GB2409116A

GB2409116A - Essence burner using resistance detection element to detect water level

Info

Publication number: GB2409116A
Application number: GB0328902A
Authority: GB
Inventors: Chao-Wei Huang
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-12-12
Filing date: 2003-12-12
Publication date: 2005-06-15
Also published as: GB0328902D0

Abstract

An improved structure of a fragrant essence burner is composed of a furnace body 2 having an open topped container 5 for holding water, an electric heating device 3, and a resistance detection element 9 which is preferably located in the bottom wall of the container 5. The resistance detection element 9 detects the presence of water in the container 5 to control the power to the electric heating device 3.

Description

24091 1 6

Description of Invention

"An improved structure of a fragrant essence burner" The present invention relates to a fragrant essence burner, and more particularly relates to a resistance detection element set in the wall of a container of the fragrance essence burner for holding water.

Conventional fragrant essence burners comprise a heated container for holding water and drops of a fragrant essence. The heating of the water and essence causes phytoncide ions to be released into the air of a room in which the fragrant essence burner is placed, so that the people in the room can enjoy a fragrant smell, such as the smell of a forest.

There are two main kinds of heating structure which are habitually used for heating the container of a fragrant essence burner.

The first uses the heat produced by a candle placed under the container, but suffers the disadvantage of the container being easily broken if the flame of the candle is positioned too close to it. Also, the rate of evaporation of the essence from the container into the air gradually decreases due to the temperature of the water reducing as the candle burns down such that the flame moves away from the underside of the container.

The second form of heating structure uses an electrical heating element which, although able to maintain the water in the container at a consistent temperature, can suffer the disadvantage of overheating the container if all of i the water becomes evaporated from the container, and so requires the user to pay close attention to the level of water in the container to avoid overheating and any disastrous consequences.

The present invention seeks to provide an improved fragrant essence burner.

According to the present invention there is provided a fragrant essence burner comprising: a furnace body formed of a cover base and a container, said cover base being of a hollow shell construction, and said container being open topped for containing water and a fragrant essence; an electric heating device located in said cover base; a rectifier circuit configured to convert and drop an alternating input current to a direct current; a stabiliser circuit to receive an input from the rectifier and being configured to filter and stabilise the voltage to be used by a microprocessor and a resistance detection element; said microprocessor being calibrated to detect a given range of resistance rate signals from the resistance detection element that correspond with contact with water; such that in use, when said resistance detection element comes into contact with water, the microprocessor sends an output control signal to control the power source of the electric heating device.

Preferably, said resistance detection element is set in a bottom wall of the container of said furnace body to detect the presence of water in the container.

Conveniently, said cover base of the furnace body can take various shapes and its surface can be covered with various decorative patterns.

The primary purpose of the present invention is to solve the problem of overheating of an electrically heated fragrant essence burner by utilising a resistance detection element preferably located in the bottom wall of the container of the fragrant essence burner. By detecting the difference in resistance rates between water and air, the resistance detection element automatically controls the power to the electrical heating element such that the power is turned off when the water in the container has evaporated and turns the power on when water is in the container.

In order that the invention may be more readily understood, and so that further features thereof may be appreciated, an embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings in which; Figure 1 is a schematic view of a preferred embodiment of the present invention containing a local sectional view; Figure 2 is a block flow diagram of the electrical circuit according to the present invention; and Figure 3 is a circuit diagram of the electrical circuit of the preferred embodiment.

Referring to Figures I, 2 and 3 of the accompanying drawings, a fragrant essence burner 1 according to a preferred embodiment of the present invention is shown composed of a furnace body 2 and an electric heating device 3. The furnace body 2 is formed of an open topped container 5, and a cover base 4 which is of a hollow shell construction. It is to be appreciated that the appearance of the cover base 4 can take the form of various shapes, and its visible surface can be covered with various decorative patterns. The inside of the cover base 4 contains the electrical circuitry and an electric heating element 11 of the electric heating device 3. The container 5 has a resistance detection element set in its bottom wall which is connected to a microprocessor 8 located in the cover base 4. The microprocessor 8 is configured to turn off the power to the electric heating element 11 when the containers 5 run out of water.

With reference to Figure 2 of the accompanying drawings, the electric heating device 3 comprises a rectifier circuit 6, a voltage stabiliser circuit 7, the microprocessor 8, the resistance detection element 9 and an electric heater element driver circuit 10 for controlling the heater element 1 1. An alternating input current is converted and dropped, via the rectifier circuit 6, to a direct current, which is subsequently filtered and stabilised by means of the voltage stabiliser circuit 7 to create a voltage suitable for use by the microprocessor 8 and the resistance detection element 9. The microprocessor 8 is calibrated to detect a given range of resistance rate signals from the resistance detection element 9 that correspond with contact with water. When the resistance detection element 9 comes into contact with water, the microprocessor 8 sends a control signal to the electric heater element driver circuit 10 which, in turn, switches on the electric heater element 11. The container 5 is therefore heated and the fragrant essence evaporates to release phytoncide ions into the air.

However, when the container 5 runs out of water, the resistance measured by the resistance detection element 9 changes to correspond to a value indicative of contact with air, and the microprocessor 8 no longer sends a control signal to the electric heater element driver circuit 10, such that the electric heater element 11 is turned off to prevent the container 5 from overheating and becoming a safety hazard.

In the present specification "comprises" means "includes or consists of" and "comprising" means "including or consisting of".

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

Claims 1. A fragrant essence burner comprising: a furnace body formed of a

cover base and a container, said cover base being of a hollow shell construction, and said container being open topped for containing water and a fragrant essence; an electric heating device located in said cover base; a rectifier circuit configured to convert and drop an alternating input current to a direct current; a stabiliser circuit to receive an input from the rectifier and being configured to filter and stabilise the voltage to be used by a microprocessor and a resistance detection element; said microprocessor being calibrated to detect a given range of resistance rate signals from the resistance detection element that correspond with contact with water; such that in use, when said resistance detection element comes into contact with water, the microprocessor sends an output control signal to control the power source of the electric heating device.
2. A fragrant essence burner according to Claim 1, wherein said resistance detection element is set in a bottom wall of the container of said furnace body to detect the presence of water in the container.
3. A fragrant essence burner according to Claim 1 or Claim 2, wherein said cover base of the furnace body can take various shapes and its surface can be covered with various decorative patterns.
4. A fragrant essence burner substantially and herein before described with reference to and as shown in Figures 1, 2 and 3. t r
5. Any novel feature or combination of features disclosed herein.