Improvements in Lifting Jacks or Apparatus for Raising and Lowering.
Year: 1892

page_text: Date of Application, 13th May, 1892
Complete Specification Left, 1st Feb., 1893-Accepted. 18th Mar., 1893-
PROVISIONAL SPECIFICATION.
Improvements in Lifting Jacks or Apparatus for Raising and
Lowering.
A communication from abroad by ARTHUR OSMORE NORTON, of 45, Olive
Street, Boston, in the State of Massachusetts, United States of America,
Manufacturer.
I, PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane in the County
of Middlesex, Fellow of the Chartered Institute of Patent Agents, do hereby
declare the nature of this invention to be as follows:-
This invention relates to lifting jacks or apparatus for raising and lowering, and
particularly to the jack described in Specification to Letters Patent No. 3837
of 1888, the object being to simplify the construction of such jack.
In the jack as at present constructed I employ a standard having an internally
screwed head or nut in which works the lifting screw, said screw having on its
upper portion a bevel gear, and above this a fixed and a loose disc, between which
are a number of anti-friction balls or rollers preferably separated by concentric
rings. The upper or loose disc may be free or may revolve around a turned down
portion of the standard, in which case a few anti-friction balls are placed between
same and said standard. This disc supports the outer casing or sleeve which is
free to revolve around the standard, said sleeve being provided with a lifting foot
or being adapted to carry a lifting book or the like. The casing has an opening
left therein through which a second smaller bevel gear adapted to engage with the
first may readily pass. The shaft of this gear is carried by a cap or plate which
closes the aperture of the casing and is adjustable by means of a screw or screws so
that the amount of engagement of the two gears may be regulated. When this is
secured the plate is fastened in the desired position to the casing by bolts or other-
wise. The shaft of the second bevel gear (the function of which is to turn the first
and so through the screwed standard to raise the casing) is operated by a ratchet
wheel with which engages a double or anchor shaped pawl.
This pawl is provided with a spring controlled pin, said pin engaging with a
shoulder or a block in which the pawl is pivoted. The block is provided with a
socket for a handle so that the pawl may be operated to move the ratchet, the
construction of said pawl enabling either end to be thrown into engagement with
the ratchet so that the same reciprocating motion of the handle will operate the
ratchet to raise or lower the casing. As the casing can readily turn on the standard
it enables the handle to be brought into a convenient position for use.
The casing
is further provided with a spring catch which presses against the standard and
engages with a groove.turned on the upper part of same when the casing has been
raised sufficiently high for safety. The casing is preferably provided with a screwed
head which is readily removable for inspection of the ball bearing, and means may
also be provided for sustaining the main screw against lateral displacement.
In another construction of jack the gears may be contained in a base or casing,
the screw in its revolution forcing upward the sliding sleeve which is carried by
said base.
Dated this 13th day of May 1892.
PHILIP M. JUSTICE.

page_text: COMPLETE SPECIFICATION.
Improvements in Lifting Jacks or Apparatus for Raising and
Lowering.
A communication from abroad by ARTHUR OSMORE NORTON, of 45, Olive
Street, Boston, in the State of Massachusetts, United States of America,
Manufacturer.
I, PHILIP MIDDLETON JUSTICE of 55 and 56, Chancery Lane in the County
of Middlesex, Fellow of the Chartered Institute of Patent Agents, 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 lifting jacks or apparatus for raising and lowering and
particularly to the jack described in Specification to Letters Patent No. 3837
of 1888, the object being to simplify the construction of such jack.
To clearly explain the invention reference is made to the accompanying drawings
in which
Fig. 1. is an elevation partly in section of a screw jack provided with the present
improvements:
Fig. 2. is a plan of the upper part of the jack with the cap and other parts
removed to show the ball bearings.
Fig. 3. is a face view of the ratchet for operating the screw.
Fig. 4. is a face view of the spring stop catch.
Fig. 5. is a face view of the adjustable plate hereafter described and
Fig. 6. is an elevation partly in section of another form of screw jack.
The jack shown in Fig. 1. consists of a standard a having an internally screwed
head or nut such nut being formed preferably of a removeable ring as shown, the
ring being retained in place by small set screws b'. In this nut works the lifting
screw c said screw carrying at its upper end a bevel wheel d above which is an
annular disce on which rest balls e', the balls being preferably arranged in rows
which are separated from each other by concentric rings e². Around the outer ring
of balls is a retaining ring e and above the balls is a second annular disc f. The
top of the screw projects through this disc as shown and between same and the
disc may be arranged if desired a row of balls to relieve the side strain at
the head of the screw; but these may be omitted and the head of the screw be
made simply to snugly fit the opening in the disc. The disc f bears in turn against
a cap g which is screwed or otherwise removeably attached to the casing or sliding
sleeve which is free to revolve around the standard a so that the operating handle
hereafter described may be brought into a convenient position for use.
The sliding
sleeve may also be provided with a projecting foot at the base to lift objects close
to the ground or may carry other means for the same purpose such as a hook or the
like. The cap g is somewhat larger than the sleeve for the purpose of carrying
gears of suitable size.
The cap g is formed with an opening through which a second bevel wheel i may
readily pass so as to be brought into engagement with the gear d. The shaft of
the gear i is carried by the bearing formed in a plate which closes the aperture of
the casing and is adjustable by means of a screw k, Figs. 1 and 5, which passes.
through a ring bearing against the lower edge of the plate j. The latter when
its height has been adjusted by the screw is secured in place by the nuts the bolts
of which pass-through elongated or slotted openings in the plate j. In this way
the gears may be nicely and easily adjusted and kept in their proper position. The
shaft has a ratchet wheel m affixed thereto and with this engages a double or
anchor shaped pawl m¹ hung in ears forming part of a socket n which is itself
revolubly hung on the shaft. The socket n has a projection n' against which

