GB2285389A - Toaster - Google Patents

Abstract

A toaster (10) has a casing (11), a cavity (12) in the casing, a heating element on opposite sides of the cavity, a cartridge (15) in the cavity for supporting a slice of bread to be toasted by the heating element, said cartridge being movable between an upper position in which a said slice is partially extending outside the cavity (12) and a lower position in which the slice is wholly within the cavity and being biassed towards its upper position by a spring (29), a timer to determine the toasting time of the slice, and holding means (23) to hold the cartridge against moving upwards into the upper position before and after completion of the bread toasting, the means (23) being manually releasable. The slice is thus held within the toaster at completion of toasting and allows crispness to be maintained for longer periods compared to conventional ejection. <IMAGE>

Description

TOASTER The present invention relates to a toaster.

According to the invention, there is provided a toaster which comprises a casing, a cavity inside the casing, an electrical heating element provided on opposite sides of the cavity, a cartridge provided within the cavity for supporting a slice of bread to be toasted by the heating element inside the cavity, said cartridge being vertically movable between an upper position in which a said slice of bread is partially extending outside the cavity and a lower position in which a said slice of bread is wholly within the cavity and being resiliently biassed towards its upper position by a spring, a timer adapted to determine the toasting time of a said slice of bread, and holding means adapted to hold the cartridge against moving upwards into the upper position before and after completion of the bread toasting, said holding means being manually releasable.

In a preferred embodiment, the holding means is adapted in a first stage to hold the cartridge in the lower position for bread toasting and in a second stage to hold the cartridge in an intermediate position slightly above the lower position for toast temperature keeping.

More preferably, the cartridge in the intermediate position is sufficiently low to retain a said slice of bread substantially within the cavity.

In a specific arrangement, the holding means is provided in the first stage by a solenoid and in the second stage by a latch.

The toaster may incorporate an electrical switch which is arranged to turn on and off the heating element in response to the cartridge moving to and away from the lower position, respectively.

The toaster may comprise an electronic control circuit including a solid-state timer for determining the toasting time of a said slice of bread.

The invention will now be more particularly described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of an embodiment of a toaster in accordance with the invention; Figure 2 is a perspective view of an internal operating mechanism of the toaster of Figure 1; Figures 3A and 3B are side and end views of the operating mechanism of Figure 2, in a first operating condition; Figures 4A and 4B are side and end views of the operating mechanism of Figure 2, in a second operating condition; and Figures 5A and 5B are side and end views of the operating mechanism of Figure 2, in a third operating condition.

Referring firstly to Figures 1 to 3B of the drawings, there is shown a toaster 10 embodying the invention, which toaster 10 comprises a generally flat casing 11 having a elongate cavity 12 into which a slice of bread for toasting is to be inserted, and an operating mechanism 13 provided within the casing 11. The operating mechanism 13 has first 13A and second 13B parts. The first part 13A is formed by an electrical heating element (not shown) provided on opposite sides of the cavity 12 for heating a slice of bread placed inside the cavity 12, an array of metal bars 14 located immediately in front of the heating element for safeguarding the slice of bread against the heating element, and a horizontal internal cartridge 15 extending along the length of the cavity 12 for supporting thereon the slice of bread to be toasted.

The second part 13B of the operating mechanism 13 is designed to control the operation of the heating element and to move and control the movement of the bread cartridge 15. This second part 13B is provided next to one end of the cavity 12 and has a vertical metal mounting plate 16 shielding off the heat of the heating element. The mounting plate 16 has a central vertical slot 16A. The second part 13B further includes a vertical metal shaft 17 supported by the mounting plate 16, a movable vertical metal carrier plate 18, which is slidably supported on the shaft 17 by means of a pair of horizontally extending and apertured integral top and bottom lugs 18C, for vertical movement along the shaft 17, and a metal bracket 19 fixed on the carrier plate 18 by a pair of rivets 20.The near end of the bread cartridge 15 passes through the slot 16A of the mounting plate 16 from behind and is then connected to the carrier plate 18 by a pair of integral lugs (not shown). These lugs pass through corresponding slots (not shown) on the carrier plate 18 and are then twisted to secure the connection such that the cartridge 15 is movable with the carrier plate 18.

The carrier plate 18 has a first integral arm 18A extending at right angles thereto, across which arm 18A and a flanged top side of the mounting plate 16 a vertical coil spring 29 is stretched to resiliently bias the carrier plate 18 upwards.

The bracket 19 has a pair of horizontal, mutually perpendicular, first and second arms 19A and 19B. The first arm 19A extends beyond one side of the carrier plate 18 and through the wall of the toaster casing 11 to engage a slide knob 21. The second arm 19B extends away from the carrier plate 18 and supports thereon a U-shaped soft iron plate 22 by means of a plastic holder 30. An electromagnetic solenoid 23 is provided directly below the Ushaped plate 22 for in operation holding the U-shaped plate 22 close.

The operating mechanism 13 further includes an electronic control circuit (not shown) for controlling the operation of the solenoid 23 and the heating element. The electronic circuit includes a normally-open electrical switch (not shown) for controlling the supply of mains power to the heating element. This electrical switch is located such that it will be mechanically closed by the carrier plate 18 when the carrier plate 18 is moved fully downwards against the switch operating member. At the same time when the electrical switch is closed to turn on the heating element, the solenoid 23 will also be energised under the control of the control circuit in order to retain the U-shaped plate 22 close and thus the carrier plate 18 and the bread cartridge 15 fully downwards, as hereinafter more fully described.

