US1774857A - Limit switch - Google Patents

Description

Sept. 2, 17930. A, TER VEHN l 1,774,857-

LIMIT SWITCH Filed Sept. 28, 1927 mi! ll Il Il ll 7////////////////// gru/vanto@ Paiemedseptyz, 1930 i 'y I 01,774,857 l' UNITED STATES v f i f ,ALBER'YEOTEa v'nnivyor 1 Y Application filed 'september 28, 1.927; ,Seala-N l The present invention'relates to pumps for 43 which carries a spring contact 44,.v said dispensing oil7 gasoline and similar liquids, spring' contacting continuously with themey and particularly to pumps of the above char# tallic disc 40, as may beV clearly seen from" Y acter which are electrically actuated and in Figs. 1. and 2. :On'the said insulated support which the measurement'of the' liquid toghe disy42, Vthere is mounted a Contact carrier 45 tov pensed is effected automatically. More spewhich is'fiXed aspring contactblade46 which y c cifically, the invention resides in the provision may-'bepressed againstthe surface of disc of an improved limit switch for automatically 40 Vby a button l47, 'saidzblade being heldin f controlling the current supply, such switch' its tensioned or compressed position by means 10 acting to' interrupt automatically,under pre:y of a' springcatch or detent'49 carried" by a Q61).` determined conditions,the circuit whereinthe brzi'cketz48 on-l the support 42. i Thedetentv motor that drives the pump is included; `49 is ,provided with aicut'awaypart'O aeri In the accompanying drawing: v Initting-it to pass overthe disc i38and t0 be- Figure 1 is a front'view'of the improved engaged contiguous'fto the 'said cut-away part v limitswitch; y bythestops39ffof discj38. M50-and 51 are Fig. 2 is a part-sectional side view thereof; the terminals correspondingto contacts "46 Figs. 3 and 4 are fragmental vperspective and: 44, respectively, andrt'o 'which' terminals views, in diiferent positions, yof the springs areconnected, the wires! fl-leadiiig from Y which constitutethe electric contacts. i a suitable sourceQof current'(not shown) v y In the construction'illustrated,9 indicates "Ilie apparatus furtherincludes a main 73' the operating shaft of the apparatus which switch-tof approved character for throwing is connectedfto be driven from an` electric the entire apparatus into ineffective condin'iotorlnotshown) of` any lappro'ved'design tion, for instance at night; and with the ar# and itself facts to drive the pump proper rangement shown and described, it is evident f (also unillustrated). y I that by acting on spring 46 by means 'of push- 75 To effect the starting and stoppingof the button 47, said spring, owing to itsresilience, motor, in order to actuate the pump and also will contact with conducting disc 40, thereby"v 5 to adjust its workA in accordance with pre-J closing` the motor circuit andv startingthe determined quantities of liquid, the following operation ofthe pump. n

parts or devices are provided: To'the shaft Rotation of vshaft A9,'as will be apparent, Si 9, 'there is secured a gear 36 which meshes in eects rotation of gem 37,2H1Cl the members a predetermined relation with another gear secured to it and,-consequently,` at a certain f 37 fixed to a shaft 41; the ratio being in this movement, vone of the stops 39vWll Strike vinstance 1:4, so that for each four complete against the lart 50 of the detent 49 (see y -stroles of thepump piston (which has a.l Fig. 3) and eX the latterrightward so that 8,5 f driving connection with shaft 9), the gear 37 it willv be released from engagement with the willmakeone complete revolution, Assum` free endv ofspring 46 which, due to its re- Y ing that at each effective stroke of the piston silience, will then rassume theposition shown the volume of liquid drawn in is equivalent in Fig.` 4, 'separated from conducting disc to 5 liters, for instance, one complete revo-1 40, thereby opening the circuit and causing '90 lution of gear 37 Ywill correspond with the the motor to stop.The stop 39,as the counter` f vdischarge of" 20 liters. Gear 37 yhas secured clockwise rotationof disc 38 continues, will e v v to it adisc 38 of insulating material, and ultimately pass by the part 50 of the detent at the centralpart of said disc there is se` to the other side thereof,cthis taking place cured a metallic conducting disc 40. Tle aboutV the same (crsubstantially the same) 9,5, insulating disc 38 carries a set of stops 39, time that said detent is disengaged from a spaced at convenient intervals apart, say 90", spring 46. The apparatus is ready for a and arranged radially.V y further operation when the Fig. 4 position `42 is avmember of insulating material and of the parts is assumed; the angular distance providing a support for the Contact member between the stops 39 governing the number of `revolutions, of shaft 9 and, accordingly, the

quantity of liquid discharged, since the latter is invariably the same for each stroke of the pump. e,

I claim:

1. A limit switch for an electric circuit, embodying -a driveninsulating disc, a conducting disc fixed thereto, a set of' coacting flexible contacts, one of which is adapted to engage the vconducting disc and thereby complete thek circuit, means for holding said contact in such engagement, and releasing means carried by therinsulating disc Vfor terminating said engagement automatically. i 2. A switch according to claim 1, in Which the vset of contactsjincludes a spring blade constantly engaging the conducting disc, and

ducting disc fixed thereto, a spring blade cona second blade normally spaced fromsaid con'- ductingdisc but adapted to be moved into contact therewith, and in which `the contact-hold ing means acts to hold the second blade incontacting position but is released by the releasing means on the insulating disc.

3. A limit switch forr an electric circuit, embodying y'a e driven insulating disc, a constantlylengaging'the lconducting` disc, a second blade normally spaced from said: conducting disc but adapted to be moved into contact therewith,a spring detent'acting to engage the second blade and hold itin contacting position, and aprojection on the insulating disc adapted to'A strike said detent and disengage it from the second blade. i 1

` Y.ALBERTO TER VEHN.

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