US1615932A

US1615932A - Controlling apparatus for pneumatic-dispatch systems

Info

Publication number: US1615932A
Application number: US73357A
Authority: US
Inventors: James T Cowley
Original assignee: Lamson Co
Current assignee: Lamson Co
Priority date: 1923-07-12
Filing date: 1925-12-05
Publication date: 1927-02-01
Anticipated expiration: 1944-02-01

Description

Feb. 1, 1927.

J. T. COWLEY CONTROLLING APPARATUS 'FOR PNEUMATIC DISPATCH SYSTEMS 4Original Filed July l2, 1923 Patented Feb. 1, 1927,.

JAMES T. COWLEY, @E SYBAGUSE, YORK, ASSTGNGF; EJE T Ol? SYRACUSE, NE'W A. CDRPORA CONTROLLIHG APPARATUS FR PrlEUltAlC-DSATCH SYSTEMS.

original appueanon inea muy is, ieee,

Serial No. 651,065, Patent 11o. 1586.249, dated .Tune 1, 1926.

Divided and this application filed December 5, 153/25. Serial No. 73,357.

This invention pertains to powerI control apparatus for pneumatic dispatch systems and more particularly to automatic apparatus of the `general type disclosed in the patent to Libby 968,576; dated august 3G, 1910, wherein the opening and closing` or a main valve is determined by fluid motor means actuated by pressure variations in the transmission line` the pre-sent application beinn a division ot my application Serial No. 651,065 ttor controlling` apparatus for pneumatic dispatch systems, tiled July 12, 1923, and patented lune 1, 192%.llumber 1586.219.

rlhe principal objects of the present invention are to provide improved controlling' apparatus of the above type which is sensitively responsive to slight pressure variations in the transmission tube incident to the introduction of a carrier therein or its delivery therefrom, to provide an arrangement such that the slight movement of a pneumatic,` tor example a 'flexible diaphragm eX- posed to transmission tube pressure which occurs when a carrier is introduced into the transmission tube. will initiate the full opening; movement ot the main valve; to provide means independent ot the aforesaid pneumatic responsive to slight drop in pressure in the transmission line `tor initiating the closing' ot the main valve; to provide for the rapid restoration of parts to normal position after the discharge oit the'last carrier from the transinission tube; and in general to provide an apparatus ot simple and reliable character having' few moving' parts and which occupies al minimum ot space.

.ln the aceompanyin n` drawings one desir'- able embodinient of the invention is disclosed by way oit example, and in such drawings.

Fig. 1 is a fragmentary vertical section to enlarged scale, such section heine` taken on the center line o1 the main valve and showing the parts in their normal position, the main valve being; closed; and

Fig'. 2 is a diagrammatic view illustrating a preferred arrangement of electrical circuits employed in the operation ot the controllinov apparatus. Y

lic'tei to the drawings the numeral 1 indicates the main outer casing` ot the apparat-us such casing; beine hollow and providiupr the chamber 2 wl'iich is connected in usual manner by means oit a suitable pipe,

not shown, to the suction drum or exhauster ot the dispatch system.

Within the casing;` 1 an inner casing` 3 'Inrnishes an inner chamber el, which communicates by means of a passage with the transmission tube7 not shown.

The upper and lower walls of the inner casing 3 are provided with aligned valve apertures which are norn'lally closed bythe spaced heads 7 and 8 oit a ba anced main valve 6. A smallk passage 9, here siiown as formed in the head S of the main valve, provides for the movement of a small quantity of air commonly reterred to as the minimum flow, from the chamber l tok theV outer chamber 1. rihe valve 6 is furnished with a stem 10 suitably `guided in an openingr in the upper wall 11 ot the outer housing or casing 1.

The wall 11 is furnished with an outstanding); tlann'e portion providing' a seat for 'the edges oit a lflexible diaphragm 12 which is clamped to the seat by a cover member 13,k The diaphragm 12 separates the space between 4the cover 13 and the wall 11 into upper and lower chambers 141 and 15 respectively. The chamber 1 communicates with the chamber 1l by means of a passage 16 which opens through the diaphragm 12 at the point 18.

