U.S. patent application number 11/384298 was filed with the patent office on 2006-11-02 for bonding method for elastic member and metal, and power transmission device.
This patent application is currently assigned to DENSO CORPORATION. Invention is credited to Toshihiro Konishi, Michiyasu Nosaka, Haruhisa Shibata, Yasuo Tabuchi, Yoshiki Tada.
Application Number | 20060245936 11/384298 |
Document ID | / |
Family ID | 36999127 |
Filed Date | 2006-11-02 |
United States Patent
Application |
20060245936 |
Kind Code |
A1 |
Shibata; Haruhisa ; et
al. |
November 2, 2006 |
Bonding method for elastic member and metal, and power transmission
device
Abstract
Vulcanizing-bonding is carried out using at least a phenolic
resin-based vulcanized adhesive F and a silicon compound-based
vulcanized adhesive C. Based on an idea of making a penetration of
water through a portion bonded with metal difficult, decreasing the
adhesion with metal is prevented by utilizing the phenolic
resin-based vulcanized adhesive F through which less water can
penetrate than the silicon compound-based vulcanized adhesive C,
and can increases a thickness of a membrane. Thereby, EPDM or AEM
vulcanizable with a peroxide can be strongly bonded to metal, by
forming a two-layered structure of the phenolic resin-based
vulcanized adhesive F and the silicon compound-based vulcanized
adhesive C. Further, a range of selecting a rubber material as an
elastic member to be utilized by bonding to metal can be
broadened.
Inventors: |
Shibata; Haruhisa;
(Okazaki-city, JP) ; Tabuchi; Yasuo;
(Toyoake-city, JP) ; Nosaka; Michiyasu;
(Anjo-city, JP) ; Konishi; Toshihiro; (Oobu-city,
JP) ; Tada; Yoshiki; (Okazaki-city, JP) |
Correspondence
Address: |
POSZ LAW GROUP, PLC
12040 SOUTH LAKES DRIVE
SUITE 101
RESTON
VA
20191
US
|
Assignee: |
DENSO CORPORATION
Kariya-city
JP
|
Family ID: |
36999127 |
Appl. No.: |
11/384298 |
Filed: |
March 21, 2006 |
Current U.S.
Class: |
417/223 |
Current CPC
Class: |
C08J 2323/16 20130101;
F16D 27/14 20130101; F16D 27/112 20130101; F16H 55/36 20130101;
F16D 3/58 20130101; C08J 5/128 20130101 |
Class at
Publication: |
417/223 |
International
Class: |
F04B 49/00 20060101
F04B049/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 23, 2005 |
JP |
2005-0084692 |
Claims
1. A method for bonding an elastic member made of an
ethylene-propylene-diene copolymer (EPDM) vulcanizable with a
peroxide or an elastic member made of an acryl-ethylene copolymer
(AEM) vulcanizable with a peroxide to metal, characterized by
utilizing at least a phenolic resin-based vulcanized adhesive (F)
and a silicon compound-based vulcanized adhesive (C) to vulcanize
and bond.
2. The method for bonding an elastic member to metal according to
claim 1, characterized by laminating the metal, the phenolic
resin-based vulcanized adhesive (F), the silicon compound-based
vulcanized adhesive (C), and the ethylene-propylene-diene copolymer
(EPDM) or the acryl-ethylene copolymer (AEM) in that order, and
bonding them.
3. The method for bonding an elastic member to metal according to
claim 1, characterized by that a thickness of each layer of the
phenolic resin-based vulcanized adhesive (F) and the silicon
compound-based vulcanized adhesive (C) is from 3 to 15 .mu.m.
4. The method for bonding an elastic member to metal according to
claim 1, characterized by a surface roughness Rz of the metal is
from 3 to 12.5.
5. A power transmission device for transmitting a rotational motive
power of a driving source to a rotating device (7) at a passive
side, comprising a pulley (1) which receives a rotational motive
power from a driving source to rotate, and a hub (2) which is
arranged coaxially with the pulley (1), and is connected to a
rotating shaft (3) of the rotating device (7) to rotate as one
piece with the rotating shaft (3), wherein the hub (2) has a
hub-side engaging portion (24) composed of an elastic member
connected to an inner-periphery face side or an outer-periphery
face side, or an inner- and outer-periphery face sides of an outer
periphery portion (23) engaged with a front-side end face of the
pulley (1), the pulley (1) has a pulley-side engaging portion (12)
formed on the front-side end face corresponding to the outer
periphery portion (23) of the hub (2), and a torque-transmitting
structure of the hub (2) and the pulley (1) is formed by allowing
the hub-side engaging portion (24) and the pulley-side engaging
portion (12) to engage, characterized by utilizing an elastic
member made of an ethylene-propylene-diene copolymer (EPDM)
vulcanizable with a peroxide or an elastic member made of an
acryl-ethylene copolymer (AEM) vulcanizable with a peroxide for the
hub-side engaging portion (24), and bonding the hub (2) made of
metal and the hub-side engaging portion (24) with a method for
bonding an elastic member to metal according to claim 1.
6. A power transmission device for transmitting a rotational motive
power of a driving source to a rotating device (7) at a passive
side, comprising a pulley (1) which receives a rotational motive
power from a driving source to rotate, and a hub (2) which is
arranged coaxially with the pulley (1), and is connected to a
rotating shaft (3) of the rotating device (7) to rotate as one
piece with the rotating shaft (3), wherein the hub (2) is composed
of an inner hub (21) connected to the rotating shaft (3), an outer
hub(23) engaged to a front-side end face of the pulley (1), a
torque-transmitting elastic member (22) connected to both of the
inner hub (21) and the outer hub(23) by intervening between the
both hubs (21, 23), and a hub-side engaging portion (24) formed at
the outer hub(23), the pulley (1) has a pulley-side engaging
portion (12) formed at a position corresponding to the outer
hub(23) of the front-side end face, and a torque-transmitting
structure of the hub (2) and the pulley (1) is formed by allowing
the hub-side engaging portion (24) and the pulley-side engaging
portion (12) to engage, characterized by utilizing an elastic
member made of an ethylene-propylene-diene copolymer (EPDM)
vulcanizable with a peroxide or an elastic member made of an
acryl-ethylene copolymer (AEM) vulcanizable with a peroxide for the
torque-transmitting elastic member (22), and bonding the both hubs
(21, 23) made of metal and the torque-transmitting elastic member
(22) with a method for bonding an elastic member to metal according
to claim 1.
