Electrically driven heater for vapour heated consumer

Abstract

The invention relates to an electrically driven heater (1) for a vapour-heated consumer (2), comprising a fluid storage container (3) for receiving a fluid, a mould (5) heated by the fluid, and a laying line (4) for the fluid storage container (3) and the mould (5) heated by the fluid, and a temperature sensor (17) and / or a pressure sensor, and a heating means (19) which interacts thermally with the fluid and which can be operated by means of electrical energy.

Description

Technical Field

[0001] The invention relates to an electrically driven heater for a consumer heated by steam, the electrically driven heater comprising: a fluid storage container for receiving the fluid, a pipeline between the fluid storage container and a mold heated by the fluid, a temperature sensor and / or a pressure sensor, and a heating device that is in thermal interaction with the fluid and can be operated by means of electrical energy.

[0002] The invention also relates to a method for operating such an electrically driven heater. Background Art

[0003] An electrically driven heater with a fluid-heated mold is known, for example for heating tire presses. The tire presses have a central boiler for generating steam, which is usually connected to several tire presses by means of pipelines. It has proven disadvantageous to use one boiler for several steam-heated consumers or even just one boiler for several heating chambers of a tire press, for example, since this results in a high outlay in the pipelines. The pipelines also have to be maintained, with flexible pipelines having a higher maintenance outlay. The pipelines require a considerable amount of structural space and therefore restrict the design of the steam-heated consumers. In addition, the pipelines cause energy losses during operation due to their heat dissipation and thus lead to reduced efficiency.

[0004] Furthermore, decentralized electrically driven heaters are known, which, however, are not provided for heating molds heated by a fluid, but are suitable for heating the bellows of a tire hot press. Such heaters are more cost-intensive to produce and more maintenance-intensive in operation than the heater according to the invention. Known heaters for heating bellows must be designed for cyclic operation and must be able to be operated in a pressureless state, wherein these heaters must be designed for pressures of approximately 25 bar. In order to achieve this pressure, the heaters have a pressurizing component, such as a compressor. The bellows are subject to wear, so that parts of the bellows enter the fluid, and the heater must have a filter and must also be designed to be removable for regular maintenance work.

[0005] Consumers that are not heated with steam (i.e., for example, directly electrically heated) have proven to be disadvantageous in terms of heat distribution and are more complex and error-prone when it comes to control and regulation for setting the heat flow. A further disadvantage for such consumers is that significantly more complex adjustments are required when retrofitting existing consumers. The known methods must be redefined and commissioned, which may require new sampling by the customer. Summary of the invention

[0006] Against this background, the invention is based on the object of implementing a steam-heated consumer and method of the type described in the introduction which requires very little structural space, so that the costs for production and maintenance of the electrically driven heater are reduced, wherein the structural space required for laying the pipes should be small and the energy consumption during use should be reduced.

[0007] These objects are achieved by a device according to the features of claim 1 and by a method for operating an electrically driven heater according to the independent claim. The dependent claims relate to particularly advantageous developments of the invention.

[0008] These objects are achieved by a device according to the features of claim 1 and by a method for operating an electrically driven heater according to the independent claim. The dependent claims relate to particularly advantageous developments of the invention.

[0009] Therefore, according to the present invention, an electrically driven heater for a consumer heated by steam is proposed, the electrically driven heater comprising: a fluid storage container for receiving a fluid, a mold heated by the fluid, and a pipeline between the fluid storage container and the mold heated by the fluid, as well as a temperature sensor and / or a pressure sensor, and a heating device that is in thermal interaction with the fluid and can be operated by means of electrical energy, wherein the fluid storage container, the temperature sensor and / or the pressure sensor, and the heating device that can be operated by means of electrical energy are arranged in close proximity to the mold heated by the fluid.

