US1148116A

US1148116A - Pneumatic-despatch-tube apparatus.

Info

Publication number: US1148116A
Application number: US56943910A
Authority: US
Inventors: John T Needham
Original assignee: Lamson Co
Current assignee: Lamson Co
Priority date: 1910-06-29
Filing date: 1910-06-29
Publication date: 1915-07-27
Anticipated expiration: 1932-07-27

Description

J. T. NEEDHAM.

PNEUMATIC DESPATCH TUBE APPARATUS.

APPLICATION FILED JUNE 29, I9I0.

Patented July 27, 1915.

2 SHEETSSHEET I.

AMA w 7/1 My TOR A Arromvfrs COLUMBIA PLANOGRAPH Cm. WASHINGTON, D. c.

J'. T.NEED HAM. PNEUMATIC DESPATCH TUBE APPARATUS.

APPLICATION. FILED JUNE 29,1910.

Patented July 27, 1915.

2 SHEETS-SHEET 2.

WITNESSES:

COLUMBIA PLANDIJRAPM C0..wAsHlNa'r0N, D. cv

par

JOE-IN I. NEEDHAM, OF BAYONNE, NEVZ JERSEY, ASSIGNOR, BY MESNE ASSIGNMENTS, TO THE LAMSON COMPANY, 0F NEWARK, NEW JERSEY, A CORPORATION OF NEW JERSEY.

PNEUMATIC-DESPATCH-TUBE APPARATUS.

Patented July'ZQ, 1915.

Application filed. June 29, 1910. Serial No. 569,439.

To all whom it may concern Be it known that 1, JOHN T. NEEDHAM, asubject of the King of Great Britain, a citizen of Canada, and resident of Bayonne, in the county of Hudson, State of New Jersey, have invented certain new and useful Improvements in Pneumatic-Despatch-Tube Apparatus, of which the following is a complete specification.

The main object of this invention is to provide a pneumatic despatch tube apparatus wherein a single transmission tube leads from a number of outlying stations to a central station, and provided with a car rier receiving terminal at each of said outlying stations, a plurality of return tubes extending from said central station, to the outlying stations. In the operation of such a system, carriers may be placed in the transmission tube through any one of the receiving terminals on the transmission tube, and carried through the tube to the central station. The carriers from the central station are distributed in the outgoing tubes to be returned to their respective stations. In tube systems of this general character heretofore designed and covered by my prior applications for patents, the carriers are drawn through the transmission tube to the central station and forced from the central station to the outlying stations, suitable means being provided to connect the airpressure pipe to any one of the outgoing transmission tubes. In the present application the carriers are forced through the single transmission tube and are sucked or drawn through the return tubes, the receiving ends of the return tubes being open at all times.

A further object of the invention is to connect the pressure side of the air blower or pump to the single transmission tube and the exhaust side thereof to the return tubes.

Another object of the invention is to provide means whereby the suction side of the blower may be successively connected to each of the return tubes so that air will be drawn first through one of said tubes for a predetermined time, and through another tube and so on throughout the entire series tail vertical sectional view of the receiving end of one of the tubes 10. Fig. 2' an enlarged View of the blower, motor, and the valve operating mechanism; Fig.3 a vertical. sectional view through one of the pneumatic switches of the valve operating means; Fig. i a transverse sectional view of the vacuum valve operating means; Fig. 5 a similar view of the pressure actuated valve opening means; Fig. 6 a longitudinal sectional view of one of the valves taken on the line VIVI of Fig. 5; Fig. 7 a side elevation of one of the terminals in the transmission tube; iFig. S a-transverse sectional" view thereof; and Fig. 9 a vertical sectional view of one of the vacuum delivery terminals at the outlying stations.

