EP1777478A1 - Regenerative heat exchanger and method for controlling clearance between the surface of the rotor and seal - Google Patents

Abstract

The regenerative heat exchanger includes a pneumatic measuring device (27) to check the sealing gap (13) between a seal (10) and the heat surface support (11). An interval (14) provided between the measuring device and heat surface support is bridged by a spacer body (17) and is at least so long that without any additional means for lowering the temperature the measuring device lies outside of a critical temperature range for the functioning of the measuring device. The measuring device has a fluid supply device and fluid pressure sensor (25). Independent claims are included for; (a) An adjusting device for seal of heat exchanger wherein the measuring device is pneumatic; (b) A pneumatic measuring device for checking sealing gap between seal and heat surface support; and (c) A method for determining sealing gap thickness between seal and heat surface support by providing a distance between measuring device and heat surface support, supplying fluid into spacer body through blower (26) and measuring the fluid pressure value through a pressure sensor and then comparing the measured values.

Description

The invention relates to a regenerative heat exchanger for heat exchange of gaseous media according to the preamble of claim 1, an adjusting device for use for a seal of a regenerative heat exchanger according to the preamble of claim 10 and a measuring device for checking a sealing gap between a seal and a Heizflächenenträger one Regenerative heat exchanger according to the preamble of claim 11. Furthermore, the invention relates to a method for determining a sealing gap thickness between a seal and a Heizflächenenträger a regenerative heat exchanger according to the preamble of claim 12 and another method for determining the change in a sealing gap thickness between a seal and a heating surface support of a regenerative heat exchanger according to the preamble of claim 14.

Known regenerative heat exchangers of this type are used both for air preheating (Luvos) and for gas preheating (Gavos). Here, a heat-emitting gaseous medium is passed through a Heizflächenenträger a regenerative heat exchanger. In the Heizflächenenträger heating surfaces or heat storage bodies are arranged, which are heated by the hot, heat-emitting gaseous medium. These heated heating surfaces in turn give off the heat to one or more heat-absorbing gaseous media, which also flow through the Heizflächenenträger from. The Heizflächenenträger can be stationary (as a stator) or rotating about its longitudinal axis (designed as a rotor).

If the heating surface support is designed as a rotor, the heating surfaces arranged in the rotor are rotated through the cold and warm gas flows, so that an exchange of heat between the gas flows is made possible. In the formation of the Heizflächenenträgers as a stator, the heat exchange is made possible by the fact that on both Statorstirnseiten rotating gas duct connections, so-called Rotary hoods are arranged so that the gas streams rotate through the stator. In both variants, therefore, the various areas of the Heizflächenenträgers alternately flows through all existing gas streams.

To separate the various gas streams from each other and to prevent leakage of gas from the Heizflächenenträger, in regenerative heat exchangers, one or more seals of various types are generally provided (eg., Radial seals, axial seals, circumferential seals, etc.). These gaskets are usually made of metal, especially cast iron. However, there are also embodiments that are made of other materials, such as ceramic.

Due to the high temperatures of the heat-emitting gaseous media, the Heizflächenenträger deformed during operation, especially in the area through which the heat-emitting gaseous medium flows. The deformation of the Heizflächenenträgers increase the sealing gaps between the seal and the Heizflächenenträger, thereby increasing the leakage rates drastically. To reduce the extent of this problem, it is known to make the seals adjustable, so that they can be tracked relative to the deforming Heizflächenenträger.

To automate the adjustment of the sealing systems of the regenerative heat exchanger, it is also known to form the regenerative heat exchanger with measuring devices which determine the degree of deformation of the Heizflächenenträgers or the distance between the seal and Heizflächenträger (sealing gap width) and forward this data to a control device, which actuates an actuator for setting the seal in dependence on the transmitted data.

From the DE 40 13 484 C2 For example, a regenerative heat exchanger is known in which for the automated adjustment of a sealing strip system on an end face of Heizflächenenträgers the sealing strip system opposite a non-contact sensor for measuring the distance between the sealing strip and the end face is present. Such a sensor may, for example, be a magnetic sensor which measures a change in the magnetic resistance, allowing conclusions to be drawn about the distance between the sealing strip and the heating surface carrier. Other known arrangements for determining the sealing gap thickness are, for example, sensing levers mounted on the heating surface support, which slide over the sealing surfaces.

