US3587025A

US3587025A - Thermostatic control for electric toaster

Info

Publication number: US3587025A
Application number: US4867A
Authority: US
Inventors: Sophocles J Dokos; Chester H Wickenberg; Charles E Swanson; Bernardas Gasparaitis
Original assignee: SUNBEAM
Current assignee: SUNBEAM
Priority date: 1970-01-22
Filing date: 1970-01-22
Publication date: 1971-06-22
Anticipated expiration: 1988-06-22

Abstract

A thermostatic control for an electric toaster having a frame and a movable heat-sensing element and a bracket which supports an adjustable means. A resilient arm portion of the bracket forms a stop which limits the movement of the element. A reset means is pivotally mounted to the bracket for repositioning the element to its sensing portion. In one embodiment, the adjustable means consists of a hollow shaft which has a spring that projects through the shaft and engages the element so as to move the element into its sensing position. The lower end of the spring is depressible into engagement with the element by means of a button.

Description

United States Patent Appl. No. Filed Patented Assignee THERMOSTATIC CONTROL FOR ELECTRIC TOASTER [50] FieldofSearch 337/ll3, 333, 334, 337, 338, 339, 342, 343, 345, 347, 340; ZOO/166.1

References Cited UNITED STATES PATENTS 3,515,856 6/1970 Dokos 2,543,036 2/l95l May Primary Examiner-Bernard A. Gilheany Assistant ExaminerDewitt M. Morgan Attorney-George R. Clark 337/345 (X) 200/l66(.l)

of the element. A reset -means is pivotally mounted to the bracket for repositioning the element to its sensing portion. In

10 chimsn Drawing Figs one embodiment, the adjustable means consists of a hollow US. Cl 337/333, shaft which has a spring that projects through the shaft and env 200/166 J gages the element so as to move the element into its sensing Int. Cl H016 37/04. position. The lower end of the spring is depressible into en- H0 1 h 37/20, HOlh 37/54 gagement with the element by means of a button.

a a, I I 35/ 1A as 52 W14? //.1ll llllll! g JZ 1 141; Z .570 5,04 9 a 11: 779 a 143 .112 J0 249 2 zazazrtn 316 x 23, 295

vfigf PM 294 195 790 PATENTED JUN22 |97| SHEET 2 BF 9 PATENTEU JUH22 I97! SHEET 3 OF 9 PATENTEU Juuzzmn 3,587,025

sum 7 or 9 TI'IERMOSTATIC CONTROL FOR ELECTRIC TOASTER BACKGROUND OF THE INVENTION This application is'a division of US. application Ser. No. 821,578, filed May 5, 1969, now U.S. Pat. No. 3,533,350 which is a division of US. application Ser. No. 668,597, filed Sept. 18, 1967, now US. Pat. No. 3,472,154, and is assigned to the same assignee as the instant invention.

One of the most popular electrical appliances found in the kitchen of a home today is the electric toaster. Because it is one of the most frequently used appliances in the kitchen, it normally remains plugged into an electrical outlet and is kept on the countertop instead of being stored with appliances that are now used frequently. Consequently, toasters must be attractively styled due to their continued exposure and use in the kitchen plus the unit should occupy as little of the working space of the kitchen counter as practical.

While four-slice toasters have gained in popularity, the most frequently sold toaster is still the two-slice unit wherein the bread slices are disposed in spaced parallel relationship necessitating a rather bulky, square housing which consumes considerable working space on the kitchen counter. However, the standard, square design allows considerable space within the toaster for the various components.

The working space of the counter can be conserved by having a longer and much narrower toaster which can fit along the rear edge of the counter which is not normally considered as usable working space. Such a configuration is possible if the toaster is provided with a long, narrow receiving slot for slices of bread which are inserted in an in-line relationship wherein the common edges of the bread are adjacent one another. Moreover, it is necessary for the toaster components to be arranged so that' very little width is required. Naturally, the toaster must function equally well or better than the standardshaped toaster where internal space is not a problem.

A desirable feature for a thin toaster is for the selectable control mechanism to be disposed on the side of the toaster shell since the toaster will normally be positioned on the kitchen counter with the relatively long side facing the user. Preferably, the control-actuating member or knob should be spaced in some manner from the toaster shell which can become hot during prolonged toaster usage.

In a thinly designed toaster, it is desirable to have as much operating mechanism disposed within the space provided for the toasting chamber as possible in order to permit the toaster to be as thin as practical. That is, the elevator assembly, including the bread carriage and the lifting means, should be located between the toasting heaters defining the toasting chamber. In addition, the power source for operating the elevator assembly should not be located outboard of the heater assembly.

In instances where space is an important consideration, the thermostatic control should be integrated with the switch assembly so that both may be assigned the same location. This design concept also lends itself to lower manufacturing costs. Naturally, the combined thermostatic control and switch assembly should use as few parts as possible and still accurately function, and the parts should be inexpensive to fabricate.

SUMMARY OF THE INVENTION The invention relates to an electric toaster having an outer shell with a long, narrow slot for receiving slices of bread in an in-line relationship. Disposed within the toaster shell is a narrow elongated toasting chamber located below the breadreceiving slot. An electrically insulating member is positioned at each end of the toasting chamber, and electrical resistance wire is wound therebetween to define two toasting heaters spaced on each side of the chamber. In order to support the bread within the toaster, there is provided an elevator assembly including a horizontally extending bread carriage and a lifting mechanism for moving the carriage between an upper bread-receiving and withdrawing position and a lower toasting position. Supplying power to the lifting mechanism is a thermal motor including the resistance wire and the insulating support members. In this arrangement, the resistance wire is tightly wound between the members, and the members are movably mounted so that current passing through the wire causes it to expand which, in turn, causes movement of the members. The motion of the thermal motor actuates the lifting mechanism.

Governing the operation of the toasting heaters is a thermostatic control and switch assembly which is mounted on and supported by the toaster shell. The thermostatic control has a trip finger extending into the toasting chamber and is disposed to be acted upon by a reset mechanism mounted on the bread carriage so that the insertion of a slice of bread into the toaster will actuate the toasting cycle, and at the completion of the cycle, the reset mechanism will reset the thermostatic control upon the removal of the toasted bread.

Other novel features of the toaster, as will become apparent from the more detailed description, are the improved means for pivotally mounting the crumb tray and the improved mounting of removable bread guides stamped from sheet metal material.

Accordingly, it is an object of the present invention to provide an improved electric toaster which is easily assembled and inexpensive to manufacture.

It is a further object of the present invention to provide an improved electric toaster arranged for receiving slices of bread in an in-line relationship with a toasting chamber defined by parallel spaced 'heaters supported by insulating members at each end of the elongated toasting chamber.

It is still a further object of the present invention to provide an electric toaster having improved means for pivotally mounting a crumb tray by utilizing the plastic molded end panels.

It is still another object of the present invention to provide an improved mounting of a thermostatic control to an outer shell of the toaster.

Yet another object of the present invention is to provide a toaster having an improved thermal motor for supplying power to move the bread carriage.

Another object of the present invention is to provide a toaster with an improved thermostatic control governing the toasting operation, and the control being inexpensively and easily manufactured.

Further objects and advantages of the present invention will become apparent as the following description proceeds, and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the present invention, reference may be had to the accompanying drawings in which:

FIG. 1 is a perspective view of an electric toaster embodying the present invention with a portion of the power cord broken away;

FIG. 2 is an end elevational sectional view taken substantially on line 2-2 of FIG. 1;

FIG. 3 is a side elevational sectional view taken substantially on line 3-3 of FIG. I with the power cord deleted;

FIG. 4 is an exploded assembly view of the subject toaster;

FIG. 5 is a perspective view of the thermal motor and elevator assembly with the reflector assembly partially shown;

FIG. 6 is an enlarged, fragmentary, side elevational sectional view taken substantially along line 6-6 of one of the components illustrated in FIG. 4 with the reflector assembly removed;

FIG. 7 is a fragmentary plan sectional view taken substantially on line 7-7 of FIG. 6 showing the electrical resistance wire partially broken away and the bread guides removed;

FIG. 8 is a fragmentary sectional view taken substantially on line 8-8 of FIG. 6 illustrating the reset mechanism with the link disposed alongside of the horizontally extending thermostatic control'trip lever and with the reset and trip spring removed;

FIG. 9 is similar to FIG. 8 but with the link positioned below the thermostatic control trip lever which is the normal position of the reset mechanism upon completion of the toasting cycle and after the bread carriage has risen to the upper withdrawing position but before the toast has been removed from the bread carriage;

FIG. 10 is an end elevational sectional view taken substantially on line 10-10 ofFIG. 6;

FIG. 11 is a fragmentary elevational view taken substantially on line 11-11 of FIG. 7 illustrating the mounting of the thermostatic control and switch assembly to the toaster shell;