7. A power transmission device for transmitting a rotational motive
power of a driving source to a rotating device (7) at a passive
side, comprising a pulley (1) which receives a rotational motive
power from a driving source to rotate, and a hub (2) which is
arranged coaxially with the pulley (1), and is connected to a
rotating shaft (3) of the rotating device (7) to rotate as one
piece with the rotating shaft (3), wherein the pulley (1) has an
electromagnetic coil (30) generating an electromagnetic force via
an electricity, the hub (2) is composed of an inner hub (60)
connected to the rotating shaft (3), an armature (50) receiving a
rotational motive power of the pulley (1) by being adsorbed to the
pulley (1) via an electromagnetic force generated by the
electromagnetic coil (30), and a spring-plate member (61) in a
shape of a circular plate which is connected to the inner hub (60),
and generates a spring force in a direction of estranging the
armature (50) from the pulley (1), and the armature (50) and the
spring-plate member (61) are directly connected via an elastic
member (63), characterized by utilizing an elastic member made of
an ethylene-propylene-diene copolymer (EPDM) vulcanizable with a
peroxide or an elastic member made of an acryl-ethylene copolymer
(AEM) vulcanizable with a peroxide for the elastic member (63), and
bonding the armature (50 and the spring-plate member (61)) made of
metal and the elastic member (63) with a method for bonding an
elastic member to metal according to claim 1.
Description
TECHNICAL FIELD
[0001] The present invention relates to a method for bonding an
elastic member made of an ethylene-propylene-diene copolymer (EPDM)
vulcanizable with a peroxide, or an elastic member made of an
acryl-ethylene copolymer (AEM) vulcanizable with a peroxide to a
metal, and a power transmission device formed using the method.
BACKGROUND ART
[0002] There is a power transmission device, such as a pulley
device and an electromagnetic clutch, which transmits a rotational
motive power of a driving source such as an engine to a rotating
device such as a compressor on a passive side. Such a power
transmission device is composed of a pulley which rotates by
receiving rotational motive power from a driving source and a hub,
which is arranged coaxially with this pulley, connected to a
rotating shaft of a rotating device to rotate as one piece with the
rotating shaft.
[0003] Japanese unexamined patent publication No. 2002-364667
describes one example of a power transmission device as follows. In
the power transmission device, a hub has a hub-side engaging
portion composed of an elastic member connected to an outer
periphery portion engaged with a front-side end face of a pulley,
while the pulley has a pulley-side engaging portion formed at a
position corresponding to the outer periphery portion of the
front-side end face. The power transmission device forms a
torque-transmitting structure with the hub and the pulley, by
allowing to the hub-side engaging portion and the pulley-side
engaging portion to engage.
[0004] In the past, a synthetic rubber such as a chlorinated butyl
rubber has been utilized for an elastic member of such a power
transmission device. FIG. 8 is a schematic drawing of a sectional
view showing a conventional method for bonding the chlorinated
butyl rubber and metal (a hub), wherein a metal, an adhesive (F)
mainly composed of phenol, an adhesive (H) mainly composed of a
halide, and a chlorinated butyl rubber are laminated in order, and
are bonded with a method such as a vulcanizing-bonding method.
SUMMARY OF INVENTIONS
[0005] When the chlorinated butyl rubber is utilized for the
elastic member of the power transmission device as described above,
bonding of the rubber and the metal bond is strong, however there
is a problem that the chlorinated butyl rubber has poor wear
characteristics. As elastic members with excellent wear
characteristics, an elastic member made of an
ethylene-propylene-diene copolymer (hereafter referred to as EPDM)
and an elastic member made of an acryl-ethylene copolymer
(hereafter referred to as AEM), both vulcanizable with a peroxide,
are known. However, EPDM and AEM vulcanizable with a peroxide
cannot bond to a conventionally-utilized adhesive (H) mainly
composed of a halide, and there is a problem that there has not
been any effective method of bonding with metal.
[0006] Inventors of the present invention found that an effective
bonding can be obtained, by applying a silicon compound--(e.g.
silane)based adhesive, which was proposed for a fluororubber, to
EPDM and AEM. Generally, the silane-based adhesive is supplied for
bonding as only the adhesive itself. However, when a saline-water
spraying test was carried out using an adhesive where only this
silane-based adhesive was utilized, a problem that adhesion of the
adhesive rapidly decreases for a relatively short period was found
(see a graph shown in FIG. 5).
[0007] The present invention was achieved by considering problems
of the above-mentioned prior art. A purpose of the present
invention is to provide a method for bonding strongly EPDM and AEM
vulcanizable with a peroxide to metal. Another purpose is to
provide a power transmission device of which wear characteristics
are improved by utilizing EPDM or AEM as an elastic member.
[0008] In order to achieve the above-mentioned purpose, the present
invention employs technical means described in the claims. In other
words, the first aspect of the present invention provides a method
for bonding an elastic member made of an ethylene-propylene-diene
copolymer (EPDM) vulcanizable with a peroxide or an elastic member
made of an acryl-ethylene copolymer (AEM) vulcanizable with a
peroxide to metal, characterized by utilizing at least a phenolic
resin-based vulcanized adhesive (F) and a silicon compound-based
vulcanized adhesive (C) to vulcanize and bond.