Referring to the various parts by numerals, l designates the transmission tube which leads from the outlying stations to the centralstation' and is connected at said station with a delivery chute 2 which may be of any suitable construction. The distant end of this'transmission tube is connectedto the pressure side of a blower This transmission tube is provided at suit able points with carrier receiving terminals at, each of said terminals consisting of a rotatable. sleeve 5 formed with cut-out portion 6 which is adapted to register with a similar cut-out portion 7 in the transmission tube. It is manifest that by rotating the-sleeve in the proper direction the solid portion thereof may be brought in position to cover the opening 7 in the trans mission tube. Suitable stops 8 are provided, adapted to be. engaged by shoulders 9 on the sleeve to stop the sleeve in position to cover or uncover the cut-out portion 7 of the transmission tube. A terminal closure ofthis construction will prevent the escape of the air under pressure in the transmission tube, and said air Will not tend to open the closure device.

A series of return tubes 10 extend from the central station to a point adjoining each of the receiving terminals at. These return tubes are open at their central station ends, and are connected to delivery terminals ll at the outlying stations. These terminals each, consists of the delivery pipe 12 arranged to deliver the carriers through the hinged doors 13 and the exhaust pipes let whichare connected to said heads and ar the delivery pipe 12. Each of the pipes 14 is connected to the main suction pipe 15 which is connected to the suction side of the blower 3. At the junction of the pipes 14 with the main suction pipe 15 is arranged a pneumatically controlled valve.

In the system illustrated in Fig. 1 there are shown four return tubes 10, and conse quently four exhaust tubes 14, and four controlling valves between said tubes 14, and four controlling valves between said tubes and the main suction pipe 15. Two of these valves 16 are pressure operated, the other two, 16 being operated by suction. The pressure operated valves consist of a sliding valve 17 connected to a valve rod 18 and normally held in closed position by a spring 19. The valve rod 18 is connected to a diaphragm 20. Theinterior of the diaphragm chamber is in communication with a small pipe 22. The valves 16 which are operated by suction are constructed exactly as the pressure valves, except that the position of the diaphragm in the diaphragm chamber is reversed, as shown in Figs. 4 and 5, the diaphragm chamber being in communication with the small pipe 23. One of the pipes 22 and one of the pipes 23 are connected to a valve operating pipe 24, the other pipes 22 and 23'being connected to a similar operating pipe 25. These pipes 24 and 25 lead to a pneumatic switch device 26. This switch device consists of two pneumatic switch arms 27 and 28, each of said arms being formed with a hollow hub 29 in communication with one of the pipes 24 or 25. Connected to this hollow hub is a tubular arm 30 which at-its free end is formed with two.

openings

31 and 31 The switch device 26 is provided with two channels 32 and 33.

Ports

34 and 35 are forme'd'in the device 26 and open into the channel 32 while ports 36 and 37 open into the channel 33. In Fig. 2 of the drawings the switch arm 27 is in position to bring its port 31 into register with the port 37 of the channel 33 while the port 31 of said switch arm is out of register with the port 35 of channel 32.- The channel '32 is connected bya pipe 38 with the main suction pipe 15, and the channel 33 is connected by a pipe 39 with the pressure pipe 1. It is, therefore, clear that when the motor is in operation air will be sucked from thepipe 38 and channel 32, and will be forced into pipe 39 and channel 33. 'In the position of the switch arm 27 shown in Fig. 2 air will be forced through the pipe 39, channel 33, port 37 and registering port 31 of the switch arm, thence through the switch arm and its hub into pipe 24. From pipe 24 air will pass into the pipes 22 and 23 connected therewith, and thence into the diaphragm chambers. As one of the diaphragm chambers is connected with a pressure operated valve and the other with a vacuum or suction valve, only the pressure valve will be operated. It is, therefore, clear that the valve 16 will be operated when air under pressure is admitted to pipe 24, thereby opening the connected pipe 14 to the main suction pipe 15 so that air will be drawn through one of the outgoing tubes. When either of the switch arms 27 and 28 is shifted to bring its port 31 over either the port 34 or port 35 air will be drawn from the connected pipe 24 or 25 through the pipe 38. The result of this is that the suction valve connected tosaid pipe 24 or 25 will be operated, thereby opening the valve 16 and placin the connected pipe 14 into communication with the main suction pipe 15.

