Indian Patents. 194044:A COOKING UTENSIL COMPRISING A HEATING SURFACE, A SENSOR FOR MEASURING THE TEMPERATURE THEREOF AND A MEANS FOR DISPLAYING THIS TEMPERATURE

Title of Invention	A COOKING UTENSIL COMPRISING A HEATING SURFACE, A SENSOR FOR MEASURING THE TEMPERATURE THEREOF AND A MEANS FOR DISPLAYING THIS TEMPERATURE
Abstract	The sensor (2) for measuring the temperature of the utensil is an infrared sensor arranged at a location of the utensil such that it can receive the infrared radiation (4) emitted by the heating surface (1), the said sensor (2) being connected to an electronic circuit (5) capable of converting the variation in the infrared radiation caused by the heating of the utensil into an electrical signal.

Full Text	- 1A - The present invention relates to a cooking utensil comprising a heating surface, a sensor for measuring the temperature thereof and means for displaying this temperature. The invention is intended for any cooking utensil comprising a heating surface heated by a heating source external to the utensil or built into it. The invention is intended particularly, but not necessarily, for the following utensils: frying pans, saucepans, high-sided frying pans, cooking pots, meat grills, waffle irons, barbecues, raclette makers, pressure cookers, deep Eryers and so forth. In particular, a cooking utensil comprising a temperature display means built into the utensil handle is known from American Patent 5 441 344. The temperature sensor is a thermocouple placed in the base of the utensil and connected to an electronic circuit and a temperature display screen built into the handle. The problem with this cooking utensil is that the incorporation of the thermocouple in the base of the utensil is complicated and expensive. In addition, the electrical connections between the probe, the electronic circuit and the temperature display screen pose problems because of the moisture to which the utensil is exposed, especially during washing and repetitive thermal cycles. The object of the present invention is to solve the problems of the aforesaid device. Accordingly, the present invention provides a - 2 - cooking utensil comprising a heating surface, a sensor for measuring the temperature of said heating surface and means for displaying this temperature, wherein said sensor is an infrared sensor, said infrared sensor being arranged at a location of said utensil such that it can receive infrared radiation emitted by said heating surface, said sensor being connected to an electronic circuit capable of converting the variation in the infrared radiation caused by the heating of said utensil into an electrical signal. This sensor senses directly, or after reflection, the infrared radiation emitted by the heating surface and requires no modification to the cooking utensil to build it into the latter. The wavelength of the infrared radiation emitted by the heating surface varies as a function of temperature. All that is required therefore is to convert this variation in the wavelength into an electrical signal and to convert the latter into a value indicating the temperature. Preferably, the said infrared sensor is fixed to the handle of the utensil, particularly when the latter is a frying pan, a saucepan or the like. Preferably also, the infrared sensor is placed in a closed housing projecting from the upward-oriented face of the handle. This housing protects the sensor from the surrounding environment and in particular from water. The fact that it projects above the upward-oriented face of the handle enables it to be exposed to the infrared radiation emitted by the cooking surface. In an advantageous version of the invention, the said housing is fixed detachably to the handle of the utensil. It is thus possible to remove the housing before placing the utensil in a dishwasher. Other features and advantages of the invention will also appear in the description which follows. - 3 – BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS In the appended drawings provided by way of non-restrictive examples: - Figure 1 is a sectional view of a frying pan fitted with a temperature sensor in accordance with the invention; - Figure 2 is a sectional view of the housing containing the temperature sensor which senses the infrared radiation after reflection; - Figure 3 is a sectional view of the housing containing the temperature sensor which senses the infrared radiation directly; and - Figure 4 is a view similar to Figure 1 showing that the housing is detachable from the handle. In the embodiment shown in Figure 1, the cooking utensil, a frying pan, comprises a cooking surface 1, a sensor 2 for measuring the temperature of this surface 1, and means 3 for displaying this temperature. In accordance with the invention, the sensor 2 for measuring the temperature is an infrared sensor arranged at a location of the utensil such that it can receive the infrared radiation 4 emitted by the cooking surface 1. The infrared sensor 2 is connected {see Figure 2) to an electronic circuit 5 capable of transforming the wavelength of the infrared radiation 4 into an electrical signal which is a function of the temperature. In the example illustrated by Figure 1, the infrared sensor 2 is fixed to the handle 6 of the utensil. In addition, the infrared sensor 2 is placed in a closed housing 7 projecting above the upward-oriented face 6a of the handle 6. As indicated in Figure 2, the housing 7 includes a face 8 oriented towards the cooking surface 1 and comprising a window 9 transparent to the infrared radiation 4. An elliptical reflective surface 10 is - 4 – situated in the path of the infrared radiation 1 that has passed through the window 9. The latter is situated