GB2208786A

GB2208786A - Non boiling-over saucepan

Info

Publication number: GB2208786A
Application number: GB8719903A
Authority: GB
Inventors: Liang Yeh
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-08-24
Filing date: 1987-08-24
Publication date: 1989-04-19
Anticipated expiration: 2007-08-24
Also published as: GB8719903D0; GB2208786B

Abstract

The invention relates to a non boiling-over saucepan, which consists of a saucepan with an enlarged top cylindrical portion and a dome-shaped double lid. The inner lid has a funnel on top and overflow orifices. The height and area of these controls the foam overflow via the space between the two lids and the drain holes back to the saucepan, thus preventing boiling over. <IMAGE>

Description

Non boiling-over Saucepen mis invention refers to a saucepan for use in the kitchen of a normal household for the boiling of foaming liquid, such ac milk, or for the cooking of substances such as nooiles or rice, etc. When heat is applied to the base of any saucepan, the liquid tends to boil over the lid if the temperature is not carefully controlled or reduced immedistely it retches boiling point.

Sometimes it could extinguish the gas flame and cause a gas leak to the room, which might be dangerous and cause explosion.

The invention consists of a cylindrical vessel, the saucepan, (see fig. 1), with an enlarged lip. The diameter of enlargement is approximately (D + 20 mm.), where D is the internal diameter of the saucepan end the depth of the lip is 20 mm. The lid has a dome shape with a cylindrical extension and an orifice, or a number of orifices in the centre throat, the orifice acting like a venturi tube flow meter. The beight of the throat above the water or liquid level in the saucepan controls the boiling over foam heigt according to the following equation, derived from the Bounolli theorem:where flow F is:

where a1, a0 are areas of saucepan and throat of venturi tube (see fig. 2); H1, H0 are heights of monometer reading at inlet and throat due to flow. a1 and hss are heights of inlet and throat or orifices above the water level in the saucepan.

The following conditions are desirable in the design:- (a) H1 - H0 = h0 - h1, i.e. the throat height equals the difference of flow monometer height; or (b) al - aO = a large number or a1 ratio 5.

The invention consists of recirculating the foaming liquid back to the saucepan via an orifice or orifices to the space between the lids. The lid (a) consists of a double skin in a dome shape with a funnel at the end. Rising liquid is allowed to rise up to the top of the funnel of the inner lid and overspill between the two skins from the top orifices and flow back to the saucepan through the loosely fitted inner lid and the enlarged saucepan lip (b) and thus prevents boiling over.

Claims

1. 2 saucepan that can be used to boil liquids without fear of boiling over, whenever heat is applied to the base.

2. The orifice or orifice. control the flow of foaming liouid at the ton of the inner lid.

3. The return Dath of the overflowing foam is on top of the inner lid.

4. The deeply enlarged lip of the saucepan will collect and guide the retnrnerl liouid back to the saucepan through the loosely fitted inner lid.

5. The recirculation of hot steam of the boiling liquid back,to the saucepan will imorove the cookine efficiency.

Amendments to the claims have been filed as follows CLAIMS 1. A saucepan that can be used to boil liquids without fear of boiling over whenever heat is applied to the base.

2. A non boiling-over saucepan as claimed in claim 1 having the orifice or orifices control the flow of foaming liquid at the top of the funnel of the inner lid.

3. A non boiling-over saucepan as claimed in claim 1 or claim 2 wherein the return path of the overflowing foam is on the top surface of the inner lid.

4. A non boiling-over saucepan as claimed in claim 2 wherein the suction provided at the region of turbulant flow of the rising foam allows the liquid to drain back through the drain holes.

5. A non boiling-over saucepan as claimed in claim 1 or claim 2 wherein the deeply enlarged cylindrical lip of the saucepan and the drain holes will collect and guide the returning liquid back to the saucepan through the loosely fitted inner lid.

6. A non boiling-over saucepan as claimed in claim 2 wherein the recirculation of hot steam of the boiling liquid back to the saucepan will improve the cooking efficiency.

7. A non boiling-over saucepan as claimed in any preceding claim wherein the introduction of the double lid will also reduce the heat loss from the top of the saucepan.

8. A non boiling-over saucepan wherein the return flow of foaming liquid is controlled by the height and area of the orifices in the inner lid as shown in Figs. 1 and 2.