In order to operate the pneumatic switch arms 27 and 28 Tprovide rotatable switch

operating devices

40 and 41, said devices being mounted on a shaft 42 driven through a worm gear 43 which receives its motion from a worm 44 on the shaft of the motor 45. Each pneumatic switch arm is provided with an operating finger 46 which projects into the path of cams 47 and 48 on the

switch operating disks

40 and 41. The cams 47 are lower than the cams 48, and the cams on one disk are arranged perpendicularly to the cams on the other disk, and the cams on each disk are arranged at diametrically opposite points. By this means said cams will operate alternately, that is to say, when cam 47 of disk 40 is in engagement with the operating finger 46 of switch 27 the cams of disk 41 will be out of contact with the finger 46 of the switch 28. By this means only one

valve

16 or 16 will be operated at any one time so that only one return tube will be connected to the main exhaust tube 15 at any one time. It is also clear that during one revolution of the shaft 42 all of the return tubes will be connected in succession to the main exhaust tube,15, this operation being repeated for each revolution of the shaft 42 as long as the motor remains in operation. One great advantage of this arrangement is that carriers may be dropped into the receiving ends of the return tubes as fast 'as may be desired, said carriers being drawn through the tubes when the proper valve is operated to connect the main exhaust tube to the return tube in which carriers have been placed. This formsa very convenient and eiiicicnt arrangement and permits the central oflice operator to handle a great many carriers and to distribute them in a great many return tubes. There are no doors to be opened or closed; there is no switch device of any kind to be operated, the clerk or attendant giving his entire time to the business of handling the carriers and their contents, and placing the carriers in the open ends of the return tubes for their return to their proper outlying stations. Eachswitch arm is formed with suit able slides 49 which are adapted to cover the ports 34-, 35, 36 and 37 when said ports are not in register with the ports in the switch arms.

The motor is connected by a belt with the operating shaft of the blower 3. It will, or" course, be understood that any form of blower may be used, and that it may be connected in any suitable manner with the motor. It will also be understood that any number of switch arms 27 and 28 may be employed, the switch operating mechanism being modified to operate said arms in succession, and while I have shown only two of said arms operating four valves, I do not wish to be limited in this respect.

I have found that an apparatus constructed as described is so economical in the use of electric power and operates with such a low air pressure in the tubes that the motor and blower may be operated at a low .cost in installations where the use isquite constant during the working hours. In installations where it is probable that the use of the apparatus will be, to a certain extent, intermittent I provide, in order to effect a saving in the expenditure of electric power, an automatic motor starting and stopping means adapted to be operated from each of the receiving terminals in the transmission tube, and also from each or the receiving-terminfals atthe centrals'tation or cashiers desk. To this end I provide at the receiving terminals 4t a pair of contacts 51 which are adapted to close a battery circuit through an electro-magnet 52. These contacts are adapted to be brought into engagement by means of a cam 53 carried by the terminal door 5, as shown in Fig. 8. It will thus be seen that when any one of the doors of the terminals i is opened the magnet circuit will be completed through the adjoining contacts. Adjacent each of the receiving terminals 10 at the central station is mounted a pair of contacts 5% whichare adapted to be brought into engagement with each other by means of an arm 55 connected to pivoted trigger 56 which projects into the receiving terminals 10 and normally lies in the path of the inserted carrier. It will thus be seen that when a carrier is placed in any one of the receiving terminals 10 to be transmitted to an outlying station the magnet circuit will be completed through the adjoining pair of contacts.

In a convenient position near the motor is arranged a pneumatically operated motor controlling apparatus. This controlling apparatus consists of a main diaphragm chamher 57 in which is arranged a main diaphragm 58. Connected to this chamber is an air exhaust pipe 59, said pipe being connected to the exhaust tube15. It will, of

course, be understood that the diaphragm chamber 57 is to be locatedin a convenient position withrespect t0 the motor in order that the air will be properly and promptly exhausted from said chamber. The chamber 57 is provided with an inlet valve 60 which is connected to and operated by lever 61. On this lever is secured an armature which is adapted'to be attracted by the electromagnet 52, so that when the magnet circuit is completed the lever 61 will be swung on its pivot to open the inlet valve 60 of the dia-' phragm chamber, and thereby destroy the vacuum therein.

