Improvements in Hydraulic Jacks.
Year: 1899

page_text: Date of Application, 3rd Jan., 1899-Accepted, 11th Feb., 1899
COMPLETE SPECIFICATION.
Improvements in Hydraulic Jacks.
I, JOIN WEEKS, Manufacturer, of 24, Columbia Street, Borough of Manhattan,
City of New York, County and State of New York, 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: -
My invention relates to improvements in hydraulic jacks, of the kind in which
two pumps are employed of different capacities, so that the ram can be quickly
pumped up against the load, and thereafter, or when desired for the purpose of
exerting greater power, the larger pump will be "thrown out" and the smaller
one employed.
The invention, more particularly described, relates to improvements in the
means whereby the large pump is thrown out," and also the lowering of the.
ram effected.
"
Referring to the drawings hereof:
Figure 1 is a vertical, sectional view of the ram and its interior mechanism.
Figure 2 is a top view of the pump block.
Figure 3 is a bottom view of the pump block.
A is the usual casting for the jack, B is the ram cylinder, C is the ram; D is
the packing ring on the ram, and E is the packing. F is the lever socket, G the
knuckle, H the knuckle-head. I is the pump block, which is set in a suitably
shaped recess made in the bottom or under side of the casting A, and is held in
place by threaded nuts J and K respectively. L is the plunger for the big
pump, M the plunger for the small pump. These pumps are provided respec-
tively with the usual stemmed egress valves, N and 0 respectively, each provided
with perforated bonnets, springs, &c., and the plungers are provided with suitable
packing. All these parts may be of any usual or preferred form, and do not
require special description.
P is a circular block threaded at Q to the casting A of the jack, and in the
center of this an opening is made, through which the spindle R passes. This
spindle is provided with a hand-wheel S on the exterior of the jack. T is a collar
on the spindle, which is seated in a suitably formed recess in the block P, and
is confined by a leather washer T and gland T. The washer is used to prevent
leakage when the jack is used horizontally. The spindle, consequently, has rotary
motion, but cannot move longitudinally. The lower end of the spindle R is
threaded into a block U, so that as the spindle is rotated by the hand-wheel S, the
threads on the spindle will cause the block U to move vertically, up or down
depending upon the direction in which the spindle is turned; and in order to
prevent the block U from turning, a pin V, which is rigidly fastened to the
plug W (which latter is threaded into a solid part of the pump block I) enters
and loosely fits a hole a made in the vertically moving block U.. The hole is
made longer than the pin, so that the upper end of the pin will not strike against
the upper end of the hole during the movement of the block.
b is the stem of a valve which is the relief or by-pass valve for the big pump;

page_text: it has its seat in the lower end of the screw-plug W, and its upper end is fastened
in the block U. The valve is shown at c, and below the valve the stem proceeds
downwardly, as at d. The stems and d are made three-cornered, or flattened
in cross-section, so that the liquid may pass up by their sides, as usual in such
construction.
Referring now to the pump bores and the various water passages, special refer-
ence being had to Figures 1 and 2:
e is the bore in the pump block made for the larger pump; f is the bore for
the smaller pump, g is the bore for the lowering and by-passing" mechanism
for the large pump, which has been already partly described. The spindle bis
shown in Fig. 2 as resting in this bore. At the bottom of the big pump, a water
passage, h, is made into the boring g, so that the liquid expelled by the big
plunger passes through this opening into the passage in which the lowering and
"by-passing" devices, above referred to, are located; thence downwardly, through
a stemmed valve into a passage j; and thence through a passage k, which like-
wise connects with the bottom of the small pump. Through these passages the
liquid is conveyed from both of the pumps to the chamber beneath the ram.
The construction of the lowering and "by-passing" devices is such that when
the relief valve c is on its seat in the plug W, then the lower end of the stem d
is separated by a space of one-quarter or one-half an inch, more or less, from
the upper end of the stem of the valve i, so that upon turning the hand-wheel S,
the block U, carrying the valve and the stem d below it, may be depressed so
far as to completely open the valve c without the stem d coming in contact with
the upper end of the stem of the valve i; but when desired, the hand-wheel S
being further rotated, the threads on the ends of the spindle R will depress the
block U so far that the lower end of the stem d will come in contact with the
upper end of the stem of the valve i, so that this valve may be forced from its
seat.
The operation of the apparatus is as follows: The jack, being placed under its
load, in order to pump the ram quickly up to the load, the hand-wheel S is ro-
tated until the valve c is fully seated in the screw-plug W. Thereupon, the pump-
ing lever being operated as usual, both of the pumps receiving the liquid from
the reservoir (which, of course, is the entire unoccupied portion of the jack casing)
forces it into the chamber beneath the ram. The liquid from the large pump
passes through the opening h downwardly beside the spindle of the valve i, forces
that valve off its seat; thence through the passage into the passage k, and
from it into the chamber beneath the ram; and the liquid from the small pump
passes, in like manner, downward through the egress valve at its lower end, and
discharges into the same passage k. As soon as the ram has in this manner been
quickly elevated against its load, when the weight becomes too great for the
convenient operation of the combined pumps, (it is immaterial whether this
occurs as soon as the ran has taken a bearing against the load, or later) then, in
order to "throw out" the big pump, the hand-wheel S is turned in such manner
as to depress the threaded block U. In its descent it carries the relief valve c
with it, so that that valve is unseated; but it is not depressed so far as to unseat
the egress valve of the big pump, merely sufficient to open the relief valve c.
The pumping operation is now continued, and it will be observed that the small
pump only is in operation, because the liquid which the big pump manipulates
passes through the opening hand thence, since the relief valve cis now open, it
does not press the egress valve i off its seat; on the contrary, the liquid rises by
the sides of the stem d, through the valve c, thence upwardly through the
threaded plug W, by the sides of the spindle b, and discharges at the upper sur-
face of the threaded plug W back again into the reservoir, so that, as the parts
are now arranged, the big pump does no effective work, it merely churns the
liquid back and forth, taking it from the reservoir and discharging it into the
reservoir. Meantime, however, the small pump is doing its regular work, forcing
the liquid from the reservoir downwardly through its egress valve into the

