US2641993A - Electric toaster - Google Patents

Description

June 16, 1953 D. w. MORPHY ET AL v ELECTRIC TOASTER 8 Sheets-Sheet 1 Filed Dec. 5, 1949 F/GZ.

I nveniorS PM W June 16, 1953 D. w. MORPHY EI'AL 2,641,993

ELECTRIC TOASTER Filed Dec. 5, 1949 8 Sheets-Sheet 2 o Inventors Daily/" 17 M n1 H llary/VX0850 Attorneys June 16, 1953 Filed Dec. 5, 1949 D. W. MORPHY ETAL ELECTRIC TOASTER 8 Sheets-Sheet 3 Inventors Dana! N. 017% A tlorney s June 16, 1953 D. w. MORPHY EI'AL 2,

} ELECTRIC TOASTER Filed Dec. 5, 1949 s Sheets-Sheet 5' Attorney 5 June 16, 1953 D. W. MORPHY'ETAL 2,641,993

ELECTRIC TOASTER Filed Dec.- 5, 1949 a Sheets-Sheet s I nvenlors 0011/ MM P anJ A /flam M- 190556;; 0 gw mw Attorneys 8 Sheets-Sheet 7 Filed Dec. 5, 1949 w I Aflomgy June 16, 1953 D. w. MORPHY EI'AL 2,641,993

ELECTRIC TOASTER Filed Dec. 5, 1949 8 Sheets-Sheet 8 filforneys v Patented June 16, 1953 ELECTRIC TOASTER Donal William Morphy, Chislehurst, and William Morris Russell, Slough, England, assignors to Morphy-Richards Limited, St. Mary Cray, England, a companyof Great Britain Application December 5, 1949, Serial No. 131,226

In Great Britain December 7, 1948 Claims. 1

"whereupon the bimetallic strip, on cooling, re-

turns to a position wherein it trips the latch thereby permitting the carrier to rise under the action of the loading spring and reopen the main switch to render the toaster inoperative. Thus, each timing cycle comprises a heating stage terminated when the bimetallic strip operates the subsidiary switch, followed by a cooling stage terminated when the bimetallic strip has returned to the automatic tripping position, that is to say when the temperature of the strip has fallen to the automatic tripping value.

In toasters of this kind, the duration'of each toasting period is usually preset by the operator who is then committed to the resulting degree 7 of toasting so that under-toasted or over-toasted slices delivered at the end of the toasting period may be wasted until the operator has, by trial and error, found the correct time setting. Ii, as in some instances, a manually operated trip device is provided so that the operator can trip the mechanism during an automatic timing cycle, recharging of the toaster is then liable to result in the residue of the previous or interrupted toasting period being continued until the next automatic trip occurs, thus delivering only partly toasted bread. The main object of the invention is to meet this difliculty.

An electric toaster according to the invention is provided with manually-operable tripping mechanism, and locking meanswhereby, after manual tripping, the toaster, even if relatched,

can again be renderedoperative only when the v temperature of the bimetallic strip does not exceed the automatic tripping value.

The invention may be carried into practice in various ways but one practical embodiment thereof is shown by way of example in the accompanying drawings, in which 1 Figure 1 shows the toaster in section on the line I-I of Figure 2,

. ure 1,

Figure 3 is a section on the line IIIIII of Figure 1,

Figure 4 illustrates, in elevation, the left-hand end wall of the interior frame included in Figure 1,

Figure 5 is a similar view of the right-hand end wall of the frame,

Figure 6 shows the timing mechanism on an enlarged scale and as viewed from right to left of Figure 1, with the hood removed,

Figure 7 is a plan of Figure 6, I

Figure 8 is a view from left to right of Figure 6,

Figure 9 is a view from right to left of Figure 6,

Figures 10 and 11 are views similar to that of Figure 9 but with parts cut away and the elements in difierent operative positions,

Figure 12 diagrammatically represents the electrical circuit of the toaster, and

Figure 13 is a bottom plan view of the toaster.

In the construction shown in the drawings, the toaster comprises a metal frame having two platelike vertical end walls, I, 2 secured at their lower v ends to two foot-strips 3, and at their upper ends to two longitudinal side strips 4 and two intermediate ties 5, 6. The side strips 4 and intermediate ties 5, 6 are mutually parallel and horizontally spaced apart with the two intermediate ties 5, B lying somewhat nearer to each other than to the side strips 4, as shown in Figure 3.

Each tie 5, 6 and side strip 4 is provided with two elongated slots 1 longitudinally spaced apart inthe strip and in which engage two tongues 8 at the upper edge of a metal reflector plate 9 having a plurality of vertical flutes or ribs l0 indented therein and'a flange ll along its lower edge. Three chambers are thus formed, namely two outer or toasting chambers 12 and a central mechanism chamber or chimney I3 (Figure 3). Lying spaced from the reflecting sides of the plates 9 are four mica formers l4 carrying heating elements, 15, I5, I1 and it connected in series (Figure 12), each toasting chamber I2 being thus bounded on two sides by two of the toasting elements respectively.

Each of the element formers is detachably held in position by two guard wires l9 each in the form of a U or hair-pin whose legs are undulated and whose apex or bend '20 is struck back to forma hook 21 adapted to engage in the corresponding slot 1 in the associated side strip 4 or intermediate tie 5, 6. Thus, the hooks 21 press the upper marginal portions of the formers [4 against the flutes It in the reflector plates 9, the lower extremities or prongs 22 of the guard wires l9 extending through apertures in the flanges H, with the lower edges of the formers l4 resting on the lateral extremities 22 at the lower ends of the guard wires I?! which bear against the lower marginal portions of the formers [4. In this way, the guard wires |9 serve not only as such but for detachably holding the reflector plates and formers M in their operative positions.

