Electric stove

Abstract

The claimed electric heating device is intended for heating and steam generation in steam rooms and saunas, and provides for stable high-temperature heating of heat-retaining elements. An electric sto

Description

[0001] ELECTRIC OVEN

[0002] FIELD OF TECHNOLOGY TO WHICH THE INVENTION RELATES

[0003] The device relates to the field of electrical engineering, in particular, to the design of an electric heating device intended for heating and steam generation, and can be used to equip baths and saunas.

[0004] LEVEL OF TECHNOLOGY

[0005] Electric heating devices for baths and saunas are known "Premiera Rusa 220V with a closed heater", Premiera Rusa 380V with a closed heater" (Electric heating devices for baths and saunas, Operation manual URL: https: / / vvd.su / pdi705.03.22" vs 0 btosh рг gaga a 0 c s- : pres yrti. df. Electric stoves for baths and saunas / Premiera stoves / Premiera Rusa stove 220V (with a closed heater) URL: za.krytoj---kamenkoj#prettyPhotod, each of which consists of a block of tubular electric heaters (TENs) and an external enclosure. At the bottom of the electric heating device there is a terminal block for connecting it to the control panel. Chipped stone (gabrodiabase, talc chlorite or quartzite) is placed inside the electric heating device. The heat-accumulating capacity of electric heating devices is ensured by the presence of: open and closed heaters in the devices. To humidify the air in the steam room, a “glass” with a heat accumulator is located inside the closed heater. The small volume of the closed heater ensures rapid heating of the heat-accumulating elements, but, at the same time, their rapid cooling in the steam generation mode. An additional volume of steam must be obtained from the stones in the open heater.Providing the required steam generation mode leads to the temperature of the steam room itself starting to decrease due to the decrease in the temperature of the heat-accumulating elements during steam generation. The process of steam generation and maintaining the temperature in the steam room is discrete, which leads to a decrease in the quality of the steam produced, or a decrease in the temperature of the steam room, which, in turn, also affects the quality of steam generation.

[0006] Also known is the device "Electric stove for a Russian bath and a method for maintaining the air temperature with an electric stove in the steam room of the bath" (RU2738678, published: 12 / 15 / 2020 Bulletin No. 35), which includes an insulated stove body, electric heaters, heat-accumulating elements, a temperature sensor for the heat-accumulating elements. In this case, the insulated stove body is made with a sealed base and side walls fixed to it. Electric heaters are placed in the insulated stove body between the heat-accumulating elements, with each electric heater made in the form of a heat-conducting flask in which a tubular electric heater is fixed. The heat-accumulating elements are made in the form of steel rods.The insulated body of the furnace has a built-in ventilation duct for air supply, containing a fan with a check valve, designed to supply air through air gaps between the heat-accumulating elements, while the fan with a check valve, the temperature sensor of the heat-accumulating elements and the electric heater are designed with the possibility of connection to the control unit. Due to the fan blowing over the heat-accumulating elements and electric heaters, hot air is supplied to the steam room, while the electric heaters are cooled at this time, and the temperature of the heat-accumulating elements decreases. To obtain steam directly from the heat-accumulating elements, their additional heating is required, therefore, more time is needed to heat the steam room and the heat-accumulating elements. The process of steam generation and maintaining the temperature in the steam room is discrete.

[0007] A device known as "Electric stove for a steam room of a bathhouse" (RU 2756610, published 04.10.2021 Bulletin No. 28) comprises a housing with at least one heating element installed: in an inner housing with an outlet. An air shell is formed between the housing and the inner housing, communicating via air ducts with the discharge outlet of the fan and with the cavity of the inner housing; the heating element and the fan are connected to a control unit connected to at least one sensor measuring the temperature in the steam room. At least one ventilation hole is made in the inner housing, a temperature sensor is installed, connected to the control unit. A temperature sensor is installed between the housing and the inner housing, connected to the control unit.The air duct connected to the fan discharge outlet is made with an outlet opening, behind which there is a control unit made in the form of a damper and connected to the control unit. The steam generator is a separate container from the main device with an outlet for steam, with an inlet pipeline for the constant supply of water evaporated by tubular electric heaters (TEN) located inside the steam generator, the level of which is set by a float valve also in a separate container with a non-hermetic lid connected by a branch pipe to the water supply system. The air temperature in the steam room is regulated by a fan and a damper, and the steam generator used to produce water vapor is used only to maintain the optimal ratio of temperature and humidity in the steam room, preventing the creation of finely dispersed steam, which can only be obtained at a temperature of at least 500 ° C.The design of the device consists of several components with moving and rubbing surfaces and additional equipment (float valve, damper, fan), which often fail and require repair and maintenance.

