DE2632500A1 - Automatic pop-up toaster with accurate toasting time - has electromagnet holding bread holder against compressed spring and electronic timing circuit - Google Patents

Abstract

The pop-up electric toaster contains a bread holder which is pressed down by hand against spring resistance into a lower operating position where it is held by an electromagnet (13) whose coils are subjected to an electric current by actuating. The slide member which is used to press down the bread holder. This movement of the slide member simultaneously switches on an electronic timer (17) which at the end of a predetermined toasting time again breaks the circuit of the electromagnet. Since the pop-up release mechanism is not actuated mechanically but by an electromagnet via the timer a perfect release of the bread holder is always ensured as is the correct toasting time. The slide member and bread holder are preferably connected to a plate of ferromagnetic material such as steel which cooperates with the electromagnet (13).

Description

Toaster with automatic bread ejection mechanism

The invention relates to a toaster with an automatic bread ejection mechanism, consisting of a by hand through a slide against spring resistance in his lower operating position slidable bread support bracket, which after completion of the Roasting process can be moved back into its upper end position by spring force.

In known Tcasters of the aforementioned type, the time control takes place via a bimetal wound with a heating conductor The i3i = etali switches after a the heating coil of the toaster for a certain time. At the end of the subsequent cooling process the ejection mechanism is triggered mechanically.

One of the serious disadvantages of the well-known toaster is the one Mention susceptibility to failure, with the mechanical Release device for the ejection mechanism usually becomes inoperable. Another essential one The disadvantage of the known device is its inaccuracy with regard to compliance of the set roasting time There are deviations from the target value of up to 30 percent. The effect of this is that if the appliance is still cold, the bread is ejected too early On the other hand, if the appliance is hot, ejecting the toasted bread may be too late take place.

The invention is based on the object of a toaster of the initially mentioned to create the type mentioned, which works trouble-free and in which the set release time bi5 to trigger the ejection process regardless of the respective operating time of the device is strictly adhered to.

According to the basic idea of the invention, the problem is solved by that the bread support bracket in its lower operating position by an electromagnet Is retained whose windings are energized by operating the slide are, and that a timer is switched on at the same time by actuating the slide is, which after a predetermined roasting time, the flow circuit of the electromagnet interrupts again.

In the toaster according to the invention, the ejection mechanism is not triggered mechanically, but rather by an electromagnet via an electronic one Timer. Through the electronic timing element in connection with the electromagnet is a trouble-free triggering of the ejection process while strictly adhering to the a predetermined post time guaranteed.

In an advantageous further development of the invention, it is also proposed that that slider and bread holder with a plate made of ferromagnetic material, preferably steel, which cooperates with the electromagnetic.

Another essential feature of the invention is that the timer only interrupts the circuit of the electromagnet and that the heating wire circuit then by moving upwards together with the bread support bracket Slide is interrupted. Correspondingly, by operating the slide the heating wire circuit of the toaster can be closed downwards at the same time.

According to another embodiment of the invention, it is also possible that the timing element after building the predetermined roasting times not only the circuit s of the electromagnet, but also interrupts the heating wire circuit.

In any case, the voltage to supply the power to the Electromagnet and the timer as well as, if necessary.

further electronic elements are tapped from the heating coil of the toaster.

The invention is now based on an embodiment in C-estalt of a circuit diagram illustrated in the drawing and explained in more detail below.

In the circuit diagram shown, 10 denotes the heating coil of the Toasters to which an AC voltage of 220 V is applied. Two in the heating wire circuit arranged switches are with 11 hzw. Numbered 12.

The holding magnet designed as an electromagnetic magnet for the bread support bracket is indicated in the drawing by a coil 13, The right part The circuit diagram also contains the necessary electronic elements of the invention There are in particular transistors 14 and 15 and capacitors 16, 17 to be mentioned.

The electronics (right part of the circuit diagram) only require a small amount Voltage that is tapped off at 18 on heating coil 10. A rectifier 19 converts the voltage, which is initially tapped as alternating voltage, into direct voltage around. The already mentioned capacitor connected in parallel to the rectifier 19 16 assures the smoothing of the rectified voltage.

The circuit described now works as follows.

First of all, the one on the side of the toaster can be moved up and down Slider moved downwards with a mechanical entrainment of the bread support bracket as well as the steel plate connected to this until the steel plate with the Electromagnet comes to rest. When the slide reaches its lowest position, he closes the switches 11 and 12, so that the heating coil 10 of the toaster is under tension. At the same time, the electromagnet 13 is thereby energized supplied, whereupon it forms a magnetic field and thereby the one overlying it Holds the steel plate together with the bread support bracket in the lower position.

