NL8502786A - BIMETAL TIME SWITCH. - Google Patents

Description

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Bimetal Time Switch

The invention relates to a bimetal time switch device for electrically heated toasters, which is provided with a bread tray serving as switch-on and switch-off device, consisting of an electrically heated bimetal, which switches off its own heating during a predetermined deflection via a switching lever and after -bending in its initial position loosens the lock on the bread tray, ending the toasting process and a knob for setting the toasting time.

A bimetal time switch device of this kind is known from German patent 21 31 977. In this timer, the shift lever is locked behind a control slide and the bimetal is pressed against the slide by spring force. In the first rest position, the bi-15 metal is heated by an associated heating device.

After a predetermined deflection, the bimetal springs into a recess arranged on the slide and the self-heating of the bimetal is switched off. During cooling, the bimetal pivots back into its starting position and the control slide moves along, whereby the slide releases the shift lever and releases the locking mechanism of the bread slide. The manufacturing costs for this known bimetal timer switch are very high, because it consists of very many parts and during automatic mounting in several places necessitates precise alignment of the parts, because of the manufacturing and mounting tolerances of the numerous parts of the timer switch continuously compensate. In addition, calibration of the timer, that is, its pre-setting after assembly, involves great difficulties.

The object of the invention is to provide a bi-30 metal time switch device, which consists of few parts, which can be easily assembled and whose calibration after assembly does not present any difficulties.

This object is achieved by applying the characterizing features of claim 1.

This ensures that the bimetal and the switching lever provided by the compression spring arranged within the control knob are held freely movable on the stud without additional fastening means. Simultaneously, the compression spring presses on the bimetal and the switching lever with a predetermined force and, as a result, q gives the bimetal the necessary pre-tension, the switching lever the correct switching position and presses the control button with an even pressure against the frame of the timer. By means of the adjusting arm on the switching lever, which is connected to the control knob in a driving manner, the path of the switching lever and thus the desired grating time can be preselected by means of the cutting screw. The bimetal heater is slidably mounted on both sides of the bimetal and is pressed against the bimetal by a spring clip for better heat transfer, so that the bimetal can deflect freely at any time. Failure to switch off the toaster is prevented by a locking device on the switching lever. All parts of the bimetal timer device are connected to the housing of the timer device without additional fasteners, such as screws, rivets and the like, thereby greatly simplifying the mounting and automating the mounting of this timer device.

An exemplary embodiment of the invention is shown in the drawing and will be described in more detail below.

Fig. 1 shows a front view of the bimetal timer device according to the invention;

Fig. 2 shows a top view of the bimetal timer.

Figures 3a to 3c schematically show different switching positions of the timer.

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The bimetal time switching device shown consists of a frame 1 on which a stud 2 and a stop 3 are arranged. A bimetal 4 and a switching lever 5 are mounted for free movement on the stud 2. Both parts are held on the tap 2 by a 2 control knob 6 with a compression spring 7 fitted therein. The button 6 is detachably attached to the frame 1 by means of a snap connection and the compression spring 7 is centered by the stud 2. The bimetal heating device 8 is provided with long holes 9 and is riveted loosely to the bimetal 4. A spring clamp jQ 10 presses the heating device 8 against the bimetal 4 and thus ensures good heat transfer. A switch 11 is also mounted on the switching lever 5, which acts in the event of incorrect adjustment of the adjusting arm 12 and blocks the switching lever 5 on the frame 1.

The toasting time of a toaster is controlled with the aid of the timer device according to the invention. This process is as follows:

With the control knob 6 mounted in the frame 1 of the time switch device with a curve, disc 13 2q, the switching path of the switching lever 5 and the deflection of the bimetal 4 is reduced or increased by means of adjusting screw 14 on the adjusting arm 12 and thereby preselecting the desired roasting time for the product to be roasted. The bread pan (not shown) with the resting lever 15 mounted thereon is moved downwards into the grate position by means of an operating button (not shown).

The rest lever 15 is now with the shift lever 5 and the free end of the shift lever 5 is locked with the bimetal 4. The free end of the bimetal 4 rests against the frame 1, while at the location of the spigot 2 the bimetal 4 rests only against the pivot 16 at 2Q the frame 1 (Figures 1,2 and 3a). The circuits for the bimetal heater 8 and for the grate space heater (not shown) are closed. The cold bimetal 4 and the grating space are heated. The bimetal 4 bends in the arrow direction around the pivot point 16 against the pressure of the spring 7.

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As a result of the deflection, the bimetal 4 first contacts the frame 1 at the location of the stud 2. Due to this lead time of the bimetal 4, that is, the path from the rest position to the abutment against the frame 1, the temperature differences prevailing in the toasting space with cold or preheated toasters are compensated. The bimetal 4 now bends further in the arrow direction and loosens its connection to the switching lever 5 (figure 3b). The switching lever 5 is turned around the spigot 2 by a spring, not shown, by means of the rest lever 15 and stopped against the stop 3. The bimetal heating device 8 is switched off, while the grating space is heated further.

The bimetal 4 cools and pivots back into the starting position, the bimetal 4 releasing the lock between switch lever 5 and stop 3 (figure 3c). The switching lever 15 boom 5 then further rotates about the spigot 2 and releases the resting lever 15 of the bread slide. The toaster space heater is turned off and the bread pan moves up to its initial position, in which the toasted slices of bread can be taken from the toasting area.

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Claims (3)

1. Bimetal time switch device for electrically heated toasters, which are provided with a bread tray serving as switch-on and switch-off device, consisting of an electrically heated bimetal which, with a predetermined deflection by means of a switching lever, has its own heating device. switches off and after bending back into its initial position releases the locking mechanism of the bread tray, ending the toasting process and a control knob for setting the toasting time, characterized in that the bimetal (4) and the switching lever (5) 10 are freely movable mounted on a stud (2), the stud (2) is mounted in the frame (1) of the time switch device, a control knob (6) is mounted concentrically to the stud (2) in the frame (1) and a compression spring (7) is arranged within the control knob (6), which retains the bimetal (4) and the switching lever (5) on the stud (2). Bimetal time switching device according to claim 1, characterized in that an adjusting arm (12) with adjusting screw (14) is arranged on the switching arm (5) and the adjusting arm (12) is connected to the adjusting knob (6) in a driving manner. 20 Bimetal timer device according to claims 1 and 2, characterized in that the bimetal heating device (8) is mounted freely movable on the bimetal (4) and is secured to the bimetal (4) by a spring clamp (10). printed. ^ * 5? ^ A ^. y ^ / 0 O; / "Λ, y · i -". , / - · /