BG4311U1 - Convector heater - Google Patents

Abstract

The utility model relates to a convector heater comprising two radiators (1 and 2), an intermediate radiator (3) located between two pairs of electrodes (4 and 5). The intermediate radiator (3) is a monolithic body in which vertical circular or square openings (6) are formed. The radiators are in contact with the electrodes (4 and 5) and are insulated therefrom by a corresponding electrical insulating layer (8a, 8b, 8c, 8d). Between the electrodes (4 and 5) there are thermistors (7) connected in series with a positive electrical resistance coefficient. The use of an intermediate heat radiator and the construction of all heat radiators (monolithic body with vertical openings) increases the heat radiation area, thereby increasing the heat transfer coefficient. The inclusion of an additional pair of electrodes increases the power of the appliance, thus reducing its gauge.

Description

Field of application

The utility model refers to a convector heater converting electrical energy into thermal energy, which can be used for heating domestic and industrial premises, transport cabins, railway train compartments, etc.

Prior art

A convector heater is known [1], which consists of two metal radiators, each of which has a heat-radiating surface and a base. A pair of electrodes is located between the bases of the radiators, and between the electrodes - serially connected thermoresistors made of a material with a positive coefficient of electrical resistance. The heat-radiating surfaces of the radiators are equipped with ribs or needle-shaped elements. The base of each radiator contacts one of the electrodes through an electrically insulating layer. The construction is covered by clamps or screw connections to ensure reliable contact between the electrodes and the terminals of the thermistors.

Technical nature of the utility model

The purpose of the useful model is to increase the heat transfer coefficient of the convector heater and to optimize its mode of operation.

This goal is achieved with a convector heater containing two heat-radiating radiators and a pair of electrodes, between which are serially connected thermistors with a positive coefficient of electrical resistance. Each radiator has a heat-radiating surface and a flat surface - the base. The base of the first heat-radiating radiator contacts one of the electrodes through an electrically insulating layer. The device is characterized by the fact that it contains a second pair of electrodes, between which are located serially connected thermistors with a positive coefficient of electrical resistance, and an intermediate radiator located between the two pairs of electrodes. The intermediate radiator is a monolithic body with two flat surfaces, in which vertical openings are formed. One surface of the intermediate radiator is in contact with the second electrode of the first pair of electrodes through an electrical insulating layer, and its other surface - through an electrical insulating layer with one electrode of the second pair of electrodes, the other electrode of which is in contact with the base of the second radiator through an electrical insulating layer.

In one embodiment, the heat-radiating surfaces of the two heat-radiating radiators are provided with fins or needle-like elements.

In a preferred embodiment, each of the heat emitting radiators is a monolithic body with uniformly shaped vertical openings. The holes can be round or square.

It is preferable that the holes of the intermediate radiator have a round or square section.

It is expedient for the electrically insulating layers to be mica or electrically insulating thermally conductive tape.

The advantages of the convector heater, according to the utility model, are the increased heat transfer coefficient and the optimized mode of operation.

Explanation of the attached figures

Figure 1 schematically shows the front panel of the convector heater, according to the utility model;

figure 2 is a cross-section of the convector heater along A-A.

Examples of implementation of the utility model

Figure 1 illustrates the principle of operation of the heater according to the utility model. The natural convection of the air is used, in which the heated air rises upwards, and the cold air from the environment is directed to the lower part of the unit. The body is made of sheet metal. Its lower part may be open or have openings for free passage of air.

The convector heater, according to fig. 2, includes two heat-radiating radiators 1 and 2, an intermediate radiator 3 and two pairs of electrodes 4 and 5 with electrode designations 4a, 4b and 5a, 5b respectively, connected to a power source (not shown). Each heat-radiating radiator has a heat-radiating surface and a flat surface - base, respectively 1a and 1b, and 2a and 2b. The intermediate radiator 3 is a monolithic body with two flat surfaces 3a and 3b, in which vertical openings 6 are formed. In fig. The 2 holes are round in cross-section, but can also be square. Between the electrodes of each pair of electrodes 4 and 5, thermistors 7, which are made of semiconductor ceramic material with a positive coefficient of electrical resistance, are located in series connected to them.