All known measuring devices have in common that their sensors, probes or buttons are exposed to very high temperatures, since they are arranged in the vicinity of the seal or Heizflächenenträgers are. This often leads to damage to the measuring devices, whereby their life is relatively short. Furthermore, the measuring devices can be damaged by the pollutants partially present in the gaseous media. On the other hand, it is very expensive to design the measuring device so that they are more resistant to the temperatures. For magnetic sensors, this is achieved, for example, by the use of cooling systems. As a result, the production, installation and maintenance of the measuring devices is very expensive and expensive. For maintenance purposes, the measuring devices must also be accessible from the outside, whereby additional inspection openings must be formed in the regenerative heat exchanger, by the maintenance personnel can reach the sensors, buttons or sensors.

Therefore, the invention has for its object to provide devices and methods by which the sealing gap between the seal and Heizflächenenträger can be reliably checked, which are simple and inexpensive to manufacture or perform and where the measuring devices used have a long life.

The object is solved by the features of the independent claims. In dependent claims advantageous embodiments and developments of the invention are given.

The object is achieved with a regenerative heat exchanger for heat exchange of gaseous media with a seal for sealing a Heizflächenenträgers of the heat exchanger, and with a measuring device for checking a sealing gap between the seal and the Heizflächenenträger, wherein the measuring device is designed as a pneumatic measuring device. Further, between the measuring device and the Heizflächenenträger a bridged by a spacer body distance is provided which is at least so long that the measuring device without additional means for lowering the temperature is outside a critical for the functioning of the measuring device temperature range. The measuring device is thus operated in a region which causes no significant measurement errors with regard to the temperature near the Heizflächenenträger. Therefore, in the pneumatic measuring device, a conventional sensor can be used, which does not require special measures for protection against high temperatures.

For the purposes of the present invention, the expression "checking the sealing gap between seal and heating surface carrier" means that the distance between the seal and the heating surface carrier, the sealing gap thickness, is monitored by the measuring device at regular intervals during operation. For this purpose, on the one hand periodically determines the absolute value of the sealing gap width and when changing the value or in case of deviation of the value of a predetermined Value the seal to be adjusted accordingly. On the other hand, only the change in the thickness of the sealing gap can be determined without measurement or determination of the absolute sealing gap thickness value. As a result, the seal can be adjusted in accordance with the deformations of the Heizflächenenträgers, so that the sealing gap thickness is as constant as possible or is always in a predetermined sealing gap thickness range. The distance between the seal and the heating surface support is the distance between the inside of the seal and the opposite outside of the Heizflächenenträgers.

The advantage of the present invention is thus that the measuring device is arranged at a distance from the heating surface support and from the sealing strips and is therefore not exposed to the prevailing there, very hot temperatures or very hot gases. As a result, the life of the measuring device is significantly increased, and it eliminates costly and costly special measures to make the measuring device suitable for use in hot environments, such as cooling equipment, etc. The measuring device is located outside the gas streams, so that located in the gas streams Pollutants also can not adversely affect the measuring device. Furthermore, with the present invention, the sealing gap thickness or the change in the sealing gap thickness can be determined reliably with simple and cost-effective means. Furthermore, the metering device is easier to access for operators or maintenance personnel due to its spaced arrangement with the seal. Thus, in the design of the regenerative heat exchanger so that care must not be taken that special access options for the measuring device are available, whereby the structure of the regenerative heat exchanger is simplified as a whole.

In principle, the measuring device can be located anywhere as long as it is outside a critical temperature range for its functionality. Preferably, the measuring path is formed so that the measuring device is outside the heat exchanger. This ensures that the measuring device is exposed to relatively low temperatures. At the same time, the measuring device is particularly easy to access in this arrangement for maintenance or operating personnel.

The length of the measuring section or the distance between the measuring device and the heating surface carrier can basically be specified as desired. Preferably, the measuring device is arranged at a distance of 50 to 150 cm, particularly preferably at a distance of 80 to 100 cm, from the heating surface support. By field tests, the applicant has found that in common regenerative heat exchangers with the specified distances particularly good results are achieved.