FIG. 12 is a fragmentary plan sectional view taken substantially on line 12-12 of FIG. 11;

FIG. 13 is a fragmentary sectional view taken substantially along line 13-13 of FIG. 11;

FIG. 14 is a fragmentary sectional view taken on line 14-14 of FIG. 12;

FIG. 15 is a fragmentary sectional view taken substantially on line 15-15 ofFIG. 12;

FIG. 16 is a fragmentary sectional view taken substantially on line 16-16 ofFIG. 12;

FIG. 17 is a fragmentary sectional view similar to FIG. 12 but illustrating another embodiment of the thermostatic control and switch assembly;

FIGS. 18 and 19 are top plan views of the movable and stationary switch contact blades, respectively;

FIGS. 20 and 21 are a front and side elevational view, respectively, of one bread guide; and

FIG. 22 is a fragmentary elevational view of the upper portion of the right electrical insulating member without the resistance wire and terminals assembled thereto.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, there is illustrated a new and improved electric toaster constructed in accordance with the features of the present invention and referred to generally by the reference numeral 30. This toaster includes an outer enclosure or housing defined by a pair of

opposite end panels

32 and 33, an outer shell 34 of U-shaped cross section and a base 38. The shell 34 comprises a top wall and two

sidewalls

41 and 42.

The top shell wall 40 is provided with an elongated breadreceiving slot 43 defined, in part, by downwardly

bent flanges

44 and 45 and forming an entrance to bread-toasting chamber 47 which is relatively long and narrow and located beneath the slot. Mounted on side shell wall 41 is control housing 50 bearing printed indicia 51, and there is disposed on said housing, a color control knob 52 having a pointing dot 53 thereon so that the user may selectively rotate the knob in order to obtain a given degree of toasting. Enclosed within the control housing 50 and mounted on and supported by side shell wall 41 is a thermostatic control and switch assembly 55 described hereinafter in detail. The bottom edges of shell sidewalls 41 and 42 are bent inwardly to form longitudinally extending flanges 57 and 58 for adding rigidity to the shell and for mounting purposes. Each of the shell flanges 57 and 58 are formed with suitable mounting holes 59.

The

end panels

32 and 33 are preferably constructed of molded plastic material such as phenolic resin or the like and are provided with lower depending portions 61 and 62, respectively, defining legs for supporting the toaster on a table or kitchen counter top. The outer faces of

end panels

32 and 33 may be provided with integrally molded features such as projecting

flanges

64 and 65 to serve as heat-insulated handles for transporting the toaster 30. Moreover, each

end panel

32 and 33 is integrally formed with a notched periphery or edge 67 and 68 adapted to be inserted inside of the outer shell 34 at its ends which are slightly bent inwardly with an inwardly extending

U-shaped rib

70 and 71 which are adapted to cooperate with clips 73.welded to a depending flap 74 of shell top wall 40 adjacent the ends of slot 43 for securely holding the end panels to the shelland with inwardly extending

floor portions

75 and 76 having vertical holes 78 which, when the end panels are assembled to the shell, are in alignment with shell flange holes 59. For a purpose to be discussed hereinafter,

end panels

32 and 33 are molded with opposed horizontally extending

recesses

80 and 81, respectively, in the

floor portions

75 and 76.

Positioned at the bottom of toaster 30 is base 38 having raised

end portions

83 and 84, each of which has a plurality of mounting holes 85. When the shell 34,

end panels

32 and 33 and base 38 are in assembled relationship, the

base end portions

83 and 84 rest on the end

panel floor portions

75 and 76, and a plurality of threaded fastening members 87 pass through the shell mounting holes 59, end panel floor portion holes 78 and base end portion holes whereby the assemblage is rigidly held together with the use of a minimum number of fasteners and, consequently, it may be readily disassembled. For providing power to the toaster 30, an electrical cord 88 enters into and is locked to end panel 33.

Preferably, base 38 is fabricated integrally from sheet metal material and includes longitudinally extending

side runners

91 and 92 which are adapted when assembled within the toaster to rest on shell flanges 57 and 58, respectively, as can be seen in FIGS. 4, 5 and 10. The base 38 is formed with upturned flanges 94 and 95 running longitudinally and defining an elongated opening 96 w'hichis in vertical alignment with toasting chamber 47 and shell bread-receiving slot 43. Along base flanges 94 and 95 are a plurality of pairs of abutments, each of which consists of an

abutment flap

97 and 98. The abutment flaps are bent inwardly towards opening 96 and are formed so that the points of flaps 97 are facing in the opposite direction from the points of flaps 98. Also formed in base 38 are a plurality of locking slots 99 and oval shaped projections 100. Lastly, the base 38 is stamped with a hole 102 extending transversely through both base flanges 94 and 95 and crumb tray locking openings 103 located in the base flanges 94 and 95.

For the purpose of mounting a heater assembly within the toaster 30, four truss springs 105, preferably formed from resilient material, are riveted to the base 38 by rivets 106 so that the free ends 112 thereof are slightly upwardly inclined. Each of the truss springs 105 is formed with an oval opening 108 into which the oval-shaped base projections extend in order that the truss springs may be properly oriented. Therefore, four truss springs are rigidly held to base 38 with their free ends 112 extending toward the opposite ends of the base as may be seen in FIG. 6. Moreover, the truss spring 105 is formed with upturned edges 109 on each side thereof adjacent to rivet 106, and spaced therefrom are upturned edges 110 which stop short of free end 112. Obviously, those portions of the truss spring having upturned edges are more rigid than those portions without the upturned edges. Consequently, if a bending moment is imposed on truss spring 105, the portions between

upturned edges

109 and 110 would do the majority of the bending and may be considered as pivot areas 113.

Located near each end of the toasting chamber 47 and partially supported by truss springs 105 are vertically extending electrically insulating members and 116, both of which are preferably fabricated from a ceramic material such as alumina. Near the bottom of insulating

members

115 and 116 are formed relatively large recesses 118 into which truss spring ends 112 extend with considerable clearance so that the spring ends can pivot within the recesses to define a pivotal connection 114. Vertically spaced along the sides of insulating

members

115 and 116 are a plurality of L-shaped ears 120 which are relatively thick and have their free leg 121 facing away from the toasting chamber 47 and the other leg 122 joining to the insulating members. The end portion of each leg 121 and the outer portion of leg 122 are rounded. As can be seen in FIG. 22, insulating member 116 is formed with a starting slot 123 along one edge near the top and a finishing slot 124 along the opposite side thereof near the top. Adjacent to

slots

123 and 124 are locking cavities 125 having a circular shape with opposed extending slot portions 126. For the purpose of increasing the structural integrity of the insulating

members

115 and 116, each has a strengthening rib 128 on the surface facing away from the toasting chamber 47. Near the top of each insulating member are formed a pair of relatively large supporting recesses 130.

Assisting in holding the insulating

members

115 and 116 in their proper position is upper truss assembly 132 including two oppositely disposed

identical trusses

133 and 134 and a T- shaped crosspiece 135 which is rigidly attached to

trusses

133 and 134 by staking and welding. Each

truss

133 and 134 has an L-shaped cross section and is formed with a plurality of oval-shaped projections 137 which are identical to projections 100 on base 38 and downwardly angled limiting flaps 138 located at each end thereof for preventing the truss assembly 132 from ever springing downwardly over center. Two truss springs 105 are riveted to each

truss

133 and 134 by rivets 106 whereby the truss spring free ends 112 extend outwardly away from toasting chamber 47 and into insulating member upper recesses 130 with considerable clearance to define pivotal connection 114. As may be seen in FIGS. 3, 5 and 6, the truss springs 105 acting upon insulating

members

115 and 116 tend to bias the upper truss assembly 132 downwardly and the insulating members outwardly away from the toasting chamber 47.