[0009] As the cause, where the adhesion in a case using only the
silicon compound-based vulcanized adhesive (C) decreases after
spraying saline-water, it was found that the silicon compound-based
vulcanized adhesive (C) can easily be penetrated with water due to
its structure, water can easily enter into a portion bonded with
metal due to difficulty of increasing a thickness of a membrane,
and an interface with the adhesive is hydrolyzed and becomes easily
released due to the water.
[0010] In a study for improving such a mechanism of decreasing the
adhesion, based on the idea of reducing a tendency for water to
penetrate into the portion bonded with metal, the inventors of the
present invention aimed to prevent the adhesion with a metal from
decreasing by employing the phenolic resin-based vulcanized
adhesive (F) which is less penetrated with water than the silicon
compound-based vulcanized adhesive (C), and of which the thickness
can become large.
[0011] According to the first aspect of the present invention, EPDM
or AEM vulcanizable with a peroxide can be strongly bonded with
metal, by utilizing a two-layered structure of the phenolic
resin-based vulcanized adhesive (F) and the silicon compound-based
vulcanized adhesive (C). Further, a range of selecting a rubber
material for an elastic member to be utilized by bonding to metal
can be broadened.
[0012] One embodiment of the first aspect of the present invention
provides a method for bonding an elastic member to metal,
characterized by laminating the metal, the phenolic resin-based
vulcanized adhesive (F), the silicon compound-based vulcanized
adhesive (C), and the ethylene-propylene-diene copolymer (EPDM) or
the acryl-ethylene copolymer (AEM) in order, and bonding them.
[0013] According to the embodiment of the first aspect of the
present invention, it is possible to reduce the tendency of being
penetrated with water into the portion bonded with metal, by
forming a layer of the phenolic resin-based vulcanized adhesive (F)
between the silicon compound-based vulcanized adhesive (C) and the
metal, and to strongly bond EPDM or AEM vulcanizable with a
peroxide to the metal.
[0014] Another embodiment of the first aspect of the present
invention provides a method for bonding an elastic member to metal
described in the above-mentioned embodiment, further characterized
by that a thickness of each layer of the phenolic resin-based
vulcanized adhesive (F) and the silicon compound-based vulcanized
adhesive (C) is from 3 to 15 .mu.m. Based on the embodiment of the
present invention, it is possible to obtain good adhesion.
[0015] Another embodiment of the first aspect of the present
invention provides a method for bonding an elastic member to metal
described in the above-mentioned embodiment, further characterized
by a surface roughness Rz of the metal is from 3 to 12.5. According
to the embodiment of the present invention, it is possible to
obtain good adhesion.
[0016] The second aspect of the present invention provides a power
transmission device for transmitting a rotational motive power of a
driving source to a rotating device (7) at a passive side,
comprising
[0017] a pulley (1) which receives a rotational motive power from a
driving source to rotate, and
[0018] a hub (2) which is arranged coaxially with the pulley (1),
and is connected to a rotating shaft (3) of the rotating device (7)
to rotate as one piece with the rotating shaft (3),
[0019] wherein the hub (2) has a hub-side engaging portion (24)
composed of an elastic member connected to an inner-periphery face
side or an outer-periphery face side, or an inner- and
outer-periphery face sides of an outer periphery portion (23)
engaged with a front-side end face of the pulley (1),
[0020] the pulley (1) has a pulley-side engaging portion (12)
formed on the front-side end face corresponding to the outer
periphery portion (23) of the hub (2), and
[0021] a torque-transmitting structure of the hub (2) and the
pulley (1) is formed by allowing the hub-side engaging portion (24)
and the pulley-side engaging portion (12) to engage,
[0022] characterized by
[0023] utilizing an elastic member made of an
ethylene-propylene-diene copolymer (EPDM) vulcanizable with a
peroxide or an elastic member made of an acryl-ethylene copolymer
(AEM) vulcanizable with a peroxide for the hub-side engaging
portion (24), and
[0024] bonding the hub (2) made of metal and the hub-side engaging
portion (24) with a method for bonding an elastic member to metal
according to the first aspect of the present invention.
[0025] According to the second aspect of the present invention, a
power transmission device with excellent wear characteristics can
be obtained.
[0026] The third aspect of the present invention provides a power
transmission device for transmitting a rotational motive power of a
driving source to a rotating device (7) at a passive side,
comprising
[0027] a pulley (1) which receives a rotational motive power from a
driving source to rotate, and
[0028] a hub (2) which is arranged coaxially with the pulley (1),
and is connected to a rotating shaft (3) of the rotating device (7)
to rotate as one piece with the rotating shaft (3),
[0029] wherein the hub (2) is composed of an inner hub (21)
connected to the rotating shaft (3),
[0030] an outer hub(23) engaged to a front-side end face of the
pulley (1),
[0031] a torque-transmitting elastic member (22) connected to both
of the inner hub (21) and the outer hub(23) by intervening between
the both hubs (21, 23), and
[0032] a hub-side engaging portion (24) formed at the outer
hub(23),
the pulley (1) has a pulley-side engaging portion (12) formed at a
position corresponding to the outer hub(23) of the front-side end
face, and
[0033] a torque-transmitting structure of the hub (2) and the
pulley (1) is formed by allowing the hub-side engaging portion (24)
and the pulley-side engaging portion (12) to engage, [0034]
characterized by [0035] utilizing an elastic member made of an
ethylene-propylene-diene copolymer (EPDM) vulcanizable with a
peroxide or an elastic member made of an acryl-ethylene copolymer
(AEM) vulcanizable with a peroxide for the torque-transmitting
elastic member (22), and [0036] bonding the both hubs (21, 23) made
of metal and the torque-transmitting elastic member (22) with a
method for bonding an elastic member to metal according to the
first aspect of the present invention.
