Improvements in Pneumatic Transmission Systems.
Year: 1899

page_text: Date of Application, 20th July, 1899-Accepted, 28th Oct., 1899
COMPLETE SPECIFICATION.
Improvements in Pneumatic Transmission Systems.
I, BIRNEY CLARK BATCHELLER, of No. 1,518, North Fifteenth Street, Phila-
delphia, Pennsylvania, in the United States of America, Mechanic, do hereby
declare the nature of this invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, and accompanying drawings, that is to say: -
My invention relates to a system of transmitting carriers in pneumatic despatch
tubes and has for its object to provide an improved system which can be worked
to a high degree of efficiency at comparatively moderate cost and with great
simplicity of apparatus.
The essential feature of my invention consists in connecting two stations by a
transmission tube, having its receiving end connected to a source of air under
pressure and its delivery end open to the atmosphere, and in connecting the
delivery end of such tube, a short distance in the rear of its open end, with the
suction pipe of a blast fan or air compressor. The delivery of air to the trans-
mission tube from the source of air under pressure, which is, conveniently, a
fan or compressor of the same character as that connected with the delivery end,
should be substantially the same in amount as the air drawn from the pipe at the
said delivery end, and it will be readily understood that, working in this way,
the air pressure is at its maximum at the receiving end of the tube, falling
gradually to atmospheric pressure at the point where the delivery end of the
pipe connects with the air pump, so that there is, or need be, little or no movement
of air through the delivery end proper, that is, the portion of it in advance of the
pump connection. In practice two transmission pipes working in opposite direc-
tions connect each pair of stations and an air pump at each station is most
conveniently connected to force air into the receiving end of the pipe leading
from the station and to draw air from the delivery end of the transmission pipe
leading to the station.
In applying my invention to the construction of a system involving a multiple
series of stations, adjacent stations are coupled in pairs, all the carriers passing
through the system being delivered at each station, and those destined for a
further station delivered again to the receiving device of the tubes connecting
the next pair of stations. In this multiple series I may connect the air pumps
or similar devices so that the air is forced from the transmission tube leading
to a station to the transmission tube leading to the next station in consecutive
order and so on, so that it traverses the entire multiple series of stations; prefer-
ably, however, the air pumps are connected so as to receive and force the air
going to a station from another station coupled with it, back into the transmission
pipe leading to the station from which the air came, so that the system for each
pair of stations is entirely separate and independent from the transmission systems
coupling the other stations. An advantage of this construction being that, in case

page_text: of the stoppage or breakdown in the system coupling any two stations, the
operation of the other couples will not be interfered with and they may all remain
in full operation.
Another feature of my invention, which involves the use of a considerable
number of independent pumps or blowers situated in different stations of the line,
consists in operating such pumps or blowers by a series of independent electric
motors and supplying current to all such motors through circuits connected with
a common electric generator.
Other features and modifications of my invention will be best understood as
described in connection with the drawings in which my invention is illustrated,
and in which,
Figure 1 is a diagrammatic view illustrating my invention as applied to a
multiple series of stations.
Figure 2 is a similar diagrammatic view illustrating another and my preferred
modification of the application of my system to a multiple series of stations.
Figure 3 illustrates another modification of my invention applied to a multiple
series of stations.
Figure 4 is a plan view showing the delivery end of one tube, the receiving end
of the other tube, the transmitter used in connection with the receiving end of
the tube, and the receiving table used in connection with the delivery end of
the tube and having, as shown, a chute connection with the transmitting device.
Figure 5 is a side elevation of the transmitter and the end of the receiving
table as shown in Fig. 4.
Figure 6 is a sectional elevation taken on the line 6-6 of Fig. 4.
Figure 7 is a cross sectional elevation taken on the line 7-7 of Fig. 4.
Figure 8 is a cross-sectional elevation taken on the line 8-8 of Fig. 5.
Figure 9 is a longitudinal sectional elevation taken on the line 9-9 of Fig. 8,
and
Figure 10 is a sectional elevation of a closed receiving device used in connec-
tion with one modification of my invention.
