Improvements in or relating to Valve Mechanism, applicable for Apparatus for Compressing Air and Gases, or for other purposes.
Year: 1895

page_text: Date of Application, 26th Jan., 1895
Complete Specification Left, 28th Oct., 1895-Accepted, 30th Nov., 1895
PROVISIONAL SPECIFICATION.
Improvements in or relating to Valve Mechanism, applicable for
Apparatus for Compressing Air and Gases, or for other
purposes.
We, JOHN SCARISBRICK WALKER, THOMAS ASCROFT WALKER and EDWIN
ROBERT WALKER, all of Pagefield Iron Works, Wigan in the County of
Lancaster, Engineers do hereby declare the nature of this invention to be as
follows:-
This invention relates to valve mechanism especially for engines for compressing
air and gases, though it may be otherwise applied, and one of the objects of our
invention (inter alia) is to ensure the smooth operation of the valves to prevent
them chattering, and generally to regulate their movements.
In carrying our invention into effect, the valves we prefer to use are a form of
hinged valves which may be carried upon their own bearings or trunnions, or may
have a spindle or its equivalent passing through them or they may be otherwise
arranged. These valves are so balanced as to reduce the blows caused by the
pulsating action of the air when the compressor is at work. The balancing may be
effected in numerous ways and we do not confine ourselves to any special arrange-
ment. The simplest plan is to apply a counterweight direct to the valve, in such a
manner that the counterweight shall be on one side of the trunnion and the valve
on the other. The counterweight however may be arranged on a separate lever
coupled by a series of levers or links to the valve or in any other suitable manner.
The counterweight may be arranged to counterbalance the valve exactly, or weigh
against it with a greater or less weight or power, and we reserve to ourselves the
right of making this counterweight adjustable, so that its effect on the valve can be
varied at will, even while the engine is at work. This adjustment can be obtained
in a variety of ways, such as making the counterweight movable and providing a
series of levers or the like which enable the weight to be shifted while the engine
is at rest or in motion, but we do not confine ourselves to this arrangement, the
object being to adjust the counterweight so that it and the valve can be placed in
exact equilibrium, or that one may weigh against the other with a greater or less
weight according to requirements.
To further regulate the moving of the valves, we provide a suitable friction or
brake device by which a certain brake resistance or absence of freedom can be
imparted to the valve, which is thus prevented from chattering and caused to move
smoothly throughout its course, besides being adaptable to the varying conditions
of speed and pressure. The valves may be furthermore controlled by springs or
cushioning devices which will act to a considerable extent to buffer the valve as it
approaches its seat, also by springs which are arranged to help it off its seat again
when the piston moves upon its return stroke.
The details of the braking or friction device aforesaid may be very considerably
varied without departing from the principle of our invention, but an arrangement
which gives good results consists of a shoe or block adapted to press on the counter-
weight or some other part connected directly or indirectly with the valve, a spring
or its equivalent, and a screw or equivalent for applying and regulating the pressure

