US1332895A - Pneumatic-despatch-tube system - Google Patents

Description

C. P. HIDDEN. PNEUMMIC DESPATCH TUBE sYsEM.

APPLICATION FILED JULY 19,1916.. I

Patented Mar. 9,1920.

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- nn-iria sfrarns rnrnnfr ormoni CHARLES P. HIDDEN, OF

BROOKLINE, MASSACHUSETTS, ASSIGNOR TO TE LAMSON f COMPANY, OF BOSTQN, MASSACHUSETTS,

A CORPORATION OF NEWv JERSEY.

rnnurae'ricfnnsrATcH-TUBE ysn's'rnivr.

To all whom may concern .f

'Be 1t known' that I, CHARLES a citizen of the United States, Brookline, the county of P. HIDDEN, residing at y in Norfolk and State of Massachusetts, have invented. certain new and useful Improvements in Pneuinatic- Despatch-Tube Systems, of which the followingis a specification. i

. This i1 vention` relates to pneumatic' despatch tube apparatus andI it has for one of its principal objects the economization of power in the operation of despatch tube systems while yet insuring a proper trans mission of carriers through thetube line with practically unfailing certainty.

ln a syste-m of this general character, it ha.; also been my aim to naratus as to enable it to meet the conditions yof practice wherein it is frequently necessary to employ tube` lines of very considerable length; since obviously, the longer the tube lines to be served, the greater the liability of one or more carriers being left inadvertently in the line to the inevitalolev discomfort of the users of such apparatus and of the patrons of, for example, stores, wherein it may be used. v Y j Y Another object of my. invention, considered broadly in van aspect thereof whichis of general application to pneumatic despatch tube systems wherein variations in the load on the line affect the operation of the air current establishing means, is to prevent what l have hereinafter termed cumulative interaction between. said means and the governi-ng or controlling device therefor which acts responsively to said variations.

These andnumerous other objects of my.

invention will be hereinafter more fully considered and the novel combinations of means and elements whereby said obiects may be attained', will be moreparticularly pointed out in the claims appended hereto.

ln the accompanying drawing which forms a part hereof and in which like reference characters designate throughout the several views, I have exemplified a preferred embodiment of my invention; but as I am aware of and modifications. which maybe made herein without departing from the. spirit of the Specification of Letters Patent.

l; ay portion of said so devise the ap.

station B, whichI may,

Y station.

like parts f many changes `Patented. Mar. 9, 192.0.

invention, I desire to be limited only by the scope of said claims. Referring to the drawing: v

. Figure l is a somewhat ydiagranimatie and partially sectioned representation of a despatch tube system which involves the control of an electric motor by novel instrumentalities in combination with certain known elements which co-act with said instrumen-I talities to effect new and desirable results.

lFig. 2 is a detail of a valve shown in Fig.,

valve and its* casing ing brokenaway for purposes of illustration. Fig. 3 is av detail section of VsaidV valve;

the section being taken on the line UIQ-lll of Fig. 2; and

Fig. 4l is a ldetail section of a modification of a part of the power controlling device. I It may be stated to beginywith that while the system shown merely by way of exemplilicationis of Vthe so-called vacuum type, the invention in its broaderv aspects is by no means limited to this particular type of apA paratus. C

Considering now more particularly the construction which appears in Fig. 1a tube. lines have been shown connecting a station A, which may ybe at the central desk, with a for example, be what is termed in the` store service art, a clerks tube l preferably having mouth or terminal l at A,

A. `transmissionv a normally open lextends to the station B where the carriers may be delivered from a terminal 2 or known construction. vided with the usual valve 3, past whichpthe carriers emerge, and the current of air which passes in the direction ofthe arrow marke-d onV the tube l, passes laterally through the conduit l in the terminal 2, into the return tube 5. A. valve 6 vin this the insertion of patch from the station B `back to the station A. VSuch carriers aredelivered to the usual latter permits vof vcarriers theremto for des-k This terminal is prochute or shelf 7, pastv a valve 7 g the air cur- Y rent delivered laterally the exhaust tube 9 which delivers to a drum 10, or the equivalent thereof. l

In the present case the drum lOfis in direct through the tube 5 passing through theterminal casing 8 intoA nection 19 to the lead 20, will branches of the circuit communicationV withl a blower or pump 11, which exhausts the air from the-drum and which is driven byan electric motor 12, in lfnown fashion.

A rheosta-t 13, of preferably somewhat unusual construction,affords means to vary the eld resistance for the' of the motor, and will now be more ticularly described. It comprises a rheosta't arm 14, pivoted at 15 and carrying `a contact 16 adapted to be moved in-to engagement any one kofthe contact plates 17-17. resistance in the rheostat is, preferably with The formed of wire 18 coiled to` offer increasingly greater resistance between successive connections 19 thereto until a point 18', somewhat ab'ove its center, is reached, from either end thereof; the connections 19 leading to the Vrespectivecontact plates 17-17. A wire 19 connects the two extremities of the resistance 18 to a lead 20 which runs to a terminal. 21 of the motor field coils, while from the second terminal 22 extends a wire 23v which may conveniently be the negative lead to the sourcey of current. I prefer to provide a fixed resistance 19 in the connection 19 so that when in normal operation the motor n field will have at least such resistance in it.

lVhen the rheostat arm is in its lowermost position, the contact gagement with any of the plates 17 and no current will flow through the rheostat; but when said arm is moved upwardly, in the manner hereinafter described, until said contact 1'6 engages the lowermost plate 17', the field circuit is then completed but with a minimum of resistance in it to favor the starting of the motor. As the arm 14 thereafter moves up, an increasing amount of resistance will be cut into the field circuit; since while the initially very small fraction of the current which flows up through the resistance 18 and thence through the conbe slightly increased for each of the first few upward steps or successive engagements of the contact 16 with the plates 17, 4the current which flows through the wire i9 is at such times in any case almost'negligible, whereas the bulk of the current which had at first flowed from the lowermost plate 17 to the wire 20, while encountering practically no resistance other than the field coils, has a progressively and quite rapidly increasing' resistance introduced into its partial circuit or branch, as the arm 11i ascends.

