Cast Iron Pulleys."
Year: 1897

page_text: Date of Application, 16th Nov., 1897--Accepted, 18th Dec., 1897
"Cast Iron Pulleys."
I, JOHN EDWARD DONOVAN, of 69 Elm Street, Cincinnati, Hamilton County, Ohio,
United States of America, Iron Founder, do hereby declare the nature of this
invention, and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
This invention pertains to cast iron pulleys adapted to be employed as solid
pulleys or as split or divided pulleys. The pulleys are cast and finished in one
piece and may be thus used as solid pulleys, or, if desired, the pulley may be
divided into halves, by breaking operation, before being put into use, or the
pulleys may be put into use on shafts as solid pulleys and later the pulley halves
may be broken apart while on the shaft to facilitate removal, the pulley thereafter
being used as a split pulley. Before the pulley halves are broken apart the pulley
has the full strength of a solid pulley and still the construction is such as to
render possible the easy and correct breaking apart of the halves. When the
pulley is employed as a split pulley the peculiar construction is such that a degree
of strength is gotten which is practically equal to that of the solid pulley. The
joints of contact between the pulley halves, are formed by the original fractures
of breaking as is common in split pulleys and the peculiar construction is such as
to have proper strength of pulley without interfering with the proper intermember-
ing of the fractured surfaces and without distorting the pulley in the act of
bolting the pulley halves together. To adapt the pulley to various sizes of shafts,
bushings are provided which are also cast and finished as single pieces and sub-
sequently broken in two.
In the accompanying drawing Fig. 1 is a face elevation of the improved pulley
(with a bushing) after spliting:
Fig. 2 a perspective view of one of the pulley halves after breaking:
Fig. 3 a side elevation of one of the bushings:
Fig. 4 a perspective view of the pair of bushings belonging to a single pulley,
one-half of one of these bushings being omitted for purposes of clearness, the two
halves of the other bushings being shown as slightly separated: and
Fig. 5 a vertical transverse section of one of the bushings in conjunction with
a shaft.
The pulley rim 1 is maintained full thickness at the points 3 where it is to be
cracked, and ribs 4 project inwardly from the rim at each side of the line of
intended cracking, these ribs 4 forming between them a sharply rooted groove.
Thus when the pulley is to be broken the grooves between the ribs serve in guiding
the crack and at the same time the full thickness of the pulley rim is retained for
intermembering after the cracking has been done.
The rim joints are made secure by bolts 6 passing through lugs 5, there being a
pair of lugs at each end of each joint crack of the rim near the edges of the rim,
the lugs being separated from each other so as not to stiffen the rim and interfere
with such yielding of the rim as may be necessary to permit the fractured surfaces
to properly intermember. Bosses 7 project from the inner faces of the lugs into
contact with each other by fractured surfaces, the bolts 6 passing through these

page_text: bosses, the bosses 7 thus serving to prevent the bolts from distorting the roundness
of the pulley by drawing the lugs closer together than is needed to insure the per-
fection of the joint at the rim, it being understood that the pulley is to be bored
and turned before being broken.
The pulley has the usual arms and in order to secure satisfactory strength from
the arms their roots join into a shallow web extending around the hub as is usual
in solid iron pulleys having arms. Grooves 9 are cast along opposite sides of the
outside of the hub to serve in guiding the cracks in the hub when the pulley is to
be broken, and in in order that these grooves may not destroy the benefits of the
web at the roots of the arms, the grooves pass through the webs as 'mere holes, out-
side of which small portions of the web remain continuous before breaking and
come into fractured contact after breaking. The grooves 9 of the hub are, at the
ends of the hub, sufficiently deep to facilitate breaking, but at the intermediate
portions of the hub the grooves are much deepened so as to leave thin walls at the
roots of the grooves, which thin walls will be cut away in the act of boring the
pulley, the grooves thus becoming slots entirely through the walls of the hub
except at the ends of the hub. The hub halves are drawn together by bolts 10
passing through lugs 8.
The bushings, if bushings are to be employed, are of the form indicated in
Fig. 3, their bodies being of reduced diameter and provided with end flanges 12
which are turned to accurately fit the bore of the pulley, trunnions 14 or 15 pro-
jecting from the body of the bushing to engage openings 20 or 21 in the hub of
the pulley to prevent the rotation of the bushing in the hub. Slots 13 are cast
through the walls of the bushing to facilitate breaking it into halves. Two short
bushings are employed in the hub of each pulley, one at each end of the hub, thus
permitting the bushing parts to better accommodate themselves to inequalities of
the shaft.
The bushings are bored to accurately fit the shaft and each bushing is provided
with the eccentric chamber 16 having end walls or flanges 18, and within each
chamber lies a small roller 17 which is adapted to roll sidewise in the eccentric
chamber and pinch upon the shaft and lock the bushing to the shaft.
In making the pulleys they are cast complete and then bored and turned and,
if desired, fitted with their bolts 6 and 10. The bushings are also cast complete
and bored and their flanges 12 turned. The pulleys may be employed as solid
bushings or they may, when they are to be used, be broken into halves, and the
bushings may be similarly broken. This maintaining of the pulleys and bushings
in unbroken condition until they are to be used, permits them to be used as
unbroken pulleys if desired and also prevents much liability of damage to the
fractured surfaces which should accurately intermember when the halves aro
bolted together. When the pulley is to be put upon the shaft it may, if desired,
be broken apart, and applied to the shaft as a split pulley, or, if desired, it may be
applied to a shaft as a solid unbroken pulley, and if in the future it will facilitate
the removal of the pulley from the shaft, the pulley may be broken apart while in
position and thereafter employed as a split pulley.
Having now particularly described and ascertained the nature of my said in-
vention, and in what manner the same is to be performed, I declare that what I
claim is:-
1. In a split pulley, the combination, substantially as set forth, of a divided rim
and hub with the uniting pulley arms forming two pulley-halves, lugs and bolts
uniting said pulley-halves, and a pair of ribs projecting inwardly from the rim
at each joint crack therein, the inner faces of said ribs being angularly disposed
with reference to each other to form a vee-shaped groove whose root is at the
inner surface of the pulley rim at the joint crack, said rim having normal thick-
ness at the roots of said grooves.
2. In a split pulley, the combination, substantially as set forth, of a divided rim
and hub having the rim united to the hub by arms, lugs and bolts at the hub for

