Improvements in or appertaining to the Lifting, Lowering, and Controlling the Action of Suction and Delivery Valves of Air Compressors, Gas Compressors, Blowing Engines, and Exhausting Pumps.
Year: 1893

page_text: Date of Application, 11th Dec., 1893
Complete Specification Left, 11th Oct., 1894-Accepted, 17th Nov., 1894
PROVISIONAL SPECIFICATION.
Improvements in or appertaining to the Lifting, Lowering, and
Controlling the Action of Suction and Delivery Valves of Air
Compressors, Gas Compressors, Blowing Engines, and Exhausting
Pumps.
We JOHN WEST, of Barfield House, Didsbury, and WILLIAM JOHN JENKINS,
of 340 Queens Road, Cheetham, Manchester, both in the County of Lancaster,
Engineers, do hereby declare the nature of this invention to be as follows:-
This invention relates to mechanism or apparatus for lifting, lowering, and
controlling the suction and delivery valves which are employed in the cylinders and
pump chambers of machinery for compressing or exhausting air, gases, or other
fluids; and consists essentially in applying to suction and delivery valves closing
and opening springs of such strength that one will operate the valve when the valve
is left free and the other will operate the valve against the action of the first when
otherwise free, and in taking off from the valve the force of the stronger spring and
re-applying it at the desired times.
The general practice up to the present time is to arrange these valves to lift and
lower automatically and they are generally provided with springs having a tendency
to keep the valves closed. The object of the springs is firstly to act as buffers to
prevent damage to the valves or adjacent parts from the sudden opening of the
valves in working and secondly to accelerate the closing of the valves so as to
prevent the defect known technically as "slip," that is the loss of a portion of the
air, gas, or fluid, already drawn into the cylinder by forcing it out during the first
part of the compression stroke before the valves have had time to close. The
springs on the suction valves act as a resistance to the opening of the valves, and
cause the pressure inside the cylinder during the suction stroke to be lower
than the pressure outside the cylinder. The difference in pressure acts as
resistance to the motion of the piston and thus causes a waste of power and less
weight of air, gas, or fluid is drawn into the cylinder during each stroke causing a
loss of volumetric efficiency. The springs on the delivery valves also tend to keep
the valves closed, and it is therefore necessary for the pressure inside the cylinder
during the compression stroke to be higher than that of the vessel, mains, pipes, or
atmosphere into which the air, gas, or fluid is being delivered, this excess of
pressure also acts as a resistance to the motion of the piston and causes a waste of
power.
The object of this invention is to remove the abovenamed defects and to provide
means for the more efficient working of the aforesaid machinery..
In carrying this invention into practical effect the valves are arranged in any
convenient position as near the cylinder as possible, for instance they can be placed
in the end covers, or in a valve chest connected with the cylinder. Each valve is
provided with a stem of convenient length either made solid with the valve or
attached thereto, and the stem is guided and held in position by two bored guides,
The latter
one placed near the valve and one at the opposite end of the stem.
guide is made adjustable by screwing it into or out of the casting holding it in
position. At a suitable place on the stem between the two guides, a collar or
enlargement is provided and fixed firmly to it and between this collar and the
adjustable end guide a spring is placed of such a strength that when the valve is
a

page_text: left free the spring will move the valve open to the desired amount, and when the
valve is closed the spring will be compressed and will thus have a tendency to open
the valve. Between the aforesaid collar or enlargement and the bored guide near
the valve are placed a closing spring bearing at one end against a fixed abutment
near the valve, and resting at the other end upon a loose collar or sleeve encircling
the stem but not touching it, nor attached to it in any way, the loose collar or
sleeve in its turn bears against the fixed collar or enlargement of the stem at the
opposite end to the lifting spring before described. The loose collar or sleeve is
provided with centre pins or snugs by which it can be moved under the influence of
a forked lever having a fulcrum at a convenient point and having a roller at
another point A shaft revolving at the same speed as the main shaft driving the
piston of the compressing or exhausting cylinder is provided with a cam which
comes in contact with the roller on the forked lever. The cam is made of a suitable
shape to cause the torked lever to oscillate through a small angle round the fulcrum
and when this takes place in one direction the forked lever compresses the closing
spring and keeps it compressed during a portion of a revolution then gradually
releases the spring and leaves it released for another portion of a revolution. The
closing spring is considerably stronger than the lifting spring so that when the
closing spring is released it forces the valve to close against the action of the lifting
spring.
The operation as regards the suction valves is as follows:-
Shortly before the piston arrives at the end of a compression stroke the cam is
set to move the forked lever, and with it the loose collar or sleeve in the direction
which compresses the strong closing spring sufficiently to allow of the desired lift.