jWhenthe plate 17 co tially to the point 18 tact 16, however, the resistance in the two leading to the wire 20 from this plate, will have become substantially equal if we except the auxiliary rresponding substan- Vor additional resistance 19 rovided in the wire'19. Continuous upward movement of requisite control paror otherwise made Y 16 will be out of en- 4 is reached by the conthe arm 14 after passing a point somewhat above the point 18', depending` on the amount of the resistance 19, on the whole tends to cut resistance out of the field circuit, so that when said arm reaches the position in which it is shown in full lines in Fig. 1, the connection between the corresponding` plate 17 and thewire 19 oers a minimum ot' resistanceand if it were not for the resistance19, practically all of the current would flow through this course. The resistance 19, however, provides the resistance in the circuit which it is desirable to retain therein at such time, and the motor will hence run as it normally should when a single carrier isl in through the line. Concerning the operation of the system when more than a single-'carrier isk in course of t 'ansit, this will be discussed hereinafter.

he armature connections may be made as follows: From the positive lead 2e current will enter the arm 14's or a conductive p0rtion thereof, and will pass therethrough to the contact 25 and after the arm in its initial upward movement has brought contact 16 into engagement with the plate 17, as above described, this contact 25 will be correspondingly engaged with the lowermost contact plate 26. Current will then flow from this plate through a resistance 27 to an extended contact plateY r28 from which eX- tends a wire 29 which in turn is connected to the armature of the motor; a fixed resistance 30 being preferably inserted in this wire.

The current emerging from the-armature passes via wire 31 to the negative lead 28, completing the armature circuit.

As the arm lt ascends, and during the time that the contact 16 remains in engagement with the plate 17, it successively engages the contact plates'26 and thereby progressively cuts out the resistance 27 of the armaturecircuit, so that by the time the contact 16 has by its upward movement com menced to vary the resistance in the field circuit, the armature circuit resistance will have become reduced to adetermined amount oiiered by the resistance 3() and the armature winding. ft willbe understood that during the normal operation of the system and until the controlling apparatus actually commences lto shut down the motor, the armature resistance will remain constant and the control of the motor will hence be entirely determinec` by ance in its field circuit.

The means for thus initially rheostat arm 14 to establish normal operating conditions in the system will now be described. rAssuming that Va carrier such as that designated 32 has been inserted at l for despatch to the station B;A such carrier will depress the lever 33 in a casing 34, to

actuating the course of transit varyingV the resist.

close a. preferably low voltage circuit across contacts 35. -This completes the following circuit: Current flows from, :torexamplda battery 36 through a wire 37 to air/arcuate contact 38, andy since at such time the arm 14 will be in its lower position, 'said current will traverse a bridging contact 39 to a second contact 40, whichwhile also preferably arcuate, may be shorter than the Contact 38. It then l'owsthrough the wire 41 to a wire 42 and from thence through the contacts 35 and their bridge 43, which is carried by the armor lever 33, to a Wire 44, whence the current passes to a wire 45 and through a starting solenoid or-magnet 46 to a wire 47 which leads back to the battery;

This energization of the solenoid magnet 46 draws up a bridge 48 to complete a circuit through the spring contacts 48, as follows: Current vfrom the main positive lead 24 passes up through a shortvconnection 49 and throughv the contacts 48--48 to a wire 50, thence through the main solenoid 51 to a wire 52 which is connected to the negative lead 23; a resistance 52 being preferably provided in the connection 52, to protect the solenoid 51. Thus, the instant that the magnet 46 is energized, the solenoid 51 will be correspondingly energized and its core 51 will be drawn up to thereby elevate-a plate or table 53 mounted upon its upper extremity, and the virst upward movement of this table causes it to pressa roller 54 whichv ismounted upon the extremity oit a conductive spring 55 carried by the arm 14, upwardly until said springis broughtv into engagement with a contact pin 56, which may project through the arm 14; this clo-` sure ofcontact between the spring 55 and the pin 56l completing thectollowing circuit:

' Current i-lows from thefbattery 36 through the wire 37 and contact 38 tothe contact 39 and from this latter through a connection 5? tothe contactipin V56. The current passes thence through the spring 55 to a connection `58 which extends to a `contact finger 59,

which at such time is in engagement with an arcuate contact strip or blade 60. The

fem-rent then passes through a wire 61 tothe wire 45, through a portion of which it flows to the starting magnet 46, whence'it passes through the wire 47 back to the battery.

1t will be understood from the foregoing that when the arm 14 is in its lowerniost,po sition its roller 54 will be held away therefrom by the action of the spring 55, since while the roller may evenbe in engagement with the table 53, as shown, the downward movement of the arm 14 is limited by a stop 62, to permitiol interruption of contactlbetween'said spring 55 and pin 56; but that as soon as and in 'fact the very instant that the solenoid 51 is even momentarily ener-l initial upward movement of Vthe solenoid core 51 atoncecloses a maintaining circuit for the primary solenoid or magnet 46. This `insures an upward movement of the lcore51 through a determined distance and the length ci: eitherorboth roi the contacts 38 and 60 determines the extent ot' this upward movement; since by the timevthat the core 51 ol the latter te at once drop Aclear l of the roller 54.

The spring 55 will aid the weight of the roller in separating said spring trom its pin f 56 at such time, so that before circuit can again be completed through the contacts 39 and 59, pin 56 will have been separated from spring and the primary solenoid will therea'lfter ren'iain denergiaed until; condi tions hereinafter referred to Aare established.

`lt will be observed that owing to the fact that the contact 40 is `preferably made shorter than the Contact 38, the finger 39 may remain in engagement with contact 38 after ithas ceased to bridge the contacts 38 and 40 with the `result that whilethe maintaining circuit continues to be inaiiiitained until contact 39 vis drawn out oi engagement with Contact 38, the wire 4,1, for example,

may be energized by tlie despatch of successive carriers "from, i'or example, station A, only during the short time that contact 39 is thus able to bridge contacts 38 and 40; but that after it has been freed from the contact 40, and until contact is restablished again at this point, the insertion oi carriers into the line will not cause current to iiow through the wires 41 and 45, and such insertion of carriers therefore has no direct effect upon the primary magnet, which tea- Vture is believed to be distinctively new Incidentally, it may be here observed, that V one advantage in this resides in the fact that after the maintaining ycircuit has been broken by theI disengagement of, for eX- ample, cont-.acts 138 and 39, such maintaining circuit cannot iji'orinally; be restablished under any circumstances until'contact finger 39y has moved back into engagement with contact 40 and he ce while the system is be ing controlled by the carriers themselves during their passage through the line, nor- 'l inally no current can be uselessly expended l.

in energizing selenoids 46. and 51, as a result of the introductiono successive carriers into the line. 1

Let us now consider theeii'ect on the system of the starting of the motor by the upward movement of the solenoid core 5l in themanner aboveV described. The held circuit is first made with substantially no resistance in it'other thanthat of the iield' itself, and immediately after-this the armature circuit is completed with i'ull resistamfe therein. The-inthe armature circuit resistance is cut out more orless gradually and f raoidlv as the motor will. ierinit. after which resistance is increasingly ii'itroduced into the lield circuit to speed up the motor. This resistance is cut in just as rapidly as is concomitant with safety' and asa result the motor is rapidly specded up until it is running at a rate materially in excess of what 'mitting flow oi vair is accelerated by this action oi' the motor.

