Timer structure

Abstract

Claims

`uly 16, 1940. R. sARDEsoN TIMER STRUCTURE Filed NOV. 29, 1957 2 Sheets-Sheet l Rober- Sardeson. July i6, 1940. R. sARDEsoN 2,207,947 TIMER STRUCTURE Filed NOV. 29, 1937 2 Sheets-Sheet 2 Invenor: Robert' Saroleson BH 45M @y Patented 194() PATENT OFFICE TIMER STRUCTURE Robert Sardeson, Minneapolis, Minn., assignor to McGraw Electric Company, Chicago. IIL, a. corporation of Delaware Application November 29, 1937, Serial No. 177,137 6 Claims. y to provide a relatively simple and compact selfcontained timer structure adapted for association with a toasting or cooking chamber and to provide a unitary mechanical timer structure having means to selectively release a latched mechanism y after a pre-determined time interval or after a variable time interval. Other objects of the invention will more fully appear from the following description and the accompanying drawings and will be pointed out in the annexed claims. In the drawings, Fig. 1 is a view mainly in side elevation, but partly in section, of a mechanical timer embodying my invention, Fig. 2 is a vertical sectional view therethrough taken on the line 2 2 of Fig. 1, Fig. 3 is a view similar to Fig. 1 showing parts of the timer in the positions occupied by them just after the spring has been wound up and at substantially room temperature, Fig. 4 is a view similar to Fig. 3 but showing the positions of the parts when the thermostat is heated and just after release of the latch, Fig. 5 is a view mainly in side elevation, but partly in section, taken from the opposite side of that of Fig. 1, Fig. 6 is a view in horizontal section therethrough taken on the line 6 6 of Figs. 1 and 5, and Fig. 7 is a view in horizontal section therethrough taken on the line 1-1 of Fig. 5. The device embodying my invention is particularly applicable for use with toasters and the device shown in the drawings has been developed with reference to such use. I do not however desire to be restricted to such use as my device is adapted. to other similar toasting, cooking or heat treating devices. The device embodying my invention is particularly useful in appliances in which substantially the same operation is to be effected a number of times in succession. A timer structure designated generally by the numeral II includes a rear side plate I3 and a front side plate I5 which plates are spaced apart and held by spacing rods I 1, any desired number or which may be utilized and I have shown four such spacing rods. A power device includes a spring I9 which is substantially the same as those used in clock mechanisms, one end of spring I3 being suitably.- 5 secured to a pin 2l on plate I3 while its other end is secured to a spring shaft 23 which is rotatably mounted in the two plates I3 and I5 in a manner well known in the art. Spring shaft 23 has mounted thereon a ratchet wheel 25 and a pair lo of pawls shown generally only in Fig. 2 of the drawings, as well as a spur gear 2l'. No detailed showing is made of the pawls since they are old in the art and operate in the usual manner. Spur gear 21 meshes with a pinion 29 which is rigidly :15 connected with a second spur gear 3 I, both pinion 29 and gear 3| being secured on a second shaft 33 rotatably mounted in the fra-me structure including the plates I3 and I5. Spur gear 3i meshes with a pinion 35 :fixedly mounted on a third shaft 31 which shaft has xedly mounted thereon a spur gear 39, meshing with a pinion 4I mounted on a crank shaft 43 having a crank pin 45. Crank pin H5 has connected therewith one end 25 oi' a connecting rod 41 the other end of which is connected to one end oi a lever arm 49 loosely mounted on a shaft 5I which may be rotatably supported in the plates I3 and I5 and which has iixedly mounted thereon a balance wheel 53. A 30 small helical spring connects the other end of the lever arm 49 with the outer peripheral portion of the balance wheel 53. The details of this balance wheel and its connection with the connecting rod 81 constitute no part of my present 35 invention but are disclosed and claimed in my copending application Serial No. 152,580, led July 8, 1937, and assigned to the same assignee as is the present application. Y Spring I 9 can be wound up by means to be o hereinafter described and is then adapted to unwind, causing rotation of the spur gears and pinions and reciprocating movement of connecting rod 41 with reciprocal turning movement of the balance wheel 53, the spring being'adapted to 45 unwind to substantially its initial condition in a given time interval, that is the mechanical timer thus far described is a constant speed timer. While I have illustrated and described a spring driven timer, my invention is not limited thereto 50 and any equivalent power means, e. g., an electric motor, may be used instead of the spring. Means for winding up the spring I9 includes a pinion 51 xedly mounted on spring shaft 23 at that end thereof opposite to the end to which 55 thereof. spring I9V is connected. A reciprocally movable -rack bar 59 meshes with pinion 51 and is held in engagement therewith by a grooved roller 6| rotatably mounted on plate I5. At the lower end of rack bar 59 are mounted a ratchet wheel 63 and a spur pinion 65 xedly secured to each other but. rotatable relatively to the rack bar 59 by their mounting on a pin 51. The normal or ,inoperative position of rack bar 59 is substantially 10 that-shown in Figs. 1, 2 and 5 of the drawings, that is in an upward position, suitable stop means being provided to prevent extreme or undesired unwlnding of the spring I9 which of course must have some tension even when the timing mechanism is in ,its run-down or normal inoperative position. 