[0037] The fourth aspect of the present invention provides a power
transmission device for transmitting a rotational motive power of a
driving source to a rotating device (7) at a passive side,
comprising [0038] a pulley (1) which receives a rotational motive
power from a driving source to rotate, and [0039] a hub (2) which
is arranged coaxially with the pulley (1), and is connected to a
rotating shaft (3) of the rotating device (7) to rotate as one
piece with the rotating shaft (3), [0040] wherein the pulley (1)
has an electromagnetic coil (30) generating an electromagnetic
force via an electricity, [0041] the hub (2) is composed of an
inner hub (60) connected to the rotating shaft (3), [0042] an
armature (50) receiving a rotational motive power of the pulley (1)
by being adsorbed to the pulley (1) via an electromagnetic force
generated by the electromagnetic coil (30), and [0043] a
spring-plate member (61) in a shape of a circular plate which is
connected to the inner hub (60), and generates a spring force in a
direction of estranging the armature (50) from the pulley (1), and
[0044] the armature (50) and the spring-plate member (61) are
directly connected via an elastic member (63), [0045] characterized
by [0046] utilizing an elastic member made of an
ethylene-propylene-diene copolymer (EPDM) vulcanizable with a
peroxide or an elastic member made of an acryl-ethylene copolymer
(AEM) vulcanizable with a peroxide for the elastic member (63), and
[0047] bonding the armature (50 and the spring-plate member (61))
made of metal and the elastic member (63) with a method for bonding
an elastic member to metal according to the first aspect of the
present invention.
[0048] According to the third and fourth aspects of the present
invention, it is possible to obtain a power transmission device
with excellent durability. By the way, a number in parentheses
attached to each above-described means is one example demonstrating
a corresponding relation with concrete means described in
embodiments explained hereafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0049] FIG. 1 shows a drawing of a front view to illustrate a power
transmission device in the first Embodiment of the present
invention.
[0050] FIG. 2 shows a longitudinal sectional drawing to illustrate
the power transmission device of FIG. 1.
[0051] FIG. 3 shows a drawing of a perspective view to illustrate a
hub 2 of the power transmission device shown in FIGS. 1 and 2.
[0052] FIG. 4 shows a schematic sectional drawing to illustrate a
method of bonding an elastic member and metal in one Embodiment of
the present invention.
[0053] FIG. 5 shows a graph to demonstrate a rate of change of
adhesion against a period of saline-water spraying.
[0054] FIG. 6 shows a longitudinal sectional drawing to illustrate
an electromagnetic clutch 100 in the second Embodiment of the
present invention.
[0055] FIG. 7 shows a drawing of a front view to illustrate a
spring-plate member 61 shown in FIG. 6, wherein a bonded area is
shown by hatching.
[0056] FIG. 8 shows a schematic sectional drawing to illustrate a
conventional method of bonding an elastic member and metal.
DETAILED DESCRIPTION
First Embodiment
[0057] A power transmission device which is an Embodiment according
to the present invention is explained in detail as follows, based
on the Figures attached hereto. FIG. 1 is a drawing of a front view
to illustrate a power transmission device in the first Embodiment
of the present invention. FIG. 2 is a longitudinal sectional
drawing to illustrate the power transmission device of FIG. 1. FIG.
3 is a drawing of a perspective view to illustrate a hub 2 of the
power transmission device shown in FIGS. 1 and 2.
[0058] The power transmission device of the present invention is
preferably incorporated into a rotating device 7 such as a
compressor of an air-conditioner for vehicles, which rotates by
receiving a rotational motive power from a driving source such as
an engine or a motor. The power transmission device transmits the
rotational motive power (a rotational torque) between a pulley 1 as
a driving-side rotating member obtaining a driving from a driving
source, and a hub 2 as a following-side rotating member fixed to a
shaft (a rotating shaft) 3 of the compressor 7. These pulley 1 and
hub 2 are installed on the same shaft.
[0059] The pulley 1 is mounted rotatably in a cylindrical portion
4a installed at one side of a housing 4 of the compressor 7 via a
bearing 5 as a bearing device. The pulley 1 is preferably formed
with a thermoplastic synthetic resin, but may be formed with a
metal material such as iron. When the pulley 1 is made of a resin,
the pulley 1 and the bearing 5 are usually formed as one piece by
an insert-molding method.
[0060] A belt, not shown in the Figure, is wound on an outer
periphery face of the pulley 1, and rotates via a motive power from
an outside member such as an engine or a motor. The bearing 5 fits
into the cylindrical portion 4a, and is prevented from moving in a
direction of the shaft by a snap-ring 5a as a fixing ring fitted
into a groove formed at the outer periphery face of the cylindrical
portion 4a. The housing 4 and the shaft 3 are sealed by a
shaft-sealing member 6a as a shaft-sealing device, and prevent a
refrigeration medium or oil from leaking.
[0061] A tip end portion 31 of the shaft 3 in the compressor 7
protrudes from the housing 4, and a screw portion is formed at the
outer periphery face of the tip end portion 31. Further, a
cylindrical hub 2 is fixed on the tip end portion 31 via
screw-engaging. For fixing the hub 2 to the shaft 3, other fixing
methods such as spline-engaging or fixing with a bolt can be
utilized. The item "8" is a washer.
[0062] The hub 2 is configured with an inner hub 21, a damper
rubber 22 as the elastic member for torque-transmitting, and an
outer hub 23, as well as a hub-side engaging portion 24. The inner
hub 21 is composed of a cylindrical portion 21a screw-engaged to
the tip end portion 31 of the shaft 3, a cylindrical flange portion
21c which protrudes toward a front side (a left side in FIG. 2) and
of which an outer periphery face is connected to the damper rubber
22, and a discal intermediate portion 21b connecting the
cylindrical portion 21a and the flange portion 21c.