A pair of contacts 62 is arranged close to the end of the lever'61, one 01": said contacts being adapted to be engaged by the said lever, when the inlet'valve 60 is opened, to close the circuit through a suitable motor starting solenoid 63. When said solenoid circuit is closed the motor circuit is closed through contacts 64: and the motor will continue to drive the blower until the solenoid circuit is interrupted. Connected to the main diaphragm 58 is a pin 65 which normally engages a pair of contacts 66 arranged in a second solenoid circuit. In said second solenoid circuit is arranged a pair of contacts 67 which are adapted to be brought to gether bythe core 68 of the solenoid when said core is moved by the solenoid coil.

The operation of the motor controlling means maybe briefly described as follows: When any one of the terminal doors 5 is opened the electro-magnet circuit is closed and the said magnet energized thereby moving the lever 61 to open the valve 60. of the main diaphragm chamber. The movement of this lever closes the solenoid circuit through the contacts 62, thereby completing the motor circuit through contacts 64 and starting the blower to draw air through the suction pipe 15 and to force it through the delivery tube 1. hen the valve 60 is opened the diaphragm 58 will move inwardly under the influence of the spring 65, thereby bringing the contacts 66 into engagement to close the sec nd solenoid circuit. By this means the motor circuit will be held closed through the contacts 67 and 66 and the contacts 62 may sep arate without affecting the solenoid circuit. The motor will now continue to operate until a sufiicient degree of vacuum has been produced in the maindiaphragm chamber through the pipe 59 to return the diaphragm 58 to its normal position and thereby sepa-' rate contacts 66. As soon as said contacts are separated the solenoid circuit is interrupted and the motor circuit broken at the contacts'64. It will, of course, be understood that the same cycle of operations takes place when a carrier is inserted in any one of the receiving terminals 10, the electro-maguet circuitbeing then completed through one of the pairs of contacts 54. After'the carrier &

through the terminal 10, or the door 5 has been closed, the contacts 54, or the contacts 51, will separate, thereby deenergizing the electro-magnet and permitting the valve 60 to close. Vacuum will then be produced in the diaphragm chamber through the pipe 59, as previously described, and the length of time required to develop the proper degree of vacuum may be regulated by a suitable valve 59 arranged in the pipe 59. This type of motor controlling apparatus is disclosed in my pending application, Serial No, 495,127, filed May 10, 1909. c

Having thus fully described my invention what I claim as new and desire to secure by Letters Patent is 1. A. pneumatic despatch tube apparatus comprising a transmission tube leading to a central station, a plurality of rece ving terminals in said tube each of said terminals being located at an outlying station, a series of return tubes from said central station to said outlying stations, a blower, means connecting the pressure side of said blower to the outer end of the single transmission tube leading to the central station, means operating to automatically connect and discon nect the outer ends of the return tubes in succession to the suction side of the blower, and means for operating said blower.

2. A pneumatic despatch tube apparatus comprising a single transmission tube leading to a central station, a plurality of receiving terminals in said tube, each of said terminals being located at an outlying station, a series of return tubes leading from the central station to said outlying stations, said return tubes being open at their central station ends, a blower, means connecting the pressure side or" said blower to the outer end of the single transmission tube, a suction tube connected to the suction side of said blower, and means operating automatically to open and close communication be tween said suction tube and the outlying ends of the return tubes. 7

3. A pneumatic despatch tube apparatus comprising a single transmission tube leading to a central station, a plurality of receiving terminals in said tube, each of said terminals being located at an outlying station, a series of return tubes leading from the central station to the said outlying stations, a blower, an exhaust tube connected. to the suction side of the blower,'means connecting the pressure side of the blower to the single transmission tube, and means for successively placing the outer ends of the return tubes in communication with the suction tube.

