US2436448A

US2436448A - Automatic timer for toasters or other apparatus

Info

Publication number: US2436448A
Application number: US711544A
Authority: US
Inventors: Lester E Padelford
Original assignee: OILJAK Manufacturing CO Inc
Current assignee: OILJAK Manufacturing CO Inc
Priority date: 1946-11-22
Filing date: 1946-11-22
Publication date: 1948-02-24
Anticipated expiration: 1965-02-24

Description

Feb 1948. L, E. PADELFQRD k ,4 ,448

AUTOMATIC TIMER FOR TOASTERS OR OTHER APPARATUS Filed Nov. 22, 1946 AQ Z esferifzafifd INVENTOR AT ORNEY Patented Feb. 24, 1948 223365448 AUIQMAT5%2%%Q%IEBS e o he. 011' "Mgmclalhz gt '1') The-invention here disclosed relates totiming mechanism and-particularly-ior apparatus such as- -taster-s, involving heat or other variables.

Asa practical applicationthe invention 1 relatesto toasters o-f the-type disclosed in the Warner Patent No. 2,371,084 of March 6, 1945, in which the toasting time is divided up into two-periods, a first or initial period of predetermined duration andasecond period of=variab1e duration, depend: ent upon heatconditions in the apparatus at the time.

Particular objects of the invention are to pro vide a timer of simple, inexpensive and practical constructionwhich will operate on the principle outline, w th a pred m n first period and a, ve eb es cond or final period urt er objec s ar to re ide uch m chanism me ierm wh ch an e i adil s em n w th eek e eaeme it me a isms-9f more e le eenvem e l. r acce ted e i nihe d s ra i et an h neve feet-zine through which the purposes of the inventi are attained areset forth 0.1 will appear intheco irsc of the following specification.

Th aw n a c m a in and min a Of the spe ifi a ion llust a ap e ent {eommen cial embod ment of t e in en i St uctur however, ma e modified and changed as regards immedi te il strat on. a l within the nte t and b ead sco .e the ashe ienaf d fined and aime Fi 1 in the dra ng is a hre e rt se ienei V e o a eleek movemen ha i the i v ntion ncor orated t rein th s ew be akene th he it m p ate. of mo ment e oved and showin he Par ih dle e t en;

i a. i andv .ni re. fra men ary vie showing the trip lever lowered to s t art the timing train;

31s a detachedview of the variably set cam lever for determining the duration of the second heat period above referred to.

In the illustration, portions of ;a standard-time train are shown made up-of a trip iever--5=pivoted on acenter 6; tensionedpy a springl--- ar 1d-'carrying a spring pawl or dog Behgageahle wit-h the tooth -9of a cam segment liicol-ipled througha tnr n springclutch H with a mair -gear -izwindriving engagement with the escapement -train--indicated generally at l3.

In this particular embodiment, downwal d movement of lever 5, which may beefiectedhythelowering of the bread slide .of the toaster, from the Fig. =1to the Fig. 2 position, tensions thespringi and thus sets the escapexnent mechanism into operation. llpward" movement of this lever scone tinuesiuntiithe dost-is released; item h t th 9 of .s ement 10: whe upon the le er snare in? ward; in, thee-case of; the o dinany toaster. te-tr p the-latch h di The present inyg t n i :n eia i am-r cher teem-pains the has "8. w ich ii-7W6 exampl ver i9 i ivet ai ene nd at- .25 asteeterin v tei e. homin t th it nto engagem nt within? e hedii eemeni and tensioned' toward such segment by a spring 2 I A special feature of ft'hQ lockin g lever 19 is that on the edgetoward the segment it is formed with two carntracks 22-, '23, one in extension of the o'th er and engageable successivelyby a roller 24 onthetrip-lever.

These two-carntracksm ay be consideredas representing the two toasting intervals, the lower cam surface 2-2-representing 1 the first predetermined interval andthe upper track 261 representing or providingfor-the second variable time -inter-val.

The lower, fixed-period cam track 2 2 may be substantially concentric with the arc of travel of'the roller 24, since for this period it is only essential-that the locking toothlii be held out of engagement with-the segment H; This track terminates -in a definite high point 25 from which the upper track 23" fades outwardly relatively rapidly-- so as to-let-the holding tooth on this' leve-r come inwardly into engagement with the segment of the timing cam assoonafter the end of thefirstperiod, as maybe determined by timing cam.

During the preliminary fixed interval and ior actuated lever is represented at 26 in Fig. 1, engaged with a finger 21 on the upper end of the cam lever l4. As a consequence this lever, while free as in Fig. 2, will be positioned by the bimetal or like element, and this positioning locates the cam 15 in position to be engaged by the roller l6 and release the dog 8 at a certain timeinthe upward spring impelled travel of the trip lever 5, thus to efiect the uncoupling of this lever from the time train segment iii an elapsed time after the end of the first predetermined interval.

The operation will be clear from the foregoing.

