WO2000048496A1

WO2000048496A1 - Electric deep fryer adapted for quick frozen products

Info

Publication number: WO2000048496A1
Application number: PCT/FR2000/000404
Authority: WO
Inventors: Jean-Marc Payen
Original assignee: Seb S.A.
Priority date: 1999-02-19
Filing date: 2000-02-17
Publication date: 2000-08-24
Also published as: FR2789875A1; AU2810200A; FR2789875B1

Abstract

The invention concerns an electric deep fryer comprising a casing (1) forming a housing (2), a vessel (6) mounted removable in said housing, designed to receive a cooking sauce, electrical heating means (4), adjusting means (10), second adjusting means (16) having less thermal inertia than the first adjusting means (10). The invention is characterised in that the adjusting means (10) comprise a bimetal element and are in thermal contact with a heated part of the vessel (6) when said vessel is arranged in the housing (2), the second adjusting means (16) comprise a bimetal element and are in thermal contact with a less hot part of the vessel (6) when said vessel is arranged in the housing (2), control means being provided either to activate alternately the adjusting means (10) or the second adjusting means (16), or either to activate or not the adjusting means (10), or to activate or not the second adjusting means (16).

Description

ELECTRIC FRYER SUITABLE FOR THE USE OF FROZEN PRODUCTS

The present invention relates to the general technical field of domestic electric fryers, and relates more particularly to fryers with removable tanks equipped with electromechanical regulation means.

It is known to produce electric fryers comprising a housing forming a housing designed to receive a removable tank, heating means arranged at the bottom of said housing, and means for regulating the temperature of the cooking bath, preferably at the set temperature. adjustable to adapt the bath temperature to the different types of food to be fried. The electromechanical type regulation means, constituted for example by a bimetallic thermostat, generally have a less expensive construction than the electronic regulation means and are therefore very widespread. The removable bowl is particularly appreciated for the ease of cleaning it provides.

However, electromechanical regulation means of the bimetallic thermostat type with adjustable temperature have certain drawbacks when they are used in a device with a removable tank. First of all, the adjustable thermostat is a thermal coupling difficult to heat because the bimetallic strip is distant from the heated surface and takes the temperature by a rivet in thermal contact with the removable tank. The bimetallic strip is therefore exposed to the influences of ambient temperature. The adjustable thermostat reacts very badly to rapid temperature increases. In addition, the adjustable thermostat is preferably placed in a hot part of the product to obtain good quality cooking results and also to be able to comply with product safety standards in the event of overvoltage, heating dry or with little fat. . As a result, during the first cuts in the thermostat after the appliance has been heated, the temperature of the oil bath is lower than that reached during the following cuts in steady state. The immersion of food in a frying bath causes a drop in the temperature of the frying bath. When frying donuts or breaded fish, the amount of food introduced is usually small compared to the volume of the frying bath, which allows to find the temperature necessary to obtain a crispy coating on the surface of the food at after a few minutes.

When making fries from fresh potatoes, the rise in temperature after the introduction of food is long and makes it difficult to reach the temperature necessary to obtain a crispy coating on the surface of the food, especially when the device is used at its nominal capacity. The fries are soft and unappetizing. This is why cooking in two baths in a basket is generally recommended for fresh fries, the rise of the basket above the frying bath after a first cooking allowing the temperature of the frying bath to rise, and a dive for the second cooking in a frying bath regulated by a thermostat having reached its stabilized speed, making it possible to reach the temperature necessary to obtain very crisp fries.

The cooking of frozen products such as in particular the precooked frozen fries is generally carried out in a single bath, from the first cut of the thermostat. Under these conditions, the temperature of the bath is insufficient and the cooking gives unsatisfactory results, especially if the food is immersed in the frying bath in large quantities from the first cut of the thermostat. The food is fatty and not very crisp. In order to overcome these drawbacks, manufacturers of domestic electric fryers generally recommend when cooking frozen products to reduce the amount of food to be fried compared to cooking fresh food. This provision remains insufficient, however.

It is known from document EP 0 783 861 an electric fryer comprising a removable tank mounted in a housing, associated with electric heating means, first regulation means as well as second means of regulation with less thermal inertia than the first regulation means. The first regulation means are in contact with a side wall of the tank and the second regulation means are in contact with the electrical heating means formed by a heating element fixed under the removable tank. Such a construction has the drawback of subjecting the heating element to regulation during the temperature rise phase. In addition, this document does not indicate how to obtain a sufficient temperature of the cooking bath when switching off one or the other of the thermostats.

The object of the present invention is to present an electric fryer with a removable bowl, which is of economical construction while providing satisfactory cooking results, in particular for cooking frozen products.