The exhaust pipe 9 has extending therelroin apipe G3 in whichV preferably is located a valve 64;, and the pipe G3` opens at its outer extremity into the upper end ot' a cylinder '65 in which rides a piston G6. This latter may be of any suitable description and so will not here be more particularly considered, except that it should be stated that it is preferably provided with some such means as a leather cup 6G', for substantially preventingany flow of air around the piston, especially upon its downward stroke. The lower end oi the cylinder is closed by a head 67 through which extends a passage 68 which may be closed to any desired extent by needle valve 69, or' the lile,to permit of the desired seepage of air into or out of the space beneath the piston., as the case may be. There is also provided in this head a second ypassage 70 the opening of which. into said space below the piston, is provided with a check valve 7l, which in the exemplified construction merely a Ysmall leather flap. The passage 70 is con-4 nected by a pipe 72 to small casting or 'l' Y 73 in which is a normally open vent 74.

There is also provided a small cock or valve 75- ;For admitting ,a determined seepage of air into the pipe 72fwhen the vent 74 is closed by ay valve 7 6 mounted `upon the upper end of the stem ot thecore of magnet 46.

In this connection it will be observed that the spring contacts 48, although they are preferably engaged by their bridge 48 bemit of Thi s.

This morod 77 which extends through the head 67 and has pivotally connected' thereto at 7 8 a link 79 which in turn is pivotally connected to the arm 14; the connection at 7 8 between this linlr andV rod heilig adjustable to persetting the arm lll properly with respect to the Contact plate 17 when the piston is in its lowerinost position; a set screw 7 8 being` set into the rod 77 when the proper adjustment has been attained.

During the upward movement of the arm 14- through the action of the solenoid 5l, the vent 7 4; will be closed and the upward movement of the piston 66 by the thrust exerted L against its rod through the link 79,'will be retarded by the formation of a partial vacuum below the piston. By 'a proper adjustment ot the needle valve 69 and cock 7 piston G6 may therefore be caused to ascend at the rate desired, this rate ot course beingv as rapid as is consistent with the preventing or burning' out of the motor Vvby a too rapid change ot resistance in either its armature or field circuits; but for motors of relatively small size such as are used in connection with pneumatic despatchtube systems installed in stores and the like, the time required for the ascent of the arm 14 from its lowerinost position to the point where its solenoid core 5l drops downwardly therefrom as a result of the interruption of the maintaining circuit, which preferably, by the way, oc-

curs shortly after the maximum resistancev `18 has been cut into the eldcircuit, will be but a very few seconds. It is usually suflicient. to permit ofthis interruption of the maintaining circuit when the arm lel reaches its position lllV or thereabouts, since by such timethe mot-or should have speeded up to establish a suiiicient difference in pressure upon the opposite sides of the piston, to insure the continued operation of the system until the last carrier shall have emerged theretrom in the manner hereinafter described.

lifter the arm l-lhas ceased to be sustained by the table 53, there will be a tendency for the arm and its associated parts to move downwardly toward their lowermost positions, but such movement is in any case retarded so thatl it mustV consume at least several seconds, owing to the fact that air will be trapped below the piston 66 since the check valve 7l will at `once close under such circumstances and no air can hence escape through the pipe 72, despite the vfact that the vent 74 will at such time be open. The trapped air can, however, slowly escape past the needle valve 69 and the adjustment of this valve will determine the speed of descent of the piston.v Ii'no carrier whatsoever be present in the line, this downward movement of thev piston and arm 1a will continue and the motor will gradually .be shut down;` but if any carrier be present in the line 'a suiiicient load ivill be imposed upon the air current to create av sufficient rarecation of the air in the space above the piston to enable the air at atmospheric pressure therebelow toV maintain suchpiston in positionto hold the arm 14 substantially Where it is shown in full Y linesin Fig. 1. Obviously, lvvhen a lcarrier is descending through a long drop in, Vfor example, 'a vacuum line, there is a tendency Jfor-the vacuum ahead of the carrier to be brokenat such time and if the drop be 4of suflicient extent, the air in the tube in vadvance. of such; carrier may veven attain the pressure of the outer air or even indeed may in some cases be slightly compressed. Under such circumstances, the piston 66 Will `gradually descend but as it does soit will first cause vresistance to be cut progressively into the field circuit to speed up'the motor, which Will again rarefy the air in advance of the carrier vvith the result that the mo ment the carrier has passed around the-'bend at the bottom of this drop', ii' therel be such l a. bend in the line, Vsaid carriery nee-d not even momentarily comete rest in the tube,

as, for example, in theposition in which it is shown inthe tube 5, butrvvill be continued on its Way' toward its destination; here again effecting a savingv of time, Y

` de to eounf Now if no provision were ma y teracty the eii'ect on the piston of this speedslotted, asiat 83 and 84: to permit of the` ing up `of the motor, and since the load oi the carrier onkthe current of air is a relatively small one, there would be a tendency, once themotor had thus been speeded up, to thereafter maintain the piston in its n'iotor-operating position, regardless ot whetherithere Vvvere a carrier inthe line or not. A number of means can be employed AtOcOunteract this tendency, but the one which I prefery topuse has been selected for this purpose because it peculiarly Well adapts itself `to counteract the'motor atany one yof the` varying speeds 'of the latter which maybeV determined by the position of the arm 14: When the latter is controlling vthe motor through the resistance 18.

