IMPROVEMENTS IN HYDRAULIC ELEVATORS
Year: 1876

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, and temporarily of Paris, France, for the
Invention of "IMPROVEMENTS IN HYDRAULIC ELEVATORS." A communication
by Jacob Hahn, residing in the City of New York, United States of America.
Scaled the 25th July 1876, and dated the 9th March 1876.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 9th March 1876.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, and temporarily of Paris, France. "IMPROVEMENTS IN HYDRAULIC
ELEVATORS." A communication by Jacob Hahn, residing in the City of New York,
United States of America.
My Invention relates to that class of elevators in which hydraulic pressure is
used, and the main object sought to be secured is economy in the use of water.
My Invention consists in the combinations of parts herein-after explained.
Figure 1 of the Drawing annexed shows a vertical section of the improved
elevator.
A represents the outer casing or cylinder provided with the inlets a, a¹. On each
side of the casing A is secured a suitable framework to sustain the pulleys 1, 1,
and 2, 2. From this framework rises the vertical guides B, B, for the cross head C.
Within the cylinder A works the hollow piston D, the upper portion of which is
connected by suitable means to the cross head C. Again, within the hollow piston D
is a stationary hollow cylinder E secured to the bottom of cylinder A. Thus the
piston D moves and operates between the interior of the cylinder A and the exterior
of the cylinder E, for purposes herein-after explained. Again within the cylinder E
is fitted to operate the piston F, having a hollow piston rod f reaching nearly to
the top of the cylinder E. Again within the hollow piston rod or cylinder f is
snugly fitted and operated the piston G. This hollow rod or cylinder f is provided
with a valve g at its bottom, for a purpose herein-after explained. Attached to the
piston G is the piston rod I, the opposite or upper end of which is connected with
the cross head C by any suitable means. Through the base of the casing or
cylinder A I arrange the inlet openings a, a, for the passage of the water from the
connecting pipes. The opening a enters the cylinder A immediately under tho
Duina C1

page_text: piston D, and supplies the water for raising that piston. The opening a¹ enters the
cylinder A immediately under the piston F, and supplies the water for raising that
piston. The pipes conducting the water to the openings a and a¹ may be supplied
with discharge cocks of any of the well-known styles.
The operation of the apparatus is as follows:-The elevator being ready to
ascend water is admitted through the opening a, and the pressure raises the
piston D, and with it the piston rod I, both being connected with the cross head C;
the result will be the equal ascent of the pistons D and G. As the piston G riscs
in the hollow rod or cylinder f, the dead water resting in pipe below the cock enters
through the valve g into and fills the cylinder f. Let us suppose the elevator has
reached the third floor of the building, and some additional weight is added to the
load and the main piston D is unable to rise further. Water is admitted through
the opening a¹ and under the piston F. This piston then rises, and as the valve
closes and prevents the escape of the water from under the piston G, the piston F
carries with it the piston G and piston rod I, and an additional power is thus added
to the piston D to aid in raising the elevator. By this construction it is evident that
I am able to bring tho the auxiliary piston F into immediate action when needed.
It remains in position to receive the hydraulic pressure while the piston G and
rod I move up with the piston D, and practically become an elongated rod to the
piston F, ready to catch the pressure and come to the aid of piston D whenever
additional aid is required.
It is evident from the above description that instead of the stationary hollow
cylinder E a moving cylinder could be used, with a piston fitting in the cylinder A
and placed below the piston D; but this arrangement is objectionable, as it
necessitates the raising of the large body of water below the cylinder D, whereas
by my construction the piston F has only to raise the small body of water below
the cylinder G.
It is also evident that the number of cylinders and pistons may be increased
without departing from the spirit of my Invention.
Any well-known arrangement of supply and exhaust cocks may be used. When
the exhaust cocks are opened the pistons will all gradually descend, and when the
piston Frenches the bottom of cylinder E, the valve g will be raised from its seat
and opened by the short rod i, and the piston G will be allowed to continue its
descent until it reaches the bottom of the cylinder f.
Figure 2 is a sectional clevation of the main cylinder A and hollow piston D,
and an inner cylinder E¹ and piston F¹ in a modified arrangement, by which I
propose to use the latter for nearly balancing the platforms, both in ascending and
descending, so that the water for that purpose will not be wasted, but will be forced
back when the elevator descends through the supply pipe by which it enters when
the elevator ascends. The pipe / will in this case be always open between the
supply and the inner cylinder, the area of which will be such that the pressure on
its piston will not quite equal the weight of the elevator without its load. The
weight of the elevator will force the water of the inner cylinder back to be used
over again, and so that in the descent only the water used under piston D which
raises the load will be exhausted. The rod f' of piston F' will be connected to the
cross head C.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Melville Clark in the Great Seal Patent Office on the
7th September 1876.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, and temporarily of Paris, France. "IMPROVEMENTS IN HYDRAULIC
ELEVATORS." A communication by Jacob Hahn, residing in the City of New
York, United States of America.

