An Improved Thrust Blook.
Year: 1894

page_text: Date of Application, 24th Jan., 1894
Complete Specification Left, 22nd Oct., 1894-Accepted, 29th Dec., 1894
PROVISIONAL SPECIFICATION.
An Improved Thrust Blook.
We, JOHN GEORGE ALDER, and THOMAS MARK ALDER, both of Red
House, Cleadon, Sunderland, in the County of Durham, Engineers, do hereby
declare the nature of this invention to be as follows:-
Our invention relates to thrust blocks for marine, propeller, shafts, or other
purposes. It consists of a cast iron or cast steel base, with cast steel thrust rings
bolted to it. The thrust rings are made in halves and are firmly bolted together
with distance pieces between them at the top and at the bottom. On the thrust
face of each ring, we cut a groove, or grooves, concentric with the shaft; and in
each groove we place a number of hardened steel balls, which, when resting on
the bottom of the groove, project a little beyond the face of each ring. The
shaft is made with thrust collars in the usual way. Upon the thrust face of each
collar, we pin a hardened steel face. When the shaft is in position the collars
prevent the balls from falling out of the grooves. The balls are placed in the
grooves, one by one after the shaft is placed in position, through radial grooves
or holes made at or near the tops of the thrust rings. These grooves or holes are
afterwards closed by filling pieces.
When the shaft is working the collars press upon the balls and the balls then
roll around the grooves.
The thrust is thus taken upon a rolling surface instead of upon a fixed surface
as is usual the case..
Dated this 23rd day of Janu 1801
J. G. ALDER,
T. M. ALDER,
Applicants...
We, JOHN GEORGE ALDER, and THOMAS MARK ALDER, both of Red
House, Cleadon, Sunderland in the County of Durham, Engineers. 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:—
purposes.
Our invention relates to thrust blocks for marine propeller shafts or other´
It consists of a base preferably of cast iron or cast steel adapted to
carry cast steel thrust rings. The thrust rings are made in halves and are firmly
bolted together and they are fitted into the base in such a way that they are spaced
each from the next by two distance pieces placed respectively at opposite ends of a
diameter through the axis of the shaft, each ring being loosely bolted to or
carried by recesses in the base, or otherwise attached to the base so that it is
free to move in the plane of its surface and also to oscillate about the diameter
supported by the distance pieces, whereby. it can accurately adjust itself
centrally about the shaft and afford an even.pressure around its bearing
surface.
"

page_text: t
On the thrust face of each ring we cut a groove or grooves concentric with the
shaft and in each groove we place a number of hardened steel balls which when
within the groove, project beyond the face of each ring.
The shaft is made with thrust collars in the usual way, or these collars may be
parrower or the thrust rings may be further apart in order that we may pin a
hardened steel face to bear against the aforesaid balls, said face being either flat
or provided with a counter groove.
As an illustration of the method of carrying this invention into practice, we
have illustrated in the annexed drawings a thrust block with four rings.
Fig. 1'is a side elevation and Fig. 2 an end elevation of the thrust block.
Fig. 3 is an end elevation of one of the thrust rings.
Fig. 4 is a side elevation and Fig. 5 an end elevation of a modification in
the construction of the thrust block.
A is the shaft, B are the thrust collars solid with the shaft, having, if necessary,
hardened steel faces pinned to them on the wearing sides as will be readily
understood without need of illustration. C are the thrust rings in two pieces
firmly bolted together. E are the hardened steel balls which work in a groove
or grooves F. There may be more than one groove in each wearing surface if
required, provided such grooves are concentric. The groove F may be in the
thrust rings C only and a flat face on collar B, or counterpart grooves may be
made in rings C and collars B as shown.
The diameter of the balls and the depth of the grooves are so proportioned to
each other that the faces of the collars and rings can never come into contact.
K is a hole or groove by which the balls are put into groove F: when groove F
is full the hole or groove K can be plugged up.
There is no limit to the number of collars B or rings C. On the drawing,
two of the collars B are shown as bearing on one side only, but if required they
may be arranged to bear on both sides as shown on the right hand collar in
Fig. 1.
represents the base which may be in two lateral parts bolted together. The
upper side edges of the base J extend upward to above the horizontal plane of the
axis of the shaft A and are provided with recesses H, preferably rectangular.
These recesses serve to receive projecting ears G, G, of which each thrust ring
carries two,. projecting from it diametrically on opposite sides as shown in
Fig. 3.
The recesses H permit of a limited amount of vertical self adjustment for each
ring C, that is to say adjustment in the plane of the ring permitting it to always
exactly centre itself with the shaft, and they also permit of a slight amount of
oscillatory adjustment whereby pressure may be the better equalized all around
the bearing surface. The solid standing parts H₁ between the recesses H in
the walls of base J, serve as distance pieces for spacing the thrust rings.
The base J may be made in halves of cast iron or cast steel as shown, or it may
be made in one piece. In the latter case the walls of the base are set a little
further apart and the distance pieces made to project inwardly beyond the walls of
the base for a purpose to be hereinafter stated.
When it becomes necessary to remove the balls from the grooves, the plugs K
are taken out and the rings are then turned upon the shaft for a half revolution
when the balls fall out by gravitation.
In order that the rings may be turned round for this purpose without raising
the shaft, the two parts of the base, when the base is made in halves are separated
sufficiently to allow the ears G, G, upon the rings to clear the sides of the base,
"when the rings are being turned round.
When the base is made in one piece, we set the walls of the base a little
further from the centre line as shown in Figs. 4 and 5 and make the ears G, G,
upon the rings sufficiently short to clear the walls of the base when the rings are
turned round upon the shaft. In this case we make socket pieces G¹ longer than
the ears G, G, so that they project over the walls of the base, and so prevent the

page_text: rings from turning round with the shaft when it is revolving. Then, by removing
these socket pieces or bearing blocks G₁ the rings can be readily inverted without
raising the shaft.
By the mode of construction above detailed the thrust rings are perfectly self
adjusting to every movement of the shaft. When the shaft settles, through wear
of the bearing brasses, the rings follow it, thus keeping the grooves in the thrust
rings always concentric with the shaft, and so preventing any jamming of the
balls. If the shaft settles more at one end than at the other, the oscillating
movement of the rings allows them to adapt themselves to the new position of
the shaft. If from imperfect fitting, or from any other cause there is any lateral
displacement of the axis of the shaft, the rings have sufficient play to follow such
displacement.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, we declare that what we
claim is ;-
1. A thrust block having a base in which are supported thrust rings spaced by
distance pieces in the manner and with the result set forth, and provided with
annular grooves in their thrust faces to receive balls or the like to afford rolling
contact for the collars of a marine propeller shaft or other shaft.
2. The construction of thrust block comprising base J, rings C with grooves F
adapted to receive shaft A with collars B and balls E, and to adjust itself thereto,
substantially as set forth.
R. HADDAN,
¡18, Buckingham Street, Strand, London, W.C.
Agent for the Applicants.