Improvements in Apparatus for Compressing Gas, Air, or the like.
Year: 1899

page_text: Date of Application, 21st June, 1899
Complete Specification Left, 19th Mar., 1900-Accepted, 21st June, 1900
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Compressing Gas, Air, or the like.
We, CHARLES SCOTT SNELL and FREDERICK ALLIBON SNELL, both of Culver
Park, Saltash, in the County of Cornwall, Engineers, do hereby declare the
nature of this invention to be as follows:-
This invention relates more especially to improvements in appliances adapted
for increasing the pressure of gas for incandescent gas lighting, though obviously,
air or gases, other than coal gas, may be compressed by the same means.
In carrying out our invention we make use of a casting or frame having certain
recesses or pockets arranged in pairs, back to back, thus constituting two faces.
Each face provides a larger recess for the attachment of a diaphragm or piston,
the pulsation of which alternately draws in and compresses the gas, and a smaller
recess fitted with a diaphragm or piston which is actuated by the " power"
utilized, such as water. The pulsation or motion derived from the latter is con-
veyed to the diaphragm through rocking levers preferably oscillating on knife
edges or centres; extensions thereof actuate the controlling valves. These valves,
which may be of any convenient type, are operated by connecting levers so that
the power is always on one water vessel, and before the power supply is cut off the
one it is turned on in the adjacent one. Continuity is thereby ensured, and the
return stroke or inspiration of the gas compressor being affected by springs,
quick action is ensured, one section remaining therefore ready for compressive
action, directly the adjacent section has reached within a prearranged distance
of the end of its stroke. It then affects the supply valve and throws its neigh-
bour into action.
The oscillating levers we arrange with moveable fulcrums to give variability
as regards leverage. To adapt the machine to higher pressure than that for
which it is normally constructed, we put in a smaller piston with an annular
packing ring around it, where a diaphragm is used, or when a cylinder is used,
we supply copper liners with a flange, having different diameters in the tubular
part, whilst the flanges are constant in diameter.
Where projection from a wall is objectional we may use separate sections
mounted on a base side by side, in place of back to back as described. The gas
vessels have inlet and outlet valves, and these may be attached to a dished or
flat disc forming a removeable diaphragm, in the one case, and the pulsating disc
in the other. Gas being led inside the covers, it is compressed into the space
between the rigid diaphragms by the movements of the pulsating diaphragm or
its equivalent.
By this system ready adaptation is effected to extreme ranges of water pres-
sure, nicety of final adjustment is possible, and the need of a gas holder to con-
trol the machine by operating the water feed valve is obviated. The lever
arrangements have a minimum of friction and cause the local water pressure to
balance the pressure of the compressed gas and therefore the consumption of
water is in close proportion to the gas compressed, thus ensuring high efficiency.

page_text: Water in the prime mover may be replaced by compressed air or steam, if
these sources of power are more convenient to use.
1
011
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1000
C. SCOTT SNELL.
F. ALLIBON SNELL.
Improvements in Apparatus for Compressing Gas, fir, or the like.
We, CHARLES SCOTT SNELL and FREDERICK ALLIBON SNELL, both of Culver
Park, Saltash, in the County of Cornwall, 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 more especially to improvements in appliances adapted
for increasing the pressure of gas for incandescent gas lighting, though obviously
air or gases, other than coal gas may be compressed by the same means.
The accompanying drawings in which similar figures refer to similar parts
show apparatus constructed in accordance with our invention.
Figure 1 is a section and Figure 2 a side elevation of one arrangement.
Figure 3 is an enlarged section of a water valve.
Figures 4 and 5 are side elevation and plan respectively of a modified adjust-
able leverage arrangement.
Figures 6 and 7 show an apparatus adapted for circumscribed space.
Figures 8 and 9 show methods of reducing the area of the water division.
Referring to Figure 1, it will be seen that a casting or frame A is used, having
two faces, each being recessed to accommodate a gas diaphragm and a water
diaphragm, so that the pulsation or motion derived from the latter marked B
and is conveyed to the former marked C and C¹ through rocking levers
marked D and D and E and E oscillating on knife edges or centres, recoil
springs J and J¹ are fitted to the levers E, E¹.
The constructive details are clear from the drawing the outside covers when
bolted down holding the pulsating diaphragms, and in the case of the gas
division the rigid diaphragm C² and C³.
Extensions K and K of the levers E and E actuate the controlling valve (see
Figure for-enlarged section) at the head of the machine, striking, at the end
of each stroke, the arms F and F alternately; these are connected by other arms
and rocking bars to each other and to a tap G the actuation of which allows the
fluid to operate the valve (Figure 3), the system working as follows:-
Whilst the gas diaphragm C is being driven in by the water pressure on the
diaphragm B the water is entering through the corresponding port (see enlarged
section Figure 3) its exhaust outlet being closed, water is meantime being
expelled from the other water division by the power of spring J¹, the exhaust
aperture being open and the water inlet closed in that case.
This latter division remains inoperative until the full stroke of the first
division nearing completion, causes the tap G to be reversed, the pressure being
thereby admitted to the head of piston L and the valve therefore reverses itself
on account of the extra area of the disc N over that of the disc N. The valve
is so proportioned that in reversing it opens the water supply to one division
before closing the other, thus ensuring continuity of water feed.
The feed passages are marked H and H and the exhaust passage I. A pipe M
connects the tap G with the water supply and a pipe M¹ connects it with the
exhaust passage.

