationary side member, wherein: said slinger
comprises a fitting cylindrical portion to be fitted into said
rotary side member, a brim portion extending in its radial
direction at one end of outside relative to a sealed portion of
said fitting cylindrical portion, said end being outside relative
to a sealed portion, and a rotary side fixing member fixed to said
brim portion; and wherein said slinger is made in such a manner
that an adhesive layer is formed on its whole surface including a
contacting side surface where said seal lip contacts by applying
adhesive agent thereon, then said adhesive layer is partially
removed only in said contacting side surface and thereafter said
fixing member is integrally fixed thereto.
3. The sealing device as set forth in claim 1, wherein said
adhesive layer is partially removed only in said contacting side
surface by way of laser emission treatment.
4. The sealing device as set forth in claim 1, wherein said
contacting side surface is formed such that said adhesive layer is
removed and surface roughening finishing is treated thereon.
5. A sealing device having a slinger fixedly fitted to a rotary
side member, a core member fixedly fitted to a stationary side
member, and an elastic sealing member fixed to the core member and
having a seal lip which elastically and slidably contacts the
slinger, said sealing device sealing a space between said rotary
side member and said stationary side member, wherein: said slinger
comprises a fitting cylindrical portion to be fitted into said
rotary side member, a brim portion extending its radial direction
at one end of its outside relative to a sealed portion of said
fitting cylindrical portion, and a rotary side fixing member fixed
to said brim portion; and wherein said slinger is made in such a
manner that an adhesive layer is formed on its whole surface by
applying adhesive agent thereon, then said fixing member is
integrally fixed thereto with a part of said adhesive layer,
thereafter other member is provided on a surface where said seal
lip contacts, thereby constituting a contacting surface relative to
said seal lip.
6. The sealing device as set forth in claim 5, wherein a surface
roughening finishing is treated on said contacting surface relative
to said seal lip.
7. The sealing device as set forth in claim 2, wherein said
adhesive layer is partially removed only in said contacting side
surface by way of laser emission treatment.
8. The sealing device as set forth in claim 2, wherein said
contacting side surface is formed such that said adhesive layer is
removed and surface roughening finishing is treated thereon.
9. The sealing device as set forth in claim 3, wherein said
contacting side surface is formed such that said adhesive layer is
removed and surface roughening finishing is treated thereon.
10. The sealing device as set forth in claim 7, wherein said
contacting side surface is formed such that said adhesive layer is
removed and surface roughening finishing is treated thereon.
Description
TECHNICAL FIELD
[0001] The present invention relates to a sealing device interposed
in a portion required to be sealed between a stationary side member
and a rotary side member such as a bearing unit in the wheel
suspension of automobile, more specifically to a sealing device
having a slinger fixedly fitted to a rotary side member, a core
member fixedly fitted to a stationary side member, and an elastic
sealing member which is fixed to the core member and elastically
and slidably contacts the slinger, whereby sealing a space between
the rotary side member and the stationary side member.
BACKGROUND ART
[0002] A sealing device has been well known which is interposed
between a stationary side member and a rotary side member like a
bearing unit in the wheel suspension device of automobile in order
to prevent water and dust from entering.
[0003] Several measures have been recently taken so as to realize
fuel efficient vehicles and the reduction of rotary torque is
sought for the bearing unit.
[0004] In order to reduce the friction force with the sealing
member, the slidably contacting surface of the sealing member fixed
to the core member with the slinger (referred to slidably
contacting surface hereinafter) is executed with surface treatment
or other member is interposed between the slidably contacting
surface.
[0005] The following patent citations 1 (Japanese Patent
Publication, H11-190351-A) and 2 (Japanese Patent Publication,
2003-262231-A) disclose that the slidably contacting surface is
treated with some surface treatment.
[0006] The patent citation 1 describes a sealing member wherein a
nitride layer or a nitrosulphurizing layer is formed on the
slidably contacting surface in a condition that surface oxide is
removed, and accordingly the outer surface can be reformed to have
fine, flat and hard surface nature while thermal strain of a base
material is restrained during formation of the layer. It describes
that, as the result, the frictional coefficient of the sliding part
of the sealing member becomes low and heat generation can be
restrained even though oil film is consumed.
[0007] The patent citation 2 describes a seal for roller bearing
wherein the slidably contacting surface is executed with hardening
treatment or applied with a hard film having corrosion resistance
and a rust-prevention property. It describes that, as the result,
anti-abrasive wearing ability and anti-corrosion wearing ability
are improved on the slidably contacting surface under the
circumstances of dirty salt water, thereby reducing the wearing
amount on the metal surface and improving the sealing ability and
the sealing durability.