The four ends of the foot strips 3 are secured to two blocks 23, 24 of insulating material which form the two feet of the toaster, one foot 23 carrying the terminals 24 25,25,27, 28, 25 and 36 (Figures 2 and 12) of the electric power supply circuit energised through a flexible lead A, whilst the other foot 2 carries a base plate 3|. A hood 32 formed of sheet metal fits over the metal frame, as shown in Figures 1, 2 and 3, and is furnished at its lower edge with inwardly directed lugs 33 whereby the hood 32 is secured to the two feet 23, 24. The upper surface of the hood 32 is provided with two elongated openings 34, which regi'ster respectively with the two toasting chambers |2, a clearance 35 being provided between the metal frame and the hood 32 all round so that air can flow not only up through the chimney i3 and thence out through the elongated slots 35, but also between the inner surface of the hood 32 and the non-reflecting surfaces of the outermost reflector plates 9, to the said slots. The hood 32 is thus always maintained at a temperature sufficiently low to allow handling without discomfort.

Arranged beneath the metalframe is a crumb tray 36 hinged at 3? and having a flange 38 for cooperating with a spring-loaded releasable stop 39. The crumb tray 35 is provided with a central elongated slot 29 so that cooling air can flow through the said slot a3 and upwards through the chimney l3 to be discharged through the slots 3:5. Secured by studs 5| to the lower surface of the crumb tray 36 is a table shield 42 having apertures 43 which register with the central slot in the crumb tray 35. When, therefore, the pivoted crumb tray is in the closed position (as shown in Figures 1 and 3) air can flow upwards through the slots 53 in the table shield 42 and thence through the slot 4% in the crumb tray to the chimney l3, this vertical draught inducing an inward flow of air all round at 45 between the edge of the table shield 42 and the crumb tray 36. It will be seen from Figures 1 and 3 that the edges of the openings 46 as also the outer edges of the tray 36 are upwardly curved or deflected so as to tend to prevent crumbs being spilt from the tray and shield on to the table beneath. It will thus be apparent that in addition to the cooling of the hood 32 itself, as above described, the table or other supporting surface for the toaster is protected by the shield 42 against damage from radiant heat,

7 The hood 32 is provided on one side with a fixed handle 45 of heat-insulating material and on the other side with a central vertical slot 46 through which extends an operating lever 47 having secured to its outer end a handle 48 similar in appearance and of the same material as the fixed handle 45. The operating lever 47 is secured to a carrier plate 49 having integral lugs 58 rigidly connected respectively to two bread-carriers 5|, 52 which extend longitudinally within the two toasting chambers i2 (Figure 2) the bread carriers 5|, 52 being slidable through vertical slots 53 formed in the adjacent end wall of the frame. The carrier plate l?! is also connected through vertically'spaccd pivots 5d to the adjacent ends of two links 55, 56 which extend one above the other (Figure 1) through vertical slots 51, 58, 59 formed in the walls i and 2 at opposite sides of the chimney i3, the links 55 and 56 being connected to the wall 2 by spaced fixed pivots 60, 6|. Mountedtb turn about the fixed pivot BI is a crank 62 connected through a loading spring 63 to a lug 64 on the end wall the crank 62 carrying a loading arm 84 which extends through the chimney it so as to emerge through the vertical slot 5? beneath the carrier plate 45. Thus, when the operating handle 38 is pressed down, the two links55 and 55 are turned about their pivots 6i! and GI against the action of the loading arm 64, the bread-carriers ti and 52 simultaneously moving downwards within the toasting chambers I2.

The loading arm i5 normally holds the carrier plate 48 and the two bread carriers 5|, 52 in their raised positions shown in Figure l, but it should be noted that since the carrier plate 49 merely rests upon the loading arm 54, these two parts are independently movable vertically. When the carrier plate as is in its fully raised position it bears against two leaf springs 55, 58 secured to the end wall I and acting as resilient dampers to prevent shock when the carrier plate 49, after being released as described below, is raised from its lower or toasting position to its upper or delivery position. If desired a dash pot may be employed instead of the buffer springs 65, 66.

That end of the loading arm 54 adjacent to the carrier plate #19 is provided with an elbow 61, 68 (Figure 5) having insulating strip 69 carrying a spring strip Hi supporting two bridging contacts "5 i, 12 electrically connected together but insulated from the elbow 6?, 58 by the strip 59, the part 68 having a horizontal reset-control pin 13.

