Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
BacJsqround oi~ tlle Invention
~ e ~resent invention re.lates to cylindrical
polylllel~ conlponent usirlg a novel reinforcement memb~r, and
whicll nlay be use~ul as a hose, a tire belt, or as an
interlllediate product ln ~he making of flexible drive belts,
9UCII as tlming belts. The invention also provides a method
of manufacturing sùcll components. The present application
Ls related to the subject matter of U.S. Patent No.
4,7()1.,1.54, fi.led in the name of -the present inventor and
assiglled to the assignee of the present invention.
Timing belts are flexible drive belts, similar to
pulley-t:ype belts, wllich have teeth on one ox more sides of
the belt whlch permitY the ~elt to perform much as gears
per.Lorlll ln trallsmlttlng preclse precision motion. ~iming
be:l.l:s, a.Lso Jcnown as synchronous belts, generally do not
transmlt the amount of power that a gear wlll transmi-t, but
offer light weight and alignment flexibility with the
advantage of non-slip precision motion transmission. In
sucll precisio~ motion transmission, the motion is
transmitted by the pulley teeth meshing with the belt teeth
and during the meshing operation of the engagement and
disengagement of the teeth, relative movements take place
between the pulley teeth and the belt teeth. Accordingly,
~everal prlor art structures and compositions have been
suggested for manufacturing belt structures which provlde a
high degree of fl~xibility while maintaining the necessary
wear anu liEe characteristics of the belt.
Belts for transmitting motion have been known for
mal~y yea.rs, as evidenced by U.S. patents 1,928,869,
30 1,611,829, 3,464,875 and 4,266,937 which describe processes
i.n wh.i.ch ~he cogs or teeth are perormed in some manner and
p].acecl boul: a drum and tllen the remaln.illg portion oE the
l-e.ll: coln,~onent:s or l~ell; sleeve ls wra~ecl aro!lrlcl l.he leetll
l.o I~Or~ he COmpJ.~ 'e('l IlllCl.lrF!CI be.l.t s.lr?eve. Mo.~e recel~t.ly
35 lJ. S ~ pat:F3nt ~ r 4~ lescr.i.~es a be.lt corlst.ructiol~ and tlle
mt-.~tllod of ~n~nufacture of tlle same.
Conventional timing belt constructlons for industrial
use, which include V-belts and drive belts con.structions,
are generally comprised of a polymeric matrix material,
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such as, rubber or polyurethane, and the like, reinforced
with a higher strength material, primarily glass, fabric
or an arumid, and with an even higher Young's modulus
filament, primarily metal, so as to resist stretching and
maintain precise belt-tooth spacing under operating load
conditions. Moreover, such timing belts, containing glass
or fabric reinforcements, generally do not possess
sufficient Young's modulus coefficients to withstand
stretching or elongation of the belt during operating
loads. Thus, the preferred reinforcement is generally
a metal, such as steel.
Although timing belts comprised of rubber reinforced
with metal filaments such as steel cables and the like
have bsen suggested, such belt structures present problems
relating to corrosion of the metal within the bPlt,
slipping and fatigue of the metal during operating load,
adhesion problems with respect to th2 metal to the rubber
reinforced belt construction and the difficulty of
producing a belt construction possessing the necessary
fle~ibility and stretch required in order to ef~ectively
u'cilize steel as a reinforcing member of the belt. The
flexibility of the belt is necessary to prevent, during
the opera'ting load conditions of the belt motlon
transmitted from the pulley teeth meshing with the belt
teeth, the engagement and disengagement of the pulley ~eeth
and the belt teeth with respect to each other, which action
results in substantial teeth wear in that portion of the
belt construction.
Importantly, also, and perhap~ the most important 30 di~icultly associated with the use o~ steel as the
reinorcem~nt ten~ile member within a be}t construction,
relate3 to the dlfficult~es associated wlth the use of
steel in the method of manufacturing for timing belts.
In general, timing or drive belts are manufactured by
applying an inner rubber rein~orced layer from a continuous
sheet around a mandrel drum having an outer surface
longitudinally grooved, which grooves provide the internal
~ teeth molded structure in the timing belt construction.
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Thus, initially, a continuous layer of uncuzed rubber
reinforced material is positioned and layed around the
mandrel to form a tubular sleeve of material.
Conventionally, a reinforcement cord or filament is then
wrapped about the inner reinforced sheet of rubber
continuously across down the length of the tubular sleeve.