[0008] A device known is "Electric Sauna Furnace with Steam Generation" (SE500509C2, US5054105A, DE4005793A1), in which at least one electric resistor for heating the sauna room is located and inside which, on top of the resistor, stove stones can be placed, and an evaporator in the form of a steam tank with water, a steam furnace, where at least one electric resistor for heating water to a state of steam is located, and thermostatic regulators including a sensor located near the outer surface of the steam tank and responding to an increase in temperature from a predetermined temperature. Nearby: a water supply tank can be located with the evaporator, or water comes directly from the water supply network. The evaporator is additionally connected to a rough steam outlet and a pipe near the upper part of the sauna furnace.The disadvantages are the complex algorithm of the device, which does not allow for stability and continuity of the temperature regime and humidification regime of the steam room, while the design of the evaporator does not allow for the production of finely dispersed steam.

[0009] The device "Electric stove for saunas" RU 2057998 is known, taken as a prototype, containing a firebox with electric heaters and a chamber communicating with it with a heat-accumulating load. The firebox body is formed by a base with a screen and a casing installed coaxially above it, the walls of which form open-bottomed through channels, covered with a lid on top, in the center of which a flexible air-permeable heat-resistant mesh is fixed, placed in the cavity of the firebox, and on its sides there are louvered windows. In the cavity of the firebox, vertical glasses made of heat-conducting material are placed in an U-shape, inside which electric heaters are installed on insulators. The screen prevents the spread of heat to the sides and collects the heat flow for entering the heat-accumulating chamber by a convection flow. The loading chamber of the device is made in the form of a flexible mesh made of heat-resistant material, the sealed glass is made of heat-resistant steel with a wall thickness of at least 3 mm, the glass is partially protected by blinds.In this device, only the body of the glass, the temperature of which is 450° C, can be irrigated with water. Infrared radiation is transmitted to the bodies of the glasses, and from them it spreads throughout the volume of the firebox. In the internal cavity of the firebox, a convection air flow arises, coming from below in the channel between the bodies of the base and the screen, which fills the firebox. Infrared radiation partially heats the screen and is reflected from it back to the center of the firebox, simultaneously summing up with other heat flows. The temperature of the rising air flow in the center of the firebox acquires a maximum value. The high-temperature air flow, focused in the central part, rises and encounters obstacles: the chamber, which it bypasses from the side, and through the channels between the heat-accumulating load penetrates into the chamber and uniformly heats it (the heat-accumulating load) to a high temperature. The air, having partially given off heat, comes out and heats the steam room.The less heated flow in the firebox rises at the wall of the screen, which also partially heats up and gives off heat to the channel between the screen and the casing. As a result, self-regulating convection heat flows arise in the channels, which heat the steam room of the bath. When the temperature in the steam room reaches 125° C, the electric furnace automatically switches off and remains switched off until the temperature drops to 110° C, and then switches on again, etc. The cycle is repeated. When the heat-accumulating load reaches the required temperature (380° C), water is supplied to it in portions to produce steam. The process of steam generation to produce dry steam is short-lived. When the required temperature is reached in the room, the heat-accumulating load may not have time to warm up to the temperature required to produce dry steam.After feeding water to the heat-accumulating load to obtain steam, it will be necessary to restore the temperature required for steam formation, which will lead to an excessive increase in the air temperature in the room. The process of steam formation and maintaining the temperature in the steam room is discrete. Hard infrared radiation in the room can cause burns. The device is offered for effective production of dry steam in a steam room of 12 m. 3 . Exceeding the specified intervals worsens the efficiency of use, as it leads to the production of raw steam or excessive growth of the power of heaters while simultaneously increasing the danger.