In order to restrain and bias the insulating

member

115 and 116 inwardly towards toasting chamber 47 and to constitute heaters for accomplishing the toasting operation, electric resistance wire 140 is looped back and forth between insulating

member

115 and 116 passing around insulating member ear legs 122 so that the wire convolutions formed running between common sides or opposed edges of the insulating members constitute a first heater 142 lying in a substantially vertical plane and adjacent to one side of the elongated toasting chamber 47. The resistance wire 140 upon reaching the bottom of insulating member 115 is fed along a slot 144 formed in said member and extends across the backed face thereof whereupon it is looped back and forth between the opposite common sides or opposed edges of the insulating mem- 116 towards each other and thereby causing the upper truss assembly 132 to move upwardly. It should also be appreciated from the discussion concerning the truss spring 105 that the pivotal movement of truss springs 105 allowing the insulating

members

115 and 116 to move outwardly and inwardly takes place mostly at truss spring

pivotal areas

113 and 114. Consequently, truss springs 105 not only act as pivotal linkage, but also biases the insulating members outwardly.

in order to support and transport slices of bread within the toaster 30, there is provided an elevator assembly 155 including a bread carriage 156 which is disposed for vertical movement in the toasting chamber 47 between first heater 142 and second heater 146. At the start of a toasting cycle, the bread carriage 156 is at an upper bread-receiving and withdrawing position as illustrated in H68. 3 and 6. The bread carriage is capable of vertical movement and can move to a lower or toasting position which is illustrated in broken lines in FIG. 6. in the lower position, the bread supported on carriage 156 is disposed between

heaters

142 and 146 for toasting. When the bread carriage 156 returns to the upper position, the slices of bread project a sufficient distance through shell bread slot 43 so that the user may conveniently withdraw the toasted bread from the toaster 30. Preferably, the bread carriage 156 is formed from sheet material and is sufficiently long to span most of the distance between the insulating

members

115 and 116. In order to support slices of bread on the bread carriage 156, it is formed with a plurality of transversely extending finbers and 116 to form a plurality of convolutions which constitute a second heater 146 which is spaced and parallel to the first heater 142 with the toasting chamber 47 located therebetween. Each heater has the wire convolutions spaced closer together near the bottom in order to uniformly toast bread. The resistance wire 140 is tightly wound when at room temperature between the insulating

members

115 and 116 in such a manner as to bias the insulating members inwardly and thereby subject the truss springs 105 to stress so that the truss springs 105 are working against the tension of resistance wire 140. Inasmuch as the resistance wire 140 is under considerable tension, one end of the resistance wire is welded to a spade-shaped terminal 148 which is securely locked into cavity by the edges of the terminal engaging into the slot portions 126 so that the wire at this end passes through starting slot 123. correspondingly, the opposite end of resistance wire is rigidly held. to insulating member 116 and the wire is positioned in finishing slot'124 by this end being welded to spade-shaped terminal 149 which extends into locking cavity 125 with the edges thereof nested into slot portions 126.

It should be appreciated that the first heater 142 and the second heater 146 are designed in such a manner as to be a part of a thermal motor 150 consisting of the base 38, insulating

members

115 and 116, upper truss assembly 132 and resistance wire 140. The thermal motor 150 is designed so that the upper truss assembly 132 is capable of vertical movement. When an electrical potential is imposed across

terminals

148 and 149, the current passing through resistance wire 140 causes it to lengthen due to thermal expansion, and the truss springs 105 bias the upper truss assembly 132 downwardly towards base 38. Similarly, when the electrical potential is removed from

terminals

148 and 149, the resistance wire 140 cools and contracts pulling the insulating members 115 and gers 157. Guiding the vertical movement of bread carriage 156 is bearing 159 which is mounted to the carriage at its approximate midpoint and extends through a square carriage opening 160. Preferably, the bearing 159 is fabricated from a material which is not adversely effected by high temperature and is relatively smooth such as a glass-filled TEFLON insulator material. Bearing 159 has a large diameter 161 at one end and a smaller diameter end 162 which extends through the bread carriage opening 160. Securing the bearing 159 to the bread carriage 156 is a spring retainer 163 which is in locking engagement with the small diameter end 162. Both ends of bearing 159 are formed with a vertically extending slot 165 as may be seen in FIG. 7. immediately below bearing 159, the bread carriage 156 has a cutout portion 166 which provides clearance permitting the bread carriage to be lowered to the toasting position. Pivotally secured to each end of bread carriage 156 by means of shoulder rivets 169 are tie bars 167 which are oppositely oriented so that they are secured to opposite sides of the bread carriage. Limiting the pivotal movement of tie bars 167 are laterally extending abutments170 which are integrally formed with the bread carriage. Consequently, the tie bars 167 may freely rotate towards the ends of the bread carriage 156 but are permitted limited rotational movement toward the center due to abutments 170. Pivotally connected to each tie bar 167 is a J-shaped lifter arm 172 by means of shoulder rivets 174. The hook ends 175 of lifter arms 172 are formed with in-line openings 176 through which an axle 177 extends and also passes through base flange holes 102. In this manner, lifter arms 172 are pivotally connected to the base 38 at approximately the midpoint of toaster chamber 47. Tie bars 167 and lifter arms 172 constitute a linkage assembly 179 which connects the bread carriage 156 to the base 38. Therefore, the linkage assembly 179 supports the bread carriage 156 permitting it to move from the upper breadreeeiving position to the lower toasting position by the lifter arms 172 pivoting downwardly while the tie bars 167 pivot outwardly. As may be seen in FIG. 6, the bread carriage 156 when in the lower position receives axle 177 in the cutout portion 166 whereby the bread carriage is permitted considerable vertical movement within a rather limited space. Furthermore, it should be appreciated that the bread carriage 156 and the linkage assembly 179 are essentially disposed within the confines of the toasting chamber 47 thereby allowing the toaster to be relatively thin. it should be apparent that the bread carriage abutment 170 prevents the tie bars 167 from ever rotating inwardly so that the lifter arms 172 would pivot upwardly against the bread carriage fingers 157. Thus, the linkage 179 can never be swung past the abutment 170 causing the linkage assembly to be inoperative.

As may be seen in FIGS. 6 and 7, the lifter arm hook end 175 includes short leg 181 which is recessed inwardly and contains a downwardly bent projection 182. Naturally, if a vertical force were exerted upon the downwardly bent portion 182, the linkage assembly 179 would cause the bread carriage 156 to move downwardly. Moreover, since the downwardly bent portion 182 isfar closer to axle 177 on which lifter arm 172 rotates than the distance between the axle and the connection of the lifter arm 172 to the tie bar 176, a very small vertical movement of projection 182 causes a far greater vertical movement of the bread carriage. I

Providing power transmission between thermal motor 150 and linkage assembly 179 is a driver assembly generally referred to byreference numeral 185 which extends vertically through the center of the toasting chamber 47 from the upper.

truss assembly 132 to the linkage assembly. As indicated hereinbefore, the upper truss assembly 132 includes a T- shaped crosspiece 135 which is securely attached to

trusses

133 and 134. The crosspiece 135, as may be seen in FIG. 10, includes an upper horizontal leg 187, the ends of which are securely attached to.

trusses

133 and 134. Along the upper edge of leg'187 are spaced two circularprojections 188. Extending downwardly from the upper horizontal leg 187 is a vertical leg 190 having a semicircular groove 191 extending vertically from between circular projections 188, a notched portion 192 located at the bottom end of vertical groove 191 and two spaced vertically extending slots 193, one of which is disposed on each side of the vertical groove 191.

Cooperating with and secured to crosspiece 135 is a vertically extending driver 195 having an upper portion 196, and recessed therefrom at shoulder 197 are

two'spaced legs

198 and 199. As ma'ysbe conveniently seen in FIGS. and 10, the driver upper portion 196 includes a vertically extending groove 202 having formed on its concave surface threads 203, a pair of laterally extending projections 205 which extend through crosspiece slots 193 and are bent over locking the driver 195 in vertical sliding relationship with crosspiece 135 and a rectangular opening 207. When the driver 195 is assembled to the crosspiece 135, the crosspiece vertical groove 191 and the driver vertical groove 202 cooperate to define a vertically extending circular opening through which tension adjustment screw 209 is positioned. As may be seen in FIG. 10, the adjustment screw 209 has an enlarged upper head 210 disposed between crosspiececircular projections 188 and an enlarged lower head 211 positioned in crosspiece notched portion 192 and also disposed within driver rectangular opening 207. To facilitate the rotational movement of adjustment screw 209, enlarged upper head 210 is fabricated with a driving socket opening 212. As is evident from the relationship between the crosspiece 135, the driver assembly including driver 195 and threaded adjustment screw 209, the rotation of the adjustment screw changesthe relative vertical relationship between the upper truss assembly 132 and the driver 195. That is to say, if the upper truss assembly 132 were to remain stationary, the rotation of adjustment screw 209 in one direction lowers the driver 195 while the rotation in the opposite direction would raise the driver 195 inasmuch as the enlarged heads at the ends of the adjustment-screw prevent the screw from moving in a vertical direction with respect to crosspiece 135, and the threads on the adjustment screw engage with the driver threads 203 causing movement of the driver.

