A New or Improved Method of and Apparatus for the Manufacture of Cast Metal Pulleys, Wheels, and other Circular Articles.
Year: 1895

page_text: Date of Application, 30th Dec., 1895-Accepted, 11th Apr., 1896
VUMIDELE DI BUITRATIO
A New or Improved Method of and Apparatus for the Manufacture
of Cast Metal Pulleys, Wheels, and other Circular Articles.
A communication from abroad by ABNER D. THOMAS, of Little Rock, Arkansas,
United States of America, Manufacturer.
1, JAMES GRIEVE LORRAIN, M.I.E.E., M.I. Mech. E., of Norfolk House, Norfolk
Street, Strand, London, W.C., in the County of Middlesex, Chartered Patent Agent,
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 consists partly of a process and partly of the apparatus for
carrying out the process, substantially as is hereinafter set forth and claimed.
In the drawings I show how my invention is carried into effect in the case of a
pulley. The way in which it may be carried into effect in the case of other
articles will be readily understood. In the said drawings
Figure 1 is a side elevation of a pulley capable of being made by means of this
invention:
Fig. 2 is a cross section on the line 2-2 of Fig. 1:
Fig. 3 is a plan of the base-plate which forms part of the apparatus in
question:
Fig. 4 is a cross section on the line 4-4 of Fig. 3:
Fig. 5 is a top view of one of the parts of the flask :
Fig. 6 is an inside elevation of the same :
Fig. 7 is an outside elevation of the same:
Fig. 8 is a plan of the. roller that is used in conjunction with the flask parts in
forming the mold:
Fig. 9 is a plan of the removable plate which forms the bottom of one of the
flasks:
Fig: 10 is an edge elevation of the same:
5
Fig. 11 is an elevation, from the inner side thereof, of the flask for forming the
inner mold-section:
Fig. 12 is a top view of the same :
Fig. 13 is an elevation of the same, looking in the direction of the arrow of
Fig. 12:1
Fig. 14 is a top view of the same containing the patterns for forming the hub
and spokes-chambers of the mold :
Fig 15 is a section on the line 15-15 of Fig. 14, the flask being partially filled
with sand:
.
Fig. 16 is an inside elevation of one half of the inner mold section, the cores
employed in forming the hubs being in position, and the mold sections resting upon
the bottom of the flask :
Fig. 17 is an inside elevation of one of the outer flask parts having the sand
molded therein :
Fig. 18 is a view showing in elevation, and from the inner side thereof, one half
of the entire mold, it being shown resting upon the base plate:
Fig. 19 is a top view of the mold supported upon the base-plate, the two halves
of the mold being separated from each other: and
Fig. 20 is a view similar to that of Fig. 19, but showing the mold sections
assembled and fastened to each other forming a complete mold.

page_text: The same letters of reference denote the same parts.
In carrying out the present invention I employ an apparatus consisting
principally of the following parts: Two similar-flask parts A and A', a roller B, a
flask C, and a base-plate D. The flask-parts are for forming and holding that
wall of the mold against which the face of the rim of the pulley, or corresponding
part of another article, is produced. The thickness of the rim is also formed in
that part of the mold which is held in the flask-parts. The flask C is for forming
that part of the mold in which the spokes and hub, or that portion of the casting
which is within the rim is made. It is also for forming that part of the mold
against which the inner side of the pulley rim is cast. The base-plate not only
serves to sustain the mold during the casting operation but also to facilitate the
assembling and the relative adjustment of the mold-sections. The roller is used in
conjunction with the flask-parts. Certain portions of the outer flask-parts and of
the flask C are concentrically made, and the centre of such portions is the centre
of the casting made therein, and this is the leading feature of the apparatus under
consideration. While more and larger surfaces of the flask-parts can thus be
constructed, I employ, in such flask part two surfaces only, namely the flanges a, a,
which are respectively at or near the ends of the flask parts. The inner edge a²,
of each of said flanges is curved circularly, the centre of said curves being as
stated an axis passing transversely through the centre of the ultimate casting, and
the curves being in the plane of the face of the rim of the casting. Between the
flanges the flask part is hollowed out suitably, and substantially as shown, to form
a receptacle a³, for the sand of that part of the mold. The shell, at, of the flask
part is preferably circular, although not necessarily so, as it might be otherwise
shaped without departing from the principle of the invention. It is suitably
perforated as at a³ to provide for venting the mold. Each flask part has
flanges a, a', to provide for uniting the flask parts in completing the mold.
A portion of the mold is formed in the flask parts. For this purpose the roller B
is brought into requisition. The roller has portions; b and b', which, in the use of
the roller, ride upon the flanges a, a¹, respectively of the flask-part, and 62, 63, are
guide flanges spaced just far enough apart to come upon the outer side respectively
of the flanges a, a¹. The roller is for pressing the sand in the flask-part properly
into shape to form the outer portion of the mold. So far as forming the face of
the rim of the pulley or other casting is concerned the roller throughout its length
between the guide flanges may be of uniform diameter; that is, it may have the
same diameter as that of the portions b, 6. But as I prefer to form the thickness
of the pulley-rim in that part of the mold which is contained in the flask part
I provide the roller with bands or band-like projections; 6, 6, which in width,
contour and thickness correspond to the width, contour and thickness of the
intended rim of the casting, and accordingly after the roller has been rolled
forward and backward upon the flask-part flanges a, a', recesses e, el, are formed in
the sand, substantially as shown in Fig. 17. At the points 6, 67, 68, the roller is
of uniform diameter with the portions b, 6', to enable walls, e², e³, e³, of sand to be
formed in the mold at each side of the recesses e, e', substantially as shown in
Fig. 17. When the flask parts are semi-circular two of them suffice to form the
flask. If they are less than semicircular obviously more than two flask-parts will
be required.
As thus far described provision has been made whereby the face and thickness of
the rim-portion of the casting can be produced. The mold for that part of the
casting which is within the rim, including the wall for the inner. side of the pulley
rim is obtained by means of the flask C. This last named part has the inner
side, c, of its shell c¹ curved to conform to the curvature of the inner surface of
the rim-portion of the casting. The other principal parts of the flask C are the
plate, which, when applied to the shell c', encloses a semi-cylindrical space, and
a semi-circular plate, c, which forms the bottom of the flask C. The plate c² has
a print in the form of a semi-circular rib c (see Figure 12) extending vertically
and centrally thereon, and the plate c³ has a rib c extending transversely and