roughly on one F1 of the foci of the elliptical reflective surface 10. The entrance face 2a of the infrared sensor 2 is situated on the other focus F2 of the elliptical reflective surface 10. It can also be seen in Figure 2 that the housing 7 includes, on the opposite side from the face 8 oriented towards the cooking surface 1, a transparent face 10a behind which is a screen 3 for displaying the temperature. In addition, the housing 7 contains a support 11 that carries the infrared sensor 2, the elliptical reflective surface 10, the electrical circuit 5 for converting the wavelength of the infrared radiation, the temperature display screen 3 and an electric battery 12 for powering the said electronic circuit. In the embodiment shown in Figure 3, the housing 7 includes a face 8 oriented towards the cooking surface 1 and comprising a window 9 transparent to the infrared radiation 4, and a parabolic reflective surface 10b situated in the path of the infrared radiation 4 that has passed through the window 9. The entrance face 2a of the infrared sensor 2 is situated on the focus F3 of the said parabolic surface 10b. The parabolic surface 10b thus senses the infrared radiation directly and concentrates it on the sensor 2 situated on the focus F3 of this parabolic surface 10b. Preferably, the said housing 7 {see Figure 4) is fixed detachably to the handle 6 of the utensil, thus making it possible for the housing 7 to be removed before the frying pan is placed in a dishwasher. From the above description it will be clear that the utensil according to the invention has the following main advantages: - the temperature sensor requires neither any - 5 – modification of the frying pan for its incorporation, nor electrical connections sensitive to moisture; - the housing 7 protects the sensor and its electrical accessories from moisture and can be detached before washing to avoid any risk of damage; - a single housing that can be adapted to a whole range of utensils. If the cooking utensil comprises an electrical resistor for heating its heating surface, the sensor 2 can be connected to means for regulating the heating power of the electrical resistor in order to maintain the heating surface at an approximately constant temperature. Such means are very familiar to those skilled in the art and do not need to be described or illustrated in the drawings. Of course, the invention is not limited to the example of a cooking utensil as described, but can be applied to any utensil or cooking appliance having a heating surface, as indicated in the introduction of the present description. - 6 -WE CLAIM: 1. Cooking utensil comprising a heating surface (1), a sensor (2) for measuring the temperature of said heating surface (I) and means (3) for displaying this temperature, wherein said sensor (2) is an infrared sensor (2), said infrared sensor (2) being arranged at a location of said utensil such that it can receive infrared radiation (4) emitted by said heating surface (1), said sensor (2) being connected to an electronic circuit (5) capable of converting the variation in the infrared radiation (4) caused by the heating of said utensil into an electrical signal. 2. Utensil as claimed in claim 1, wherein said infrared sensor (2) is fixed to a handle (6) of said utensil. 3. Utensil as claimed in claim 2, wherein said infrared sensor (2) is placed in a closed housing (7) , said housing (7) projecting above an upward-oriented face (6a) of said handle (6). 4. Utensil as claimed in claim 3, wherein said housing (7) comprises a face (8) oriented towards said heating surface (1) and comprising a window (9) transparent to the infrared radiation (4) , and a reflective surface (10,10b) situated in the path of the infrared radiation (4) that has passed through said window (9). 5. Utensil as claimed in claim 4, wherein said reflective surface (10) is an elliptical reflective surface (10) having two foci (F1,F2), said window (9) being situated on a first focus (Fa) and said sensor (2) having an entrance face (2a) situated on the other focus (F2) . 6. Utensil as claimed in claim 4, wherein said reflective surface (10) is a parabolic reflective - 7 – surface (10b) having one focus (F3), said sensor (2) having an entrance face (2a) situated on said focus (F3) . 7. Utensil as claimed in claim 4, wherein said housing (7) comprises, on the opposite side from said face (8) oriented towards said heating surface (1) , a transparent face (10a) behind which is a screen (3) for displaying the temperature. 8. Utensil as claimed in claim 4, wherein said housing (7) contains a support (11) that carries said sensor (2), said reflective surface (10,10b), said electronic circuit (5) , said means (3) for displaying the temperature, and an electric battery (12) for powering said electronic circuit (5) . 9. Utensil as claimed in claim 3, wherein said housing (7) is fixed detachably to said handle (6) of said utensil. 10. Utensil as claimed in claim 1, wherein it comprises an electrical resistor for heating said heating surface (1) , said sensor (2) being connected to means for regulating the heating power of said resistor and the temperature of said heating surface (1) . 11. A cooking utensil, substantially as herein described particularly with reference to and as illustrated in the accompanying drawings. The sensor (2) for measuring the temperature of the utensil is an infrared sensor arranged at a location of the utensil such that it can receive the infrared radiation (4) emitted by the heating surface (1), the said sensor (2) being connected to an electronic circuit (5) capable of converting the variation in the infrared radiation caused by the heating of the utensil into an electrical signal.

