JPS5849730Y2 - heating thermos flask - Google Patents

Description

[Detailed description of the invention] This invention has a heating element that can be connected to an external power supply installed vertically inside the inner bottle surrounded by an outer case, and uses this heating element to heat the liquid in the inner bottle for a long time. Regarding a thermos thermos flask that maintains the liquid inside the inner bottle at a high temperature, the purpose is to provide a thermos flask that is highly safe and consumes little power.

In other words, in this type of heating thermos, when a positive temperature coefficient thermistor is used as the heating element, the electrical resistance value increases as the temperature rises due to heat generation, and when the temperature rises to a certain level, the electrical resistance value reaches the permissible current limit value. Since the energization state will be automatically controlled, it can be expected to be highly effective in preventing breakdowns due to overheating during dry cooking and ensuring safety.

However, commercially available positive temperature coefficient thermistors for heaters all have a small calorific value, so when used as a heating element in the above-mentioned liquid heating heat-insulating container, the temperature of the stored liquid rises slowly, and, for example, Since the temperature range for ON and OFF operation is wide, such as energization is cut off at 120°C, when liquid is contained in the container, the PTC thermistor is cooled by the liquid contained in it,
As a result of maintaining the temperature of the positive temperature coefficient thermistor close to the boiling point of the contained liquid, the energized state remains even if the temperature of the contained liquid becomes higher than necessary, which inevitably results in wasted power consumption.

In order to solve this problem, the applicant of the present application previously devised a heating heat insulating container consisting of a plurality of positive characteristic thermistors and a thermal reed switch in Utility Application No. 55-72839, but In a thermistor, when the current is turned on, a large amount of power flows for several seconds, and it has been found that it is difficult to control the energization of a positive characteristic thermistor with a thermal reed switch.The present invention is a further improvement on this. The above-mentioned problems are solved by combining a thermistor with a bimetal type thermostat or a snap-action quick thermostat that detects the temperature of the liquid in the inner bottle and controls the energization of the positive temperature coefficient thermistor.

Hereinafter, embodiments of the present invention will be described based on the drawings.

Reference numeral 1 is an air pressure-feed type heating thermos flask, which includes an inner bottle 3 surrounded by an outer case 2, an upper lid 5 with a built-in bellows 4, an inner stopper 7 equipped with a suction vibrator, and a dropper hanging inside the inner bottle. A heating element 8 is provided.

9 is the bottom lid, 10 is the heat-resistant mouth rubber, 11 is the drainer, 12
is the discharge pipe connected to the suction vibro of the inner stopper,
The liquid contained in the inner bottle 3 is poured out from a discharge pipe via a suction pipe by a bellows in an upper lid attached to the top of a drainer 11.

The heating element 8 is built in a tubular body 13 made of a material with good thermal conductivity such as stainless steel or aluminum, and includes a plurality of positive temperature coefficient thermistors 14 connected in parallel to each other and a bimetallic thermostat built in the lower end of the tubular body. or a snap-action quick thermostat 15, and the bimetallic thermostat or the snap-action quick thermostat 15 detects the temperature of the stored liquid to control energization to the positive characteristic thermistor 14. It is composed.

When a positive temperature coefficient thermistor enters, it conducts a large current (e.g. 60W or more), so for example, it turns on when the temperature of the contained liquid reaches 80°C and turns off when it reaches the boiling point.
A bimetallic thermostat or a snap-action quick thermostat is used, except for a thermal reed switch with an appropriate ON/OFF temperature range.

16 is a heat insulating separator, 17... is a heat sink made of aluminum, etc., and 18... is a positive temperature coefficient thermistor 1.
A heat-resistant insulating sheet is interposed between 4 and the heat sink 17, 19 is a heat insulating plate, and 20 is a pipe for storing the lead wire 21. The lower end portion is connected to the tubular body 13 by means such as argon welding, and the upper end portion passes through the rubber cap 10.

22 is an upper end portion 22a connected to the mouth rubber 10 and the drainer 1;
1, the lower end is bent horizontally, and the pipe 20 is sandwiched between the bent portion 22b and the vertical portion 22C. The plate (made of SUS, for example) 23 is a waterproof tube made of rubber or synthetic resin that covers the lead wire 21 coming out of the pipe 20.

In the above-mentioned liquid heating thermos thermos, when the content liquid drops to a predetermined temperature, the bimetal type thermostat or snap action type quick thermostat 15 is turned ON, and the positive characteristic thermistor 14 is energized, and the positive characteristic thermistor 14 is turned on. The stored liquid is heated by the heat generated by...

In this case, since a plurality of positive temperature coefficient thermistors 14 are used, the temperature of the contained liquid rises well and quickly rises in temperature.

When the stored liquid rises to a predetermined temperature, the bimetallic thermostat or snap-action quick thermostat is turned off, and the positive temperature coefficient thermistor 14...
The power to... is cut off.

Therefore, while suppressing power consumption by the positive temperature coefficient thermistor 14 to the minimum necessary, the stored liquid can be maintained at a high temperature for a long period of time.

In the above embodiments, the inner container is not limited to the vacuum double-layered bottle as shown in the drawings, but may be, for example, a single-layered bottle surrounded by a heat insulating wall or a metal container.

The present invention has the above-mentioned configuration and uses a plurality of positive temperature coefficient thermistors, so that the temperature of the contained liquid can rise well. In combination with a temperature controller, the power supply to the positive temperature coefficient thermistor is controlled based on the detection result of the temperature of the stored liquid by the bimetal type thermostat or snap action quick thermostat, so the power consumption by the positive temperature coefficient thermistor is suppressed to the necessary minimum. However, the stored liquid can be maintained at a high temperature for a long period of time.

Also, the bimetallic thermostat or snap cushion quick thermostat may be turned off for some reason.
Even assuming the extreme case of connecting to a power source without noticing that the container is empty,
As the temperature rises due to heat generated by the positive temperature coefficient thermistor, the electrical resistance value increases and reaches the energization permissible limit value, and energization is automatically suppressed, preventing accidents caused by overheating and ensuring safety. It is.

Furthermore, the bimetal type thermostat or snap-action quick thermostat can reliably apply a large current that is applied for a few seconds when the positive temperature coefficient thermistor enters.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway vertical sectional view showing an embodiment of the present invention;
The figure is a sectional view taken along the line II--II in FIG. 1. 1... Heating thermos thermos flask, 2... Outer case, 3... Inner bottle, 8... Heating element,
14...Positive characteristic thermistor, 15...
Bimetallic thermostat or snap-action quick thermostat.

Claims (1)

[Scope of utility model registration request] A thermos thermos flask with a heating element vertically placed inside an inner bottle surrounded by an outer case. A heating thermos flask comprising a bimetallic thermostat or a snap-action quick thermostat for controlling.