IMPROVED CAST METAL PULLEYS AND THE METHOD OF MANUFACTURING THE SAME
Year: 1876

page_text: LETTERS PATENT to Peter Jensen, of Chancery Lane, London, for the Invention
of "IMPROVED CAST METAL PULLEYS AND THE METHOD OF MANUFACTURING
THE SAME." A communication from abroad by Augustus Lea Bricknell, a
citizen of London, England, but at present residing in Nashville, in the County
of Davidson and State of Tennessee, and Alexander Allison Hall, of said.
Nashville, County of Davidson and State of Tennessee, both in the United
States of America.
Sealed the 28th March 1877, and dated the 9th November 1876..
COMPLETE SPECIFICATION filed by the said Peter Jensen at the Office of the
Commissioners of Patents on the 9th November 1876.
"
PETER JENSEN, of Chancery Lane, London. IMPROVED CAST METAL PULLEYS
AND THE METHOD OF MANUFACTURING THE SAME." A communication from abroad
by Augustus Lea Bricknell, a citizen of London, England, but at present residing
in Nashville, in the County of Davidson and State of Tennessee, and Alexander
Allison Hall, of said Nashville, County of Davidson and State of Tennessee, both
in the United States of America.
This Invention has for its object the economical production of cast-metal belt
pullies having belt faces, which are well finished and practically concentric with.
their axes, and this is accomplished without the expensive machine work heretofore
necessary for producing pullies having the recited characteristics.
It is well known that owing to the unequal contraction of the metal, solid cast-
iron belt pullies have belt faces which are irregular in their outline and not truly
concentric to their axes, and although such pullies are sometimes used without the
expenditure of lathe work on their faces, their service is far from satisfactory, and
they are never employed in first class mills or factories.
It is also well known that solid cast-iron pullies are frequently unduly strained
either at the arms or rim, or both, so that although apparently perfect and of the
required strength, they are very liable to burst or break on receipt of any sudden
strain or shock. To obviate this difficulty large cast-iron pullies are sometimes cast,
in segmental sections; subsequently-fitted-and-united, and their faces finished off in
a turning engine or lathe..

page_text: This Invention consists mainly in casting the rim of a belt pulley in one piece,
the hub and arms or their equivalents in one or more pieces, preferably in one piece,
and in uniting the rim thereto while adjusted and maintained in a position con-
centric with the hub.
This Invention further consists in casting the rim of a belt pulley in a mould
having a smooth well finished permanent face moulding surface, and a yielding non-
chilling core, whereby a belt face is attained which requires no machine finishing,
and the irregular and uneven contraction of the metal is practically obviated.
Belt pullies made in accordance with this Invention are readily distinguishable
from any others heretofore made.
And this Invention further consists in a belt pulley having a solid separately cast
rim, which is united to the hub and arms by any suitable means.
It has been demonstrated by practical operations that a pulley constructed in
accordance with this Invention is much less expensive than pullies solidly cast, as
heretofore, because the operations of moulding and casting are greatly simplified,
and it requires no machine work on its face either for attaining a desirable belt
surface or for securing concentricity. These pullies too are stronger than those
which are cast solidly, because they are never under that strain which is incident
to the contraction of cast metal.
It will be obvious, so far as the casting is concerned, that pullies cast in seg-
mental sections are more costly than those cast solidly, but if there be more than
one arm in any one section, the strain due to contraction exists to a greater or lesser
extent. The segmental pullies also require machine work on their faces to secure
concentricity and to afford a proper belt surface. As compared with these segmental
sectional pullies, these are cast at a much less cost, and require, as before stated, no
machine work on their faces.
For permanent face mould surfaces I can employ any of the well-known matters
and compounds; for instance, plaster of Paris, plumbago, &c.; or as in practice is
prefered, a cast-iron chill may be employed.
To more particularly describe this Invention I will refer to the accompanying
Drawings, of which two Sheets are furnished.
Figure 1 represents in perspective a mould such as I prefer to employ for forming
a suitable core.
Figure 2 represents the same in diametrical vertical section.