4. A pneumatic despatch tube apparatus comprising a single transmission tube leading to a central station, a plurality of receiving terminals in said tube, each of said terminals-being located at an outlying station, a series of return tubes leading from the central station to the said outlying stations, a blower, an exhaust tube connected to the suction side of the blower, means connecting the pressure side of the blower to the single transmission tube, a motor, and means operated by the motor for successively placing the outer ends of the return tubes in communication with the suction tube.

5. A pneumatic despatch tubeapparatus comprising a single transmission tube, a plurality of terminals in said tube, each of said terminals being located at an outlying station, a series of return tubes, a blower, means connecting the pressure side of the blower to the single transmission tube, a suction tube connected to the suctionside of the blower, valves controlling communication between the suction pipe and the outer ends of the return tubes, and means for successively operating said valves to place said return tubes in communication with the suction pipe.

6. A pneumatic despatch tube apparatus comprising a single transmission tube, a plurality of terminals in said tube, a series of return tubes, a blower, means connecting the pressure side of the blower to the single transmission tube, a suction tube connected to the suction side of the blower, pneumatically operated valves controlling communication between the suction pipe and the outer ends of the return tubes, and means for successively operating said valves to place said return tubes in communication with the suction pipe.

7. A pneumatic despatch tube apparatus comprising a single transmission tube, a plurality of terminals in, said. tube, a series of return tubes, a motor, a blower, means connecting the pressure side of the blower to the single transmission tube, a suction tube connected to the suction side of the blower, valves controlling communication between the suction pipe and the outer ends of the return tubes, and means operated by the motor for successively operating said valves to place, said return tubes in communication with the suction pipe.

8. A'pneumatic despatch tube apparatus comprising a single transmission tube, a plurality of terminals in said tube, a series of return tubes, a blower, means connecting the pressure side of the blower to the single transmission tube, a suction tube connected to the suction side of the blower, a motor for operating the blower, pneumatically operated valves controlling communication between the suction pipe and the outer ends of the return tubes, and means operated by the motor for actuating said valves.

9. A pneumatic despatch tube apparatus comprising a single transmission tube, a plurality of receiving terminals therein, a plurality of return tubes, a blower, a motor by the motor for controlling the flow of air to and from said valves. I

10. A pneumatic despatch tube apparatus comprising a single transmission tube, a plurality of terminals in said tube, a series of return tubes, a suction tube, a blower, means connecting the pressure side of the blower to the single transmission tube, means connecting the suction tube to the suction side of the blower, a pneumatically operated valve controlling communication between the outlying end of each of the returntubes and of the suction tube, some of said valves being operated by suction, and others by pressure, and means for connecting the pressure and suction sides of the blower to said valve. 7

11. A pneumatic despatch tube apparatus comprising a single transmission tube, a plurality of terminals in said tube, a series of return tubes, a suction tube, a blower, means connecting the pressure side of the blower to the single transmission tube, means connecting the suction tube to the suction side of the blower, a pneumatically operated valve controlling communication between the outlying end of each of the return tubes and of the suction tube, some of said valves being operated by suction, and others by pressure, a valve operating pipe connected to one suction valve and one pressure valve, and means for alternately connecting said pipe to the pressure side and to the suction side of the blower.

12. A pneumatic despatch tube apparatus comprising a single transmission tube, a plurality of terminals in said tube, a series of return tubes, asuction tube, a motor, a blower, means connecting the pressure side of the blower to the single transmission tube, meansconnecting the suction tube to the suction side of the blower, a pneumatically operated valve controlling communication between the outlying end of each of the return tubes and of the suction tube, some of said valves being operated by suction, and others by pressure, a valve operating pipe connected to one suction valve and one pressure valve, and means operated by the motor for alternately connecting said pipe to the pressure side and the suction side of the blower. r,

13. A pneumatic despatch tube apparatus comprising a single vtransmission. tube, a plurality of terminals in said tube, a series of return tubes, a suction tube, a motor, a blower, means connecting the pressure side of the blower to the single transmission tube,

connected'to one suction valve and one pressure valve, a pneumatic switchfadapted to place said pipe alternately in communication with the pressure side and the suction side of the blower, and means actuated by the motor for operating said pneumatic switch.