[0010] Placing the electrically driven heater at the mold heated by the fluid can make the pipeline shorter and thus reduce the pipeline cost and maintenance cost as well as the structural space required for the pipeline. By making it possible to achieve a shorter pipeline, the heat dissipation occurring through the pipeline can be reduced and the efficiency of the electrically driven heater can be increased.

[0011] The mold heated by the fluid is a rigid mold, for example made of metal. Compared to a flexible mold (such as a bellows), a rigid mold has the advantage that it can be permanently overpressurized, so that an electrically driven heater can be realized that can be realized particularly cost-effectively and compactly. In addition, a rigid mold is subject to less wear when pressure is applied (especially in the case of pressure fluctuations) than a flexible mold.

[0012] “In thermal interaction” is understood to mean that heat transfer can be carried out in an optimal and efficient manner. For this purpose, the heating element that can be operated with electrical energy can be in direct contact with the fluid, but can also be thermally connected to the fluid, for example via a heat exchanger or a conductive connection.

[0013] "Placed close to a fluid-heated mold" is understood to mean that the fluid storage container, temperature sensor or pressure sensor and heating device capable of operating with the aid of electrical energy are placed on the fluid-heated mold, or are spaced at least no more than 10 meters, preferably no more than 5 meters, from the mold.

[0014] In particular for existing consumers heated by steam, it is also advantageous that no conditions for changes are provided, since on the other hand the method for existing products would have to be redefined and possibly put into use.

[0015] A preferred embodiment provides that the consumer heated by steam is a tire press, in particular a profiling section and / or an upper heating plate and / or a lower heating plate of the tire press. The electrically driven heater according to the invention is particularly advantageous for tire presses, since tire presses are regularly arranged in large numbers next to each other and thus require complex and elaborate piping.

[0016] A preferred embodiment provides that the pipeline has a flexible region for installation purposes, wherein other regions of the pipeline are rigid. The flexible region of the pipeline makes it possible to use the electrically driven heater in a simple manner, for example on conical ring containers of different sizes, thereby enabling production flexibility.

[0017] A preferred embodiment provides that the electrically driven heater is immovably mounted on the mold heated by the fluid. The immovable mounting makes it possible to dispense with flexible laying lines. In the known electrically driven heaters, flexible laying lines are necessary in order to enable the mold heated by the fluid to be movable.

[0018] A preferred embodiment provides that the heating device that can be operated by means of electrical energy is a heating coil and / or an induction generator that preferably inductively heats the wall of the fluid storage container and / or a heat engine, in particular a heat pump. The use of a heating coil makes it possible to realize a heating device that can be operated electrically particularly cost-effectively. However, it has been shown that the induction generator has a high durability and is also particularly maintenance-friendly, since it can be replaced without opening the fluid system. In addition, the high power transmission density thus made it possible to realize a particularly compact heating device. The heat engine has been shown to be particularly efficient in terms of energy consumption.

[0019] A preferred embodiment provides that the electrically driven heater has a valve circuit formed by a plurality of valves, and the actuation of the valve circuit enables the fluid to be conveyed through the mold heated by the fluid by means of steam pressure. With such a valve circuit, a conveying device for conveying the fluid can be omitted, thereby saving costs and structural space and improving the energy efficiency of the electrically driven heater.

[0020] A preferred embodiment provides that the electrically driven heater has a condensate container. The condensate container enables a valve circuit for conveying a fluid by means of vapor pressure to be realized in a simple manner.

[0021] A preferred embodiment provides that a fourth switchable valve is provided on the discharge line of the fluid-heated mold, a fifth switchable valve is provided on the liquid phase line leading from the condensate container to the fluid storage container, and a second switchable valve is provided on the gas phase line between the fluid storage container and the condensate container. This valve circuit makes it possible to achieve in a simple form that in a first switching position of the valve, a vapor flow can be achieved into the fluid-heated mold and a condensate flow can be achieved into the condensate container, while in a second switching position of the valve, a gravity-driven flow of condensate from the condensate container back into the fluid storage container can be achieved.