Figure 3 represents in sectional view the sand core and chills in proper position,
and a cast pulley rim remaining in the mould.
Figure 4 represents in perspective one of the improved pullies.
Figures 5, 6, 7, and 8 represent different forms of joint between pulley arms and rim.
Figure 9 represents a pulley having a solid web instead of arms.
Figure 10 represents a hub and its arms.
Figure 11 represents in perspective a chill, bottom side up.
Figure 12 represents in perspective a circular base plate, right side up.
Figure 13 represents in section a centering table such as I prefer to employ for
adjusting the parts of which the pullies are composed, and for maintaining them in
proper position while being united.
Referring to Figures 1 and 2, A denotes a base block which constitutes the
bottom of the mould. A vertical cylinder, as at a, is mounted centrally thereon for
the purpose of obviating the use of a greater quantity of sand than is actually
requisite for forming a suitable core. Moreover, the core thus formed is better
adapted to afford a more uniform resistance to the contraction of the metal in cooling
than would be the case if no central block was employed. B denotes a sectional
cylindrical shell or core box, which constitutes the vertical sides of the core mould.
Preferably this shell will be made in two pieces, each being semicircular and of such
a height as will render them available for casting pullies with as wide a face as
would ever be required on pullies of a diameter equal that of the mould. The
shell B is provided with apertures bat intervals for the reception of detachable
prints c; these prints will be of such form and dimensions as may be required in

page_text: each case for providing at the inner side of the rim of the pulley a point of con-
nection with the hub or its arms.
For making pullies with one scries of arms the outside of the shell is provided
with an outwardly projecting flange, as at c¹, located midway between top and
bottom, and the lower sides of the print apertures bare in the same plane with the
upper side of the flange c¹, so that the prints c will have a good bearing or support
thereon.
In some instances the prints are made in one piece when capable of easy draft,
and sometimes in two pieces, in which case they are confined in position by means
of a cross bar, as at d, and a clamp screw passing through the flange.
When the prints are in two pieces and set angularly to each other I provide
recesses in the flange and projections on the prints, so that the prints may be readily
and accurately adjusted with relation to each other. The parts or sections of the
shell are united by means of flanged ears and bolts.
When the shell is arranged for making pullies with two series of arms, it is
provided with a flange adjacent in like manner with each series of print apertures b.
It is obvious that the depth of the prints may be varied.
Referring next to Figure 3, C denotes a circular cast-iron base plate mounted
upon the base block, and having an interior diameter equal to the inside diameter of
the pulley rim desired, and C¹ denotes a cap plate of a similar character; D denotes a
cast-iron "chill," preferably cast in one piece, and having its interior surface concaved
to a greater or lesser extent, corresponding to the degree of convexity of the belt
face of the pulley desired, and having a width corresponding with the width of the
face of the pulley rim to be cast.
Instead of being concaved the chill face may be straight, so that for wide straight
faced pullies two or more chills may be employed, one over the other.
In Figures 11 and 12 I shew the lower edge of a chill and the upper surface of
the circular base plate C. The chill is supported by the base plate, and to readily
adjust and secure them in position relatively to each other I provide the radial
recesses d on one, and the radial lugs d' on the other, which being correspondingly
located operate as dowels, and at the same time admit of the proper unity of the
chill and the plate when they are expanded by heat, as is liable in their use.
With the several parts of the mould thus constructed I proceed as follows:-The
sectional shell B is placed in proper position, with the prints duly adjusted. The
annular space between the central block a and the shell is then rammed with sand,
the detachable prints removed separately, and the sections of the shell separated
and removed, leaving the cylindrical core as at E, Figure 3. The circular base
plate C is then placed in position surrounding the core. The inner portion of its
upper surface constitutes a mold surface for one edge of the pulley rim. The
chill D is then put upon the base plate. The space between the inner surface of this
chill and the exterior surface of the core E determines the thickness of the pulley
rim. The cap plate C is then placed on top of the chill, which completes the
mould, the inner portion of the lower surface of said cap plate constituting the
molding surface of the other edge of the pulley rim. With the parts thus adjusted
the melted metal is poured through the gate e formed in the inner edge of tho cap
plate.
