Improvement in Thrust Blocks for Shafts.
Year: 1892

page_text: Date of Application, 24th Nov., 1892
Complete Specification Left, 10th Mar., 1893-Accepted, 15th Apr., 1893
PROVISIONAL SPECIFICATION.
Improvement in Thrust Blocks for Shafts.
We, JOHN ANDERSON PAUL and WILLIAM CLARK PAUL, both of Jersey
City, Hudson County, New Jersey, United States of America, Engineers, do
hereby declare the nature of this invention to be as follows:-
This invention relates to a thrust block designed for preventing the longitudinal
pressure exerted upon the shaft of a screw propeller by the water from being
transmitted to the crank shaft. Within the journal box turns a shaft which carries
at one end the propeller and is driven at the other end by a crank as usual.
Centrally within the box, the shaft is provided with a collar having an annular
groove on each of its sides. Opposite to the collar, the box contains a pair of
sectional grooved disks. Within the grooves there are contained a series of friction
balls. The disks are divided on their longitudinal diameter so that they can be
properly placed in position above and below the shaft. The lower section of each
disk is seated upon a curved shoulder of the box. The upper section is held down
upon the lower section by a cover secured to the box by screws and having a central
downwardly depending lug entering a corresponding slot in the box.
To properly hold the disks in position and permit lateral adjustment, set screws
are tapped through the box and bear against one set of the sectional disks.
Dated this 24th day of November 1892.
ALLISON BROS.,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvement in Thrust Blocks for Shafts.
We, JOHN ANDERSON PAUL and WILLIAM CLARK PAUL, both of Jersey
City, Hudson County, New Jersey, United States of America, 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 :---
This invention relates to a thrust block designed for preventing the longitudinal-
pressure exerted upon the shaft of a screw propeller by the water, from being
transmitted to the crank shaft. Our improved thrust block is made in the form of
a ball bearing which greatly reduces the friction and consequently economizes
power to a considerable extent.
In the accompanying drawing:
Fig. 1 is a longitudinal section of our improved thrust block.
Fig. 2 a top view thereof with one of the covers removed and with the balls
omitted.
Fig. 3 a cross section on line x, x, Fig. 1 & Fig. 4 a cross section on line y, y,
Fig. 1.
The letter a, represents a base piece the ends of which are slotted centrally and
provided with a semi-circular bearing surface at the base of the slot, for the
reception of shaft b. This shaft carries at one end the propeller and is at the
other end driven by the crank shaft, as usual. Centrally within the base piece a,
the shaft b, is provided with a collar b¹, having an annular groove 3, in each of its
sides. Opposite to the collar b', the base piece a, contains a pair of sectional disks
or bearings c, provided with grooves c¹, corresponding to and facing the grooves 6².
Within the grooves b³, c', there is contained a series of balls d, which when the
[Price 8d 1

page_text: shaft b, revolves, will revolve with it, as will be readily understood. The disks c,
are divided on their horizontal diameters (Fig. 3) so that they can be properly
placed in position, above and below the shaft. The lower section of each disk is
seated upon a curved shoulder a¹, of base piece a. The upper section of each disk
is held down upon the lower section by a cover e, secured to the base piece by
screws e. Each of the covers e, is made shaped, being provided with a down-
wardly projecting central lug e, that fits into the slot of the end pieces. The
lower edge of lug e², is provided with a semi-circular bearing to embrace the upper
half of the shaft. Thus while the horizontal section of the cover holds down the
disk, the vertical section holds down the shaft to prevent unequal pressure upon
the balls in case of unequal strain upon the shaft.
To permit lateral adjustment of the disks c, screws f, are tapped through one
side of the base piece, which bear against one set of the sectional disks.
In use, the longitudinal pressure upon the shaft in either direction (going ahead
or astern) will be transmitted to the balls d, that will bear against the front or rear
disk c.
But as the balls revolve with the shaft, the friction is by far less than
with thrust blocks in which the collar on the shaft frictions directly against
the disk.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :
The combination of the slotted base piece, a shaft, a grooved collar thereon,
grooved disks, one adjustable relatively to the collar, balls in the grooves, an
L-shaped cover projecting over each disk, and adjusting means bearing against one
of the disks, substantially as specified.
Dated this 10th day of March 1893.
ALLISON BROS.,
Agents for the Applicants.