Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
1090616
This invention relates to toothed transmission drive belts
such as timing gear belts, or the like, to provide for positive, non-slip
drive. Toothed belts having teeth are already known. The usual type of timing
belt known to the art requires pulleys having side flanges to prevent the
belt from "walking offl' the pulleys.
According to the invention, a drive transmission means is
provided comprising at least one cable, belt means surrounding said cable,
and having a series of similar teeth formed therein, said belt means also
including a plurality of guide portions extending between pairs of adjoining
teeth forming an intermittent longitudinal belt guide means, and said teeth
bcing formed along one side of the belt means and the other side of the
belt means having a recessed portion positioned opposite each tooth. ~-
DETAILED DESCRIPTION
Embodiments of the invention are illustrated in the accompanying
drawings, in which:
FIGURE 1 is an elevational view;
PIGURE 2 is an enlarged perspective view of the belt of PIGURE 1
with parts cut away;
FIGURE 3 is an enlarged sectional detail along the lines 3-3
in FIGURE l;
FIGURE 4 is a view similar to FIGURE 2 illustrating a second
form of transmission belt according to the invention;
FIGURE 5 is a sectional view along the lines 5-5 in FIGURE 4;
FIGURE 6 is an elevational view of the belt of FIGURE I in
looped end facing relationship prior to being spliced into an endless loop
with parts cut away;
.~
6 16
Fig~ 7 i8 an elevational view ~milar to Fig. 6 Jhowing
a step in the splicing of the belt;
Figo 8 is an elevational view showing a further step
in splicing which inclute~ the positioning of a bushing; and
Fig. 9 i8 an elevational view ~howing the splice com~
pletet with the bushing installed.
Similar numerals refer to similar part~ throughout th
several view8~ ~
The drive tran~mission means of the invention 20 com- -
prises a main body portion fonmed by at least one eLongatet flexi- -
ble bod~ element 22 which in turn comprises a central cable 241i
madc up of multiple ~trands 26 of twi~ted ~teel, wire or other
~uitable material, and covering ~ean~ ~uch aJ a pl~tic cable
~acket 28, preferabl~ of soft flexible grade pol~ureth~ne, or
nylon, which i~ e~truded or ~oldet around the cable 24 b~ any of
the well known mean~ kn Q to the art,
Belt means 30 m~y be extruded or lded over the cover- -
ing mean~ 28 by any meanJ known to ~e art, or tke cable c0ver 28
and the belt ma~ be fashioned integrally as a combination cable
covcr and belt 30~9 a~ Jh0wn in Fig~o 4 and 5.
~elt covering mean~ 30 and 30a are provided with indented
portion~ 36 which form teeth 389 Thi~ provides for ~ firm yet
flexible con~truction having ~trength and having teeth 38 which
are adapted to mesh within the cavity 40 of the teeth 42 of
toothed tran~mi~ion wheel mean~ Juch a~ pulley~ 44 to drivo the
pulleyJ 44 who~e teeth 42 al~o fit within the cavitie~ 46 for~ed
between the teeth 38 of the belt meanJ 30 or 30a~
The con~truction of the belt me~n~ 30 or 30a alJo
~rovides for belt guide mcans 48 adapted to fit groove me ns 50
-- 2 --
~ 6
in the pulley teeth 420 Guide mean~ 48 are made up of a series
of arc-like belt guide portions 52 positioned in the cavitie~
46 between the belt teeth 38. Portion~ 52 have an arc-like
configuration having a curved surface portion 54 concentric
to the portion of cable 24 which it cover~. Thu~ the con~truc-
tion comprising the integral belt and cover 30a or the belt 30
and ~acket 28 over the cable 24 with the teeth 38 and the belt
guide portions 52 provide a transmission belt means 20 having
a positive drive for a toothed pulley 44 and also having belt
guide means 48 to prevent the belt from '~alking off" the pulley
440
This construction eli~inate~ the neces~ity of expensive
side flanges for the pulley 44 to hold the b-lt 20 in place, which
also would require maintenance, and provides a strong, light-
weight, ant e~tremely flexible belt 20 which nevertheles~ bas
po~itive driveO
The belt may have a smooth ~ide 60 opposite the toothed
side 62 of the belt means 30a, as shown in Fig. 4, or, if desired,
reces~ed portionJ 64, opposite the indented teeth 38, may be pro-
vided as in belt means 30 shown in Figo 20
It i8 to be under~tood that all belts of the inventionmay be m~de with one or more cables in side by ~ide relationship,
as shown in either Fig. 2 or 4, and either with integral belts
3~a or with two or more layers of materi~l aa in belt 30, and
with or without recessed portions 64.