To relate the vertical movement of upper truss assembly 132 to the linkage mechanism 179, the

driver legs

198 and 199 each have a bent flange portion 215 extending parallel to the elongated toasting chamber 47, and these portions each have an outwardly bent tab 216 containing a driving notch 217 adapted to receive the lifter arm bent projection 182. As can best be seen in FIGS. 6 and 10, the downward movement of driver 195 exerts a downward force on lifter arm bent portion 182 causing the lifter arm to pivot downwardly and thereby causing the bread carriage .156 to move downwardly. In order that the bread carriage 156 will always be properly positioned horizontally, the bearing 159 is disposed between the

driver legs

198 and 199 whereby the bearing slots 165 are in operative sliding engagement with the legs. Therefore, the bearing 159 prevents longitudinal and transverse movement of the bread carriage. Moreover, it should be appreciated that a high multiplication of the downward movement of the upper truss assembly 132 is obtained by the linkage assembly 179 being pivotally connected to the-ends of the bread carriage 156. An additional benefit of attaching the linkage assembly 179 to the ends of the bread carriage 156 is that this relationship also tends to maintain the bread carriage in a level or horizontal position.

From the description, it should be apparent that the thermal motor 150 supplies the power through driver assembly 185 for actuating the bread carriage 156 by means of the linkage assembly 179. At the start of a toasting cycle, the bread carriage 156 is at the upper bread-receiving position. Upon energizing the

toaster heaters

142 and 146, the resistance wire 140 expands allowing the truss springs to move the insulating members and 116 outwardly and causing the upper truss assembly to move downwardly. The downward motion of the truss assembly is transmitted through the driver assembly 185 at its connection with the linkage assembly for causing the bread carriage 156 to assume the lower toasting position. After the completion of the toasting cycle, the heaters are deenergized, and consequently, the resistance wire contracts drawing the insulating members inwardly forcing the upper truss assembly and the driver assembly to move upwardly which, in turn, causes the bread carriage to move upwardly due to upwardly movement of the driver assembly and the pivotal movement of the linkage assembly 179. The adjustment screw 209 can be used to change the vertical location of driver 195 to change the tension in the resistance wire 140. Inasmuch as the driver assembly, the elevator assembly and the linkage'assembly are disposed essentially within the toasting chamber 47, the toaster shell 34 may be made exceedingly thin.

The preferred embodiment of the applicants toaster illustrated in the drawings is fully automatic whereby the user merely has to insert a slice of bread into the toaster shell slot 45 and rest the bread upon the carriage 156, and the toaster automatically lowers the bread to the toasting position, toasts the bread and thereafter raises the bread to the upper withdrawing position. The toasting of the slice of bread is controlled by the thermostatic control and switch assembly 55. With this construction, it is necessary that means be provided for actuating the thermostatic control and switch assembly 55 upon the insertion of a slice of bread onto carriage 156, and the withdrawal of the bread from the carriage causes the thermostatic control and switch assembly to be reset. In order to accomplish this objective, there is provided a reset and trip mechanism 220 mounted to the bread carriage 156. As may be seen in FIG. 6, the reset and trip mechanism 220 includes a trigger 222 pivotally mounted to the bread carriage by shoulder rivet 223, tension spring 225 attached at one end to an integral tab 226 including a spring receiving notch 227 struck from the bread carriage 156 and a link 230 which inter connects the trigger 222 and tension spring 225. The trigger 222 is disposed in the toasting chamber 47 so as to be engageable with a slice of bread insertedinto the half of the toasting chamber disposed between the driver and insulator 116. When there is no bread positioned on the carriage 156, the

trigger 222 is biased upwardly by tension spring 225 so that it assumes the position illustrated in FIG. 6. The trigger 222 includes arm portion 232 which is adapted to be engaged by bread inserted into the toasting chamber, a central portion 233 through which rivet 223 pivotally supports the trigger and an offset end portion 234 containing an opening 235 therein. Limiting the pivotalmovement of trigger 222 is tab 237 struck from the bread carriage 156. Link 230 is held to the bread carriage 156 byltab 238 struck therefrom and containing an opening 239 through which a link center portion 240 extends whereby the link may move longitudinally with respect to bread carriage 156 and may also pivot about the tab opening 239. To limit the pivotal movement of the link, the link center portion 240 is formed with a V-shaped extension 242 disposed to abut against the bread carriage 156. Before attaching spring 225 to the tab receiving notch 227, the spring is rotated sufficiently so that after assembly, it will exert a torsional force biasing the link 230 to pivot the link extension 242 against the bread carriage. The link 230 includes a bent end 244 adapted to pass through trigger opening 235 so that the trigger 222 and the link 230 are connected together and the opening 235 is sufiiciently larger than the portion of bent end 244 extending therethrough to permit the linkto pivot without binding with the trigger. In addition, the link 230 has a U-shaped section 245 to which extension spring 225 is attached and an actuator end 247 having an angular portion- 248 extending upwardly parallel to bread carriage 156 and outwardly from the bread carriage, an outer upright portion 250 and a horizontal portion 251 which extends parallel to the longitudinal direction of the bread carriage and back towards the spring 225.

In discussing the operation of reset and trip mechanism 220, it is necessary to understand that thethermostatic control and switch assembly 55 contains a trip lever 255 extending horizontally into the toasting chamber as disclosed in FIG. 7. When viewing the trip lever 255, it should be realized that when it is pivoted as seen in FIG. 7 towards insulator 115 that it closes a switch to energize the

heaters

142 and 146. In addition, the pivoting of lever 255 towards insulator 115 resets the thermostatic control so that it is disposed to sense the surface temperature of the bread being toasted. Without a slice of bread on carriage 156, the reset and trip mechanism and thermostatic control trip lever are as illustrated in FIG. 8. In operation, the insertion of a slice of bread on top of trigger 222 causes it to pivot downwardly and thereby slides link 230 towards trip lever 255 until the link outer upright portion 250 pivots it sufficiently to reset the thermostat and close the switch. As indicated previously, once the heaters are energized, the bread carriage is lowered to the toasting position. After the toast has reached a desired color, the thermostat opens the electrical circuit causing the thermal motor 150 to raise the bread carriage to the bread withdrawal position. Since the slice of bread is still on top of the trigger 222 when the bread carriage moves to the upper position, the link is still in a position to engage trip lever 255. Inasmuch as the link comes up underneath the trip lever 255, thelink horizontal portion 251 strikes against the trip lever 255 causing the link to rotate downwardly as indicated in H0. 9. As soon as the bread is removed from the bread carriage, the tension spring 225 biases the trigger 222 upwardly forcing link 230 to slide towards insulator 116. As soon as the link horizontal portion 251 clears the trip lever 255, the tension spring 225, due to its torsional preloading, rotates the link until the link V-shaped extension 242 abuts against the bread carriage 156. Thus, the outer upright portion 250 of the link 230 is once again in alignment, as shown in FIG. 8, to actuate the trip lever 255 upon the insertion of another slice of bread. It should be appreciated that the reset and trip mechanism is very simply constructed and operated. The mechanism is inexpensively manufactured since it consists of four basic parts, namely, trigger 222, link 230, shoulder rivet 223 and a simple tensionspring 225. Of these parts, the trigger 222 is inexpensively formed from sheet material, and the link 230 is inexpensively processed from coiled wire.

Controlling the operation of the toasting cycle is the thermostatic control and switch assembly 55 which is mounted to the toaster outer shell sidewall 41. As may be seen in FIG. 4, the side shell wall 41 is formed with a depressed area 260 including an elongated opening 261 extending horizontally. The depressed area 260 also includes a raised mounting area 262 positioned at one side of the opening 261 and another raised mounting area 263 disposed at the opposite end of the opening 261. Mounting area 262 contains a hole 265 while the mounting area 263 has a horizontally extending slot 266. On each side of mounting area 263 is a relatively small locking hole 267. The thermostatic control and switch assembly 55 includes a rigid, relatively thick, channel-shaped frame 269 which is preferably fabricated from a material which readily conducts heat such as aluminum The elongated frame 269 has an elongates hole 271 located near one end and at the other end, has a rectangularly shaped projection 273. As may be seen in FIG. 11, the thermostatic control and switch assembly 55 is horizontally disposed in the shell side opening 261 with the frame elongated hole 271 in alignment with mounting area hole 265 while the frame rectangularly shaped projection 273 is disposed within the mounting area slot 266. A thread-cutting screw 275 passes through frame elongated hole 271 and into threaded engagement with mounting area hole 265 thereby locking one end of the frame rigidly to mounting area 262. lt should be appreciated that the elongated frame opening 271 permits a variation in the horizontal locking position of the frame 269 to compensate for assembly tolerances. At the other end of frame 269 as shown in FIG. 4, the rectangularly shaped projection 273 is locked into slot 266 by means of a resilient U-shaped mounting clip 277 having a central cross portion 278 and two U-shaped spaced legs 279 formed with an inwardly pointing barb 280. Once the frame 269 has been placed in its proper position so that the frame projection 273 is in slot 266, the U-shaped mounting clip 277 can easily be inserted so that the frame is disposed between the two legs 279 and the clip pushed to its locking position so that the legs are clamped against the depressed area 260 adjacent to the mounting area 263 whereby the barbs 280 are snapped into engagement with locking holes 267. Thus, with this single mounting clip, one end of frame 269 is securely mounted to area 263. However, it should be appreciated that the resilient mounting clip 277 does not prevent the frame projection 273 from moving longitudinally within slot 266. In addition, both the thread-cutting screw 275 and the clip 277 urge the frame 269 into intimate heat-transmitting relationship with the shell wall 41. During the toasting operation, the outer shell 34remains relatively cool with respect to the internal components, and consequently, the heat which is transferred to the frame 269 may be dissipated to the shell 34 in order to maintain the frame 269 at a relatively cool temperature. In this manner, the outer shell 34 can be considered to be a cold sink for the thermostatic control and switch assembly 55. The mounting of the thermostatic control and switch assembly 55 to the outer shell 34 is accomplished in such manner to compensate for the difference in thermal expansion of the frame 269 and the outer shell 34. Preferably, the outer shell 34 is fabricated from sheet steel and thereafter plated. Considering that the outer shell 34 remains at a cooler temperature during the toasting cycle than frame 269 and that the frame has a higher coefficient of thermal expansion than the shell, the present mounting arrangement allows the frame to expand at a faster rate than the shell so that no stresses are imposed on the thermostatic control and switch assembly 55. That is to say, as the frame 269 expands at a faster rate than the shell 34, the rectangularly shaped projection 273 is permitted to slide in slot 266 inasmuch as the other end of the frame is fixedly attached to the shell by means of screw 27S. Correspondingly, as the frame 269 cools, the frame again is permitted to move with respect to the shell 34.