1, A vertically extending rod or standard 69 is supported by plate I5 and is spaced a suitable distance away from this plate and may be supj ported by laterally extending lugs 'Il and 'I3 integral with plate I5. While I have shown a particular form of supporting means for 'the standard'99 I do not desire to be limited thereto. It may be here pointed out that I prefer to make the standard .69 ofv a cross sectional form other than circular in order to prevent other mechanism slidably mounted thereon from having any appreclable turning movement relatively `to the timer structure. while permitting reciprocal a0 movement thereof on the standard 69. An actuating means for moving the rack bar downwardly and simultaneously winding up the spring includes a carriage I5 having a heat- ,insulating actuating knob 'Il at the front end The carriage 15 may include an intermediate' portion having a. contour complementary to that of the cross sectional area of the'standard 69 and surrounding and closely engaging the standard, a forwardly-extending por- 'w vtion on which knob 'I1 is mounted and a rearwardly-extending portion 'I9 although I do not desire to be limited to this particular design. The rearwardly extending portion I9 of the carriage has a cam 8| mounted thereon at its inner face, which cam is of substantially triangular form particularly as to its outer surface, while it is` provided with a recess 83 in its bottom sur- .face (see Fig. 4) having therein a downwardly projecting tooth 85. When carriage 'I5 is moved downwardly tooth 85 will engage in oneoi. the ` spaces between the teeth of pinion 65. for a purpose to be` hereinafter referred to. As it is an object of my invention to provide a 55 controller timerwhich may be actuated either manually or in any other way to initiate a toasting or cooking operation or to wind up or energize the .power means exemplified here by spring I9 so that van element of an appliance may be actuated, moved or released after a time interval, 4I have illustrated such an element by a slidable member 81 comprising a tubular member iitting around the standard '59. As shown slider 87 is positioned below carriage 'I5 and is adapted to be biased to its normal upper posi- Y tionby a spring 89 one end of which is suitably connected to a lug on slider 81 while the other end is connected toa fixed part of plate I5 at the upper end thereof. I preferably locate the spring 89 between the standard 69 and plate |5. While I have shown a relatively simple slider member 81 I desire it to be understood that this showing is general and is to lrepresent any-element or means which is to be reclprocally movable in order to Acarry out any heating opera- 2,171,895 granted Sept. 5, 1939. tion requiring a time interval to eiiect the same, such as a bread slice support in a toaster. A plural arm latching means 9| is pivotally mounted onplate I5 as by a xed pin 93 and includes a substantially vertically extending arm 95, a substantially horizontally extending arm 91 and a detent shoulder 99 at or near the junction of thetwo arms. Slider 91 is provided with a tooth or projection I0| adapted to be moved underthe detent shoulder 99 to thereby hold slider 31 and any other parts connected therewith in an operative position. The upper end of arm 95 has a pin |03 extending laterally from its outer face which pinis adapted to be engaged by one of the outer surfaces of cam plate 8| during upward movement of the rack bar and the cam plate, this position being shown in Fig. V4 of the drawings. Latch 9| is adapted to be held normally in the position shown in Fig. 3 by a spring |05 the design and construction being suchthat tooth IBI on mechanism 91 can ride past the detent shoulder 99 during downward movement thereof and then under shoulder 99 to be held thereby until releasedby turning movement of latch 9|. It is-obvious from the drawings and from the description thus far that downward pressure on knob 'I'I by an operator effects downward -movement of carriage 15, element 81 and of rack bar 59. 'I'his downward movement is continued until, as has just beenexplained, toothv IIII is tinuing until carriage 'l5 abuts against a stop pin |07 on standard 69. It is further obvious` that element 91 may be released from theY latch before it would normally be released by engagey ment of cam 9| with pin |93, by an upward` movement of carriage I5 by an operator, which upward movement if continued until-cam 9|. engages pin |93 will eiect release of mechanism 87 from latch 9B. Y ,As it is desirable if not necessary in certain l cases, to provide thermal means to cause release of the latch after a shorter time interval whenV a timer of this kind is associated with a toaster, I provide a bimetal element III which is preferably though not necessarily of the kind disclosed and claimed in my copending application Serial No. 127,100 now Patent No. This bimetal element includes 'a main bar IIB and an auxillary or compensating bar ||5 the element being supported by the inner end of bar'IIS on a bracket arm III. This bracket arm isl adjustably mounted against side plate I3, its form being shown particularly