Summary of the invention
The purpose of the utility model is to overcome above-mentioned shortcoming, provide a kind of can thermostatically controlled electric cooker hot-air system, simple in structure, the dependable performance of the utility model.
The technical scheme that realizes the utility model purpose is, a kind of thermostatically controlled electric cooker hot-air system comprises vortex flow fan, airduct and heater, and vortex flow fan links to each other with airduct, and heater is connected on the airduct, it is characterized in that, said heater is a ptc heater.When the utility model uses, it is installed on the cover assembly of electric cooker, its vortex flow fan communicates with air inlet on the cover assembly; The tail end of airduct communicates with air outlet on the cover assembly.
Steam influences the operate as normal of vortex flow fan in the reverse entering vortex flow fan of air outlet in the pot, and check valve is installed in airduct.
In order further to reach the purpose of heated at constant temperature air, heater design is a pipeline type, comprises the PTC calandria that pipeline is outer with being located at pipeline.
The above-mentioned pipeline PTC calandria outer with being located at pipeline is structure as a whole, and can use die casting aluminium to make, and is placed on the side of pipeline to the PTC heater, forms the heating to pipeline.
Above-mentioned pipeline is arranged to cylindrical shape, can be connected with airduct more easily like this, and sealing more easily.
Because aluminium has good thermal conductivity, when the PTC calandria was worked, on the pipeline around temperature is delivered to rapidly, like this, it was exactly a heater that whole heater is equivalent to, can be all sidedly to the air heat in the pipeline.
The beneficial effect of the utility model is, owing in system, adopt ptc heater, and ptc heater has and self regulates power automatically; Can avoid in to the dry combustion method process of air heat, occurring overheated dry combustion method; And the surface temperature of ptc heater can keep constant temperature in a period of time, and this constant temperature is that PTC is self-regulating; Need not complicated circuitry control, the hot blast that can guarantee the hot-air system supply is a constant temperature.
The specific embodiment
Like Fig. 5, shown in Figure 6; The utility model comprises vortex flow fan 161, airduct 165 and heater 163, and vortex flow fan 161 links to each other with airduct 165, is provided with check valve 162 in the said airduct 165; Heater 163 is connected on the airduct 165, and said heater 163 is ptc heaters.Said heater 163 is designed to pipeline type, comprises pipeline 1632 and the PTC calandria 1631 that is located at outside the pipeline 1632.
The above-mentioned pipeline 1632 PTC calandria 1631 outer with being located at pipeline is structure as a whole, and can use die casting aluminium to make, and is placed on the side of pipeline 1632 to PTC heater 1631, forms the heating to pipeline 1632.Because aluminium has good thermal conductivity, when 1631 work of PTC calandria, on the pipeline 1632 around temperature is delivered to rapidly, like this, it is exactly a heater that whole pipe is equivalent to, can be comprehensively to the air heat in the pipeline.
Above-mentioned pipeline 1632 is arranged to cylindrical shape, can be connected with airduct 165 more easily like this, and sealing more easily.
When the utility model uses;, to shown in Figure 7 it is installed on the cover assembly 100 of electric cooker like Fig. 1, concrete structure is: cover assembly 100 comprises cover 110, inner cap 120, insulation seat board 130, anti-overflow cover plate 140, steam valve 150 and hot-air system; Cover 110 is fixed on inner cap 120 tops; Insulation seat board 130 is fixed on the below of inner cap 120, and anti-overflow cover plate 140 is arranged on the below of insulation seat board 130, contacts with the air of rice 300 tops in the interior pot 200.Steam valve 150 places cover 110 tops; Corresponding steam valve 150 is respectively equipped with the steam venthole on cover 110, inner cap 120, insulation seat board 130, the anti-overflow cover plate 140; In the superfluous water steam of pot in 200 to discharge pot through above-mentioned each steam venthole via steam valve 150 external, prevent that rice from producing to overflow.Also be provided with air outlet 141 on the anti-overflow cover plate 140.
The hot-air system of the utility model comprises vortex flow fan 161, check valve 162, constent temperature heater 163, airduct 165; Vortex flow fan 161 is fixed on the inner cap 120; And be connected with check valve 162, heater 163, airduct 165 successively; The end port of airduct 165 is corresponding with air outlet 141, and hot-air system is inwardly sent into the hot blast additional heat in the pot through air outlet 141.
Owing to use vortex flow fan 161, need and atmosphere, guarantee to have enough gas to get into vortex flow fan 161, can air inlet 141 be set or air inlet be set in perforate on the cover 110 in cover assembly and the hinge connection of stewing between the body assembly.Drain to water on the turbofan because of carelessness when the former possibly cause using, and possibly influence attractive in appearance.The latter is not only safe in utilization, and attractive in appearance, need not to destroy the surperficial uniformity of cover 110.Select for use the hinge connection between cover assembly 100 and pot body assembly that air inlet is set in the present embodiment.
Be illustrated in figure 7 as the wind direction flow schematic diagram when hot-air system is worked in the present embodiment; Air gets into vortex flow fan 161 from air inlet; Behind check valve 162, get into heater 163 and be heated to be the high-temperature hot-air that temperature is higher than 98 ℃ even 120 ℃, then through airduct 165 in air outlet 141 gets into the pot 200, with the water vapour of rice top shift onto discharge in the steam valve 150 stew external; Hot blast constantly flows above rice, and rice is carried out heat supplement.
Because heater 163 is to air heat, whole process is in the state of dry combustion method basically, and uses the advantage of ptc heater to be: ptc heater has self to be regulated power automatically and can prevent overheated dry combustion method.
Simultaneously, PTC can start heating apace, can reach more than 150 degree in general about 30 seconds.
And the surface temperature of ptc heater can keep constant temperature, this constant temperature for a long time in a period of time be that PTC is self-regulating, need not complicated circuitry control, and the hot blast that can guarantee the hot-air system supply is a constant temperature.
In the present embodiment, be not easy to reduce for heat conduction well makes the temperature of the hot blast of the airduct 165 of flowing through, airduct 165 can use copper pipe and heater 163 welding to fix; And wrap heat-preservation cotton on the surface of copper pipe; On the one hand, the heat transfer rate of copper pipe is exceedingly fast, and can guarantee temperature and ptc heater basically identical; On the other hand, heat-preservation cotton can prevent that temperature from reducing.
For the possibility that prevents rice to cook the thin rice gruel that overflows in the process gets into hot-air system, as shown in Figure 7, the airduct 165 that connects air outlet 141 is configured to higher position, and the design of the diameter of air outlet 141 is less.
Because rice also has water at boiling stage; The flowability of dependence water can be delivered to the heat of bottom heater the top of rice; Therefore, hot-air system does not generally use in boiling link or link before, and is preferred; Can be at the after-stage of boiling link, or the cook rice over a slow fire link of boiling link after finishing used.Because after getting into the link of cooking rice over a slow fire, the moisture in the rice obviously reduces, at this moment the temperature of rice bottom becomes higher owing to anhydrous, and the temperature on rice top slowly reduces.Move hot-air system this moment, and heater 163 is opened and heated, and vortex flow fan 161 is opened and carried out wind-guiding, and the hot blast after heater via 163 heating flows into the top of rice endlessly from air outlet 141.In order to reach better effect, the hot blast temperature of air outlet 141 is higher than 98 ℃, even is higher than 120 ℃, can promote the gelatinization that the rice upper surface is good like this, the content of the water vapour of adjustment rice top, and the gold moisture content of assurance rice promotes rice more fragrant.