A A¹ A and A³, Figs. 1, 2 and 3, indicate separate stations of the system on
the line. B, B1 and B2 are outgoing transmission tubes, coupling the stations in
pairs, from the end station A to the end station A³. C C and are incoming
transmission tubes, coupling the stations in pairs, and leading from the station A³
to the station A. D, D¹, d', D³, d³, and D³ indicate air compressors or blowers
situated in the separate stations and each, as shown, driven by an electric motor,
such motors being indicated at F, F1, f, 12, and F. E indicates an electric
generator common to the system, from which lead circuit wires E and E2 con-
necting, as shown, directly with the motors F and F³ in the terminal stations and
through branch wires indicated at ee and with the motors in the inter-
mediate stations A and A2. G, see particularly Figs. 4 and 6, indicates the open
delivery end of the transmission tube, the tube being preferably cut away for
half or slightly more than half of its diameter at this point, and the substantially
semi-circular section continued in a curve, as indicated at G¹, said curved section
terminating preferably with a buffer, as indicated at G2. It will be understood,
however that the full section of the tube may be continued for any desired distance
on the curve; thus in Fig. 4, I have indicated in dotted lines the continuance of
the full section of the tube to the point marked g. G3 indicates a receiving table
extending inward from the bottom of the curved section of the pipe G¹, as best
shown in Figs. 4 and 7, the table being slightly inclined and provided with a rail
as indicated at G₁ for preventing the carriers from rolling off. G indicates a
chute extending from the end of the inclined receiving table to the transmitting
device to be hereafter described. It will be understood that the carriers issuing
from the pipe B will have their momentum greatly checked in passing around
the curved section G¹, and that if the momentum is sufficient to carry them
cntirely around this section they will be stopped by the buffer G, and that in all
cases the carriers as soon as their propulsive momentum is lost will roll forward

page_text: or inward on the table G³ until they rest against the rail G+, from which position
they can be removed or thrust into the chute G5.
H indicates an annular head surrounding the transmission pipe B at a point
near its open delivery end G, the pipe B within the head being slotted, as indi-
cated at to permit the free passage of air. As shown, the head H connects
directly with a union casting H and through it with the pipe K, the casting H¹
having also, as shown, lateral extensions indicated at H2, having an open end h²
and also at H³ having an open end h³. I indicates a regulating gate or valve
adjusted by a screw I and fitting on the open end of the passage H. By adjust-
ing this gate provision may be made for the introduction of any desired amount
of air through the passage H2. J is a sliding plate having a portion J¹ which,
in the position shown in Fig. 6, closes the passage from the head H through the
casting H¹; the plate has also an opening J which, in the position shown, regis-
ters with the opening through the passage H³ permitting the passage of air
freely through said passage and the casting H¹ to the pipe K. In normal opera-
tion the plate J is drawn out so as to open freely the passage between the head H
and the casting H', in which position its solid portion J¹ closes the passage H³.
K is the suction pipe or conduit of an air pump or blower, such as is indicated
at D D etc. L is the delivery pipe of the compressor or blower which leads, as
shown to the receiving end of one of the transmission tubes,
M is what I may call a transmitter, that to say, a device for facilitating the
introduction of carriers into the receiving ends of the tubes. Any convenient
device for this purpose, of which many are well known, may be used. The one I
have illustrated is best shown in Figs. 8 and 9; a portion of the receiving end of
the tube, such as is indicated at B¹, is cut away; the adjacent ends are surrounded
by annular boxes, as indicated at M1 and M2, m¹ and m² indicating the adjacent
opposite ends of the severed tube. The tube within the boxes is slotted and the
sections connected by a curved passage, as indicated at M³. M4 M indicate
standards supported on the box M¹ and M2 and supporting at top a shaft M5
to which in turn is secured a swinging bracket M6 formed with face
plates, as indicated, which close the tube ends m² m² except where
the transverse tubes M7 and m² are secured to said face plates, said tube
sections being adapted to register with the tube ends as the bracket is swung from
one position to the other, which may be conveniently accomplished by the lever
arm Ms. The carrier is introduced to the transmission tube by inserting it, for
instance, in the tube section m7, and then swinging the bracket until said tube
section registers with the tube ends m¹ m² when the blast of air will sweep the
carrier out of the transmitter into the transmission tube.