Mounted on the base plate 3| is a vertical pivot '54 (Figures 6 and '7) about which'can turn a bracket 15 connected by a stud it to a stop arm El and which. carries a horizontal pivot '53 for a bimetallic strip in, the stop arm ll, bracket '55 and bimetallic strip 79 together forming a hairpin like unit as viewed in Figure 7. Extending around the pivot "id is a coil-ed biassing spring 88 which tends to turn the stop arm ll towards a face cam 8|. The stop arm I? cooperates with the end of a normally fixed basic stop 82 carried by a vertical portion 83 of a mechanism plate 83 mounted on the base plate 3|, the stud 82 extending freely through a notch in the upper edge of the bimetallic strip it. The free end or" the stop arm 1'! lies between, and cooperates with, the fixed basic stop 82 and the time adjusting stop constituted by the face cam 8| which is rotatable in a vertical lug 8 of the base plate 3|, the spindle 85 of the cam 8| extending freely through an opening in the hood 32 to an adjusting knob 86 having an index or scale 81 for cooperating with a scale or index on the hood 32. The bimetallic strip 15 has an elongated slot 87 through which extends a stop rod 38 carried between the lug 8e and a flange B9 on the base plate 3|, the rod 88 thus limiting movement of the strip 19 about the pivot it. The bimetallic strip 19 carries a subsidiary electric heating element 90 secured to the bimetallic strip by metal straps 9|, and the mechanism plate 83 has a horizontal portion 92 which supports the two contacts 93, 94 of a main switch for controlling the power supply circuit, the contacts 93, 94 cooperating with the bridging contacts H, 72 on the loading arm 64 described above. The horizontal portion 92 of the mechanism plate 83 also supports a bifurcated plate 95 whose tines carry two fixed contacts 9B, 91. Two movable contacts 98, 99 carr ied by leaf springs I cooperate with the fixed contacts 96, 91, the contacts 98, 99 being mutually insulated by mica strips IN. The contacts 91, 99 constitute an auxiliary switch in series with the contacts 93, 94 of the main switch, and the contacts 96, 98 constitute a subsidiary switch for short-circuiting the subsidiary heating element 90 associated with the bimetallic strip I9. I

Mounted to turn on a horizontal pivot I02 carried by the mechanism plate 83 is a latch I93 whose free end I04 is normally urged upwards towards a fixed stop I by a spring I05, the latch I03 being engaged and turned downwards by the adjacent end I0I of the loading arm 54 when the operating handle 48 is pressed downwards in order to lower the bread carriers 5|, 52 into the toasting position. The latch I03 is thus-mounted independently of the loading arm 64. The

free end I04 of the latch I03 cooperates with a detent I05 (Figure 9) mounted to pivot at I00 against a coil spring I9I on a vertical bifurcated guide lug I08 carried by the base plate 3I, :the lower end I09 of the detent I05 being held by its spring I0I against a fiat on the projecting end of a horizontal pivot pin IIO interconnecting a crank I I I on the bifurcated lug I08 and a stepped latch-control lever II2 which lies in a vertical slot II3 formed in the bimetallic strip I9 near.

the free end thereof. The latch-control lever I I2 carries a stepped edge cam N4 of insulating material whose lower level 5 and higher level IEO respectively cooperate with the free ends of the two leaf springs I00 carrying the movable contacts 98 and 99.

A bell-crank lever III having one arm H8 pivoted on a horizontal pivot II9 on an upturned lug I of the base plate 3I is biassed by a spring I 2I so that its free arm I22 tends to move towards the adjacentend of the bimetallic strip 19. A pin I23 formed integrally with the pivot II9 extends through an elongated aperture III in the bell-crank lever II! and tends to move towards the wider end I24 of the latch-control lever II2. A resetting lever, in the form of a curved wire I25, is pivotally connected to the base plate 3| at I29 and has a crank I2I lying beneath the latch-control lever II2, the'upper or free end of the resetting lever'I25 being curved at I25 so as to lie in the path of movement of the reset control pin I3. The bifurcated lug;|08 has a lateral stop I08 which cooperates with a pivoted trip-control elbow I28 (Figures 1 and 2) having a transverse end portion I29 for cooperation with a spring-loaded manual trip button I30'carried by the hood 32. The elbow I28, when operated by the trip button I39, engages a lateral pin I3! on the detent I05 so as to move this out of engagement with the latch I03.

In the inoperative or. cold condition of the toaster, the loading spring 03 holds the loadin arm 64 in its raised position so that the said arm, in turn, holds the carrier plate 49 and toast carriers 5|, 52 in their uppermost or delivery positions within the toasting chambers I2 as shown in Figure l. .The latch I03 is now held by its control spring I05 against the associated fixed stop I05 whilst the trip-control elbow I28 rests, by gravity, against the fixed stop I08 Since the lower edge I33 of the stepped latch-control lever H2 is bearing against the edge of the bimetallic strip I9 within the slot I I3 thereof, the end of the moving contact 99 of the auxiliary switch, where- I by the latter remains closed as shown in Figure 9. Thus, though the contacts 91, 99 of the auxiliary switch remain closed, power is not supplied to the heating elements I 5I8 since the bridging contacts II, I2 on the loading arm 34 lie well above and clear of the fixed contacts 93, 94 of the main switch as shown in Figure 1.

Having inserted one or two pieces of bread through the slot or slots 34 so as to rest on the bread carriers 5| 52 respectively, the operating handle 48 is pressed down against the action of the loading spring 63. As the loading arm 64 moves down, the lateral reset-control pin I3 thereon engages the curved upper end of the resetting lever I25 so as to turn this about its pivot I26 in the clockwise direction as viewed in Fig ure 9. The cranked portion IZTI of the resetting lever I25 thus moves upwards against the lower edge I33 of the lever H2 so that the latter is raised and lifts the contact 99 to open the contacts 91, 99 as shown in Figure 11. As the reset-control pin I3 moves downwards beyond the curved part I25 of the resetting lever I25, thislever drops back in the counter-clockwise direction and allows the lever H2 to fall thereby reclosing the contacts 9I, 99 just before the bridging: contacts II, I2 close the contacts 93, 94 of the main switch. The supply circuit to the heating: elements I5I 8, including the subsidiary element 90 associated with the bimetallic strip I9, is thus established. Just prior to closing the main contacts 93, 94, the end I0I of the loading arm 04 V engages the pivoted latch I03 (as indicated in Figure 7) which is thus turned, against the action of its associated spring I00, until the free end I04 of the latch I03, guided by the fork at the upper end of the bifurcated guide lug I08, snaps into engagement beneath the detent I05, a claw I32 at the other end of the latch I03 simultaneously moving so as to lie over the loading arm 64 which is thus locked in its lowered position as shown in Figure 7.

