Improvements in Wood Pulleys.
Year: 1897

page_text: Date of Application, 29th July, 1897-Accepted, 2nd Oct.,
1897
COMPLETE SPECIFICATION.
Improvements in Wood Pulleys.
I, FRANZ LUDWIG BARTHELMES, domiciled at 92 Niagara Street, in the City of
Toronto, in the County of York, in the Province of Ontario, Canada, Manufacturer,
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:-
My invention relates to improvements in wood pulleys.
The object being to produce a substantial wood pulley, having a rim formed
of thin layers of veneer, preferably knife cut veneer, hent circular and glued
together forming a rim which entirely overcomes the tendency of the fibre of
the wood to part on the greater circumference. Moreover this means of forming
a wood rim permits in the construction of the pulley of using either wood or iron
arms, also making the same in two halves divided diametrically producing a split
wood pulley, having the arms through which the diametrical division is made,
formed of thin layers of veneer.
In the accompanying drawings illustrating my invention, similar numbers of
reference refer to similar parts, throughout, and-
Fig. 1, a side elevation of my improved split wood pulley showing the con-
struction of the same.
Fig. 2, is a view in plan, of one half of the pulley, showing the construction of
the arms which form part of the hub.
Fig. 3, is a vertical sectional view on the line a to a, of Figure 2.
Fig. 4, is a side elevation of my improved pulley with iron arms.
Fig. 5, is a vertical longitudinal sectional view, showing construction of the
same.
Fig. 6, is a vertical transverse sectional view of the same.
Fig. 7, is an enlarged detail view of the hub of pulley shown in Figure 1, with
bushing inserted, and-
Fig. 8, is a perspective view of the bushing showing the construction of the
same.
The novelty of my improved pulley is the substituting of thin veneered wood
for the heavier formed rims of one or more pieces of steamed lumber, bent in a
circle or of many pieces jointed together.
In the drawings, 1, designates the rim of my improved pulley, which is com-
posed of thin layers of veneer, preferably knife cut lumber. The forming of
the rim in both kinds of pulleys those having wood arms and hub, being solely
of wood, and divided diametrically forming split pulleys, and those having iron
arms and hub, used for either loose or tight pulleys, preferably of small diameter,
are formed in the following way, the thin layers of veneer are glued and jointed
in a press which forms the several layers of veneer comprising the rim, into a
circle or semi-circle as the case may be. Thus forming the rim independent of
the arms, and the same will retain its form irrespective of the staying support
received from the arms, from the fact of the rim being formed of the said layers
of veneer, which practically reduces the strain in the rim to a minimum, there-
fore overcoming the tendency for the fibre of the wood to part on the greater
circumference.

page_text: The rim, 1, as shown in Fig. 1, is adapted to a split wood pulley, which consists
of two halves divided diametrically through the arms, 2, and 3, and secured
together by the usual bolts, 4. The arms, 2 and 3, are pairs, and formed of thin
layers of veneer, similar to the rim, with the centre portion forming the hub 5,
making a light but strong and durable hub and arms combined.
Upon the
arms 2 and 3 are additional braces 6, triangular in shape and matched with the
corner pieces 7, which increase the area of the ends of the arms, 2, and 3 to
which the rim 1, is dowelled or pinned as shown in Fig. 3, and also the area of
the surface for the bolts 4. Extending at right angles to the arms, 2, and 3,
are similar arms 8, with the exception of having the centre portion of one piece
in place of the veneer. Of the braces 6, there are two or more on each arm,
spaced on the arms, 2, 3, and 8, with reference to the width of the face of the
rim, 1, and have the portion 9, of the arms which falls between cut away, to
decrease the acting surface of the arms against the air.
On the rim, 1 and at the points of contact 10, are dowel-pins 11., The arms 2
and 3 which form the hub 5 have a slight depression in the centre from a straight
line with the ends, as shown in Figure 3, for the purpose of giving additional
compression on the contact portions 10, of the rim 1. In pulleys of three feet
in diameter and smaller, it does away with the necessity of the bolts near the
rim, as shown, the outer bolts may be used in addition to the above, on larger
pulleys and those doing heavy duty without materially altering the construction
of the pulley.
With pulley shown in Figure 1, I employ a bushing, 12 shown in Figure 8,
to accomodate the different sizes of shafts to which the same may be adapted, for
the construction of the hub 5 does not permit of boring the same to suit different
sizes of shafts.
The bushing 12, is formed by cutting on one side of suitable wood, longitudinal
V-shaped grooves or kerfs, 13, almost through to the other side, which permits
of bending the same into a circle.
To secure the separate pieces and prevent their parting, the outer surface has
rubber cloth or fabric, 14, cemented to the same.
The second part of my specification relates to the construction of a similar
pulley with the exception of having the arms formed of iron preferably cast iron.
The arms, 15, which terminate at one end in the hub 16, differ in only, one respect
to the ordinary arms of iron pulleys, by having the peripheral extensions capped
by an enlarged portion 17, forming a frustum shaped wedge, with the larger
side inserted into the rim as shown.
The rim in this case is not formed in one operation, but in the following way:-
Two semi-circular pieces 19, formed of two or more layers of veneer, according
to the size of the pulley to be constructed, are first brought to encircle the
extensions 17, of the arms, with the joints falling diametrically opposite in the
centre of the portions 17. Second, a thin band of veneer 20, is glued on the peri-
phery of the first portion 19, and having but one join which is midway between
the others. Third two similar bands of veneer 21, are glued on the interior of
the first portion 19, then spacing pieces 22, of the same material are glued to the
interior of the rim 19, between the bands 21, and the wedge portion 17, of the
arms 15, permanently securing the rim 18, to the arms 15, without the use of
bolts, screws or similar means for fastening the same.
".
The above described pulley is found most serviceable for pulleys of small
diameter, which permits of their being used as loose or tight pulleys, on light
counter shafts, for they are both light and strong.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is:-
Claim, 1. In a wood pulley divided diametrically each section of the rim formed
of several semi-circular bands of veneer olued one unon the other and having the

page_text: arms through which the diametrical division is made formed also of a number of
layers of veneer, substantially as shown and described.
Claim, 2. In a wood pulley divided diametrically each section of the rim having
the arms through which the diametrical division is made formed of a number
of layers of veneer in which is formed midway in their length the hub, which is
a portion of the same, substantially as shown and described.
Claim, 3. In a wood rim pulley, the rim formed of several circular and semi-
circular bands of veneer, glued one upon the other with the enlarged peripheral
extensions of the iron arms built within the same, substantially as shown and
described.
101 1
T11007
FRANZ LUDWIG BARTHELMES.