[0022] A preferred embodiment provides that the electrically driven heater is designed for an operating pressure of less than 12 bar, thereby enabling a particularly cost-effective and compact realization of the heater.

[0023] A preferred embodiment provides that the electrically driven heater has a pump for conveying the fluid. This makes it possible, for example, to accelerate the return of condensate to the fluid storage container and to select a more flexible arrangement of the fluid storage container relative to the arrangement of the condensate container. The valve circuit can also be designed in a simplified manner.

[0024] A preferred embodiment provides that the electrically driven heater is designed for continuous operation, wherein "continuous operation" is understood in particular to mean a substantially constant pressure, wherein process-related fluctuations may occur. However, an overpressure of more than one bar relative to the environment is at least permanently present. In addition, the temperature is preferably kept substantially constant.

[0025] A preferred embodiment provides that the electrically driven heater is a closed system, and therefore does not exchange volume flow with the environment, thereby making it possible to realize a particularly reliable and low-maintenance electrically driven heater.

[0026] A preferred embodiment provides that the fluid comprises water or consists of water, or is a heat transfer oil or a refrigerant. Water as a fluid has proven to be advantageous in terms of procurement and disposal and also has a high enthalpy of evaporation. It has proven to be advantageous that the heat transfer oil, due to its properties, does not significantly cause metal oxidation and can also operate at low pressures at high temperatures. The refrigerant as a fluid offers the advantage that, when using a heat engine, further fluids and further heat exchangers can be omitted.

[0027] A preferred embodiment provides that the electrically driven heater has an exhaust valve and / or a safety valve, so that simple exhaust of the electrically operated heater and simple and safe operation of the electrically operated heater can be achieved.

[0028] A preferred embodiment provides that the fluid storage container and the piping are sub-areas of the heat pipe. Implementing the fluid storage container and the piping as areas of the heat pipe allows a simple implementation of the electrically driven heater, since the vapor is conveyed back to the electrically driven heater driven by the vapor pressure and the condensate is conveyed back to the electrically driven heater driven by gravity and / or capillary forces. Valves and pumps can be omitted.

[0029] A preferred embodiment provides that the electrically driven heater is immovably mounted on the mold heated by the fluid. The immovable mounting makes it possible to dispense with flexible laying lines. In the known electrically driven heaters, flexible laying lines are necessary in order to enable the mold heated by the fluid to be movable.

[0030] According to the invention, a method for operating an electrically driven heater of a consumer heated by steam according to the invention is proposed, wherein measured values ​​of a temperature sensor and / or a pressure sensor are compared with theoretical values ​​and the thermal power of the electrically operable heating means is adjusted so that the measured values ​​approach the theoretical values. A simple and efficient method for operating a consumer heated by steam can be achieved.

[0031] A preferred embodiment provides that the condensate is conveyed into the steam generation container by means of a pump. A high and continuous conveying rate of the condensate can be achieved.

[0032] A preferred embodiment provides that by actuating the valve, the condensate is conveyed by vapor pressure in a first step into the condensate container and in a second step into the fluid storage container. The method can thus be operated without active fluid conveyance and is therefore particularly efficient.

[0033] According to the invention, the use of an electrically driven heater according to the invention for heating a consumer heated by steam, in particular for carrying out the method according to the invention, is proposed. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The present invention allows for a variety of embodiments. In order to further illustrate their basic principles, two of the embodiments are shown in the accompanying drawings and described below. In the accompanying drawings:

[0035] Figure 1 An electrically driven heater with a fluid storage container for use in a tire heating press with steam generation is shown;

[0036] Figure 2An electrically driven heater with a fluid storage container for use in a tire heating press with condensate recovery is shown; and

[0037] Figure 3 An electrically driven heater with a fluid storage container and a pump for a tire heating press is shown.