The lifting spring is then free to open the valve as soon as the pressure due to the
compression stroke is removed. The spring is exerting some force tending to open
the valve, and shortly after the piston begins its return or suction stroke the
pressure falls sufficiently and the spring forces the valve full open, that is until the
fixed collar or enlargement on the stem again comes in contact with the loose collar
or sleeve.
The continued rotation of the cam keeps the closing spring compressed to the
same degree until the piston approaches within a short distance of the end of its
return or suction stroke when the cam gradually allows the closing spring to
expand and gradually close the valve against the action of the lifting spring until
the valve rests on its seat immediately before the end of the stroke. The cam is
of such a shape that for nearly half a revolution it does not again come in contact
with the roller but when it does the same cycle of operation takes place.
The operation as regards the delivery valves is substantially the same as that now
described for the suction valves, but it is generally necessary to provide a stuffing box
and gland between the two bored guides, and the springs have to be stronger in
consequence of the extra friction and heavier pressure. In exhausting apparatus it
is sometimes necessary to provide a gland and stuffing box on the suction valves as
well, and the springs are then to be proportioned accordingly.
Two or more suction valves, or delivery valves for the same end of the cylinder
can be worked by one cam respectively by arranging a yoke to take the place of
the loose collar or sleeve, and attaching the forked lever to the centre of the yoke,
so that all the closing springs may be operated at the same time.
This invention is equally suitable to either vertical or horizontal arrangements of
the compressing or exhausting cylinders.
Dated this 11th day of December 1893.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in or appertaining to the Lifting, Lowering, and
Controlling the Action of Suction and Delivery Valves of Air
Compressors, Gas Compressors, Blowing Engines, and Exhausting
Pumps.
We JOHN WEST, of Barfield House, Didsbury, and WILLIAM JOHN JENKINS,
of 340 Queens Road, Cheetham, Manchester, both in the County of Lancaster,
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 :-
This invention relates to mechanism or apparatus for lifting lowering and
controlling the suction and delivery valves which are employed in the cylinders and
pump chambers of machinery for compressing or exhausting, air, gases, or other
fluids, and consists essentially in applying to suction and delivery valves closing
and opening springs of such strength that one will operate the valve when the valve
is left free and the other will operate the valve against the action of the first when
otherwise free, and in taking off from the valve the force of the stronger spring and
reapplying it at the desired times.
The general practice up to the present time is to arrange these valves to lift and
lower automatically, and they are generally provided with springs having a tendency
to keep the valves closed. The object of the springs is firstly to act as buffers to
prevent damage to the valves or adjacent parts from the sudden opening of the
valves in working and secondly to accelerate the closing of the valves so as to
prevent the defect known technically as "slip," that is the loss of a portion of the
air, gas, or fluid already drawn into the cylinder by forcing it out during the first
part of the compression stroke before the valves have had time to close. The
springs on the suction valves act as a resistance to the opening of the valves, and
cause the pressure inside the cylinder during the suction stroke to be lower than
the pressure outside the cylinder. The difference in pressure acts as a resistance to
the motion of the piston and thus causes a waste of power and less weight of the
air, gas, or fluid is drawn into the cylinder during each stroke causing a loss of
volumetric efficiency. The springs on the delivery valves also tend to keep the
valves closed, and it is therefore necessary for the pressure inside the cylinder during
the compression stroke to be higher than that of the vessel, mains, pipes or
atmosphere into which the air, gas, or fluid is being delivered; this excess of
pressure also acts as a resistance to the motion of the piston and causes a waste of
power.
The object of this invention is to remove the above named defects and to provide
nieans for the more efficient working of the aforesaid machinery.
In carrying this invention into practical effect the valves are arranged in any
convenient position as near the cylinder as possible, for instance they can be placed
in the end covers, or in a valve chest connected with the cylinder. Each valve is
provided with a stem of convenient length either made solid with the valve or
attached thereto, and the stem is guided aud held in position by two bored guides,
one placed near the valve and one at the opposite end of the stem. The latter
guide is made adjustable by screwing it into or out of the casting holding it in
position. At a suitable place on the stem between the two guides, a collar or
enlargement is provided and fixed firmly to it and between this collar and the
adjustable end guide a spring is placed of such a strength that when the valve is
left free the spring will move the valve open to the desired amount, and when the
valve is closed the spring will be more compressed and will thus have a tendency to
open the valve. Between the aforesaid collar or enlargement and the bored guide

page_text: near the valve is placed a closing spring bearing at one end against a fixed
abutment near the valve, and resting at the other end upon a loose collar or sleeve
encircling the stem but not touching it, nor attached to it in any way; the loose
collar or sleeve in its turn bears against the fixed collar or enlargement of the stem
at the opposite end to the lifting spring before described. The loose collar or
sleeve is provided with centre pins or snugs by which it can be moved under the
influence of a forked lever having a fulcrum at a convenient point and having a
roller at another point. A shaft revolving at the same speed as the main shaft
driving the piston of the compressing or exhausting cylinder is provided with a
cam which comes into contact with the roller on the forked lever. The cam is made
of a suitable shape to cause the forked lever to oscillate through a small angle round
the fulcrum and when this takes place in one direction the forked lever compresses
the closing spring and keeps it compressed during a portion of a revolution then
gradually releases the spring and leaves it released for another portion of a
revolution. The closing spring is considerably stronger than the lifting spring so
that when the closing spring is released it forces the valve to close against the
action of the lifting spring.
