An Improved Compressed Air Engine for Working Shears, and other like purposes.
Year: 1891

page_text: Date of Application, 24th Oct., 189!
Complete Specification Left. 16 h Mar., 1892-Accepted, 2nd July, 1892.
PROVISIONAL SPECIFICATION.
An Improved Compressed Air Engine for Working Shears, and other
like purposes.
We, JOSEPH FLETCHER of 111 Dolobran Road Sparkbrook Birmingham and
FREDERICK HUGGINS and HENRY HUGGINS both of the Britannia Tube Works,
Glover Street, Birmingham, Tube Manufacturers do hereby declare the nature of
this invention to be as follows:-
Our invention relates to an improved compressed air engine hereinafter described
for working shears, for shearing cattle, sheep and horses, it is also applicable for
cutting human hair and other like purposes.
Our invention consists principally in the construction and arrangement of an
engine for working the mechanism commonly used for shearing purposes, the motive
power of the said engine will be preferably compressed air, or we may employ hot
air or steam for the same purpose.
In carrying our said invention into practice, we construct a small cylinder into
which we fit a piston about five sixths the length of the cylinder, consisting of three
or more longitudinal chambers.
The upper chamber or the one nearest the inlet passage constitutes an air
chamber, for receiving the compressed air, and is provided with inlet ports or air
passages at one end, the lower chamber constitutes the exhaust or outlet.
The middle chamber which is cylindrical constitutes a valve box into which we
fit a plunger-valve a little longer than the said box, which is provided with packing
rings to insure an air tight fit.
The said valve having at each upper end ports or air passages corresponding to
the aforesaid ports in the air chamber.
At each end of the said plunger valve we form an annular opening, which is also
provided with ports or air passages constituting the exhaust port, and is connected
to similar ports formed in the lower or exhaust chamber.
Through the middle of the said plunger valve we form a slot into which
we fit a pin the function of which is to regulate the stroke of the valve.
Two or more of the aforesaid packing rings on the plunger valve we employ
for opening and closing the inlet and outlet ports or air passages.
In like manner we employ two or more packing rings on the piston to insure
the main inlet or air passage connected to the air chamber being thoroughly
air tight.
At each end of the said cylinder we connect by a screw joint a cover, having a
leather, indiarubber, or other flexible lining backed by a metallic spring forming &
joint and a cushion for the purpose hereinafter described.
The upper end of the cylinder is provided with a screw box or socket for
connecting thereto a flexible pipe, for supplying the compressed air to the cylinder.
We connect the cylinder horizontally that it is at right angles to the apex of the
shear frame or the cylinder and the shear frame may form one part.
We attach to a convenient part of the piston but preferably to a part near the
exhaust a projecting pin to which is attached an anti-friction roller which fits the
fork end of the lever attached to the shears mechanism.
On the fork part of the said lever we connect a compensating anti-friction roller
for counteracting the tension to the shear mechanism.
In cases of high pressure we employ an additional double acting valve attached
to the plunger valve for regulating the pressure applied thereto.
The shears are operated by the motive power of the compressed air cylinder in
the following manner
- 1 -

page_text: Compressed air being admitted to the cylinder by means of a flexible pipe the
air entering at the top of the cylinder enters the air chamber before described,
passes through the backward port or air passage in the bottom thereof and thence
into the annular opening formed in the end of the plunger valve admitting the air
to the back of the piston which is driven forward to its terminus at the opposite
end of the cylinder (the plunger-valve abutting against the flexible lining or cushion
before described) the effect of which is to complete one part of the stroke of the
shears.
The backward ports or air passages being closed by the packing rings covering
them, and the forward ports being opened by the lateral movement of the packing
rings on the fore end of the plunger valve being removed by the same action which
admits the air to the fore end and drives the piston backward thus completing the
stroke of the shears.
It will thus be apparent that by the relative positions of the ports or air passages
during the to and fro movement of the piston and the plunger valve it will
give a simultaneous movement to the piston and hence to the mechanism of
the shears.
Dash: gond dox of Datobar 1901
RAYNER & CASSELL,
37, Chancery Lane, London, W.C., Agents for the Applicants.
COMPLETE SPECIFICATION.
An Improved Compressed Air Engine for Working Shears, and other
like purposes.
We, JOSEPH FLETCHER of 111 Dolobran Road, Sparkbrook, Birmingham,
Engineer, and FREDERICK HUGGINS, and HENRY HUGGINS both of the
Britannia Tube Works, Glover Street, Birmingham, Tube Manufacturers, 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 :-
Our invention has for its object the adaptation of a compressed air engine of
improved construction to the working of shears, which has hitherto been effected
by hand.
Our improved power shears may be used for shearing cattle, sheep, horses, and
other animals, and is also applicable for cutting the human hair. The motive
power we prefer to use is compressed air, which may be obtained in various manners,
but is preferably compressed in steel bottles, for convenience of transport, these
bottles being provided with a reducing valve so as to allow of the air being supplied
to the engine at the required pressure; we may also use in the same engine hot air
or steam as a motive power.
In carrying our invention into practice, we provide a T shaped shell or casing,
consisting of a cylinder arranged horizontally on the top of a vertical tubular
frame, terminated by a horizontal extension, within which the movable cutting
blade of the sbears works upon a fixed blade, attached at the back of the said
extension and provided as usual with long narrow teeth at its lower extremity,
this movable blade being attached to the lower end of a lever, fulcrumed on a
suitable pivot within the tubular frame aforesaid, the upper end of which is
forked and extends within the piston through an opening formed in the latter
and in the cylinder. This forked end engages with a roller mounted on an axis
fixed to the said piston.
In the cylinder or upper part of our improved power shears the two solid ends or
covers are screwed upon the edges of the body, a resilient packing, forming a joint
and cushion combined, being interposed therebetween. Within the cylinder moves
a piston of peculiar shape and hollow centrally to receive a plunger valve, furnished
with suitable inlet and exhaust ports and corresponding packing rings, for closing

