GB1581045A

GB1581045A - Toaster

Info

Publication number: GB1581045A
Application number: GB4615876A
Authority: GB
Original assignee: Prestige Group Ltd
Current assignee: Prestige Group Ltd
Priority date: 1976-11-05
Filing date: 1976-11-05
Publication date: 1980-12-10

Description

(54) TOASTER (71) We, THE PRESTIGE GROUP LIMI- TED, a British Company of 14/18 Holborn, London E.C. 1, do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed, to be particularly described in and by the following statement: - This invention relates to a toaster.

Conventional electric toasters usually comprise one or more vertical slots, each receiving a slice of bread which is lowered into the slots on a spring biased carrier.

The carrier is normally connected to a slidable lever at the side of the toaster, which lever is depressed so as to lower the slice or slices of bread in the vertical slots.

As the lever is depressed, it winds up a clockwork mechanism which operates to trip out the spring biased lever after a predetermined time. During this time, each slice of bread is heated on its major surface or surfaces by heating elements arranged within the body of the toaster.

These elements usually take the form of wire coils which are strung in a plane de fi.ning a major vertical wall of the respective vertical slot. A plurality of elements may be provided in respective planes so as to toast both sides of each slice of bread simultaneously. At the end of the predetermined time, the clockwork mechanism releases the lever so that the food carrier rises under bias to eject the slices of bread.

One of the disadvantages of conventional toasters, as described above, is that a slice of bread is not toasted evenly. For exexample, there may be a reduction in the amount of heat radiated to the edges of the slice which are pale in comparison to the toasted major surface. Further conventional toasters cannot be used to toast thick slices of bread since the slices have to be inserted into the toaster through predetermined sized slots. Another disadvantage of the conventional toaster is that it cannot be used to prepare a toasted snack which consists of a layer of food placed cn a layer of bread. An example of such a snack is Welsh Rarebit wherein a layer of cheese is toasted simultaneously with the bread. One of the objects of the present invention is to provide a toaster which will evenly toast food such as a slice of bread.

Another object, is to provide a more versatile toaster which can be used, for example to provide toasted snacks.

According to the present invention there is provided a toaster comprising a first heating element, a second heating element spaced apart from and substantially vertically below the first heating element, a support for an item of food, and drive means adapted to move an item of food on the support in a substantiallp horizontal plane between the first and second heating elements and means for adjusting the vertical distance between the first heating element and the support.

The means for adjusting the distance between the first heating element and the support enables the toaster to accommodate items of food of various thickness.

The item of food is carried in a substantially horizontal plane through the body of the toaster so that toasted snacks can be prepared. E.g. a slice of bread on the support can be covered with a layer of food to provide a toasted snack. In a preferred embodiment the drive means are adapted to move the support between the heating elements.

Preferably the heating elements are elongate, the longitudinal axis extending transversely of the direction of the relevant motion. An elongate heating element enables the food to be toasted sequentially as each part of the food passes the heating element.

Both sides of the item of food are toasted as the item of food to be toasted is moved through a gap between the pair of heating elements. The first heating element is adapted to toast the top surface of the item of food and the second heating element is adap- ted to toast the lower surface (e.g. the undersurface of the slice of bread) through the support. The height of the upper heat ing element above the support is adjustable, primarily to enable the toaster to accommodate various thicknesses of food on the support. The adjustment can also be used to vary the intensity of heat receivd by the food as it passes the heating element. If desired, the distance between the lower heating element and the support could also be adjustable.However the amount of heat reaching the item of food is preferably regulated by adjusting the speed of the relative motion of the support past the heating element or elements. The support may be, for example, a grid type structure compris- ing a rigid framework connected by thin wires or the like for supporting the food.

The drive means for moving an item of food on the support is preferably activated by a spring operated mechanism (e.g. a clockwork mechanism) or an electrical motor. For example, the support may in dude a rack which is driven by a pinion coupled to the shaft of a spring operated mechanism or electrical motor. In an alternative arrangement a form of belt drive may be employed to advance the food with respect to the heating elements. Moreover, the item of food may be slidably supported on a fixed tray or support, motion being imparted to the food by spiked wheels or a friction drive. The arrangement may be such that a food support is pushed in one direction to wind up a clockwork mechanism which advances the tray at a controlled rate relative to the heating element.The tray may be connected to biasing means so that it is returned to a starting position after a predetermined time.