The supply of the electromagnet 13 with electricity is made possible by that at the time of triggering the capacitor 17 is discharged and thus the transistor 14 blocks. The transistor 15 is thus lolting.

During the roasting process that is now taking place, the capacitor charges 17 via resistors 20, 21. As soon as the specified voltage at the capacitor 1? is reached, the Transistor 14 is conductive and thus blocks the Transistor 15 * Itierdurch the current flow through the coil of the electromagnet 13 interrupted, so that the magnetic field of the same collapses. The bread support bracket pretensioned springs acting on it can now move it upwards.

At the same time, the slide is taken upwards as a result he opens the switches 11 and 12 and thus ends the roasting process.

The capacitor 17 can then be connected via a designated 22 The diode is discharged again and the toaster is ready for use again.

Exact adherence to the roasting time is ensured by the als-RC combination 17, 20, 21 trained timers in cooperation with the Tranststoren 14, 15 guaranteed. The transistors 1L, 15 each have a further resistor 23 or 24 upstream.

The embodiment according to FIG. 2 differs from the embodiment 1 essentially in that an additional switch 25 is provided which enables the automatic switch-off (right side of the circuit diagram). When the switch 25 is opened, it is therefore possible; the roasting time required in each case controlled by hand.

In addition, in the embodiment according to FIG. 2 the capacitor 16 another resistor 26 connected in parallel.

Patent claims: L e r s e i t e

Claims (10)

Claims 1. Toaster with automatic bread ejection mechanism, consisting of a by hand through a slide against spring resistance in his lower operating position slidable bread support bracket, which after completion of the Roasting process can be moved back into its upper end position by spring force, d a d u r c h e k e n n «e i c n n e that the bread support bracket in its lower The operating position is held by an electromagnet (13) whose windings be energized by actuating the slide, and that by actuation of the slide at the same time a timer (17, 20, 21) is switched on, which after a predetermined roasting time, the circuit of the electromagnet again interrupts. 2. Toaster according to claim 1, d a d u r c h g e k e n n -z e i c h n e t, that by actuating the slide, the heating wire circuit at the same time (10) of the toaster is closed. 3. Toaster according to claim l or 2, d a d u r c h g e -k e o n n z E i c h n e t that slider and bread support bracket with a plate made of ferromagnetic Material, preferably steel, are connected, which, with the electromagnet (13) cooperates. k. Toaster according to claim 1, 2 or 3, d a d l r c c h g e k e n n n z e i c h n e t that the timing element (17) (20) (21) only the circuit of the electromagnetic magnet (i3) interrupts and that the heating wire circuit (10) is connected by the together with the office support bracket upward moving slider is interrupted. 5. Toaster according to claim 1 or 3, d a d u r c h g e k e n n z e 1 n h n e: t that the timing element (17) (20) (21) after the predetermined roasting time has elapsed not only the circuit of the electromagnet (13), but also the heating wire circuit (10) interrupts. 6. Toester according to one or more of the preceding claims, d a d u r c h g e k e n n n z e i c h n e that the voltage for the energy supply of the Electromagnet (13) and the timing element (17) (20) (21) and other electronic ones Elements (e.g. 14, 15) tapped from the pickling winding (10) of the toaster (at 18) will, 7. Toaster according to claim 6, d a d u r c h g e k e n n -e e i c h n e t that the voltage tapped at the heating coil (10) via a rectifier (19) equilibrated and smoothed a first capacitor (16) connected in parallel to this will. 8. Toaster according to claim 7, d a d u r c h g e k e n n -z e i c h n e t that the timing element has an RC coupling connected in parallel to the first capacitor (16) (17) (20) (21) is used, which controls a first transistor (14) and daX the first Transistor such a second connected in series with the electromagnetic magnet (13) Transistor (15) is assigned that the second transistor through the first transistor, as soon as this becomes conductive, it is blocked. 9. Toaster according to one or more of the preceding claims d a d u r c h g e k e n n z e 1 c h n e t that additional a manually operated switch to arbitrary Interruption of the electric circuit of the electromagnet (13) is present. 10. Toaster according to claim 9, d a d u r c h g e k n n -z e i c h n e t that the additional switch for arbitrary interruption of the circuit of the electromagnet (13) is arranged in or on the slide.