The objects assigned to the invention are achieved with an electric fryer comprising a housing forming a housing, a tank mounted removable in said housing, designed to receive a cooking bath, electric heating means, regulation means, second means regulator having less thermal inertia than the first regulating means, because the regulating means comprise a bimetallic element and are in thermal contact with a hot part of the tank when said tank is disposed in the housing, than the second means control comprise a bimetallic element and are in thermal contact with a less hot area of the tank when said tank is arranged in the housing, and that control means are provided either to activate alternatively the regulation means or second means of regulation, either to activate or not the regulation means, or to activate o u not the second means of regulation.

Thus, by selecting one or other of the configurations of the control means, the user can choose the configuration of the appliance most suited to the type of preparation he wishes to carry out, such as the first configuration for fried donuts. or fresh products and the second configuration for deep-frozen products. The arrangement of the latter regulation means in thermal contact with a less hot zone of the tank makes it possible to avoid regulation by stages, in which the temperature of the cooking bath when the regulation means are cut progressively rises with the first regulation cycles. Thus the set temperature of the second regulating means can be calibrated so as to obtain, during their first cut, a temperature in the cooking bath which is higher than that obtained during the first cut of the first regulating means. In addition, thanks to their lower thermal inertia than that of the first regulating means, the second regulating means can be calibrated so as to obtain, when they are first cut, a temperature in the cooking bath which is higher than that obtained during cuts. first means of regulation in steady state. These conditions make it possible to obtain products having a better crispiness, in particular when cooking frozen products in a single bath. Advantageously, a heating indicator is mounted in parallel with the heating means.

This arrangement makes it possible to warn the user of the interruption of the supply of the heating means. In particular, when the control means occupy the second configuration, the user wanting to fry frozen products is informed that the cooking bath has reached an optimal temperature. The user is thus assured of obtaining a sufficiently crisp cooking without having to allow the cooking bath to heat for a long time. The heating indicator can be mounted in parallel with the only heating means, in parallel with part of the heating means if the heating means comprise several elements, or even in parallel with a control element such as a switch or regulation and all or part of the heating means.

Preferably, the first regulation means are formed by a thermostat with adjustable set temperature. Thermostats with adjustable set temperature are certainly inexpensive, but have the disadvantage of having significant dispersions. With a thermostat located in the lower part of the dispersion the temperature of the cooking bath too low does not allow to obtain the quality hoped for with an appliance supposed to be adapted to the different types of food to be cooked. However, the use of second regulation means makes it possible to compensate for faults in thermostats with adjustable set temperature.

Preferably, the second regulation means are formed by a thermostat with a fixed set temperature.

Thermostats with a fixed set temperature have relatively low dispersions and a lower thermal inertia than thermostats with an adjustable set temperature.

According to a first embodiment, the second regulation means are mounted in series with the first regulation means and the control means consist of a control switch mounted in parallel with the first regulation means. Thus, when the control switch is closed, the second regulation means in contact with a less hot zone of the tank manage only the heating means. The user is assured of obtaining a sufficient temperature in the oil bath after the first cut of the second regulating means to obtain a sufficiently crisp preparation. When the control switch is open, the second regulation means can cut off the heating means in place of the first regulation means if, during successive regulations, the temperature in the cooking bath rises to exceed the temperature. for which the second regulation means intervene. This arrangement therefore makes it possible to use first regulating means capable of having cut-off temperatures for which the oil temperature may be slightly higher than the values commonly accepted.

Alternatively, according to a second embodiment, the second regulation means are mounted in series with a control switch constituting the control means, and the first regulation means are mounted in parallel with the second regulation means and the switch of ordered.

Thus, when the switch is closed, the first regulation means and the second regulation means jointly manage the heating means. In the case where the first shutdown of the first regulating means occurs at a temperature of the cooking bath higher than the temperature of said bath for which the shutdown of the second regulating means occurs, this arrangement makes it possible to obtain the oil bath temperature as high as possible during the first cut, in particular when the device has first regulation means located in the upper end of the dispersion of the cut-out temperatures and second regulation means located in the lower end of the dispersion of the shutdown temperatures. These conditions make it possible to obtain products having better crispness during frying in a single bath despite the dispersions of the first and second regulation means. Advantageously then, according to one or other of the embodiments, a control light is mounted in series with a switch coupled to the control switch, the control light and the switch being mounted in parallel with the first regulation means, the second regulation means and the heating means.

This arrangement makes it possible to view the operating mode of the device, the control lamp being lit only when the second regulation means are used, independently of the supply of the heating means.