[0038] List of Reference Numerals

[0039] 1 Electric heater

[0040] 2 Tire hot press

[0041] 3 Fluid Storage Containers

[0042] 4. Laying pipelines

[0043] 5 Fluid-heated mold

[0044] 6 Flexible Area

[0045] 7 Grooves

[0046] 8 Condensate container

[0047] 9 3 / 2-way valve

[0048] 10 Safety valve

[0049] 11 Exhaust valve

[0050] 12 First switchable valve

[0051] 13 Second switchable valve

[0052] 14 Third switchable valve

[0053] 15 Fourth switchable valve

[0054] 16 Fifth switchable valve

[0055] 17 Temperature Sensor

[0056] 18 Pumps

[0057] 19 Heating devices capable of operating with electricity

[0058] g Gravity DETAILED DESCRIPTION

[0059] Figure 1An electrically driven heater 1 with a fluid storage container 3 for a tire heating press 2 is shown with steam generation. The electrically driven heater 1 is connected with a fluid storage container 3 with an electrically operable heating device 19 to a fluid-heated mold 5 in the form of a conical ring container of the tire heating press 2 via a rigid laying line 4. Only the flexible region 6 of the laying line 4 is provided for mounting the electrically driven heater 1 in steam chambers of different sizes in the conical ring container.

[0060] The conical ring container has a groove 7 to receive the water vapor generated by the electrically driven heater 1, which is supplied to the conical ring container by means of the laying pipe 4. In the groove 7, the water vapor dissipates heat to the conical ring container, condenses and collects in the lower area of ​​the groove 7. The other water vapor flow conveys the generated condensate through the laying pipe 4 against the gravity g to the condensate container 8, which is arranged above the fluid storage container 3 in terms of gravity g.

[0061] The condensate container 8 is connected via a 3 / 2-way valve 9 to a safety valve 10 , a vent valve 11 and a first switched valve 12 which is closed for maintenance purposes.

[0062] The condensate container 8 is connected via the second switchable valve 13 , which is switched to the blocking state, and together with the pipeline 4 to the fluid storage container 3 in order to conduct the vapor.

[0063] A third switchable valve 14 switched to conduction is arranged between the fluid storage container 3 and the conical ring container. The switchable valve 14 is used to calibrate, for example, a temperature sensor 17 in the closed state and in the state installed in the fluid storage container 3. In addition, the switchable valve 14 can also be closed during operation in order to briefly enable a slightly higher pressure in the steam generator. In addition, a fourth switchable valve 15 switched to conduction is arranged between the conical ring container and the condensate container 8, and a fifth switchable valve 16 switched to cutoff is arranged between the condensate container 8 and the fluid storage container 3 to recover water to the fluid storage container 3.

[0064] In the switching position of the switchable valves 13 , 14 , 15 , 16 , water vapor generated in the fluid storage container 3 , whose temperature is measured by the temperature sensor 17 , is conveyed into the recess 7 due to the vapor pressure and from there into the condensate container 8 as condensate.

[0065] If a sufficient amount of condensate has been conveyed into the condensate container 8, the fourth switchable valve 15 is closed and the second switchable valve 13 and the fifth switchable valve 16 are opened. No more condensate is supplied to the condensate container 8. The condensate is conveyed from the condensate container 8 into the fluid storage container 3 due to gravity g. Figure 2In the embodiment of the invention, a tire heating press 2 with a fluid storage container 3 is shown with a circuit for recovering condensate using switchable valves 13, 14, 15, 16. Figure 1 An electrically driven heater 1.

[0066] If the water has been transferred back to the fluid storage container 3, then execute Figure 1 The circuit of switchable valves 13 , 14 , 15 , 16 shown in FIG. 1 is shown in FIG. 1 and the method is started from the beginning.

[0067] Figure 3 An electrically driven heater 1 with a fluid storage container 3 and a pump 18 is shown for a tire heating press 2. The tire heating press 2 corresponds to Figure 1 The tire heat press. The electric drive heater 1 is Figure 1 An alternative embodiment, however, can be used with Figure 1 , for example by arranging the pump 18 between the recess 7 and the condensate container 8 .