It is in some cases preferable to pour the metal through a vertical duct in the
centre of the core, thence into the mould by curved or straight lateral ducts to an
annular gate recessed into and surrounding the core at its base, and communicating
with the mould by a space equal to about half the thickness of the rim of the pulley
desired.
It will be seen that the chill will secure a smooth and proper finisli to the belt
surface of the rim, and that the sand core will permit uniform contraction, and
thereby secure a rim which is practically circular.
In Figure 3, at f, I shew a support for the circular plate C, whereby the chill
may be set at a proper height with relation to the prints at b.
When narrow faced pulleys are made, the lower series of print apertures b in the

page_text: shell B may sometimes be employed, in which case the plate C may be placed
directly upon the base block A. In general practice however the supports fof
various heights are required for securing accurate adjustment of the chill. The hubs
of these pullies may be cast in sand, although I prefer to cast them in vented iron
moulds, with a view to lessening their cost as far as possible. However they may
be cast they will be provided with arms, or in some cases with a web, for connection
with the rim.
In Figure 4 one of the improved pullies is shewn. The rim g is separately cast
solidly on a chill or other permanent mould, as already described, and the hub h
separately cast with the requisite number of arms, which are united to the rim in
each instance at i.
At Figure 5 I show a segment of a pulley illustrating one of the best connections
known by me for uniting the rim and arms. The prints being made in two parts,
as previously referred to, form on the inner side of the rin a projection having a
central dovetailed recess, and the adjacent end of the arm is provided with a similar
⚫recess. An adjustable hand mould, with or without clay joints, is made to enclose
the joint, and the melted iron or other metal is poured thereon, which when cooled
solidly unites the arm and rim. The form of this joint is such that the metal sur-
rounding it has freedom to contract without in any manner disturbing the relations
of the parts, but, on the contrary, said contraction is favourable to securing a desirable.
unity of the parts.
Figures 6, 7, and S represent other forms of joints which may be employed with
good results. Figure 8 illustrates clearly a wedge interposed between the pulley
arm and rim.
In some cases a web is desirable between hub and rim instead of arms. Pullies
of this class may readily be made in accordance with this Invention, as it will only
'involve a shell B provided with apertures for prints, which will provide an inward
annular projection from the rim with a serrated edge, and the casting of the hub
with a web having a similar edge, the two parts being united by a cast-metal joint,
as illustrated in Figure 9.
In
In some cases pullies with rims of great width require two series of arms.
casting such pullies solidly, as heretofore, the unequal contraction of the metal is a
serious obstacle to the attainment of good results.
It is obvious that the arins of the hub must correspond in the positions relatively
with the projections on the rim with which they are to be united.
Should two series of projections be cast with the rim, they would always be
regular and uniform in position with relation to each other, but two series of arms
cast solidly with a hub would seldom be uniform and regular in position with relation
to each other, owing to their liability to warp and twist in cooling.
In casting a hub with two series of arins solidly in a chill, the metal in that
portion of the hub which is between the series of arms would in contracting be
fractured on account of the unyielding character of the chill and the expansion
thereof by heat; therefore in making this class of pullies I cast a solid rim, as before
described, with the two series of projections, but cast the hub in two parts, each
with a complete series of arms; or, in other words, I cast two separate hubs, each
with its arms as for a pulley with one set of arms. These two hubs are placed side
by side, with their adjacent ends in contact, so that each series of arms will occupy
a proper position with relation to its proper series of projections on the rim to which
they are united, as before described. Inasmuch as the two hub sections are in close
contact with each other and are truly rimed, they can be readily and safely driven to
and fro on a shaft longitudinally; and being held to the shaft by separate set
screws, they will be united therewith in like manner as if the hub was solid.
For properly adjusting the hubs and rims I find that it can be quickly and eco-
nomically executed by use of a centering machine, which is illustrated at Figure 13
in central vertical section.