Next, an outer rubber protective layer is stitched and
wrapped about the reinforcement cord or f;lament wrap and
the resultant uncured long layered tube of rubber
reinforced material i~ placed ~n a curing apparatus to
cure the composit~ structure. Therea~ter, cutting knives
are positioned ad~acent the 91eeve to cut predetermined
widths of the timing belt~ off o~ the formed and cured
composite sleeve to produce the dimen~ioned timing belt,
as desired. ~owever, during the cutting operation of the
layered and cured sleeve~ the reinforcement material is
out and exposed at the side~ of the cut belt. Such ex~osed
steel ends behave poorly in use and cause difficulty during
the cutting operation~. Moreover, ~uch structures permit
corrosion and the tende~y of the ~teel filament cord to
move out o~ the side of the belt, to catch moving parts
o~ the mechanical device. Such difficulties result in
a timing belt con~truction which is unsatisfactory and
a timing belt that possesses a short operating lifetime.
It follows that great manufacturing difficulties are
introduced to overcom~ the above described de~iciencies
of having the reinforcement material emerge from the belt
assembly sidewalls.
The above-described drawback~ and shortcomings of
the prior art b~lt con~txuction~ and the conventLonal
method of manufacturing timin~ belt~ and other types of
V-belts or dr$ve belt~, and the secondary di~ficulties
as~ociated w~th the manufacture of such belt structures
will be hereinafter descrlbed with re~erence to FIGS. 1-7.
As shown in FIG. 1, a cylindrical metal mold or
mandrel 18 having longitudinally extending grooves 18a
or teeth 19 on the outer surface thereof is provided as
the former for the belt construction. }n FIG. 2, a strip
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of uncured polymeric mat~ix material 20 is positioned about
the outer surface of the metal mandrel 18 to provide the
year tooth enga~ing wear surface 14 portion of the prior
art belt construction or assembly 301 The strip of
polymeric matrix material 20 may be wrapped several times
around the mandrel 18 to provide a wear and friction
surface portion of a belt assembly and is comprised of
a reinforcing fiber material 22 disposed substantially
uniformly throughout the polymeric matrix material 20 to
provide the year-tooth wear surface portion 14 o the belt
assembly 30. During manufacture, the application of the
strlp of polymeric matrix material 20 is suffic~ent to
provide the desired buildup and thickness of the gear-tooth
wear surface portion of the prior art belt ass~mbly 30.
1~ As shown in FIG. 3, the next step in the known process
for manufacturing a cog or tooth-type belt construction or
assembly 30 is the positioning of the reinforcing cord
or filament 24 about the strip of polymeric matrix material
20. Generally, as described in ~.S. patent 3,188,254,
the rein~orcing cord 24 is spirally spun around the
periphery of the strip of polymeric matrix material 20
and applied under high tension. The reinforcing cord 24
may be of such material such as nylon, rayon, polyester,
glass fibers or steel and the application of the cord about
the mandrel assists the polymeric matrix material 20 in
flowing ~nto the grooves 18a between the longitudinal teeth
19 of the mandrel }8.
A~ter the reinforcing cord or Eilament 24 has been
wound about the mandrel 18, as shown in FIG. 4, an
additional sheet or cover layer 22 of a plastomeric or
rubber material, of a type known to those skilled in the
art, is positioned around the wound reinforcing cord and
matrix material and stitched thereon to complete the raw
- uncured tubular sleeve of belting material. Thereafter,
3~ tubular sleeve and mandrel assembly is positioned in a
conven~ional steam vulcanizing process, which is well known
in the art, to complete the vulcanizing process of the
belt assembly~ During curing or vulcanization, there i5
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addi~iollal flow of rubber or elastomeric material
throughout the composite structure to provide ~ cured
integral belt sleeve, the composite as shown in
cross-sectiOn in FIG. 5. Thereafter, as shown in FIG. 6,
S the cured belt sleeve on the mandrel is removed from "he
curing mold and cut by knives 26 into individual belt
constructions or assemblies 30, as shown in FIG. 7 and
disclosed in U.S. Patent 4,487,814. As shown in FIGS. 3
and 7, becau~e the reinforcing cord or filament 24 is
spir~lly wound about the ~andrel, when the indi~idual belts
are cut from the cured sleeve, the cutt$ng operation
necessar ily provides a plurality of areas on the cut side
of the belt as~embly 30 wh~re the reinforcing cord or
filament 24 is exposed along the side and at the ends, as
shown by 28 in FIG. 7. These exposed ends permit corrosion
within the belt assembly when steel cord is used, which
reduces operating lifetimes of the belt assPmbly 30, and
permit the steel filament or other reinforcing cord to move -~
out of the side of the belt to catch on the mechanical
devices driving the drive belt.