page_text: The oscillating levers provide variability as regards leverage, the fulcrum of
the lever D, and that of lever D₁ being carried on screwed spindles O and 01
(Figures 1 and 2) or they may be carried by bearers 02 having slots 03 engaging
bolts 0 (Figures 6 and 7) to admit of adjustment according to water pressure.
The power exerted is transferred through blocks D2 and D³ to the levers E and E'
and to the gas diaphragms actuated thereby..
A very large range of leverage is thus possible but for machines working
within smaller limits the levers D and D may work direct upon the gas
diaphragm rods C and C³, or the blocks D2 and D³ may be movable on the
levers E and E¹ and the screwed spindles O and 0 replaced by rigid bearings.
Figures 4 and 5 side elevation and plan respectively show an alternative way
of carrying the fulcrum, of lever D and of lever D¹ by a spindle passing through
the two blocks, which may then be adjusted in any desired position in the
elongated slot.
Where circumscribed space necessitates departure from the above described back
to back arrangement separate sections may be mounted side by side as shown in
Figures 6 and 7 thus projecting less from the face of a wall. In this case the
main casting may also be somewhat modified from that in Figures 1 and 2 as.
shown thus further reducing the space occupied. The valve also becomes
simplified; each division then being complete in itself, forming as it were a
single acting machine. The action of this type of the machine is similar to that
above described but the gas valves V and also Y and Y are preferably kept
outside. In each case the gas is first led into the space above the pulsating gas
piston in order to make the suction on the gas main approximately steady, the
quick recoil movement merely sending the gas through the intervening valve
(marked V and V₁ in Figures 1 and 7) and the return or compressing stroke
delivering it through the valves Y and Y₁ into the space Z between the rigid
diaphragms in the case of Figure 1 and the equivalent space Z in Figure 7, that
is into direct connection with the high pressure service to the lamps.
Where a machine is designed for low water pressure and has to be adapted to
a very much higher pressure which would make the load on its piston excessive,
we put in a smaller piston with an annular packing ring P around it where a
diaphragm is used as shown in Figure 8. Where a cylinder is used we supply
a liner with a flange Q suitable for the machine but the tubular portion R, see
Figure 9, would in each case be of a different diameter to suit the particular
water pressure, the piston being reduced accordingly.
Thus the initial piston lead being kept approximately constant, final and exact
adjustment may be effected at the levers.
By this system ready adaptation is effected to extreme ranges of water pres-
sure, nicety of final adjustment is possible, and the need of a gas holder to con
trol the machine by operating the water feed valve is obviated.
The lever arrangements have a minimum of friction and cause the local water
pressure to balance the pressure of the compressed gas and therefore the con-
sumption of water is in close proportion to the gas compressed, thus ensuring
high efficiency.
Water in the prime mover may be replaced by compressed air or steam, if
these sources of power are more convenient to use.
Having now particularly described and ascertained the nature of our said
nvention and in what manner the same is to be performed we declare that what
we claim is:-
1. In a machine for compressing gas or air, suitable for use in connection with
ncandescent gas lighting, gas and water chambers fitted with flexible
liaphragms, or their equivalent, with motion transferring levers so arranged.
s to admit of readily adjusting the leverage, that the water load may be balanced
y the gas load, substantially as herein described with reference to Figures 1, 2, 6
nd 7 of the annexed drawings.

page_text: 2. Apparatus for compressing gas or air, in which the pressure of water acts
on an oscillating diaphragm B and transmits the motion to a second oscillating
diaphragm C by means of an adjustable lever 1, the gas being compressed by
the diaphragm C and forced through an outlet valve Y into the space Z and from
thence to the burner pipes, whilst the entrance of the gas from behind the
diaphragm C after the pressure water has been automatically cut off is effected
by means of a return valve V through the spring J returning the diaphragm C,
as set forth; the diaphragms and their appurtenances being arranged in single
order, as at Figures 6 and 7, or double order, as at Figures 1 and 2.
3. In a machine as above described, the method of adapting it, when primarily
designed for a low water pressure, to a high water pressure by reducing the area
of the water diaphragm or piston, as described and illustrated in reference to
Figures 8 and 9.
R. CORE GARDNER,
Patent. Agent, 166, Fleet Street, London,
Agent for the said Charles Scott Snell and Frederick Allibon Snell.