If the cam 8| has been set for the shortest toasting period, there will be no gap between the cam 8| and the-stop arm II of the bimetallic strip 19. Under these conditions, when the lever 41 "has been lowered and the loading arm 94 latched so that the main contacts 93, 94 and the lever I I2 is raised sufficiently to cause the higher 7 auxiliary contacts 91, 99 are closed and the sub sidiary or short- circuiting contacts 90, 98 are open, current will flow through all the heating elements I5IB and 99. There will now be a preliminary period during which initial stress is taken up in the bimetallic strip I 9 which will not, therefore, as yet, move along the lower edge I33 of the latch-control lever II2. When this preload has been overcome, the free end of the bimetallic strip I9 will commence to move along the lower edge I33 towards the step I34 therein. As the bimetallic strip I9 moves, it is followed by the associated arm I22 of the bell-crank lever I i! which, however, will be arrested as soon as the bimetallic strip. I9 is moved near enough to the step I34 for the pin I23 to abut against the free end I24 of the lever H2 as shown in Figure 10.

' The bimetallic strip I9 now reaches the step I34 in the lever I I2 which therefore drops so that the short- circuiting contacts 96, 98 are closed and the heating element ofthe bimetallic strip I9 is deenergised, thereby terminating the heating stage of the automatic timing cycle. After a slight continued flexure of the bimetallic strip 19, the cooling part ofthe cycle commences, i; e. the strip I9 commences to return, to the left as viewed in Figures 9 to 11, and thus engages thestep I34 in the lever I I2 which is thereby drawn to the left to turn the detent I95 in the clockwise direction about its pivot SE6. perature of the strip 19 has fallen to the automatic tripping value, the strip reaches the automatic trip position corresponding to the end of the cooling part of the cycle and brings the detent Hi into a position in which it releases the latch m3 so that the free end I04 thereof rises and the claw I32 releases the loading arm t l which therefore rises under the action of the loading spring 63 to lift the loading arm 64, carriers 5i, 52 and toasted slices from the toasting position to the delivery position. As the loading arm Gd rises, the bridging contacts II, 12 first open the main contacts 93, 9 3 to deenergise the toasting elements I5--I3 whereupon the lateral reset-control pin '53 engages beneath the curved part i25 of the resetting lever I25 which is turned in the clockwise direction so that the crank 12! thereof lifts the lever I l2 thereby opening both the shortcircuiting contacts 95, 98 and the auxiliary contacts 9?, 9s. The pivoted detent m5 is now returned, by its control spring Iiil', to its initial position thus restoring the lever l 52 to the position shown in Figure 9. With continued upward movement of the loading arm 64, the lateral reset-control pin '13 passes over the curved part i25 of the resetting lever I25 which therefore drops back and permits the lever M2 to be relowered until its edge :33 again rests on the edge of the bimetallic strip I8 within the slot H3. The auxiliary contacts 9'1, 99 are thus reclosed though the main contacts 93, 54 and the shortcircuiting contacts 96, 98 remain open, the latter by reason of the associated contact strip Its resting on the higher portion IIB of the edgecam H (Figure 10). In this respect it should be noted that neither the auxiliary contacts 91, 99 nor the short-circuiting contacts 96, $8 at any time function to open the power circuit under load since this is carried out solely by the main contacts ii, I2 and 93, Q4 always opening before the auxiliary contacts 91, $59 are opened.

As the loading arm 64!. and carrier plate 49 approach their uppermost positions, i. e. to deliver the toasted slices through the slots 35, the carrier plate :19 bears against thedamping springs 85, 66 thus reducing the tendency for sudden arrest of, and shock to, the upwardly moving parts, and preventing over-vigorous upward delivery of the toast.

The first timing cycle thus consists of'three stages, namely a preliminary stage during which the preload on the bimetallic strip I9 is over-- come, a heating stage during which the bimetallic strip E9 moves up to the step I34 in the latchcontrol lever I52, and a, cooling stage during which the temperature of the bimetallic strip 79 drops to th automatic tripping value and thus moves the lever H2 back to the trip position. Both the heating and cooling stages take place exponentially, the automatic tripping temperature of the bimetallic strip 19 being somewhat higher than that at which the immediately initial heating stage commenced. Thus, if two further slices of bread are at once inserted and the operating handle 48 again depressed, the heating stage of the second timing cycle will commence at a temperature above that at-the comrnencement of the immediately preceding heating stage. Clearly, since the parts have not been allowed to cool down, there is no preload to be overcome and the second timing cycle will con- When the temsist of two stages only, namely a heating stage somewhat shorter than the heating stage of the first cycle followed by a cooling stage, substantially th same as the cooling stage of the first cycle, which brings the bimetallic strip 19 back to the trip position. If, after the second cycle has been completed and the toast delivered, the toaster is again charged with bread and the load arm 64 pressed down, the third timing cycle will take place over a period slightly shorter than the second.