Preferably, the measuring device has a fluid supply device and a fluid pressure sensor and / or volume flow sensor. Thus, a fluid such as air can be supplied into the sealing gap, which adjusts depending on the existing sealing gap thickness, a corresponding air pressure. With a large gap thickness, the air pressure is low, while with a small air gap thickness there is a high air pressure. In principle, a volumetric flow sensor can also be used. The principle is that with a large air gap thickness, a large volume flow can be transported through the air gap and vice versa. The air supply into the sealing gap is also advantageous in order to avoid dust deposits on a pressure sensor or volume flow sensor. This makes it possible to significantly reduce maintenance intervals in comparison to devices in the prior art.

Preferably, the distance between the measuring device and Heizflächenträger by means of a fluid-tight spacer body, in particular a tube or hose bridged, in principle, any rectilinear or curved spacer body can be used. In this connection, it is expedient that the one end of the spacer body is firmly attached to the seal and the other end of the spacer body is fixedly attached to the measuring device. This ensures that the measured values are not falsified by leakage and uncontrolled air leakage.

The measuring device can be designed in such a way that the absolute value of the sealing gap thickness is determined for checking the sealing gap by the measuring device making a comparison between the measured value and a value stored in a calibration table by at least one measured value. The comparison of the absolute measured values can be carried out by means of an evaluation unit which is provided in the measuring device or outside thereof.

The measuring device can also be designed such that the change in the sealing gap thickness is determined for checking the sealing gap. In this case, measured values are recorded and compared with one another at periodic intervals, with errors in the determination of absolute measured values, for example by an offset, having only a relatively small effect.

The object is further achieved according to the invention with a regenerative heat exchanger with an actuator for adjusting the seal and with a control device for controlling the actuator, wherein the measuring device is coupled to the control device for data transmission. The control device adjusts the seal by means of the actuator as a function of the data transmitted by the measuring device. Of importance is a predetermined sealing gap thickness range; if the measured values determined by the measuring device are outside the specified sealing gap thickness range, the seal is adjusted by means of the actuator.

The object is further achieved according to the invention by an adjusting device for use for a seal of a regenerative heat exchanger, which is provided for heat exchange of gaseous media, wherein the adjusting device an actuator for adjusting the seal, a control device for controlling the actuator and a measuring device for Checking a sealing gap between the seal and a Heizflächenenträger of the heat exchanger according to claim 10. The adjusting device can be used with measuring devices according to the invention which determine an absolute value and a relative value of the sealing gap thickness, the relative value representing the change in the sealing gap thickness.

In addition, the object is achieved according to the invention by the method according to claims 13 and 15.

Furthermore, the object is achieved according to the invention by a regenerative heat exchanger for heat exchange of gaseous media with a seal for sealing a Heizflächenenträgers of the heat exchanger, and with a measuring device for checking a sealing gap between the seal and the Heizflächenenträger, the measuring device for electronic distance measurement is and has a transmitter / receiver. Furthermore, a measuring path is provided between the transmitter / receiver and the Heizflächenenträger, which is at least so long that the measuring device is outside a critical for their functionality temperature range.

The invention thus consists in that the distance between the seal and the heating surface carrier is checked by means of electronic distance measurement. Electronic distance measurement is the determination of distances by means of the emission of signals. One possibility for electronic distance measurement is, for example, the measurement of the transit time of the signal. Measuring devices which measure the transit time comprise at least one transmitter, one receiver (possibly with amplifier) and one timer (interval counter). The transmitter and the receiver are often formed as one unit. Runtime is the time that a signal takes to travel the distance between the transmitter, a target, and back to the transmitter / receiver. With the measured transit time, along with the propagation speed of the signal, the distance traveled can be calculated, which is then halved to determine the distance between transmitter / receiver and target object. Another possibility with which a distance can be measured electronically is the interferometry or phase measurement. In this case, the phase angle between the emitted and returned signal is compared and a length or length change is determined therefrom. in principle For the present invention, all other known methods for electronic distance measurement by means of a signal, such as triangulation, can be used.

In principle, any type of wave signal can be used as signal, be it light, sound, matter or even waves propagating in a liquid, such as water waves. In practice, however, only electromagnetic waves or sound waves are normally used for electronic distance measurement.