page_text: Fig. 1 is an elevation of our improved power shears,
Fig. 2 is an end view and
Fig. 3 a vertical section of the same.
Fig. 4 is a central cross section of the piston and
Figs. 5, 6 and 7 are detailed views of the same.
Our improved power shears consist of a horizontal cylinder C, forming an integral
part of a tubular frame A, and mounted on the top of the latter, the lower extremity
of which is enlarged as shown, and forms a casing wherein moves the movable
blade B', as it works upon the fixed blade B, secured at the back of the enlarged
part of the frame A, and furnished at its lower end with 'long pointed teeth, as.
clearly shown in Figs. 1 and 3.
The blade B' forms the lower end of the lever L fulcrumed at upon an axis.
secured to the tubular frame A; the upper end of this lever is forked to engage
with the roller h, mounted on a pin secured to the piston P.
The lever L is further provided with a projection forming an axis for the
roller a, which moves upon a curved path y extending across the tubular frame A
(Fig. 3). The cylinder C forming the upper part of our improved power shears is.
screw threaded at each end to receive the covers o o³, inside of which is arranged a
packing of leather, india rubber or other flexible material, supported at the rear by
a metallic spring, so as to form a cushion at each end of the cylinder for the
purpose hereinafter set forth. The cylinder C has a screw threaded neck or inlet c,
whereby it may be connected to any suitable supply of compressed air. Within
the cylinder C moves the piston P, tightened by the packing rings and having a
central cylindrical opening u (Fig. 4) wherein the plunger valve V is located and
is allowed a travel limited by the pin 4 extending across the piston through the
slot, formed in the centre of the said valve. The piston is divided into two
chambers, an air chamber at the top communicating with the inlet and an
exhaust chamber W at the bottom, communicating with the tubular frame A and
hence with the atmosphere. The plunger valve is provided with admission
ports i and, and with exhaust ports e e¹, the latter being placed in communication
with the exhaust chamber w through the ports p p formed in the inner tubular
part of the piston P, these last ports being successively closed by the packing
rings of the valve V, which is provided with two more packing rings
closing successively the admission ports above mentioned, are ordinary packing
rings used for tightening purposes. The piston occupying the position shown in
Fig. 3 and the neck or inlet c being connected to the supply of compressed air, air
will enter the chamber, pass through the port and enter the annular opening
formed at t, between the reduced end of the plunger valve V and the inner
cylindrical surface of the piston P, thus passing under the same and impelling it
on its forward stroke until it reaches the end of the cylinder. But before this
occurs the end o' of the valve V abuts against the cushion in front of the cover o
and admits air, forming an air cushion to the air chamber and is pushed back
thereby a distance determined by the travel of the slot against the pin, thus
disclosing the admission port i and closing the port by means of the ring 3,
while at the same time opening a communication between the exhaust ports e¹ and p¹,
allowing the exhaust air to escape into the atmosphere. A reversal of the above
mentioned cycle of operations will take place during the backward stroke, the
port i being closed by the ring and the exhaust e placed in communication with
the port p while the port is opened and the exhaust port pl is closed by the
ring r
む

page_text: Having now particularly described & 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 power shears consisting of a compressed air engine actuating the lever L
carrying the movable blade B' and fulcrumed within a tubular vertical frame A
carrying the fixed blade B and formed integrally with the horizontal cylinder of
the said engine, substantially as herein described and shown.
(2) In power shears such as above claimed the combination of the vertical
tubular frame A, air chamber Z and exhaust chamber W, with a cylinder C, a
piston P provided with admission ports and exhaust ports p p² and containing
a plunger valve located in a central opening u of the same and furnished with the
packing rings for closing the admission ports, with the packing rings rr
for closing the exhaust ports p på and with the exhaust openings or passages e
substantially as herein shown and described.
e'
(3) The improved power shears arranged, constructed and operating substan-
tially as herein described and shown and for the purpose set forth.
Dated this 4th day of March 1892
RAYNER & CASSELL,
37, Chancery Lane, London, W.C., Agents for the Applicants.