CN2076377U

CN2076377U - Sounder for boiling water

Info

Publication number: CN2076377U
Application number: CN 90211687
Authority: CN
Inventors: 付鹏鹏
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-03-08
Filing date: 1990-03-08
Publication date: 1991-05-08

Abstract

The utility model relates to a reporting device for boiling water, which can emit the sound when the water boiling. The utility model is that thermistor with negative coefficient and a potentiometer are arranged on a common doorbell circuit. A heat sensitive head made of the thermistor is inserted into the water of a spout; as the rise of the water temperature in a kettle, the value of the resistance of the thermistor becomes small and the electric current of the thermistor is increased to trigger the sound integrated piece to output the electrical signal when the water boiling, and the sound is emitted through a loudspeaker. The utility model has the advantages of convenient operation, high reliability.

Description

Sounder for boiling water

The utility model is the water that can send sound equipment when boiling about a kind of water alarm device that boils.

Hotting plate boiling water needs considerable time, generally can not keep on the kettle limit and wait for that water boils, thereby people wishes to have a kind of water that signal can automatically take place alarm device that boils when water boils.

In view of this, the purpose of this utility model provides a kind of easy to use, and can send the water water of the signal alarm device that boils that boils reliably.

The utility model water of realizing above-mentioned purpose alarm device that boils, comprise a shell (11) and an electronic loop, this electronic loop is thermistor R and potentiometer W who connects a negative coefficient on the doorbell circuit of being made up of power supply, integrated IC of sound equipment, triode BG and loudspeaker Y D.Thermistor R is stretched in outside the shell (11) by the lead that its two ends connect, and seals with non-toxic plastic cover (12) in its end, forms a thermal head that can insert in the kettle mouth water.Concrete circuit connects as follows: 1,4 ends of integrated IC of sound equipment link with the power supply positive and negative electrode respectively, the output 3 of integrated IC of the base stage of triode BG and sound equipment links, the emitter stage and the power cathode of triode link, the end of its colelctor electrode and loudspeaker Y D links, another termination positive source of loudspeaker Y D, the thermistor R of negative coefficient is connected between the trigger end 2 of positive source and integrated IC, its with power cathode between the potentiometer W that connects.

The utility model utilizes the thermistor R characteristic that resistance descends with the rising of temperature of negative coefficient, earlier potentiometer W is transferred to a certain suitable position, when thermal head inserts in the kettle mouth water, along with water is heated, the resistance of thermistor R diminishes, simultaneously, current value in the series circuit increases thereupon, cause the pressure drop of potentiometer two ends also to increase, the current potential of promptly integrated trigger end 2 raises gradually, when arrival water boils temperature, the current potential of trigger point 2 just in time reaches the trigger voltage of integrated IC, IC promptly triggers and by the output 3 output signals of telecommunication, amplifies by triode, and promote the loudspeaker playback.Realize the purpose that water boils and reports.

Because the lead that thermal head is hauled out is longer, extraneous various appliance starting moment produces bigger induced voltage easily on this lead, thereby may make integrated IC produce false triggering, for this reason, the utility model connects a capacitor C between contact 2 and power cathode, so that induced voltage bypasses, avoid producing false triggering.

Adopt the utility model water alarm device that boils,, just can when water boils, send sound equipment reliably, use very convenient as long as thermal head is stretched in the water-in-kettle.

Below in conjunction with description of drawings embodiment of the present utility model.

Fig. 1 is the boil outside drawing of alarm device of present embodiment water.

Fig. 2 is a circuit diagram of the present utility model.

11 is shells among the figure, the 12nd, and plastic sheath, the 13rd, palisade hole

In the present embodiment, shell is an openable cassette shell of bonnet, and the surface has palisade hole (13), is beneficial to sound that loudspeaker send to external diffusion.Integrated of sound equipment can be selected the music integrated chip that contains melody for use, works for integrated during triggering, and loudspeaker are emitted music sound.Present embodiment is selected the NF-12 thermistor for use, resistance is 1N Ω under its normal temperature, its resistance is about 20K Ω when 100 ℃ of boiling points, if integrated trigger voltage is 1.5V, then potentiometer can be transferred to 20K Ω and can trigger integrated and sounding, after potentiometer is once set up, generally do not need to transfer again, can do between summer in winter once to adjust among a small circle.Available approximately 1 year of No. 5 batteries of two joints of packing into during use.

If adopt the thermistor (as NF-51) of temperature measuring type, then this alarm device not only can be used for water and boils and report, and also can be used for the occasion that other needs temperature control, for example the warning of farmers''s grain depot, cellar equitemperature.

Claims

1, the water sound equipment alarm device that boils, comprise a shell (11) and an electronic loop, it is characterized in that, said electronic loop is thermistor R and potentiometer W who connects a negative coefficient on a doorbell circuit of being made up of power supply, integrated 1C of sound equipment, triode BG and loudspeaker Y D, thermistor R is connected between the trigger end 2 of positive source and integrated 1C, potentiometer W of series connection between integrated 1C and power cathode, thermistor R stretches out in outside the shell (11) by the lead that its two ends connected, and its end envelope is with non-toxic plastic cover (12).

2,, it is characterized in that between the trigger end 2 of integrated IC and power cathode, connecting a capacitor C as the described water of the above-mentioned claim 1 sound equipment alarm device that boils.