Full Text

- 1A -
The present invention relates to a cooking utensil comprising a heating surface, a sensor for measuring the temperature thereof and means for displaying this temperature.
The invention is intended for any cooking utensil comprising a heating surface heated by a heating source external to the utensil or built into it.
The invention is intended particularly, but not necessarily, for the following utensils: frying pans, saucepans, high-sided frying pans, cooking pots, meat grills, waffle irons, barbecues, raclette makers, pressure cookers, deep Eryers and so forth.
In particular, a cooking utensil comprising a temperature display means built into the utensil handle is known from American Patent 5 441 344.
The temperature sensor is a thermocouple placed in the base of the utensil and connected to an electronic circuit and a temperature display screen built into the handle.
The problem with this cooking utensil is that the incorporation of the thermocouple in the base of the utensil is complicated and expensive. In addition, the electrical connections between the probe, the electronic circuit and the temperature display screen pose problems because of the moisture to which the utensil is exposed, especially during washing and repetitive thermal cycles.
The object of the present invention is to solve the problems of the aforesaid device.
Accordingly, the present invention provides a

- 2 -
cooking utensil comprising a heating surface, a sensor for measuring the temperature of said heating surface and means for displaying this temperature, wherein said sensor is an infrared sensor, said infrared sensor being arranged at a location of said utensil such that it can receive infrared radiation emitted by said heating surface, said sensor being connected to an electronic circuit capable of converting the variation in the infrared radiation caused by the heating of said utensil into an electrical signal.
This sensor senses directly, or after reflection, the infrared radiation emitted by the heating surface and requires no modification to the cooking utensil to build it into the latter.
The wavelength of the infrared radiation emitted by the heating surface varies as a function of temperature. All that is required therefore is to convert this variation in the wavelength into an electrical signal and to convert the latter into a value indicating the temperature.
Preferably, the said infrared sensor is fixed to the handle of the utensil, particularly when the latter is a frying pan, a saucepan or the like.
Preferably also, the infrared sensor is placed in a closed housing projecting from the upward-oriented face of the handle.
This housing protects the sensor from the surrounding environment and in particular from water. The fact that it projects above the upward-oriented face of the handle enables it to be exposed to the infrared radiation emitted by the cooking surface.
In an advantageous version of the invention, the said housing is fixed detachably to the handle of the utensil. It is thus possible to remove the housing before placing the utensil in a dishwasher.
Other features and advantages of the invention will also appear in the description which follows.

