provements in or connected with Pneumatic Pumps.
Year: 1897

page_text: PROVISIONAL SPECIFICATION
Improvements in or connected with Pneumatic Pumps.
I, JOHANN STROMEL, of 199, Rossmarkt, Landsberg-on-Lech, in the Empire of
Germany, do hereby declare the nature of this invention to be as follows:-
This invention relates to a pneumatic pump which, by means of a manometer
of suitable construction standing in direct connection with the air cylinder of
the pump and mounted on one end of the inner tube, enables the pressure in the
tyre to be read off or ascertained at any time during and after the inflation.
This pneumatic pump differs in its outer form from those hitherto employed
mainly by a manometer being attached to the tube forming the piston whilst
the internal construction is as follows:-
a
An outer tube having at one end a screw nozzle for the connecting pipe and at
the other end a guide piece or cap forming a guide for an inner tube, forms the
actual wellknown air cylinder. The pressure piston is formed by the inner tube,
a valve body bearing a leather disc or washer being arranged at the upper end
of said tube whilst a manometer case is mounted at its lower end. The mano-
case, of
meter itself consists in addition to the already mentioned
spirally
wound tubular spring which is in communication by means of a hole with the
hollow interior of the piston tube which is closed at its other end by a valve of
any suitable kind and said manometer by means of a finger indicates on a scale
imprinted on a figure dial the actual pressure. A glass diso is arranged on
a rubber or the like ring over the manometer and is retained by a fastening ring.
The mode of action of the pump is as follows:-
:-
As soon as the pressure in the tyre or the like becomes by inflation greater
than that in the manometer chamber the valve will open and the excess pressure
pass through into the hollow interior of the inner or piston tube and from thence
through the manometer hole into the tubular spring which is influenced in the
usual manner and indicates the pressure. When the manometer indicates the
desired pressure the guarantee is afforded that the same pressure also exists in
the tyre owing to the circumstance that the pressure can constantly equalise itself
between the tyre and the manometer. In order to empty the manometer
chamber it only requires a screw to be unfastened to open a port leading to the
outer air when the pointer will again return to zero.
1
1007

page_text: Improvements in or connected with Pneumatic Pumps.
I, JOHANN STROMEL, of 199, Rossmarkt, Landsberg-on-Lech, in the Empire of
Germany, 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 a pneumatic pump fitted with a manometer or pressure
gauge, mounted on one end of the hollow central tube forming the piston road
of the pump, and also placed in direct connection with the air chamber of the
pump.
It is thus evident, that, when the pump is employed for inflating cycle and
other tyres and the like, for which purpose it is specially adapted, the air pres-
sure existing in the tyre or article inflated can be read off at any time during
and after inflation.
In outward appearance this pump differs chiefly from those hitherto employed
in being provided with the aforesaid manometer or gauge.
The details of the pump are represented in the accompanying drawings
wherein:
Fig. 1 shows a longitudinal section of the pump, and
Fig. 2 a front view of the manometer.
Referring to both these figures,
a is the main cylinder of the pump;
6 the screw cap and nozzle, through which the air is discharged;
c is the hollow cylinder acting as piston rod;
d a collar serving as guide for the piston-rod;
f&e the piston and attached leather-disc.
g is the case enclosing the pressure gauge and connects the piston rod c with
the outer guide tube h;
i is the indicator of the said gauge;
ka spiral tubular spring which, by means of a boring / communicates with the
interior of the hollow piston;
m is the dial of the indicator;
n a glass disc covering the dial-plate and cutting off all communication between
the gauge and the external air. It is supported by a ring of rubber or the
like o and kept in position by a fastening ring ?;
q is a valve fitted to the body of the pump piston and transmitting air to the
hollow piston rod and pressure gauge. Being constructed in such a manner as to
have the same resistance or tension as the valve in the cycle-tyre, it opens when
the pressure of air in the pump cyclinder is equal or superior to that in the tyre;
and in this way transmits to the gauge the pressure existing in the tyre.
s is a screw for releasing the compressed air from the hollow piston rod when
the inflation is completed.
The method of working the pump is as follows:
The pump is attached to the tyre-valve in the usual manner and set in motion
until the internal pressure is superior to that within the tyre. When this is the
case, the tyre valve and pressure gauge valve q being of equal resistance open
simultaneously and an equilibrium of pressure is thus set up inside both tyro
and pump and is recorded by the movement of the pointer on the dial plate of the
gauge.
When the tyre is sufficiently inflated, the pump is disconnected, and the pres-
sure in the hollow piston rod c relieved by unscrewing the releasing screws, thus
allowing the indicator to return to zero on the dial plate.

page_text: The purpose for which my invention is most particularly adapted is the
inflation of the cycle tyres, air-cushions, air beds and other similar articles, which
require to be inflated.
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. A pneumatic pump fitted with a manometer or pressure gauge for recording
the pressure produced, substantially as set forth and represented in the drawings.
2. In a pneumatic pump fitted with a manometer or pressure gauge for record-
ing the pressure produced, the employment of a hollow piston rod for trans-
mitting air under pressure to the pressure gauge, substantially as set forth and
represented in the drawings.
3. In a pneumatic pump fitted with a manometer or pressure gauge for record-
ing the pressure produced, the employment of a valve for securing equilibrium
of pressure between the pressure gauge of the pump and the interior of the
article inflated substantially as set forth and represented in the drawings.
4. In a pneumatic pump fitted with a manometer or pressure gauge for record-
ing the pressure produced, the employment of a releasing screw for relieving the
pressure on the gauge, when the operation of inflating is terminated, substan-
tially as set forth and represented in the drawings.
T
1000