Method of making a belt

A belt construction and method of making the same are provided, the belt construction having opposed sides and comprising a plurality of teeth defining one of the opposed sides of the belt construction and being mainly formed of a first polymeric material that has reinforcing fibers therein, each tooth having opposed sides that are disposed in spaced relation to adjacent sides of adjacent teeth, the belt construction having a land area between adjacent teeth, and a backing member defining the other of the opposed sides of the belt construction, the backing member being mainly formed from a second polymeric material that is initially separate from the material of the teeth. The method comprises the steps of providing a grooved drum, disposing the first polymeric material in a non-cured form thereof about the drum, then subjecting the drum to heat and pressure to cause the first material to be forced toward the drum and exude into the grooves to at least partially form the teeth, then substantially immediately cooling the first material and the drum to stop the curing of the first material so that the first material is generally in a non-cured condition, then disposing the second material in a non-cured form thereof about the first material on the drum, and then again subjecting the drum to heat and pressure to cause the first and second material to be forced toward the drum to complete any remaining unfinished portion of the teeth and be cured together to form the belt construction.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to an improved belt construction and to a method of 
making the same. 
2. Prior Art Statement 
It is known to make a belt construction having opposed sides and comprising 
a plurality of teeth defining one of the opposed sides of the belt 
construction and being mainly formed of a first polymeric material that 
has reinforcing fibers therein, each tooth having opposed sides that are 
disposed in spaced relation to adjacent sides of adjacent teeth, the belt 
construction having a land area between adjacent teeth, and a backing 
member defining the other of the opposed sides of the belt construction, 
the backing member being mainly formed from a second polymeric material 
that is initially separate from the material of the teeth, the method 
comprising the steps of providing a grooved drum, disposing the first 
polymeric material in a non-cured form thereof about the drum and then 
subjecting the drum with the first material thereon to heat and pressure 
to cause the first material to be forced toward the drum and exude into 
the grooves to at least partially form the teeth. For example, see the 
U.S. Patent to Skura, U.S. Pat. No. 3,078,206 and the U.S. Patent to 
Miller, U.S. Pat. No. 3,535,946. 
It is also known to form toothed belt constructions in separate stages on a 
grooved drum. For example, see the U.S. Patent to Geist et al, U.S. Pat. 
No. 3,250,653; and the U.S. Patent to Wetzel, U.S. Pat. No. 4,235,119. 
While certain of the above-mentioned items form the various layers of a 
toothed belt construction of different polymeric materials, also see the 
U.S. Patent to Cicognani, U.S. Pat. No. 4,445,879 for another such 
multi-layered toothed belt construction. 
SUMMARY OF THE INVENTION 
It is one feature of this invention to provide an improved toothed belt 
construction wherein the polymeric material forming the teeth thereof is 
effectively bonded to the polymeric material forming the backing member 
thereof while having fully formed teeth. 
In particular, it was found according to the teachings of this invention 
that when forcing under heat and pressure a non-cured polymeric material 
that has reinforcing fiber members therein into the grooves of a grooved 
drum to form the teeth of a toothed belt construction, it was desired to 
prevent that material from substantially curing during such forming 
operation so that the same will subsequently effectively bond to the 
polymeric material of a backing member subsequently disposed thereagainst 
and permit the backing material to be forced toward the drum with 
sufficient heat and pressure to completely form the teeth in the grooves 
of the drum. 
It was found according to the teachings of this invention that such curing 
could be substantially eliminated if substantially immediately after the 
step of subjecting the drum to heat and pressure to cause the first 
polymeric material to be forced toward the drum and exude into the grooves 
to at least partially form the teeth, the first material and the drum are 
cooled to stop the curing of the first material so that the first material 
is generally in a non-cured condition when the second material in a 
non-cured form thereof is disposed about the drum and subsequently 
subjected to heat and pressure. 