The central part of the diaphragi'ni12`r is clamped between

plates

20 and 21 which are secured to the stem 10 by means of a nut 22. A rod 23, forming an extension ot the stem of thevalve 6, is provided with a nut 24k at its lower end and bears against the nut 22 on the upper end of the stem 10. li desired the extension 23 may torm an integral continuation of the stem 10. A passage 1GaM extends axially along the stem 10 and its continuation 23 and opens laterally with chamber 141 and at its lower end is provided with a` lateral branch 15a open-inn' at the outer surface of the stem but norm ally closed by the wall member 11.

A coil spring` encircles the rod 223 and bears at one end airainsiv the nut 211. The upper end of the rod 23 passes throughv a guide opening in a gland 26 having' threaded engagement with a suitable opening in the cover 13 and the upper end of the spring` 25 bears against the inner surface of this gland.

The cover 13 supports an auxiliary pneumatic motor comprising` an upstanding an- Crt) nular flange 27, here shown as integral with the cover 18, and a cover member 28 suitably secured to the flange 27 and which clamps the edges of a diaphragm 3l against the upper edge of the flange 27. This diaphragm 31 separates the space between the cover member 2S and the member 13 into upper and

lower chambers

29 and 30 respectively. The lower chamber 30 is provided with a small port 32 leading to the outer atmosphere while the upper chamber 29 is connected by means of a pipe 33 to the transmission line so that transmission line pressure is always maintained in the chamber 29. The diaphragm 31 is provided with a stem 34 which is guided to slide in a gland 36 and which is held in normal position by means of a spring1 35 encircling the stem and bearing against the inner surface ot' the gland.

The cover 13 of the main motor is furnished with an upstanding boss 37 provided with a guide bore 38 parallel to the stein 10 of the valve and which receives a sliding bar or rod 89. A spring` 40 bears against the surface of the bar or rod 30 and tends frictionally to retain the latter in whatever position it may be placed. This rod 39 is furnished with axially spaced stops for example, the upper and lower ends of elongate slot 4l in its outer surface. and is provided at its upper end with a taper cani finger or plug 42. This plug and preferably the entire bar 89 is made of some suitable insulating material.

The upper end of the post or stem eXtension 23 is provided with a bracket 44, one end of which is disposed within the slot or recess 41 in the rod 39. The bracket 44 is also furnished with an upstanding part 45 to which a cam bar 46 is secured.

The cam bar 46 is furnished with an inclined cam surface 46a at its upper end.

The main housing 1 is provided with a lateral extending' hollow boss 47 providinga cavity 48 which communicates freely with the chamber 15. This cavity 48 communicates with the outer atmosphere through a port defined by an annular valve seat with which a valve 49 cooperates. This valve is normally7 closed and is furnished with a stem 50 constituting or connected to the core of a solenoid 51.

One terminal of the solenoid windings is connected by a wire 52 to one pole of a battery 53 or other sui-table source of electrical energy. The other pole of this battery is connected by wires 54 and 54n with a resilient arm 55 suitably mounted upon an insulating block 55a'. The free extremity of this resilient arm is arranged immediately above the upper end of the stem 84 of the diaphragm 31 and is furnished with an electrical contact element 56. A cooperating' contact element 57 is carried by a iiexible arm 58 parallel to the arm 55 and also mounted upon the block 55a. The arm 5S is connected by a wire 59 to a wire 60.1unning to the other terminal of the solenoid windings.

The wire 60 is also connected by means of a wire to a resilient arm 6l suitably supported at one end upon aninsulating support and furnished at its other end with the contact member 63. This contact member normally engages a cooperating contact member 64- carried at the lower end of a second resilient arm 62 which in turn is supported at its upper end upon an insulating support. The lower ends of the arms 61 and 62 diverge from each other and are disposed in'nnediately above the upper end of the cam member 42 in such a way that upward movement of the post or bar 39 causes the cam 42 to enter between the contacts 63 and 64 and to separate the latter.