The base 1b of the heat emitting radiator 1 contacts one of the electrodes of the first pair of electrodes 4 - 4a through the electrical insulating layer 8a. One flat surface 3a of the intermediate radiator 3 contacts through the electrical insulating layer 8b with the second electrode 4b of the first pair of electrodes 4, and its other flat surface 3b - through the electrical insulating layer 8c - with one electrode 5a of the second pair of electrodes 5. The other electrode 5b of the second a pair of electrodes 5 contacts the base 2b of the second heat emitting radiator 2 through the electrical insulation layer 8d.

In the preferred embodiment of the utility model shown in FIG. 2, each of the heat emitting radiators 1 and 2 is implemented as a monolithic body in which vertical openings 9 are formed. The openings can be of round or square cross-section. With this design, the best results are obtained in terms of the heat transfer coefficient and the electrical energy consumption is reduced.

Versions are possible, in which the heat-radiating surfaces of the radiators 1 and 2 are equipped with ribs or elements with a needle-like shape.

The device is equipped with a thermostat (not shown) to maintain a set temperature, which is connected in the circuit of the thermistors.

The electrically insulating layer may be mica or electrically insulating thermally conductive tape, for example, mecanite.

The operation of the convection heater is as follows.

When an electric voltage is applied to the electrodes 4 and 5, a current flows through the thermistor 7, as a result of which they heat up. Their electrical resistance increases, which leads to an increase in the released heat, which is transmitted to the radiators. The air in openings 6 and 9 of the three radiators is heated to the required temperature and, thanks to convection, rises up through them, cools in the environment and descends. Cold air enters openings 6 and 9 through the lower part of the unit, heats up and rises up, etc. In this way, through the continuous circulation, the air in the room is warmed.

The heating control of the thermistor is carried out by the thermoregulator, through which the desired temperature is set in advance. After reaching the desired temperature, it switches off.

The advantages of the convector heater are as follows.

With the use of an intermediate radiator with the specified design, the area of heat radiation increases, which increases the heat transfer coefficient. The design of the heat radiating radiators in the preferred embodiment further enhances heat transfer. With this form of all radiators, chosen experimentally, the effect of convection and maximum release of the generated heat is optimally achieved. This optimizes the operating mode of the device. The inclusion of an additional pair of electrodes increases its power, thereby reducing its size.

Thanks to the additional radiator and the qualities of the ceramic thermistor, a reduction in the consumption of electrical energy is achieved compared to the known device while maintaining the same set temperature.

Other advantages are the reduced risk of fires, as well as the possibility of use in damp rooms.

Claims (1)

A convective heating device containing two heat-radiating radiators (1, 2) and a pair of electrodes (4a, 4b), between which are serially connected thermistor (7) with a positive coefficient of electrical resistance, and each radiator has a heat-radiating surface (1a, 2a) and a flat surface - base (1b, 2b), wherein the base (1b) of the first heat-radiating radiator (1) contacts one of the electrodes (4a) through an electrical insulating layer (8a), characterized in that the device contains a second pair of electrodes (5), between which are located serially connected thermistors (7) with a positive electrical resistance coefficient, and an intermediate radiator (3) located between the two pairs of electrodes (4, 5), where the intermediate radiator (3) is a monolithic body with two flat surfaces (3a, 3b), in which body vertical openings (6) are formed, with one surface (3a) of the intermediate radiator (3) contacting the second electrode (4b) of the first pair of electrodes (4) through an electrical insulating layer (8b), and its other surface (3b) - through an electrical insulating layer (8c) with one electrode (5a) of the second pair of electrodes (5), the other electrode (5b) of which contacts the base (2b) of the second radiator (2) through an electrical insulating layer (8g)