[0008] The patent citation 3 (Japanese Patent Publication,
H09-79274-A) is an embodiment in which other member is interposed
between the sealing member and the slidably contacting surface.
[0009] The patent citation 3 describes an oil seal device in which
a heat shrinking tube is fitted to the peripheral surface of a
rotary side member and a sealing member comes into sliding contact
by a fixed margin with a smooth surface of the tube. It describes
that, as the result, wearing of the sealing member can be
remarkably reduced by utilizing the lubricity of the heat shrinking
tube.
DISCLOSURE OF INVENTION
Problems to be Solved in the Invention
[0010] A sealing device may have a tone wheel made of a circular
multipolar magnet at the outer surface of a slinger or have a seal
lip on the slinger side in addition to the core member side.
According to such a sealing device, the tone wheel or the seal lip
is integrally stuck to the slinger with an adhesive agent and it is
preferable that the adhesive agent is applied all over the sticking
surface and it is strongly adhered to the slinger.
[0011] However, it may be difficult that the adhesive agent is
applied to every end of the tone wheel and the seal lip depending
on their shape.
[0012] Accordingly, the slinger is entirely dipped in the adhesive
agent prepared in a vessel and thereafter the tone wheel or a seal
lip at slinger side is attached.
[0013] In such a case, even if the slidably contacting surface is
executed with surface treatment like the patent citations 1 and 2,
an adhesive layer is formed on the surface treated slidably
contacting surface by the adhesive agent. Therefore, there is a
problem that the reduction effect of the rotary torque is
deteriorated even if surface treatment is executed.
[0014] Further, according to the patent citation 3, the slinger to
be fixedly fitted to the rotary side member is not expected, so
that such a device cannot be used for a sealing device in which a
tone wheel or a seal lip is stuck to the slinger.
[0015] The present invention is proposed in view of the
above-mentioned problems and it provides a sealing device in which
a fixing member to be fixed to the slinger is strongly adhered and
the rotary torque can be reduced.
Means to Solve Problems
[0016] According to the present invention proposed to achieve the
above-mentioned objects, the sealing device has a slinger fixedly
fitted to a rotary side member, a core member fixedly fitted to a
stationary side member, and an elastic sealing member fixed to the
core member and having a seal lip which elastically and slidably
contacts the slinger, the sealing device sealing a space between
the rotary side member and the stationary side member. The slinger
comprises a fitting cylindrical portion to be fitted into the
rotary side member, a brim portion extending its radial direction
at one end of its outside relative to a sealed portion of the
fitting cylindrical portion, and a rotary side fixing member fixed
to the brim portion, and the slinger is made in such a manner that
an adhesive layer is formed on its whole surface including a
contacting side surface where the seal lip contacts by applying
adhesive agent thereon, then the fixing member is integrally fixed
thereto, thereafter the adhesive layer is partially removed only in
the contacting side surface.
[0017] According to the sealing device of the present invention,
the slinger may be made in such a manner that an adhesive layer is
formed on its whole surface including a contacting side surface
where the seal lip contacts by applying adhesive agent thereon,
then the adhesive layer is partially removed only in the contacting
side surface and thereafter the fixing member is integrally fixed
thereto.
[0018] In the present invention, the adhesive layer may be
partially removed only in the contacting side surface by way of
laser emission treatment.
[0019] In addition, a physical method of removing the adhesive
layer includes a shot peening treatment and a shot blast treatment.
Further, as a chemical method, an adhesive removal liquid may be
used depending on the component of adhesive agent.
[0020] Further according to the present invention, the contacting
side surface may be formed such that the adhesive layer is removed
and surface roughening finishing is treated thereon.
[0021] According to the present invention, the slinger may comprise
a fitting cylindrical portion to be fitted into the rotary side
member, a brim portion extending its radial direction at one end of
its outside relative to a sealed portion of the fitting cylindrical
portion, and a rotary side fixing member fixed to the brim portion,
and the slinger may be made in such a manner that an adhesive layer
is formed on its whole surface by applying adhesive agent thereon,
then the fixing member is integrally fixed thereto with a part of
the adhesive layer, thereafter other member is provided on a
surface where the seal lip contacts, thereby constituting a
contacting surface relative to the seal lip.
[0022] In this case, a surface roughening finishing may be treated
on the contacting surface relative to the seal lip. Material of the
other member is not limited, however, it includes a metal material,
a synthetic resin material like engineering plastic, ceramics,
glass, industrial diamond, a resin material with low friction,
elastomer and so on.