If, with the previous setting of the cam 8| the toast delivered is not sufficiently browned, the cam 81 is adjusted by the operator so as to provide a clearance X (Figure 7) between the cam and the stop arm TI. If now toasting is again to commence from cold and the toaster is charged as described above, there will again be a preliminary stag during which the bimetallic strip is does not move, but takes up the preload or initial stress. Even after cancelling this preload, however, the bimetallic strip 19 will still not move along the lever H2 since there is some slight frictional load between the strip '59 and lever I I2 whereas the stop arm I! is free to move towards the cam 8 l. The bimetallic strip I9 still remains stationary, therefore, until the stop arm ll has crossed the gap X and bears against the cam 8|,

whereupon the bimetallic strip 19 commences to move along the edge I33 of the lever H2. The duration of the heating stage of the first timing cycle is thus increased by reason of the gap X which has to be taken up between the stop arm i! and the cam 8i. At the end of the heating stage of this first cycle the bimetallic strip 19 again reaches the step I34 in the lever I I2 which is thus moved down to close the short- circuiting contacts 96, 98 and thus to deenergise the heating element 99. As a result, the bimetallic strip 19 commences to cool, but the strip 19 itself will not move since there is some frictional load thereon whereas the sto arm I1 can move away from the cam 8I through the distance between the arm H and the basic stop 82. As the bi netallic strip l9 cools down, therefore, the arm l? thereof will first move away from the cam 81 until the arm 'I'I abuts against the basic stop 82 whereupon the strip '89 itself will move back, engage the step I34 in the latch control lever H2 and, having moved thi to the left as viewed in Figures 9 to 11, will release the detent I05 and trip the mechanism when the temperature of the bimetallic strip 2'9 has fallen to the automatic tripping value as before. It will be apparent that the larger the gap X between the stop arm I? and the cam 8i, that is to say the higher the time setting on the adjusting knobBG, the longer will be the timing cycle including th heating stage plus the succeeding cooling stage. As before, if two further pieces of bread are inserted in the toaster and the operating handle 33 again pressed down, the heating part of the second cycle will commence when the temperature of the bimetallic strip i9 is somewhat above that at a the resulting movement of the resetting lever I25 raises the lever I I2 and thus opens both the auxiliary contacts 91, 99 and the short- circuiting contacts 96, 98. Since the free end of the bimetallic strip 79 is now spaced away from the cooperating arm I22 of the associated bell-crank lever IE1, and the free end I25 of thelever H2 is raised above the level of the pin i223 on the bell-crank lever I I1, this lever will turn until the pin I23 lies under the free end of the latch control lever II2 i. e. against the dge I33. When, therefore, the loading arm 64 rises to its uppermost or delivery position, though the resetting lever I25 drops back, return of the latch-control lever II2 is prevented by the pin I23 of th bell.- vcrank lever II'I. Thus, the auxiliary contacts 91, 99 will be maintained open so that even if the toaster is immediately recharged and the operating handle 48 pressed down to close the main contacts 93, 94 and relatch the loading arm 64, the power circuit will remain open at the auxiliary contacts 91, 99. The next toasting cycle cannot therefore begin until the bimetallicstrip I9 has cooled down to the automatic tripping temperature, that is to say until the strip I9 has moved back to engage the arm I22 of the bellcrank lever II! and thus to move the pin i223 out from beneath the lever I I2 which then drops down thus closing the auxiliary contacts 5?, 99

but leaving the short- circuiting contacts 95,98

open. The arrangement is such that the lever H2 is released by the pin I23 when the temperature of the bimetallic strip 19 has fallen to the automatic tripping value and the bimetallic strip 'I9 has reachedthe tripping position. 7

It will be apparent, therefore, thatthough the toaster has been tripped at random and during a timing cycle, immediate recharging and relatching of the toaster will not result in the remainder of that cycle being applied to the next slices, with consequentunder-toasting, since the next cycle cannot commence until the bimetallic strip 19 has moved back to the automatic tripping position whereupon the next timing cycle will commence automatically.

In the event of the toast as delivered when the toaster is tripped automatically at the end of a complete timing cycle being insufficiently browned, th operator merely presses down the operating handle 48 again so that the next cycle commences at the beginning of a heating stage and, after applying an additional toasting period to the bread (which may be checked by raising the handIeAB'and carriers 5|, 52) the operator presses the manual trip button I30, Here again, the toaster can beimmediately recharged, with: out risk of a shortenedcycle being thereupon app-lied to the bread sincethe manual trip, has, as above described, left the latch-control lever I I2 in the raised position with the auxiliary contacts 91, 99 openso that the next timing cycle can only commence when thebimetallic strip 119 has returned to the normal tri position. Y, t

It will be apparent that the, operator, having found that with the timing cycle as set bythe cam 8| the bread is undertoasted or overtoasted at the termination of a cycle, orbegins to smoke before such termination, will adjust, the said cam to rectify the next succeeding cycle. -Whatever hi setting, however, heis not committed thereto since, after manually raising the, carriers BI, 52 (without disturbing the timing cycle in to the newly inserted slices.

. and that details may be modified to suit requirements.

