Improvements in Air Compressing Machines.
Year: 1898

page_text: Date of Application, 8th Mar., 1898-Accepted, 30th Apr., 1898
Communicated from abroad by PHILIPP CRAMER, of Newark, in the County of
Essex, State of New Jersey, United States of America, Mechanic.
Improvements in Air Compressing Machines.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent Agents,
45, Southampton Buildings, in the County of Middlesex, 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:-
My invention relates to that class of air compressing machines, wherein a series
of compressing cylinders have pistons which complete their strokes consecutively,
and afford a continuous and uniform delivery of compressed air to an air receiving
chamber or reservoir. The objects sought by me are simplicity and economy in
construction, facility in adjustment and repair, steadiness and smoothness in
operation, economy in power at effective speed and a high degree of efficiency.
A characteristic feature of machines embodying the main portions of my inven-
tion, is a series of pump cylinders, each of which is within a segmental cast metal
section provided with an interior space, so that when the several sections are
properly united, the several spaces communicate with each other and afford an
annular chamber common to all of the cylinders, for the reception of air under,
pressure. As an additional novel feature, each of said sections has a second
interior space, so that all of the spaces afford an annular cooling chamber for the
circulation of water around all of the cylinders, and adjacent to the air chamber,
for preventing the undue heating incident to the working of air under high pres-
sure. These segmental sections when properly united, form an annular structure
presenting the several cylinders in radial lines, and the whole serves as the main
portion of the frame of the machine, which may be arranged to occupy either a
horizontal or a vertical plane, suitable legs or base blocks being readily attached
to any desired number of the sections. With the exception of such of the seg-
mental sections as are provided with pipe connections, the remainder are counter-
parts, so that when repairs are needed, a section may be readily removed and
another substituted from one or more extra sections provided for such emergencies.
Another feature of my invention consists in a novel combination of a series
of stationary; radially disposed cylinders, annularly arranged in pairs, diametric-
ally opposite each other; the pistons of each pair being coupled together and
simultaneously operated by a single cam, mounted in line with the piston upon a
central driven shaft and common to all of the pistons.
In this combination, the cam operates with a practically direct thrust upon each
piston, thus obviating the use of the pitmen or other vibrative mechanical con-
nections, common to prior machines wherein cranks, or eccentrics, or cams have
been employed within rings or frames to which the vibrative connections have
been coupled. The absence of such vibrative connections, obviates liability of
"back lash" at the pumps, and the use of stationary cylinders, obviates the many
complications incident to an axial delivery of compressed air, common in prior

page_text: machines wherein the several cylinders are carried in rotative structures or
frames.
My invention further embodies other novel features, hereinafter duly set forth.
Referring to the accompanying drawings:
Figure 1, illustrates one of my air compressing machines in side elevation, a
portion of the framing and outer sections or castings being broken away for dis-
closing interior portions of the apparatus.
Figure 2 is a lateral cross section of the same on line a, a, of Figure 1.
Figure 3, is an enlarged sectional view through one of the cylinders, its piston
and operating mechanism.
Figure 4, illustrates in side view a pair of pistons, their anti friction rolls, and
two of the four metallic straps which couple the pistons, said straps being broken
away centrally.
Figure 5, is a longitudinal section through one of the segmental sections which
contain the cylinders and constitute the main framing of the machine.
Figures 6 and 7, illustrate the same in end and top views respectively, and
Figures 8 and 9, illustrate a modification of means for securing a slight yielding
or cushioning effect between the cam and anti friction wheels on the pistons.
The outer portion of my compressing machine, containing the cylinders A,
annular receiving reservoir B, and water space C, is made up of numerous counter-
part segmental sections a, firmly united together by means of bolts and suitable
air tight packing, so that they constitute the main portion of the frame of the
machine. The central shaft 1), carrying the operating cam E, is mounted in
adjustable bearings formed in side plates F, having radial arms bolted to the
sections a, and at suitable points near the bottom of the main framing, I provide
two of the sections a, with legs by which the apparatus may be bolted to a suit-
able base, all as clearly illustrated in Figure 1.