The transceiver is preferably formed as a unit that can both transmit the signal and receive a return signal. In principle, however, a training with two separate units is possible. The transmitter / receiver is arranged at one end of a measuring path, while the Heizflächenenträger is provided at the other end. The signal emitted by the transmitter / receiver runs along the measuring path to the heating surface support, is reflected by it and runs along the measuring path back to the transmitter / receiver. In principle, any desired distance can be specified as the measuring path, although it must be ensured that the distance is so long that the transmitter / receiver and thus the measuring device are arranged in an area in which a temperature predominates which is essential for the functionality of the measuring device is not critical. The critical temperature depends on the measuring device used in each case, so that the measuring path is to be specified with reference to the respective application case. It is optimal if the measuring path is predetermined such that the ambient temperature of the transmitter / receiver corresponds to approximately room temperature. However, ambient temperatures in the range of 50 ° to 70 ° are often sufficient for the functionality of conventional measuring devices for electronic distance measurement. But it can also be used devices that work without damage at higher ambient temperatures. In principle, the measurement path can have any desired course, but the measurement path is preferably approximately rectilinear. If this is not possible, for example for structural reasons, it is readily possible to design the measuring section differently and to redirect the shaft signal by means of appropriate means, for example mirror surfaces, so that it follows the course of the measuring path.

Preferably, the wave signal emitted by the transmitter / receiver is an electromagnetic wave, in particular an electromagnetic wave, which lies in a frequency range of 10 ⁵ Hz to 10 ¹⁴ Hz. It is particularly preferable to use a laser beam, an infrared beam or a white light beam as the wave signal. Here, too, have carried out experiments by the applicant that these rays are particularly good for the electronic distance measurement in regenerative heat exchangers suitable. Furthermore, the transmitter / receiver units generating or receiving these beams are offered on the market as standard components and are therefore relatively inexpensive.

In order to protect the shaft signal from external influences that could falsify the measurement result, it is expedient that the measurement path runs within a tube. The term pipe is to be interpreted broadly in this context and also includes any channel-like arrangement and the like, through which the measuring section can be enclosed. Conveniently, the tube encases the measuring path at least in the range from the transmitter / receiver to the seal.

In a preferred embodiment of the invention, the measuring device is designed in such a way that it determines the changes in the distance between the seal and the heating surface carrier. For example, this can be achieved by measuring the distance between transmitter / receiver and heating surface carrier at regular intervals. By comparing the respectively determined results, the change in the sealing gap thickness over time can then be determined. The evaluation unit required for comparing the measured values can be integrated into the measuring device or designed as a separate structural unit which receives the measured data from the measuring device. Alternatively, the measuring device can be designed such that it determines the absolute value of the distance between the seal and the heating surface carrier. This can be achieved, for example, by measuring the distance between the heating surface carrier and the transmitter / receiver of the measuring device and comparing it with a constant distance between transmitter / receiver and seal (inside of the seal). Depending on the determined sealing gap thickness, the seal can then be adjusted accordingly.

In a further preferred embodiment, the measuring device is designed as an interferometer. Alternatively, the measuring device is designed for transit time determination. This has the advantage that the measuring device can be produced in a particularly simple and cost-effective manner, since the structural units (in particular transmitters, receivers and timepieces) required for determining the transit time are standard components and therefore relatively inexpensive.

If the measuring device is designed to determine the absolute value of the sealing gap thickness for checking the sealing gap, it is expedient to arrange the transmitter / receiver at a constant distance from the seal. This is to be carried out so that the distance during the entire operation, so even when adjusting the seal, remains constant. This can for example be achieved in that the transmitter / receiver is designed to be adjustable, and also adjusted during operation in dependence of the adjustment of the seal. Another possibility is the Transmitter / receiver by means of a carrier or holder firmly connected to the seal, so that the transmitter / receiver is adjusted with adjustment of the seal with and the distance thereby remains constant. It is important to ensure that there is always sufficient clearance between the seal and the transmitter / receiver. Conveniently, the distance from the transmitter / receiver to the inner side of the seal is used as a constant distance for the determination. Particularly preferred for this purpose, a tube is used, within which runs the measuring section and whose one end is fixedly attached to the seal and the other end fixed to the transmitter / receiver. The tube can be embedded in the seal or placed on this. Appropriately, in the region in which the tube rests against the seal, an opening in the seal is provided, so that the measuring path from the transmitter / receiver to the Heizflächenenträger is not blocked by the seal. Furthermore, in this embodiment, an evaluation unit is provided which compares the measured distance between transmitter / receiver and heating surface carrier with the constant distance between the transmitter / receiver and the seal and thereby determines the sealing gap thickness. This evaluation unit can be integrated in the measuring device or designed as a separate structural unit.