[0063] At an inner-periphery face of the cylindrical portion 21a, a
screw portion is formed. The inner hub 21 is formed with a metal
material such as iron. The outer hub 23 has a cylindrical shape,
and is formed with a metal material such as iron in the same manner
as the inner hub 21. The annular damper rubber 22, which is the
elastic member for torque-transmitting, is formed with the elastic
member of a rubber material such as EPDM, AEM and chlorinated
butyl, and is maintained by intervening between the inner hub 21
and the outer hub 23. Further, it is connected to the outer
periphery face of the flange portion 21c of the inner hub 21 and
the inner periphery face of the outer hub 23 via bonding means.
[0064] The damper rubber 22 functions not only as the elastic
member for torque-transmitting, but also as a torque damper. A
first hub-side engaging portion 24a is installed at an inner
periphery face 23a of a rear side of the outer hub 23 (a right side
in FIG. 2, an upper side in FIG. 3), and a second hub-side engaging
portion 24b is installed at an outer periphery face 23b, over the
approximately whole periphery of the outer hub 23.
[0065] The first and second hub-side engaging portions 24a and 24b
are formed from the elastic member of the rubber material such as
EPDM and AEM, and their outer shapes are in a state of unevenness
such as an involute-spline and a trochoid. These first and second
hub-side engaging portions 24a and 24b are respectively connected
to each periphery face of the outer hub 23 by bonding. The bonding
method of the damper rubber 22 and the both hubs 21, 23, and the
bonding method of the hub-side engaging portion 24 and the outer
hub 23 are described in detail later, since they are important to
the present invention.
[0066] The hub-side engaging portion 24 may be installed either at
the inner periphery face 23a or at the outer periphery face 23b of
the outer hub 23. Alternatively, as shown in FIG. 2, the first and
second hub-side engaging portions 24a and 24b and the damper rubber
22 may be united in one piece so that the first and second hub-side
engaging portions 24a and 24b wrap a rear-side portion of the outer
hub 23. Further, a hub 2, which has no damper rubber 22, and
comprises a torque-limiter portion which is broken on a priority
basis when too large a torque occurrs, may be utilized.
[0067] On the other hand, an annular concave portion 11 to receive
the hub-side engaging portion 24 at a front-side face also may be
formed at the pulley 1. At an inner-side face 11a and an outer-side
face 11b of the annular concave portion 11, a first pulley-side
engaging portion 12a and a second pulley-side engaging portion 12b
with outer shapes in an uneven shape such as an involute-spline and
a trochoid are formed.
[0068] These first and second pulley-side engaging portions 12a and
12b also may be formed with the elastic member of a rubber material
such as EPDM and AEM, and may bond to the inner face 11a or the
outer face 11b of the annular concave portion 11. The pulley-side
engaging portion 12 may be formed either at the inner face 11a or
at the outer face 11b of the annular concave portion 11.
[0069] In this manner, the first hub-side engaging portions 24a and
the first pulley-side engaging portion 12a are engaged together by
fitting the hub-side engaging portion 24 into the annular concave
portion 11 of the pulley 1, and the hub 2 and the pulley 1 are
connected together by allowing the second hub-side engaging portion
24b and the second pulley-side engaging portion 12b to engage
together.
[0070] In the above explanation, the peripheries of the hub-side
engaging portion 24 and the outer hub 23 are formed in a shape of a
continuous circular ring. However, as shown in FIG. 1 or the
drawing of a perspective view of the hub 2 in FIG. 2, for the
hub-side engaging portion 24 and the rear-side portion of the outer
hub 23 may be arranged so that plural slits 25 are formed at
regular intervals as appropriate in a peripheral direction.
[0071] By forming the hub-side engaging portion 24 and the rear
side portion of the outer hub 23 in a shape of plural divided
structures in this manner, a cheap, compact and lightweight power
transmission device, with no problem of interference between the
pulley 1 and the hub 2, may be obtained, by allowing a rib 11c to
correspond to the slit 25, at also a pulley structure where the rib
11c as a reinforcing portion is formed in a radial direction on a
bottom face of the concave portion 11 of the pulley 1 (see FIG. 1),
in the pulley 1 composed of a material such as, for example, a
resin of which the strength is respectively less than the metal of
the pulley 1.
[0072] The characteristics and an effect of this Embodiment will be
described. FIG. 4 is a schematic sectional drawing to illustrate a
method of bonding an elastic member and metal in one Embodiment of
the present invention. In the method for bonding EPDM (an elastic
member of ethylene-propylene-diene copolymer vulcanizable with a
peroxide) or AEM (an elastic member of acryl-ethylene copolymer
vulcanizable with a peroxide) to metal, vulcanizing-bonding is
carried out by utilizing at least the phenolic resin-based
vulcanized adhesive F and the silicon compound-based vulcanized
adhesive C.
[0073] Concrete examples of the phenolic resin-based vulcanized
adhesive F include, for example, CHEMLOCK 205 and CHEMLOCK 200
commercially available from Road Co. and the like. Concrete
examples of the silicon compound-based vulcanized adhesive C
include, for example, CHEMLOCK 608 and AP133 commercially available
from Road Co. and the like. FIG. 5 is a graph to demonstrate a rate
of change of adhesion against a period of saline-water
spraying.
[0074] Based on this, as recognized from the graph, it is possible
to strongly bond EDDM or AEM vulcanizable with a peroxide to metal,
by forming a two-layered structure of the phenolic resin-based
vulcanized adhesive F and the silicon compound-based vulcanized
adhesive C. Further, a range of selecting a rubber material as an
elastic member to be utilized by bonding to metal can be
broadened.
[0075] The metal, a phenolic resin-based vulcanized adhesive F, a
silicon compound-based vulcanized adhesive C, and EPDM or AEM are
laminated in order, and are bonded. Thereby, it can be made
difficult for water to penetrate into a portion bonded with metal,
and it is possible to strongly bond EDDM or AEM vulcanizable with a
peroxide to metal, by forming a layer of the phenolic resin-based
vulcanized adhesive F between the silicon compound-based vulcanized
adhesive C and the metal.