However, various arrangements are possible incorporating either electrical or mechanical motors and either with or without biasing arrangements. It may also be feasible to cause the relative motion by a weight operated mechanism. However, preferably the food support is driven by a spring operated mechanism or by an electric motor, which is adapted to be set in motion by, and the speed of which can be controlled by, a control or controls situated on the housing of the toaster. The speed of the spring operated mechanism may be controlled by a variable governor of knows type (e.g. of the air vane or escapement type). In an embodiment, the support can be arranged to actuate an audible or visual signal at the finish of its travel to indicate completion of the toasting operation.

In a preferred embodiment of the invention, the toaster comprises a body which houses a pair of spaced parallel elongate heating elements, a' food support which can be moved between the heating elements in a direction substantially perpendicular thereto, and drive means for imparting the latter movement at a controlled rate.

The heating elements are preferably elec trical heating elements of the sheathed wire type wherein a cylindrical sheath contains insulating material which locates a coaxial conductor. This type of element is the type used, for example, in electrical kettles.

Alternatively, it may be a coil of wire supported under tension, or located in a heat resistant tube when may be made, for example, of silica.

A toaster in accordance with the invention will now be described by way of example with reference to the accompanying drawing in which: Figure 1 is a perspective view of the toaster together with two slices of bread ready to be toasted.

Figure 2 is a partly broken away perspex tive view of the toaster of Figure 1 showing some of the internal mechanism.

Figure 3 is a partly broken away perspective view of the toaster of Figure 1 showing some of the other internal mechanism.

Referring now to the drawings, first of all particularly in Figure 1, the toaster comprises a housing 1 including front and rear walls 2, 3 and side walls 4, 5. In the front wall 2 there is a slot 6, of inverted T configuration. Rear wall 3 has a similar corresponding slot (not shown). A food support tray 7, for supporting items of food to be toasted (such as the slices of bread 8, 81) is of such a size that it can pass through the slots in walls 2, 3 between heating elements, 9 and 10 contained in the housing (the heating elements 9, 10 are more fully described with reference to Figure 3) from a first position, similar to that shown in Figure 1, in which most of the tray protrudes out of the front slot 6 to a second position in which most of the tray protrudes out of the slot in the rear wall 3 of the housing. The tray comprises a number of cross wires attached to a rigid metal framework 12. One side of the rigid framework 12 is in the form of a rack 13 forming one component of a rack and pinion gear (described more fully with reference to Figure 2 below).

The side wall 4 of the housing 1 has a vertical slot 14 in it, through which protrudes a shaft 15 carrying a knob 16. The side wall 4 also carries two rotatable control knobs 17 and 18 mounted on spindles 19 and 20 respectively (see Figures 3 and 2) which pass through holes in side wall 4.

Turning now to Figure 2, the figure shows the drive mechanism for driving the tray 13.

The shaft 15, of the knob 16, is attached to a vertical rack 21 which meshes with a pinion 22 to form a rack and pinion gear.

The rack 21 is adapted to move in a vertical plane under the influence of a spring 23 one end of which is attached to the top of the rack and the other end of which is attached to a suitable support on the housing 1. The pinion 22 is mounted on a drive shaft 24. Mounted on the other end of the drive shaft 24 is a second pinion 25 which engages with the rack 13 of the tray 7. Thus when the vertical rack 21 is pulled to its lowermost position, as shown in Figure 2, by means of the knob 16 most of the tray 11 protrudes out of the front of the housing, as also shown in Figure 2.

If the knob 16 is then released the rack 21 will be gradually raised vertically under the influence of the spring 23. This movement will cause rotation of the pinion 22 and hence of the shaft 24 and the pinion 25. Rotation of the pinion 25 causes movement of the rack 13 until the rack 21 is Pt its highest position when most of the tray 7 will protrude out of the slot in the rear of the housing.