What we claim as our invention and desire to secure by Letters Patent is:

1. An electric toaster comprising at least two supports mutually spaced to provide a toasting space between them, electric toasting elements carried by the supports, a bread carrier disposed within said space, a loading spring biassing the carrier froma toasting position towards a delivery position, a main switch controlling the continuity of the toaster circuit which includes said toasting elements, means whereby said main switch is closed by the cocking of said spring,'a latch, means operatively connected to the spring and engaged by the latch to retain the spring in its cocked condition, an auxiliary switch controlling the continuity of said toaster circuit, a subsidiary heating element, a temperature-responsive device associated with the subsidiary heating element, a subsidiary switch controlling the energisation of the subsidiary element, a latch-control member actuated by said temperature-responsive device and operatively connected to the latch, subsidiary switch and auxiliary switch, cooking of said spring thus closing the main switch and engaging said latch whereupon the temperature-responsive device, after a predetermined response, operates the subsidiary switch to deenergise the subsidiary heating element, the temperature-responsive device, on cooling, returning to an automatic tripping position wherein it trips the latch so that the spring moves the carrier to the delivery position and opens the main switch, a manually'operable tripprogress) if toasting is already adequate, hecan v manually trip the mechanism, reset the cam 3| to give a second and shorter toasting period and ping deviceassociated with the latch, and locking means cooperating with the latch-control member, manual tripping of the latch causing said locking means to engage and lock the latchcontrol member in a position in which it retains the auxiliary switch open until th temperatureresponsive device, on its return to the automatic tripping position, engage and moves the locking means out of engagement with the control member.

2. An electric toaster comprisingat least two supports, mutually spaced to provide a toasting space between them, electric toasting elements carried by'the supports, a bread carrier disposed within said space, a loading spring biassing the carrier from a toasting position to a delivery position, a main switch controlling the continuity of the toaster circuit which includes said toasting elements, means whereby said main'switch is closed by the cooking of said spring, a latch, means operatively connected to the spring and engaged by the latch to retain the spring in its cocked condition, an auxiliary switch controlling the continuity of said toaster circuit, asubsidiary heating element, a temperature-responsive:device associated With the subsidiary heating ele ment, a subsidiary'switch controlling the energisation of the subsidiary element, latch-control means actuated by said temperature-responsive device and operatively connected to the latch, auxiliary switch and subsidiary switch, cocking of said spring thus closing the main switch and engaging said latch whereupon the temperatureresponsive device, after a predetermined response, operates the subsidiary switch to deenergise the subsidiary heating element, the temperature-responsive device, on cooling, returning to an automatic tripping position wherein it trips the latch so that the spring moves the carrier to the delivery position and opens the main switch,

a manually operable tripping device associated with the latch, and locking means cooperating withthe latch-control means and which, after manual tripping of the latch, holds the auxiliary switch open unless and until the temperature of the temperature-responsive device does not ex ceed that corresponding to the said automatic tripping position of the temperature-responsive device.

3. An electric toaster comprising at least two supports mutually spaced to provide a toasting space between them, electric toasting elements carried by said supports, a bread carrier disposed within said space, a loading spring biassing the carrier from a toasting position towards a delivery position, a main switch controlling the continuity of the toaster circuit which includes said toasting elements, means whereby said main switch is closed by the cooking of said spring, a latch, means operatively connected to the spring and engaged by the latch to retain the spring in its cocked condition, a subsidiary heating element, a temperature-responsive device associated with the subsidiary heating element, a subsidiary switch controlling the energisation of the subsidiary element, the subsidiary switch, when closed, short-circuiting the subsidiary element, an auxiliary switch controlling the continuity of said toaster circuit, a latch-control member actuated by said temperature-responsive device and operatively connected to the latch and to the subsidiary and auxiliary switches, cocking of said spring closing the main switch and engaging said latch whereupon the temperature-responsive de vice, after'a predetermined response, closes the subsidiary switch to deenergise the subsidiary heating element, the temperature-responsive device, on cooling, returning to an automatic tripping position wherein it trips the latch so that the spring moves the carrier to the delivery position, a resetting device associated with the latch-control member, means operated by said spring and engaging the resetting device whereby, when said latch is released, the resetting device is actuated and moves the latch control member to open both the subsidiary and auxiliary switches, a manually operable tripping device associated with said latch, and locking means operatively associted with the temperature-responsive device and latch-control member, manual tripping of the latch thus causing the main, auxiliary and subsidiary switches to be opened whereupon recocking of the spring to reengage the latch recloses the main switch whereas the latch-control member is held by the locking means in a position in which it preventsreclosing of the auxiliary switch until the temperature-responsive device returns to a position in which it engages and moves the locking means out of engagement with the latch-control member.

4. An electric toaster comprising at least two supports mutually spaced to provide a toasting space between them, electric toasting elements carried by said supports, a bread carrier disposed within said space, a loading spring biassing the carrier from a toasting position to a delivery po sition, a main switch controlling the continuity of the toaster circuit which includes said toasting elements, means whereby said main switch is closed by the cooking of said spring, a latch, means operatively connected to the spring and engaged by the latch to retain the spring in its cocked condition, an auxiliary switch controlling the continuity of said toaster circuit, a subsidiary heating element, a temperature responsive device associated with the subsidiary heating element, a subsidiary switch controlling the energisation of the subsidiary element, a pivoted latch-com trol member actuated by said temperature-responsive device and operatively connected to the latch, subsidiary switch and auxiliary switch, cooking of said spring closing the main switch and engaging said latch whereupon the tempera ture-responsive device, after a predetermined response, operates the subsidiary switch to deenergise the subsidiary heating element, the temperature-responsive device, on cooling, returning to an automatic tripping position wherein it trips the latch so that the spring moves the carrier to the delivery position thereby opening the main switch, a resetting member cooperating with the latch-control member, means operatively connected to said spring and cooperating with the resetting member, automatic tripping of said latch thus causing said spring to act through the resetting member on the latch-control member which is turned about its pivot to open the subsidiary switch and to open and reclose the auxiliary switch, recocking of the spring turning said latch-control member to open and reclose the auxiliary switch and closing the main switch, a manually operable tripping device associated with the latch, and locking means cooperating with the temperature-responsive device and latch control member, manual tripping of the latch causing said locking means to engage and lock the control member in a position in which it retains the auxiliary switch open until the temperatureresponsive device, on its return to the automatic tripping position, engages and moves the locking means out of engagement with the latch-control member.