[0076] The thicknesses of layers of the phenolic resin-based
vulcanized adhesive F and the silicon compound-based vulcanized
adhesive C are respectively in a range from 3 to 15 .mu.m. The
surface roughness Rz of the metal is from 3 to 12.5. Based on these
characteristics, a good adhesion can be obtained in the present
invention.
[0077] The elastic member of EPDM or AEM are used at the hub-side
engaging portion 24, and the hub 2 and the hub-side engaging
portion 24 are bonded by utilizing the above-mentioned bonding
method of the elastic member and the metal. Thereby, it is possible
to obtain a power transmission device with excellent wear
characteristics. Further, EPDM or AEM also are used for the damper
rubber 22, and both hubs 21 and 23 made of metal and the damper
rubber 22 are bonded by utilizing the above-mentioned bonding
method of the elastic member and metal. Thereby, it is possible to
make a power transmission device with excellent wear
characteristics.
[0078] In the power transmission device where EPDM or AEM was
utilized for the hub-side engaging portion 24, when a resonance of
an auxiliary device and a resonance of a rubber are close, it is
preferred to use the chlorinated butyl for the damper rubber 22.
When the resonance of an auxiliary device and the resonance of a
rubber are different, it is preferred to use AEM for the damper
rubber 22. When the resonance of an auxiliary device and the
resonance of a rubber are low, it is preferred to use EPDM for the
damper rubber 22.
Second Embodiment
[0079] FIG. 6 is a longitudinal sectional drawing to illustrate an
electromagnetic clutch 100 in the second Embodiment of the present
invention. FIG. 7 is a drawing of a front view of the spring-plate
member 61 shown in FIG. 6, wherein a bonded area is shown with
hatching. This Embodiment shows an Example where the present
invention was applied to an electromagnetic clutch 100 to be
mounted into a compressor 7 of a refrigerating cycle for an
air-conditioner of a vehicle.
[0080] The electromagnetic clutch 100 comprises an electromagnetic
coil installed in a stator 20, a rotor 40 as a driving-side
rotating member to be rotatably driven by an engine for vehicles
(not shown in the Figure), an armature 50 to be adsorbed to the
rotor 40 via an electromagnetic force generated by the
electromagnetic coil 30, and a hub 6 as a following-side rotating
member which is connected to this armature 50 and rotates with the
armature 50 as one piece. This hub 6 is connected to the shaft 3 of
the compressor 7, and transmits the rotational motive power to the
compressor 7.
[0081] The stator 20 is formed with a magnetic material in a
sectional shape of the mark "" and the electromagnetic coil 30 is
installed in this stator 20. The electromagnetic coil 30 is
electrically insulated and fixed by molding in the stator by an
insulating resin member such as epoxy. The stator 20 is fixed in
the housing 4 of the compressor 7 via a supporting member 9 in a
shape of a ring.
[0082] The rotor 40 has a pulley 41a where a multi-stage typed
V-belt, not shown in the Figure, is looped over its outer periphery
portion, and rotates by a rotational motive power transmitted from
an engine via the V-belt. The rotor 40 is formed with a magnetic
material such as iron, in a sectional shape of the mark ""
installing the stator 20 via a small gap with the stator 20. The
rotor 40 comprises a bearing 5 at its inner periphery, and is
supported ratatably on the outer periphery face of a cylindrical
boss portion 4a of a compressor-housing 4 via this bearing 5.
[0083] The armature 50 is arranged opposite to a frictional surface
of the rotor 40 at a distance of desired small gap (e.g. about 0.5
mm), and is formed with a magnetic material such as iron in a ring
shape. The armature 50 of this Example forms a groove portion for
magnetically dividing an inner side ring portion and an outer side
ring portion, not shown in the Figure. The inner side ring portion
and the outer side ring portion are connected as one piece via a
bridge portion (a connecting portion) between the groove portions,
by dividing this groove portion into plural pieces in a
circumferential direction.
[0084] Then, the hub 6 is explained in detail. The hub 6 has an
inner hub 60 cylindrically formed with an iron-based metal wherein
a spline-engaging portion 60a is formed at an inner-periphery face
of the cylindrical portion of the inner hub 60, and is engaged to
the shaft 3 in one piece in a rotational direction at this
spline-engaging portion 60a. Installing-flange portions 60b
extending outside in a radial direction from one end portion of a
cylindrical portion of the inner hub 60 in a direction of the shaft
(the left end portion in FIG. 6) are formed in one piece at three
positions in a circumferential direction.
[0085] A following-side connecting portion 61a at the
inner-periphery portion of the spring-plate member 61 (FIG. 7) is
connected to these three installing-flange portions 60b via three
rivets 62. This spring-plate member 61 is configured with a spring
material made of an iron-based metal, and its whole shape is formed
in a shape of a circular plate as shown in FIG. 7.
[0086] A ring portion 60c, which protrudes in a ringed shape toward
inside in a radial direction from one end portion of a cylindrical
portion of the inner hub 60 in a direction of the shaft (the left
end portion in FIG. 6), is formed. This ring portion 60c is tightly
fixed to a tip end portion of the shaft 3 with a bolt 10. Thereby,
the hub 6 can be connected to the shaft 3 in one piece.
[0087] In the spring-plate member 61, as shown in FIG. 7,
plate-spring portions 61b extending in a radial direction are
formed at three positions between the following-side connecting
portion 61a of the inner-periphery portion. More concretely, a
connecting portion via the rivet 62, and a outer-periphery ring
portion 61f. Therefore, the longitudinal direction of the
plate-spring portion 61b is arranged to point in the radial
direction.