in Fig. 5 of thedrawings outer face of plate I3. At its lower end bracket arm II'I is provided with a laterally extending portion |29 (see Figs. 6 and 1) extending through plate I3, the edge face of which is provided with teeth meshing with a pinion |3I mounted on a lmanually adjustable shaft |33 having an'adjusting knob |35thereon. I When bimetalelement ||I is at normal or room temperature it will be substantiallyfiat or straight as shown in Fig. 5 of the drawings. The movable end I| 3 of bimetal element is adapted to engage one arm |3`| of an offset bellcrank lever comprising, in addition to arm |31 adjacent to plate I3 a second arm |39 adjacent to plate I5 and a pivot pin I4| which pivot pin is mounted in the two plates I3 and I5 in such manner that it may turn relatively thereto. Arm |39 has a roller |43 mounted thereon at its outer end which roller is adapted to engage with a ratchet lever pivotally mounted on the outer end of latch arm 9`| which ratchet lever is biased in a given direction by spring |41. As shown more particularly in Fig. 1 of the drawings a limit of turning movement of ratchet lever |45 is xed by a stop pin |49 engageable by arm |31 of the bellcrank lever. In the normal position of ratchet lever |45, it and particularly the toothed edge |5| of the lever is out of the path of the return movement of ratchet wheel 63 but 'when bimetal element Iii exes in the manner4 shown in Fig. 4 of the drawings, ratchet lever |45 is caused to turn in a clockwise direction (as seen in Figs. 1, 3 and 4) so that it is in the path of return movement of ratchet wheel tI-i. . As has already been hereinbefore stated tooth 85 of cam 8| is in engagement with pinion 65 during .the downward movement of carriage 'l5 and of rack bar. 59 but in addition thereto' this interlocking of the tooth and the pinion continues during the return or upward movement or" carriage 'i5 caused by the unwinding of spring iii and transmission of such movement through pinion 5l to rack bar 59 to cause upward movement of the latter. ment of ratchetlever |45 and ratchet wheel occurs, ratchet lever |635 is carried or moved in a generally upwardly direction thereby causing a turning movement of plural arm latching means 9| about its pivot 93 in a manner to ei'r'ect release of mechanism represented by slider til theren from with consequent quick upward movement of element @l and carriage i5 because o spring it is further evident that as soon as slider @l engages with carriage l5 the latter is moved quickly upward independently of the relatively slow movement of rack bar 5@ so that tooth 35 is disengaged from pinion t5 whereby turning movement of ratchet wheel t3 and pinion tt on their supporting pin is permitted so that ratchet Wheel t3 can travel idly along ratchet lever and so that the spring it may unwind fully if permitted to do so by the operator who may of las. rf knob ist is turned to effect downward' movement of bracket varm i il and of bimetal element the latter will be caused to engage arm |37 sooner than wouldvbe the case if bracket ill! and bimetal arm iii were moved upwardly. Turning movement of ratchet lever M5 into engagement with ratchet wheel B3 and consequent actuation of latching means tl and release of element 31 will therefore be eiected sooner than would otherwise be the case. It is evident therefore that release or' element 8l may be eected It is thus evident that, when engage` either at the end of a iixed time interval as when the thermostat I II remains at its normal or room temperature, in which case the detent is moved by engagement of cam plate 8| with pin |03. Release o1' the latch or detent may be effected after a shorter time interval, the length of which decreases with increase of temperature of bimetal element |I|, this release being effected by movement of ratchet lever |45 in a generally upward direction when engaged with ratchet wheel 83 while the latter is being moved upwardly and its rotation prevented. This elevation of lever |45 rocks the plural arm latch 9| by reason of the pivotal connection of lever |45 with the second latch arm 91. It is obvious that a variable speed timer may be used in place of the constant speed timer shown, without departing from the essence of the invention. I have shown, in certain of the figures of the drawings, a device or appliance with which the unitary timer hereinbefore described :may be operatively associated, having a base i53 and the timer as provided with integral depending portions |55 on one or more of its side plates. These portions v|55 are adapted to extend through suitable .openings in the upper flat part of base 53 ,to thereby interlock the timer structure with the device.V It may here be pointed out that the device disclosed and claimed in the present application diiers incertain essential details from other similar devices in that the timer structure is a unitaryv or self-contained one supporting not only the thermal element but also a standard on which is slidably mounted a carriage as well as an elenient orrnernber adapted to be held in predetermined latchedposition during an operation and to be released after a predetermined or variable timeinterval. in case the device embodying my invention is applied to a toaster, the elementi@ may be the bread slice support. am fully aware of other mechanisms, for instance toasters in which the toaster structure itself carries the lstandard