- 3 –
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
In the appended drawings provided by way of non-restrictive examples:
- Figure 1 is a sectional view of a frying pan fitted with a temperature sensor in accordance with the invention;
- Figure 2 is a sectional view of the housing containing the temperature sensor which senses the infrared radiation after reflection;
- Figure 3 is a sectional view of the housing containing the temperature sensor which senses the infrared radiation directly; and
- Figure 4 is a view similar to Figure 1 showing that the housing is detachable from the handle.
In the embodiment shown in Figure 1, the cooking utensil, a frying pan, comprises a cooking surface 1, a sensor 2 for measuring the temperature of this surface 1, and means 3 for displaying this temperature.
In accordance with the invention, the sensor 2 for measuring the temperature is an infrared sensor arranged at a location of the utensil such that it can receive the infrared radiation 4 emitted by the cooking surface 1.
The infrared sensor 2 is connected {see Figure 2) to an electronic circuit 5 capable of transforming the wavelength of the infrared radiation 4 into an electrical signal which is a function of the temperature.
In the example illustrated by Figure 1, the infrared sensor 2 is fixed to the handle 6 of the utensil.
In addition, the infrared sensor 2 is placed in a closed housing 7 projecting above the upward-oriented face 6a of the handle 6.
As indicated in Figure 2, the housing 7 includes a face 8 oriented towards the cooking surface 1 and comprising a window 9 transparent to the infrared radiation 4. An elliptical reflective surface 10 is

- 4 –
situated in the path of the infrared radiation 1 that has passed through the window 9. The latter is situated roughly on one F1 of the foci of the elliptical reflective surface 10. The entrance face 2a of the infrared sensor 2 is situated on the other focus F2 of the elliptical reflective surface 10.
It can also be seen in Figure 2 that the housing 7 includes, on the opposite side from the face 8 oriented towards the cooking surface 1, a transparent face 10a behind which is a screen 3 for displaying the temperature.
In addition, the housing 7 contains a support 11 that carries the infrared sensor 2, the elliptical reflective surface 10, the electrical circuit 5 for converting the wavelength of the infrared radiation, the temperature display screen 3 and an electric battery 12 for powering the said electronic circuit.
In the embodiment shown in Figure 3, the housing 7 includes a face 8 oriented towards the cooking surface 1 and comprising a window 9 transparent to the infrared radiation 4, and a parabolic reflective surface 10b situated in the path of the infrared radiation 4 that has passed through the window 9.
The entrance face 2a of the infrared sensor 2 is situated on the focus F3 of the said parabolic surface 10b.
The parabolic surface 10b thus senses the infrared radiation directly and concentrates it on the sensor 2 situated on the focus F3 of this parabolic surface 10b.
Preferably, the said housing 7 {see Figure 4) is fixed detachably to the handle 6 of the utensil, thus making it possible for the housing 7 to be removed before the frying pan is placed in a dishwasher.
From the above description it will be clear that the utensil according to the invention has the following main advantages:
- the temperature sensor requires neither any

- 5 –
modification of the frying pan for its incorporation, nor electrical connections sensitive to moisture;
- the housing 7 protects the sensor and its electrical accessories from moisture and can be detached before washing to avoid any risk of damage;
- a single housing that can be adapted to a whole range of utensils.
If the cooking utensil comprises an electrical resistor for heating its heating surface, the sensor 2 can be connected to means for regulating the heating power of the electrical resistor in order to maintain the heating surface at an approximately constant temperature.
Such means are very familiar to those skilled in the art and do not need to be described or illustrated in the drawings.
Of course, the invention is not limited to the example of a cooking utensil as described, but can be applied to any utensil or cooking appliance having a heating surface, as indicated in the introduction of the present description.