[0088] In order to form these plate-spring portions 61b, notched
grooves 61c, which compartment both sides in the circumferential
direction of the plate-spring portions 61b, are formed. Herein, the
notched groove 61c is in a shape of a curvature, and has groove
portions 61d, which are located at one side in a circumferential
direction of the adjoining plate-spring portions 61b, and an
intermediate groove portion 61e which connects these groove
portions 61d together. The curvature is formed so that the
intermediate groove portion 61e can position at the most inner
periphery side.
[0089] Tip end portions of the outer periphery side of the
above-mentioned plate-spring portions 61b located at three
positions are connected to the outer-periphery ring portion 61f in
one piece. Therefore, the spring-plate member 61 is formed in one
piece so that portions from the following-side connecting portion
61a of the inner-periphery portion to the outer-periphery ring
portion 61f can form one circular plate.
[0090] By the way, in this Embodiment, the curved shape of the
notched groove 61c is formed so that the intermediate groove
portion 61e of the notched groove 61c can be positioned further
inside than the inner-periphery face of the armature 50. Thereby, a
broad portion 61g which expands an area of the outer-periphery ring
portion 61f can be formed at the mutual intermediate portion of the
three plate-spring portions 61b. Further, the most inner periphery
portion of the broad portion 61g can be extended to more inner side
than the inner periphery face of the armature 50.
[0091] Then, the spring-plate member 61 and the armature 50 have
approximately the same outer diameter, and the elastic member 63
directly connecting the spring-plate member 61 and the armature 50
is installed between them. The elastic member 63 is formed from a
rubber-based elastic material, and as shown in FIG. 6, has a shape
of a ringed plate corresponding to the ringed shape of the armature
50. The elastic member 63 is bonded (fixed) in one piece to both of
the spring-plate member 61 and the armature 50 through a method of
vulcanizing-bonding (baking-bonding) in a desired molding tool.
[0092] More concretely, for the armature 50, the elastic member 63
is entirely bonded to the inner ring and the outer ring. However,
for the spring-plate member 61, the elastic member 63 is baked and
bonded only to portions closer to the outer periphery than the
notched groove 61c, in other words, portions of the outer-periphery
ring portion 61f and the broad portion 61g as shown with small dots
in FIG. 7.
[0093] Therefore, for the spring-plate member 61, even at a portion
positioned at more outer periphery side than the inner-periphery
face of the inner ring of the armature 50, the elastic member 63 is
not baked and bonded at the following-side connecting portion 61a
and the plate-spring portion 61b. This aims to prevent that elastic
deformation of the plate-spring portion 61b is inhibited by the
bonding of the elastic member 63.
[0094] In the step of baking and bonding, it can be easily
prevented to bond the elastic member 63 to the following-side
connecting portion 61a and the plate-spring portion 61b, by
employing a method for masking a coating of an adhesive applied to
the following-side connecting portion 61a and the plate-spring
portion 61b. For a rubber material utilized for the elastic member
63, a material which demonstrates excellent properties for
torque-transmitting and torque-change absorbing (vibration-damping)
against a wide variation of the ambient temperature for vehicles
(from -30.degree. C. to 120.degree. C.), is preferred.
[0095] Concretely, an elastic member made of an
ethylene-propylene-diene copolymer (EPDM) vulcanizable with a
peroxide or an elastic member made of an acryl-ethylene copolymer
(AEM) vulcanizable with a peroxide is utilized. For bonding the
elastic member, it is carried out to vulcanize and bond it as a
two-layered structure of the phenolic resin-based vulcanized
adhesive and the silicon compound-based vulcanized adhesive
(wherein the phenolic resin-based vulcanized adhesive is used at a
metal side).
[0096] Three holes 61h of the spring-plate member 61 are used in
order to insert a pin (not shown in the Figure), press it to the
armature 50, and keep the armature 50 at a desired position in the
molding tool, when the vulcanizing-bonding step is performed. In
the same manner, three holes 51 of the armature 50 are used to
insert a pin (not shown in the Figure), to press it to the
spring-plate member 61, and keep the spring-plate member 61 at a
desired position in the molding tool, when the vulcanizing-bonding
step is performed.
[0097] In this Embodiment, as thin-film covering portions 63a and
63b, which respectively cover the inner periphery face and the
outer periphery face of the armature 50, are formed as one piece
with the elastic member 63, it is possible to allow these thin-film
covering portions 63a and 63b to hold also the same
surface-protective action as a surface-treated layer. Therefore,
the surface-treating step for the armature 50 may become
unnecessary.
[0098] Next, an operation of this Embodiment with the
above-mentioned constitution is explained. At the time of stopping
electricity of the electromagnetic coil 30 (during turning the
clutch "off"), the armature 50 is maintained at a position with a
desired distance from a frictional surface of the rotor 40 via a
spring force of the plate-spring portion 61b of the spring-plate
member 61. Thereby, a rotational motive power from an engine of a
vehicle (not shown in the Figure) is transmitted only to the rotor
40 via a V-belt, but not transmitted to the armature 50 and the hub
6. Therefore, only the rotor 40 spins on the bearing 5, and the
compressor 7 is stopped.
[0099] On the other hand, when electricity is passed through the
electromagnetic coil 30, the armature 50 is sucked to the rotor 40
against the spring force of the plate-spring portion 61b of the
spring-plate member 61, via an electromagnetic force generated by
the electromagnetic coil 30. Further, the armature 50 is adsorbed
to the rotor 40. Then, a rotation of the rotor 40 is transmitted to
the shaft 3 of the compressor 7 through the armature 50, the
elastic member 63, the spring-plate member 61 and the inner hub 60,
and the compressor 7 is operated. When the electricity to the
electromagnetic coil 30 is shut off, the armature 50 returns to the
original estranging position via the spring force of the
plate-spring portion 61b of the spring-plate member 61, by
extinction of the electromagnetic force, and the compressor 7
returns to the stopped state.