or standards on which a carriage is slidably mounted and on which standards are also mount- 5ed bread slice supports or means connected to bread slice supports. lThe device embodying roy invention thus provides a simplified construction eective ior the same purposes as the earlier devices referred to hereinbefore but has the adn vantage ci greater adaptability for association with other cooking devices and can be inserted therein or mounted thereon and removed there from as a unit. The timer assembly can be assembled as a unit and tested as to its operation, before being mounted in or on an appliance to be controlled thereby. lt may be further pointed out that the use of a standard having a cross sectional form other than circular permits of using only a single standard which will have the necessary directive effect of holding the reciprocable mechanism, which may be a bread slice support when the timer assembly is operatively associated with a toaster, in proper operative relationship relatively to the toaster. i'lihis maires lior ease in assembly of the timer on and with a cooking or toasting device. it is evident that modifications maybe made in the device shownand described while remaining within the spirit and scope of my invention and l desire that all such modications shall be included in the appended claims. i claim as my invention: l. A controller assembly for mounting on an appliance to govern an operation of an element of said appliance, said assembly comprising a power driven timer structure, a single standard of non-circular cross-sectional shape mounted on and supported solely by said timer structure at one side thereof, an element of said appliance supported solely by said assembly, movable be- 5 tween two opposed limit positions and biased to one of said positions, said element having a por- `tion mounted on the standard and guided solely thereby in its reciprocal movements, a detent on the assembly for holding said element in its other limit position and an actuator movably mounted on' and supported solely by said standard and arranged to operatively engage said element to move it against said bias to its other llimit. position and into operative engagement with said detent, said actuator being effective during said movement to energize said power driven timer and being returnable to its initial position by the timer vand effective during its return movement to cause release of said detent. 2. A mechanical timer assembly for causing movement of an element 'after a time interval, said assembly including a frame, a spring, a single standard of non-circular cross-sectional shape supported by said frame at one side thereof, an element reciprocally movable on said standard n and supported and held in proper operative position solely by said standard, means supported solely by the frame for biasing said element to one limit position, a carriage slidable on said 'y standard and supported solely thereby adapted tion by said spring as it unwinds and a detent on the timer to hold said element in said other limit position, release of said element being effected by the action oi'- said carriage on said detent during return movement of said carriage. 1i l asomar 3. A timer as setv forth in claim 2 in which the cross sectional shape of said standard is other than circular to prevent lateral turning movement of said element thereon. 4. A unitary mechanical timer assembly for causing release of an element after a time interval, said assembly including a frame, a spring driven gear train therein, a single standard supported by said frame at one side thereof in substantially ilxed position relatively to the frame, said standard having a polygonal cross sectional area, an element reciprocally slidable on said standard supported solely thereby and prevented from turning movement relatively to the timer by inter-fitting engagement with said standard, a spring connected tosaid timer frame` and to said element for biasing the sameto a position at one end ofv its sliding movement, a detent, a carriage reciprocally slldable on said standard manually actuable to move said element in one direction into engagement with said detent and connected to simultaneously wind up the timer spring and movable in the opposite direction by the timer as the spring unwinds and causing the detent to release said element at substantially the end of its movement in the opposite direction. 5. A controller assembly as s et forth in claim 1 in which the cross sectional area of said standard is of polygonal shape and the contour of the element portion mounted on the standard is complementary thereto. 6. A timer assembly asset forth in claim 2 including a thermally-actuable element supported solely by said timer assembly for cooperating with said timer to vary the length of time during which said reciprocally movable element is held bythe detent, said length of time decreasing with -increase of temperature of the thermally-actuable element. ' ROBERT SARDESON.

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Cited By (4)

    Publication numberPublication dateAssigneeTitle
    US-2567075-ASeptember 04, 1951Emerson Electric Mfg CoElectric toaster
    US-2611849-ASeptember 23, 1952Chicago Electric Mfg CoToaster timer
    US-2637267-AMay 05, 1953Hoover CoElectric toaster
    US-2665629-AJanuary 12, 1954Frederick E HummelAutomatic toaster with thermostatic delay means