The lever which is to release the latch holding the toaster in operation, or perform someother useful function, is spring tensioned by forcingit downward from the Fig. 1 to the Fig. 2 position. In such motion the shoulder 28 at the heel ofthe dog 8, encounters the back of the segment IE! to carry the same forwardly, this being permitted through the slip of the spring clutch ll without disturbing the escapement train. At the end of the downward movement of lever 5, with the dog 8 dropped in engagementwith the tooth 9, the lever will be coupled to the escapement and hence the power of the spring I, tensioned by the lever, be applied to the escapement train. I

In this downward movement of lever 5 for ten sioning the drive spring and coupling the lever tothe escapement, the roller 24 on the-lever encounters first the non-concentric cam surface 23 to start the spring loaded cam lever 19 swinging outwardly to clear the holding tooth l8 from segment l1, and then the more or less concentric cam 22 to hold the cam lever in such relation freed from the segment of the timing lever Hi. The latter, now freed of the locking lever I9, is shiftable by thermostatic or other means and therefore assumes a position as determined by such means. This position may vary in the time interval that the roller 24 is traveling over the fixed-interval cam 22 and beyond. that on over the variable time-interval cam 23, so that the device is sensitive to varying temperature changes. The roller 24, as it rides up the cam 23, allows the locking lever 19 to swing inwardly until a point is reached where the lockingtooth l8 engages a tooth in the segment l1 and thereupon secures the timing cam in the position to which it has been shifted by the thermostat, The dog 8 will then be tripped by engagement of the roll it with the cam l5, in accordance with that particular setting and securing of this timer cam. On such release of the dog the spring tensioned trip lever 5 is uncoupled from the drive segment H] at the head of the escapement train and hence is freed to be snapped upwardly by spring 1 into the position shown in Fig. 1.

In the released idle position of the parts shown in Fig. 1, the locking lever I9 holds the timing cam M in the position to which it was last set, but the bimetal of the thermostat ordinarily is sufficiently flexible to accommodate itself to this condition without injury to any of the parts and when unlocked as in Fig. 2, the bimetal may then assert itself to set the timingcam in proper position for the then existent temperature-conditions.

The parts required to make up the'invention are relatively few, of inexpensive construction and can be readily combined with escapement mechanisms-of approved design; While of particular importance for use with toasters, broilers and the like, it will be apparent that the invenfion may have many other uses and that the sfiting of the second variable time interval may 4 be either automatic. as described, or the device be set manually or otherwise.

What is claimed is:

1. A timer comprising an escapement, a spring tensioned lever for powering said escapement, means for coupling said lever to said escapement, a timing cam for effecting uncoupling of said lever from the escapement, said timing cam being shiftable into diiierent positions of timing adjustment, a spring tensioned locking lever, companion toothed detent elements on said locking lever and timing cam engageable in diiierent relations in the different positions of said timing cam; said locking lever and said spring tensioned lever having companion cam and roller elements engageable in the movement of said spring tensioned lever to effect release of said companion detent elements in one range of travel of said spring tensioned lever and to permit engagement of said companion detent elements in another range of travel of said spring tensioned lever.

-2. Atimer comprising an escapement, a sprin tensioned lever for powering said escapement, means for coupling said lever to said escapement, a timing cam for efiecting uncoupling of. said lever from the escapement, said timing cam being shiftable into different positions of timing adjustment, a spring tensioned locking lever, companion toothed detent elements on said lockinglever and timing cam engageable in difierent relations in the 'difierent positions of said timing cam, said locking lever and said spring'tensioned lever having companion cam and roller elements engageable in the movement of said spring tensioned lever to effect release of said companion detent elements in one range of travel of said spring tensioned lever and to permit engagement of said companion detent elements in another range of travel of said spring tensioned lever, said cam element being in two sections, one section of a predetermined extent arranged to hold the detent elements separated for a predetermined time period and the other cam section adjoining said predetermined length cam section and arranged to permit engagement of the detent elements in the relation determined by position of the adjustable timing cam.

3. A timer comprising an escapement, a spring tensioned lever for powering said escapement,

means for coupling said lever to said escapement, a timing cam for effecting uncoupling of said lever from the escapement, said timing cam being shiftable into different positions of timing adjustment, a spring tensioned locking lever, companion toothed detent elements on said locking lever and timing cam engageable in different relations in the different positions of said timing cam, said locking lever and said spring tensioned lever having companion cam and roller elements engageable in the movement of said spring tensioned lever to efiect release of said companion detent elements in one range of travel of said spring tensioned lever and to permit engagement of said-companion detent elements in another range of travel of said spring tensioned lever, said cam element being in two sections, one section of a predetermined extent arranged to hold the detent elements separated for a predetermined time period and the other cam section adjoining said predetermined length cam section and arranged to permit engagement of the detent elements in the relation determined by position interval afforded by engagement of the roller with the first and second cam sections.

4. A timer comprising an escapement, a spring tensioned lever for powering said escapement, means for coupling said lever to said escapement, a timing cam for efiecting uncoupling of said lever from the escapement, said timing cam being shiftable into difierent positions of timing adjustment, a spring tensioned locking lever, companion toothed detent elements on said locking lever and timing cam engageable in different relations in the different positions of said timing cam, said locking lever and said spring tensioned lever having companion cam and roller elements engageable in the movement of said spring tensioned lever to effect release of said companion detent elements in one range of travel of said spring tensioned lever and to permit engagement of said companion detent elements in another range of travel of said spring tensioned lever, said detent elements including a toothed segment on said timing cam and a tooth on the locking lever engageable therewith and said companion cam and 6 roller elements including a roller on said spring tensioned lever and a cam face on said locking lever.

5. A timer comprising an escapement, a spring tensioned lever for powering said escapement, means for coupling said lever to said escapement, a timing cam for effecting uncoupling of said lever from the escapement, said timing cam being shiftable into difierent positions of timing adjustment, a spring tensioned locking lever, companion coupling elements on said locking lever and timing cam engageable in different relations in the different positions of said timing cam, said locking lever and said spring tensioned lever having companion cam and roller elements engageable in the movement of said spring tensioned lever to efiect release of said companion coupling elements in one range of travel of said spring tensioned lever and to permit engagement of said companion coupling elements in another range of travel of said spring tensioned lever.

LESTER E. PADELFORD.