page_text: passage k, and thence into the chamber beneath the ram; and the egress valve i
of the big pump prevents backward flow of the liquid forced into the ram chamber
by the small pump, because as yet it has not been unseated.
As soon as the load has been elevated to the desired height and suitably sup-
ported, in order to get the jack out from under it it is necessary, as is well under-
stood, to allow the liquid in the force chamber of the ram to escape therefrom
This is effected by still further turning the hand-wheel S, so that the block U is
still further depressed and the stem d is now brought in contact with the upper
end of the stem of the egress valve i. Then, sufficient power being applied to the
hand-wheel S, that valve i will be forced off its seat, whereupon free return
passage will be opened from the force chamber of the ram through the passage k
in the pump block, through the cross-passage j, upwardly through the now
opened egress valve i, and thence by the side of the stem of that valve and the
stem d, through the relief valve c, which is likewise unseated at this time, and
still upwardly by the sides of the stem b, and out at the top of the threaded
plug W into the reservoir again.
It will be seen that by the peculiar construction and arrangement of the de-
vices shown, the means for throwing the big pump out and for effecting the
lowering of the ram are durable, simple, easily operated, and of such a character
as will not get out of order.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:
1. The combination, in an hydraulic jack, of two pumps, each provided with
an egress valve and each connecting with the force chamber of the ram; a sup-
plemental passage connecting the bore of the large pump with the reservoir; a
relief valve in said passage; a threaded stem, actuated from the exterior of the
jack, adapted to unseat the relief valve and likewise, when given additional move-
ment, adapted to unseat the egress valve of the large pump, for the purposes set
forth.
2. The combination, in an hydraulic jack, of two pumps, each provided with
an egress valve and both connecting with the force chamber of the ram; a pass-
age connecting the bore of the large pump with the reservoir and likewise con-
necting with the passage from the pumps to the force chamber of the ram; a
relief valve in said passage; and a threaded stem, actuated from the exterior of
the jack, adapted to unseat the relief valve and likewise, when given additional
movement, to unseat the egress valve of the large pump, for the purposes set
forth.
3. The combination, in an hydraulic jack, of two pumps, each provided with
an egress valve and both connecting with the force chamber of the ram; a sup-
plemental passage connecting the bore of the large pump with the reservoir and
connecting also with the passage leading to the force chamber of the ram; two
valves set in said first named passage, one of them the relief valve and the other
the egress valve for the large pump; and means, actuated from the exterior of
the ram, adapted to unseat the relief valve upon a certain degree of movement
and to hold it unseated and to unseat the egress valve upon additional movement,
for the purposes set forth.
4. The combination, in an hydraulic jack, of two pumps, one larger than the
other; a supplemental passage which forms part of the connection between the
larger pump and the force chamber of the ram; two valves set in said passage,
one the relief valve for the large pump and the other its egress valve; and means
substantially as described, whereby said relief valve may be first unseated and
then the egress valve unseated, for the purposes set forth.
5. The combination, in an hydraulic jack, of a pump block having three bor-
ings, two of them for pumps and one for a combined lowering device and means
for throwing out” one of the pumps; a water passage connecting one of the
"

page_text: pumps with said third boring; two valves set in said third boring, one a relief
valve for said pump and the other its egress valve; and means located in said
boring, actuated from the exterior of the jack, whereby the relief valve may be
first unseated and then, being additionally moved, the egress valve unseated, for
the purposes set forth.
6. In an hydraulic jack having two pumps, a relief valve and the egress valve
for one of the pumps set in the same line, and that line different from the axial
line of the said pump, and means substantially such as described, for unseating
said relief and egress valves, for the purposes set forth.
Dated this 5th day of December 1898
JOHN WEEKS,
H. D. Fitzpatrick,
100, Wellington Street, Glasgow, Agent.
JOHN WEEKS,
H. D. Fitzpatrick,
100, Wellington Street, Glasgow, Agent.