For example, one embodiment of this invention provides a method of making a 
belt construction having opposed sides and comprising a plurality of teeth 
defining one of the opposed sides of the belt construction and being 
mainly formed of a first polymeric material that has reinforcing fibers 
therein, each tooth having opposed sides that are disposed in spaced 
relation to adjacent sides of adjacent teeth, the belt construction having 
a land area between adjacent teeth, and a backing member defining the 
other of the opposed sides of the belt construction, the backing member 
being mainly formed from a second polymeric material that is initially 
separate from the material of the teeth, the method comprising the steps 
of providing a grooved drum, disposing the first polymeric material in a 
non-cured form thereof about the drum, then subjecting the drum with the 
first material thereon to heat and pressure to cause the first material to 
be forced toward the drum and exude into the grooves to at least partially 
form the teeth, then substantially immediately force cooling the first 
material and the drum to a certain temperature to stop the curing of the 
first material so that the first material is generally in a less cured 
condition thereof than a cured condition thereof if the drum with the 
first material thereon had been permitted to cool to the certain 
temperature at a normal rate by being disposed in substantially static air 
of substantially normal room temperature, then disposing the second 
material in a non-cured form thereof about the first material on the drum, 
and then subjecting the drum with the first and second materials thereon 
to heat and pressure to cause the first and second materials to be forced 
toward the drum to complete any remaining unfinished portion of the teeth 
and be cured together to form the belt construction. 
Accordingly, it is an object of this invention to provide an improved belt 
construction having one or more of the novel features of this invention as 
set forth above or hereinafter shown or described. 
Another object of this invention is to provide an improved method of making 
such a belt construction, the method of this invention having one or more 
of the novel features of this invention as set forth above or hereinafter 
shown or described. 
Other objects, uses and advantages of this invention are apparent from a 
reading of this description which proceeds with reference to the 
accompanying drawings forming a part thereof and wherein:

DESCRIPTION OF THE PREFERRED EMBODIMENT 
While the various features of this invention are hereinafter illustrated 
and described as being particularly adapted to provide a toothed belt 
construction formed of particular materials and with a particular tooth 
profile, it is to be understood that the various features of this 
invention can be utilized singly or in various combinations thereof to 
provide belt constructions formed of other materials and with other tooth 
profiles as desired. 
Further, while the various features of this invention are hereinafter 
illustrated and described as being particularly adapted to provide a belt 
construction in sleeve form which is adapted thereafter to be cut into 
individual endless belts in a conventional manner, it is to be understood 
that the various features of this invention can be utilized singly or in 
various combinations thereof to provide a belt construction which itself 
merely comprises one endless belt, if desired. 
Therefore, this invention is not to be limited to only the embodiment 
illustrated in the drawings, because the drawings are merely utilized to 
illustrate one of the wide variety of uses of this invention. 
Referring now to FIGS. 1 and 2, the improved belt construction of this 
invention is generally indicated by the reference numeral 10, the belt 
construction 10 having opposed sides 11 and 12 and comprising a tensile 
section or means 13 disposed intermediate the opposed sides 11 and 12, a 
plurality of teeth that are generally indicated by the reference numeral 
14 and defining the side 12 of the belt construction 10, and a backing 
member 15 defining the side 11 of the belt construction 10. If desired an 
intermediate relatively thin layer 15A can be disposed between the backing 
member 15 and the tensile means 13. 
While the tensile section or means 13 of the belt construction 10 can 
comprise any suitable structure, the embodiment thereof illustrated in the 
drawings comprises a plurality of side-by-side cords or strands formed of 
a suitable substantially non-stretchable material in a manner conventional 
in the belt-making art as will be apparent hereinafter and therefore the 
terms "tensile means" will be hereinafter utilized for describing the 
tensile section 13 of the belt construction 10. 
The teeth 14 of the belt construction 10 are mainly formed of a first 
polymeric material 16 that has reinforcing fibers 17 therein, each tooth 
14 having opposed sides 18 and 19 that are disposed in spaced relation to 
adjacent sides 19 and 18 of adjacent teeth 14. The sides 18 and 19 of each 
tooth 14 are shown as being flat and angled relative to the longitudinal 
axis of the belt construction 10 that is disposed parallel to the tensile 
means 13 and can comprise the driving or driven parts of the teeth 14 in a 
manner well known in the art. However, it is to be understood that the 
cross-sectional configuration of the teeth 14 can have any other suitable 
profile rather than being substantially trapezoidal as illustrated in 
FIGS. 1 and 2, if desired. 
The belt construction 10 has land areas that are generally indicated by the 
reference numeral 20 in FIGS. 1 and 2 and are respectively disposed 
between adjacent teeth 14 as is conventional in the art. 
The intermediate layer 15A of the belt construction 10 is mainly formed 
from a polymeric material 21A that is initially separate from the material 
16 of the teeth 14 and has reinforcing fibers 17A therein as illustrated 
in the drawings, the material 21A of the layer 15A having a surface 22A 
that joins with a surface 23 of each tooth 14 whereby the joining surfaces 
22A and 23 define an interface line 24 therebetween that is substantially 
coplanar with the surface 25 of the tensile means 13 but may dip into the 
medial portion of each tooth 14 in a manner similar to the interface line 
for each tooth of the belt construction set forth in the aforementioned 
U.S. Patent to Wetzel, U.S. Pat. No. 4,235,119 and applicants' copending 
patent application, Ser. No. 502,777, filed June 9, 1983, whereby this 
patent and this copending patent application are being incorporated into 
this disclosure by this reference thereto. 