In a further preferred embodiment of the invention, the regenerative heat exchanger is provided with an actuator for adjusting the seal and with a control device for controlling the actuator. The measuring device is designed for data transmission to the control device. Furthermore, the control device is designed to adjust the seal by means of the actuator as a function of the data transmitted by the measuring device. The evaluation of the measured by the measuring device data is carried out by means of an evaluation unit, which may be formed in the measuring device, in the control device or as a separate unit. Furthermore, a sealing gap thickness range is predetermined and stored in the control device. If the determined sealing gap thickness is outside this sealing gap thickness range, the control device is designed to adjust the actuator in order to bring the sealing gap thickness back within the predetermined sealing gap thickness range. The sealing gap thickness range can be set arbitrarily, it is preferably in the range of 0.5 to 2 mm, particularly preferably 0.5 to 1 mm. The actuator may have an electric, pneumatic or hydraulic drive.

The object is further achieved by an adjusting device for use in a seal of a regenerative heat exchanger with an actuator, a control device and a measuring device according to claim 29. The adjusting device can be used both with measuring devices, by means of which the absolute value of the sealing gap thickness is determined, and with measuring devices, by means of which the change in the sealing gap thickness is determined. The measuring device transmits the data to the control device at predetermined, regular intervals.

Furthermore, the object is achieved by a measuring device for checking a sealing gap between a seal and a Heizflächenenträger a regenerative heat exchanger according to claim 30.

Furthermore, the object according to the invention is achieved by the method according to claim 31 and claim 33.

Fig. 1

eine geschnittene Teilansicht eines Regenerativ-Wärmetauschers mit einer Verstellvorrichtung inklusive einer ersten Messeinrichtung;

Fig. 2

ein Diagramm zur Erläuterung des Zusammenhangs zwischen Dichtspaltdicke, Fluiddruck und Volumenstrom;

Fig. 3

eine geschnittene Teilansicht eines Regenerativ-Wärmetauschers mit einer Verstellvorrichtung inklusive einer zweiten Messeinrichtung;

Fig. 4

ein Flussdiagramm, welches ein Verfahren zum Verstellen einer Dichtung eines Regenerativ-Wärmetauschers darstellt; und

Fig. 5

ein Flussdiagramm, welches ein weiteres Verfahren zum Verstellen einer Dichtung eines Regenerativ-Wärmetauschers darstellt.

The invention will be explained in more detail with reference to the drawing. They show schematically:

Fig. 1

a sectional partial view of a regenerative heat exchanger with an adjusting device including a first measuring device;

Fig. 2

a diagram for explaining the relationship between sealing gap thickness, fluid pressure and flow rate;

Fig. 3

a sectional partial view of a regenerative heat exchanger with an adjusting device including a second measuring device;

Fig. 4

a flow chart illustrating a method for adjusting a seal of a regenerative heat exchanger; and

Fig. 5

a flow chart illustrating another method for adjusting a seal of a regenerative heat exchanger.

Fig. 1 shows a sectional view of a part of a regenerative heat exchanger. The regenerative heat exchanger comprises a Heizflächenenträger 11, which is formed in the present example as a rotor. On an outer side of the Heizflächenenträgers 11 a to this outside substantially parallel seal 10 is arranged. Between seal 10 and heating surface support 11, a sealing gap 13 is provided. The sealing gap 13 is substantially constant over its entire length and height (not shown here). The seal 10 consists of two metal layers, which are firmly connected.