14. A pneumatic despatch tube apparatus comprising a single transmission tube, a plurality of terminals in said tube, a series of return tubes, a blower, a motor for operating said blower, a suction pipe connected to the suction side of the blower, the pressure side of said blower being connected to the single transmission tube, a pneumatically operated valve controlling communi cation between the outer end of each of the return tubes and the suction tube, some of said valves being operated by suction and the others by pressure, a series of valve actuating pipes, each of said pipes being in communication with one pressure actuated valve, a suction valve, a pneumatic switch for each of the valve actuating pipes, and means actuated by the motor for operating said switches to alternately connect each of the valve operating pipes to the pressure side and to the suction side of the blower.

15. A pneumatic despatch tube apparatus comprising a transmission tube leading to a central station, a plurality of receiving terminals in said tube, a series of return tubes from said central station to outlying stations, a blower, means connecting the pressure side of said blower to the single transmission tube leading to the central, sta-' tion, means connecting the outer ends of the return tubes to the suction side of the blower, a motor for operating said blower, and a timing means to permit said motor to operatea predetermined time.

16. A pneumatic despatch tube apparatus, comprising a transmission tube leading to a central station, a plurality of receiving terminals in said tube, a series of return tubes from said central station to outlying stations, a blower, means connecting the pressure side of said blower to the single transmission tube leading to the central station, means connecting the outer ends of the return tubes to the suction side of the blower, a motor for operating said blower, means at each receiving terminal for starting said motor, and means for stopping said motor after a predetermined time.

terminals in said tube, a series of return tubes from said central station to outlying stations, a blower, means connecting the pressure side of said blower to the single transmission tube leading to the central station, means for intermittently connecting the outer ends of the return tubes to the suction side of the blower, means for operating said blower, and means for stopping said blower after all of the return tubes have been connected to the suction side of the blower.

18. A pneumatic despatch tube apparatus comprising a single transmission tube, a pluralityof terminals, therein, a series of return tubes, a suction tube, a blower, a motor. for operating said blower, means connecting. the outer end of the transmission tube to the pressure side of the blower and the suction tube to the suction side of the blower, a valve for controlling coinmunication betweenthe outer end of each return tube and the suction tube, means actuated by the motor for operating said valves in succession, means at each receiving terminal for starting the motor, and means for stopping the motor after all of the said valves have been operated. V

.19. A pneumatic despatch tube apparatus comprising a single transmission tube, a plurality of terminals in said tube, a series of return tubes, a blower, a motor for operating said blower, a suction pipe connected to the suction side of the blower, the pressure side of said blower being connected to the single transmission tube, a pneumatically operated valve controlling communication between the outer end of each of the return tubes and the suction tube, some of said valves being operatedby suction and the others by pressure, a series of valve actuating pipes, each of said pipes being in communication with one pressure actuated valve and one suction valve, a pneumatic switch for each of the valve actuating pipes, means actuated, by the motor for operating said switches to alternately connect each of the valve operating pipes to the pressure side and to the suction side of the blower, .1neans at each receiving terminal for starting the motor, and means for stopping the motor when allot the valves have been operated.

20. A pneumatic despatch tube apparatus comprising, a single transmission tube, a plurality of terminals in said tube, a series of return tubes, a suction tube, a blower, means connecting the pressure side of the blower to I the single. transmission tube, means connecting the, suction tube to the suction side of the blower, pneumatically operated valves controlling communication 21. A pneumatic despatch tube apparatus comprising a single transmission tube, a plurality of terminals in said tube, a blower, means connecting the pressure side of said blower to said single transmission tube, a seriesof return tubes, a suctiontube connected to the suction side of the blower, a valve controlling communication between the outer end of'each return tube and the suction tube, means for operating said valvesin succession whereby the outer ends of the return tubes will be in succession in communication with the suction tube, and a pneumatically operated timing means for said motor.