F denotes a circular table mounted on a vertical hollow spindle G, and arranged
to rotate thereon. The table is provided with four radial slides H, which are fitted

page_text: in radial slots, and are provided-with a downwardly projecting arm K, having a
tapped hole near its lower end parallel with its line of motion. The table has also
four hangers, as at 1, in which are bearings for screws I, which enter the tapped
holes in the arms K of slides H. The inner ends of each screw carries a bevel
pinion, as at m, which meshes with a large stationary bevel gear, as at n.
It will be seen that if the table F be rotated in one direction that all the slides
will be simultaneously moved outward, and vice versa.
At the inner end of each slide H is a longitudinally slotted adjustable finger o,
which is secured to the slide by a set screw p, thereby admitting of the nicest
adjustment with relation to a centre common to all of the slides.
A mandril is placed in the hollow spindle G, and a hub placed thereon already
properly rimed. A rim is then placed upon the table, which is then rotated, thereby
adjusting the rim to a truly concentric position with relation to the hub, and while
in that position the cast-metal joints are formed as near simultaneously as possible,.
and the pulley completed.
Instedd of having the table movable it may be stationary, and the gear n arranged
to rotate on the hollow spindle, so that a crank attached to one of the screws I will.
on being rotated actuate all the screws simultaneously.
While I prefer to use cast metal at the joints between rim and the hub or its
arms, I am aware that approximately economical results may be attained by uniting
the rim with the hub by means of bolts or rivets, and I do not therefore limit this
Invention to the use of cast metal at the joints.
It is to be distinctly understood that the improvements relate exclusively to belt
pullies, and that the prime object is economy in the manufacture of cast metal belt
pullies having in a practical sense a truly concentric rim and a well finished face.
I am aware that it is not new to make belt pullies with a wrought-iron rim and
cast metal hub and arm, but such pullies are devised for special or extraordinary
service, and are constructed, comparatively speaking, regardless of expense.
It is
'
In connection with the manufacture of wheels for cars and other vehicles, I am
well aware that such wheels have been made with a flanged or other rim cast with
its tread on a chill and its rear side on a yielding chilling core, and that such rims
have been united to a hub and arms, or their equivalents, in various ways.
well known however that the manufacture of car or other similar wheels, considered
in itself, is an art separate and distinct from that of manufacturing belt pullies.
The conditions involved in their manufacture are widely different, although both
are produced under the general art of casting metals. In the car wheel the heavy
rail flange renders the contraction of the cooling metal comparatively uniform.
A. car wheel constructed with a separate solid flange and separate hub and arms,
or their equivalents, is more expensive than the solidly cast wheel, and the object of
this more costly divisional construction is to render it possible to replace a worn out
rim with a new one without disturbing the hub and axle. The casting of the car
wheel flange rim on a chill secures a smooth surface, but it has been proven to be
advantageous to turn off the chilled iron to a certain depth, so that the originally
smooth surface is not available as an item in economy. With the belt pulley a belt
surface which is harder than ordinary cast iron has no additional value on account
of its hardness, the desired end being a smooth well finished surface. The car
wheels have heavy rail flanges and treads, involving the use of very considerable
bulk of metal, which is heavily distributed throughout the wheel, and therefore no
practical difficulty is experienced in attaining concentricity of the flange and tread
with the axis of the wheel; on the other hand, the rim of a belt pulley is extremely-
thin, usually as light as possible, while the hub and arms necessarily involve the
massing of more metal than is frequently required for the entire rim.
Incidental and in addition to that prime economy attained by this Invention.
through lessening the cost of moulding and obviating machine work on the belt face,
there are other minor points all contributing to the same end; for instance, I am.
enabled to use iron of full grade for the rims and half grade iron for the hubs and.
arms, which in itself is an economic item of very considerable importance. No

page_text: such possibility exists in car wheels, for none but the highest grades of iron can be
used in their manufacture.
Cast metal pullies as heretofore made with machine finished faces must of
necessity be composed of fine high grade iron throughout, while although I can use
two grades of iron, as before indicated, a thoroughly serviceable pulley can be made
by means of this Invention wholly of low grade iron, because no machine finishing
is necessary. It is true that low grade iron is not so strong as the high grade, but
it is to be remembered that in the solidly cast pulley much strength is requisite for
resisting the strain incident to contraction, while in this pulley no such strain
exists.