The operation as regards the suction valves is as follows:-Shortly before the
piston arrives at the end of a compression stroke the cam is set to move the forked
lever, and with it the loose coilar or sleeve in the direction which compresses the
strong closing spring sufficiently to allow of the desired lift. The lifting spring is
then free to open the valve as soon as the pressure due to the compression stroke is
removed the spring is exerting some force tending to open the valve, and shortly
after the piston begins its return or suction stroke the pressure falls sufficiently and
the spring forces the valve full open, that is until the fixed collar or enlargement on
the stem again comes in contact with the loose collar or sleeve.
The continued rotation of the cam keeps the closing spring compressed to the
same degree until the piston approaches within a short distance of the end of its
return or suction stroke when the cam gradually allows the closing spring to
expand and gradually close the valve against the action of the lifting spring until
the valve rests on its seat immediately before the end of its stroke. The cam
is of such a shape that for nearly half a revolution it does not again come in
contact with the roller but when it does the same cycle of operation takes place.
The operation as regards the delivery valves is substantially the same as that now
described for the suction valves, but it is generally necessary to provide a stuffing
box and gland between the two bored guides, and the springs have to be stronger
in consequence of the extra friction and heavier pressure. In exhausting apparatus
it is sometimes necessary to provide a gland and stuffing box on the suction valves
as well, and the springs are then proportioned accordingly.
Two or more suction valves, or delivery valves for the same end of the cylinder
can be worked by one cam respectively by arranging a yoke to take the place of
the loose collar or sleeve, and attaching the forked lever to the centre of the yoke,
so that all the closing springs may be operated at the same time.
This invention equally suitable to either vertical or horizontal arrangements
of the compressing or exhausting cylinders.
In order that this invention may be more readily understood and more easily
carried into effect we will proceed to describe the same with reference to the
accompanying drawings in which we show various arrangements as follows:-
Fig. 1 is a sectional elevation through the centre of the suction and delivery
valves when arranged to act vertically in the end cover of a horizontal compressing
cylinder and Fig. 2 is a side sectional elevation on the line X-Y, the valves and
parts being shown in the positions they would occupy when the piston had just
reached the limit of its stroke furthest from the end cover shown, that is it would
just have completed a suction stroke.
Fig. 3 is an end elevation of the suction and delivery valves when arranged to
act horizontally in the end cover of a horizontal compressing cylinder, and Fig. 4
is a side sectional elevation on the line W-Z the valves and parts being shown in

page_text: the positions they would occupy when the piston was just beginning its suction
stroke.
Fig. 5 is an end elevation partly in section showing the arrangement of two
suction valves acting vertically in the end cover of a horizontal compressing
cylinder.
Fig. 6 is a side sectional elevation on the line 1-2 the valves and parts being
shown in the positions they would occupy when the piston was performing its
suction stroke.
•
Fig. 7 is a plan of the yoke arranged for working the two suction valves from
one cam.
:
Fig. 8 is a sectional elevation through the end cover of a vertical compressing
cylinder showing the arrangement for working the suction and delivery valves
vertically. Fig. 9 is a plan of the same partly in section. Fig. 10 is an elevation
of the arrangement shown by Fig. 8, the valves and parts being shown in the positions
they would occupy when the piston was performing its delivery stroke.
Fig. 11 is a sectional elevation through the centre of the suction valves of a
horizontal exhausting cylinder showing the suction valves acting vertically. Fig. 12
is a side sectional view of the same, the valves and parts being shown in the
positions they would occupy when the piston was performing its suction stroke.
Fig. 13 is an end elevation similar to Fig. 5 showing one suction valve only
worked by the cams.
· Referring to the figures, the suction valves a a situated in the end cover d of the
cylinder are provided with stems ee working in the bored guides bb, bb the
guides marked 'being adjustable by means of the screw thread cut on the outside
of them and working in the nuts ff which are fixed in brackets cast with the covers
or fixed thereto. The collars or enlargements y y are fixed firmly to the stems by
meaus of the cotters / h. The lifting springs i encircle the stems e e and bear
against the collars y g and nuts. The closing springs kk bearing at one end
against fixed abutments rest at the other end upon loose collars or sleeves min
encircling the stems e e but not touching them nor attached to them in any way.