Summary of the Invention
One object of the present invention is to provide a
novel reinforced belt construction which is cut from a cured
belt sleeve wherein the reinforcing cord or filament material
is positioned and sealed within the body of the belt
construction.
The present invention utilizes a reinforcing cord or
filament material comprised of a reinforcing ~ilament or cord
member and a carrier member, which is continuous in length of
~0 the rein~orci.ng material and wherein the rein~orcing cord 1
discontinuous in length over the entire length of the
reinforcing material, which reinforcing material permits the
winding upon a mandrel o~ discrete winds of the rein~orcement
filament or cord separated by discrete winds about the
mandrel of the carrier fiber, which structure permits ~he
subsequent cutting of belt assemblies wherein the reinforcing
filament is positioned and sealëd within the body of the belt
construction.
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The present invention also provides a novel method of
manufacturing belt assemblies or con~tructions which provide
uniform cut belt assemblies without sacrifice of
manufacturing efficiency and productivityO
5~ Brief Descri~tion of the Dra~win~s
FIG. 1 ls a perspective view illustrati~- the
cylindrical ~etal mandrel utilized in manufacturing belt
assemblies or constructionst
FIG. 2 i a per~pective view lllustrating the
application of polymetric matrix mater;~l to t~e metal
mandrel in accordance with the prior art;
FIGo 3 i~ a perspective view illustrating the winding
of a reinforcing cord or filament around the mandrel during
a step in the manufacture of the reinforced belt assembly
in accord~nce with the prior art;
FIG. 4 is a perspectiYe view illustrating the securing
of an outer rubber layer material to the wrapped belt
assembly shown in FIG. 3;
FIG. 5 is a cross-sectional view taken along lines
2 0 5-5 of FIG . 4;
FIG. 6 is a fragmentary isometric view illustrating
the cutting of the belt sleeve a~ter curing to produce
the endless ~ein~orced belt construction in accordance
with the prior art;
FI~. 7 i~ a fragmentary isometric view with parts
in cross section illustrating a typical belt construction
in accordance with the prior artt
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FIG. 8 is a fragmentary isometric view of one
embodiment of a reinforc,ing mater,ial containing a
reinforcing member and a discontinuous portion thereof
having a carrier fiber therebetween in accordance with
the present invention:
FIG. 9 is a cross-sectional view taken along lines
9-9 of FIG. 8;
FIG. 9A is a cross-sectional view taken along lines
9A-9A of FIG. ~;
FIG. 10 is a fragmentary isometric view of still
another embodiment of the reinforcing material having a
discontinuous portion throughout the length thereof and
an extruded covering extending the length thereof in
accordance with the present invention;
FIG. 11 is a fragmentary perspective view illustrating
the cutting of the belt sleeve after curing and cooling
to provide an endless reinforced belt con~tru~ti~n in
accordance with the present invention; and
FIG. 12 is a fragmentary isometric view with par~s
in cross- section illustrating a reinforced belt
constru~tion in ac~ordance with the present invention.
Detailed Description
Referring now to the drawings of FIGS. 8-12, wherein
like numerals have been used throughout the several views
to designate the same or similar parts, in FIG. 8 there
is shown a reinforcing cord or filament material 24 which
is continuous in length and which is comprised of a
reinforcing member 12, discontinuous in length, and a
plurallty o~ carrier member~ or means }6 braided about
the reinforcing member or means 12 and extending the length
of the filament material 24 such that when the reinforcing
cord or filament material 24 is drawn or pulled and
deposited about the mandrel 18, the carrier members 16
confine and pull the reinforcing member 12 therealong.
The carrier member or mean~ may be a tubular or flat braid,
a conventional cable structure, an extruded jacket or a
narro~ thin film tape material.