The resilient supporting arm 62 is connected by a wire 66 to another resilient arm 67 supported upon an insulating block 67a. The lower end of the arm 67 carries an electrical contact 68 and the arm 67 is provided at a point intermediate its length with a cam follower block 08a having an inclined cani surface engageable with the cam surface 476FL of the cani bar 46. The contact 68 cooperates with an opposed contact GT carried by a resilient arm 'TO also mounted upon the block 67a. This arm 70 is connected by a wire 71 to the wire 54.

i The lower wall of the chamber 15 of the main motor is furnished with a small port 8O leading to the outer atmosphere. l valve 81 is adapted to close this port. This valve 81 is carried by a lever 82 pivotally supported at 83 and provided with a counterweight 84 which tends to swing the lever so as to close the valve 9,1 against the port 80. A rod S5 preferably secined to the lower plate 2l passes through the port S6 and contacts with the valve 81. normally holdingthe valve open in opposition to the weight 84. lllanifestly the rod 85 might alternatively be secured to the valve or might be independent of both the valve and plate and suitably guided for transmitting movement from the plate to the valve.

In the arrangement thus provided the electrical: circuit through the solenoid 51 comprises two loopsthe wires 54. 7L 67. 66, 65. 60 and 52 constituting one loop7 and the

wires

54, 54, 59 60 and ionstit-utingi the other loop. The contacts 63 and 64 form a normally closed switch in the first named loop of the circuitand the contacts 66 and 69 constitute a normally open switch in the same loop. The contacts 56 and 5T form a normally open switch in the other loop of the circuit.

The operation of the device is substantially as follows: Vit being understood that lll? remesa the parts normally occupy substantially the positions shown in Fig. 1 when no carrier is in the transmission tube.. their a carrier is introduced into.- the tube the pressure in the latter drops slightly below normal due tothe cutting ott ot the minimum tloiv, whereupon. the diaphragm 12 immediately 'liexes upwardly to a slight extent but not sutlicient to open the main valve 6. This slight movement is enough to cause the cam member 46 to press resilient arm GT to the left as viewed in Fig. 1 so as to bring' the contact 68 into engagement With the contact 69.

rThe circuit is thus closed through the first loop as above described, thus energizing` the solenoid and thereby lifting the. valve t9 to admit atmospheric. pressurel to the cha-mber 15. This permits thel diaphragm `12 to rise freely to its full extent. thu-s opening the main valve 6 and connecting the suction drum with the transmission tube. This causes a marked decrease in pressure in; the transmission tube resulting'- in a rapid tloiv ot' air sutlicient to move the carrier toivard its. destination. This relatively large decrease in pressure in the transmission tube is transmitted througlfi the pipe to the chamber 29 ot' the auxiliary motor and thus raises the diaphragm 31. It may be stated at this point that the spring` 35. is sutliciently strong to prevent upward movement of the diaphragm 31 except when the main valve is at least partially open and a carrier is in the tube As the diaphragm 3.1 rises it brings the contacts 56 and 5T into engagement. thus closingI the circuit through the second loop comprisingl the Wires 59 and 54a.. This action takes place jlust prior to the full. opening ot the main valve. As the main valve approaches its fully open position the arm 4:4 comes into engagement with. the, upper end of the recess 'stl in the rod 39 and moves the latte-r up su'lticiently to insert the cam member t2 between the contacts (53 and 641, thu-s breaking the circuit which. was closed by engagement ot the contacts 68' and 69, but since the

contacts

56 and 57 have previously been engaged the tloiv ot current through the solenoid is not upward.

dien the last carrier disclliarges .trom the transmission tube the pressure in the latter increases slightly and the spring 35 immediately restores the diaphra-gn'i 31 to its non nia-l position. This breaks the circuit through the solenoid since the

contacts

56 and 57 immediately separate andas the solenoid is cle-energized the valve. L9- closes thus cutting oit atmospheric pressure from the chamber 15. As the main valve opened, the port 15a lifted above the upper surface ot the Wall 11 thus providing a small passage between the chamber 15 and the chamber 141. Then leading to the passage 1()u was which is tapped in the chamber' 15 to be expelled as the main val-ve comes to its fully closed position.

is the diaphragm 1Q moves downwardly the tinger elet engages the loiver end of the recess 41 in the member 39 and thus restores the member 39 to its. normal position permitting the contacts 63 and Getto re-engage While at the same time the cam bar @t6 moves downwardly and permits the contacts 68 and (39 to separate. The parts are thus restored to` their normal position ready tor a subsequent operation.