At 4the .extremity of the arm legislocateda roller which isadapted-lfor engagement `With a cam-acting operating arm 81 mounted on the stem 82 of. theqvalvev 82;

the latter beingshown'in detail in Figs. 2 and 3. "This valve may be in the Vform o'l a hollow cylinder, the walls of Which are passageofair lin through a cock or valve 85 Vfin amounts proportionate to the displace-L ment oflthe operatingarm 81 from the normal position in `which itis shown in full lines in Fig. 1, toward its extreme outer or l valve opening position indicatedin dash and dotted lines in said figure at 81. Y

The'air thus flowing through the valve 8:2

passes through a pipe 86 to the T 87 which connects the respective portions of the piper` 63 aforesaid, and the caml on the arm 81 is so shaped as to causel the valve82 to be cracked progressively moreand more openy as the arm' 14E moves up from the position in which, vor shortly after which, it-be gins to cut resistance kinto the iield circuit, Y

until said arm reaches the position lll aforesaid,.- rlh'enj as the arm moves farther up to progressively cut resistance out oi the `field circuit, the valve 8:2 is correspondingly closed to theend that if no carrier be in. courseoi transitl through the line, asuili-v lcient;amount of air may pass the vvalve 82 to counteract the effect which would other# `wise be exerted upon Athe piston 66 as aresult ofthe speeding up of the motor at substantially a rate. yin excess of its normal operating1 speed which would be determined by the positioningy of the arm 1li Where it is shown in iull lines in Fig. 1.

VlWhile the opening oi the valve82 in varyino' amountsmaythus he depended upon to `counteractthe speeding up 'of the motor,

When no carrier` is in the line.lit 'cannot counteractthe effect of theload of a carf rier on Vthe air current ii such vcin-rier is pr sent in the line; and indeed when the motor is speeded beyond normal, if there a carrier in the Vline atsuch time there willbe such a marked increase in the change oi' pressure in the air ahead of the carrier` askto quite promptly cause the piston 66 toascend to its normal operating position.

I shall now describe a feature vvhichr I regard `as of .considerable Vimportance fand one which is o'very general application to pneumatic despatch tube systems Where a pressure responsive device is employed as means i'or controlling the speed of the motor; so that I distinctly desire it to bev understood that the-construction novv to be described or any lequivalent thereof, is not to it together with its frame, Would, if unattached to the rod 77,.normally bey sustained the liquid, in equilibrium. The liquid i'i o Vthat the arm la reaches its may be retained in anannular receptacle 92,`

as frictionlessly as possible. The float is also preferabhT so proportioned to its container and to the amount and veight of the liquid Y inthe latter, as to cause the float Vto'reach the point in its downward lpath where it will be fully immersed at or about the time position lei. lWhen the float is thus pressed down into the `liquid and said arm' is in said position i thereof, there is a tendenoyv foi-*the float to Y raise the `piston and arm but as the varm apand this iirsertion, for example, of but yreadv in course of transit the preaches the position in which it is shown in full lines in the rigure, this tendency de! creases until, if the piston, arm 14s, etc., were without Weight, there would be notendencyV Y for .the float to move such parts farther upwardly.

'When the piston is moved farther upf Wardly from this point, as a result of the presence of, for example, two carriers in the line, there is additional weight thrown onto thepiston stem7 owing` to the faot that the float is now Vbeing` pulled up out of the liquid by amounts proportionate to thisr upward movement of the piston. Said upward "movement of the -armlil from its normal,

and as We may term it, singlerarrier position results in bringing the contact i6 suecessively into engagement with the plates l? at the upper end of theseries oi? these plates. progressively cutsV additionalV amounts of a resistance 94 into the eld circuit ot' the motor, with the result that the vlatter is again sneeded up, this time iu correspondence with changes in pressure inthe line normally occasioned bv the presence oi' two or more carriers sunniteneousl;r in

.Y course of transittherethrough.

This variable Weightv` or` the equivalent thereof, Whiehmav be imposed upon :the piston, it may be 'here noted', constitutes another meaus'for eounteraotin ggfV what l may term cumulative interaction between the means for establishing the air current and the governingV or controlling; device therefor, which acts responsivelv to variations in pressure in the s vstem. In other Words, were it not for the provision of some means for increasingly opoosin',g` the upward movement oi the arm 14- by .its niston in response to the a sinajle'addicarrier is aly un'vvardimovement of the piston .resultina' from Vthis additional load on theair current Wouldcut resistance into the ield to speed up the mo*- tional carrier. when a'iirst tional load on the line Y means in question and in Fifi'. 4; I have illusload, and if desired t into the field circuit, etc., until as a result of perhaps but the introduction ot only one additional carrier the piston `66 would be caused to move to the upper Vlimity 'of its travel and .the motor would be driven at a speed veryfmuch greater than is necessary for the transmission of but tivo carriers in the line.V Y v Y Y Y Y The fact', however, that soon as the ad- .Y ditional loan on theline Vcauses anupivard moi/'ement or' tie piston 66 and arm le, an additional weight` or other means for eeuuteracting' to, a limited measure the Veleot oit-the resultant speeding` un oi the motor. is imposed or caused to -act upon the pis ton-cheeks this Aprogressively7 cumulative action and onlv permits the piston to move up ja small part of its remaining travehjust sui'iicieut to eut infenoug'h resistance in the motor 'field to takercare oi If a third cari be introduced, While the other ttvo are still in course oi? transit, there will be a still 'farther upward "lum/'ementV of the piston and arm Withthis variable additional load; but not in excess or" the service requirements.

As above intimated l am aware of a number of equivalents for, the counteraeting trated a modification which instead of using;

e a float susnended from the' frame 88.em'-

plof/s weights which mayv be of' anyv suitable descriptionq but which l prefer to provide in the form of balls 95h95', which may be strung on wires oir-.cords 96, which are'atta ched to theframe 88. 'if he casing' or Loontainer97 `'which receivesfand supports these `weights as they re unloaded 1Lhereinto by the downward'movement et the vtrame 88', muv be'sunported 'from thecvlinder 65h57 a cylindrical inclosuro 98. llihen the piston rod or stem?? in its lowermost position, all oi: the balls 95495 may he in ei'iectfunloaded intov thev casing` 9T which Willv then support said balls or. Weights, butas the rod ascends. it nicks un f 1 Y load may be varied, -o'f the Chill? th at.. for exe-,i sbl e f,

down the motor tonormal operationthereof the small addij l-t in correspondence,`

ilo

iis

ually increasing' ills, as at9so Y Lofn'uive the :ii-inviato Y position 142 the piston may havesustainedlz i to this point but the load of the smalliballs' i V95, and farther upward movement to speed zol i-,Bsases for Y'the transmission of one carrier or for ad* ditional subsequentv speeding up of the motor following vadditional carrier insertions, the piston will ,then be loaded with successive balls 95.