ADVANTAGEOUS EFFECTS
[0023] According to the sealing device of the present invention,
after an adhesive agent is applied on the whole surface of the
slinger and the fixing member is integrally stuck to the slinger,
the adhesive layer formed on the slidably contacting surface of the
slinger with the seal lip is removed. Therefore, the adhesive layer
is not formed on the slidably contacting surface of the slinger
with the seal lip, so that the friction resistance of the seal lip
can be reduced, thereby reducing the rotary torque.
[0024] Further, even when after the adhesive agent is applied on
the whole surface of the slinger and only the adhesive layer formed
on the slidably contacting surface of the slinger with the seal lip
is removed, the fixing member is integrally stuck to the slinger,
the adhesive layer is not formed on the slidably contacting surface
with the seal lip. Therefore, the friction resistance of the seal
lip can be reduced, thereby achieving reduction of the rotary
torque.
[0025] Accordingly, when the sealing device of the present
invention is used for the bearing unit of vehicle, fuel-efficiency
can be achieved. Further, the whole sticking surface of the fixing
member is filled with the adhesive agent applied on the whole
surface of the slinger, so that the adhesive agent is spread over
every end of the fixing member and the fixing member can be firmly
adhered to the slinger.
[0026] In the present invention, if removal of the adhesive layer
on the slidably contacting surface of the slinger with the seal lip
is executed by a laser treatment, an uneven surface without having
edges can be easily formed, thereby more effectively reducing the
friction resistance on the slidably contacting surface.
[0027] Further in case of a laser treatment, even if the surface to
be treated is formed like a ring and its area is very small, an
exact and effective removal treatment can be done at the surface
(slidably contacting surface) to be treated. In addition, according
to the laser treatment, the degree of treatment can be easily
controlled depending on the characteristic of the material of the
slinger and the thickness of the adhesive layer.
[0028] According to the present invention, when the slidably
contacting surface is treated to be roughened in addition to the
removal treatment of the adhesive layer on the slidably contacting
surface, removal of the adhesive layer and roughening of the
slidably contacting surface can be done by one procedure, so that
the roughened surface can further reduce the friction resistance of
the seal lip, thereby remarkably reducing the rotary torque.
[0029] When the other member is interposed between the slidably
contacting surface of the slinger with the seal lip to constitute a
slidably contacting surface, the seal lip slidably contacts with
the other member. Therefore, the adhesive layer is not provided on
the slidably contacting surface of the seal lip, so that the
friction resistance of the seal lip can be reduced, thereby
achieving reduction of the rotary torque. When the sealing device
of the present invention is used for the bearing unit of vehicle,
fuel-efficiency can be achieved
[0030] Also in this case, the whole sticking surface of the fixing
member is filled with the adhesive agent applied on the whole
surface of the slinger, so that every end of the fixing member is
applied with the adhesive agent and the fixing member can be firmly
adhered to the slinger.
[0031] Further, when the slidably contacting surface is treated to
be roughened, the friction resistance of the seal lip can be
further reduced, thereby remarkably reducing the rotary torque.
BRIEF DESCRIPTION OF DRAWINGS
[0032] FIG. 1 is a longitudinal sectional view showing the first
embodiment in which the sealing device of the present invention is
employed for the bearing unit.
[0033] FIG. 2 is an enlarged view of the portion "X" in FIG. 1.
[0034] FIG. 3a to FIG. 3c are diagrammatical sectional views
showing one example of the production procedures of the sealing
device of the first embodiment.
[0035] FIG. 4a to FIG. 4c are diagrammatical sectional views
showing the production procedures of the sealing device different
from the embodiment in FIG. 3.
[0036] FIG. 5 shows a modified embodiment of the sealing device of
the first embodiment and is a similar view to FIG. 2.
[0037] FIG. 6 shows the second embodiment of the sealing device of
the present invention and corresponds to the enlarged view of "X"
in FIG. 1.
[0038] FIG. 7 is a diagrammatical sectional view showing the
production procedure of the second embodiment.
[0039] FIG. 8 shows a modified embodiment of the sealing device of
the second embodiment and is a similar view to FIG. 2.
BEST MODE FOR CARRYING OUT THE INVENTION
[0040] The embodiment of the present invention is explained
referring to the drawings.
[0041] The first embodiment of the present invention is explained
at first referring to FIG. 1 to FIG. 5
[0042] Example in which a tone wheel 70 is used as a fixing member
to be fixed to the slinger 7 of the sealing device 6 (refer to FIG.
1 to FIG. 4) and an example in which a rotary side seal lip 11 is
used (refer to FIG. 5) are explained.