In the gasket 10, a local aperture 21 is formed which extends substantially orthogonal to the sealing plane and through the gasket. On the side facing away from the Heizflächenträger 11 side of the seal 10 is located in the region of the opening 21, a spacer body 17 such as a pipe with its front side flush to the seal 10 and is connected by welding firmly with the seal 10. The tube 17 is arranged so that it is flush with the opening 21. The tube 17 is straight and sits substantially perpendicular to the seal 10 on. In the further course of the pipe 17 passes through a further opening 22, which is formed in a wall of the regenerative heat exchanger housing 15 through. This wall is spaced from the seal 10 and disposed substantially parallel thereto. The opening 22 has a slightly larger diameter than the tube 17, so that there is an annular gap in the region of the opening 22 around the tube 17. As a result, the tube 17 is slidable along its longitudinal direction through the housing 15. On the side facing away from the seal 10 of the opening 22 is a seal 23 on the housing 15 at. The seal 23 also abuts the tube 17, so that the annular gap around the tube 17 in the region of the opening 22 is sealed to the outside. The seal 23 is held by a holder 24 which is mounted on the housing 15 (not shown here).

At the other end of the tube, which faces away from the seal 10, a measuring device 27 is arranged at a distance 14 from the Heizflächenenträger 11. The measuring device 27 has a pressure sensor 25 and a fluid supply device 26, which is for example a blower. The fluid supply device 26 serves to supply into the tube 17 a fluid such as air or another gas. This supplied air then penetrates along the tube 17 to the sealing gap 13, where it can escape depending on the size of the sealing gap 13 in a corresponding amount. If the sealing gap 13 is relatively small, only a small amount of air leaves the gap 13 or the tube 17. In this case, the tube 17 in a steady state has a constant air pressure which is detected by the air pressure sensor 25 at a sufficient distance 14 between the measuring device 27 and the heating surface carrier 11 can be. If the sealing gap 13 is relatively large, a larger volume flow emerges from the sealing gap 13, so that only a relatively low air pressure is established in the tube 17.

Such a pneumatic measuring device is advantageous because it always measures the actual gap 13, regardless of wear of a reference body such as the seal 10. Furthermore, deformations due to temperature variations, material cracks or run-out of mutually moving parts to changes the sealing gap 13th lead, which can thus be reliably detected. Further, when a fluid supply device 26 is used, dust deposits on the pressure sensor 25 can be kept low by the fluid supply with high reliability. Of course, it is equally possible to use a fluid suction device instead of the fluid supply device 26. Then air is not forced out of the sealing gap 13, but sucked into the sealing gap 13, wherein also a dependence between the sealing gap 13 and fluid pressure in the pipe 17 is.

The relationship between sealing gap thickness 13, fluid pressure and fluid volume flow is illustrated schematically in FIG. 2 by means of measured values, a fluid supply device 26 being used in the determination of the measured values. With a small sealing gap 13 with a sealing gap thickness s of, for example, s = 0.5 mm, there is a relatively high fluid pressure of about p = 87 mbar, so that only a relatively small volume flow of about V̇ = 0.5 m ³ / h by the Tube 17 and the sealing gap 13 is conveyed to the outside, see point A. In a large sealing gap 13 with a large sealing gap thickness of, for example, s = 3.8 mm, only a relatively low air pressure of about p = 5 mbar is achieved, wherein a volume flow of V̇ > 5 m ³ / h is transported out of the sealing gap 13, see point B. The numerical values are exemplary and depend on the dimensioning of the system components; With a heat exchanger of a different size, they can deviate many times from the values mentioned above.

If the pressure sensor 25 determines a measured value which, as described above, allows a direct inference to an existing sealing gap thickness, this measured value can be used to change the sealing gap thickness. The measured value is supplied to a control device 19 in which a comparison is made with values which are still within or already outside a predetermined sealing gap thickness range. If the measured value is classified as lying outside the sealing gap thickness range, a signal is sent to an actuator 20, which adjusts the position of the seal 10 by means of an actuating arm 201. If the sealing gap thickness continues to be measured during this adjustment movement, the sealing gap 13 can thus be adjusted to a value which lies within the sealing gap thickness range. This achieves regulation of the sealing gap thickness.

The measurement of the sealing gap from a safe distance can also be achieved with another measuring device. In Fig. 3, a structure is shown, which substantially coincides with the structure of FIG. In contrast, however, no pneumatic measuring device 27, but a measuring device 12 is provided for electronic distance measurement. The measuring device 12 has a transmitter / receiver 121, which can emit or receive an electromagnetic wave 16, which in the present example is an infrared ray. The infrared beam extends within the tube 17 substantially in the longitudinal direction of the tube until it finally passes through the opening 21 and hits the Heizflächenenträger 11. There, the infrared beam 16 is reflected. The reflected beam returns to the transmitter / receiver 121 in substantially the same way. The distance traveled by the infrared beam 16 between the transmitter / receiver 121 and the heating surface carrier 11 is the distance or the measuring path 14. The measuring path 14 is in the present example for clarity, shown outside of the tube 17, although of course within the Tube 17 runs. In the embodiment shown here, the measuring device 12 is thus spaced from the sealing gap 13 and even disposed outside of the housing 15, whereby the ambient temperature of the measuring device 12 at no time reaches a critical for the functioning of the measuring device 12 height.