The surface 22A of the layer 15A also joins with a surface 30 of the first 
material 16 in each land area 20 whereby the joining surfaces 22A and 30 
in each land area 30 define an interface line 31 therebetween that is also 
substantially coplanar with the surface 25 of the tensile means 13. 
However, it is to be understood that the interface line 31 in each land 
area 20 of the belt construction 10 of this invention can be disposed 
substantially adjacent the side 25 of the tensile means 13 as illustrated 
in FIG. 2 or could extend spaced from that side 25 toward the side 11 of 
the belt construction of FIG. 1 as in the aforementioned copending patent 
application, Ser. No. 502,777, filed June 9, 1983, or be disposed 
intermediate the two sides 25 and 26 of the tensile means 13 depending 
upon the original thickness of the first material 16 utilized to form the 
belt construction 10 as will be apparent hereinafter. In this same vein, 
the interface line 24 between the materials 16 and 21A in the medial 
portion 27 of each tooth 14 could be disposed completely intermediate the 
sides 25 and 26 of the tensile means 13, be substantially even with the 
side 25 of the tensile means 13 or be intermediate the side 25 of the 
tensile means 13 and the side 11 of the belt construction 10, again 
depending upon the initial thickness of the material 16 being utilized and 
the degree of completeness of the teeth 14 during a first forming step of 
applying heat and pressure to initially form the teeth 14 as will be 
apparent hereinafter. 
In any event, it can be seen that the interface line 24 for each tooth 14 
of the belt construction 10 of this invention, as well as the interface 
line 31 for each land area 20 of the belt construction 10, is disposed 
spaced from the side 26 of the tensile means 13 so as to tend to remove 
any tendency of a shearing effect to take place at the interface lines 24 
and 31 along the side 26 of the tensile means 13 as the only portions of 
the interface lines 24 and 31 between the materials 16 and 21A that might 
actually cross the side 26 of the tensile means 13 would be disposed at an 
angle relative to the side 26 of the tensile means 13 in the medial 
portion of each tooth 14 and, thus, would tend to oppose any shearing 
forces being applied to the teeth 14 during the driving or driven 
operation of the belt construction 10 in a manner that is well known in 
the art. 
Further, it can be seen that substantially the entire portion of the teeth 
14 of the belt construction 10 disposed below the side 26 of the tensile 
means 13 have the reinforcing fibers 17 therein which tend to prevent 
and/or oppose a shearing force from shearing the teeth 14 from the belt 
construction 10. Thus, such a belt construction 10 is particularly adapted 
for being a synchronous belt as will be apparent hereinafter. 
The backing member 15 of the belt construction 10 is mainly formed from a 
second polymeric material 21 that is initially separate from the materials 
21A and 16 and can be substantially free of reinforcing fibers therein, if 
desired, as illustrated in the drawings, the material 21 of the backing 
member 15 having a surface 27 that joins with a surface 27A of the layer 
15A and will follow that even contour the layer 15A takes in its joining 
with the first polymeric material 16 in the land area 20 and the teeth 14 
as previously set forth. 
If desired, a conventional reinforcing fabric material 36 can be utilized 
to cover the opposed sides 18 and 19 of each tooth 14 as well as cover the 
bottom surface 37 of each tooth 14 and the bottom surface 38 of each land 
area 20 as illustrated in FIGS. 1 and 2. 
The belt construction 10 illustrated in FIGS. 1 and 2 and previously 
described is formed by utilizing a method and apparatus of this invention 
that is similar to, but uniquely different from, the method and apparatus 
disclosed and described in the aforementioned U.S. Patent to Skura, U.S. 
Pat. No. 3,078,206 and the aforementioned U.S. Patent to Miller, U.S. Pat. 
No. 3,535,946 whereby these two patents are being incorporated into this 
disclosure by this reference thereto. 
For example, reference is now made to FIGS. 3 and 4 wherein the method and 
apparatus of this invention for making the belt construction 10 of FIGS. 1 
and 2 is generally indicated by the reference numeral 40 and comprises a 
metallic drum 41 that has a plurality of longitudinally disposed and 
spaced apart parallel grooves 42 therein in which the teeth 14 of the belt 
construction 10 are subsequently formed. 