I claim:

1. Power control apparatus torpneumatic dispatch systems comprising` a motor, electro-magnetic means tor controlling the operation of the motor, and a circuit closer and a circuit breaker both actuated by the motor.,

2. Power control apparatus tor a pneumatic dispatch systen'i having a transmission tube, said apparatus comprising a pneumatic motor having a reciprocable element, acontrolling valve for the motor, an electromagi'ietic device tor moving the valve, a normally open` electrical circuit including saidl electro-magnetic device'. a circuit closer operable by the reciprocable element ot the motor for closing said circuit as the reciprocable element liegins its movement iuone direction and a circuit breaker also operable by the recip-rocable ele-ment ot the motor tor opening the circuit as the reciprocable element approaches the limit ot its movement in said direction.`

3. Power control apparatus tor a pneumatic dispatch system havinga transmission tube. said apparatus comprising` a pneumatic motor havin-g` a reciprocaliile element, a normally closed controlling valve tor the motor, an electro-magnetic device :tor opening the valve. a norn'ial-ly open electrical circuit including said electro-magnetic device, a. circuit closer operable by the reciprocable elementot the motor .tor closiimsaid circuit as the reciprocable element begins its movement in one direction and a circuit breaker also operable by the reciprocable eiement ot the motor tor opening the circuit as the reciprocable element completes its said move-- ment, and means tor short circuiting` said circuit breaker whereby to maintain a Closed circuit througl'i the electro-magnetic device so loue as a carri-.ef remains in the tube'.

4t. Power control apparatus tor a pneumatic dispatch system having a transmission tube and means tor creating a carrier propelling air dow therein. said apparatus comprising a motor having a reciprocating elenient. electro-maznetic means for controlling the operation ot the motor, an electrical circuit including' said electrai-magnetic device. a normally open switch device in circuit. a normally closed switch device in said circuit. means actuable by the reciproci ile element ot the motor at it moves in one direction io close the nonmall;Y open switch, to hold it closed during the remainder ot' said movement oil the reciprocable element, and to open the normally closed switch, and independent means 'tor maintaining' a clo l circuit througli the electromagnet-ic dei ice so lone' as a carrier remains in the transmission tube.

5, Power control apparatus tor a pneumatic dispatch system having a transmission tube and means for creatine; a carrier prolll) pelling air flow therein. said apparatus comprising` a motor having` a reciprocating element, elec lro-mag'netic means 'for controlling the operation ot the motor, an electrical circuit including' said electro-magnetic device, a` normally open switch device in said circuit. a normally closed snfitcli device in said circuit, means a-ctuable by the reciprocable element of the motor as it moves in one direction to close the normally open switch and to keep it closed during the remainder of the movement of the reciprocating element, means operative by the motor for opening` the normally closed switch as said reciprocatingelement nears the end ot its stroke, and means Ytor maintaining a closed circuit through the electro-magnetic device so long' as a carrier remains in the transmission tube.

G. Power control apparatus of the class Vdescribed comprising' a transmission tube, a main valve. a reciprocable stem tor the valve, a fluid motor for reciprocating the valve stem. a control valve for the motor, an electro-magnetic device for actuating` the control valve, an electrical circuit including said electro-magnetic device. a normally open switch in the circuit. means carried by the main valve stein tor closing` said switch as the main valve begins to open and for holding said switch closed while the main valve is open. a. normally closed switch in the circuit.. means actuable by the valve stem as the valve nears its fully open position to open the latter switch, and means independent ot the main valve for maintaining a closed circuit through the electro-magnetic device so lon as a carrier remains in the tube.