page_text: centrally thereon, all substantially as shown. The flask C is designed for forming
one half of the described central portion of the mold, and to form the other or
remaining portion a similar flask C is employed, or after making one half of said
central portion the other half thereof can be made in the same flask C providing an
additional bottom plate is used. To form the mold of the portion of such central
part which is within the rim the plate c³ is inserted in the shell c', to rest upon a
ledge thereon, and the plate having a suitable sectional pattern F provided
(when a pulley is to be made) with separate hub-portions f, and core f' of suitable
material, and separate spoke-portions f¹, properly centered and arranged, is by
means of suitable fastenings e, attached to the shell el, all substantially as shown,
and the sand is rammed into the flask C as indicated in Fig. 15. The plate c³
and the attached print are then removed and the patterns and are separately
withdrawn from the sand. The described half of the central portion of the mold,
resting upon the bottom plate, is then removed from the shell c'. The other half
of the central portion of the mold is similarly made.
The entire mold in this manner has now been produced, but in four separate
portions, namely the two portions which have been formed, and which now remain
held in the two flask-parts respectively, and the two portions which have been
made in the flask or flasks C, and which now each rest upon a bottom plate. It
remains to assemble these parts and properly unite then to complete the mold, and
for this purpose the base-plate is brought into requisition. Said plate (see
Figures 3, 4, 19, and 20) has flanges d, d', extending longitudinally upon the plate
and spaced far enough apart from each other to receive between them and sustain
the two flask-parts. The base-plate also has a central rib d² grooved at d³, and
two ribs d, d, arranged respectively at the sides of said central rib, and said three
last mentioned ribs serving to sustain the bottom plates as shown. The rib upon
the underside of the bottom plates engages in the groove in the central rib. The
two halves of the central section of the mold with cores f2f2 in position are
properly brought face to face and in contact with each other, the bottom plates of
the flask C being slipped upon the base-plate, and guided by the bottom-plate ribs
engaging in the grooved rib as described, until the mold sections are in contact.
The two flask-parts containing their respective portions of the mold are then
slipped upon the base plate until they meet as in Fig. 20. When the parts are
thus assembled the bottom plates of the flask C meet the flanges a¹ of the two
outer flask-parts, and the sand of the central portion of the mold meets the sand of
the flask-portion of the mold at the points 2, e², e³, and also meets the upper
flanges a, all as indicated in Fig. 18. The mold is now complete and the casting
is poured in the ordinary manner.
As illustrated in the drawings provision is made for casting two pulleys at once.
The apparatus can be designed for casting one or more pulleys as preferred. The
various projections 6, 6, upon the roller are in the form of bands which are loose
upon a shaft, the object being to enable the different parts of the roller to rotate
independently of each other; that is, the roller in the present instance is composed
of a shaft and the bands 4, 5, the shaft is the part which rolls upon the
flanges a, a', and the bands as stated are the portions which form the recesses in
the mold; each of these parts can rotate independently of each other as the roller
is rolled over the flanges a, a', and the sand, and thus the work of molding the
sand can be readily and properly performed.
The various described parts of the present apparatus, to obtain the best results,
should be accurately made. The flask-parts should be accurately constructed and
fitted to each other to enable the flanges a, a', to jointly form perfect circles,
whose centre is the centre of the casting to be made, and the flask-parts and the
coacting portion of the flask C should be accurately relatively constructed to
enable the space in which the rim of the pulley is molded to be of uniformn
thickness, or otherwise constructed to suit the special shape of the casting being'
made, and the base-plate should have its side flanges and its central groove, or
whatever equivalent feature is substituted for such central grooves, properly