The grooved drum 41 is formed and utilized in substantially the same manner 
as set forth in the aforementioned Patent to Skura, U.S. Pat. No. 
3,078,206 and therefore the details thereof need not be set forth. 
When forming the belt construction 10 of this invention, the stretchable 
fabric cover 36 is first disposed or wrapped about the drum 41 with the 
opposed ends of the fabric cover 36 either being butt joined or overlapped 
as desired in a conventional manner. 
Thereafter, a layer of the first polymeric material 16 in a non-cured form 
thereof is disposed or wrapped about the drum 41 on top of the cover 36 
and has the opposed ends 45 and 46 thereof disposed in abutting relation 
as represented by the butt line 47 in FIG. 3. 
Thereafter, a heat shrinkable tensile simulating means 43 is disposed on 
top of the first polymeric material 16 by suitably winding one or more 
cords 44 of the tensile simulating means 43 on the first polymeric 
material 16 with adjacent turns 44 of the tensile simulating means 43 
being spaced from each other the desired distance or combination of 
distances, FIG. 3 merely being a schematic showing of such spacing which 
will correspond to the desired spacing for the particular tensile means 13 
subsequently utilized for the belt construction 10 as will be apparent 
hereinafter. 
While the fibers 17 in the polymeric material 16 can be randomly and 
homogeneously disposed therein, it is also possible that the fibers 17 can 
be oriented throughout the material 16 and in the embodiment illustrated 
in the drawings, the fibers 17 in the material 16 have been oriented so 
that their long dimensions will mainly extend in a direction between the 
opposed sides 18 and 19 of each tooth 14 as illustrated in FIG. 2 and, 
therefore, are disposed in a direction that is transverse to the 
longitudinal axis of the drum 41 as illustrated in FIG. 3. 
After the parts 36, 16 and 43 of the belt construction 10 have been 
disposed in the wrapped-around condition on the drum 41 as illustrated in 
FIGS. 3 and 4, such assembly is disposed in the apparatus that is 
generally indicated by the reference numeral 48 in FIG. 5 and comprises a 
container 49 having a chamber 50 therein. One end 51 of the drum 41 may 
rest against a resilient sealing gasket means 52 disposed on an end wall 
53 of the container 49 and a removable cover member 54 is disposed against 
the other end 55 of the drum 41 so that the interior 56 of the drum 41 can 
have steam injected therein and/or be vented through a valve means 57. A 
flexible diaphragm 58 in cylinder form is disposed about the drum 41 and 
has its inner surface 59 disposed against the cord 43 and adjacent the 
outer surface 60 of the polymeric material 16 while its opposed ends 61 
and 62 are respectively disposed in substantial sealing engagement with 
the end gasket 52 and an outwardly extending flange 63 of the cover means 
54. In this manner, the flexible diaphragm 58 is adapted to force the cord 
43 and material 16 toward the drum 41 when steam under a suitable pressure 
is directed into the chamber 50 of the container 49 through suitable valve 
means 64 to act on the exterior 65 of the diaphragm 58 in a manner fully 
set forth in the aforementioned Patent to Skura, U.S. Pat. No. 3,078,206. 
The steam that is directed into the interior 56 of the drum 41, if used, 
has a pressure value that is less than the pressure value of the steam 
that is directed into the chamber 50 through the valve means 64 so that 
the resulting pressure differential between the interior 56 and the 
exterior 50 of the diaphragm 58 causes the diaphragm 58 to force the cord 
43 and material 16 toward the drum 41 and since the material 16, as well 
as the fabric 36, has been heated by the steam, the same exudes toward the 
drum 41 into the grooves 42 to at least partially form the teeth 14 in the 
manner illustrated in FIG. 6 wherein unfilled gaps 66 of the grooves 42 
remain when the diaphragm 58 comes to rest against the top surface 33 of 
the cords 43 as illustrated in FIG. 6, the heat shrinkable cords 43 having 
been shrunk by the heat and having been embedded into the surface 60 of 
the polymeric material 16 as illustrated in FIGS. 6 and 8 thereby defining 
the location of the pitch line of the belt construction. 