[0043] FIG. 1 shows one example of the structure which supports
vehicle wheels relative to a driving shaft 2 by a bearing unit 1. A
tire wheel (not shown) is fixed to a hub 3 constituting an inner
ring with a bolt 31. The reference numeral 32 indicates a spline
hole formed in the hub 3 and the driving shaft 2 is spline fitted
in the spline hole 32 to be integrally fixed to the hub 3, thereby
transmitting the rotary drive force of the driving shaft 2 into the
tire wheel. The reference numeral 33 indicates an inner ring member
and constitutes the inner ring together with the hub 3.
[0044] The reference numeral 4 indicates an outer ring and is
fixedly fitted to the vehicle suspension (not shown). Two rows of
rolling elements (ball) 5 . . . are interposed while being held
with a retainer 51 between the outer ring 4 and the inner ring (hub
3 and inner ring member 33). The reference numeral 6 indicates a
sealing device for preventing leakage of lubricant agent (grease
and the like) provided in the rolling portion of the rolling
elements 5 . . . and for preventing ingress of dirt or water from
outside and is inserted under pressure between the outer ring 4 and
the inner ring (hub 3 and inner ring member 33). The sealing device
6 provided at the vehicle side has a tone wheel 70 made of a
circular multipolar magnet. The portion enclosed with the sealing
device 6, the inner ring (hub 3 and inner ring member 33) and the
outer ring 4 constitutes a sealed portion S.
[0045] FIG. 2 is an enlarged view of the portion "X" in FIG. 1 in
which a ring-like slinger 7 obtained by sheet metal processing of
stainless steel (SUS430 and the like) is externally fitted into the
peripheral body at the inner ring side (hub 3 and inner ring member
33). The slinger 7 comprises a fitting cylindrical portion 71
fitted to the peripheral body of the inner ring (hub 3 and inner
ring member 33) and a brim portion 72 radially extended at an end
of the fitting cylindrical portion 71, which is opposite to a
sealed portion S.
[0046] A ring-like core member 80 obtained by sheet metal
processing of stainless steel (SUS430) is externally fitted into
the peripheral body (inner peripheral surface) at the outer ring 4
side. The core member 80 comprises a cylindrical portion 80a
fixedly fitted to the peripheral body of the outer ring 4 and an
inward brim portion 80b connected to an end of the cylindrical
portion 80a. And the core member 80 is fixed with a sealing member
8 made of a rubber material selected from NBR, H-NBR, ACM, AEM, FKM
and the like. The sealing member 8 comprises a lip body 81 made of
an elastic material such as rubber integrally formed with the core
member 80 and the lip body 81 includes a plurality of seal lips 82
. . . extending like a tongue. When the slinger 7 and the core
member 80 with the sealing member 8 are fitted and combined each
other to constitute the sealing device 6, the tip ends of the seal
lips 82 . . . elastically and slidably contact the surface of the
slinger 7 accompanied with elastic deformation. The reference
numeral 73 in the figure shows a slidably contacting surface of the
slinger 7 with the seal lip 82.
[0047] The tone wheel 70 which is made of a circular multipolar
magnet on which a plurality of N poles and S poles are alternately
provided along the circumferential direction to be magnetized is
integrally stuck on the outer surface 74 (at vehicle side) of the
brim portion 72 of the slinger 7 relative to the sealed portion
S.
[0048] A magnetic sensor 10 is fixedly provided for the outer ring
4 or the stationary side member of the vehicle and constitutes a
magnetic encoder E together with the tone wheel 70 for detecting
the rotary speed of the tire wheel. The tone wheel 70 is made of a
magnetic rubber sheet in which magnetic powder such as ferrite or
rare earth is mixed in advance with a rubber material selected from
NBR, H-NBR, ACM, AEM, FKM and the like and is magnetized by
arranging a plurality of N poles and S poles alternately in the
circumferential direction. The tone wheel 9 may not be limited to
be made of the above magnetic rubber, but may be a plastic magnet
or a sintered magnet.
[0049] The tone wheel 70 is integrally fixed to the outer surface
74 of the brim portion 72 of the slinger 7 with adhesive. The
reference numeral 75 in the figure indicates an adhesive layer
formed with an adhesive agent. The adhesive agent is preferably an
epoxy-based adhesive or a phenolic adhesive, however, it may be an
elastic adhesive such as sealant or elastomeric adhesive.