22. pneumatic despatch tube apparatus comprising a series of tubes, a blower, a motor for operating said blower, means operated by the motor for successively connecting the suction side of the blower to the ends of said tubes.

23. A pneumatic despatch tube apparatus comprising a series of tubes, a blower, a motor for operating said blower, means operated by the motor for successively connecting the suction side of the blower to the ends of said tubes, and a timing means for the motor.

24:. A pneumatic: despatch tube apparatus comprising a series of tubes, a blower, a motor for operating said blower, means operated by the motor for successively connecting the suction side of the blower to the ends of said tubes, and a pneumatically operated timingmeans for said motor.

25. A'pneumatic despatch tube apparatus comprising a series of tubes, a blower, amotor for operating said blower, means operated by the motor for successively connecting the suction side of the blower 'to the ends of said tubes, and a timing means to stop said motor when all of the outlying endsof the return tubes have been in succession connected to the exhaust side of the motor.

26. y A pneumatic despatch tube apparatus comprising a transmission tube leading to a central station, a plurality of receiving terminals in said tube, a series of return tubes from said central station to outlying stations, a blower, means for connecting the pressure side of said blower to the outer end of the single transmission tube, automatically operating means connecting the outer ends of the return tubes in succession to the suction side of the blower, a motor for operating said blower and a timing means for the motor.

27. A pneumatic despatchtube apparatus comprising a series of tubes, a blower, a motor for operating said blower, means for tubes have been connected to the suction side of the blower.

29. A pneumatic despatchtube apparatus comprising a serles of tubes, a blower, a motor for operating said blower, means for successively connecting the suction side of the blower to the tubes and means to stop the motor aft r all of said tubes have been connected to the blower.

30. A pneumatic despatch tube apparatus comprising a single transmission tube, a plurality of terminals in said tube, a series of return tubes, a blower, means connecting one side or" said blower to the single transmission tube, means for connecting the other side of said blower to the ends of the return tubes in succession, a blower operating mechanism, and means for stopping the blower operating mechanism after all of said return tubes have been connected to the blower.

31. A pneumatic despatch tube apparatus comprising a single transmission tube, a plurality of terminals in said tube, a blower,

means for connecting one side of said blower to said single transmission tube, a series of return tubes, a blower operating mechanism and means operated from said blower operating mechanism to control communication between the other side of the blower and the return tubes.

32. A pneumatic despatch tube apparatus comprising a single transmission tube extending from a central station to an outer station, a plurality of terminals in said tube between its outer end and the central station, a blower, the pressure side of the blower being connected to the outer end of the single transmission tube, a series of return tubes extending from the central station to the outlying stations, a blower operating mechanism and means operating to connect the suction side of the blower to and disconnect it from the outer ends of thereturn tubes in succession.

38. A pneumatic despatch tube apparatus comprising a single transmission tube extending from a central station toan outer station, a plurality of terminals in said tube 1 between its outer end and the central station,

a blower, the pressureside of the blower being connected to the outer end of the single transmission tube, a series of return tubes extending from the central station to the outlying stations, a blower operating mechanism, means operating to connect the suc tion side of the blower to and disconnect it from the outer ends of the return tubes in succession, a timing means for the blower operating mechanism, and means operating upon the insertion of a carrier to start the timing means.

34. Apneumatic despatch tube apparatus comprising a series of return tubes extending from a central station to outlying stations, a blower, a motor for operating said blower and means for successively connecting and disconnecting the suction side of the blower to and from the outlying'ends ofsaid return tubes in succession.

35. A pneumatic despatch tube apparatus comprising a series of return tubes extending from a central station to' outlying stations, a blower, a motor for operating said blower, means for successively connecting Witnesses:

F. R. MILLER, WM. R. DAVIS.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

- Washington, .D. C.

JOHN T. NEEDHAM.