IMPROVEMENTS IN THE CONSTRUCTION OF HAND PUMPS
Year: 1879

page_text: LETTERS PATENT to Lorentz Albert Groth, Civil Engineer and Proprietor of the
Scandinavian Patent Office, under the Firm L. A. Groth & Co., of Stockholm,
in the Kingdom of Sweden, for the Invention of "IMPROVEMENTS IN THE
CONSTRUCTION OF HAND PUMPS." A communication from Mr. O. F. Oberg,
at Stockholm.
Sealed the 24th October 1879, and dated the 25th April 1879.
PROVISIONAL SPECIFICATION left by the said Lorentz Albert Groth at the
Office of the Commissioners of Patents on the 25th April 1879.
LORENTZ ALBERT GROTH, Civil Engineer and Proprietor of the Scandinavian
Patent Office, under the Firm L. A. Groth & Co., of Stockholm, in the Kingdom
of Sweden. "IMPROVEMENTS IN THE CONSTRUCTION OF HAND PUMPS." (A com-
munication from Mr. O. F. Oberg, at Stockholm.)
This fire engine or pump consists of a double acting hand pump placed in a
vessel to be filled with water and connected therewith by a peculiar appliance.
The pump consists of a metal tube forming the pump barrel, and another tube
serving as piston rod and air vessel. The hollow piston is provided with ball valve;
a suction valve is arranged at the lower part of the barrel. The piston rod is at
its upper part provided with a spherical outlet chamber, to which the hose is
attached.
The aforesaid vessel, which may be of wood or metal, or both, may be of various
forms, but advantageously of a cylindrical form. An opening with cover serves for
charging it with water; there is a handle for carrying it by. The pump has a
standing position in order that it may not in the carrying by hand be touched and
injured thereby.
The pump works as follows:-When the piston is drawn upwards by taking hold
of the handle, the suction valve opens and the water enters the pump barrel. When
the piston is forced down, the suction valve closes and the piston valve opens for
admitting the water below the piston into the space between the barrel and the
piston rod. After a couple of strokes this space becomes quite filled with water,
and by continued pumping a part of the water also enters the air vessel, compressing
the air therein. Thus an approximately continuous jet is obtained.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Lorentz Albert Groth in the Great Seal Patent Office on the 25th
October 1879.
LORENTZ ALBERT GROTH, Civil Engineer and Proprietor of the Scandinavian
Patent Office, under the Firm of L. A. Groth & Co., of Stockholm, in the Kingdom
of Sweden. "IMPROVEMENTS IN THE CONSTRUCTION OF HAND PUMPS." (A com-
munication from Mr. O. F. Oberg, at Stockholm.)
This fire engine or hand pump consists of two main parts, videlicet, a double acting
suction and force hand pump with hose and a vessel or pail connected therewith
filled with water, and wherein the pump is fixed.
On the accompanying Drawings, A, Figures 1, 2, 3, 4, 5, 6, 7, and 8, is the pail made
of copper, zinc, galvanized sheet iron, or other suitable material; it is made of a
cylindrical form, and holds from 4 to 25 gallons, all according to the size in which it
is made. For holding the pail while pumping it is, as shown in Figures 1, 2, 3, and 4,
formed with a recess E in one side just over the bottom, and fitted with a slanting
foot board e of wood or sheet iron, or as shown in Figures 5 and 6 it is formed with
a stirrup F of iron fastened under the bottom of the pail, between which and the
stirrup is also inserted a slanting foot board G of iron or wood. When the stirrup G
is used the pail is also fitted with a pair of iron feet H, Figures 5 and 6. Lastly,
as shown in Figs. 7 and 8, the pail may be cut off slanting below, and in this part a
stirrup F is arranged which is united with the remaining part of the bucket bottom
by means of the hoop iron G.
The pail may be covered above by means of a lid plate I as in Figures 1, 2, 3,
and 4, or left open as in Figures 5 and 6. In the former case the lid I is either
made with a small circular opening V which can be closed tightly by a small lid K,
Figures 1 and 2, for filling the pail with water; or it may, as shown in Figures 3
and 4, be formed with a larger semicircular opening which can be closed by a lid L.
The former arrangement is preferred for pumps exposed to violent shakes, such as
on board ship or on railway carriages; the latter arrangement is preferred for
ordinary cases, as for house and garden pumps, or where only occasional oscillations
come in question, and where chiefly the evaporation of the water must be prevented.
When a lid is used it is provided with a small hole, Figures 1, 2, 3, and 4; this serves
to receive the end of the jet pipe when the pump is out of use. When the pail is
made open it is provided with a cross stay G, Figures 5 and 6, leaving two holes, a
large one for the pump cylinder to pass through, and a small one for the end of
the jet pipe. Both the open and the covered pail are provided with a handle M,
Figure 1 to 6, for carrying it by.
The pump consists mainly of two parts, namely, the pump cylinder a and the
piston rod b, Figures 1 to 6, working therein; each consists of a piece of drawn brass
or copper tube. The most suitable proportions between the inner diameters of the
pump cylinder and of the piston rod have been found to lie between 25.17 and
31.17. By adhering to these proportions a maximum force with minimum volume of
water is obtained.
The pump cylinder is placed in a slanting position against the axis of the pail,
partly in order to give the arm of the operator a natural and easy movement, and
thus give off the greatest power, and partly in order to facilitate the easier carrying
of the whole pump or fire engine without being hindered by the pump cylinder.
The pump cylinder may be fastened, as shown in Figure 1, by a stay C of hoop iron,
or fastened to the bottom of the pail itself, as shown in Figures 3, 5, and 7. In the
former case it is done by means of a socket D, Figures 1, and as shown more distinctly
in Figure 9, where a is a socket rivetted or soldered on, and ba loose U shaped claimp
plate which by means of the set screw c is pressed against the pump cylinder and
thus holds it firmly. When the pump cylinder is fastened to the bottom of the