[0010] DISCLOSURE OF THE ESSENCE OF THE INVENTION

[0011] The task that this technical solution is aimed at solving is to improve the consumer properties of the device by providing high-temperature heating of the heat-accumulating elements of the closed heater while simultaneously maintaining the required constant air temperature in the steam room by the convector to obtain the best steam generation mode.

[0012] The result is achieved by the claimed device, which is a frame structure with a metal body in the form of a regular vertically oriented parallelepiped, in the cover of which a bowl of an external decorative heater with heat-accumulating elements made of natural stones and a convection grate through which hot air enters the room are mounted. The bowl of the external heater is made in the form of a container with walls located at an angle to the center of the base of the bowl, from below, to the hole in the bottom of the bowl, a round section branch pipe is welded. Inside the frame structure with a metal body, a module of a closed heater with heat-accumulating elements for creating fine steam is installed and, located under it, a convector heater. A box of a convection channel of rectangular cross-section is adjacent to the rear wall of the device body, its upper part entering under the convection grate of the device cover.On the outside, the device has a composite decorative lining in the form of tinted heat-resistant glass panels or, for example, decorative panels made of stone or brick, which also serves as additional protection against infrared radiation from the device.

[0013] For example, polished or split natural stones can be used as heat-accumulating elements in open and closed saunas. In addition to natural stones, artificial heat-accumulating elements can be used in closed saunas, for example, metal ingots of various geometric shapes that meet the requirements for resistance to temperature changes, heat capacity and health safety.

[0014] The closed heater module is a metal body in the form of a regular, vertically oriented parallelepiped with double walls, a bottom and a cover, between which a high-temperature heat-insulating material is laid, at least 25 mm thick, for example, ceramic fiber, the physical and chemical characteristics of which ensure the lightness, strength and wear resistance of such a structure under high-temperature operating conditions of the device, protect the external space from infrared radiation and not waste heat on heating the steam room itself. The cover of the closed heater fits tightly to the walls of the heater and has an opening through which a branch pipe from the external heater passes, and to which a structure made of profile pipes is attached from below, for example, of a square section, with a number of small holes or slots in the lower part of the horizontally located pipes of the structure.The structure made of profile pipes can additionally be supported, for example, by brackets fixed to the inside of the heater walls. At least two heating elements with a total power of at least 3 kW and a thermocouple sensor for monitoring the temperature in the closed heater are installed on the bottom of the heater.

[0015] To release finely dispersed steam, a number of small, horizontally elongated, oval slits with a nozzle above them are made in the lid of the closed heater, from which, when water hits the heat-accumulating elements of the closed heater, steam, through the convection channel box, exits through the convection grate of the device into the steam room. The nozzle opening is turned towards the convection channel. Through the branch pipe of the bowl of the external heater, water enters the structure of the closed heater's profile pipes and then, through the openings in the profile pipes, onto the heat-accumulating elements of the closed heater.

[0016] In a closed heater, you can place heat-accumulating elements weighing from 25 to 30 kg, which can be heated by heating elements located inside the heater up to 500° C, without losing heat to heat the room. Due to the tight connection of the lid with the heater body, excess pressure is formed inside the heater, which helps to heat up the steam and generate fine steam. At a temperature of stones of at least 500° C, water instantly turns into fine, so-called "light" steam, allowing a person to breathe freely and easily in the steam room and which does not create clouds of water-saturated steam in the room itself. If you do not maintain a high temperature in a closed heater, then, when saturated steam is formed, some of the water remains in a droplet state. Such steam is conventionally called "raw" or "heavy", it leads to a large amount of condensation and increases the feeling of heat in the steam room.The body in such a steam room becomes wet without having time to sweat, and breathing becomes intermittent and heavy. The same effect will occur in the case of insufficient heating of the steam room itself at the moment when the heat-accumulating elements of the closed heater are already sufficiently heated to a temperature of at least 500° C to create steam.