The measuring device 12 further comprises a timer 123, which measures the time that the infrared beam 16 takes to get from the transmitter / receiver 121 to the Heizflächenenträger 11 and back. The measured time is transmitted by the timer 123 to an evaluation unit 122, which is likewise designed as part of the measuring device 12. The evaluation unit 122 uses the measurement data transmitted by the timer 123 to determine the length of the measurement path 14. In a next step, the evaluation unit 122 compares the determined length of the measurement path 14 with a predetermined constant distance 18 between the transmitter / receiver 121 of the measurement device 12 and the inside of the Seal 10. This distance 18 is also shown in Fig. 3 with a double arrow. The distance 18 is constant during the entire operation of the regenerative heat exchanger, since the tube 17 is both firmly connected to the seal 10 and fixed to the measuring device 12 and thus the measuring device 12 is adjusted by a change in position of the seal 10 by adjusting. By comparing the determined measuring section 14 with the constant distance 18, the thickness of the sealing gap 13 can be determined.

The value of the determined sealing gap thickness is transmitted from the measuring device 12 to the control device 19. This has stored a predetermined sealing gap thickness range and now checks whether the transmitted, actual value of the sealing gap thickness is within or outside the predetermined sealing gap thickness range. Once the actual value is outside the predetermined range, the control device, by means of a control pulse, the actuator 20, whereby this is set in motion and the seal 10 adjusted. The adjustment of the actuator 20 is shown by a double arrow in the drawing. The seal 10 can thus be adjusted in the direction of the Heizflächenenträgers 11 or away from it. The actuator 20 is fixedly mounted on the housing 15 and has a movable actuating arm 201 which is movable in the adjustment direction. The extent of the adjustment of the seal 10 is predetermined by the control device 19. This calculates the adjustment as a function of the deviation of the determined sealing gap thickness value from the predetermined sealing gap thickness range.

Fig. 4 shows a flow chart in which the steps of a method for adjusting the seal of a regenerative heat exchanger are shown. In a first step, an infrared signal is emitted by a measuring device. At the same time, a timer is started. The infrared signal runs along the measuring path and is reflected by the Heizflächenenträger the regenerative heat exchanger, so that it passes back to the measuring device and is received there. Once the reflected infrared signal is received, the timer is stopped. Based on the measured time, the distance covered by the infrared signal can now be determined by means of a transit time determination. It is important to ensure that the total distance traveled is halved, since only the easy way to determine. In a next step, the absolute value of the thickness of the sealing gap between the seal and heating surface carrier is calculated by subtracting a predetermined constant distance value for the distance from the inside of the seal to the measuring device from the determined distance. In the subsequent step, an evaluation unit checks whether the determined value of the sealing gap thickness is within a predetermined range. If this is the case, there is no adjustment of the seal and the sequence of the steps performed is restarted, that is, it is emitted a new infrared signal. If, on the other hand, the determined sealing gap thickness value is outside the predetermined range, the next step determines the exact deviation from the predetermined range. It is also determined whether the determined value is above or below the predetermined range, as this has an influence on the direction of adjustment of the seal. If the values are above the predetermined range, the seal is moved towards the heating surface carrier, ie it is tracked, whereas at a value lying below the predetermined range, the seal is led away from the heating surface carrier. After determining the deviation, the seal is adjusted by the amount of deviation. The adjustment can also be done by an amount that is slightly larger than the determined deviation. The adjustment may, for example, be made such that the seal is adjusted by the amount of deviation plus an amount corresponding to half the difference of the range end points of the predetermined range. This ensures that the value of the sealing gap thickness after the adjustment is substantially in the middle of the predetermined range. After the adjustment, the sequence of steps is restarted and thus an infrared signal is emitted again. Thus, the illustrated method is a sequence of steps that is continually repeated during operation of the regenerative heat exchanger. The start or the end of the sequence of steps takes place when the regenerative heat exchanger is switched on or off.

