An Improvement in the Valve Gear of Steam Engines.
Year: 1893

page_text: Date of Application, 12th June, 1893
Complete Specification Left, 2nd Dec., 1593-Accepted, 17th Mar., 1894
PROVISIONAL SPECIFICATION.
An Improvement in the Valve Gear of Steam Engines.
ERNEST EDWIN BAGULEY Engineer Lyndhurst Rowley Park Stafford do
hereby declare the nature of this invention to be as follows :-
The lap plus lead motion of the valve is obtained by having a radius link which
is attached to the end of a lever the other end of which is driven like a pendulum
by a valve connecting rod which derives its motion from the crank pin or any point
on the connecting rod of the engine. The link is held in position by a rod which is
also attached to the valve connecting rod. The port opening and cut off are
obtained by the same rod the length of which is such as to have the error due to
its end travelling in an arc corrected by the same movement of the end of the lever
which gives the lap plus lead motion. The vibration of the valve connecting rod
cause the link to swing on either side of its centre by the rod which holds the radius
link in position during the lap and lead movement. The reversing of the engine is
obtained by changing the position of the end of the intermediate valve rod by sliding
it to one or other side of the radius link centre, the length of the intermediate
valve rod being equal to the radius of the link.
Dated this Tenth day of June 1893.
COMPLETE SPECIFICATION.
An Improvement in the Valve Gear of Steam Engines.
ERNEST EDWIN BAGULEY Lyndhurst Rowley Park Stafford 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:
The lap plus lead motion of the valve is obtained by having a radius link A which
is attached to the end of a lever B the other end of which is driven like a pendulum
by a valve connecting rod C which derives its motion from the crank pin D or any
point on the engine connecting rod. The radius link A is held in position by a rod E
the length of which is such as to have the error due to its end travelling in an arc
corrected by the same movement of the end of the lever B which gives the lap and
lead movement. The vibration of the valve connecting rod C causes the radius
link A to swing on either side of its centre H by the rod E which holds the radius
link A in position during the lap and lead movement. The radius link A is carried
by centre pins H which work in the ends of the lever B in bearings H³ Fig. 3. The
lever B is carried and swings in brackets K which are attached to the framing of
the engine. The centre or fulcrum of the lever B is at I which is the centre of the
brackets which carry the lever B. The centre pins H being out of centre act as
the short end of the lever B and move the radius link from side to side of the
centre I so as to always open the valve for lead at either end of the stroke of the
engine or when the engine crank pin is on the dead centre.
Fig. 1 shows the gear with the crank pin on the dead centre at the end of the
stroke of the engine and the valve would then be open for lead. The crank p.u D
travelling in a circle moves the valve connecting rod up and down as well as
longitudinally, the up and down movement swings the radius link the same by the
rod E and thus gives the port opening & cut off.

page_text: The lever B acting with centre I as a fulcrum in the brackets K moves the radius
link A from one side of the centre I to the other and thus gives the lead at either
end of the stroke of the engine. The link A being held by the rod E is always in
the same position when the crank pin D is on either dead centre of the engine this
allows the intermediate valve rod F to be moved up and down the radius link A
without moving the valve thus giving constant lead.
Figure 2 is a section through the radius link A and one of the brackets K which
carry the lever B and in which the lever B swings. The centre pins H are part of
the bracket L which is attached to the radius link A so that the centres of the pins H
may be exactly in the centre line of the radius link A. The radius link A being
thus held when the intermediate valve rod F is moved to the middle of the radius
link A it only opens the valve to lead no matter how much the radius link A is
swung on either side of its centre by the rod E. Figure 3 shows the lever B
with bearings H' for the centre pins H to work in.
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 use of a rod (or rods) which derives its motion from the crank pin or
connecting rod of the engine and which by its horizontal movement gives motion to
a lever to get the lap and lead and by its vertical vibration gives the port opening
& cut off.
2. The oscillation of the radius link by a rod which derives its motion from the
same rod that drives the lever which gives the lap and lead movement and utilizing
the arc travelled by the lap and lead lever to correct the movement of the rod
which gives the port opening and cut off.
Dated this 30th day of November 1893.
ERNEST EDWIN BAGULEY.