[0017] The convector heater is a structure in the form of a rectangular parallelepiped with two oppositely located double walls, between which a heat-insulating material is laid, for example, ceramic fiber with a thickness of at least 25 mm, on the inner side of the walls an electrically insulating material is laid, for example, a mica plate with a thickness of at least 0.5 mm, the front wall of the convector heater has convection openings in the form of a horizontal grate for the flow of air from the steam room into the convector for heating it, the opposite rear side of the convector heater is open and tightly inserted into the opening of the convection channel box, through which the air, heated to the required temperature, enters through the convection grate into the steam room.To protect the opposite wall of the convection channel box from infrared radiation from the inside, a protective screen is installed on it, opposite the convection convector, for example, in the form of an additional metal sheet. Several heating spirals are installed inside the convector heater depending on the required power of the device and the size of the heated room, but not less than 3 kW, which are connected to the electronic control unit through a terminal module fixed to the outside of the frame structure. Heating elements and a thermocouple temperature sensor located in a closed heater are also connected to the terminal module.

[0018] The control unit is a panel on which the information output device and temperature control relay units are located. Data from the temperature sensor located in the closed heater and from the air sensor in the steam room are sent to the control unit and displayed on the display; if necessary, the air temperature is regulated using the relay.

[0019] The design of the device allows for heating of the steam room without reducing the temperature of steam generation in the closed heater and, conversely, ensuring the required temperature of steam generation in the closed heater does not lead to a decrease in the temperature in the steam room due to the independent high-temperature heating of the heat-accumulating elements of the closed heater while simultaneously maintaining the required air temperature in the steam room by the convector of the device to obtain finely dispersed steam.

[0020] The technical result is the creation of a device design that ensures a stable high-temperature heating mode for the heat-accumulating elements of a closed heater while simultaneously maintaining the required air temperature in the steam room by the device's convector to obtain the best steam generation mode.

[0021] BRIEF DESCRIPTION OF DRAWINGS

[0022] The essence of the technical solution is explained by the following drawings. Fig. 1 - General view of the device without facing panels Fig. 2 - Closed heater module with removed front and side walls without heat-accumulating elements

[0023] Fig.3 - Convector heater

[0024] Fig.4 Convection channel box

[0025] Fig.5 - Rear view of the device with the convection channel box panel Fig.6 - Side view of the device with the convection channel

[0026] Fig.7 - Construction of a closed heater made of profile pipes

[0027] As shown in Fig. 1, the device is a frame structure with a metal body: 1 in the form of a regular, vertically oriented parallelepiped, fixed on a base 2. On the cover 3 of the device there is a bowl of the external heater 4 and a convection grate 5. Inside the frame structure of the device, on a metal panel 6 fixed on the frame structure 1, a module of the closed heater 7 is installed, and under the metal panel 6 a convector heater 8 is located. The walls of the metal body 1 are made in such a way that they do not cover the area where the convector heater 8 is located. On the rear wall of the metal body of the frame structure 1 of the device, a convection channel 9 is fixed, which is closed from above by a convection grate 5 of the cover 3. The bowl of the external heater 4 is made in the form of a container with walls located at an angle to the center of the base of the bowl, to the bottom of which a branch pipe 10 is welded from below.The closed heater module 7 and the convector heater 8 of the device are connected to the electronic control unit 11 via the terminal module 12. For example, an air sensor 13 for monitoring the temperature in the steam room can also be connected to the electronic control unit.

[0028] As shown in Fig. 2, the closed heater module 7 is a metal body, the side walls and the bottom of which are assembled from panels 14 with double walls, between which heat-insulating material 15 is laid. The cover 16 of the closed heater 7 is also insulated from the inside with heat-insulating material 15. A structure of profile pipes 17 with a number of parallel slots or small holes in the downward-facing part of the horizontally located pipes of the structure is inserted into the branch pipe 10, passing inside the closed heater 7 through an opening in the cover 16. The structure of profile pipes 17 can additionally rest, for example, on brackets 18, fixed on the inner side of the walls of the closed heater module 7.For the release of finely dispersed steam, a number of small, horizontally elongated, oval slots with a nozzle 19 above them, turned towards the box of the convection channel 9, through which steam enters through the convection grate 5 of the cover 3 of the device into the steam room, are made in the cover 16 of the closed heater 7. At least two heating elements 20 in the form of spirals made of conductive materials with a total power of at least 3 kW are installed on the bottom of the closed heater 7, in metal boxes with stiffening ribs at the corners and inside the box, filled with an electrically insulating filler, for example, electrical periclase, and a thermocouple temperature sensor 21.

