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Household electronic toaster

Imported: 25 Feb '17 | Published: 06 Aug '02

Alan M. Garber, Paul M. Blankenship, Helmut G. Prager

USPTO - Utility Patents

Abstract

A toaster having an electronic circuit including a chip-on-board ASIC that controls the operation of toaster heating elements and an electromagnet to which relatively high voltage is applied to hold an armature carried by a bread carriage and toaster-operating assembly. The armature is freely suspended from a bread carriage and toaster-operating assembly and accurately guided onto the electromagnet when the bread carriage is lowered. The toaster has a one-piece main frame that includes both a base frame plate and a rear frame plate. Several economies are obtained by virtue the construction of the toaster. A one-piece control support member is mounted on the base frame plate that supports both mechanical and electronic assemblies for controlling the operation of the toaster in predetermined relative positions. The armature can move upward relative to the bread carriage at the end of a toasting cycle if the bread carriage accidentally becomes stuck so that the power switches will assuredly be opened at the end of toasting cycle. A barrier is provided between live electricity and the toaster cover. A crumb tray is provided that may be mounted on the base frame member without the use of tools or additional parts.

Description

Other objects and advantages of this invention will become apparent in view of the following description taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary, exploded, perspective view of parts of a toaster in accordance with this invention, including a base frame including a base frame plate and a frame back or rear plate, an electronic circuit assembly including a printed circuit board, and a control support member on which the printed circuit board is mounted.

FIG. 2 is a fragmentary perspective view similar to FIG.

1 and showing, exploded, a bread support assembly.

FIG. 3 is a fragmentary, exploded perspective view of a printed circuit board terminal clip or edge connector and a support therefor that is part of the control support member of FIGS. 1 and 2.

FIG. 4 is a fragmentary, cross-sectional view taken along section line

4

4 of FIG. 1 of the parts shown in FIG. 3 when assembled together.

FIG. 5 is a fragmentary, cross-sectional view similar to FIG.

3 and in addition shows a printed circuit board.

FIG. 6 is a fragmentary, cross-sectional view showing a locating tab which assists in accurately positioning the control support member on the frame base plate.

FIG. 7 is a fragmentary, cross-sectional view showing a retaining clip which assists in securing the control support member to the frame base plate.

FIG. 8 is a perspective view similar to FIG.

2 and includes, shown exploded, a frame front plate mounted on the main frame.

FIG. 9 is a perspective view similar to FIG.

8 and includes, shown exploded, a center heating element mounted on the base frame plate.

FIG. 10 is an exploded perspective view similar to FIG.

9 and additionally includes, shown exploded, four wire grills pivotally mounted on the frame.

FIG. 11 is a perspective view similar to FIG.

10 and additionally includes, shown exploded, two side heating elements mounted on the frame base plate, a torsion spring confined adjacent the rear frame plate and having ends connected to the rearward ends of two of the wire grills, a frame top plate mounted on the frame front and rear plates, and a rear heat shield mounted on the frame top plate.

FIG. 12 is a perspective view similar to FIG.

11 and additionally includes, shown exploded, electrical bus bars, and a heat shield for the top and sides of the frame.

FIG. 13 is a fragmentary perspective view of the front end of the toaster showing, exploded, components for controlling the operation of the toaster.

FIG. 13A is a perspective view of a carriage control member which is one of the components of FIG. 13, but as viewed from different direction.

FIG. 13B is an enlarged perspective view of a control support member which is another one of the components of FIG.

13.

FIG. 13C is a perspective view of the control support member on the same scale as FIG. 13B, but as viewed more from above the support member than FIG.

13B.

FIG. 13D is a perspective view of the control support member on the same scale as FIGS. 13B and 13C, but as viewed generally from below the support member.

FIG. 14 is a fragmentary perspective view of the electronic circuit assembly of FIG. 1 in accordance with this invention and busses connected to terminals thereof.

FIG. 15 is a fragmentary, vertical cross-sectional view of parts of the toaster illustrated in FIG.

13 and showing the position of parts when the bread support assembly is elevated in its non-toasting, rest position.

FIG. 15A is an enlarged view of the portion of the toaster enclosed within circular section line

15A of FIG.

15.

FIG. 15B is a fragmentary cross-sectional view taken along section line

15B—

15B of FIG.

15A.

FIG. 16 is a fragmentary, vertical cross-sectional view of parts of the toaster illustrated in FIG. 15 but showing the position of parts when the bread support assembly is lowered to its toasting position.

FIG. 17 is a fragmentary, vertical cross-sectional view of parts of the toaster illustrated in FIG. 16 but simplified by removal of parts to show the closure of the power switch.

FIG. 18 is a fragmentary, vertical cross-sectional view of parts of the toaster illustrated in FIG. 15 but illustrating the opening of the power switch while the bread support assembly remains in its lowered position.

FIG. 19 is a perspective view similar to FIG.

12 and additionally includes, shown exploded, a hollow plastic cover that covers the front, rear and top of the frame, the heat shield and the control chamber, and a safety foot attached to the rear frame plate.

FIG. 20 is an exploded perspective view showing in addition to the frame and plastic cover, control knobs and a crumb tray of a complete toaster in accordance with this invention.

FIG. 21 is a bottom plan view of the toaster including fragments of the front end of the crumb tray, the remainder of the crumb tray being shown by phantom lines.

FIG. 22 is a fragmentary, exploded perspective view showing details of connection of the hollow cover to the frame base member.

FIG. 23 is a cross-sectional view taken on section line

23

23 of FIG.

22.

FIG. 24 is a cross-sectional view taken on section line

24

24 of FIG.

22.

FIG. 25 is a diagrammatic, fragmentary exploded, cross-sectional view demonstrating the connection of the crumb tray to the frame base member.

FIG. 26 is a fragmentary, cross-sectional view taken along line

26

26 of FIG.

25 and showing the crumb tray partly assembled onto the frame base member.

FIG. 27 is a fragmentary cross-sectional view similar to FIG. 25 showing the crumb tray pivotally connected to the frame base member.

FIG. 28 is a fragmentary, cross-sectional view taken along line

28

28 of FIG.

27.

FIG. 29 is a fragmentary, cross-sectional view showing the crumb tray pivotally suspended at one end from the frame base plate and clipped at its other end to the frame rear plate.

FIGS. 30 and 31 are rear elevational views of the frame rear member and illustrate the manner in which the torsion spring causes a pivotal movement of the outer wire grills.

FIG. 32 is a diagrammatic and schematic diagram of the control circuit of this invention.

Claims

1. A toaster having a toast control chamber and a toaster control circuit including an electromagnet and a chip-on-board ASIC mounted in said control chamber, said toaster control circuit including circuit components for converting approximately 120 volts AC household current to lower, half wave rectified DC current across the input terminal of the ASIC, and operating said electromagnet with an AC voltage less than 120 volts with a duty cycle of less than 25%.

2. A toaster in accordance with claim 1 wherein said electromagnet is operated with approximately 70 volts AC.

3. A toaster in accordance with claim 2 wherein said ASIC includes a relay driver which controls the duty cycle of the voltage across the electromagnet.