page_text: relatively arranged, substantially as shown, to enable the flask-portions and the
central portions of the mold to be assembled concentrically.
The pulley is thus enabled to be cast in a mold whose centre and circular
portions are inechanically true, and with reasonable care in molding the mold and
the pulley should be and are exactly made. The roller when used as described
solidifies the surface portion of the sand where the face of the pulley is molded,
but the sand farther back in the flask-part is not so much compacted, and thus a
better outlet is provided for venting the gases.
There is much less liability in the present pulley-molding apparatus that there
will be any unequal expansion or giving away of the mold before the molten metal,
and hence there is more certainty that the pulley rim will be of uniform thickness.
throughout and the pulley thereby better balanced. Another advantage accruing
from the invention is that any desired crown, or any special shape, can be imparted
to the pulley rim. By suitably shaping the band or bands upon the roller any
desired form, in the respects mentioned, can be produced in the pulley or other
casting to be made. A grooved pulley, for instance as used for transmitting power
by means of ropes, can be as easily made as a smooth pulley. It will be noted
that the flanges a, a', upon the flask-parts are the means for gauging the impression
produced in the sand in the flask-parts. And while I prefer to employ a roller
such as shown, and while the desired impression in the sand of the flask-part is
produced more satisfactorily by rolling the roller upon the flask-flanges a, a,
desire not in all cases to be restricted thereto, as other means may be employed
in connection with said flanges to produce the desired impression in the sand.
The flask-part or parts may be used for making split pulleys. After molding
the flask-part and a half central-mold portion in the manner described said part
and portion may be arranged concentrically, and the space between them, by any
suitable means not shown, be closed to form a complete mold in which a half of a
split pulley may be cast. Any needed lugs to be used in uniting the parts of the
pulley may be specially provided for in shaping the mold.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In an apparatus for making pulleys, wheels and other cast-circular articles,
the combination of the flask-parts and the core-box, said parts and box jointly
having concentric portions whose centre coincides with that of the casting made
therein.
2. The hereindescribed flask-part having the curved flanges a, a³, and the sand
receptacles a³, substantially as described.
3. The combination of the flask-parts each having the curved flanges a, a¹, the
receptacle a³, and the flanges a, a, substantially as described.
4. The combination of the flask-parts having the curved flanges, and the
core-box, said core-box having the curved inner face, substantially as described.
5. The combination of the flask-part and the base-plate, said base-plate having
the guide-flanges, substantially as described.
6. The combination of the base-plate, flanged at its sides and grooved centrally,
with the flask-parts and the plates c², substantially as described.
7. The combination of the base-plate grooved centrally as described and the
plates c³, substantially as described.
8. The combination of the core-box shell, the bottom plate and the plate c²,
having a print, said parts being separable from each other, substantially as
described.
9. The combination of the flask-part having the curved flanges a, a¹, and the
roller B, substantially as described.
10. In the hereindescribed apparatus for making pulleys, wheels and other
cast-circular articles, the core-box having the centrally arranged prints as set
forth.

page_text: 11. The combination of the flask-parts having the curved flanges and the sand.
receptacle and the roller having a band or bands loose thereon, substantially as
described.
12. The hereindescribed mode of manufacturing pulleys, wheels and other cast-
circular articles the same consisting in forming the mold for the outer face of the
rim of the pulley, etc. in an outer flask, and the inner portion of said rim of
pulley, etc. in a core, and then arranging said outer flask and said inner core
concentrically, and then casting the same.
13. The combination of the flask-portion of the mold and the core-portion of the
mold, said portions being arranged concentrically and inclosing between them the
chamber for forming the rim-portion of the pulley, etc. substantially as described.
14. The herein described process of forming by means of a roller a cavity in
which to cast the rim of a circular article, in a sand mold, substantially as
described.
15. The herein described apparatus for making molds for pulleys and other cast
circular articles, consisting in combination of the outer flask-parts, the inner flask-
part, the support for the central mold sections, and the base-plate, said flask-parts
and support being adapted to be assembled concentrically upon the base-plate.
16. The combination of the base-plate flanged at its sides and grooved centrally
with the outer flask-parts and the support for the central portion of the mold
provided with a lug.
Dated this 27th day of December 1895.
J. G. LORRAIN,
Chartered Patent Agent.