It will be understood that in the operation of my system air is forced into the
receiving ends of the tubes by a blower or compressor and that a blower or com-
pressor of similar capacity and speed is used to draw the air from the delivery
end of the tubes so that the pressure in the tube is at its maximum at the receiv-
ing end, gradually and uniformly falling to atmospheric pressure at its delivery
end, and it will also be understood that there is or need be practically no move-
ment of air in the delivery tube beyond the point at which the suction end of the
compressor is connected so that the carrier after passing this connection is carried
forward merely by its momentum which is conveniently taken up on the curved
receiving section. Some air is almost inevitably lost from the tube by leakage
between its receiving and delivery ends and therefore there is a tendency toward
an actual inflow of air from the open end G of the tube to the box H. This may
be availed of if desired, as a means for checking the momentum of the carrier,
and it may be modified or entirely obviated by providing for an independent
inflow of air into the suction tube K through an opening other than the open end of
the tube; thus, the gated opening H2 may be used for this purpose or by adjusting
the slide plate J, the opening H³ will serve the same purpose, as well as the purpose
for which it is expressly provided, namely, as an opening through which the
compressor may draw its entire supply of air at such times as the transmission

page_text: tube used in connection with it is out of service, or at such times as it is desired
to cut off the connection between this transmission tube and the suction pipe so
as to raise the pressure in the transmission tube in order to force a carrier out
which has become lodged in the pipe, or for any other purpose.
Referring now to the diagrams, it will be noticed, that in the connections indi-
cated in Fig. 1, the air passes from the blower D into the transmission tube B, thence
through the blower 1 into the transmission tube B¹ and so on, the air passing
from station to station and returning to the blower D in station A only after it has
made the entire circuit of the system. In Fig. 2, however, I have indicated a
system of connection which I prefer, the air passing from the blower D to the
transmission pipe B, thence to and from the blower d¹ to the return pipe C and
from its delivery end back to the blower D. Each of the other stations coupled in
pairs forms, like the one described; a complete and independent circuit so that
in case of obstruction impairing the service between any two stations the stations
on each side of it are still maintained in full operation, although the system as a
whole may be temporarily broken.
In the diagram, Fig. 3, I have illustrated a modification of my invention in
which the intermediate station A¹ is provided with no blowing or compressing
apparatus, but reliance had for the connections between A and A¹ and between A
and A entirely upon the compressors D and D. This is accomplished by the
use of a device such as is indicated in Fig. 10, the transmission tube B, for in-
stance, terminating in a closed receiver, indicated at N; this receiver being
pivoted at N¹. As shown, it is actuated through a connecting rod N³ by a piston
moving in the cylinder N, N5 indicating an escape pipe for air forced into the
receiver in front of a carrier. A short distance in front of the receiver the pipe B
is connected by a box H and a pipe b with the receiving end of return tube C.
g indicates a receiving chute into which the carrier is dumped from the receiver N,
9 indicating a stop or buffer at the end of the chute. In the use of this style of
closed receiver, the actuating cylinder № or other actuating device is arranged,
by means which are well known, to be set in operation by the entry of a carrier
so as to dump the carrier into the chute g¹ and return the receiver to position to
receive another. In this construction the tubes B and C are, from the point of
view of my invention, to be considered as practically one tube, the pressure being
at the maximum at the receiving end of tube B falling gradually to atmospheric
pressure at the delivery end of tube C. This modification may be useful under
certain conditions although it is obviously not capable of use to the same extent
as the preferred form of my invention in which no delivery of the carrier is
effected except at the open delivery end.
Of course it will be understood that all the different plans of connection between
stations which I have indicated and described may be used in a single system,
thus, for instance, in Fig. 3 I have shown the station A2 A3 connected as in
diagram Fig. 2.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
-
1. A pneumatic transmission tube having a delivery end open to the atmos-
phere and its other or sending end connected to a source of air under pressure in
combination with an air conduit connected to the transmission tube a short
distance behind its open delivery end and an air pump connected to draw air
through said conduit from the transmission tube.