[0029] As shown in Fig. 3, the convector heater 8 is a structure in the form of a rectangular parallelepiped with two side double walls 22, between which heat-insulating material 23 is laid, on the inner side of the walls an electrically insulating material 24 is additionally laid, to which heating elements 25 are attached, the front wall of the convector heater 8 has convection openings in the form of a horizontal grid 26 for the flow of air into the convector, the oppositely located part of the convector heater 8 is open and tightly inserted into the opening on the rear panel of the convection channel 9, slightly extending beyond its limits. The heating elements 25 of the convector heater 8 are connected to the electronic control unit 11 via the terminal module 12, secured externally to the frame structure 1. The heating elements 25 and the thermocouple temperature sensor 21, located in the closed heater 7, are also connected to the terminal module 12.

[0030] The design of the convection channel 9 and its location on the device are illustrated in Fig. 4, Fig. 5, Fig. 6. The box of the convection channel 9, shown in Fig. 4, consists of a rear panel 27 with small side edges bent at a right angle and a rectangular opening in its lower part for the size of the convector heater 8, which, as shown in Fig. 5, is attached to the frame structure of the device in such a way that the upper edge of the panel 27 of the convection channel 9 is flush with the cover 16 of the closed heater 7, and a panel 28, also with side edges bent at a right angle, which is attached to the panel 27, and from above, as shown in Fig. 6, goes under the cover 3 of the device. The box of the convection channel 9 has a bottom formed by the bent lower edges of the panels 27, 28. Between the convection channel box 9 and the metal body of the frame structure 1, heat-insulating material 29 is laid.A protective screen 30 is installed on the lower inner side of the panel 28, opposite the open part of the convector heater 8.

[0031] Fig. 7 shows one of the possible design options for uniformly distributing water flowing through the branch pipe 10 into the structure of profile pipes 17 to the heat-accumulating elements of the closed heater 7 through a series of parallel slots or small openings in the downward-facing part of the horizontally located pipes of the structure. The upper part of the structure of profile pipes 17 is made in the form of a small length of a round tube welded to the main structure, which enters the branch pipe 10. IMPLEMENTATION OF THE INVENTION

[0032] The device operates as follows. The device is installed in the steam room and connected to the electronic control unit 1 1 via the terminal module 12, fixed in the lower side part of the frame structure 1. The control unit 11 allows selecting automatic operating modes of the device, monitoring and regulating the temperature in the closed heater module 7 using the thermocouple sensor 21, in the steam room via the air sensor 13 connected to the control unit 1 1, and limiting the operating time of the device.

[0033] The module of the closed heater 7 and the bowl of the external heater 4 are filled with heat-accumulating material and are tightly closed with a lid 16. The tight fit of the lid 16 to the module of the closed heater 7 can be additionally ensured, for example, by a heat-resistant cord laid along the inner perimeter of the lid.

[0034] When power is supplied from the control unit by closing the control power contacts of the relay on the spirals of conductive materials of the heating elements 20 of the closed heater 7, they are heated to a temperature of at least 700° C, which, in turn, through the electrical insulating material placed in the box of the heating elements 20, heat the walls of the box. The heat-accumulating material inside the closed heater is heated to a temperature of at least 500° C. The thermocouple temperature sensor 21, located inside the module of the closed heater 7, allows monitoring the heating temperature of the heat-accumulating elements.

[0035] Independent heating of the room occurs as follows. When power is supplied from the control unit by closing the control power contacts of the relay on the spirals of conductive materials of the heating elements 25 of the convector heater 8, they are heated to a temperature of at least 250° C. The outside air, entering through the convection openings of the grille 26 into the convector heater 8, passes through the heated spirals of the heating elements 25, heats up and, already hot, enters the steam room through the convection channel 9 and the openings of the convection grille 5. The air heating temperature in the convector heater can reach a temperature of up to 200° C. As soon as the air temperature in the room heats up to the required temperature in the steam room, which, as a rule, is no more than 110° C, the sensor 13 switches off the heating of the convector.