page_text: bucket it is done indirectly so that the lower end of the cylinder is screwed on to
a bottom valve piece N, which again is fastened to the bottom of the pail in any
convenient manner. When for instance the lower end of the cylinder is free the valve
N, Figure 1, is screwed thereto in the form shown in Figure 11. The valve itself
is a ball c, and there is a suction opening a below it and a delivery opening b above
it. When the bottom valve is also to serve for connecting the pump cylinder with
the pail bottom it may be of one of the forms shown in Figures 12, 13, and 14. In
Figures 12 are shown two or more feet e rivetted to the pail bottom. In Figures 13
the valve is fastened by means of jointed cross bar h and housing or staple i between
two separate brackets or feet g, g, rivetted to the pail bottom. In Figures 14 the
valve is screwed to a single foot or socket having three feet a rivetted to the pail
bottom. In all three cases the water flows in first through the openings f and then
through the central aperture a as in Figure 11.
When the foot valve is of the kind shown in Figure 11 it is surrounded by a
strainer 8, Figure 1, for preventing solid bodies or dirt from entering into the valve;
this strainer is rivetted or soldered to the bottom of the pail. In the other cases a
strainer of wire netting is soldered under the bottom suction opening of the valve
as shown by the dotted line in Figures 14.
At the upper end of the pump cylinder there is an outlet chamber which is either
some what elongated in the length direction of the cylinder as the chamber O, Figures 1
and 2, or more ball shaped as the chamber P, Figures 3 to 6. This chamber is screwed
on to the pump cylinder at f, and is provided with screwed gland at g for stuffing
box packing around the piston rod. There is also at f soldered on a metal washer
for holding a packing washer. c is the outlet in Figures 1 to 6, and may be arranged
either vertically to the cylinder or slanting to diminish the loss of head. At the
side opposite to c there is a lugd on to which the "spreader" or jet piece is screwed
when not in use. The hose Q is fixed on the outlet c, and its outer end has a conical
part R, Figure 16. On this is screwed a short mouth piece b, Figure 16, of ordinary
construction, or a spreader d shown in Figures 15. The stream is spread in such a
manner that the jet issuing through the holes o, o, cross each other. The mouth
piece b, Figure 16, is used for fire extinguishing, and the jet spreader d, Figures 15,
for garden watering.
The piston rod b is screwed at its lower end for receiving the piston T, Figures 1,
3, 5, and 7, which is fitted with a valve; this valve is shown in section and elevation
at Figure 10. Like the suction vaive it is a ball valve over an aperture a in the pail,
and there are two side openings b, b, above it; the water can ƒ also at b pass into the
interior of the hollow piston rod. There is thus a constant communication between
the space without and within the piston rod above the piston, and on the other band
also a communication between the space above and within the piston depending
upon the play of the ball valve c. The upper end of the piston rod is closed tight
by a brass handle U soldered on, Figures 1 and 2, or by a soldered on brass piece u
with wooden handle U screwed on, Figures 3, 4, 5, and 6.
This pail pump or fire engine works as follows:-The pail being charged with
water the latter enters the pump up to the same level. When the piston is forced
down the suction valve is closed and the piston valve opens; in the upstroke of the
piston the piston valve closes and the suction valve opens. The water between the
Buction valve and the piston will therefore in the down stroke of the piston pass
through the valve in the piston and enter the space inside and outside the piston rod.
As this space gradually becomes filled the water will by the continued down motion
of the piston be forced into the delivery chamber, and thence into the hose. The
water will also in the upstroke of the piston issue from the hose; but as in each
upstroke water is drawn in by the suction valve as aforesaid, it follows that in the
upstroke the pump simultaneously draws and forces, or is double acting, inasmuch as
in the down stroke no water is drawn in but only forced out, being then single
acting; the pump thus forcing out water both in up and in down stroke a continuous
and strong jet is produced. To give the water in the jet pipe the greatest and best

page_text: velocity the proportion of diameter of the pump cylinder and the jet piece should
be about 25 to 4 or 31 to 4.
When pumping with normal speed the whole entering volume of water cannot
freely pass out of the jet pipe because of its smaller diameter without pressure being
created in the pump, and this pressure drives out the water through the side openings
from the piston rod, which thus acts as an air vessel The upper part of the
chamber O, Figure 1, also serves as an air vessel.
And having thus described this Invention I am now aware that it has heretofore
been proposed to fix a double acting pump having two valves only and a hollow
plunger at an angle in a pail, I do not therefore broadly claim such a construction.
I would also state that hand pumps for fire extinguishing as heretofore usually made
act on the principle of maximum volume and greatest distance thrown of the liquid
employed, whereas the hand pump made according to this Invention, and because of
the special form or proportions of the hollow plunger and the barrel act on the
principle of maximum force of jet by the employment of a minimum volume of
water. Neither do I broadly claim the use of a ball delivery valve and foot valve
for double acting pail pumps, but I claim,-
First. The hollow plunger and the pump barrel of the relative proportions herein-
before indicated for the purpose set forth in combination with a foot valve and
piston valve of the construction described with reference to the accompanying
Drawings, the pump being fastened in a slanting position in a pail as set forth.
Second. The special construction of delivery valve as described with reference to
Figure 10.
Third. The special construction of foot valves and the modes of fastening the
same as described with reference to Figures 12, 13, and 14.
In witness whereof, I, the said Lorentz Albert Groth, have hereunto set my
hand and seal, this Twenty third day of October, in the year of our Lord
One thousand eight hundred and seventy nine.
Witness,
PETER JENSEN,
33, Chancery Lane.
LORENTZ ALBERT GROTH. (L.S.)