2. A pneumatic transmission tube having its delivery end open to the atmos-
phere and terminating in a curve of comparatively short radius and its other or
carrier receiving end connected to a source of air under pressure in combination
with an air pump having its suction conduit connected to the tube a short distance
behind its open delivery end.
3. A pneumatic transmission tube having a delivery end open to the atmos-

page_text: phere and its other or sending end connected to a source of air under pressure in
combination with an air conduit connected to the transmission tube a short dis-
tance behind its open delivery end, an opening through said air conduit to the
atmosphere other than the delivery end of the transmission tube and means for
regulating the same, and an air pump connected to draw air through said conduit
from the transmission tube and the outer atmosphere in proportion to the adjust-
ment of the device regulating the opening in the air conduit aforesaid.
4. In combination with two stations of a pneumatic transmission system, two
transmission tubes connecting said stations respectively adapted to use in opposite
directions and each having its delivery end open to the atmosphere, and air
pumps at each station each having its delivery port connected to the charging
end of the tube leading from the station and its suction ports connected to the
delivery end of the tube leading to said station a short distance in the rear of the
opening into the atmosphere.
5. In combination with two stations of a pneumatic transmission system, two
transmission tubes connecting said stations respectively adapted to use in opposite
directions and each having its delivery end open to the atmosphere, air pumps
at each station each having its delivery port connected to the charging end of the
tube leading from the station and its suction ports connected to the delivery end
of the tube leading to said station a short distance in the rear of the opening
into the atmosphere and regulable air admission ports connected with the suction
port of each engine and whereby air can be admitted otherwise than from the tube.
6. A pneumatic transmission system comprising three or more stations con-
nected in pairs by outgoing and incoming transmission tubes, said tubes having
their receiving ends connected with a source of air under pressure and their other
or delivery ends open to the atmosphere, air conduits connected to the trans-
mission tubes a short distance behind their open delivery ends and air pumps
arranged to draw air through said conduits from the transmission tubes.
7. A pneumatic transmission system comprising three or more stations, each
connected to the adjacent station by an outgoing and an incoming transmission
tube, said tubes having their receiving ends in each station connected to a source
of air under pressure and their delivery ends in each station open to the atmos-
phere, an air conduit in each station leading from a point in the transmission
tubes near their open delivery ends, and air pumps in each station drawing air
from the transmission tubes through said air conduits.
8. A pneumatic transmission system comprising three or more stations, each
connected to the adjacent station by an outgoing and incoming transmission tube,
said tubes having their receiving ends in each station connected to the delivery
conduit of an air compressor situated at or near each station and their delivery
ends in each station open to the atmosphere, an air conduit in each station lead-
ing from a point in the transmission tubes near their open delivery ends to the
Buction conduits to the air compressors aforesaid, all substantially as described,
and so as to maintain one body of air in circulation between each two adjacent
stations.
9. A pneumatic transmission system comprising a series of stations, outgoing
and incoming transmission tubes connecting said stations in pairs, air compressors
situated in separate stations of the series connected to force air into the receiving
ends of the tubes and draw air from them at points adjacent to their delivery
ends, electric motors in the separate stations connected to drive the compressors,
an electric generator common to the system and circuit connections leading
therefrom to the motors aforesaid.
10. In a pneumatic transmission system comprising three or more stations con-
nected in pairs by outgoing and incoming transmission tubes, said tubes being
connected at their receiving ends to sources of air under pressure and open to the
atmosphere at their delivery ends, and air pumps having their suction conduits
connected to the delivery ends of the transmission tubes a short distance from
their open ends, the combination with a transmitter situated in the receiving

page_text: end of a transmission tube at one station of a curved delivery table, as G¹ G³,
connected with the delivery end of a transmission tube leading to the station and
a cliute as G5, leading from said table to the transmitter.
D
TI 1000
EDWARDS & Co:,
Chartered Patent Agents,
65 and 66, 'Chancery Lane, London, Agents for the Applicant.