Improvements in Roller Bearings for Sheaves or Pulleys.
Year: 1895

page_text: •
is Print is in accordance with the Original Specification as it stands after
Amendment (under Section 18 of the Patents, &c., Act, 1883), as allowed
by the decision of the Comptroller General of the 27th day of March 1897.
"
Date of Application, 19th Aug., 1895-Accepted, 21st Sept., 1895
COMPLETE SPECIFICATION (AMENDED):
[Communicated from abroad by FRANK CLEVELAND PITCHER, of Terrace.
Road, Medford, Middlesex County, Massachusetts, United States of
America.]
Improvements in Roller Bearings for Sheaves or Pulleys.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, do hereby
declare the nuture 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 relates to that class of roller bushings for sheaves and pulleys in
which a series of rollers are held in position around the shaft or spindle on which
the sheave rotates, by means of a casing secured to the sheave and forming the
core or central portion thereof. The casing is made as a separate piece from the
main body of the sheave, and is inserted therein and secured thereto by suitable
means, such as screws or rivets. As the casing has to sustain the load supported by
the pulley, it is important that it be of strong and durable construction, not liable to
be broken. It is at the same time important that the casing be constructed in such
manner that it can readily be opened to permit access to the rollers, for the purpose
of removing worn or broken ones, inserting new ones, and for similar purposes, as
they are removable and interchangeable.
My invention has for its object to provide a roller bushing comprising a casing and
a series of rolls held thereby in circular order, in which the casing shall have the
requisite strength and at the same time be capable of affording ready access to the
rollers. To this end, the invention consists in the improvements which I will now
proceed to describe and claim.
Of the accompanying drawings, forming a part of this Specification,-
Figure 1 represents a side elevation of a sheave provided with my improvements,
the construction being of the kind ordinarily used with wooden sheaves.
Figure 2 represents a section on line 2-2 of Figure 1.
Figure 3 represents a view of the inner side of the casing constructed as shown in
Figure 2, the cap applied to the casing being removed.
Figure 4 represents a view of the inner side of the cap or annular cover of the
casing constructed as shown in Figures 1 and 2.
Figure 5 represents a sectional view similar to Figure 2, but showing the preferred
construction when a metal sheave is employed.
The same letters of reference indicate the same parts in all the figures.

page_text: Referring for the present to Figures 1, 2, 3, and 4, a represents a cylindrical metal·
casing formed to be inserted in a chamber or opening prepared for its reception in a
wooden sheave' b, the casing a being open at one end across its entire internal
diameter and having at its opposite end an inwardly projecting flange al on the inner
edge of which is formed an annular rib a' formed to engage the trunnions on the
rollers hereinafter described, the-same-end of the casing having also an outwardly
projecting flange a³ which is of larger diameter than the casing and is formed to bear
against one side of the sheave and has orifices to receive attaching screws c by which
the casing may be secured to the sheave.
d represents an annular cap or cover, which-has an inwardly projecting, bead on
its inner edge and is of such diameter that its outer edge projects outwardly beyond
the periphery of the casing a, the cap d being preferably of about the same diameter
as the flange a of the casing. The outer portion of the cap d is provided with
screw-holes, said holes being preferably arranged to register with the holes in the
flange a, so that the can and flange can both he attached by the same screws c, as
shown in Figure 1. The cap d is attached wholly by the screws c, and when said
screws are removed, the cap is loosened and can be readily removed, from the casing
and from the sheave. The inner side of the cap d is recessed to form an abutment d
which bears on the outer surface of the casing a at the open end of the latter and.
prevents said casing from spreading at its open end under the pressure to which it is
subjected when in use.
e e represent rollers which are interposed between the inner surface of the casing a
and the shaft or spindle on which the sheave rotates, said rollers being provided at
their ends with trunnions e el which are engaged with the ribs a' and d, as shown in
Figure 2, the said ribs holding the rollers in place in the casing. Smaller rollers g
may be interposed between the rollers e, said 'rollers g bearing on the inner surface of
the casing a, as shown in Figures 1 and 3.
It will be seen that the cap d formed to cover and prevent the' spreading, of the
open end of the casing a and made readily separable 'therefrom and attached
wholly by screws outside of the periphery of the casing, not only enables the
casing to be made strong and durable, its continuity being unbroken - by. screw-
threads or other attaching devices, but also enables the roller-receiving space
to be readily uncovered to permit access to the rollers by the removal of the cap d.
Heretofore the casing of a roller bushing, of this class has been made of two
separable sections, one of which screws onto the other, the cylindrical part of the
casing. being divided and one part provided with an external and the other with an
internal screw-thread, this construction requiring the rotation of one part of the
casing in order to uncover the rollers. This construction is objectionable, because
it weakens the casing, rendering it liable to be enlarged by the- pressure exerted
upon it, and further because the screw-threads are liable to be caused to adhere to
each other by the spreading of the casing and by rust and corrosion, so that; the
separation of the parts of the casing is liable to be a matter of great difficulty, if not
an entire impossibility. It will be seen that by making the cap d with the abutment d
and without any direct attachment to the casing, and securing it only by screws which
can be readily removed and whose removal will not be materially impeded by rust-or
corrosion, I obviate the objections above mentioned.
In Figure 5. I show the preferred construction when a metallic sheave b' is used.
In this case a cylindrical casing:a is made without an outwardly projecting flange,
and has only an inwardly projecting flange a³ formed like the flange a and. provided
with an inwardly projecting rib a like the rib a². The casing is in..this case driven
or pressed tightly into the orifice formed for its reception in the sheave, and-is.held by
the tightness of its fit in said orifice, the casing having a slight external taper, so that
attaching screws are not required to screw the casing in place. The cap dis
constructed in all respects like the cap d above described, and is secured to the sheave
by screws c¹ passing through the holes in the outer portion of the cap, said holes being
outside of the periphery of the casing, so that the cap can be readily unfastened and
moved to permit access to the rollers.