[0068] The electrically driven heater 1 has a fluid storage container 3 with a temperature sensor 17 and is connected to a safety valve 10, a vent valve 11 and a first switchable valve 12 via a 3 / 2-way valve 9. The laying pipeline 4 is rigidly designed and has only a flexible area 6 for mounting on various conical ring containers. A pump 18 for conveying condensate is arranged between the conical ring container and the fluid storage container 3.

[0069] If the electrically driven heater 1 is operating, water vapor is transported from the fluid storage container 3 into the recess 7 due to its pressure. In the recess, the water vapor condenses into condensate, which is transported into the fluid storage container 3 by means of a pump 18.

Claims

1. An electrically driven heater (1) for a consumer (2) heated by steam, the electrically driven heater comprising: a fluid storage container (3) for receiving a fluid, a mold (5) heated by the fluid, and a pipeline (4) connecting the fluid storage container (3) and the mold (5) heated by the fluid, as well as a temperature sensor (17) and / or a pressure sensor, and a heating device (19) which is in thermal interaction with the fluid and can be operated by means of electrical energy, It is characterized in that The fluid storage container (3) and the temperature sensor (17) and / or the pressure sensor and the heating device (19) operable by means of electrical energy are arranged in the immediate vicinity of the fluid-heated mold (5).

2. The electrically driven heater (1) according to claim 1, characterized in that The consumer heated by steam is a tire press, in particular a shaping section and / or an upper heating plate and / or a lower heating plate of the tire press.

3. The electrically driven heater (1) according to claim 1 or 2, characterized in that: The laying pipe (4) has flexible areas for installation purposes, wherein other areas of the laying pipe (4) are rigid.

4. Electrically driven heater (1) according to one of the preceding claims, characterized in that The electrically driven heater (1) is simultaneously suitable and / or can be used to heat a consumer which is heated by exactly one fluid.

5. Electrically driven heater (1) according to one of the preceding claims, characterized in that The heating means operable by means of electrical energy are heating coils and / or induction generators which preferably inductively heat the wall of the fluid storage container (3) and / or heat engines, in particular heat pumps.

6. Electrically driven heater (1) according to one of the preceding claims, characterized in that The electrically driven heater (1) has a valve circuit, the operation of which enables the fluid to be conveyed through the fluid-heated mold (5) by means of steam pressure.

7. Electrically driven heater (1) according to one of the preceding claims, characterised in that The fluid-heated mold is made of metal.

8. Electrically driven heater (1) according to one of the preceding claims, characterised in that The valve circuit has a fourth switchable valve (15) on the discharge line of the fluid-heated mold (5), a fifth switchable valve (16) on the liquid phase line leading from the condensate container (8) to the fluid storage container (3), and a second switchable valve (13) on the gas phase line between the fluid storage container (3) and the condensate container (8).

9. Electrically driven heater (1) according to one of the preceding claims, characterised in that The electrically driven heater (1) is designed for a working pressure of less than 12 bar.

10. Electrically driven heater (1) according to one of the preceding claims, characterised in that The electrically driven heater (1) is designed for continuous operation.

11. Electrically driven heater (1) according to one of the preceding claims, characterised in that The electrically driven heater (1) is a closed system.

12. Electrically driven heater (1) according to one of the preceding claims, characterised in that The fluid comprises water or consists of water, or is a heat transfer oil or a refrigerant.

13. Electrically driven heater (1) according to one of the preceding claims, characterised in that The fluid storage container (3) and the laying pipeline (4) are sub-areas of a heat pipe.

14. A method for operating an electrically driven heater (1) of a steam-heated consumer (2) according to one of claims 1 to 12, characterized in that The measured value of the temperature sensor (17) and / or the pressure sensor is compared with a theoretical value, and the thermal power of the electrically operable heating device (19) is adjusted so that the measured value approaches the theoretical value.

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