page_text: This Invention relates to that class of clevators in which hydraulic pressure is
used, and the main object sought to be secured is economy in the use of water.
The Invention consists in the combinations of parts herein-after explained and
claimed.
Figure 1 of the Drawing is a perspective view of the hydraulic device; Figure 2
is a vertical section of the same; Figure 3 is the same, showing the main piston
rising; Figure 4 is the same, showing the auxiliary piston brought into action.
Figure 5 is a horizontal section, showing the inlet pipes.
A represents the outer casing or cylinder provided with the inlets a, a¹. On cach
side of the casing A is secured a suitable framework to sustain the pulleys 1, 1,
and 2, 2. From this framework rises the vertical guides B, B, for the cross head C.
Within the cylinder A works the hollow piston D, the upper portion of which is
connected by suitable means to the cross head C. Again, within the hollow piston D
is a stationary hollow cylinder E, secured to the bottom of the cylinder A; thus the
piston D moves and operates between the interior of the cylinder A and the exterior
of the cylinder E, for purposes herein-after explained. Within the cylinder E is
fitted to operate the piston F, having a hollow piston rod f reaching nearly to
the top of the cylinder E, and within the hollow piston rod or cylinder fis
snugly fitted and operated the piston G. This hollow rod or cylinder f is provided
with a valve g at its bottom, for a purpose herein-after explained. Attached to the
piston G is the piston rod I, the opposite or upper end of which is connected with
the cross head C by any suitable means. Through the base of the casing or
cylinder A I arrange the inlet openings a, a¹, for the passage of the water from
the connecting pipes. The opening a enters the cylinder A immediately under the
piston D, and supplies the water for raising that piston. The opening a¹ enters the
cylinder A immediately under the piston F, and supplies the water for raising that
piston. The pipes conducting the water to the openings a and a¹ may be supplied
with discharge cocks of any of the well-known styles.
The operation of the apparatus is as follows:-The elevator being ready to
ascend water is admitted through the opening a, and the pressure raises the
piston D, and with it the piston rod I, both being connected wiu. the cross head C;
the result will be the equal ascent of the pistons D and G. As the piston G rises
in the hollow rod or cylinder f, the dead water resting in pipe below the cock
enters through the valve g and opening a¹ into and fills the cylinder f. Let us
suppose the elevator has reached the third floor of the building, and some additional
weight is added to the load and the main piston D is unable to rise farther. Water
is admitted through the opening a¹ and under the piston F. This piston then rises,
and as the valve g closes and prevents the escape of the water from under the
piston G, the piston F carries with it the piston G and piston rod I, and an
additional power is thus added to the piston D to aid in raising the elevator. By
this construction it is evident that I am able to bring the auxilliary piston F into
immediate action when needed. It remains in position to receive the hydraulic
pressure, while the piston G and rod I move up with the piston D to aid in raising
the elevator. By this construction it is evident that I am able to bring the auxiliary
piston F into immediate action when needed. It remains in position to receive the
hydraulic pressure, while the piston G and rod I move up with the piston D and
practically become an elongated rod to the piston F, ready to catch the pressure
and come to the aid of piston D whenever additional aid is required.
It is evident from the above description that instead of the stationary hollow
cylinder E a moving cylinder could be used, with a piston fitting in the cylinder A
and placed below the piston D. But this arrangement is objectionable, as it
necessitates the raising of the large body of water below the cylinder D, whereas
by the arrangement above described the piston F has only to raiso the small body
of water below the cylinder G.
It is also evident that the number of cylinders and pistons may be increased
without departing from the spirit of the Invention.
Any well-known arrangement of supply and exhaust cocks may be used.
When

page_text: the exhaust cocks are opened the pistons will all gradually descend, and when the
piston F reaches the bottom of cylinder E the valve g will be raised from its seat
and opened by the short rod i, and the piston G will be allowed to continue its
descent until it reaches the bottom of the cylinder f.
Figure 6 is a sectional elevation of the main cylinder A and hollow piston D,
and an inner cylinder E and piston F1 in a modified arrangement, by which I
propose to use the latter for nearly balancing the platforms, both in ascending and
descending, so that the water for that purpose will not be wasted, but will be forced
back when the elevator descends through the supply pipe by which it enters when
the elevator ascends. The pipe will in this case be always open between the
supply and the inner cylinder, the area of which will be such that the pressure on
its piston will not quite equal the weight of the elevator without its load. The
weight of the clevator will force the water of the inner cylinder back to be used
over again, so that in the descent only the water used under piston D which raises
the load will be exhausted. The rod f¹ of piston F will be connected to the cross
head C.
Having described the nature of the said Invention, and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
herein-before in part recited Letters Patent is,
1st. In a hydraulic elevator the hollow cylinders A and E in combination with
the hollow piston D and cross head C, substantially as and for the purpose
described.
2nd. In a hydraulic elevator the hollow cylinders A and E and hollow piston D
in combination with the piston F and cross head C, substantially as and for the
purpose set forth.
3rd. In a hydraulic elevator the hollow cylinders A and E and hollow piston D
in combination with the piston F, hollow rod f, piston G, rod I, and cross head C,
substantially as and for the purpose set forth.
4th. The combination with the cylinder and piston for raising the load of a
cylinder and piston always open to the water supply for nearly balancing the
elevators, both in ascending and descending.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Seventh day of September, in the year of our Lord
One thousand eight hundred and seventy-six.