The loose collars or sleeves are in this instance yoked together for convenience of
working two valves from one cam and the yoke m can be moved under the influence
of a forked lever n having a fulcrum o at a convenient point and a roller p at
another convenient point. A shaft 9 revolving at the same speed as the shaft
driving the piston of the compressing cylinder is provided with a cam
c which
comes into contact with the roller p on the forked lever n. The came is made of
suitable shape to cause the forked lever n to oscillate through a small angle round
the fulcrum o aud when this takes place in one direction the forked lever n acting
upon the loose collar or yoke m compresses the closing spring k and keeps it
compressed during a portion of a revolution, then gradually releases the spring k
by the sloping shaper of the cam c. and leaves it released for another portion of a
revolution.
The operation as regards the suction valves is as follows:-Shortly before the
piston arrives at the end of a compression stroke the cam C is set to move the forked
lever n and with it the loose collar sleeve or yoke m in the direction which
compresses the strong closing spring k sufficiently to allow of the desired lift. A
space then exists between the loose collar sleeve or yoke. m and the collar or.
enlargement g on the stem e, this space being the amount of the desired lift-this
position is more clearly shown by Fig. 4 which shews the position of the valves and
parts at the moment when the piston is about to begin its return or suction stroke.
The lifting spring i is of such a strength that it has just sufficient upward force to
bear the weight of the valve a with its stem e and collar y when the valve a is
lifted its full amount consequently the spring i being compressed has a tendency to
open the valve a as soon as the closing spring k has been compressed but owing to
the pressure left in the cylinder from the compression stroke the spring i has not
sufficient force to lift the valve a until the piston has moved back a slight distance
depending upon the clearance space and has thus reduced the pressure to an amount

page_text: equal to that outside the cylinder. The spring i owing to its compression has a
tendency to open the valve and immediately the pressure falls as just described the
spring acts and forces the valve at once to its full height of lift and holds it there
until by the continued rotation of the shaft g the cam c releases the strong closing
spring and gradually forces the valve a down to its seat against the action of the
weaker opening spring i.
The delivery valves A A are provided with stems E E working in bored
guides B B. The lifting springs II are supported by the adjustable plates F F.
The collars G G or enlargements are fixed firmly to the stems E E by means of
the cotters H H. The closing springs K K bearing at one end against fixed
abutments L L rest at the other end upon the loose collars sleeves or yokes M M
encircling the stems E E but not touching them nor attached to them in any way.
The loose collars or sleeves are yoked together for convenience of working two
valves from one cam and the yoke can be moved under the influence of a forked
lever N having a fulcrum O at a convenient point and connected at one end by
means of a rod T to another lever U provided at one end with a roller P and
moving at the other round a fulcrum O. It will be understood that the lever U
with its roller P is side by side with the lever n and its roller p. To prevent the
escape of air, gas, or other fluid body from the space V the stems E E pass through
stuffing boxes S S which may be packed with metallic packing as shown or with
fibrous packing of the usual kind. The lifting springs II are made stronger for the
delivery valves on account of having to overcome the friction of the stems E E in
the packing S S. The method of working is the same as described for the suction
valves only that the cam C is timed to come into operation to suit the delivery
stroke.
Although the valves are shown in one cover only of the cylinder it is to be under-
stood that all that applies to one end of a cylinder also applies to the other and the
mechanism would be arranged in a similar manner. It is not necessary to apply
these valves exclusively to the covers of the compressing or exhausting cylinders
though that arrangement has been shown because it is generally the most
convenient; but the valves, controlled in the manner described in this Specification
will act equally well whether placed in the covers or in separate valve chests in any
convenient position.
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 :-
1. In compressing or exhausting apparatus a valve mechanism for an automatic
suction or delivery valve consisting of two opposing springs of different strengths
acting on the valve and of mechanism actuated automatically and operating. to
relieve the valve from the action of the stronger spring at the desired times
substantially as described.
2. In compressing or exhausting apparatus, a valve mechanism for an automatic
suction or delivery valve consisting of two opposing springs of different strengths
acting on the valve, of a lever adapted to take the pressure of the stronger spring,
and of a cam fixed on a revolving shaft of the apparatus and actuating the said
lever so as to cause it to take the pressure of the said stronger spring at the desired
times, substantially as described.
3. The general arrangement and combination of the parts for controlling the
action of suction and delivery valves substantially as hereinbefore described and
shown in the annexed drawings.
Dated this 11th day of October 1894
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.