Improvements relating to the Blast Pipes of Locomotive and other High Pressure Engines.
Year: 1891

page_text: Date of Application, 6th Mar., 1891
Complete Specification Left, 4th Dec., 1891-Accepted, 9th Jan, 1892
PROVISIONAL
SPECIFICATION.
Improvements relating to the Blast Pipes of Locomotive and other
High Pressure Engines.
1, GEORGE MACALLAN of Earlham Grove, Forest Gate, London, Engineer, do
hereby declare the nature of this invention to be as follows:-
This invention has for its object improvements relating to the blast pipes of
locomotive and other high pressure engines.
In the Specification of a former Patent granted to me and another No. 17014 in
the year 1888 there is described a method of varying the orifice of the blast pipe
by means of a cap which can be applied and removed at pleasure. In the use of
such caps some difficulty is experienced in preventing steam from passing out
beneath the cap.
This difficulty I overcome by inserting a ring or liner into the
mouth of the blast pipe in such manner as to project from the top thereof up into
the interior of the cap. The ring or liner may be so formed as to reduce the area
of the mouth of the blast pipe where this is desirable or the mouth may be left of
its original dimensions. The ring or liner may when desired be readily removed
and replaced by another of different size.
Dated this 5th 1 of Manah 1001
G. MACALLAN.
COMPLETE SPECIFICATION.
Improvements relating to the Blast Pipes of Locomotive and other
High Pressure Engines.
I, GEORGE MACALLAN, of Earlham Grove, Forest Gate, London, Engineer,
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 has for its object improvements relating to the blast pipes of
locomotive and other high pressure engines.
In the Specification of a former Patent granted to me and another No. 17014 in
the year 1888 there is described a method of varying the orifice of the blast pipe
by means of a cap which can be applied and removed at pleasure. In the use of
such caps some difficulty is experienced in preventing steam from passing out
beneath the cap.
This difficulty I overcome by inserting a ring or liner into the
mouth of the blast pipe in such manner as to project from the top thereof up into
the interior of the cap. The ring or liner may be so formed as to reduce the
area of the mouth of the blast pipe where this is desirable or the mouth may be
left of its original dimensions. The ring or liner may when desired be readily
removed and replaced by another of different size.
In order that my said invention may be fully understood and readily carried into
effect, I will proceed to describe the drawings hereunto annexed.
Figure 1 is a vertical section, and Figure 2 is a plan.
a is the fixed pipe.
bis the movable conical cap or nozzle which I provide. I connect this cap or
nozzle with the lower part of the blast pipe by a hinge joint.
a al are lugs on the pipe a, and b is a lug on the cap.
c is a joint pin passing through the lugs. It is free to turn in the lugs a', but is
fast with the lug b¹.
d is an arm fixed on the joint pin c.
Pin G21
It is coupled to a longitudinal rod

page_text: connected to any convenient arrangement of gear moved by hand from the foot
plate of the engine.
e is a bush or liner partially inserted into and secured to the mouth of the
pipe a. This effectually prevents steam from escaping at the joint between pipe a
and cap or nozzle 6 when the said cap b is on, as shown, and it also provides a
convenient means of altering the area of the fixed outlet by substituting liners of
various diameters, as represented by the dotted lines. In this way, when desired,
the cap can be lifted from the top of the pipe a and moved out of the way
turning about the joint pin c. Again, when the engine driver desires the cap can
be replaced on the top of the pipe.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The combination of a blast pipe, a moveable cap, which when in place rests
on the top of the blast pipe, and a liner inside both the cap and the mouth of the
blast pipe and covering the joint.
2. The combination of a blast pipe, a moveable cap hinged to the blast pipe and
which when in place rests on the top edge of the pipe, and a liner inside both the
cap and the pipe and covering the joint between them.
3. The combination of a blast pipe, the lugs a' thereon, the spindle c mounted in
bearings in the lugs, the annular cap provided with the arm &¹, connected to the
spindle and arranged between the lugs a¹ and a liner e, inside both the cap and the
pipe and covering the joint between them.
Dated this 19th day of November 1891.
G. MACALLAN.