[0050] Thus the sealing device 6 having the tone wheel 70 is
constituted with the slinger 7, the core member 80, the sealing
member 8 and the tone wheel 70. The slidably contacting surface 73
of the slinger 7 to which the seal lips 82 elastically contact
becomes a sealing surface on which they slidably contact each other
accompanied with rotation of the inner ring (hub 3 and inner ring
member 33), thereby preventing invasion of dirt or water into the
bearing unit 1 from outside and leakage of grease and the like
filled in the bearing unit 1. In the figure, three seal lips 82
which slidably contact the fitting cylindrical portion 71 and the
brim portion 72 of the slinger 7 are formed, however, the shape of
seal lip 82 is not limited to the embodiment in the figure. The
slidably contacting surface 73 may be applied with grease of ester,
synthetic hydrocarbon or mineral oil.
[0051] The enlarged view of the portion "Y" in FIG. 2
diagrammatically shows how the slidably contacting surface 73 is
formed.
[0052] The slidably contacting surface 73 of the slinger 7 with the
seal lip 82 as shown in the enlarged view of "Y" portion is
processed with roughening treatment in addition to removal of the
adhesive layer 75 for adhering the tone wheel 70.
[0053] Because the adhesive layer 75 is removed, the slidably
contacting surface 73 of the slinger 7 with the seal lip 82 is not
provided with the adhesive layer 75, so that the friction
resistance of the seal lip 82 can be reduced and the rotary torque
can be also reduced.
[0054] When grease is applied on the slidably contacting surface 73
with roughening treatment, it can be kept thereon for a long time,
thereby more effectively improving the sealing ability and reducing
the friction resistance.
[0055] In addition, it is made uneven surface without edges as
shown in the enlarged view of the portion "Y" in FIG. 2, the
friction resistance of the slidably contacting surface 73 can be
more effectively reduced.
[0056] A method for removing the adhesive layer 75 or a method for
removing the adhesive layer 75 and for executing roughening
treatment includes a laser treatment, a shot peening treatment, a
shot blast treatment, and the like.
[0057] Here a laser treatment and a shot peening treatment are
detailed.
(Laser Treatment)
[0058] The following conditions are employed for a laser treatment
for removing the adhesive layer 75.
[0059] The kinds of laser to be used are not specifically limited,
however, Co.sub.2 laser, argon laser, YAG laser, excimer laser,
fiber laser, quartz laser and the like are included. The adhesive
layer 75 can be removed with the laser at a scan speed of 50 to
11000 m/sec, a wavelength of 10 to 100000 nm, and a frequency of 1
to 200 kHz.
[0060] In case of YAG laser, when treatment is executed under the
condition at a scan speed of 50 to 3000 m/sec, a wavelength of 1064
nm, and a frequency of 1 to 200 kHz, only the adhesive layer 75
applied on the surface of the slinger 7 can be removed. Further,
under the condition at a scan speed of 200 m/sec, a wavelength of
1064 nm, and a frequency of 5 kHz, the adhesive layer 75 can be
more preferably removed.
[0061] When any values mentioned above are not satisfied in the
laser treatment, the adhesive layer 75 cannot be completely
removed. When any values exceed the above mentioned conditions, the
slinger 7 is melt. According to several trials by the inventors of
the present invention, it is found that the adhesive layer 75 tends
to remain when the scan speed is low.
[0062] Under such laser treatment, accurate and effective treatment
can be executed at the slidably contacting surface 73 of the
slinger 7 of which treating face is alike a ring and the area is
small. Further, the degree of treatment can be easily controlled
depending on the characteristic of the material of the slinger 7
and the thickness of the adhesive layer 75 by the laser
treatment.
[0063] In case of YAG laser, when treatment is executed under the
condition at a scan speed of 50 to 2000 m/sec, a wavelength of 1064
nm, and a frequency of 20 to 200 kHz, surface roughening process
can be executed in addition to removal of the adhesive layer 75.
Further, under the condition at a scan speed of 500 m/sec, a
wavelength of 1064 nm, and a frequency of 20 kHz, the adhesive
layer 75 can be more preferably removed.
[0064] Accordingly, the adhesive layer 75 can be removed from the
slidably contacting surface 73 and surface roughening treatment of
the slidably contacting surface 73 can be executed by one process,
thereby facilitating the production procedure.
(Shot Peening Treatment)
[0065] The following conditions are employed for a shot peening
treatment for removing the adhesive layer 75.
[0066] According to a shot peening treatment, the adhesive layer 75
is removed or the slidably contacting surface 73 can be executed
with roughening treatment in addition to removal of the adhesive
layer 75 by shooting and hitting minute solid particles thereon. A
steel ball having a diameter of 20 to 200 .mu.m is used as the
minute solid particle and is shot to be hit on the slidably
contacting surface 73 at a shooting speed of 50 to 200 m/sec.