To maintain the rack 13 in contact with the pinion 25, the tray 7 runs in guide means and is pressed upwards by means of leaf springs (not shown) pressing against the lower surface of the tray. If it is desired to remove the tray from the housing, e.g.

for storage purposes, the leaf springs may be depressed manually and the tray 7 then removed from its guide means.

In order to regulate the speed of rotation of the drive shaft 24, and hence the speed of movement of the tray 7, it is connected to a variable governor by a gear train as shown diagrammatically in Figure 2. Thus the spindle 20 carries a gear wheel 26 which mates with the input gear of a variable governor of known type (not shown). The output of the governor is transmitted by gear wheel 27 and gear wheel 28 (the latter mounted on the drive shaft 24) to the shaft 24 such that the speed of the rotation of the shaft may be controlled by regulating the governor; the governor is regulated by adjusting the angular position of the spindle 20 by means of the knob 18.

Turning now to Figure 3, this figure shows the heating elements. The heating elements 9 and 10 are U-shaped electrical elements of the sheathed wire type. The lower element 10 is fixedly mounted in a horizontal plane between vertical plates 29 and 30 within the housing 1 (it should be understood that the gear mechanism shown in Figure 2 is situated between the plate 29 and side wall 4 of the housing).

Each plate 29 and 30 contains a pair we parallel vertical slots 31, 32 and 33, 34 situated vertically above the limbs of the U-shaped lower heating element 10. The limbs of the U-shaped upper heating element 9 pass through the slots and are retained within the slots by means of small plates 35, 36. The slots and the two heating elements are so positioned that the tray 7, when driven by the mechanism previously described, passes beneath the upper heating element 9 and above the lower heating element 10. The small plates 35, 36 are pivotally connected to the spindle 19 by means of connections 37, 38 such that the rotation of the spindle in an anti-clockwise direction as shown by the arrow in Figure 3 causes the small plates 35 and 36 to be raised vertically within the slots 32, 32, 33, 34.Rotation of the spindle 19 in the op- posite direction will, of course, lower the upper heating element 9. The heating elements are adapted to be connected to a source of electrical supply in the usual manner.

In use, the control knob 17 is set according to the thickness of the food desired to be toasted (i.e. the knob is calibrated in measurements of thickness). As explained above, adjustment of the knob 17 causes adjustment of the spindle 19 and hence adjustment of the height of upper heating element 9 about the tray 7. The control knob 18 is set for the desired speed of travel of the tray 7. Since the speed of travel determines the amount of heat reaching the food the knob 18 is calibrated in measurements of "browning". As explained above adjustment of the knob 18 adjusts the speed of travel by adjusting the governor. The knob 16 is then brought to its lowermost position in the slot 14 which as mentioned above brings the tray 7 to the position shown in Figure 1.The food is then placed on the tray 7 and the knob 16 released so starting the movement of the tray between the heating elements. When the knob 16 reaches its uppermost position the food on the tray has passed through the heating elements and out of the slot in the rear of the housing. The toasted food may then be removed.

WHAT WE CLAIM IS: 1. A toaster comprising a first heating element, a second heating element spaced apart from and substantially vertically below the first heating element, a support for an item of food, and drive means adapted to move an item of food on the support in a substantially horizontal plane between the first and second heating elements and means for adjusting the vertical distance between the first heating element and the support.

2. A toaster as claimed in Claim 1 wherein the drive means are adapted to move the support in the substantially horizontal plane between the heating elements.