5. An electric toaster comprising at least two supports mutually spaced to provide a toasting space between them, electric toasting elements carried by said supports, a bread carrier disposed within said space, a loading spring biassing the carrier from a toasting position to a delivery po sition, a main switch controlling the continuity of the toaster circuit which includes said toasting elements, means whereby said main switch is closed by the cooking of said spring, a latch, means operatively connected to the spring and engaged by the latch to retain the spring in its cocked condition, an auxiliary switch controlling the continuity of said toaster circuit, a subsidiary heating element, a temperature responsive device associated with the subsidiary heating element, a subsidiary switch controlling the energisation of the subsidiary element, latch-control means actuated by said temperature-responsive device and operatively connected to the latch, subsidiary switch and auxiliary switch, cooking of said spring closing the main switch and engaging said latch whereupon the temperature-responsive device, after a predetermined response, operates the subsidiary switch to deenergize the subsidiary 13 heating element, the temperature-responsive de vice, on cooling, returning to an automatic tripping position wherein ittrips the latch, a reset member associated with said latch-control means, means operatively connected to said loading spring and cooperating with the reset member, so'that when the latch is tripped the spring moves the carrier to the delivery position, opens the main switch and then acts through the reset member on the latch-control means to open the auxiliary switch, a manually operable tripping device associated with the latch, and locking means cooperating with the temperature-responsive device and latch control member, manual tripping of the latch causing said locking means toengage and lock the latch-control member in a position in which it retains the auxiliary switch open until the temperature-responsive device, on its return to the automatic tripping position engages and moves the locking means out of engagement with the latch-control member.

1 6. An electric toaster comprising at least two supports mutually spaced apart to provide a toasting space between them, electric toasting elements carried by the supports, a bread carrier disposed within said space, a loading spring biassing the carrier from a toasting position towards a delivery position, a main switch controlling the continuity of the toaster circuit which includes said toasting elements, means whereby said main switchis closed by the cooking of said spring, a latch,- means operatively connected to the spring and engaged by the latch to retain the spring in its cocked condition, a subsidiary heating element, a temperature-responsive device associated with the subsidiary heating element, a subsidiary switch controlling the energisation of the subsidiary element, the subsidiary switch when closed, short-circuiting the subsidiary element, an auxiliary switch controlling the continuity of said toaster circuit, a latch-control member actuated by said temperature-responsive device and operatively connected to the latch and to the subsidiary and auxiliary switches, cooking of said spring closing themain switch and engaging said latch whereupon the temperature-responsive device, after a predetermined response, closes the subsidiary switch to deenergise the subsidiary heating element, the, temperature-responsive device, on cooling,,returning to an automatic tripping position wherein it trips the latch, so that the-spring moves the carrier to the delivery position, a resettingmdevice associated with the latch-control member, means operated by said spring whereby, when said latch is released, the resetting device is actuated and moves the latchcontrol member to open both the subsidiary and auxiliary device associated with said latch, and locking means associated with the temperature-responsiVe device and latch-control member, manual tripping of the latch thus causing the main, auxiliary and subsidiary switches to be opened whereupon recocking of the spring to reengage the latch recloses the main switch whereas the latch-control member is held by the locking means in a position in which it prevents reclosing of the switches, a manually operable tripping auxiliary switch until the temperature-responsive element returns to a position in which it engages and moves the locking means out of engagement with the latch-control member.

7. An electric toaster comprising at least two supports mutually spaced to provide a toasting space between them, electric toasting elements carried by the supports, a bread carrier disposed within said space, a manually operable handle extending from the carrier, a pivoted loading arm arranged within the toasting space, said carrier resting on the loading arm, a loading spring biasing said arm towards the carrier thus tending to move the carrier from a toasting position towards a delivery position, a main switch controlling the continuity of the toaster circuit which includes said toasting elements, means whereby said main switch is closed by the cocking of said spring, a pivoted latch carried by the base, a spring 'biassing said latch, a pivoted lever cooperating with the latch, a spring biassing the lever towards the loading arm, a retaining lug carried by said lever and cooperating with the loading arm, an auxiliary fixed contact carried by the base, an auxiliary movable contact cooperating with the auxiliary fixed contact to control the continuity of the said toaster circuit, a subsidiary heating element in series with the toasting elements, a bimetallic strip associated with the subsidiary heating element, a subsidiary fixed contact carried by the base, a subsidiary movable contact cooperating with the subsidiary fixed contact to short-circuit the subsidiary heating element, a stepped latch control member pivotally connected to said latch, a reset lever mounted to pivot on said base, acrank carried by said reset lever and lying beneath thelatch control lever, a reset pin carried by the loading arm and co operating with the reset lever, a switch-actuating member carried by the latch-control lever and cooperating with said auxiliary and subsidiary movable contacts, a manually operable trip lever carried by the base and cooperating with said latch, a pivoted stop lever carried by the base and operatively connected to said bimetallic strip, a cam cooperating with said stop lever, means for adjusting the cam to determine the spacing between the cam and the stop lever, locking means comprising a bell-crank lever, a pivot connecting one arm of said bell-crank lever to the base, a spring biassing the other arm of the bell-crank lever into contact with the bimetallic strip, and an abutment carried by said bell-crank lever and cooperating with the lower edge of said latchcontrol member, manual tripping of said latch causing the reset pin to turn the latch-control member thus opening the auxiliary contacts and raising the lower edge of the latch-control member above the level of said abutment which thus moves so as to lie beneath the said lower edge thereby preventing reclosing of the auxiliary contacts until the bimetallic strip, on cooling, engages the bell-crank lever to move the abutment out of engagement with the latch-control lever.

