Improvements in and connected with Valves for Percussive Rock Drills, Direct Acting Pumps, and Engines.
Year: 1893

page_text: Date of Application, 13th June, 1893
Complete Specification Left, 6th Mar., 1894-Accepted, 14th Apr., 1894
PROVISIONAL SPECIFICATION.
Improvements in and connected with Valves for Percussive Rock
Drills, Direct Acting Pumps, and Engines.
We, ALBERT WILLIAMS DAW, and. ZACHARIAS WILLIAMS DAW, both of
Mansion House Chambers, No. 11 Queen Victoria Street, in the City of London,
Mining Engineers, do hereby declare the nature of this invention to be as
follows:-
:-
The present invention relates to the employment of an auxiliary valve for
controlling the exhaust of the pistons which actuate the main valve for governing
the supply and exhaust passages for actuating the main piston of reciprocating
engines, such auxiliary valve being itself actuated by passages controlled by the
main piston.
For this purpose an auxiliary valve is arranged to work in a cylinder the
opposite ends of which are connected by passages leading to near the opposite ends
of the cylinder in which the piston of the reciprocating engine works, and which
piston in its to and fro movements opens and closes such passages, so that when one
side of such main piston is open to exhaust, the corresponding end of the auxiliary
valve cylinder is also open to exhaust, while the opposite end of the auxiliary valve
cylinder is through the other passage open to the supply which is then acting on
the opposite side of the main piston. The auxiliary valve is thus shot over from
one end of its cylinder to the other, and in its movement shuts a passage leading
to one end of the cylinder in which the main valve works, while it opens a second
passage leading to the opposite end of the main valve cylinder to the main
exhaust.
The construction of the main valve and the arrangement of the ports or passages
for actuating same may be similar to that set forth in the Specifications of our prior
Patents, Nos. 8873 dated 9th June 1890 and 11,216 dated 18th July 1890, but the
passages connecting the ends of the main valve cylinder with the passages leading
to the ends of the main piston cylinder will not be necessary, as the connection with
the exhaust in the present arrangement will be effected through the auxiliary valve
cylinder.
Dated this 14th day of June 1893.
ALLISON BROS.,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in and connected with Valves for Percussive Rock
Drills, Direct Acting Pumps, and Engines.
We, ALBERT WILLIAMS DAW, and ZACHARIAS WILLIAMS DAW, both of
Mansion House Chambers, No. 11 Queen Victoria Street, in the City of London,
Mining Engineers, 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 :-
1
The present invention relates to the employment of an auxiliary valve for
controlling the exhaust of the pistons which actuate the main valve for governing
the supply and exhaust passages for actuating the main piston of reciprocating

page_text: engines, such auxiliary valve being itself actuated by passages controlled by the
main piston.
For this purpose an auxiliary valve is arranged to work in a cylinder the
opposite ends of which are connected by passages leading to near the opposite ends
of the cylinder in which the piston of the reciprocating engine works, and which
piston in its to and fro movements opens and closes such passages, so that when one
side of such main piston is open to exhaust, the corresponding end of the auxiliary
valve cylinder is also open to exhaust, while the opposite end of the auxiliary valve
cylinder is through the other passage open to the supply which is then acting on
the opposite side of the main piston. The auxiliary valve is thus shot over from
one end of its cylinder to the other, and in its movement shuts a passage leading
to one end of the cylinder in which the main valve works, while it opens a second
passage leading to the opposite end of the main valve. cylinder to the main
exhaust.
The construction of the main valve and the arrangement of the ports or passages
for actuating same may be similar to that set forth in the Specifications of our prior
Patents Nos. 8873 dated 9th June 1890 and 11,216 dated 18th July 1890, but the
passages connecting the ends of the main valve cylinder with the passages leading
to the, ends of the main piston cylinder will not be necessary, as the connection with
the exhaust in the present arrangement will be effected through the auxiliary valve
cylinder.
It will however be readily understood that the main valve may be constructed
and actuated in any other suitable manner instead of that described in the
Specifications of such prior Patents.
In the accompanying drawings
Fig. 1 is a longitudinal vertical section through the auxiliary valve and maiņ
cylinder of a reciprocating engine, taken on the line a, a, Fig. 4.
Fig. 2 is a central longitudinal vertical section through the main valve and main
cylinder of such engine, the main valve being arranged and actuated in the manner
set forth in the Specifications of our prior Patents above referred to.
Fig. 3 is a plan view of the face of the main cylinder.
Fig. 4 is a transverse section through the auxiliary and main valves and the
main cylinder, and
Fig. 5 a horizontal section through the auxiliary and main valves.
In these drawings A is the auxiliary valve constituting our invention, and which
works in a cylinder B, from. the opposite ends of which passages C, C1, lead to
near the opposite ends of the main cylinder D of the reciprocating engine, and are
controlled by the main piston E of such cylinder, so that when one side of such
piston is open to exhaust through the main valve (to be hereinafter described) the
corresponding end of the auxiliary valve cylinder is also open to exhaust, while
the opposite end of same will through the other passage, C or C₁, be open to the
supply which is then acting on the opposite side of the main piston E, as soon as
the latter in its travel uncovers such passage, and the auxiliary valve A will
consequently be shot over from one end of its cylinder B to the other.
As will be seen in Fig. 1, the auxiliary valve A is formed with an annular
groove A' in its centre, while ports F, F, are formed in its cylinder B and lead
respectively to the opposite ends of the main valve cylinder G, in which works the
main valve H for controlling the supply and exhaust to the main cylinder D in
which the main piston E reciprocates (see Figs. 2 and 5). The auxiliary valve
cylinder B has also another passage 1 leading to the exhaust passage J, and the,
movement of valve A in its cylinder B alternately connects such passage I with one
or other of the passages F, F', leading respectively to the opposite ends of the
main valve cylinder G, which is consequently brought open to exhaust.
In the drawing the main valve H is shown as being actuated by the movement
of the main piston E controlling a port or passage K leading to near the oppos te
ends of the main valve cylinder G, so that steam from that side of the piston E,
which is being acted upon, is at a certain point in its travel admitted to one end of

page_text: the main valve cylinder (the end of the passage K leading to the opposite end of
such main valve cylinder being at that time closed by the main valve H) and the
main valve is consequently shot over in its cylinder and reverses the connection
between the opposite sides of main piston E with steam and exhaust respectively,
through the passages L, M and exhaust J in the well known manner." It will
however be readily understood that such main valve H may be actuated in any
other suitable manner to that described.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
The combination with the main valve of reciprocating engines, of an auxiliary
valve actuated by passages leading from the opposite ends of the cylinder in which
such auxiliary valve works, respectively to near the opposite ends of the main
cylinder in which the main piston works, and which passages are controlled by the
movement of the latter, the movement of such auxiliary valve controlling other
passages leading respectively to the opposite ends of the cylinder in which the
main valve works so as to place such ends alternately in connection with an exhaust
passage, all substantially as specified.
Dated this 16th day of February 1894.
ALLISON BROS.,
Agents for the Applicants.