Improvements in the Valves of Pneumatic Hammers.
Year: 1894

page_text: Date of Application, 8th Jan., 1894
Complete Specification Left, 29th Aug., 1894-Accepted, 10th Nov., 1894
PROVISIONAL SPECIFICATION.
Improvements in the Valves of Pneumatic Hammers.
I, ENOCH SKINNER of The Fork Works, Ranskill, Nottinghamshire,
Manufacturer, do hereby declare the nature of this invention to be as follows:-
:-
This invention relates to an improved construction of air valve to be attached to
the moving cylinder of a pneumatic hammer by means of which a perfect control
and regulation of the blow may be effected from the lightest to the heaviest that
the hammer is capable of giving.
The valve consists of a rectangular flat plate with a series of slots or holes made
through it in a diagonal or oblique line from top to bottom of the plate or
thereabouts.
This plate is held between a cover plate and a facing formed upon the cylinder,
and a number of slots or apertures preferably of similar size and shape to those
first mentioned are made on a vertical line and opposite each other through the
cylinder and cover plate.
These apertures are so arranged that as the valve plate is moved laterally in the
space between the cover plate and the cylinder face, its diagonally placed apertures
will be brought consecutively exactly opposite to those of the same height in the
cover plate and the cylinder, but in such a manner that only one set of apertures
or air ports is open to the atmosphere and to the interior of the cylinder at one
time, the rest being closed. Thus each aperture or air port from the lowest to
the highest is opened and closed in rotation as the valve plate is moved from one
side to the other.
The valve plate must be provided with means by which it may be moved
laterally as it rises and falls, and preferably by the action of a foot treadle, and
this is conveniently done by a short rack fixed to the projecting top and bottom
ends of the valve plate and actuated by corresponding pinions carried upon a
spindle.
The said spindle is made tubular or partly tubular, with a square opening to
receive the end of a fixed rotating spindle, which end is also made square, and of a
sufficient length for the travel of the cylinder; at the bottom end of this spindle
is a pinion, the teeth of which engage with those of a segmental or other rack
moved by the foot lever.
Dad the 1st dor of Jonur 1891
5
COMPLETE SPECIFICATION.
Improvements in the Valves of Pneumatic Hammers.
I, ENOCH SKINNER of The Fork Works, Ranskill, Nottinghamshire
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 :-
This invention relates to improvements in the construction of the air valve

page_text: attached to the moving cylinder of a pneumatic hammer and by means of which a
perfect control and regulation of the power of the blow may be effected, from the
lightest to the heaviest that the hammer is capable of giving.
The invention is illustrated in the sheet of drawings annexed.
Fig. 1, being an elevation of the valve.
Fig. 2, a plan or view from the top of same.
The valve consists of a rectangular flat plate fitting against a corresponding
flat surface and having a lateral or horizontal movement thereon, it may be
provided with a series of openings for the passage of air, reaching in an oblique
line from the top to the bottom of the plate or thereabouts, or the central
openings may be omitted leaving only a top and bottom opening and I prefer to
use this arrangement, and have therefore shown that arrangement in the drawings.
The valve plate A, in this case has two openings or ports B, B², preferably
simple round holes made through it on the opposite sides of a vertical centre line,
and similar openings are made through the wall of the cylinder communicating with
the interior, and these are placed upon the said centre line, and are indicated by
dotted circles marked C, C².
The position of these air ports is so arranged that when the valve plate A, is at
the end of its lateral movement one of the ports is open and the other one closed,
and when in the central position shown in the drawings each port is half open.
When an oblique series of air ports are used the openings into the cylinder are
made in a vertical line, so that as the plate is moved from side to side, the ports are
alternately opened and closed consecutively from top to bottom or vice versa as the
case may be.
The valve plate A, may be guided in its lateral movement by projecting strips D,
and it is held to the facing on the cylinder by means of bolts E, passing through
horizontal slots F.
The lateral motion of the valve plate while the cylinder is rising and falling
during the working of the hammer is obtained preferably in the manner shown in
the drawings. Two racks G, G2, are either cast upon or attached to the valve
plate A, and two connected pinions H and H³ gear into the said racks and revolve
in the bearing J; these pinions are turned in either direction by means of the
rod I, which is caused to revolve or partially revolve by the foot f the operator,
and which is made either with a long key, or with a keyway, or it be made
square or of other form to pass through a corresponding hole in the pinions, so as
to turn the pinions while they are carried up and down by the action of the
hammer.
"
may
A modification of this arrangement of valve may be made as shown in Figs. 3
and 4 in which the valve plate A, will move vertically so as to open and close
the ports B and B, in which case the valve plate A would be guided between two
side strips K, and have upon its outer face a diagonal path L, in which a finger M
upon a sliding boss N, having a lateral movement, will engage.
When the finger M is moved sideways by turning the vertical rod I, it either
raises or lowers the plate A, and opens or closes the air ports B and B².
An equivalent action would be to have a pin projecting from the back of the
plate A, and engaging with an inclined groove or path of a cam fixed upon or
caused to turn by the rod I, which would pass through it.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, declare that what I
claim, is:
1. The improvements in horizontally or vertically moved valves for pneumatic
hammers, as hereinbefore described, and with reference to the annexed drawings.
2. A horizontally sliding valve for pneumatic hammers, moving with the vertical
action of the air cylinder, and actuated when in any part of its travel, so as to

page_text: open and close a top and bottom port by the means and in the manner substantially
as herein before described, and as shown in Figs. 1 and 2 of the drawings.
Dated the 25th day of August 1894.
ROBT. F. DRURY, C.P.A.,
Bank Buildings, George Street, Sheffield, Agent for Applicant.