8. An electric toaster as claimed in claim 1, having means whereby tripping of the latch, whether automatic or manual, causes the main switch to open before opening of the auxiliary switch so that opening of the toaster circuit under load is effected solely 'by the main switch.

9. An electric toaster comprising at least two supports mutually spaced to provide a toasting space between them, electric toasting elements carried by the supports, a bread carrier disposed Within said space, a loading spring biassing the carrier from a toasting position to a delivery position, a main switch controlling the continuity of the toaster circuit which includes said toasting elements, means whereby said main switch is closed by the cooking of said spring, a latch, means operatively connected to the spring and engaged by the latch to retain the spring in its cocked condition, an auxiliary switch controlling 115 the continuity of said toaster circuit, a subsidiary heating element, a temperature-responsive device associated with the subsidiary heating element, a subsidiary switch controlling the energisation of the subsidiary element, a latchcontrol member actuated by said temperatureresponsive device and operatively connected to the latch, subsidiary switch and auxiliary switch, cocking of said spring thus closing the main switch and engaging said latch whereupon the temperature-responsive device, after a predetermined response, operates the subsidiary switch to deenergise the subsidiary heating element, the,

temperature-responsive device, on cooling, returning to an automatic tripping position wherein it trips the latch so that the spring moves the carrier to the delivery position and opens the main switch, a manually operable tripping device associated with the latch, a locking device, a spring biassing the locking device into contact with said temperature responsive device, an abutment carried by the locking device and cooperating with the latch control member, the locking device moving with the temperature-responsive device until the abutment engages the latch control member and arrests further movement of the locking device, a resetting member associated with the latch-control member, and means operatively connected to the loading spring and actuating said resetting member whereby the latch control means is moved relatively to said abutment when the latch is tripped, manual tripping of the latch thus causing said abutment to lock the latch control member in a position correspending to the open position of the auxiliary switch until the temperature-responsive device returns to the automatic tripping position wherein the temperature-responsive device reengages the locking device and moves said abutment out of locking engagement with the latch-control member.

10. An electric toaster comprisin at least two supports, mutually spaced to provide a toasting space between them, electric toasting elements carried by the supports, a bread carrier disposed within said space, a loading spring biassing the carrier from a toasting position towards a delivery position, a main switch controlling the continuity of the toaster circuit which includes said toasting elements, means whereby said main switch is closed by thecocking of said spring, a latch, means operatively connected to the spring and engaged by the latch to retain the spring in its cocked condition, a subsidiary heating element, a temperature-responsive device associated with the subsidiary heatin element, a subsidiary switch controlling the energization of the subsidiary element, latch-control means actuated by said temperature-responsive device and operatively connected to the latch and subsidiary switch, cooking of said spring thus closingthe main switch and engaging said latch whereupon the temperature-responsive device, after a predetermined response, operates the subsidiary switch to de-energize the subsidiary heating element, the temperature-responsive device, on cooling to a predetermined temperature, returning to an automatic tripping position in which it trips the latch, a manually operable device for tripping said latch while said temperature-responsive means is above said predetermined temperature, an auxiliary switch in series with said main switch, means operating upon tripping of said latch to open said auxiliary switch, and locking means responsive to movement of said temperature-responsive means to prevent reclosure of said auxiliary switch while said temperature-responsive device is above said predetermined temperature, said temperature-responsive device carrying a stop arm lying between, and cooperating with, a normally fixed basic stop and a time adjusting stop, initial movement of the temperature-responsive device at the beginning of the timing cycle and at the beginning of the cooling stage thereof being delayed in accordance with the lost motion available between the stop arm and the adjustable and fixed stops.

DONAL WILLIAM MORPHY. WILLIAM MORRIS RUSSELL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,196,393 Ireland Apr. 9, 1940 2,229,945 Uhlrig Jan. 28, 1941 2,254,946 Ireland Sept. 2, 1941 2,288,699 Gomersall et a1 July 7, 1942 2,302,117 Gomersall Nov. 17, 1942 2,315,327 Gomersall Mar. 30, 1943 2,363,169 Fischer Nov. 21, 1944 2,367,044 Newell Jan. 9, 1945 2,494,373 Young Jan. 10, 1950 2,508,464 McCullough May 23, 1950 2,542,231, Campbell Feb. 20, 1951 2,585,465 Humphrey Feb. 12, 1952

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