page_text: exerted by the spring and brake shoe upon the counterweight, and thus by this
means the brake resistance on the valve can be varied at will, even whilst the
engine is at work. Any other means, however, may be employed for moving the
bråke device so as to increase and decrease the pressure and braking effect.
In order to give accessibility to the valves and allow them to be easily removed
without taking off the compressor cylinder cover, we propose to form in the cover
of the cylinder an opening sufficiently large for the valves to pass, through.
This opening is closed by a suitable lid or bonnet, which may be bolted or
otherwise securely fastened on. The openings for the valves are formed in any
suitable part, and when upon their seats the valves preferably haug vertically
downwards so that their backs lie flat in a vertical plane, whereby the piston can
be moved to the end of its stroke against the valve. The space between the piston
and the valve can be accurately gauged by looking through the opening aforesaid,
and the attendant can look straight between the valve and piston. and thus
absolutely see what clearance there is, also if necessary the effect of working can
be seen by this means.
The buffering arrangement may be similar to that described in. our previous
Patent No. 10356 of 1894, or any other arrangement may be used. having. sufficient
resiliency or compression to check the valve as it approaches its seat, but never-
theless allow it to fully bear upon its seat when the pressure comes upon it.
By a buffering arrangement of this kind the valve is prevented from banging onto
its seat, but nevertheless is allowed to sit fairly upon it.
This buffering device in conjunction with the brake device, the device for
helping the valve off its seat, and the arrangement whereby the valve is balanced
so as to be in equilibrium is found to control the valves in every respect allowing
them additional freedom and delicacy of movement, while at the same time
preventing chattering or sudden jar, and enabling them automatically to
accommodate themselves to the variations in speed or pressure due to the working
conditions, or the accommodation can be promptly provided by the attendant:
adjusting the devices provided for the purpose.
The valve trunnions to which reference has already been made, work by
preference in suitable bushes or sleeves which are mounted in an outer shell or
frame. These bushes or sleeves are closed at the outer ends so that dust etcetera
cannot find its way into the bearings, to injure the delicacy of movement of the
valves. A shoulder on the outside of the sleeves which abuts against the shells,
keeps the sleeves in place, and the lubrication is effected by a lubricator of any
suitable kind.
We have described one way in which our invention as applied to air compressors
may be carried into effect, but it is obvious that having once given the idea,
alterations may be made without departing from the principle of our invention:
Moreover our idea may be applied with equal advantage to compressors for gases
and for various other purposes, in which case alterations may have to be made.in
the construction to suit special requirements.
The present invention may be used in conjunction with any of the devices or
arrangements set forth in our previous Specification No. 10,356 of 1894 if so
desired.
Dated this 25th day of January 1895

page_text: COMPLETE SPECIFICATION.
Improvements in or relating to Valve Mechanism, applicable for
Apparatus for Compressing Air and Gases, or for other
purposes.
We, JOHN SCARISBRICK WALKER, THOMAS ASCROFT WALKER and EDWIN
ROBERT WALKER all of Pagefield Iron Works, Wigan 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 valve mechanism especially for engines for compressing
air and gases, though it may be otherwise applied, and one of the objects of our
invention (inter alia) is to ensure the smooth operation of the valves to prevent
them chattering, and generally to regulate their movements.
The invention will be understood from the following description, reference being
had to the accompanying drawings, in which,
Figure 1 is a general sectional view of a portion of an air compressing cylinder,
the inlet and outlet valves, and the mechanism connected therewith ;
Figure 2 a front elevation, a small portion thereof being in section;
Figure 3 a part side elevation and part sectional view of a slightly modified
arrangement;
Figure 4, an end elevation thereof.
ways,
A B is the cylinder cover forming a chest for the inlet valve C and outlet
valve D. The valves we prefer to use are in the form of hinged valves, which
may be carried on their own bearings or trunnions a or may have a spiudle or its
equivalent passing through them, or they may be otherwise arranged. These valves C
and D are so balanced as to reduce the blows caused by the pulsating action of the
air when the compressor is at work. The balancing may be effected in numerous
and we do not confine ourselves to any special arrangement. The simplest
plan is to apply a counterweight E direct to the valves C and D inside the valve
chest (vide Figures 1 & 2) in such a manner that the counterweights E shall be
on one side of the trunnion a and the valve on the other. The counterweights E,
however, may be arranged on a separate lever F, as shown in Figures 3 and 4.
The counterweight may be arranged to counterbalance the valve exactly, or weigh
against it with a greater or less weight or power, and we reserve to ourselves the
right of making this counterweight adjustable on the lever F so that its effect on
the valve can be varied at will. This adjustment can be obtained in a variety of
ways, such as making the counterweight movable on the lever F, or even providing
a series of levers or the like operated by a handle, which enable the weight to be
shifted while the engine is at work or in motion, but we do not confine ourselves
to any exact arrangement, the object being to adjust the counterweight so that it
and the valve can be placed in exact equilibrium, or that one may weigh against
the other with a greater or less weight according to requirements.
To further regulate the moving of the valves, we provide a suitable friction or
brake device by which a certain brake resistance or absence of freedom can be
imparted to the valve, which is thus prevented from chattering and caused to move
smoothly throughout its course, besides being adaptable to the varying conditions
of speed and pressure. The valves may be furthermore controlled by springs or
cushioning devices which will act to a considerable extent to buffer the valve as it
approaches its seat, also by springs which are arranged to help it off its seat again
when the piston moves upon its return stroke.
}
The details of the braking or friction device aforesaid may be very considerably
varied without departing from the principle of our invention, but an arrangement