Minute solid particles made of metal, glass or ceramic may be
used.
[0067] When any values mentioned above are not satisfied in the
shot peening treatment, the adhesive layer 75 cannot be completely
removed. When any values exceed the above mentioned conditions, the
surface of the slinger 7 is too roughened and its strength is
adversely affected.
[0068] According to the shot peening treatment, the roughened
surface becomes an uneven surface without edges like a laser
treatment, so that the friction resistance of the slidably
contacting surface 73 can be effectively reduced. Further, under
the above-mentioned condition, the adhesive layer 75 can be removed
and the slidably contacting surface 73 can be executed with surface
roughening treatment by one process, thereby facilitating the
production procedure.
[0069] Referring to FIG. 3, one example of the production procedure
of the sealing device 6 with tone wheel according to the first
embodiment is explained. Here, the production procedure of the
slinger 7 with tone wheel 70 is specifically explained.
[0070] As shown in FIG. 3a, the ring-like slinger 7 obtained by
sheet metal processing of stainless steel (SUS430 and the like) is
formed. The fitting cylindrical portion 71 of the slinger 7 is
formed so as to be fitted into the peripheral body of the inner
ring (hub 3 and the inner ring member 33), and the brim portion 72
is formed so as to be radially extended at the end of the fitting
cylindrical portion 71, which is outside relative to the sealed
portion S.
[0071] For applying an adhesive agent on the whole surface of thus
formed slinger 7, the slinger 7 is dipped in the adhesive agent
prepared in a vessel. When the whole surface of the slinger 7 is
applied with the adhesive agent, it is taken out of the vessel.
FIG. 3a shows the slinger 7 on which whole surface the adhesive
layer 75 is formed.
[0072] The slinger 7 of which whole surface is formed with the
adhesive layer 75 is placed at a fixed position in a mold (not
shown) to mold the tone wheel 70. Then, unvulcanized rubber or
resin material is charged from an inlet to the mold and an annular
molded body is integrally formed with the slinger 7. When the mold
is heated to harden the annular molded body and the adhesive layer
is also heated and hardened, a plurality of S poles and N poles are
alternately provided along the circumferential direction to
magnetize the annular molded body. Then, the tone wheel 70 firmly
and integrally stuck to the slinger 7 can be taken out of the mold
(see FIG. 3b).
[0073] Thus obtained tone wheel 70 is shaped like a claw so as to
cover the end of the brim portion 72 of the slinger 7 as shown in
the figure, so that the adhesive agent can be spread on the whole
sticking surface of the tone wheel 70 even if the sticking surface
includes a small portion, thereby allowing the tone wheel 70 to
firmly adhere to the slinger 7.
[0074] The adhering method of the tone wheel 70 and the slinger 7
is not limited to the cure adhesion as mentioned above. The forming
method of the adhesive layer 75 is not limited to the example
mentioned above, and the adhesive agent may be applied on the whole
surface of the slinger 7 with a brush.
[0075] After the outer surface 74 of the slinger 7 is attached with
the tone wheel 70, the adhesive layer 75 formed on the slidably
contacting surface 73 of the slinger 7 with the seal lip (82) is
removed (see FIG. 3c). The removal method of the adhesive layer 75
is not specifically limited, however the adhesive layer 75 may be
scraped off by the above-mentioned laser treatment or it may be
wiped off with an adhesive removing liquid which is to be used
depending on the component of the adhesive agent forming the
adhesive layer 75.
[0076] As mentioned above, the adhesive layer 75 can be removed and
in addition the surface roughening treatment as shown in the
enlarged view of "Y" portion in FIG. 2 can be executed by a laser
treatment, thereby facilitating the treatment procedure and being
preferable.
[0077] Accordingly, the slinger 7 integrally stuck with the tone
wheel 70 can be produced, and the sealing device 6 with the tone
wheel 70 is constituted by combining thus produced slinger 7 and
the core material 80 fixed with the elastic sealing member 8 (see
FIG. 2).
[0078] The surface roughening treatment mentioned above is not
always necessary and the torque can be reduced comparing with the
slidably contacting surface 73 formed with the adhesive layer 75
only by removing the adhesive layer 75.
[0079] Other example different from the production procedure of
FIG. 3 is explained referring to FIG. 4. The common members to the
above-mentioned example is allotted with the same reference numbers
and their explanations are omitted here.
