Improvements in Hydraulic Lifts.
Year: 1890

page_text: Date of Application, 9th June, 1890
Complete Specification Left, 9th Mar., 1891-Accepted, 30th May, 1891
Improvements in Hydraulic Lifts.
I, OTTO KRELL, of St. Petersburg, in the Empire of Russia, Managing Director
of the St. Petersburg Metal Works, do hereby declare the nature of this invention
to be as follows:
The construction of hydraulic lifts adapted to be operated by direct action and
to be raised to considerable heights has hitherto required a stationary cylinder to
be sunk in the ground, which involved considerable expense besides being attended
by great technical difficulties. The plunger rod for instance owing to its very
great length comparatively to its thickness, has to withstand a powerful breaking or
bending strain; the consequence being that in order to render it capable of
sufficient resistance, it is necessary to proportion its size in a manner inconsistent
with what is required-in regard to diameter-for obtaining the most advantageous
liquid pressure.
In the directly acting hydraulic lift or elevator constructed according to the
present invention, these drawbacks are obviated by the employment of a differential
plunger, permanently suspended by its upper end, and yet adapted to force the
water, required for exercising the hydraulic pressure, upwardly.
A lift or elevator embodying these improvements is represented in the accom-
panying drawing, in which Figs. 1 and 2 are diagrammatic views of different
positions of the cage, while Fig. 3 is a plan of the whole arrangement.
The plunger of the motor or elevating cylinder is a differential plunger or piston
which is made smaller at the upper portion than at the lower part, and is per-
manently suspended by its upper end.
Upon this plunger slides the elevating or motor cylinder or pump provided with
a stuffing box at either end and supporting the cage O. The lower or thicker
portion of the piston rod assumes the shape of a tube, and it is through this portion
that the liquid, employed to create hydraulic pressure, is admitted from below into
the hollow piston rod; whence, through openings provided in the upper end of the
thicker portion it passes into the motor cylinder or pump.
Owing to such an arrangement the plunger is only submitted to a tension strain,
so that nothing prevents its diameter being such as is consistent with the most
advantageous utilization of the liquid pressure available; nor is it necessary to sink
the piston rod underground.
In the example illustrated in the drawing a special method of guiding the rod
and of adjusting its point of suspension is represented but any suitable means may
be adopted for these purposes if desired.
The cage may be guided in the form of clevator shown, by means of a slotted
tube concentrically surrounding the elevator cylinder or pump, and secured to tho
wall of the building by means of stays. The cage is provided, on diametrically
opposite points of its guiding column with slotted sliding cheeks. The neck rigidly
secured to the cage, and passing through the slot in the tube and surrounding the
cylinder or pump, by tightly adhering to the edges of the slot in the guiding
column or tube, prevents the cage from turning. At the upper end of the slotted
guiding tube an open attachment or length of the tube G (Figs. 1 and 2) is
provided through which access may be had to the upper stuffing box of the
cylinder or pump. Upon this piece G are erected the required number of tubes H
(Figs. 1 and 2) carrying at their upper ends the support K from which the
plunger rod is suspended.
Dated this Oth dor of Lune 1890
W. P. THOMPSON & BOULT.
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Hydraulic Lifts.
1, OTTO KRELL, of St. Petersburg in the Empire of Russia, Managing
Director of the St. Petersburg Metal Works, 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 :-
The construction of hydraulic lifts adapted to be operated by direct action and
to be raised to considerable heights has hitherto required a stationary cylinder to
be sunk in the ground, which involved considerable expense besides being attended
by great technical difficulties. The plunger rod for instance owing to its very great
length comparatively to its thickness has to withstand a powerful breaking or
bending strain; the consequence being that in order to render it capable of
sufficient resistance it is necessary to proportion its size in a manner inconsistent
with what is required, in regard to diameter, for obtaining the most advantageous
liquid pressure.
In the directly acting hydraulic lift or elevator constructed according to the
present invention these drawbacks are obviated by the employment of a differential
plunger, permanently suspended by its upper end and yet adapted to force the
water required for exercising the hydraulic pressure upwardly.
A lift or elevator embodying these improvements is represented in the accom-
panying drawings in which Figs. 1 and 2 are diagrammatic views of different
positions of the cage while Fig. 3 is a plan of the whole arrangement; and
Figs. 4 to 8 are detail views.
The plunger of the motor or elevating cylinder is a differential plunger or piston
(Figs. 47 and 8) which is made smaller at the upper portion than at the
lower part and is permanently suspended by its upper end, the support K
(Figs. 1, 2 and 4).
Upon this plunger slides the clevating or motor cylinder or pump M
(Figs. 4, 7 and 8) provided with a stuffing box at either end and supporting
the cage O. The lower or thicker portion of the piston rod L assumes the shape
of a tube and it is through this portion that the liquid employed to create hydraulic
pressure is admitted from below (at A. Fig. 4) into the hollow piston rod; whence
through openings provided in the upper end of the thicker portion (at B Fig. 4) it
passes into the motor cylinder or pump.
Owing to such an arrangement the plunger is only submitted to
tension strain
so that nothing prevents its diameter being such as is consistent with the most
advantageous utilization of the liquid pressure available; nor is it necessary to
sink the piston rod underground.
In the example illustrated in the drawings a special method of guiding the rod
and of adjusting its point of suspension is represented; but any suitable means may
be adopted for these purposes if desired.
The cage may be guided in the form of elevator shown by means of a slotted
tube C (Figs. 4, 7 and 8) concentrically surrounding the elevator cylinder or pump
and secured to the wall of the building by means of stays D (Fig. 8). The cage is
provided on diametrically opposite points of its guiding column C with slotted
sliding cheeks E (Figs. 7 and 8). The neck F (Figs. 4 and 8) rigidly secured
to the cage and passing through the slot in the tube C and surrounding the
cylinder or pump by tightly adhering to the edges of the slot in the guiding column
or tube C prevents the cage from turning. At the upper end of the slotted guiding
tube an open attachment or length of the tube G (Figs. 1 and 2) is provided, through
-which-access-may-be-had to the upper stuffing box of the cylinder or pump. Upon
this piece G are erected the required number of tubes H (Figs. 1 and 2) carrying
at their upper ends the support K (Figs. 1, 2 and 4) from which the plunger rod is
suspended.

page_text: Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what I
claim is ;-
1. A hydraulic lift in which upon a stationary plunger rod submitted to tension
strain only there moves a lifting cylinder carrying the cage to which the pressure
liquid is conveyed through the hollow plunger rod substantially as and for the
purpose described.
2. In a hydraulic lift the combination with a movable cylinder such as M which
carries the cage of a plunger or guide rod such as L through which the fluid
is admitted to the cylinder substantially as described.
3. In a hydraulic lift a plunger or guide rod such as L one half or portion
of which is solid and in a state of tension and the other half or portion is hollow
and provided with inlet and outlet openings such as B B substantially as described
and illustrated in Figure 4 of the accompanying drawings.
4. The combination and arrangement of parts constituting the hydraulic lift
apparatus substantially as described and illustrated in the accompanying
drawings.
Dated this 9th day of March 1891.
W. P. THOMPSON & BOULT,
Agents for the Applicant.