IMPROVE- MENTS IN AND CONNECTED WITH VALVES FOR BLOWING AND AIR-COMPRESSING ENGINES
Year: 1875

page_text: LETTERS PATENT to John Thomson King, of Liverpool, in the
County of Lancaster, Patent Agent, for the Invention of "IMPROVE-
MENTS IN AND CONNECTED WITH VALVES FOR BLOWING AND AIR-COMPRESSING
ENGINES." A communication from abroad by Wilson Black Chis-
holm, of Cleveland, Ohio, United States of America, Manufacturer.
Sealed the 9th December 1875, and dated the 21st September 1875.
PROVISIONAL SPECIFICATION left by the said John Thomson
King at the Office of the Commissioners of Patents, with his
Petition, on the 21st September 1875.
I, JOHN THOMSON KING, of Liverpool, in the County of Lancaster,
Patent Agent, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN AND CONNECTED WITH VALVES FOR BLOWING AND AIR-
COMPRESSING ENGINES," to be as follows:-
:-
This Invention relates to the valves and to the combination of valves
with air ports, passages, and valve connections of blowing or pumping
engines; the valves are of the annular class. Heretofore annular valves

page_text: have ordinarily been formed of an endless india-rubber or gutta percha
band operating over an annular series of air ports. An annular valve
arranged as above mentioned operates by its own elasticity with or
without exterior air pressure to close the ports, the opening of such
ports-being-effected by interior air pressure acting so as to distend the E
annular valve. The heat evolved in the compression-of air is_so_great_
as to act injuriously on the india-rubber or gutta percha band forming
the valve, thereby causing such valve to lose its cohesion and become
brittle, so as to render such valve liable to tear or break, thus necessitating
frequent renewals. Now my Invention consists in constructing an 1
annular valve, which shall be free from the disadvantages above
described. For this purpose I construct an annular valve of a ring of
metal cut through the circumference at one part and lined with -india-
rubber, leather, or like material.
The india-rubber or other lining may be secured to the metal ring in 1
any convenient manner, such as by rivetting.
The said lining may also be in a continuous piece, or may preferably
be attached in lengths.
By the above arrangement, if the india-rubber or other lining becomes
more or less brittle, such lining is kept in its place, and fit for work by 2
its adhesion to the metal ring above mentioned. The metal band, and
with it the lining, is held in position by guide pieces or bearers.
Annular valves constructed as above described are fitted externally
round the air suction and eduction ways.

page_text: The same letters indicate like parts.
The air blowing or compressing cylinder B is made of the usual or
any desired form. The end plate or head B¹ is made with suitable air
ports b for the inflow of air into the chamber A, or with a trunk or 30
passage P for supplying air from such point at a distance as will secure

page_text: the exclusion of dust, dirt, etc., in injurious or objectionable quantities.
From the trunk P the ports p open into the chamber A. This chamber
is closed at its cylinder end by a diaphragm q, and the outer edge of the
latter is connected to the head B¹ by a cylindrical ring R, in which is a
series of air ports a for the ingress of air. In the cylinder case at r, and
at or near the end of the cylinder B, is a like annular series of ports c
for the egress of air, which latter then entering an annular chamber n
is conducted by a trunk passage m and a trunk pipe connected at m¹ to
the receiver or place of storage or use. D is the usual piston or plunger
with a stem d playing through a stuffing box d³, which is to be suitably
packed in any known way.
My improved valve is composed of a strip of india-rubber or
caoutchouc S of a length and width equal, or about equal, to the cir-
cumference and breadth of the ring R or r, in which the air ports a or c
are made, and which ports it is designed to open and close. On the
outside or outer face of this india-rubber I rivet a strip of spring steel S¹
of corresponding length and width and previously bent and tempered,
so as to assume and preserve a circular or nearly circular form, and by
its own elasticity tightly encircle, encompass, or clasp the air-port
rings R, r, on which rings the valves are arranged, so that each shall be
in position to close and open its own system or arrangement of ports.
A considerable number of rivets should be inserted, so that even if the
rubber should become partially disintegrated by the action of the heat
thereon the rivets will still hold all or most of the broken pieces in
place. At the same time the tension or strain which in the old con-
struction was wholly on the india-rubber band is now transferred to the
steel, so that the india-rubber is much less liable to break or to become
disintegrated than when the steel was not used. These band valves (as
I term them for convenience) made of combined india-rubber and steel
are applied to the air inlet and outlet ports a and c, one on each set of
ports, so as to cover the same on the outside and be lifted therefrom by
interior air pressure. They are steadied in place by means of lugs e,
which are secured to the valves with an eye or hole in each lug passing
over a pin e¹, and by the ribs wo on the inside of the cylinder B, and
along the inner edge of the outer valve.
Other suitable devices may be employed for securing the valves
nananly in place and cuiding them in their movement

page_text: The operation is as follows:-With a stroke of the piston D to the
right the band valve on will be seated by the elasticity of the steel,
either with or without the co-operation of back air pressure, so as to cut
off all back-flow-of air from the reservoir or intermediate passages.
Also the valve on R will be raised for the entrance and inflow and
supply of air into and through chamber A and ports a, and thence into
the cylinder B. With a reverse stroke of the piston D the band valve
on R will be seated by back pressure, and the elasticity of the steel,
either or both, and the band valve on r will be raised by interior air
pressure acting through the ports c, so as to uncover or open such ports
for the egress of the air thus compressed to the reservoir as already
described. The yielding elastic or pliable face of the rubber strip S
coming on the ports a or c effectually closes them when the band valves
are seated, and the metallic spring backing of the band valves yields
sufficiently to lift the rubber face from the ports at the proper time, but
such metallic spring backing not being to any practical extent affected
by the heat reseats by its own elasticity the rubber lining; but it is not
essential that the yielding face S should be made in one piece, as it
may be made of separate pieces, each rivetted along its edges to the
metallic spring backing, and at intermediate points of its body if it be
of considerable size; and instead of india-rubber other like suitable
flexible and pliable material may be employed, and any metal possessing
in band form the desired elasticity may be substituted for the steel
spring as the mechanical equivalent thereof.

page_text: Third. The band valve described in combination with an annular
series of air ports for the ingress or egress of air in air-compressing or
blowing operations, substantially as set forth..
In witness whereof, I, the said John Thomson King, have here-
unto set my hand and seal, the Sixteenth day of March, in
the year of our Lord One thousand eight hundred and seventy-
six.