At this time, the heat required to permit the material 16 and cover 36 to 
exude into the grooves 42 of the drum 41 is sufficiently high so that the 
same will begin to cause the material 16 to begin to cure so that it is 
desired according to the teaching of this invention to substantially 
immediately cool the drum 41, material 16, cover 36 and cords 43 and this 
is accomplished by removing the drum 41 with the material 16, cords 43 and 
cover 36 in the condition illustrated in FIG. 6 and dispose the same in a 
cooling bath that is generally indicated by the reference numeral 67 in 
FIG. 7. The cooling bath 67 immediately reduces the temperature of the 
drum 41, material 16, cords 43 and cover 36 to at least a temperature 
where the aforementioned curing operation immediately stops so that the 
material 16, cords 43 and cover 36 will now be at generally a non-cured 
condition thereof. 
For example, it is believed that the temperature of the material 16, cords 
43, cover 36 and drum 41 can be lowered to approximately 140.degree. F. to 
substantially stop the aforementioned curing operation. Of course, the 
temperature can be lowered to a temperature lower than 140 F., if 
desired. 
While the bath 67 can have any suitable cooling fluid 68 therein, the same 
can comprise water that is normally maintained at room temperature. 
Once the drum 41 and its associated means 16, 43 and 36 have been cooled in 
the above manner, the cord 43 is removed as illustrated in FIG. 8 and the 
water on the exterior surface 60 of the material 16 is removed in any 
suitable manner, such as by blowing hot air on the same, etc. In this 
manner, the surface 60 is sufficiently dried so that a subsequent 
securement of the layer of material 15A thereto can take place as will be 
apparent hereinafter. 
The tensile means 13 is now laid into the resulting grooves 43' that had 
been formed in the surface 60 of the polymeric material 16 by the 
shrinkable cords 43. 
Subsequently, the layer of material 15A in a noncured form thereof, if 
used, is now disposed or wrapped on top of the tensile means 13 and 
polymeric material 16 in the manner illustrated in FIG. 9. Thereafter, the 
second polymeric material 15 is disposed or wrapped on top of the layer 
15A and then the drum 41 with the materials 15 and 15A thereon in the 
manner illustrated in FIG. 9 is disposed back into the container 49. The 
diaphragm 58 is now disposed against the outer surface 70 of the material 
15 so that a subsequent heating and pressing operation can be provided in 
the container 49 to cause the materials 15, 15A and 16, as well as the 
cover material 36, to be forced toward the drum 41 to cause the material 
15A to embed into the tensile means 13 and completely mate with the 
surface 60 of the material and cause the material 16 and cover 36 to 
substantially fill out all remaining voids 66 in the grooves 42 to 
completely form the teeth 14. In addition, the heat and pressure is 
maintained in the container 49 for a sufficient period of time to cause 
the material 16, 15A and 15 to cure together and form the interface line 
24 as previously set forth. Also, at this time, the cover 36 fully bonds 
to the material 16 of the teeth 14. 
It is believed according to the teachings of this invention that since the 
material 16 is in generally a non-cured condition, as well as the cover 
36, when the material 15A is being forced against the same to complete the 
forming of the teeth 14, the material 15A bonds or adheres to the material 
16 to a greater degree when the material 16 is in a generally non-cured 
condition than when the same is in a more cured condition at the time the 
material 15A is being heated and pressed against the material 16 for this 
purpose. 
Of course, if the layer 15A is not utilized, then the layer 15 will bond to 
the surface 60 of the layer 16. 
Once the materials 15, 15A, 16 and 36 have been completely cured in the 
manner previously set forth, the drum 41 is removed from the container 49 
and the belt construction 10 is then removed from the drum 41 and further 
processed in a conventional manner. 
For example, if the belt construction 10 comprises an elongated belt sleeve 
as previously described and illustrated in the drawings, the same can be 
cut into the individual endless belts in a conventional manner whereby 
such operation need not be further described. 
Therefore, it can be seen that this invention not only provides an improved 
belt construction, but also this invention provides an improved method of 
making such a belt construction. 