The heating means can be constituted by an armored heating element mounted in the bottom of the housing. Thus the tank is devoid of heating element. Advantageously then the first regulation means are arranged near a heating part of the shielded heating element. Advantageously also, the second regulation means are arranged near the cold ends of the shielded heating element. These provisions make it possible to obtain a fryer, the construction of which remains economical. The invention will be better understood from the study of exemplary embodiments taken without any limitation being implied and illustrated in the attached figures in which:

- Figure 1 is a side view in section of an embodiment of an apparatus according to the invention, - Figure 2 is a top view of the tank and means for regulating the apparatus shown in figure 1 ,

FIG. 3 is a schematic view of the electrical wiring of a first embodiment of an apparatus according to the invention,

- Figure 4 is a schematic view of the electrical wiring of a second embodiment of an apparatus according to the invention.

Figure 1 shows an electric fryer comprising a housing 1 forming a housing 2 delimited by an inner tank 3, and adapted to receive a removable tank 6. The tank 6 has an upper edge having two diametrically opposite zones 8 provided for gripping said tank. To this end, the housing 1 has a clearance 7 under each of the gripping zones 8 of the tank 6.

The fryer also has heating means 4 formed by an armored heating element 18 mounted on a metal protective plate 19 at the bottom of the housing 2. The bottom of the tank 6 has stamped zones 20 adapted to the shape of the heating element. 18. The tank 6 placed in the housing 1 rests on the heating element 18.

The fryer has a removable cooking basket 9 provided for at least partial immersion of the food to be cooked in a cooking bath. The tank 6 has a maximum cooking level mark 14 and a minimum cooking level mark 15.

The fryer includes regulation means 10 mounted on a plate 11 articulated on the counter tank 3 so as to allow good thermal contact of the regulation means with the tank 6 when said tank is in place in the housing 1. The regulation means 10 are formed by a bimetallic thermostat with adjustable set temperature. The plate 1 1 also carries ultimate thermal safety means 12, formed by a thermal fuse.

According to the invention, the fryer also comprises alternative regulation means 16 and control means for the first regulation means 10 and / or second regulation means 16. These control means are capable of occupying a first configuration in which the first regulation means 10 are activated and / or the second regulation means 16 are deactivated, and a second configuration in which the first regulation means 10 are deactivated and / or the second regulation means 16 are activated.

The second regulation means 16 have a lower thermal inertia than the first regulation means 10, that is to say that they detect an increase or a decrease in temperature more quickly, and are in thermal contact with a less hot zone of the tank 6 when said tank is placed in the housing 2.

As shown in FIG. 1, the second regulation means 16 are formed by a bimetallic thermostat with a fixed set temperature, mounted on a plate 17 articulated on the counter tank 3 so as to allow good thermal contact of the regulation means with the tank 6 when said tank is in place in the housing 1.

This type of thermostat has a lower thermal inertia than the adjustable thermostat used for the first regulation means 10, since in a thermostat with a fixed set temperature the temperature-sensitive element is formed by a bimetallic cup placed against the wall d 'a housing plated on the plate 17, while, in a thermostat with adjustable set temperature, the temperature-sensitive element is usually formed by a bimetallic blade mounted on a rod coming into contact with the plate 11. This results that, for the adjustable thermostat, the volume of material to be heated or cooled before reaching the bimetallic element is greater, which increases the thermal inertia.

In addition, this type of thermostat has a dispersion of a few degrees C, which makes it possible to choose a set temperature of the order of 170 ° C corresponding to a temperature of 210 ° C in the cooking bath while for thermostats with variable set temperature having greater dispersions, greater than 10 ° C, the target temperature in the cooking bath for a thermostat in the middle of the dispersion is 200 ° C.

It will be noted that in FIG. 1 the second regulating means 16 are closer to the bottom of the tank 6 than the first regulating means 10.

Furthermore, FIG. 2 shows that the first regulation means 10 are mounted in a hot zone 30 while the second regulation means 16 are mounted substantially facing the ends 21, 22 of the armored heating element 18 forming a less hot zone 29.

Figure 3 shows an electrical diagram of a first mode of wiring the fryer. The supply circuit for the heating means 4 successively comprises in series a general on-off switch 27, the first regulation means 10, the second regulation means 16, the heating means 4 and the ultimate safety means 12. L control switch 23 is mounted in parallel with the first regulation means 10. The switch 23 forms the control means of the regulation means. Another switch 24 is mounted in series with an indicator light 25 for the second regulation means 16 between the general switch 27 and the ultimate safety means 12, that is to say in parallel with the control switch 23, the first regulation means 10, second regulation means 16 and the heating means 4. A heating indicator 26 is mounted in parallel with the heating means 4.