page_text: bears a pin o which works in a socket in the pawl m' and against a spring in the
interior of said socket. The socket n is adapted to receive a bar or handle for
operating purposes.
When the pawl m' is in the position shown in Fig. 3 with its upper tooth
engaging the ratchet it will be seen that a reciprocating motion given to the socket n
will cause the ratchet to be operated in the direction of the arrow as the pin o
which rests in a slightly curved recess in the projection n² retains the pawl in this
position, but if the lower portion of the pawl is pressed in so that the pin o rests in
the second curved recess shown on said projection the lower tooth of the pawl will
come into engagement with the ratchet so that by the same motion of the socket
the ratchet wheel will be operated in the reverse direction. In this way the lifting
screw c may be conveniently raised or lowered without altering the position of the
operating handle. The casing or sliding sleeve his provided with a stop catch
pivoted in ears p'p', Fig. 4, the tooth of said catch being kept normally pressed
against the standard a by a spring q.. As the casing or sleeve rises up the standard
by the action of the screw working in the nut 6 the point of said catch will bear
against the standard until it reaches the circular bevelled groover around the head
of the standard which will catch same when the sleeve has been raised sufficiently
high for safety. When the sleeve is being brought down the point of the catch
will slip out of the groove over the bevelled edge without the necessity of releasing
the catch in any way by hand.
P
The jack shown in Fig. 5 has the position of the gears reversed as they are in
this instance placed in the casing or base h¹ which is enlarged for this purpose, such
casing terminating in a sleeve / squared if desired in which slides the standard
similarly squared which in this case is now the moveable portion, the casing which
was in the other form of jack moveable being now stationary. The screw c works
in the nut in the standard a and the base or lower part of the casing h¹ is provided
with the plate to allow of the introduction of the gear i. In the jack shown this
plate is not provided with the adjusting devices, as it only serves the purpose of
enabling the gears to be readily got at but it may be so provided if desired. The
screw has its bearing in the base or enlarged portion and such bearing may be
similar to that shown in Fig. 1 or be a plain bearing as shown. It will be seen
that the jack in question is practically the jack shown in Fig. 1, operating in the
reverse position.
The arrangement of the sliding sleeve standard and screw nut described enable
the operating screw to be easily guided and supported, it also renders the use of a
smaller screw possible than is at present employed as said screw is so supported
that it has only an end thrust to bear, the sleeve and standard taking the bending
or side strain and also bringing the friction on the screw nearer the centre than is
possible with a larger screw, thus giving a better application of the power.
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. In a lifting jack the combination with the standard and screw and means for
revolving said screw of a casing or sleeve provided with a cap having a bearing for
said screw composed of a disc and a train or trains of balls interposed between
said plate and the screw substantially as described.
2. In a lifting jack the combination with the standard and screw and means for
rotating said screw of the sleeve and its cap, discs ef a number of concentric rings
interposed between said discs and trains of balls arranged between said discs and
rings substantially as described.
3: In a lifting jack and in combination, the standard, screw, casing or sleeve, cap,
disc f and train of balls f¹, means for turning the screw disc e rings e and the train
of steel balls filling the annular spaces between the rings substantially as
described.
4. In a lifting jack and in combination the standard, screw, a nut in said standard

page_text: for carrying the screw, means for rotating the screw, a sleeve, an enlarged cap or
base attached to the sleeve and a suitable bearing for said screw in such cap or
base substantially as described.
5. In a lifting jack the combination with a standard, sleeve, gears and operating
screw of a plate and means for adjusting same substantially as described.
6. In a lifting jack and in combination a standard, a sleeve, a spring stop catch
attached to the sleeve and an annular bevelled groove in the standard substantially
as described.
7. The improved lifting jacks substantially as described and illustrated in the
drawings.
Dated the 31st der af Joner 1802
PHILIP M. JUSTICE.