' fhe speed counteracting means which i comprises the valve 82 and its operating cam may also be regarded as toY some extent an cquivalentA Vmeans fori` the cnuntera-cting n'ieans just described; but as l have shown how the camuied control. of a vent may be caused to counteract the effect of changing the speed of a motor in connection with one part of the-apparatus, it 'would needlessly7 binden the description'of the invention to particularize concerning all ofthe various kequivalents which may be used in lieu of the variable load devices, more especially described in thisconnection. lt will be understood, too, that devices which are indeed "gen-V erally considered as equivalents to weights are also vveryclearly.within the purview of this phase of my invention.

rl`he employment of either a float or a chain-like weight, affords an exceedingly simple construction which. is admirably adapted to compensate for ypredetermined changes in pressure conditions in thevsystem, the effectief which it is desired to counteract; while in so far as the travel ofthe arm 14 in connectionwith the resistanceV 18 is concerned, the venting valve which is first Acarnined open as resistance is Yeut in and valve'SQ, may bereducedto a minimum and that this wastage of air normally only oecurs ywhen but a single carrier is in course of transit and certain conditions arise in the` system which require a Vmomentary speeding up' of the motor, i valve SQ during a very short period following the emergence of the last carrier in the `line when the motor is correspondingly speeded up. At other times, when a single carrier is in course oftransit with the motor operating at normal speed fromA this condition, or when the motor is speededup as the result ofthe presence of two or more carriers in the line, there is not even this slight seepage of air through vthe pipe 86. It is for this i reason that the vupper end of the arm 581, ad-

jacent its pivotal'point is made arcuate about the point l5' as a center rather than to have cammed in thispart of the arm` again to or a further action of theA force the valve 82 open in correspondence j with the cutting in of the resistance 94: since uhile this might readily-be done it would involve a more or less constant waste of air,

'even though this waste be small, during the normal operation of the system foi-one or more carriers, andy further, lthe adi'antages resulting from the useojf the float. or thev like ("7 i y I. l wouldnbe lost. l l 'Y The inward movement ofthel arm 8l by its springllOOis limited by a stop 99, and the shape and site of theslot S3 in the'valve S2 vmay obviously bel variedfasdesired to enable the counteraction of the variations in 'speed of the inotorgwhen controlled by theresist-` anceflS, to a nicety, f Y

lt will be understood that the weight Vof the piston, its stein, the link 79 and the arm 14, will collectively be just sufficient to force the. float downto the bottom'most position thereof-in correarm 14;; and that while after the floatitself has been completelyimmersed there is but ditional thrust upwardly against' the pistoni;

nevertheless the arms of the 4frame 88 may be` so proportioned as ofV themselves toV exert a slightly increasing upward-f thrusty resulting from their immersion into Y'the lioluidy andthe consequentV upward displacement of a small but variable amount of the latter, depending the float and its frame,y

'i little further tendency forit to cause yan adupon the extent of immersion of said arms in said liquid. QAs a: result ofthe nearly balanced conditionattained by this upward thrust exerted through fthe arms of the frame 88 when the pistonis` in its lowerinost position', the solenoid 51' need'not bef a. strongy one; sincey when itsk core commences to move upwardly thereinto, itencounters but slight resistance, andpwhile this resistance .at first slowly 1ncreases, and thereafters'omewhat more rapidly increases until the ltable 53 hasv been lifted to the position from which it will drop free of the roller V54, .the solenoid in the meantimejhas substantially correspondingly increased its ability tol pull up its core, as 'the latter moves fartherand farther into the coil; so that even in this respect there is a certain coactionbetween the float and the operating solenoid.

Further, the operating or main solenoid 51 does nothaveto lift the arm le; very far before the motor has been speeded to maxi'y inuni'and thereafter the system itself sustains the arm, air 'being freely admitted through pipe 7 2 as required, while the solenoid core drops away not to Vgo into vservice* again untilthe motor has slowed down following the emergence of the last carrier,fto a point where contactBQ bridges vcontaotsl and fl() and onlythen or thereafter when a `carrier `is vrinserted for despatch through the line.

iio

85 spondence with the lowermost position ofthe .1 v

The provision of yielding springs for the contacts e8 also affords a maintenance of the ,circuit which energizes solenoid 5l, for a traction of a second vafter solenoid li6 is denergized; which permits the contacts to clear contacts l88 and 60,'01V one at least ofthem, by a safe margin to .insureV against ovei a remote possibility of a main-f ,tenante of e" ment of this circuit at 38-7-39--59-(50, by a cuit at andi'eestablislitoo Vepuickyfall ofthe'arm 14 after the tablev starts to drop. fis any descent of arm le is relatively' slow and astlie table V58 drops fre ly, the slight maintenance of contact at n35-i8 insuresthe denergization of solenoir. s eiland 5l as soon as the arm 14 reaches Y Vits positionV 14e. 'f

The primaryA Aor starting solenoid or niagnet t6 is not only controlled froinstation A when the apparatus is idle or substantially idle; but said magnet is also controlled in a similarfashion from station Bysincethe `tube 5 is also provided with a casing 34, having contacts therein, similar to that shownA in detail in connection `with station'A, and

these contacts'are respectively connected Vto the `Wires al and by-Wires 42 and 41H In General it'niav be stated that not onlv Y 2*.' w Y does the float 89 possess advantages `over merc Weights such as are shoivn in Fig.- 4, or the equivalent thereof, for reasons above indicated; but fuither by its veryV nature as float in a body of liquidVit tends tosteady the action of the apparatus and not to permit mere'inomentary fluctuations in pressure tvo-'materially Vdisturb the adjustment of the arm la. Also the valve 64e by its presence in the connection leadingto the pressure sensitive apparatus, acts to throttleV down moinentary pulsations so that these latterV have to persist for an appreciable period of time, ,vfliicl'i of course is short but not merely mo- Y inentary, before the piston and its associated parts can have the positions thereof materially changed. y y

`The operation of the system, in. general,

will now be considered.

f'issuming that aA carrier to be despatched either from station A to station B or vice versa, the-closure of contacts in the casing gaat the station from which the carrier is despatched effectsan energization of the starting magnet i6 which promptly rises to close the vent 74- and complete the circuit ,Y motor has `been fairly started.

vacuum below the piston 66 and the setting of the valves 694 and determining the speed of movement of the arm.