At this juncture, the operation and structure of thermostatic control and switch assembly 55 will be examined. The thermostatic control and switch assembly 55 includes a switch assembly 285 and a thermostatic control 286. As indicated hereinabove, the thermostatic control 286 has an elongated channel-shaped frame 269, and disposed therein is an elongated bimetallic heat-responsive element 288 which is rigidly attached near its ends to a bight portion 290 of frame 269 by means of two spaced square-headed rivets 292. The heatresponsive element 288 is provided with a central portion 294 disposed between two V-shaped portions 295. The operation of this type of a heat-responsive element is well known in the art, and the theory of operation will not be discussed herein. Suffice it to say that the heat-responsive element 288 has a heat-sensing position which is indicated in broken lines in FIG. 12 and an inactive position illustrated in solid lines in FIG. 12. When the heat-responsive element reaches a determined temperature, it snaps inwardly toward the frame bight portion 290. The frame 269 is formed with two spaced upright flange portions 297 which extend longitudinally adding rigidity to the frame and shielding the heat-responsive element from side radiant energy along with increasing the mass of the frame to increase its effectiveness as a cold sink. Two integral locking lugs 301 and 302 are bent upwardly from the frame bight portion 290.

A multipurpose mounting bracket 305 is a unitary piece formed by stamping from sheet metal and is mounted to the back side of frame bight portion 290 by lug 302 projecting through an opening 306 having four locking fingers 307 spaced at right angles for preventing motion in any direction and lug 301 projecting through opening 308 having oppositely disposed, transversely extending locking' fingers 309 for preventing transverse movement. The mounting bracket 305 comprises generally a first horizontal portion 312 which contains hole 306, a first upright portion 313, a second horizontal portion 314 which is spaced above the first horizontal portion 313, a second upright portion 315 which is parallel to the first upright portion 313 and a third horizontal portion 316 which is held firmly against the frame bight portion 290 by locking fingers 309 locking into lug 301. The first horizontal mounting bracket portion 312 includes a resilient arm 319 with a downwardly turned- L-shaped extension'320 being provided with a finger 321 extending transversely to frame 269. As may be seen in FIGS. 12 and 16, the frame bight portion 290 has a central opening 323 through which the extension 320 projects, and that finger 321 is disposed to limit the outward movement of heat-responsive element 288. Thus, the location of finger 321 determines the temperature at which the heatresponsive element 288 snaps inwardly against the frame bight portion 290. That is to say, if the finger 321 were to move away from the frame bight portion 290, the element 288 would have to reach a higher temperature before it would snap inwardly. Correspondingly, if finger 321 were moved closer towards the frame bight portion 290, a lower temperature is required to snap the element 288 inwardly. Consequently, the location of finger 321 determines the setting of the thermostatic control 386. Formed on mounting bracket arm 319 is an annular, upwardly inclined rim 335 surrounding opening 336. The horizontal portion 312 also includes two spaced resilient ears 238 which pivotally support trip lever 255 which extends horizontally inwardly into toasting chamber 47. The trip lever 255 is bent so that end 340 extends through frame bight portion hole 323 to a point adjacent to heat-responsive element 288. When the trip lever 255 is pivoted in a counterclockwise direction as viewed in FIG. 12, end 340 will snap the heat-responsive element 288 from its inactive position along frame bight portion 290 to a heat-sensing position indicated in broken lines. As discussed hereinbefore,

the reset and trip mechanism 220 on bread carriage 156 'is designed to pivot trip lever 255 upon the insertion of a slice of bread onto the bread carriage.

The primary purpose of first upright portion 313 and second upright portion 315 is to space the second horizontal portion 314 away from the frame 269. The second horizontal mounting bracket portion 314 has upturned edges 341 for increasing the rigidity thereof and a rectangular opening immediately above the resilient fingers 307 so that a tool may be inserted into said opening for firmly attaching the resilient fingers 307 to mounting lug 302. In addition, the second horizontal portion 314 contains an upwardly formed projection 342 and a thread 343 for receiving an adjustment shaft 345 having a threaded portion 346 and a reduced diameter portion 347 defining a shoulder 348 which abuts against upwardly inclined annular rim 335. With this construction, the rotation of adjustment shaft 345 causes a displacement of arm 319 which, in turn, changes the location of finger 321 governing the temperature at which the snap-acting heat-responsive element 288 snaps against the frame bight portion 290. Consequently, the rotation of adjustment shaft 345 varies the color setting of the thermostatic control.

In accordance with the present design, adjustment shaft 345 has an enlarged annular ring 350 provided with longitudinally extending serrations or teeth 35] and an outer shaft portion 353 carrying a split retaining ring 354. Secured to the adjustment shaft 345 is control knob 52 which is disposed for gripping by the user so that the adjustment shaft can be rotated providing a selection of color settings. The knob 52 includes a central bore 357 having an internal annular recess 358 into which retaining ring 354 is received to releasably hold knob 52 to adjustment shaft 345. Along central bore 357 is an enlarged annular surface 360 containing a plurality of serrations or teeth 361 complementary to shaft teeth 351. The meshing of teeth 361 with teeth 351 securely locks the knob 52 to the adjustment shaft 345 to prevent any angular displacement therebetween. If itis desired to change the angular relationship between the knob'and shaft, the knob can be moved outwardly until the teeth are disengaged whereupon the knob may be angularly displaced and once again snapped onto the shaft. In this manner, the thermostat can be properly set in order to have a proper correlation between indicia 51 and knob dot 53. The adjustment shaft 345 extends through control housing 50 by means of an elongated slot 363 being formed therein. The gap, between the adjustment shaft 345 and the control housing elongated opening 363 is necessarily rather large in order to accommodate an accumulation of assembly tolerances. However, it is desirable to prevent air entering into the control housing through opening 363 so that drafts will not effect the accuracy of thermostatic control 286. To establish a relatively airtight seal at opening 363, a sheet metal plate 365 is provided with an opening 366 through which the adjustment shaft threaded portion 346 passes with a minimum of clearance. A slot opening 367 is struck in plate 365 and receives mounting bracket upright projection 342 to prevent rotation of the plate. A weak compression spring 369 surrounds the adjustment shaft threaded portion 346 and biases the plate 365 against control housing 50 to effect an air seal at the juncture of adjustment shaft 345 and housing opening 363.

For mounting switch assembly 285 to frame 269, mounting bracket third horizontal portion 316 which is secured to the bight frame portion 290 by resilient fingers 309 locking to lug 301 is formed with laterally extending opposed lugs 372 and with an integral resilient finger 371 angled upwardly and inwardly toward adjustment screw 345. Two spaced elongated openings 373 are formed at the juncture of the frame bight portion 290 and the frame flange portions 297 for properly locating the switch assembly 285. As can be seen in FIGS. 11, 12, 13 and 14, switch assembly 285 includes a mounting insulator 375 preferably fabricated from ceramic material and defining a front face 374 and rear face 376. The insulator 375 has a central cutout portion 377, two opposed inwardly extending projections 378 and, immediately thereabove, a transversely extending slot 379 into which extends the third horizontal mounting bracket portion 316 so that the resilient finger 371 biases with sufficient force against slot 379 to firmly secure it to the mounting bracket. The depth of penetration of the portion 316 in slot 379 is limited by lugs 372 abutting against front face 374 to facilitate the subassembly of these two parts. To assist in locking and locating the switch mounting insulator 375 to frame 269, the switch mounting insulator projections 378 are received and nested into frame slot openings 373. With this construction, the mounting insulator 375 is held against frame 269, and the interlocking of projections 378 and the slot openings 373 prevents longitudinal movement and accurately positions the mounting insulator with respect to the frame. Equally spaced on each side of insulator cutout 377 are outer channels 381 and inner channels 382, all of which are parallel, have a rectangular cross section and are formed with a recessed or shoulder portion 383 adjacent to the switch mounting insulator rear face 376.