[0100] By the way, bonding is carried out by allowing the elastic
member 63 to intervene between the armature 50 and the
outer-periphery ring portion 61f of the spring-plate member 61.
Therefore, in a step of adsorbing the armature 50 to the rotor 40
at the above-mentioned period of turning the clutch "On", a shock
and a vibration caused by adsorbing the armature to the frictional
surface of the rotor 40 can be reduced by a vibration-damping
action of the elastic member 63. In the same manner, a
torsion-resonance related to a driving-torque change of the
compressor 7 also can be relaxed by a vibration-damping action of
the elastic member 63. By these vibration-damping actions of the
elastic member 63, operating noises of the electromagnetic clutch
100 and the compressor 7 can be effectively reduced.
[0101] Further, a returning movement of the armature 50 in the
direction of the shaft during turning the clutch "Off" can be
carried out by the spring force of the plate-spring portion 61b of
the spring-plate member 61. Therefore, it is not necessary to allow
the elastic member 63 to hold also a spring action for the
returning movement of the armature 50 in the direction of the
shaft. Thereby, the elastic member 63 can be formed in the shape of
a thin plate along the radial direction of the armature 50 and the
outer-periphery ring portion 61f of the spring-plate member 61.
Further, a dimension of the elastic member 63 in the direction of
the shaft (a thickness of the plate) can be, for example, about 2
mm, and can be significantly decreased in comparison with a
dimension of a conventional cylindrical elastic member in the
direction of the shaft (generally, about 10 mm).
[0102] When a locking phenomenon of the compressor 7 happens for
any reason, the hub 6 and the armature 50 connected to the shaft 3
of the compressor 7 becomes unable to rotate, and thereby the rotor
40 rotates with sliding against the armature 50. As a result, the
frictional surface between the rotor 40 and the armature 50 is
heated, and a temperature of the elastic member 63 is elevated.
[0103] When the temperature is elevated to a meltdown temperature
which is determined by a material of the elastic member 63, the
elastic member 63 melts, and a state of connecting the armature 50
and the spring-plate member 61 is stopped. Therefore, after that,
the armature 50 remains to be adsorbed to the rotor 40, the rotor
40 rotates as one piece with the armature 50, and the torque
transmission between the armature 50 and the spring-plate member 61
is shut off. Therefore, a state of overloading due to the locking
phenomenon of the compressor 7 is cancelled. Thereby, an occurrence
of a problem such as cutting a belt and an abnormal elevation of
the temperature due to continuation of this overloading state for a
long period can be reduced.
[0104] Plural plate-spring portions 61b are formed between the
following-side connecting portion 61a of the inner periphery
portion and the outer-periphery ring portion 61f of the
spring-plate member 61 so that they can extend in the radial
direction. Thereby, the broadened-width portion 61g, which expands
the area of the outer-periphery ring portion 61f, can be formed at
the mutual intermediate portion of the plural plate-spring portions
61b.
[0105] Thereby, it is possible to enlarge a bonded area between the
spring-plate member 61 and the elastic member 63, to increase a
bonding strength between both members 61 and 63, and to improve
torsional durability of the clutch. The torsional durability can be
evaluated using the number of applications of a maximum torque of
the compressor, before when applying and releasing of the maximum
torque of the compressor are repeated between the armature 50 and
the hub 6 (the spring-plate member 61) at desired intervals, the
elastic member 63 is broken, and the torque transmission becomes
impossible.
[0106] In the above-mentioned Embodiment, a configuration of
connecting, in one piece, an inside ring portion 5 and an outside
ring portion of the armature 50 with a bridge portion (a connecting
portion) between plural arc-shaped grooves for electromagnetically
shutting off is made, and the whole armature 50 is formed as an
one-piece component. However, another configuration may be
utilized, where the inside ring portion and the outside ring
portion of the armature 50 are formed separately, a groove for
electromagnetically shutting off is arranged between the inside
ring portion and the outside ring portion, and the inside ring
portion and the outside ring portion are bonded in one piece to the
spring-plate member 61 through the elastic member 63.
[0107] Then, characteristics and an effect of this Embodiment are
described. The elastic member made of the ethylene-propylene-diene
copolymer (EPDM) vulcanizable with a peroxide or the elastic member
made of the acryl-ethylene copolymer (AEM) vulcanizable is utilized
for the elastic member 63, and the armature 50 and the spring-plate
member 61 made of metal, and the elastic member 63 are bonded using
the same bonding method of the elastic member and the metal as in
the above-mentioned first Embodiment. Thereby, the power
transmission device with excellent durability can be obtained.
[0108] The elastic member made of the ethylene-propylene-diene
copolymer (EPDM) vulcanizable with a peroxide and the elastic
member made of the acryl-ethylene copolymer (AEM) vulcanizable with
a peroxide in this Embodiment are respectively the elastic member
of an ethylene-propylene-diene copolymer (EPDM) and the elastic
member of the acryl-ethylene copolymer (AEM) subjected to
non-sulfur crosslinking with an organic peroxide (e.g. PERHEXA 25B
from NOF Corporation). In the specification of the present
application, "vulcanizable with a peroxide" and "crosslinking with
a peroxide" are used as terms of the same meaning.
Other Embodiments
[0109] In the above-mentioned Embodiments, the method for bonding
the elastic members and the metal in the present invention is
applied to the power transmission device. However, the present
invention is not limited to the Embodiments, and may also be
applied to bonding a metal member of a vibration-insulating device
and a rubber vibration insulator. Particularly, it is preferred for
a portion to be subjected to a high temperature. Further, a
treatment with a phosphite may be utilized as a treatment of a
surface of metal. The silane-based adhesive was utilized as the
silicon compound-based adhesive in the above-mentioned Embodiments.
However, the present invention is not limited to the Embodiments,
and any silicon-based compound may be utilized.
* * * * *