Each of the cylinders A, at their outer or discharge ends, communicate with
the annular air receiving reservoir B, which is afforded by the spaces in the
numerous sections a, and which has an outlet as at b, (shown in Figure 1) for
delivering compressed air for any desired service. The enclosed ends of the
cylinders communicating with the receiving reservoir, are normally closed by a
valve a¹, which has secured to its outer side a guiding ring a², for co-operating
with guiding lugs a³ Figures 3, 5 and 7, cast integral with the section a, and
within an opening a Figure 7, in the periphery of the said section and in line
with the cylinder. This opening a, has an air tight cover a Figures 1, 5 and 6,
and is made necessary for finishing the interior surfaces of the several parts, and
for the insertion and adjustment of the valve a¹.
For properly controlling the valve a¹, it is provided with a spring a, inter-
posed between the valve and cover, a³, before referred to. This spring a, encircles
a spindle a', which is secured to the back of the valve a¹, and which slides in a
recess formed in the cover a³, for guiding and limiting the movement of the valve.
The valve a¹, only opens when the compression of air in the cylinder is sufficient
to overcome the spring and the pressure of air in the receiving reservoir.
Air enters each cylinder A, through an air space g, between its piston G, and
cylinder A. This air space is formed by the piston being cut away for almost its
entire peripheral distance, leaving only sufficient bearing contact to insure a steady
movement, as shown in Figures 2, 3 and 4. Loosely mounted on the face of the
piston, is a packing ring g', which may be of the expansible variety, or solid and
snugly fitted to the cylinder A. This packing ring is loosely. connected to the
face of the piston by means of bolts g, which slide in holes formed in the heads
of the pistons, the heads of the bolts preventing the rings from becoming detached.
It will be seen that when the piston is being drawn from the cylinder, the
packing ring gl, will be held back by its frictional engagement with the cylinder,
until controlled and moved by the bolts g. With the ring thus carried, the air
space g, is opened and air freely enters the cylinder. While the piston is being
forced into the cylinder, the reverse action of the ring g¹, closes the air space 9,

page_text: and compression takes place. It will be noticed that the under side of the
valve a¹, has a projection which affords an annular recess which at the completion
of the stroke of the piston, is occupied by the ring, and said projection com-
pletely fills the interior space of the ring g¹, thus insuring a desirable clearance,
or practically complete discharge of all the air from the cylinder.
The pistons G, are each provided with two parallel rearwardly extending
arms 3 and 4, each strengthened by two webs g³, g, and having at their inner
ends, bearing blocks g6, for a shaft, carrying an anti-friction wheel or roller H,
and also for affording abutments for adjusting screws to be hereinafter referred
to. The wheels or rollers H, are mounted between the arms g³ and g, and are
engaged by the periphery of the cam E, from which the pistons are operated.
The pistons G, of each oppositely located pair of cylinders, are rigidly coupled
together by means of four flat thin metal straps i, i, i, i, two on each side of the
pistons, and between which, the cam E, and rollers H, are located. The ends of:
the connecting straps i, on each side of the piston, are secured to yokes ¹, which
slide in slots 2, formed in the webs g5, of the piston arms g³ and g, and each
yoke is provided with an adjusting screw ³, for tightening the straps i, and for
adjusting and keeping the rollers H, in proper relation to the cam E.
It will now be seen that by coupling the pistons in the manner described, the
bearing blocks 96, are well controlled and that while a piston is being forced
outwardly by the action of the cam E, the opposite piston will be simultaneously.
drawn inwardly by the coupling straps 2.
For affording a true and steady movement of the pistons, the end of the roller
shafts h, are provided with guiding blocks f, which slide in guide f¹ secured to
the radial arms F' of the side plates F, as clearly shown in Figures 1, 2 and 3.
The chamber or water space C, for cooling the cylinders and air receiving reser-
voir, is afforded by interior spaces in the sections a, as before described, the water
entering through a pipe c, provided with a suitable stop-cock, and connected to
one of the sections a, near the bottom of the apparatus, and discharged at an
outlet pipe c¹, similarly connected to one of the sections a, near the top of the
apparatus, and which is also provided with a suitable stop-cock, all as clearly
shown in Figure 1. It will be seen that this water space C, is quite large as
compared with the air receiving reservoir, and water therein will be in contact
with the inner wall of the air receiving reservoir, and also surround a portion of
the exterior surface of each of the cylinders; the one water space serving to reduce
the temperature of both the receiving reservoir B, and the cylinders A.