The motor is startedby having its field circuit completed and then its armature circuit, which is completed immediately thereafter, has resistance out out of it until the Resistance is then cut into the field circuit until the motor has been speeded up beyond noimalrequirements for the transmission of the single carrier thus far inserted.

About the time that it has thus attained its maximum speed, so V*that the building up of the carrier transmitting How of air through the tubes has been accelerated, and

the carrier started on its Way,'the maintain-V ing circuit is broken by the :separation of Vcontact39Y from contact 38 and of contact 59 from contact. 60, which results in the denergization ofthe magnet 46, followed by the de'o'nergization a fraction of a second later of the solenoid 51, Which-permits the table 53 to drop, breaking the maintaining circuit. f ihedroppiiig of the valve 7 6 upon the deenergization of its magnet, at once admits :tirait atmospheric pressure through the pipe 72,V so that if anything, there is a countervacting tendency for the piston 66 to move upwardly rather than downwardly at this time. Said piston thereafter, by reason of the presence of the load on the air current Y in the line, continues tomove up until it has cut resistance out ofthe field to a sucient extent to cause the motor tov operate at a speed lvvhich is above that required for the normal transmission of a singlecarrier.

Duri the time that the arm 11i-'Was Vthus moving upivardlyivith its contact V16 suceessively in ,engageinent with the plates 17, at first by the upward thrust 53 and latterly by the upward pull upon the of the table 4 rod 77, the valve S2 was at first gradually opened' to permit of the requisite introduction of air to balance the increase in speed of the motor, and thereafterwas correspondingly closed as the speed of the motor den creased. llien normal speed is attained, the valve 82 is entirely closed and preferably remains closed during any farther upward Amovement of the arm la resulting. from thev imposition of additional loads on the carrier transmitting ioiv of air.

During theascent of the arm la toward its normal single-carrier-operating position,` the float aided and favored vthis upward movement but toa Vless and less extent as the noi'- nial position of ther arm ivas'approached. iihen an additional carrier yis inserted at either station, the consequent increase in load en thel air current raises the piston 66 and its attached float yand Vrheostat arm; vbut as this movement occurs the lioat is lifted above its normal single-carrier-transinitting position, and this additional loadupon the pis- 'a result., the.ymotor speeds` up only,to an amountsufticient to take Careof the additionalload imposedon the line. `Eachl successive Carrier thus -1ntroduced=when carriers. preceding it are stillL in .course` .,of

transit or when a icarrierfor carriers are in course of transit through lthe other `tube, correspondingly affects the setting of the controlling device and the motor is speeded up by'j ust the amount required.

As each successive carrier is introduced there is no renergization of the primary or startingmagnet so long as the rheostatarm 14 hasnot moved down to a position'wher'e it is nearly ready to stop the motor; but rather the control'of the motor is 'through the `variations in pressure in the system resulting from the imposition of loads thereon.

When a carrier .drops `dowgnthrougha considerable distance to more or less comf press the air ahead ofit, the pressure inthe air'above the piston rises and the piston falls, its Vdownward fall'A being retardedzby the air trapped in below it, whichcan only escape past theneedlevalve Y69. At such time as the arm 14 descends the motor speeds up `and hence tends to again rarefy the air in advance of the carrier, to speed it on its way, while this speeding up ot the motor is compensated for in so far as thepressure sensitive mechanism is concerned byy the cracking of the valve 82. yAs soon as the load of the carrier is` again feltupon the air current, which owing to this speeding up of the motor is almost at once, the piston 66 tends to move up again to restore the arm 14 to its' normal single-carriertransmitting position. The descent of the piston 66'occasioned by this drop of the carrier through a considerable distance in the line, is also increasingly opposed by the float as the latter is immersed more and more deeply into its bath. As the connection betweenwhat in the present case is an exhaust pipe and the` pressure sensitive apparatus, is throttled down by the valve 64, theladmission ot air through the valve 82 need be but small indeed, being correspondingly throttled down by the cock or valve 85.

Assuming that several carriers` are in course of transmission at the same time and that the arm 14 istat almost the upper end of its pathl of travel, with most or all of the resistance 94 cut into the field circuit and the motor correspondingly speeds-d upf-,as

ka carrier emerges, to reduce the load on the line, there is a corresponding downward movement of the arm14 tb shut down thel speed of the motor. Obviously, when such a carrier passes the valve 7 A there will be a momentary. inrush of air at atmospheric pressurentd theipipe ;v but als) the .Gunners tion-between-- said..pipe and the lpressure sensitivel apparatus is throttled down by meansof ythe valvel64,this pulsationv cannotrin anycase greatly ,altect the disposition of the piston66, especially since any abrupt downward movement of this latter is opposed by the air, trapped therebeneath and float and the liquid by the 4,inertia ot the whichitmust displace when it moves downwardly, thereinto. When all of the; carriers in coursei of 'transmission have emerged from the line,

before ;the system becomes idle, its motor will first be speeded up fora short time and thereafter if no Ycarrier be inserted in the interim, the resistance will be cut out ,of its eld circuit and resistance will then be cut intoits armature circuit to the end that it thesystem is arranged, as itpreterably is, andas shown, to completely stop said motor, this end maybe attained by the movement of the ,arm 14 to its lowermostposition.

, The herein described system is hence adapted to operate with substantial certainty, it beingv 4practically impossible in lines of even considerable length, to stall a carrier in the line, while( if a carrier be heavily laden so thatits trictional engagement with the tube' is relatively great, not only will the apparatus continue in opera-y tionl so long as this carrier is in the line at all; but further the very tact that the carrier isy heavily laden, as forA example if it be filled with coin or the'like, will cause the motor to speed `up to a sufficient extent to cause said'.` carrier normally to travel toward its destination at a speed considerably in excess of that-which wouldy be imparted to it it the motor were not thus controlled, and yet by reason of the provision of the float or some one of the equivalents thereof, of which I am aware of many, thisincreased load on the line does not cause the motor to race in excessof the service requirements.

Having vthus described my invention lwhat I claim is:

1. A pneumatic despatch tube system comprising a line of transmission tubing, means to establish a flow of air through said line to propel a carrier, said flow tending to increase at the instant that it is unburdened of all carriers, and controlling vmechanism comprising' means, controlled by this change in the air current, tor iirst causing a still turcrease at the instant that it is unburdened of all carriers, and controlling mechanism comprising means, controlled by `this change in the air current, for first causing a still further increase in the How of air through the line normally effective to propel any carrier which would otherwise tend to remain in the line and co-acting means to disestablish the carrier propelling current of air when no carrier is in the line to resist said further increased ow, said mechanism having pressure-responsive provisions to restore the normal flow of air through the line in place of disestablishing said air current when a carrier still is in the line.