Where there i~ a belt having two or more cables 24,
belt duide means 48 and grooves 50 may be provided with relation
to each cable 24 (see Fig. 5)~
~ D~ 1 6
The transmiJ~ion belt 20 iJ mude in selected length~
as desired for splicing into endless belts 20 of de~ired ~ize~.
The ~plice is made as illu~trated in Fig~o 6 through 9 of the
drawings. In Fig. 6 a single length of a tran d ~ don belt 20
i~ shown whlch has be~n coiled around to form an endles~ loop
with its ends 70 and 72 in end facing relation~hip. In Figs.
6 through 9 only the ends 70 and 72 of belt 20 are ~hown ~ince
the balance of the belt 20 has been cut away in the-e figures.
In order to ~plice the belt 20 80 that the teeth 38
will fit ~ithin the cavities 40 of the pulleyJ 44, provision
must be made to spac- the two teeth 38E ad~oining the splice -~
area 74 to be po~itioned properly with the splice 76 taking up
the sp-ce required by one toothed belt Jection 38S. This i8
acco~pli~hed by providing a length of belt 20 baving nd ~or-
tion~ 70 and 72 which include belt tooth soction- 38S whlch
are overlapped to form the splice 76 of tbe as~e length as a
~ingle belt tooth ection 38So
A belt tooth aection 38S ia defined a~ th~t x~ection
or unit o belt 20 J~arting at tbe center line 78 of a cavity
~0 46 and ending at the center line 78 of the ne~t cavity 46 and
including tbe tooth 38 poJitioaed bet~oen ~aid cavity 46 and
center~ 78.
Let it be as~umed that bolt 20 would require 28 belt
tooth section~ 38S to drive bet~een t~o pulleys 44 8~ in F~g.
1. Since the ~plice 76 must tske the place of one belt tooth
Jection 38S and ~ince it i~ neceJssry for end~ 70 and 72 to
overl~p in mak~ng the splice 76, the length of belt 20 neces-
sarily would contain the Jplice 76 plus twenty-~even belt
tooth sections 38S. The splice apace 76 is equal to t~o ~elt
tooth ~ections 38S which are overl pped into the ~plice 760
Thus a length of belt for ~ ~ystem requiring twent~-eight
tooth sections 38A would actuslly need twenty-nine tooth sec-
tion~ 38A, or one estra to ~ake the splice 76.
The first step in splicing is to provide a proper
size belt length, a~ de~cribedO The second step in splicing
i~ to cut all of the ~acket 28 and cover material 30, or the
belt material 30a, from the cable 24 to lay bare cable ends t
80 and 82 for the length of the end of tooth sectioQ~ 38S, as
in Figo 7O The next ~tep i~ to tri~ ends 80 and 82 a small
umount (between approximately 5 to 15 per cent of the end 80
and 82 lengths) as shown by the dotted lines at 84 and 86 in
Figo 70
The next step is to overlep the cut cable end~ 80 and
82 between end tooth units 38E to make a splice sp-ce 74 of
the length of a dngle belt tooth ~ection 38S, and tben a ~tep
of placing an open ~plice bu~hing 88 over the overlapped cable
ends 80 and 82, as ~hown in Figo 80 The final step of the
~plice is to crimp the open bu~hing 88 with a C~t~piQg tool or
by oth¢r means to force bind the cable ends 80 and 82 together
in positive arrangement by closing the bushing 880
The splice 76 will ride along over the pulleys 44
with the belt 20 and, if properly made wlth the ~plice 76 of the
s#me length as a ~ingle belt tooth section, will ride over a
pulley cavity 40O Thus the completed belt loop will pre~ent
teeth 38 to the pulley cavities 40 with the exception of the
one belt length comprising the splice. Since there wlll be a
plurality of teeth engaging each pulley, Rkipping one space for
-- 5 --
~ 6 1 6
the splice will not affect the efflci~ncy or u~eabilit~ of the
belt~ of the invention.
In addition to the advantage~ alread~ entioned
there i~ a further dvantage in the stre~gthening of the c-ble
of thc invention in that the materi-l of the ~acket 28, which
iJ e~truded or molded around the cable 24, wlll be fill d into
the space~ 90 around the outer strand~ 26 of the cable 24 and
may al~o be filled into all of the Jpace~ ~uch aJ 92 within ~ ',!,
the cable 24 bet~een the trand~ 26 of the cable 24 which co~
munic-te with the outer surf-ce of the cable.
~ hile I h~ve de-cribet ~ invention in its preferred
form there are many for~s that lt may take and I desire to be
pr0tected for all fonms coming within the scope of the ~laim~
hereinbelow. ~ -
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