- 6 -WE CLAIM:
1. Cooking utensil comprising a heating surface (1), a sensor (2) for measuring the temperature of said heating surface (I) and means (3) for displaying this temperature, wherein said sensor (2) is an infrared sensor (2), said infrared sensor (2) being arranged at a location of said utensil such that it can receive infrared radiation (4) emitted by said heating surface (1), said sensor (2) being connected to an electronic circuit (5) capable of converting the variation in the infrared radiation (4) caused by the heating of said utensil into an electrical signal.
2. Utensil as claimed in claim 1, wherein said infrared sensor (2) is fixed to a handle (6) of said utensil.
3. Utensil as claimed in claim 2, wherein said infrared sensor (2) is placed in a closed housing (7) , said housing (7) projecting above an upward-oriented face (6a) of said handle (6).
4. Utensil as claimed in claim 3, wherein said housing
(7) comprises a face (8) oriented towards said heating surface (1) and comprising a window (9) transparent to the infrared radiation (4) , and a reflective surface (10,10b) situated in the path of the infrared radiation (4) that has passed through said window (9).
5. Utensil as claimed in claim 4, wherein said
reflective surface (10) is an elliptical reflective
surface (10) having two foci (F1,F2), said window (9)
being situated on a first focus (Fa) and said sensor
(2) having an entrance face (2a) situated on the other focus (F2) .
6. Utensil as claimed in claim 4, wherein said
reflective surface (10) is a parabolic reflective

- 7 –
surface (10b) having one focus (F3), said sensor (2)
having an entrance face (2a) situated on said focus
(F3) .
7. Utensil as claimed in claim 4, wherein said housing
(7) comprises, on the opposite side from said face
(8) oriented towards said heating surface (1) , a transparent face (10a) behind which is a screen (3) for displaying the temperature.

8. Utensil as claimed in claim 4, wherein said housing (7) contains a support (11) that carries said sensor (2), said reflective surface (10,10b), said electronic circuit (5) , said means (3) for displaying the temperature, and an electric battery (12) for powering said electronic circuit (5) .
9. Utensil as claimed in claim 3, wherein said housing (7) is fixed detachably to said handle (6) of said utensil.
10. Utensil as claimed in claim 1, wherein it comprises an electrical resistor for heating said heating surface (1) , said sensor (2) being connected to means for regulating the heating power of said resistor and the temperature of said heating surface
(1) .
11. A cooking utensil, substantially as herein described
particularly with reference to and as illustrated in
the accompanying drawings.

The sensor (2) for measuring the temperature of the utensil is an infrared sensor arranged at a location of the utensil such that it can receive the infrared radiation (4) emitted by the heating surface (1), the said sensor (2) being connected to an electronic circuit (5) capable of converting the variation in the infrared radiation caused by the heating of the utensil into an electrical signal.

Documents:

00015-cal-1999-abstract.pdf

00015-cal-1999-claims.pdf

00015-cal-1999-correspondence.pdf

00015-cal-1999-description(complete).pdf

00015-cal-1999-drawings.pdf

00015-cal-1999-form-1.pdf

00015-cal-1999-form-2.pdf

00015-cal-1999-form-3-1.1.pdf

00015-cal-1999-form-3.pdf

00015-cal-1999-form-5.pdf

00015-cal-1999-gpa.pdf

00015-cal-1999-priority document(others).pdf

00015-cal-1999-priority document.pdf

15-CAL-1999-CORRESPONDENCE-1.1.pdf

15-CAL-1999-CORRESPONDENCE.pdf

15-CAL-1999-FORM 27.pdf

15-CAL-1999-PA.pdf

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Patent Number

194044

Indian Patent Application Number

15/CAL/1999

PG Journal Number

30/2009

Publication Date

24-Jul-2009

Grant Date

13-Apr-2005

Date of Filing

11-Jan-1999

Name of Patentee

SEB S.A.

Applicant Address

LES 4M, CHEMIN DU PETIT BOIS, 69130, ECULLY

Inventors:

#	Inventor's Name	Inventor's Address
1	DAVID ADAMCZEWSKI	CHARANSONNEX, 74150, MASSINGY

PCT International Classification Number

A47J27/00,G01K1/02

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	9800733	1998-01-23	France