The operation of the device presented in Figures 1 to 3 is as follows. To make frying from frozen products, the user closes the control switch 23. The switch 24 is then also closed and the control light 25 is on, thus signaling that the second regulation means 16 are activated. At the start of heating, the first regulation means 10 and the second regulation means 16 are in the closed position and the means for 4 heaters are supplied. The heating indicator 26 is on. During the rise in temperature of the cooking bath, the cut-off of the heating means 4 is governed only by the second regulation means 16. Thanks to the low dispersion of the set temperatures and to the high temperature in the oil bath during the first cut by the second regulating means 16 signaled by the extinction of the light 26, the user is sure to immerse the frozen products in a sufficiently hot cooking bath, thus guaranteeing a very crisp preparation.

To carry out other types of cooking in which a temperature of first cut of the regulating means substantially lower than the cut-off temperature in steady state is not troublesome, for example for frying donuts or for making fried potatoes with cooking in two baths, the user opens the control switch 23.

The switch 24 is then also open and the control light 25 is off, thus signaling that the second regulation means 16 are not activated. The user can adjust the set temperature of the first regulation means 10 if necessary.

A second wiring mode of the fryer is shown in FIG. 4. This wiring mode differs from the previous wiring mode in that the second regulation means 16 are connected in series with the control switch 23 and in that the first regulation means 10 are mounted in parallel with the second regulation means 16 and the control switch 23. The control lamp 25 mounted in series with the switch 24 is mounted in parallel with the control switch 23, the second regulating means 16, the first regulating means 10 and the heating means 4.

The operation of this second embodiment is for the user similar to the previous embodiment.

Many improvements can be made to this device within the scope of the claims. As a variant for the second exemplary embodiment, the means for controlling the regulating means may be constituted by an inverter making it possible to supply either the first regulating means or the second regulating means.

As a variant for one or other of the exemplary embodiments, the switch 23 can be replaced by a control device capable of activating or deactivating one of the regulation means, for example by moving the plate. 1 1, or the plate 17, between an active position in which the thermostat 10 or the thermostat 16 are in contact with the tank 6 or near the tank or the heating means, and a deactivated position in which the thermostat 10 or the thermostat 16 is brought into an area beyond the influence of the heating means, or by creating or removing a preferential thermal path between the thermostat 10, or the thermostat 16, on the one hand, and the tank or the means on the other hand. The two plates can for example be mounted on a rocker making it possible to bring one of the thermostats to the active position while the other thermostat is in the deactivated position, and vice versa.

The present invention finds its application in electric fryers with removable vats and in cooking appliances with removable vats provided for frying in an oil bath.

Claims

1. Electric fryer comprising a housing (1) forming a housing (2), a tank (6) removably mounted in said housing, designed to receive a cooking bath, electric heating means (4), regulation means ( 10), second regulation means (16) having less thermal inertia than the first regulation means (10), characterized in that the regulation means (10) comprise a bimetallic element and are in thermal contact with a hot part of the tank (6) when said tank is placed in the housing (2), the second regulation means (16) comprise a bimetallic element and are in thermal contact with a less hot zone of the tank (6) when said tank is disposed in the housing (2), control means being provided either for alternately activating the regulating means (10) or second regulating means (16), or for activating or not activating the regulating means (10), either to activate or not the second regulation means (16).

2. Fryer according to claim 1, characterized in that a heating indicator (26) is mounted in parallel with the heating means (4).

3. Fryer according to one of claims 1 or 2 characterized in that the first regulation means (10) are formed by a thermostat with adjustable set temperature.

4. Fryer according to one of claims 1 to 3 characterized in that the second regulation means (16) are formed by a thermostat with a fixed set point temperature.

5. Fryer according to one of claims 1 to 4, characterized in that the second regulation means (16) are mounted in series with the first regulation means (10) and in that the control means are constituted by a control switch (23) mounted in parallel with the first regulating means (10).

6. Fryer according to one of claims 1 to 4, characterized in that the second regulation means (16) are mounted in series with a control switch (23) constituting the control means and in that the first means regulation (10) are mounted in parallel with the second regulation means (16) and a control switch (23).

7. Fryer according to one of claims 5 or 6, characterized in that a control light (25) is mounted in series with a switch (24) coupled to the control switch (23), and in that the control lamp (25) and the switch (24) are mounted in parallel with the first regulation means (10), the second regulation means (16) and the heating means (4).

8. Fryer according to one of claims 1 to 7 characterized in that the heating means (4) consist of an armored heating element (18) mounted in the bottom of the housing (2).

9. Fryer according to claim 8 characterized in that the first regulating means (10) are arranged near a heating part (30) of the armored heating element (18).

10. Fryer according to one of claims 8 or 9 characterized in that the second regulation means (16) are arranged near the cold ends (21; 22) of the armored heating element (18).