3. A pneumatic despatch tube system comprisinga line of transmission tubing, means to establish a flow of air through said line to propel a carrier, said flow tending to increase at the instant that it is unburdened of all carriers, and controllin mechanism comprising means, controlle by this changein the air current, for first causing a still iurther increase in the flow of air through the line normally effective to propel any carrier which would otherwise tend to remain in the line and co-acting means t0 disestablish the carrier propelling` current of air when no carrier is in the line to resist said further increased flow, said mechanism having pressure-responsive provisions to also increase the air flow rst mentioned, when a second carrier is inserted for transmission while the first is still in the line.

4e. A pneumatic despatch tube system comprising a line of transmission tubing, means to establish a iow of air through said line to propel a carrier, said flow tending to increase at the instant that it is unburdened of all carriers, and controlling mechanism comprising means, controlled by this change in the air current, for iirst causing a still further increase in the low of air through the line normally effective to propel any carrier which would otherwise tend to re main in the line and co-acting means to disestablish the carrier propelling current of air when no car `ier is in the line to resist said further increased flow, said mechanism having pressure-counteracting provisions to permit its said co-acting means to become effective in spite of said further increased flow so long as the latter is unresisted.

l 5. A pneumatic despatch tube system comprising a transmission tube, mechanism to establish a carrier propelling current of air through said tube, and means to control said mechanism by a change in pressure in a part of said system,saidk controlling means having provisions for itseli'l effecting a change in pressure in said part by its action on said mechanism, and a venting device operated by said controlling means to counteractthe eifect* on the latter of said last mentioned change, to maintain said controlling means responsive to changes in pressure in said part unoccasioned by its own action.

6. A pneumatic despatch tube system comprising a line of transmission tubing, an electric motor and pump for creating a carrier transmitting flow of air through said line, an electric circuit for operating said motor, a rheostat in said circuit for controlling the operation of said motor and pump, a pressure controlled device connected to said line and having an element thereof movable by differences in pressure upon different sides of said element, operative connections between said rheostat and said element whereby the rheostat is adjusted to speed up the motor and pump as the load of an additional carrier is imposed upon the air current traversing said line when said current is already propelling a rst carrier, said' imposition of said additional carrier upon the air current in said line causing an increase in the difference in pressures upon said different sides of said element, and means to impose a load on said element to in part only oppose the eect of said increased Mdiierence in. pressures as said element responds to said increase.

7. A pneumatic despatch tube system comprising a line of transmission tubing, an electric motor and pump for creating a carrier transmitting liow of air through said line, an electric circuit for operating said motor, a rheostat in said circuit for controlling the opera-tion of said motor and pump, a pressure controlled device connected to said line and having an element thereof movable by differences in pressure upon different sides of said element, operative connections between said rheostat and said. element whereby the rheostat is adjusted to speed up the motor and pump as the load of an additional carrier is imposed upon the air current traversing said line when said current is already propelling a first carrier, said i1npo sition of said additional carrier upon the air current in said line causing an increase in the difference in pressures upon said different sides of said element, and means to counteract the retroactive effect on said element of the speeding up of said motor and pump.

8. Apneumatic despatch tube system comprising a line of transmission tubing, means for establishing a carrier propelling flow ot air through said line, a pressure controlled device connected to said line and having an element thereof movable by differences in pressure upon different sides of said element, operative connections between said element and said means to control the latter by a movement of the former, and mea-ns to impose a load on said element to in part only oppose the effect of an increased difverence in said pressures which tends to move said element in ay determined direction, said last mentioned means having pro- Vvisions to remove said load when said'element is oppositely actuated by a decrease in the difference oflsaid pressures.

9. A pneumatic despatch vtube system conipi'ising fa line of transmission tubing, means forestablishing a carrier propelling iow of air through said' line, a pressure controlled device connected'to said lineand having an elementfthereof movable by differences in ment, voperative connections. betweensaid pressure upon different sides of said eleelement and said means tot control the latter bya movement of the former, and means to impose la progressively increasing load on lsaid telement tooppose the eHect ofprogres- "sively `increasing .1 differences ni said .pressures whichtend to move said .element disproportionately fartherand-farther in a determined direction.

10. A pneumatic despatch i tube `system comprising a line of transmissionftubing, means Jfor establishing a carrierlpropelling flow of air through said line, a pressure coiitrolled device connected to .said vlineand having an element thereof movable by differences in pressure upon diiierent sides oi' c said element, operative connections between said element and said means to control the latter bypa movement of the former, a variably acting device, having aA tendency for movement into a determined position and a tendency to increasingly opposecontinued movement thereofout Aof saidposition, forl correspondingly opposing a movement of said element, land operative connections between said device and said element to enable said device to transmit its said tendencies to said element.

11. A. pneumatic despatch .tube system comprising. aline of transmission tubing,

Y means for establishing a carrier propelling flow of air through saidline, a pressure controlled devicer connected to said line and having anelement thereof movable by dit. erences in" pressure upon different sides oi said element, operative connections between said element and vsaid' meansto control the latter by a movement of the former, a varilably acting device having a tendency for Amovement into a determined position and .c increasingly opposing movement a thereof f out ofsaid position in either of ytwo direc-Y n tions, for opposingl corresponding movef ments of said element, and operative connections between said device and said element, lsaid device through the respective connections aforesaid, tending to holdy said means y in a normal operative position thereoii. Y 12. A pneumatic despatch tube system comprising a. transmission tube, a carrier to travel through said tube, means to establishwl xa rate of flow of air through said tube adequate to propel .said carrier, fand: coi-acting fifnechanismy to 4temporarily-1.*increase v said* :.fiow: toifairrbeyond- -thatvavhiehiwould nor-i. 'pressure;responsive-,means. torpre- .finally follow the removal of the loadof said "carrier from the air current, when said air current is unburdened of said carrier.