Power is applied to the shaft D, by means of a belt and pulley, or gearing (not
shown), and the cam E, being keyed thereto, all of the pump pistons are kept in
motion and the several pairs of pistons are fully operated successively. Owing
to the difficulty in constructing the cam E, so that it will at all times completely
fill the space between the rollers H, of each pair of pistons, I provide the rollers H,
with yielding tyres h², usually composed of rubber. These tyres h2, because of
their yielding capacity, are in contact with the cam E, and cushion between the
cam and rollers, except during the heavy thrusting action, and hence, such slight
noise and shock as might otherwise occur, is obviated.
In Figures 8 and 9, I show a modification of means for securing a similar yielding
effect, by the use of springs h³, interposed between the bearing blocks g6, and the
journal boxes of the wheel shafts h, and provided with adjusting screws h. For
assuring a free rotation of the wheels by the cam, during the forcing action of
the cam, and especially in heavy machines, I provide the peripheries of the wheels
and cam, with teeth k, and ¹, which do not prevent annular surfaces of the
wheels, and the working surface of the cam from being closely engaged during
the heavy thrusting action of the cam, and when employed with the cushioned
wheels, said teeth cannot over ride each other, one set of teeth being recessed, and
both sets being of ample length to always co-operate.

page_text: Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is:-
1. In an air compressing machine, the combination substantially as herein-
before described, of a series of segmental sections, each containing a pump cylinder,
and also an interior space communicating with the cylinders and means for uniting
said sections and thereby forming the whole into an annular structure, serving
as the main portion of the frame of the machine, and the several interior spaces
affording an annular chamber or reservoir for receiving compressed air from all
the cylinders.
2. In an air compressing machine, the combination substantially as herein-
before described, of a series of segmental sections, each containing a pump cylinder
and also separate interior spaces, and means for uniting said sections for forming
an annular structure serving as the main portion of the frame of the machine,
and the said separate interior spaces affording separate annular chambers, one
for compressed air and the other for the circulation of cold water for keeping
down the temperature of the machine.
3. In an air compressing machine, the combination of a series of segmental
sections bolted together and forming an annular frame, a series of radially
arranged air pumps enclosed in said frame and a pair of central frame plates
provided with radial arms, each firmly coupled to a section, and each provided with
a radial guide slot in line with the adjacent pump for assuring a proper move-
ment of its piston, substantially as described.
4. In an air compressing machine, the combination substantially as herein-
before described, of a series of stationary annularly arranged pump cylinders,
grouped in pairs diametrically opposite each other, and having the pistons of each
pair rigidly coupled together, and an operating cam mounted upon a central shaft
between each pair of pistons and common to all of them.
5. In an air compressing machine, the combination with an annular air receiving
reservoir, of a series of diametrically oppositely arranged pumps, each having its
piston coupled to the piston of the opposite pump, and an operating cam mounted
on a central shaft common to all pistons, substantially as described.
6. In an air compressing machine, the combination of a series of stationary
annularly connected pumps arranged in pairs diametrically opposite each other,
and having the pistons of each pair coupled together, an operating cam common
to all of the pistons and means for adjusting the pistons with reference to the
cam, as and for the purpose specified.
7. In an air compressing machine, the combination of an annular receiving
reservoir, a series of air pumps, and an annular chamber affording water space
closely adjacent to the reservoir, and also surrounding a portion of each pump,
substantially as described.
8. In an air compressing machine, the combination of a series of annularly
arranged pumps, a cam for operating all of the pumps, pump pistons which are
cushioned with relation to the cam, and means for coupling each pair of diametric-
ally opposite pistons, substantially as and for the purposes specified.
9. In an air compressing machine, the combination of a pump cylinder, a
piston having an air space or induction passage at its periphery, and a packing
ring, loosely mounted upon the face of the piston and operating as a valve cover to
said induction passage, substantially as described.
Dated this 8th dor of Manh 1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.