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FIG. 9 is a cross-sectional view of the reinforcing
cord or filament material ~4, as shown irl F~G. 8~, and
schematically represents a 7 x 3 x 0.0058 inch brass or
zinc plated steel reinforcing cable member 12 which is
substantially centered within four 0.01 inch nylon
monofilament carrier members 16 that have bee~ braide~
around the 7 x 3 reinorcing member 12 member or
construction. As shown in FIG. 8, the reinforcing cord
or filament material 24 is comprised o~ a plurali~y of
carrier membe~ that extend the entire length thereof,
with the reinforcing cable member 12 be~ng discontinuous
in length with respect 'co the reinforcing cord or filament
mal:erial 24 and carrier member~ 16. Alsc, as shown in
FIG. 8, section A represent~ a fir~t -~ection or portion
of ~he r~inforcing cord or filament ~aterial 24 having
four carrier member~ 16 braidet~ about the re~nforcing meta
cable member 12. At the end 12a of the reinforcing member
12, tb~ carrier members continue to ~orm a section or
po~4ion B, which i5 devoid o~ any rainforcing cab~e member
12, and s~ction 8 terminate~ at the end 12a to include
a discrete and predet~r~ned length of the reinforcing
m~terial 24 containing a reinforcing ~ember 12 with braided
carr~er memb~r 16 therearound. FIG. 9A is a schematic
cros -sectional view o~ section B showing the four nylon
~ilament carrier members 16. A~ i~ understood, the overall
length of reinforcing materi~.l 24 will be such that it
may be supplied in coil ~o~m and that the lengtb of section
A would be sufficient to provide the deslred number of
turns or wraps around the mandrel 18.
When such a con~lnuou~ length of reinforcing material
24 is wrapped or wound continuously about a strip of
polymeric matrix material 20 that ha3 been positioned on
the outer surface of a metal mandrel }8 as shown in FIG. 3,
the resultant conf iguration o the wound reinforcing cord
material 24 is depicted and shown in FIG. 11. Tbere,
section B illustrate~ continuous wraps or windings of the
carrier member 16 and section A represents discrete
~ wrappings of the reinforcing material having the
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reinforcing member 12 therein. Thus, after the sheet or
; cover layer portion 22 of the belt asse~bly 10 is
positioned around the wound reinforcing material and
stitched thereon, the resultant sleeve and mandrel are
S placed in a chamber and cured or vulcanized, as is well
known in the art. After curing, knives 26 are positioned
adjacent the cured sleeve and the precise width of
reinforced belt 10 are cut from the cured sleeve. The
knives 2~ engage the cured sleeve in the~ area defined by
section B, between section~ A, to provide the novel
reinforced belt construction in accordance with the present
invention, as shown in FIG. 12. A~ is depicted in FIG. 12,
the sidewalls 10a and 10b (not shown) of the belt assembly
or construction 10 do not have any reinforcing member 12
extending outward}y therethrough and the reinforced belt
assembly or construction 10 provide~ a sea}ed and uniformly
rein~orced belt construct~on wh~ch has herefore.been
unattainable ir. the art. As depicted in FIG. 12, il: is
sho~n that the center within the cut belt assembly 10 are
four con'cinuous wraps o the reinforcing materi21 24
containing the reirlforcing member 12 thereirl with the two
outside wrap~ representi~g the continuou~ carrier member
16 only. Thus, during curing o~ the compos~te reinforced
belt assembly, the carrier members _6 may be comprised
of a cotton-polye~ter ~uilt yarn, such a~ carpet thread,
button thread, nylon or other polymer material which may
possess the property of substantially fusing or interacting
with the cured body portion o~ the belt assembly to
substantially disappear a~ter curing. On the other band,
retention o~ the carrier member identity in the cured belt
sleeve, may be de~irable to facilitate controlling the
ends 12a of the reinforcing member within the cured
composite. Additionally, it may be desired to enhance
the fixation o~ the reinforcing member end 12a to the
carrier member 16 by variety of means, such as, gluing,
heat sealing, auxilliary wrapping or by changing the pitch
of the carrier member overlapping the end 12a o~ the
reinforcement member 12.
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Additionally, it is withi~ the scope of the present
invention that the reinforcing member 1~ may be any type
of carbon steel or other metal cords, such as, stainless
steel, aluminum and the li~e, or may be a cable, tubular
or flat braid, a ribbon or single metal filament and the
carrier members may be glass fibers, aramid fibers, Teflon*
fibers or polyurethane fibers, nylon fibers, or natural
or synthetic yarns in the geometric form of tapes, extruded
or dipped jackets or filaments. Importantly, the
reinforcing member possesses a Youn~'s modules greater
than the Young's modulus of any other component of the
composite belt assembly. For example, a further example
of a useful reinforcement material 24 in accordance with
the present invention includes a reinforcing mem~er portion
comprising S strand cable comprised of 0.010 inch brass
plated stainless steel cord substantially centered within
a carrier member portion comprised of four 0.015 inch~lylon
monofilaments or within four 0.009 inch cotton-polyester
yarn threads. In the present illustration of this
invention, it is preferred that the reinforcing member
12 is discontinuous so as to facilitate forming or cutting
in specific locations within the reinforced belt sleeve
construction. However, it is within the scope of the
present invention that the discontinuity suggested may
be the absence of the reinforcing member over a spe~ific
length of the reinforcing material 24 or may be in the
form in the change in the properties of the rein~orc~ng
member 12 over a specific length o the reinforcing member
24, such as, for example, the reinforcing member or portion
12 may be heat treated or softened and thereby extend
continuously through section B.