Now referring to the mould it will be obvious that its first cost will be equal to
or perhaps greater than the cost of a pattern as usually made, and the flask with
which it is used; but it will be seen that the cost of a multiplicity of patterns is
obviated. An ordinary regularly graded list of pulleys of upwards of two hundred
in number embraces but twenty-nine diameters, and therefore twenty-nine core
moulds, as employed by me, will be sufficient for producing rims for the entire list,
each core mould being suitable for the widest face, and of course any narrower face
of the same diameter; so also will twenty-nine pairs of the circular cap and base
plates serve for the entire list. And for making wide straight faced pulleys, two or
more narrow chills may be employed, one above the other, although for making
convex faced pullies a concaved chill will be requisite for each diameter and width
of pulley required.
If the hubs and arms be cast in a sand mould, the patterns therefor can readily be
made, so that additions to hub and arms may be at will provided, attached or
detached, for matching with rims of various widths of faces.
I am also enabled to cast a hub and arms on a chill, which while it adds in no
manner to their actual valuc, lessens the cost of casting as compared with the
common methods, and secures a desirable finish.
From this comparison of the manufacture of wheels for vehicles with the manu-
facture of belt pullies, it will be seen that this Invention is not based upon previous
results in the manufacture of such wheels, for that which rendered those wheels
more expensive renders the belt pulley less expensive; also, that the desirable capa-
cities in the car wheel, for instance, of admitting the replacement of an old flange
with a new one has no value in the belt pulley; also, although even if a hardened
chilled surface on the car wheel flange did possess value (which is not the case), a
similar surface on the belt pulley has no value by reason of its hardness.
Incidental to this Invention it will be seen that thereby practically perfect belt
pullies may be made with but little outlay for tools other than the moulds, which in
cost will seldom if ever exceed cost of patterns, as heretofore required in the regular
manufacture of pullies extensively conducted. For fitting my hubs a rimer is only
requisite, and key slotting or the set screw and its threaded seat in the hub involve
the use of simple mechanisms and the employment of low priced labor. The
centering machine is readily adapted to pullies of various diameters. None of the
usually employed face finishing tools are requsite, and the manufacture of pullies is
greatly simplified.
Practical operations have demonstrated that pullies can be made in accordance
with this Invention, and in every essential particular fully meeting the existing
requirements of the trade, at a cost of from 25 to 50 per cent. less than the cost of
pullies of the same size manufactured by the methods in vogue prior to this
Invention.
It is to be distinctly understood that I make no claim to the particular con-
struction or arrangement of the parts constituting the moulds, nor to any particular
form of joints between the solid central portion of the pulley and the separately cast
rim, for I am aware that moulds somewhat similar have been heretofore employed
in casting solid belt pullies and sectional car wheels, and that in the manufacture of
such car wheels a great variety of joints have been proposed at the junction of the
rim with the hub or arms projecting therefrom.

page_text: Having thus described this Invention, I claim as new and desire to secure by
Letters Patent,.—
First. The improvement in the manufacture of cast metal belt pullies which
consists in casting a solid rim in a mould having a yielding non-chilling core and a
permanent face surface, substantially as described, whereby a well finished belt face
and a practically circular rim is economically attained, as set forth.
Second. The improvement in the manufacture of cast metal belt pullies which
consists in separately casting the hub and the rim, the former with its arms or
their equivalents being cast in any suitable manner, and the latter cast in a mould
having a permanent face surface and a yielding non-chilling core, the two parts
being concentrically arranged and united together at the joints, substantially as
described, whereby smooth faced and practically concentric pullies may be econo-
mically produced, as set forth.
Third. A belt pulley having a solidly cast rim and a separately cast hub with
arms which are united to the rim, substantially as described.
In witness whereof, I, the said Peter Jensen, have hereunto set my hand and
seal, this Eighth day of November, in the year of our Lord One thousand
eight hundred and seventy-six.