3. A toaster as claimed in Claim 2 wherein the heating elements are donga- ted, the longitudinal axis of the heating elements extending transversely of the direction of motion of the support.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. of the rack and the other end of which is attached to a suitable support on the housing 1. The pinion 22 is mounted on a drive shaft 24. Mounted on the other end of the drive shaft 24 is a second pinion 25 which engages with the rack 13 of the tray 7. Thus when the vertical rack 21 is pulled to its lowermost position, as shown in Figure 2, by means of the knob 16 most of the tray 11 protrudes out of the front of the housing, as also shown in Figure 2. If the knob 16 is then released the rack 21 will be gradually raised vertically under the influence of the spring 23. This movement will cause rotation of the pinion 22 and hence of the shaft 24 and the pinion 25. Rotation of the pinion 25 causes movement of the rack 13 until the rack 21 is Pt its highest position when most of the tray 7 will protrude out of the slot in the rear of the housing. To maintain the rack 13 in contact with the pinion 25, the tray 7 runs in guide means and is pressed upwards by means of leaf springs (not shown) pressing against the lower surface of the tray. If it is desired to remove the tray from the housing, e.g. for storage purposes, the leaf springs may be depressed manually and the tray 7 then removed from its guide means. In order to regulate the speed of rotation of the drive shaft 24, and hence the speed of movement of the tray 7, it is connected to a variable governor by a gear train as shown diagrammatically in Figure 2. Thus the spindle 20 carries a gear wheel 26 which mates with the input gear of a variable governor of known type (not shown). The output of the governor is transmitted by gear wheel 27 and gear wheel 28 (the latter mounted on the drive shaft 24) to the shaft 24 such that the speed of the rotation of the shaft may be controlled by regulating the governor; the governor is regulated by adjusting the angular position of the spindle 20 by means of the knob 18. Turning now to Figure 3, this figure shows the heating elements. The heating elements 9 and 10 are U-shaped electrical elements of the sheathed wire type. The lower element 10 is fixedly mounted in a horizontal plane between vertical plates 29 and 30 within the housing 1 (it should be understood that the gear mechanism shown in Figure 2 is situated between the plate 29 and side wall 4 of the housing). Each plate 29 and 30 contains a pair we parallel vertical slots 31, 32 and 33, 34 situated vertically above the limbs of the U-shaped lower heating element 10. The limbs of the U-shaped upper heating element 9 pass through the slots and are retained within the slots by means of small plates 35, 36. The slots and the two heating elements are so positioned that the tray 7, when driven by the mechanism previously described, passes beneath the upper heating element 9 and above the lower heating element 10. The small plates 35, 36 are pivotally connected to the spindle 19 by means of connections 37, 38 such that the rotation of the spindle in an anti-clockwise direction as shown by the arrow in Figure 3 causes the small plates 35 and 36 to be raised vertically within the slots 32, 32, 33, 34.Rotation of the spindle 19 in the op- posite direction will, of course, lower the upper heating element 9. The heating elements are adapted to be connected to a source of electrical supply in the usual manner. In use, the control knob 17 is set according to the thickness of the food desired to be toasted (i.e. the knob is calibrated in measurements of thickness). As explained above, adjustment of the knob 17 causes adjustment of the spindle 19 and hence adjustment of the height of upper heating element 9 about the tray 7. The control knob 18 is set for the desired speed of travel of the tray 7. Since the speed of travel determines the amount of heat reaching the food the knob 18 is calibrated in measurements of "browning". As explained above adjustment of the knob 18 adjusts the speed of travel by adjusting the governor. The knob 16 is then brought to its lowermost position in the slot 14 which as mentioned above brings the tray 7 to the position shown in Figure 1.The food is then placed on the tray 7 and the knob 16 released so starting the movement of the tray between the heating elements. When the knob 16 reaches its uppermost position the food on the tray has passed through the heating elements and out of the slot in the rear of the housing. The toasted food may then be removed. WHAT WE CLAIM IS:

1. A toaster comprising a first heating element, a second heating element spaced apart from and substantially vertically below the first heating element, a support for an item of food, and drive means adapted to move an item of food on the support in a substantially horizontal plane between the first and second heating elements and means for adjusting the vertical distance between the first heating element and the support.

4. A toaster as claimed in Claim 2 or

3 wherein the heating elements are electric heating elements of the sheathed wire type.

5. A toaster as claimed in any one of Claims 3 and 4 wherein the drive means are spring operated or adapted to be actuated by an electric motor.

6. A toaster as claimed in any one of the Claims 2 to 5 wherein the speed of movement of the support is adjustable.

7. A toaster as claimed in any one of the preceding claims which include means for adjusting the vertical distance between the second heating element and the support.

8. A toaster substantially as hereinbefore described with reference to and as illustrated in any one of the Figures of the accompanying drawings.