FIG. 10 illustrates a further embodiment of the
present invention wherein the reinforcing cord or filament
material 24 includes a reinforcing member or portion 12
comprised of a four wound wire cable. Surrounding or
encapsulating the reinforcing member 12 is a non-metallic
extrudate, c02ting, wrappinq or carrier member 16 which
extends along the entire length of the material 24, with
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the reinforcing member 12 having an end 12a, thereof to
define the gap or section B therebetween. Thus, as
previously set forth, when the reinforcing ~ord or filament
material 24, as shown in FIG. 10, is wound arouna the
mandrel, discrete regions A having the wire reinforcing
member 12 therein followed by discrete wraps of the
non-metallic extrudate 16, as represented by Section B,
and followed by a distinct region of reinforcing member
12 covered by the extrudate, the structure illustrated
in FIG. 11. Such a structure provides a cable reinforced
belt construction 10 having the reinforcing cable or member
12 embedded therein with the outside walls lOa and lOb
being free of a~y reinforcing member cut ends. In such
an embodiment, the extrudate or carrier member 16 may be
a rubber base material, of the same composition of the
reinforced belt construc~ion and upon curing ~hereof,
provides a uniform composite belt assembly or constxu~tion,
as shown in FIG. 12. ~owever it may be desirable to reta n
the extrudation carrier member identity in cured belt
sleeve, to facilitate control}ing the ends 12a of the
reinforcing member 12 withi~ the cured composite. and upon
curing thereof, provides a uniform composite belt
construction. Also, as shown in FIGS. 8 and 10, the
reinforcing member port on 12 of the reinforcing material
24 may be a stranded cable structure having the carrier
members 16 stranded therewith or the carrier members may
be braided about the central core of a strand. Such a
reinforcing material 24 may be produced, for example, on
a flat or tubular braider. It is merely sufficient that
3G the carrier members 16 have sufficien~ strength to retain
the cable member 12 and permit transport and winding of
the same upon the mandel 18, during manufacture. Moreover,
as shown, the braided carrier member 16 may be comprised
of various types o materials and may be comprised of
mixtures of various materials to provide the unique and
novel composite reinforced belt construction in accordance
with the present invention.
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The present disclo5ed reinforcement material 24 having
discontinuous properties over its length has particular
application as a reinforcement material for belt assemblies
and reinforced hose structures~ The reinforcement material
may include a plurality of predetermined lengths of a
reinforcing member 12, as shown in 10, wherein the carrier
member ~6 is affixed to the ends 12a of member 12 and
connects the predetermined len~ths of reinforciny member
12. Such a~fixation may be by shrinking a heat shrinkable
carrier material or by gluing the ends 12a to the
connecting bridge or carrier member 12. One example of
such a construction is a tubular polymer carrier member
12 which is heat shrunk or sealed around the ends 12a of
the cable reinforcing member 12. Such a csnstructio~ of
the reinforcing material 24 provides for the precise
anchoring and retaining of the reinforcing member 12 during
spirally winding of material 24 about the man~rel and
prevents migration of the cable reinforcement during curing
of the assembly.
The present disclosed reinforcement material 24 having
discontinuous properties over its length may be used on
the reinforcement material for polymer based matrix
structures. Examples o~ such structures su~h as a
reinforced hose may be beneficially fabricated with
reinforcement material having discontinous properties in
the vicinity of the hose couplings. ~ tire belt may be
advantageously produced from a reinfarcement material
havin~ discontinuous properties in the vicinity of the
belt edges. Accordingly, the present invention broadly
describes a uni~ue and novel clas~ o reinEorcement
materials that may be incorporated within any polymeric
comoosite assembly requiring termination or geometrical
transition of the reinforcement material.
What has been described is a unique an~ novel
reinforced belt assembly or construction, a novel
reinforced composite assembly and a novel method of
manufacture of such reinforced belt assemblies.
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