page_text: The casing is made of brass or other equivalent inoxidizable metal or composition,
so that it not only presents an inoxidizable inner bearing or track to the rolls e,
preventing said rolls from rusting to the casing, but also presents an inoxidizable
outer surface to the iron or steel body of the sheave. The casing is therefore free
from liability of rusting to the body of the sheave, and can be readily forced out of
the sheave when it is so far worn as to require renewal. In other words, the casing
constitutes a rustless lining for the central cavity of the sheave, which is adapted to
be driven tightly to place and to be readily forced out when worn, so that the same
sheave can be used with several casings or linings, the durability of the sheave being
thus materially increased.
The rolls e e are preferably made of steel, and the smaller rolls 9 which are used
only to separate the rolls e from each other are made of bronze, so that they will not
rust and therefore will not adhere to the rolls e in case the surfaces of the latter
become rusted. The bronze rolls act to clean or wear off any accumulations of rust
that may form on the surfaces of the steel rolls, said bronze rolls being always free from
rust and in good working condition. It will be seen that the conjoint use of the steel
bearing-rolls to support the strain incidental to the use of the pulley or sheave, and
the bronze rolls to separate the steel rolls and keep them free from rust, increases the
effectiveness and durability of the bushing.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is :-
1. A sheave or pulley having a central cavity, a bushing or casing inserted in
said cavity and having at one end an integral inwardly, projecting flange forming
the fixed end of a roller-holding space within said casing, and an annular end-piece
or cap of larger diameter than the casing and attached outside the casing to the
pulley, said end-piece constituting the removable end of the roller-holding space
and having an abutment that surrounds and prevents the spreading of the open end
of the casing.
2. A sheave or pulley having a central cavity, a bushing or casing inserted in
said cavity and having suitable roller-confining ends or flanges one of which is
removable, a series of steel bearing-rolls located in said casing, and a series of
separating rolls of an inoxidizable metal such as bronze interposed between said
bearing-rolls.
3. A sheave or pulley comprising a suitable body having a central cavity, a
bushing or casing of inoxidizable metal removably inserted in said cavity and having
suitable roller-confining ends or flanges one of which is removable, a series of
bearing-rolls located in said casing and in rolling contact with the inoxidizable inner
surface thereof, and a series of separating rolls of an inoxidizable metal such as bronze
interposed between said bearing rolls.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.