7. Power control ap iarat-us of the class described comprising' a main valve. a reciprocabie stem fir the valve, a lluid motor 'for reciprocating the valve stem, a cont-rol valve for the motor, an electro-magnetic device for actuating the control valve, an electrical circuit including said electro-magnete device, a normally open switch in the circuit, a normally closed switch in the circuit, cam means act-uable by the main valve stem for closing,- the iirst switch as the main valve begins to open, other cam means for opening the other switch, lost motion connections between the latter cam means and the valve stem, and pressure actuated means independent of the main valve motor for subsequently breaking the circuit through the electro-magnetic device.

S. Power control apparatus ot' the class described compi-isiuga main valve, a reciprocable stem it'or the valve, a fluid motor for reciprocating` the valve stem, a control valve for the motor, an electromagnetic device for actuating the control valve, an electrical circuit including said electro-magnetic device, a normally open switch in the circuit, a normally closed switch in the circuit, cam means actuable by the main valve stem tor closing` the first switch as the main valve begins to open, a sliding bar parallel with the valve stem, said bar having a cam ele` ment for opening the second switch, said bar also having axially spaced stop elements, an arm carried by the main valve stem, one end ot the arm beingdisposed between said stop elements, and an auxiliary motor controlling a third switch in the circuit.

9. Power control apparatus ot' the class described comprising a main valve, a reciprocable stem 'tor the valve, a fluid motor tor reciprocating the valve stem, a control valve .tor the motor, an electro-magnetic device tor actuating the control valve, an electrical circuit including said electro-magnetic device, a switch .in said circuit comprising parallel resilient support-s, normally separated contacts carried by the supports, a cam follower bloclr secured to one ot the supports, an elongate cam bar carried by the main valve stem and engageable with said cam follower as the valve begins to open whereby to move the contacts into engagement and to hold them in engagement substantially so long as the main valve remains open, and means independent ot the main valve and its motor tor subsequently breaking the circuit through the electromagnetic device.

10. Power control apparatus for a pneumatic dispatch system comprising a main valve, a motor i'or actuating it, an auxiliary valve controlling); the motor, electro-magnetic means 'tor movingthe auxiliary valve, and a circuit including' the windings ot the elec- 'tro-inagnetic means, said circuit comprising two branches, one branch bciun provided with a normally open switch and a nor mally closed switch and-tbe other having' a normally open switch, means actuated by tbe motor tor closing;l the normally open switch and opening the normally closed switch of the first branch of the circuit, and independent means for closing the switch in the second circuit before the normally closed switch is opened.

11. Power control apparatus for a pneumatic dispatch system having a transmission tube and means for creating carrier propelling air flow therein, said apparatus comn prising a main Valve, a pneumatic for actuating it, an auxiliary Valve, a solenoid for moving the auxiliary valve, and an electrical circuit including the windings of the solenoid, said circuit having two branches, a normally open and a normally closed switch in the first branch, a normally open switch in the second branch, means actuated by the pneumatic for successively closing the normally open switch and opening the normally closed switch in the first branch of theI circuit as the main valve moves from closed to fully open position, and a fluid motor for closing, the switch in the other branch of the circuit and for keeping it closed so long as a carrier remains in the transmission tube.

12. A power control apparatus comprising a pneumatic motor having a chamber, a diaphragm forming one Wall of the chamber,

a port for admitting pressure i'iuid to the chamber, a Valve normally closing the port, and means actuable by the diaphragm for opening the valve as the diaphragm mores inwardly to decrease the normal capacity of the chamber.

13. A power control apparatus comprising a pneumatic motor having a diaphragm, a port for admitting,1 pressure fluid to one side of the diaphragm, a Valve for closing` the port, and a pin carried by the diaphragm arranged to project through the port as the diaphragm approaches its limit oll motion in one direction for opening the valve.

14C. A power control apparatus comprising,` a pneumatic motor having a pressure chamber closed at one side by a movable diaphragm, a port in the Wall of the chamber, a pivotally mounted valve cooperating' With the port, a counterweight normally closing` the valve, and a pin carried by the diaphragm arranged to project through the port as the diaphragm approaches one limit of its movement to open the valve.

Signed by me at Syracuse, New York this second day of December 1925.

i JAMES T. COVLEY.