Extending through the channels 381 are a pair of movable contact blades 385 preferably fabricated from resilient sheet metal material. As can be seen in FIGS. 13 and 18, each movable contact blade has a terminal mounting portion 387 which extends beyond the mounting insulator rear face 376, a locking portion 388 having upturned edges 389 which taper inwardly and a central downwardly angled locking tab 390 with its free end facing away from the terminal mounting por-' tion 387, a downwardly angled portion 391 having mounted near its remote end an electrical contact 392 and a pair of upwardly bent spaced fingers 393. In addition, between the locking portion 388 and the downwardly angled portion 391 is a notched portion 394. The contact blades 385 are locked to the switch-mounting insulator 375 by inserting terminalmounting portion 387 through the channels 381 until the locking tab 390 is in locking engagement with insulator recessed portion 383 and the notched portion 394 abuts against the insulator front face 374. The blades 385 are rigidly secured to the switch-mounting insulator 375 by the wedging action produced by the tapered upturned edges 389 being forced against the sidewalls of channel 381 until the locking tab 390 can be sprung downwardly into recessed portion 383. With this construction, no fastening pieces are necessary to hold the contact blades 385 to the switch mounting insulator 375. However, the movable contact blades may easily be removed from the mounting insulator by simply biasing the locking tab 390 upwardly and withdrawing the blade from the channel 381.

Substantially stationary contact blades 396 are formed somewhat similarly to movable contact blades 385 and include a terminal mounting portion 397, locking portion 398 having upturned tapered edges 399 and a bent locking tab 400, notched portion 401 and straight portion 402 having a longitudinally strengthening rib 403 and an electrical contact 404. A rigid connection between stationary contact blade 396 and insulator 375 is obtained by inserting the blade into inner channel 382 until the tapered uptumed'edges 399 abut against the sidewalls of the channel, locking tab 400 is biased downwardly into recess 383 and notched portion 401 strikes against the insulator front face 374. After the pair of movable contact blades 385 and stationary contact blades 396 have been assembled to the mounting insulator 375, the electrical contacts 392 are in vertical alignment with the electrical contacts 404.

Before inserting the movable contact blades 385 into the mounting insulator, an insulating actuator 407 having a central point 408 and a pair of end slots 409 is assembled thereto by the actuator being inserted within the pair of upwardly spaced fingers 393 so that the actuator end slots 409 receive the downwardly angled portion 391. Consequently, after the contact blades 385 are assembled to the mounting insulator 375, the insulated actuator 407 is locked to the upper blades without the benefit of additional fastening elements.

As may be seen in FIGS. 12 and 13, the switch assembly 285 is locked to frame 269 so that the actuator central point 408 extends downwardly through frame opening 323 and contacts heat-responsive element 388 when said element is inactively positioned as illustrated in FIG. 12 holding the electrical con tacts 392 out of engagement with the electrical contacts 404. Once the heat-responsive element 288 has moved to the heatsensing position as pictured in FIG. 13, the movable contact arms 385 bias downwardly making a good electrical connection between electrical contacts 392 and contacts 404, thereby closing the switch. Upon the return of heat-responsive element 288 to the inactive position, it engages the insulated actuator central point 408 causing the pair of contact blades 385 to swing upwardly a distance sufficient to break the electrical connections between the contacts 392 and the contacts 404. Therefore, it should be appreciated that the electrical switch assembly 285 is open whenever the heat-sensing element is in the inactive position and is closed whenever the heat-sensing element is in the sensing position.

The electrical circuit for toaster 30 is relatively simple. As can be seen in FIG. 4, a pairof electrically conducting insulated wires 412 lead from the cord 88 and are attached to the stationary contact blade terminal mounting portions 397 by any suitable means such as welding. Another pair of suitable electrical conducting insulated wires 413 are in good electrical attachment with the movable contact blade terminal mounting portions 387 and lead to and are attached to the

terminals

148 and 149 positioned at opposite ends of resistance wire 140. Therefore, when the switch assembly 285 is closed and the cord 88 is attached to a source of electrical power, an electrical potential is imposed on the resistance wire 140. However, when the switch 285 is open, the resistance wire is not in electrical connection with the power cord 88. In this manner, the electrical switch assembly 285 is of the doublepole type so that the user is not subjected to the resistance wire 140 being connected to an electrical power source when the switch assembly 285 is open.

An alternate embodiment thermostatic control 415 is illustrated in FIG. 17. This thermostatic control can be employed if it is not desired to have a fully automatic toaster and thereby eliminate the need for reset and trip mechanism 220. Therefore, thermostatic control 415 includes means for manually moving the heat-sensing element 288 from the inactive position to a heat-sensing position shown in broken lines. Parts in FIG. 17 which are identical to corresponding parts in FIG. 12 bear, for simplicity sake, the same reference numerals. It should be noted that electrical switch assembly 285 is exactly the same as employed with the fully automatically controlled arrangement disclosed in FIG. 12. Since no reset and trip mechanism is used, there is no trip lever 255 supported by mounting bracket 305. Threadedly mounted to the mounting bracket 305 is adjustment shaft 417 having a longitudinally extending passageway 418 extending completely therethrough, a threaded portion 419 which is in engagement with bracket 305, annular ring 420 having teeth 421 on its periphery and outer shaft portion 422 on which split retaining ring 424 is mounted. The threaded portion 419 has an end 426 for engagemerit with arm 319 in the same manner as illustrated in FIG. 12.

Carried on adjustment shaft 417 is a color control knob 430 preferably molded of a suitable plastic. The knob 430 is molded with a central bore 431 having an enlarged annular toothed portion 432 at one end of bore 430 and at the other end, an enlarged cavity 433. When the knob 430 is mounted to adjustment shaft 417, the bore 431 is in engagement with the outer shaft portion 422, and the enlarged toothed portion 432 is in engagement with the toothed annular ring 420 in a manner similar to that disclosed with reference to FIG. 12. For the purpose of limiting the angular movement of knob 430, the mounting bracket upright projection 342 enters into the knob and abuts against spaced portions thereof not shown in the drawing. Positioned within knob cavity 433 is a unitary spring actuator 435 having a compression spring portion 436 disposed around adjustment shaft 417 and an elongated pin portion 437 which extends through adjustment shaft passageway 418 so that it extends adjacent to the heat-responsive element 288 as pictured in solid lines in FIG. 17. Enclosing the knob cavity 433 is pushbutton 440 preferably formed from plastic material and being provided with a plurality of hook-shaped feet 441 which are adapted to spring inwardly when the button 440 is attached to the knob 430. Once assembled, the button hook-shaped feet 441 snap into spaced recessed areas 444 and prevent the withdrawal of the button from the knob. Therefore, the button 440 is in sliding engagement with knob 430 and rests on the top of spring actuator 435. The compression spring portion 436 is sufficiently strong to bias the button 440 to its outer position shown in FIG. 17. However, if the button 440 is depressed by the user, the button forces the spring actuator 435 downwardly so that the pin portion 437 moves the heat-responsive element 288 to its outer sensing position shown in broken lines. Once the user releases the button 440, the spring actuator 435 biases the button again to its outer position. Therefore, it should be appreciated that the user, merely by pressing on button 440, can move the heat-responsive element to the sensing position which closes the switch assembly 285 and start the toasting cycle.

The rotation of color control knob 430 causes the adjustment shaft to move vertically with respect to the mounting bracket 305 and, therefore, changes the location of arm 319 which governs the sensing position of heat-responsive element 288 thereby controlling the. degree of toasting. To facilitate the molding of color control knob 430, there are a plurality of passageways 443 leading from one end of the knob to the recessed areas'444 which receive the hook-shaped button feet 441.