[0080] As shown in FIG. 4a, the ring-like slinger 7 obtained by
sheet metal processing of stainless steel (SUS430 and the like) is
formed. The slinger 7 has the fitting cylindrical portion 71 and
the brim portion 72 like FIG. 3.
[0081] For applying an adhesive agent on the whole surface of the
slinger 7, the slinger 7 is dipped in the adhesive agent prepared
in a vessel. When the whole surface of the slinger 7 is applied
with the adhesive agent, it is taken out of the vessel. FIG. 4a
shows the slinger 7 on which whole surface the adhesive layer 75 is
formed.
[0082] The surface of the slinger 7 formed with the adhesive layer
75 other than the slidably contacting surface 73 is covered with a
jig as shown with a dotted line in FIG. 4b. Then the adhesive layer
75 formed on the exposed slidably contacting surface 73 is removed.
The removal method is mentioned above.
[0083] After the removal treatment of the adhesive layer 75, the
slinger 7 is placed at a fixed position in a mold (not shown) to
mold the tone wheel 70. Then, the tone wheel 70 is formed and
magnetized as mentioned above.
[0084] Then, the tone wheel 70 firmly and integrally stuck to the
slinger 7 can be taken out of the mold (see FIG. 4c). Accordingly,
the sealing device 6 with the tone wheel 70 is obtained by
combining thus produced slinger 7 and the core material 80 fixed
with the elastic sealing member 8 (see FIG. 2).
[0085] Thus obtained tone wheel 70 is shaped like a claw so as to
cover the end of the brim portion 72 of the slinger 7 as shown in
the figure like the production method in FIG. 3, so that the
adhesive agent can be spread on the whole sticking surface of the
tone wheel 70 even if the sticking surface includes a small
portion, thereby allowing the tone wheel 70 to firmly adhere to the
slinger 7.
[0086] The removal method of the adhesive layer 75 mentioned above
is to cover the surface other than the slidably contacting surface
73 (the sticking surface of the tone wheel 70 in the above example)
with a jig to expose the slidably contacting surface 73, however
this invention is not limited to such a method. For example, the
surface other than the objective slidably contacting surface 73 may
be covered with a special masking member or when the surface other
than the slidably contacting surface 73 is partially exposed, only
the exposed surface may be covered with a masking member.
[0087] FIG. 5 shows a modified embodiment of the sealing device of
the first embodiment wherein a rotary side seal lip 11 is provided
for the slinger 7 as a fixing member.
[0088] The common members as the above-mentioned embodiment have
the same reference numbers and their explanations are omitted.
[0089] The rotary side seal lip 11 is made of a rubber material
selected from NBR, H-NBR, ACM, AEM, FKM like the sealing member 8.
The rotary side seal lip 11 comprises a tip portion 11a which
slidably contacts the cylindrical portion 80a of the core member
80, a crooked portion bent into the sealed portion S, and a base
portion 11c which is integrally fixed to the end of the brim
portion 72 of the slinger 7 so as to cover along its edge.
[0090] The adhesive layer 75 is once formed on the whole surface of
the slinger 7 and the adhesive agent can be spread on the whole
sticking surface of the rotary side seal lip 11 with small
attaching sticking area, so that the rotary side seal lip 11 can be
firmly adhered to the slinger 7 in the embodiment of FIG. 5. The
tip portion 11a of the rotary side seal lip 11 fixed to the slinger
7 elastically and slidably contacts with the core member 80, so
that the sealing ability of the bearing unit 1 can be kept by the
elastic slidable contact of both seal lips. Specifically, by
providing the rotary side seal lip 11, the centrifugal force is
exerted accompanied with rotation of the inner ring (3, 33) and
dust and dirt are effectively prevented from entering into the
bearing unit 1, thereby responding a severe sealing required
performance.
[0091] The adhesive layer 75 is removed from the slidably
contacting surface 73 to which the seal lip 82 of the sealing
member 8 slidably contacts by the above-mentioned method also in
the embodiment of FIG. 5, so that the friction resistance of the
seal lip 82 can be reduced, thereby achieving remarkable reduction
of the rotary torque.
[0092] The second embodiment of the present invention is explained
referring to FIG. 6 to FIG. 8.
[0093] The common members to the above-mentioned first embodiment
are allotted with the same reference numerals and their
explanations are omitted.
[0094] The second embodiment is different from the first embodiment
in that other member 9 is interposed on the upper surface of the
slidably contacting surface 73 of the slinger 7 with the seal lip
82 and a slidably contacting surface 93 is constituted. The other
member 9 provided at the slidably contacting surface 73 side of the
slinger 7 and they are integrally stuck via the adhesive layer 75.