[0036] To obtain finely dispersed steam, water is fed into the bowl of the external heater 4, water through the hole in the bowl base enters through the steam pipe 10 into the structure of profile pipes and, through the holes in the lower part of the horizontally located pipes of the structure 17, is evenly distributed over the heat-accumulating materials of the closed heater 7 of the device. Due to the tight connection of the cover 16 to the body: closed heater 7, excess pressure is formed inside the heater, which contributes to the additional heating of steam and the generation of finely dispersed steam. Water, getting on the heat-accumulating elements of the closed heater 7 heated to a high temperature, surrounded by the heated internal walls of the closed heater, explodes with a characteristic pop.Hot steam with drops of water rushes upwards, but, in a closed space, colliding with the hot surface of the inner walls of the closed heater, it is additionally heated by them and the air between the heat-accumulating elements, thereby producing repeated "micro-flaps". Due to the high temperature of heating of the heat-accumulating elements of the closed heater 7, water particles become smaller and smaller and so-called light, finely dispersed steam is formed. Finely dispersed steam, being under pressure inside the closed heater 7, flies out at high speed through the nozzle 19, located on the cover 16 of the closed heater 7, and then, through the convection channel 9 and the holes of the convection grate 5 of the device, enters the steam room, thereby creating, in addition, a special characteristic sound, reminiscent of the "sound of a blizzard". The nozzle opening is turned towards the convection channel.

[0037] The design of the device allows for a stable high-temperature heating mode for the heat-accumulating elements of a closed heater while simultaneously maintaining the required air temperature in the steam room by the convector of the device, which in turn allows for the best steam generation mode. The quality of the steam produced in a closed heater allows a person to breathe freely and easily in the steam room, independent maintenance of the temperature mode for heating the room and creating steam does not allow for the creation of clouds of water-saturated steam in the steam room itself:

Claims

The invention claims an electric stove comprising a housing with a lid, inside which electric heating coils are placed in a convector heater with heat-insulating walls and a heater module with heat-accumulating elements, a convection channel, characterized in that the convection channel housing is fixed to the rear wall of the stove housing, the convector heater inside the housing is located under a closed heater, electrical insulating material is fixed to the inside of the walls of the convector heater, the front wall of the convector heater has convection openings, the rear part of the convector heater enters the opening of the rear panel of the convection channel box, on the cover of the stove housing there is a bowl of the outer heater and a convection grate against which the opening of the convection channel box rests, the opening at the bottom of the bowl of the outer heater has a branch pipe from the inside, the body of the closed heater with the lid is protected by heat-insulating material,Inside the closed heater, there is a structure of profile pipes with a number of holes, insulated heating elements, a temperature sensor, in the lid of the closed heater there is a row of slots with a nozzle above them, turned towards the convection channel box, the upper edge of the rear panel of the convection channel box is made flush with the lid of the closed heater. The electric stove according to claim 1, characterized in that the thickness of the thermal insulation material of the convector heater and the closed heater is at least 25 mm. The electric stove according to claim 1, characterized in that the thickness of the electrical insulation material of the convector heater is at least 0.5 mm. 17 SUBSTITUTE SHEET (RULE 26) The electric stove according to claim 1, characterized in that the total power of the heating coils of the convector heater is at least 3 kW. The electric stove according to claim 1, characterized in that an air sensor is connected to the electronic control unit. The electric stove according to claim 1, characterized in that the structure of the closed heater profile pipes rests on brackets fixed to the inner side of the walls of the closed heater module. The electric stove according to claim 1, characterized in that the total power of the heating elements of the closed heater is at least 3 kW. The electric stove according to claim 1, characterized in that in the closed heater the heating elements are placed in metal boxes with stiffeners at the corners and inside the box, filled with electrical insulating filler. The electric stove according to claim 1, characterized in that the closed heater module and the convector heater are connected to the electronic control unit. The electric stove according to claim1, characterized in that a protective screen is installed in the convection duct box opposite the convector heater. The electric oven according to claim 1, characterized in that heat-insulating material is placed between the rear panel of the convection duct box and the housing. SUBSTITUTE SHEET (RULE 26)

Images