While the particular material of the belt construction 10 of this invention 
can be selected so that the same will provide a suitable belt construction 
10 when made according to the method of this invention, one such belt 
construction that has been successfully made by this invention comprises a 
synchronous belt for a motorcycle final drive. Such belt has a thickness 
of approximately 0.300 to 0.400 of an inch, each tooth 14 having a base 
width of approximately 0.312 of an inch, a depth of approximately 0.185 of 
an inch, each side 18 and 19 being angled at approximately 9 degrees 
relative to the center line of the respective tooth 14, a root radius of 
approximately 0.050 of an inch and a bottom radius of approximately 0.070 
of an inch. The polymeric material 16 of such belt comprises a neoprene 
rubber loaded with nylon fibers of relatively short length and being 
approximately 40 parts fiber per 100 parts rubber (40 PHR), such fibers 
having a diameter in the approximate range of 0.001 to 0.050 of an inch 
and a length in the approximate range of 0.001 of an inch to as much as 1 
inch, the material 16 having a Mooney minimum of approximately 19.5 at 
275.degree. F. and an original gauge or thickness of approximately 0.130 
of an inch. The ply 15A was formed of the same material as the layer 16 
and had an original gauge of approximately 0.060 of an inch. The material 
15 of such belt comprises a neoprene gum stock which is substantially free 
of fibers therein and has a Mooney minimum of approximately 9.5 at 
275.degree. F. with an original gauge or thickness of approximately 0.050 
of an inch. The fabric cover 36 for such belt is a stretchable RFL 
(resorcinal formaldehyde latex) treated nylon fabric which has a raw 
fabric weight of approximately 101/2 to 12 ounces per square yard thereof. 
It was found that the nylon fabric required an RFL treatment so as to have 
a lower curing rate over other coated fabric material so that the teeth 14 
will fully form according to the teachings of this invention in the manner 
previously set forth. The tensile means 13 for such a belt construction 
comprises a fiberglass cord 140 Tex 1/3/12 having a diameter of 
approximately 0.082 of an inch and such cord is wrapped so as to provide 
approximately 8 cords per inch across the face of the drum 41. The 
shrinkable cord 43 that was removed after forming the grooves 43' 
comprises a greige or raw unprocessed polyester cord that had an effective 
diameter of approximately 0.082 of an inch. 
When forming such a belt construction, the drum 41 and its associated 
materials 43, 16 and 36 utilize approximately a 5 minute warmup time in 
the tank 49 wherein the steam pressure inside the drum 41 is approximately 
50 psi and the steam pressure outside the drum 41 is approximately 120 
psi. This is followed by approximately a 5 minute forming cycle of heat 
and pressure wherein the outside steam pressure is approximately 120 psi 
with the inside pressure being approximately 0 psi. The drum 41 and its 
associated materials 43, 16 and 36 is then placed in the cooling bath 67 
for approximately 10 minutes. Thereafter, the final curing operation of 
the cooled drum 41 in the tank 49 with the means 43 removed and the 
materials 15, 15A and 13 applied has an outside steam pressure of 
approximately 75 psi and an inside pressure of approximately 0 psi for 
about 10 minutes followed by the outside steam pressure being 
approximately 120 psi and the inside steam pressure being approximately 0 
psi for about 5 minutes followed by the outside steam pressure being 
approximately 120 psi and the inside steam pressure being approximately 50 
psi for about 45 minutes whereby the total final cure time is about 60 
minutes. 
Therefore, it can be seen that by following the teachings of this invention 
a high modulus high Mooney compound can be successfully formed into a 
synchronous belt by preforming the teeth on a mold or drum before the 
application of a tensile means and a gummed backing material. 
For example, in the aforementioned example, the high modulus material 16, 
approximately 5,000 psi at 50% elongation, was made to make a synchronous 
belt for a motorcycle final drive and tests show a standard belt to 
deflect and jump teeth in less than 20 jam cycles whereas the belts of 
this invention were run at least 6000 cycles without jumping and shearing 
and when removed therefrom, little wear thereon was noticed. 
It is to be understood that the above specific example of a particular belt 
construction 10 formed according to the teachings of this invention is not 
to be a limitation on this invention but is merely for the purpose of 
illustrating how one such belt construction was formed according to the 
teachings of this invention. 
For example, it is believed that other high modulus materials, such as 
thermoplastic materials, could be utilized in combination with backing 
members of lower modulus material in the method of this invention to form 
toothed belt constructions. Of course each material would probably need 
different forming times, temperatures and pressures. 
Therefore, it can be seen that this invention not only provides an improved 
belt construction, but also this invention provides an improved method of 
making such a belt construction or the like. 
While the forms and methods of this invention now preferred have been 
illustrated and described as required by the Patent Statute, it is to be 
understood that other forms and method steps can be utilized and still 
fall within the scope of the appended claims wherein each claim sets forth 
what is believed to be known in each claim prior to this invention in the 
portion of each claim that is disposed before the terms "the improvement" 
and sets forth what is believed to be new in each claim according to this 
invention in the portion of each claim that is disposed after the terms 
"the improvement" whereby it is believed that each claim sets forth a 
novel, useful and unobvious invention within the purview of the Patent 
Statute.