The portion to which the sealing device 6 with the tone wheel 70 is
attached and structures of the slinger 7, the core member 80 and
the sealing member 8 are the same as those in the first
embodiment.
[0095] The production procedure of the sealing device 6 with the
tone wheel 70 according to the second embodiment is explained
referring to FIG. 7. Here, the production procedure of the slinger
7 with the tone wheel 70 is specifically explained.
[0096] The forming method of the slinger 7 and the method of
forming the adhesive layer on the whole surface of the slinger 7
and integrally sticking the tone wheel 70 are the same as those in
the first embodiment, so their explanations are omitted.
[0097] FIG. 7a shows that the adhesive layer 75 is formed on the
whole surface of the slinger 7. After the tone wheel 70 is
integrally stuck to a position which becomes the outer surface 74
of the tone wheel 70 under such condition, the other member 9 is
provided at the surface 76 of the slinger 7 to which the seal lip
(82) slidably contacts (see FIG. 7b). The other member 9 may be
provided after the tone wheel 70 is stuck or after the other member
9 is provided, the tone wheel 70 may be integrally stuck.
[0098] The other member 9 provided on the upper surface of the of
the slidably contacting surface 73 comprises a cylindrical portion
91 formed so as to be overlapped with the fitting cylindrical
portion 71 of the slinger 7 and a brim portion 92 formed so as to
be overlapped with the brim portion 72 of the slinger 7. The other
member 9 is formed by sheet metal processing of stainless steel
like SUS430 or engineering plastic, ceramics, glass, industrial
diamond, a resin material with low friction, elastomer and so on
like the slinger 7. Because the other member 9 is fitted to the
surface of the slinger 7 to which the seal lip (82) slidably
contacts via the adhesive layer 75, it is integrally fitted to the
slinger 7 firmly. Of course, the slinger 7 and the other member 9
may be integrally adhered with the adhesive layer 75.
[0099] The shape of the tone wheel 70 shown in the figure is the
same as that in the first embodiment.
[0100] Thus, the slinger 7 integrally stuck with the tone wheel 70
can be produced, and the sealing device 6 with the tone wheel 70 is
constituted by combining thus produced slinger 7 and the core
member 80 fixed with the elastic sealing member 8 (see FIG. 6).
[0101] Accordingly, the adhesive layer 75 is not formed on the
slidably contacting surface 93 with the seal lip 82 because the
other member 9 is interposed, so that the friction resistance of
the seal lip 82 can be reduced and reduction of the rotary torque
can be achieved.
[0102] Also in this case, the whole sticking surface of the tone
wheel 70 is filled with the adhesive agent applied on the whole
surface of the slinger 7, so that an adhesive agent spreads into
every end of the tone wheel 70 and the tone wheel 70 can be firmly
adhered to the slinger 7.
[0103] Further according to the second embodiment, when the
slidably contacting surface 93 of the other member 9 is treated to
be roughened, the friction resistance of the seal lip 82 can be
more reduced and remarkable reduction of the rotary torque can be
achieved. The treatment method of surface roughening may be the
same as that in the first embodiment, and it may be executed before
integrally fitting to the slinger 7 or it may be executed after
integral fitting.
[0104] FIG. 8 shows an modified embodiment of the sealing device of
the second embodiment. Here explained is a sample in which the
rotary side seal lip 11 is provided for the slinger 7 as the fixing
member.
[0105] The common members to the above-mentioned embodiment have
the same reference numbers and their explanations are omitted.
[0106] The rotary side seal lip 11 is the same as that in the
example in FIG. 5 and is formed so as to slidably contact the
cylindrical portion 80a of the core member 80 and is integrally
fixed to the end of the brim portion 72 of the slinger 7 so as to
cover along its edge.
[0107] In this case, the adhesive layer 75 is not formed on the
slidably contacting surface 93 of the seal lip 82 because the other
member 9 is interposed, so that the friction resistance of the seal
lip 82 can be reduced and reduction of the rotary torque can be
achieved. The whole surface of the slinger 7 is formed with the
adhesive layer 75 and the adhesive agent can be spread on the whole
sticking surface of the rotary side seal lip 11 with small sticking
area, thereby allowing the rotary side seal lip 11 to firmly adhere
to the slinger 7.
[0108] It goes without saying that the present invention is not
limitedly applied to the bearing unit 1 in the figure, however, it
can be applied to the bearing mechanism in which the inner ring is
fixed or the outer ring is fixed. The structure of the sealing
device 6, the shape of the tone wheel 70, the sealing member 8 and
the rotary side seal lip 11 are not limited to those shown in the
figure.
* * * * *