page_text: t
which gives good results, consists of a shoe or block G adapted to press on the
counterweights or some other part connected either directly or indirectly with the
valves C and D, a spring H or its equivalent, and a screw I or equivalent for
applying and regulating the pressure exerted by the spring H and brake shoe G
upon the counterweight E, and thus by this means the brake resistance on the
valve can be varied at will even whilst the engine is at work. Any other suitable
means, however, may be employed for removing the brake device so as to increase
and decrease the pressure and braking effect.
In order to give accessibility to the valves C and D and to allow them to be
easily removed without taking off the compressing cylinder cover A B, we propose
to form in the cover of the cylinder, openings sufficiently large for the valves to
pass through, as more particularly described in the Specification of our prior
Patent No. 10356 dated May 28, 1894. These openings are closed by suitable lids
or bonnets F1 which may be bolted or otherwise securely fastened on. The
openings for the valves are formed in any suitable part, and when upon their seats
the valves preferably hang vertically downwards, so that their backs lie flat in a
vertical plane, whereby the piston can be moved to the end of its stroke against
the valve. The space between the piston and the valve can be accurately gauged by
looking through the opening aforesaid, and the attendant can look straight between
the valve and piston and thus absolutely see what clearance there is, also if
necessary the effect of working can be seen by this means.
The buffering arrangement may be similar to that described in our previous
Patent No. 10356 of 1894, or any other arrangement may be used having sufficient
resiliency or compression to check the valve as it approaches its seat, but never-
theless allow it to fully bear upon its seat when the pressure comes upon it. By a
buffering arrangement of this kind the valve is prevented from banging onto its
seat, but nevertheless is allowed to sit fairly upon it.
This buffering device in conjunction with the brake device, the device for helping
the valve off its seat, and the arrangement whereby the valve is balanced so as to
be in equilibrium is found to control the valves in every respect, allowing them
additional freedom and delicacy of movement, while at the same time preventing
chattering or sudden jar, and enabling them automatically to accommodate them-
selves to the variations in speed or pressure due to the working conditions, or the
accommodation can be promptly provided by the attendant adjusting the devices
provided for the purpose.
?
The valve trunnions a, to which reference has already been made, work by
preference in suitable bushes or sleeves K which are mounted in a socket L in
the cylinder covers A B. These bushes or sleeves K are closed at the outer end
so that dust, etcetera, cannot find its way into the bearings to injure the delicacy of
movement of the valves. A shoulder on the outside of the sleeve K which abuts
against the socket L keeps the sleeves in place, and the lubrication is effected by a
lubricator of any suitable kind.
!
We have described one way in which our invention as applied to air compressors
may be carried into effect, but it is obvious that having once given the idea,
alterations may be made without departing from the principle of our invention.
Moreover our idea may be applied with equal advantage to compressors for gases
and for various other purposes, in which case alterations may have to be made iu
the construction to suit special requirements.
The present invention may be used in conjunction with any of the devices or
arrangements set forth in our previous Specification No. 10,356 of 1894 if so
desired.
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. The improvement in or connected with engines for compressing air and gases
or the like, namely counterbalancing the valves thereof by means of counter-weights

page_text: or their equivalent, said counterweights or their equivalent being so arranged as
to counterbalance the valves exactly or weigh against them with a greater or less
weight or power for the purpose set forth.
2. In engines for compressing air and gases or the like, the arrangement for
balancing the valves so as to reduce the blows caused by the pulsating action of
the air when the compressor is at work, namely forming or providing the valves
with counterbalance weights, said weights being applied either direct to the valve
or arranged on a separate lever or levers and capable or not of adjustment
substantially as described.
3. In apparatus for balancing the valves of air compressing engines or the like,
the mechanism for imparting a brake resistance or absence of freedom to the valves
and regulating this resistance, substantially as described.
4. The general combined arrangement or construction of parts forming our.
improved apparatus for ensuring the smooth operation of the valves substantially
as set forth, in so far as it differs from our former invention set forth in our prior
Patent aforesaid.
Dated this 26th day of October 1895
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Birmingham, and London, Patent Agents.