IMPROVEMENTS IN THE PNEUMATIC MECHANISM OF POWER-HAMMERS
Year: 1886

page_text: Date of Application, 20th May, 1886.
Complete Left, 19th Feb., 1887.
Complete Accepted, 22nd Mar., 1887.
DEC
I, GILBERT GLOSSOP 114 Victoria Road, Heeley, Sheffield in the County of York,
Manufacturer do hereby declare the nature of my said invention for IMPROVEMENTS
IN THE PNEUMATIC MECHANISM OF POWER-HAMMERS to be as follows:-
My invention relates particularly to the construction and arrangement of the
pneumatic action of Power-Hammers, that is, Hammers driven by a belt or similar
means in contra distinction to steam Hammers, the object of the pneumatic action
being to relieve the mechanical parts of the hammer from the shock of the blow when
the hammer is striking by the interposition of a cushion of air.
This cushioning by imprisoned air, is I am well aware, already carried out in various
ways, and therefor I do not lay any claim to the principle, but only to the method of
applying the said principle and the mechanical details of such pneumatic action..
In carrying out my invention as applied to a power hammer driven by a belt from
a main shaft, for example, I fix upon the top of the framework of the Hammer an
eccentric shaft provided with the necessary driving pulley and fly wheel.
A connecting rod upon the eccentric, depends vertically and is connected to the top
of a short air-cylinder which can work up and down in slides projecting from the
hammer standard.
A piston rod passes through a stuffing box in the underside of the cylinder, and
is provided with a suitable piston which fits the cylinder, the bottom end of the rod
being attached to the tup which is also made to slide in guides attached to the frame
or standard of the hammer.
The cylinder is provided with air-valves, one near the top and one near the bottom,
which are arranged to open and admit air into the cylinder when the interior pressure
is less than that of the atmosphere, and to close when it exceeds it.
When the eccentric shaft revolves, the connecting-rod imparts a vertical reciprocating
motion to the cylinder, which transmits the said motion to the piston rod and tup;
the piston is prevented striking the top or bottom of the cylinder by a cushion of
compressed air, drawn in the top valve as the cylinder ascends and leaves the piston
and up behind, and in at the bottom valve when it outstrips the piston in descending.
Any suitable stopping and starting motion or gear may be adopted.
Dated the 18th day of May 1886.
ROBT. F. DRURY,
Agent for the Applicant.

page_text: Improvements in the Pneumatic Mechanism of Power Hammers.
I, GILBERT GLOSsor, 114 Victoria Road, Heeley, Sheffield in the County of York
Manufacturer 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 particularly to the construction of pneumatic hammers, and
more particularly to the construction of the moving air cylinder of such hammers,
with the object of cushioning the piston end of the tup rod and thus relieve the various
parts of the hammer that would otherwise suffer, if allowed to come in contact when
the blow is struck, or when the tup is being raised.
The cushioning by imprisoned air, is I am well aware already carried out in various
ways and therefore I do not lay claim to the principle, but only to my particular
method of applying the said principle and to the novel method of carrying the same
into practice.
And in order that my invention may be clearly understood I have annexed hereto
a sheet of drawings illustrating its application to a Power Hammer, in which the same
letters of reference will indicate the same parts in any of the figures.
Fig. 1, is a front elevation of a power Hammer showing how my invention is applied
to the air cylinder.
Fig. 2, is an enlarged sectional view of the inlet valve.
In carrying out my invention as applied to a power hammer driven by a belt, such
as shown in Fig. 1 of the drawings for example, in which an air cylinder has a vertical
reciprocating motion imparted to it by the direct application of a connecting rod from
a crank or eccentric on the driving shaft, and which in turn is enabled to lift the tup
by means of a piston rod, the piston being cushioned by compressed air at each end
of the stroke; A is the connecting rod, the crank, the air cylinder, D the slides
in which the cylinder works, fixed to the standards E.
The piston rod F passes through a stuffing box G, and is provided with a suitable
piston which fits the cylinder, the bottom end of the rod being secured to the tup H,
which also slides in suitable guides.
The cylinder C, is provided with one or more air valves I, if one only is used it will
be placed in a central position or thereabouts, but if two valves are used, one is placed
near the top and the other near the bottom of the Cylinder.
In the Hammer shown, two inlet valves are used I, I, they are made as shown in
the sectional drawing Fig. 2. Jis the spindle, K is a stop to regulate the amount
of movement of the valve, C is the Cylinder. It will be readily seen that when the
pressure inside the cylinder in less than that of the atmosphere, the valve will be
moved towards the stop K, and air will be admitted into the Cylinder, but the moment
the pressure in the Cylinder exceeds that of the atmosphere, either by compression
or otherwise, the valve is immediately closed and escape prevented.

page_text: At the back of the Cylinder I arrange one or more escape valves that may be.
opened and closed by means of a foot or hand lever, for the purpose of regulating the
amount of cushioning power in the Cylinder, and thus adjusting the force of the blow.
This great desideratum which is accomplished without altering the speed of the
hammer is caused by varying the amount of confined air in each end of the Cylinder
and thus increasing or diminishing the reacting power contained in the compressed
air between the piston and the ends of the Cylinder.
When the eccentric or cranck shaft B, is made to revolve, the connecting rod A,
imparts a vertical reciprocating motion to the Cylinder C, which transmits the said
motion to the piston rod F, and Tup H. The piston is prevented striking the top or
bottom of the cylinder by reason of the enclosed air at each end.
Oweing to the impetus of the tup, the Cylinder at each end of its movement is
travelling in the opposite direction to that of the piston, thus compressing the confined
air with great power and causing it to react upon the tup through the piston, with
corresponding force.
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 In pneumatic hammers, the combination with a vertically moving air Cylinder
(such as C), of one or more valves (such as I) constructed to admit air to the Cylinder
when the outside atmospheric pressure exceeds that of the interior, and to close when
the interior pressure exceeds that of the outer for the purpose specified and substantially
as hereinbefore described and illustrated.
2-In the construction of air Cylinders for Pneumatic Hammers, the application
of one or more automatic inlet air valves, in combination with one or more escape
air valves worked by hand or foot lever, for the purpose specified and substantially as
described.