page_text: clamping the hub halves together, a pair of separated lugs projecting inwardly
from the rim at each edge thereof near the ends of the joint cracks in the rim,
the separations between the lugs of each pair straddling the joint cracks of the rim
and the two pairs of lugs at each joint crack being disconnected from each other,
the rim having full normal thickness between the two pairs of lugs at each joint
crack, perforated bosses projecting inwardly from the inner faces of said lugs into
contact with each other, and clamp bolts passing through said lugs and perforated
bosses.
3. In a split pulley, the combination, substantially as set forth, of a rim, a hub,
arms uniting the hub and rim and uniting with each other by a web at the root
of the arms there being longitudinal grooves at opposite sides of the hub and
extending as apertures through said web at the root of the arms, portions of said
web forming outer walls for said apertures, and bolts and lugs for uniting the
pulley halves when the pulley is broken in two.
4. In a split pulley, the combination, substantially as set forth, of a rim, a hub,
and arms uniting said hub, said hub being provided with longitudinal grooves at
opposite sides and extending from end to end of the hub, the central portion of
said grooves being deepened to form slots extending through the wall of the hub
and into the bored hub hole of the pulley, said grooves being shallower at the
ends of the hub, and lugs and bolts at the rim and hub for uniting the pulley-halves
after the pulley is broken in two.
5. In a split pulley, the combination, substantially as set forth, of a divided
rim and divided cylindrically bored hub, lugs and bolts for uniting the pulley halves,
and a boned bushing having a cyindrical body smaller than the bore of said hub
and having at each end a flange concentric with the bore of the bushing and
fitting within the bore of the pulley.
6. In a split pulley, the combination, substantially as set forth, of a divided rim
and divided cylindrically bored hub provided with apertures in its wall, lugs and
bolts for uniting the pulley halves, a bored bushing having its exterior cylindrical
to fit the bore of the hub, and trunnions extending from, the periphery of the bush-
ing into engagement with the said apertures in the bore of the pulley.
7. In a split pulley, the combination, substantially as set forth, of a divided rim
and hub, lugs and bolts for uniting the pulley halves, and a bored bushing having
exterior portions fitting the bore of the pulley and provided with longitudinal slots
extending nearly from end to end of the bushing and through the wall of the
bushing, the wall of the bushing being continuous at the unslotted ends thereof.
8. In a pulley, the combination, substantially as set forth, of a rim, a hub pro-
vided with a bore concentric with said rim and provided at each end with a
chamber eccentric to said bore, and a roller disposed longitudinally within each of
said chambers and adapted to engage between a shaft and the walls of said
chambers.
9. The improved cast iron split pulley having separated pairs of bolting lugs at
its rim and having ribs 4 projecting inwardly from the rim at the lines of intended
breaking, leaving the rim full thickness where it is to be broken, the pulley havng
arms and having its hub grooved and slotted and provided with lugs for bolting.
Dated this 16th day of November 1897.
ALLISON BROS.
Agents for the Applicant.