As indicated hereinbefore, the thermostatic control and switch assembly 55 is enclosed by a rectangularly shaped control housing 50 defining an elongated slot 363 through which the thermostatic control adjustment shaft 345 extends. While the housing does bear indicia. 51 so that the user may easily select the color setting he desires, the primary purpose of the housing is to protect the thermostatic control and switch assembly 55. In order that consistent operation of the thermostatic control286 may be accomplished, it is required that no unusual or intermittent drafts be allowed to strike the thermostatic control. Thus, while it is desirable to have a controlled cooling of the thermostatic control 286, it is undesirable to have occasional drafts or even dirt reach the thermostatic control and switch assembly 55.

For the purpose of locking the control housing 50 to the shell 34, shell sidewall depressed area 260 is formed with two spaced, vertically aligned, crescent-shaped openings 446 at one end of the depressed area and a pair of similarly shaped and spaced openings 448 at the other end of the depressed area, as may be clearly seen in FIGS. 4 and 7. Control housing 50 is preferably formed from sheet material such as aluminum and has a pair of spaced angular arms or tabs 450 which are disposed to be inserted through openings 446 whereby the housing may'be pivoted due to this releasable hinge connection. It should be appreciated that housing arms 450 are bent sufficiently so that the ends thereof strike against the inside surface of shell sidewall 41 to insure a rigid fit between the housing and the shell. Along the opposite edge of housing 50 from the edge containing arms 450 are a pair of spaced latching inserts or tabs 452 including an outwardly, laterally angled barb 453. Thus, when housing arms 450 are inserted into openings 446 and housing 50 is pivoted, the pair of inserts 452 enter intoopenings 448, and barbs 453 latch to the toaster shell sidewall 41 since the free distance between the housing arms 450 and inserts 452 is greater than the distance between

openings

446 and 448. Consequently, there is a lateral biasing force imposed upon the housing 50 when assembled to the toaster shell 34. Furthermore, it can be seen in FIG. 7 that the angled housing arms 450 striking against the inside surface of shell wall 41 establishes a biasing force which tends to pivot the inserts 452 outwardly from the outer shell wall 41 thereby ensuring a rigid latching connection between the inserts and the shell wall. Therefore, the housing 50 is rigidly secured to the shell 34 in such a manner as to prevent any looseness therebetween. It should be appreciated that no additional fastening members are required to rigidly secure the control housing 50 to the toaster shell 34 and that the housing may be readily released from the shell simply by moving the housing inserts 452 inwardly so that barbs 453 can clear openings 448. The inserts 452 are accessible by inserting a thin suitable tool through end panel notched periphery 68.

Surrounding the thermal motor 150 is a reflector assembly 455 which reflects the radiant energy emitted from resistance wire 140 inwardly towards the toasting chamber 47 for uniformly toasting the bread and constitutes a thermal barrier between the thermal motor and the outer shell 34 so that the outer shell does not become excessively hot when the toaster is used continuously for prolonged periods of time. The reflector assembly 455 comprises two generally L-shaped plates 456 and 457 which, when assembled to the base 38, forms a relatively slender rectangular housing surrounding the thermal motor 150. Along the bottom edges of plates 456 and 457 are formed a plurality of downwardly extending projections which are spaced to be inserted within b'ase locking slots 99 and thereafter staked in such a manner as to rigidly lock both plates to said base. A long leg 454 of each L-shaped plate 456 and 457 is recessed inwardly so that it is as close as practical to the resistance wire 140. As seen in FIG. 7, the plates 456 and 457 trap the axle 177 so that it cannot be withdrawn from base 38. At the free end of the long leg 454 of each plate 456 and 457 is a vertical edge 459 as can be seen in FIG. 5 including two spaced, upwardly extending, L-shaped legs 460, and disposed therebetween is a wedge-shaped member 461 having a downwardly facing surface 462. Each of the L-shaped plates 456 and 457 have a free end shorter leg 458 containing two spaced vertically extending slots 464 adapted to receive L- shaped legs 460 and slot 465 positioned therebetween and located to receive wedge-shaped member 461. Thus, in assembly, the two L-shaped legs 460 are forcibly inserted into slots 464 against the resistive force caused by wedge-shaped member 461 abutting against shorter leg 458 and are moved upwardly until said wedge-shaped member 461 springs in slot 465, and downwardly facing surface 462 is locked within slot 465 making a rigid connection between the reflector plates. In order to disassemble the plates, it is necessary to spring the wedge-shaped member 461 from slot 465 to allow the L- shaped legs 460 to move downwardly a sufficient distance so that they may be withdrawn from slots 464. Therefore, there is provided a connection means between the two L-shaped plates 456 and 457 and base 38 so that these three members may be secured without the need of additional fastening members. The slots 464 are formed in a stepped configuration having the ends thereof in one vertical plane and the center portion recessed therefrom in order that the slot may be easily stamped using known stamping techniques. This is necessary because the L-shaped plates 456 and 457 are fabricated from relatively thin sheet material, and it would not be practical to stamp a slot having a width approximately equal to the thickness of the plate material. Therefore, when the L-shaped legs 460 are inserted into slot 464, the legs bear only against the center portion of the slot and the opposite sides of the upper and lower portions of the slot.-

Reflector plate 456 as can be seen in FIG. 4 is fonned with a window 470 defined by an outwardly inclined lower flap 471 and an inwardly, downwardly declined upper flap 472. The window 470 is positioned in front of thermostat heat-responsive element 288 so that the element may sense the surface temperature of a slice of bread disposed on the bread carriage. Both the upper and lower flaps 471 and 472 are arranged to prevent vertically rising air currents from impinging upon the heat-responsive element 288 causing erratic action thereof. At one side of window 470, as can be seen in FIG. 7, is an inwardly directed integral tab 473 to which is riveted an insulator 474. The purpose of insulator 474 is to prevent resistance wire from extending in front of window 470 and thereby effect the operating characteristic of thermostatic control 286. That is to say, during the toasting cycle, it is possible that a strand of resistance wire 140 might sag or that the vertical movement of the thennal motor might permit a strand of resistance wire to be sufficiently close to window 470 to adversely effect the operation of heat-responsive element 288. If the resistance wire starts to come too close to window 470, insulator 474 engages the resistance wire and prevents it from moving in front of the window. Also formed in reflector plate 456, as can be seen in FIG. 4, are an elongates opening 476 through which the thermostatic control trigger lever 255 extends, and two spaced openings 478 through which lead wires 413 gain access to the switch assembly 285. To assist in positioning the reflector assembly 455 with respect to shell 34,

each plate 456 and 457 is formed with a laterally extending finger 479 engageable with the shell whereby the reflector assembly is properly positioned due to the fingers 479 and the edges of the L-shaped plates short leg 458 contacting the shell 34.

Preventing the slices of bread on the bread carriage from engaging the electrical resistance wire 140 are four identical bread guides 482, shown inFlGS. 20 and 21, which extend from the base flanges 94 and 95 to the

shell slot flanges

44 and 45. Preferably, the bread guides are stamped from sheet material and include an upper outwardly curved border 483, spaced side borders 484, bottom border 485 and four vertically extending and inwardly projecting

ribs

486, 487, 488 and 489 which are attached at the top to upper curved border 483 and at the bottom to bottom border 485. These ribs are angled slightly with respect to the borders so that when assembled within the toasting chamber, the ribs extend in approximately a vertical plane. Each of the

ribs

486, 487, 488 and 489 are joined to the upper curved border in such a manner as to define slots 490 between the top end of said ribs and said upper border and disposed below said border. It should be noted, however, that the upper end of rib 487 does not contain such a slot. When the bread guide is assembled within the toaster, the upper end of rib 487 is received within vertically extending notches 492 spaced along the toaster shell slot flanges 44 and 45shown in FIG. 4, and the slots 490 receive the bottom edge of either

shell flange

44 or 45. With this construction, the upper portion of the bread guide 482 is securely locked to the toaster shell and cannot move in any direction except downwardly. That is to say, movement towards or away from the toasting chamber 47 is prevented by the toaster slot flange being nested within the bread guide slots 490, and longitudinal movement with respect to the toasting chamber is prevented by the upper portion of rib 487 being nested within shell flange notch 492.

The bread guide bottom border 485, as can be seen in FIG. 6, includes two integral spaced clip portions 494 adapted to receive the base flange 94 or 95. Oppositely disposed to the downwardly directed clip portions 494 is an upwardly extending tongue 495 positioned therebetween and angled outwardly so that the base flange is held to the bottom border under tension preventing any looseness therebetween. Furthermore, there are two downwardly directed fingers 496 which are disposed to abut against the top surface of the base flange and thereby control the depth of insertion of the base flange into the clip portions 494. Thus, the fingers 496 constitute an abutmentor stop elements against which the base flange abuts. As disclosed hereinbefore, the base flanges 94 and 95 include abutment flaps 97 and 98 which are spaced so they are adjacent to the inner vertical surfaces of clip portions 494 to insure proper location of the bread guides and to prevent any lateral movement thereof. Consequently, the top of the bread guide 492 is securely attached to the toaster shell slot flange, and the lower portion thereof is securely attached to the base flange so that the bread guides are accurately located and are not permitted to move once assembled. It should be appreciated that no additional fastening elements are necessary to hold the bread guides in their proper position. As indicated by the drawings, the four bread guides are disposed so that one is on each side of two slices of bread supposing that two slices of bread are inserted into the shell entrance slot 43.

