GB2602036A

GB2602036A - Recovered-heat-powered lightweight oven

Info

Publication number: GB2602036A
Application number: GB2019840.4A
Authority: GB
Inventors: Burrows William
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-12-15
Filing date: 2020-12-15
Publication date: 2022-06-22
Also published as: GB202108710D0; GB202019840D0; GB2602173A

Abstract

A burner 1 burns fuel such as wood or coal with the hot gases being carried away by a flue 2. A pump, preferably an air pump 4 draws cool air into the system through a cool air intake 3, which may be a pipe or tube. The pump blows air into a heat exchanger 5 located withing the flue. The output from the heat exchanger feeds the oven 6, which may be a sheet metal enclosure capable of being folded for transport or storage. The oven is not air-tight so that air flow is not restricted, and warm air can escape the oven to warm the room in which the oven is located. The heat exchanger may be a coiled tube or pipe.

Description

RECOVERED-HEAT-POWERED LIGHTWEIGHT OVEN

FIELD OF THE INVENTION

This invention relates to an oven which cooperates with a heat exchanger in the exhaust flue of a burner.

REVIEW OF THE ART KNOWN TO THE APPLICANT

Ovens are one of the oldest forms of technology employed by man. Their basic concept, however simply fabricated, is to trap heat in an insulated compartment and to retain it for a long enough duration at a required temperature so that food is cooked. Approximately 50% of the global population still rely on solid fuel burners for cooking and heating, a substantial proportion of which are stoves. The two forms of cooking method offered by stoves are hotplates placed on top of the stove, or ovens that are built into the stove and heated by radiant heat transfer from the point of combustion. They are typically built on that same principal that they use a minimum heat retained in an insulated compartment so that a maximum of that heat achieves and maintains the temperatures required for cooking using as little fuel as possible. There are many configurations of ovens, but all use a substantial amount of material or a configuration of insulation and heat transfer to achieve an even, high temperature over a sustained period of time required for cooking. The substantial amount of material, whether metal, earth, brick or ceramic, are required to withstand the high temperatures of combustion of solid fuels, as well as minimise the loss of heat to minimise fuel consumption.

Various forms of equipment are known which recover the heat from a burner's exhaust flue. Typically, such devices incorporate a cool air intake, an air pump, a heat exchanger in the burner's exhaust flue, and a hot air exhaust. They are used to increase the heating efficiency and effectiveness of wood-burning stoves.

SUMMARY OF THE INVENTION

The object of this invention is to provide an inexpensive and easily transportable oven whose energy source comes from air pumped through a heat exchanger in the flue of a burner. The invention does not require substantial insulation to achieve the sustained heat required for cooking. Instead, the system is lossy, relying on the circulation and replacement of hot air through the system. Removing the requirement for insulation removes the requirement for mass in the oven, which means it can be fitted to any stove of any design, and can be readily fabricated, transported and fitted at low cost.

The invention has particular utility in contexts where it is impractical to deploy solid fuel stoves with the mass required in any other sort of oven. Examples include, but are not limited to, log cabins, boats, temporary homes or tents for displaced persons in emergency or long-term environments.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings: FIG. 1 shows a schematic view of the system.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 shows a schematic of the system, in which a burner 1 burns fuel such as wood or coal. The hot exhaust gases are carried away from the burner 1 by a flue 2. An air pump 4 draws in cool air to the system, preferably from outside the building, through a cool air intake 3, which is preferably embodied as a pipe or tube. The pump 4 blows air into a heat exchanger 5 located within the exhaust flue 2 and arranged such that the exhaust gases are not overly constricted.

Preferably, the heat exchanger 5 is embodied as a coil of steel tube or pipe. The output from the heat exchanger feeds the heated air to an oven 6. Preferably, this is embodied as a simple, inexpensive sheet metal enclosure which can be folded for ease of transport and storage. Preferably the oven 6 is attached to the burner 1 and includes a door so that food can be readily placed in to and taken out of the cavity. Preferably, the sheet metal enclosure is not air tight so that the air flow is not restricted. Advantageously, the warm air that escapes from the oven 1 cavity will help warm the dwelling in which the system is located. Further, the oven 6 need not be insulated since the oven's 6 cavity is constantly replenished with hot air from the heat exchanger 5.

MODIFICATIONS AND FURTHER EMBODIMENTS

Various types of pump may be employed including electric powered, piston or impeller driven pumps. Preferably, the pump is powered by the heat of the burner 1. The preferred arrangement of a heat powered pump is described in the applicant's earlier patent G32017615.2.

Claims

CLAIMSClaim 1: An oven heated by air pumped through a heat exchanger sited to recover heat from the exhaust gases of a stove so that the heated air is pumped into the oven body for circulation through the oven into the room.