The electronic control circuit further includes a solidstate timer (not shown) for controlling the operating time of the solenoid 23 and hence the heating element in order to determine the browniness of the toast to be made. This timer is presettable by means of a turning knob 28 exposed outside the toaster casing 11.

The carrier plate 18 has a second integral arm 18B which is bent. Directly below the arm 18B there is provided a latch member 24 which is hinged onto a flanged bottom side of the mounting plate 16 and is resiliently biassed upwards by an elbow spring 25. Upon sufficient downward movement of the carrier plate 18, its second arm 18B will be engaged by the top end of the latch member 24, whereby the carrier plate 18 and the bread cartridge 15 are held against moving upwards under the action of the spring 29. The latch member 24 has at its top end a fixed horizontal pin 26 which projects out of the wall of the casing 11 to engage a pushbutton 27.

Reference is also made to Figures 4A to 5B of the drawings.

The initial operation of the toaster 10 is generally similar to that of conventional toasters. A user firstly inserts a slice of bread into the cavity 12, resting on the cartridge 15, of the toaster 10, and subsequently slides the knob 21 fully downwards in order to move the carrier plate 18 and hence the bread cartridge 15 down so as to bring the slice of bread completely inside the toaster 10.

At this time, the electrical switch of the electronic circuit is closed by the carrier plate 18 to enable energization of the heating element. Simultaneously, the solenoid 23 is also energised and the timer starts to run.

In the fully downward position of the carrier plate 18, the U-shaped plate 22 carried thereon comes into physical contact with and is thereby magnetically attracted by the solenoid 23. The solenoid 23 holds the carrier plate 18 and the bread cartridge 15 in their lowermost position against the action of the spring 29. During the downward movement of the carrier plate 18, its second arm 18B will move past the top end of the latch member 24.

At the end of the bread toasting operation, which is determined by the timer, the control circuit will switch off the solenoid 23. Switching off of the solenoid 23 will release the U-shaped plate 22 and hence the carrier plate 18 and the bread cartridge 15 from their lowermost position. As a result, the electrical switch is permitted to return to its normally-open condition and the heating element is therefore turned off. Under the action of the spring 29, the carrier plate 18 will move upwards until its second arm 18B is caught by the latch member 24. At this time, the carrier plate 18 and hence the bread cartridge 15 are held in an intermediate position, slightly above their lowermost position, as illustrated in Figures 4A and 4B.

In this intermediate position, the slice of bread stays substantially fully inside the toaster cavity 12, where the temperature and hence the crispiness of the freshly made toast will be maintained for a comparatively longer period of time than the situation in which the toast is partially exposed and ready for removal as in conventional toasters.

In order to remove the toast from the toaster 10, the user depresses the pushbutton 27 so as to release the carrier plate second arm 18B from the latch member 24, thereby permitting the carrier plate 18 and thus the bread cartridge 15 to move fully upwards under the action of the spring 29. In this uppermost position, the toast is partially exposed for removal. After the toast has been removed, the toaster is ready for use again.

In this particular embodiment, the bread cartridge 15 is arranged to be held in a first stage by the solenoid 23 in a lowermost position for bread toasting and subsequently in a second stage by the latch member 24 in an intermediate position slightly above the lowermost position for toast warmth keeping. The simultaneous movement of the carrier plate 18 between the intermediate and lowermost positions is utilised to switch on and off the heating element by means of the aforesaid electrical switch. In a simplified construction, the bread cartridge may be arranged to be held by a manually releasable latch alone for both bread toasting and subsequent temperature keeping after the heating element has been switched off.

The invention has been given by way of example only, and various modifications of and/or alterations to the described embodiment may be made by persons skilled in the art without departing from the scope of the invention as specified in the appended claims.

Claims (7)

1. A toaster comprising a casing, a cavity inside the casing, an electrical heating element provided on opposite sides of the cavity, a cartridge provided within the cavity for supporting a slice of bread to be toasted by the heating element inside the cavity, said cartridge being vertically movable between an upper position in which a said slice of bread is partially extending outside the cavity and a lower position in which a said slice of bread is wholly within the cavity and being resiliently biassed towards its upper position by a spring, a timer adapted to determine the toasting time of a said slice of bread, and holding means adapted to hold the cartridge against moving upwards into the upper position before and after completion of the bread toasting, said holding means being manually releasable.

2. A toaster as claimed in claim 1, wherein the holding means is adapted in a first stage to hold the cartridge in the lower position for bread toasting and in a second stage to hold the cartridge in an intermediate position slightly above the lower position for toast temperature keeping.

3. A toaster as claimed in claim 2, wherein the cartridge in the intermediate position is sufficiently low to retain a said slice of bread substantially within the cavity.

4. A toaster as claimed in claim 2 or claim 3, wherein the holding means is provided in the first stage by a solenoid and in the second stage by a latch.

5. A toaster as claimed in any one of claims 1 to 4, incorporating an electrical switch which is arranged to turn on and off the heating element in response to the cartridge moving to and away from the lower position, respectively.

6. A toaster as claimed in any one of the preceding claims, comprising an electronic control circuit including a solid-state timer for determining the toasting time of a said slice of bread.

7. A toaster substantially as hereinbefore described with reference to Figures 1 to 5B of the accompanying drawings.