13. A pneumatic despatch tube system comprising a transmission tube, a pump for creating a flow of air through said tube, a motor `tor driving said pump, a rheostat to control the speed of said motor and .thereby of said pump, electrical connections 'for said rheostat and motor, al pressure-responsive device for controlling adjustments of said rheostat, connections betweenv said device "and said-transmissionA tube whereby, changes in pressure in the latter control the yformer,

yand a float having a bias for movement into a determined position thereof, opeiative connections between said float and a Ypart of said device, said float by its said bias tending to set said device and rheostat respectively in adjustments corresponding to said position and vvariations in pressure in said tube variably acting through said deviceto at'times resist said tendency and at other times to co-actf therewith, ac-

` cording to the nature of said variations.

iiormeiy'a float having a bias for movement into 1a. determined positionl thereof, operative coiinectionsbetween.said 'Iioat and a part of said device, said float by its said bias tending to set said device and rheostat respectively in-adjustments corresponding to said positionv and variations'in pressure in said tubel variably'-acting through said device to at times resist said tendency and at lother-times to co-actftherejwith according to the 4nature of said variations, and co-acting means` to initially adjust said rheostat to operate said-motor and vpump to create a carrier propelling -iiow of air `through-said. tube and-'thereby to render operative said device-and its float.

comprising; a transmission tube,f means to establish av flow of air through said-tube,y a

" device to control said means to vary said flow, pressure-responsive means to control said device, connections between said responsive means to control'sa-id -tube,said pressureresponsive means having part-movable ina determined path Onewayor the` other in accordance vwith variations I in' pressure in "said tube, andJmeans-f-'or. imposing a variable resistance tothe; motionl offsaid 15. A pneumatic despatch -tube system` vent cumulative pressure-changing inter-1 action of said device and flow-establishing means which would .unduly displace said part for a minor variation in pressure in said tube.

16. A pneumatic despatch tube system comprising a transmission tube, a pump for creating a How of air through said tube, a motor for driving said pump, a rheostat to control the speed of said motor and there by of said pump, electrical connections for said rheostat and motor, said rheostat having a controlling part and resistances to coact therewith to automatically lirst speed up said motor and thereby said pump just before the system is rendered idle for the transmission of carriers, and co-acting means to thereafter maintain said system operative for the transmission of a carrier it' said carrier be present in said tube when said pump is so speeded up.

17. A pneumatic despatch tube system comprising a transmission tube, a pump for creating a How of air through said tube, a motor for driving said pump, a rheostat to control the speed of said motor and thereby of said pump, electrical connections for said rheostat and motor, said rheostat having a controlling part and resistances to coact therewith to automatically irst speed up said motor and thereby said pump just before the system is rendered idle for the transmission of carriers, means to thereafter maintain said system operative for the transmission of a carrier if saidcarrier be present in said tube when said pump is so speeded up, and means to counteract the effect on said last mentioned means of the speeding up of said motor and pump, when-y -no carrier is in said tube.

18. A pneumatic despatch tube system comprising a transmission tube, a pump for creating a flow of air through said tube, a motor for driving` said pump, a rheostat to control the speed of said motor and thereby of said pump, electrical connections for said rheostat and motor, said rheostat having a controlling part and resistances to co-act therewith to automatically first speed up said motor and thereby said pump just before the system is rendered idle for the transmission of carriers, means to thereafter maintain said system operative Jfor the transmission of a carrier if said carrier be present in said tube when said pump is so speeded up, and provisions for varying the speed of said pump in accordance with service requirements resulting from a plurality of carriers being simultaneously in course of transit.

19. A pneumatic despatch tube system comprising a transmission tube, a pump` for creating a How of air through said tube, a motor for driving said pump, a rheostat to control the speed of said motor and thereby of said pump, electrical connections for said rheostat and motor, said rheostat having a controlling part and resistances to co-act therewith to permit of a reduction in speed of said motor when the system is to be rendered idle for the transmission oi' carriers, lin accordance with a determined movement of said controlling part, means to retard said movement, and means, controlled by the current of air created by said pump, for normally instituting said movement automatically after the emergence from said tube of the last carrier in course of transit therethrough, said last mentioned means having provisions to reverse said movement of said part if the latter has resulted from a fluctuation in pressure in said tube caused by a temporary unloading of they air current when the last carrier has not yet emerged from the tube. i

20. A pneumatic despatch tube system comprising a transmission tube, a pump for creating a flow of air through said tube, a motor forV driving said pump, a rheostat to control the speed of said motor and thereby of said pump, electrical connections for said rheostat and motor, said rheostat having a controlling part and resistances to co-act therewith to permit of a reduction in speed of said motor when the system is t0 be rendered idle for the transmission of carriers, in accordance with a determined movement ot' said controlling part, and means, controlled by the current of air created by said pump, for normally instituting said movement automatically after the emergence from said tube of the last carrier in course or" transit therethrough, said last mentioned means including` a timing instrumentality and also provisions to reverse said movement of said part if the latter has resulted from a fluctuation in pressure in said tube caused by a temporary unloading of the air current which persists for a time period of less duration than that provided by said timing instrumentality.

21. A pneumatic despatch tube system comprising a transmission tube, a carrier to travel through said tube, means to establish a rate of flow of air through said tube adequate to propel said carrier, and co-acting mechanism to temporarily increase said iow of air beyond that which would normally follow the removal oie the load of said carrier from the air current, when said air current is unburdened of said carrier, said mechanism including provisions for then gradually diminishing the flow of air through said tube after such temporary increase until said iow is completely disestablished 22. A pneumatic despatch tube system comprising a transmission tube, a carrier to travel through said tube, means to establish a rate of flow of air through said tube adequate to propel said carrier, and co-acting mechanism including means to retard al movement thereof, to first increaseand then curtail said rate of flow normally upon the emergence of said carrier, the duration of said increase being determined by said retarding means. l

23. A pneumatic despatch tube system having therein a transmission tube, a pump for creating a flow of air therein, a motor Jfor driving the pump, and means for varying the speed of the motor in response to the load on the moving current of air, said means comprising devices acting on decrease of load rst to increase the speed of the motor, then to decrease it, and then to stop it.

24. A pneumatic tube system having `therein a transmission tube, a pump for creating flow in the tube, a motor for drive ing the pump, and means for governing the speed of the motor controlled on variation in the pressure in the tube, said means comprising devices for automatically increasing the speed of the motor on decrease or load, and devices actuated by the governor for increasing the motor on reduction `of load, said devices acting to stop the motor after a predetermined duration of such reduction.

In testimony whereof I have affixed my signature, in the presence of two witnesses. i v CHARLES P. HIDDEN. Witnesses:

CHARLES O. LAURIN, RUTH E. FISKE.

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