Catching the crumbs which fall from slices of bread while they are disposed within the toasting chamber 47 is a crumb tray 500, shown in FIG. 4, preferably stamped from sheet metal and formed with upturned periphery 50 for retaining the crumbs therein. The upturned periphery along the back edge of the crumb tray extends laterally from both sides of the crumb tray to form short aligned trunnions 502 which are received in end panel aligned recesses 80 and 81 so that the crumb tray 500 is pivotally mounted to the

end panels

64 and 65. The upturned periphery along the front edge of the crumb tray is flattened to form a handle portion 503. For holding the crumb tray in the closed position, the crumb tray 500 is provided with a resilient spring clip 505 which is riveted in place. The spring clip is disposed to latch in locking engagement with base flange opening 103. Whenever the user intends to clean the bottom of the toaster, the crumb tray handle portion 503 is grasped and pivoted downwardly so that spring clip 505 disengages itself from base flange opening 103 and tray trunnions 502 pivot within end panel recesses and 81. After the bottom of the toaster has been cleaned, the crumb tray 500 can be rotated upwardly until the spring clip 505 once again engages the base flange opening 103 thereby closing the base opening 96.

It is desirable during the heating and cooling toasting cycles that the thermal motor move in a vertical controlled manner so that the thermal motor does not tend to move towards either of the end panels. To accomplish controlled longitudinal movement of the thermal motor, the

toaster shell flanges

44 and 45 are formed with vertically depending fingers 508 defining opposed vertical surfaces 509 which receive the crosspiece upper leg 187 therebetween. As has been described hereinbefore, the upper leg crosspiece 187 is rigidly secured to

upper trusses

133 and 134. The longitudinal displacement between vertical surfaces 509 is just sufficient to accommodate the thickness of crosspiece upper leg 87 plus a working clearance. Therefore, when the upper truss assembly 132 moves vertically, its movement is controlled by the shell flange fingers 508 preventing any longitudinal movement of the upper truss assembly 132.

As is evident from the above explanation, the present toaster is easily and economically assembled and provides a structure requiring a minimum thickness to conserve kitchen counter space. Moreover, the various components are related together in such a manner as to provide a well constructed toaster which performs a high-quality toasting operation. While only two embodiments of the present invention have been disclosed and illustrated, it will be understood that the present invention is capable of various changes and modifications. It is intended in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the present invention.

What we consider new and desire to secure by Letters Patent of the United States is:

1. A thermostatic control comprising a rigid frame, a heatresponsive element mounted to said frame and arranged to move from a sensing position to an inactive position when heated, a unitary sheet metal bracket secured to said frame, said bracket supporting adjustable means, a resilient arm formed from said bracket which is biased toward said adjustable means, said resilient arm being variably positionable by said adjustable means to form a stop means for limiting the movement of said element for determining the sensing position and the temperature at which said element moves from said sensing to said inactive position, reset means pivotally mounted to said bracket and engageable with said element for moving it from said inactive position to said sensing position for resetting said element, and electrical switch means mounted on said frame and retained in position by an end portion of said bracket remote from said resilient arm wherein said switch means is responsive to the motion of said element from its sensing position to its inactive position.

2. The thermostatic control of claim 1 wherein said adjustable means including a threaded shaft threadedly received by said bracket with one end of said shaft having a reduced diameter extension defining a shoulder thereon, said resilient arm having a raised inclined portion associated therewith at the periphery of said aperture which engages said shoulder of said shaft extension.

3. The thermostatic control of claim 2 wherein said threaded-shaft other end is adapted for releasably securing a knob thereto, said knob formed with a recess facing said bracket, an integral upstanding projection from said bracket extending into said knob recess for limiting the angular movement of said knob and threaded shaft with respect to said bracket.

4. The thermostatic control of claim 1 wherein said rigid frame has an elongated channel having bight and leg portions with a pair of aligned notches at the juncture of said channel bight and leg portions, said electrical switch means including an elongated insulator transversely disposed to said frame and having a pair of opposed projections adapted to enter into said frame notches, said insulator being provided with slot means for receiving said bracket end portion, said end portion of said bracket being resilient and biasing said insulator towards said frame thereby locking said insulator to said frame.

5. A thermostatic control comprising a rigid elongated frame, a heat-responsive thermostatic snap-action element mounted to one side of said frame, an elongated ceramic switch insulatormounted transversely on the other side of said frame, said insulator formed with a pair of parallel spaced passageways extending parallel to said frame on both sides thereof, switch contact blades received within said passageways and secured to said insulator, actuator means attached to one bladeon each side of said frame and disposed for engagement with said thermostatic snap-action element whereby the movement of said element actuates said switch blades, at least one of said passageways having straight sidewalls and a recess shoulder, said switch contact blade received in said passageway provided with tapered upturned opposed edges and an integral finger angled outwardly toward the wider portion of the tapered edges whereby said blade is secured to said insulator by inserting and forcing said blade tapered edges against said, passageway walls and said blade finger engages said'insulator recess shoulder for preventing the withdrawal of said blade.

6. A thermostatic control comprising a rigid elongated frame, a heat-responsive thermostatic snap-action element mounted to one side of said frame, an elongated ceramic switch insulator mounted transversely on the other side of said frame, said insulator formed with a pair of parallel spaced passageways extending parallel to said frame on both sides thereof, switch contact blades received within said passageways and secured to said insulator, actuator means attached to one blade on each side of said frame and disposed for engagement with said thermostatic snap-action element whereby the movement of said element actuates said switch blades, said frame being formed with opposed spaced notches and a spaced opening, said switch insulator having a cutout central portion with a pair of inwardly projecting ribs adapted for being received in said frame notches when said frame is received within said cutout central insulator portion, said actuator means extending into said frame opening and in engagement with said snap-action element.

7. A thennostatic control comprising a frame, a heatresponsive element mounted to said frame and arranged to move from a sensing position to an inactive position when heated, adjustable means mounted on said frame engageable with said element for determining the sensing position and the temperature at which said element moves from said sensing to said inactive position, a hollow shaft threadedly secured to said frame and engageable with said adjustable means for selectively locating the sensing position of said element, actuator means disposed at the end of said shaft remote from said frame and extending through said shaft for moving said element from said inactive position to said sensing position, a button mounted to said shaft and disposed so that depression of said button causes said actuator means to move said element to said sensing position.

8. The thermostatic control of claim 7 wherein said actuator means including a pin portion extending through said hollow shaft and a spring portion biasing said button away from said frame, said spring portion preventing contact between said pin portion and said element when said element is in said sensing position unless said button is depressed.

9. The thermostatic control of claim 8 wherein said pin portion and said spring portion integrally formed from spring wire.

10. The thermostatic control of claim 7 including a control knob secured to said shaft and rotatable therewith for selectively determining the sensing position of said element, said button being slidably mounted on said knob so that said button is movable axially with respect to said shaft, said actuator means biasing said button away from said frame.

Claims

5. A thermostatic control comprising a rigid elongated frame, a heat-responsive thermostatic snap-action element mounted to one side of said frame, an elongated ceramic switch insulator mounted transversely on the other side of said frame, said insulator formed with a pair of parallel spaced passageways extending parallel to said frame on both sides thereof, switch contact blades received within said passageways and secured to said insulator, actuator means attached to one blade on each side of said frame and disposed for engagement with said thermostatic snap-action element whereby the movement of said element actuates said switch blades, at least one of said passageways having straight sidewalls and a recess shoulder, said switch contact blade received in said passageway provided with tapered upturned opposed edges and an integral finger angled outwardly toward the wider portion of the tapered edges whereby said blade is secured to said insulator by inserting and forcing said blade tapered edges against said passageway walls and said blade finger engages said insulator recess shoulder for preventing the withdrawal of said blade.

7. A thermostatic control comprising a frame, a heat-responsive element mounted to said frame and arranged to move from a sensing position to an inactive position when heated, adjustable means mounted on said frame engageable with said element for determining the sensing position and the temperature at which said element moves from said sensing to said inactive position, a hollow shaft threadedly secured to said frame and engageable with said adjustable means for selectively locating the sensing position of said element, actuator means disposed at the end of said shaft remote from said frame and extending through said shaft for moving said element from said inactive position to said sensing position, a button mounted to said shaft and disposed so that depression of said button causes said actuator means to move said element to said sensing position.