Fig. 5 shows a flow chart illustrating another method for adjusting a seal of a regenerative heat exchanger. In this method as well, an infrared signal is first emitted in the first step and the reflected infrared signal is received, the time duration being determined by means of a timer. In the subsequent step, the distance D _{i of} the emitted signal or of the reflected signal is determined analogously to the method illustrated in FIG. 4. In in a next step, the determined value of the distance D _{i is} stored. Thereafter, it is checked whether an older value D _i-1 exists in the memory. This value D _i-1 is the distance value that was determined based on the previous measurement. If no older measured value is present in the memory, the process is restarted and a new infrared signal is emitted. Otherwise, the values D _i and D _{i-1 are} compared in a next step. If there is no deviation between the two values and they are therefore identical, the sequence of steps is likewise reinitiated again. It can also be provided that the checking process is restarted if the deviation is not greater than a predetermined amount. If there is a deviation or the deviation is greater than the predetermined amount, in a next step, the seal is adjusted by the amount of deviation. Subsequently, in a next step, the stored values D _i in the memory are overwritten or deleted from the memory, and the process is restarted.

Claims (34)

Regenerative heat exchanger for heat exchange of gaseous media with a seal (10) for sealing a Heizflächenenträgers (11) of the heat exchanger, and with a measuring device (27) for checking a sealing gap (13) between the seal (10) and the Heizflächenenträger (11) .
characterized,
in that the measuring device (27) is designed as a pneumatic measuring device, wherein a distance (14) bridged by a spacer body (17) is provided between the measuring device (27) and the heating surface carrier (11), which distance is at least long enough for the measuring device ( 27) without additional means for lowering the temperature outside of a critical for the functioning of the measuring device (27) temperature range. Regenerative heat exchanger according to claim 1 with a heat exchanger housing (15),
characterized,
that the measuring device (27) outside the heat exchanger housing (15) is arranged. Regenerative heat exchanger according to claim 1 or 2,
characterized,
that the measuring device (27) at a distance of 50 cm to 150 cm, in particular a distance of 80 cm to 100 cm, from the heating surface (11) is arranged. Regenerative heat exchanger according to one of the preceding claims,
characterized,
that the measuring device has a fluid supply device (26) and a fluid pressure sensor (25) and / or volume flow sensor Regenerative heat exchanger according to one of the preceding claims,
characterized,
that the distance (14) by a fluid-tight spacer body (17), particularly a tube or hose, is bypassed. Regenerative heat exchanger according to claim 5,
characterized,
in that one end of the spacer body (17) is firmly attached to the seal (10) and the other end of the spacer body (17) is fixedly attached to the measuring device (27). Regenerative heat exchanger according to one of the preceding claims,
characterized,
in that the measuring device (27) is designed to determine the change in the sealing gap thickness for checking the sealing gap (13). Regenerative heat exchanger according to one of claims 1 to 6,
characterized,
in that the measuring device (27) is designed to determine the absolute value of the sealing gap thickness for checking the sealing gap (13) by the measuring device (27) making a comparison between the measured value and a value stored in a calibration table by at least one measured value , Regenerative heat exchanger according to claim 8, comprising an actuator (20) for adjusting the seal (10) and with a control device (19) for controlling the actuator (20), wherein the measuring device (27) for data transmission to the control device (19) coupled and the control device (19) adjusts the seal (10) by means of the actuator (20) as a function of the data transmitted by the measuring device (27),
characterized,
that a sealing gap thickness range is predetermined and the control means (19) is formed, the gasket (10) by means of the actuator (20) to adjust, when measured by the measuring means (27) is located sealing gap thickness of the sensor is outside the predetermined seal gap thickness range. Adjustment device for use with a seal (10) of a regenerative heat exchanger, which is provided for heat exchange of gaseous media, with an actuator (20) for adjusting the seal (10), with a control device (19) for controlling the actuator (20) , and with a measuring device (27) for checking a sealing gap (13) between the seal (10) and a heating surface support (11) of the heat exchanger, wherein the measuring device (27) is designed for data transmission to the control device (19) and the control device (27). 19) adjusts the seal (10) by means of the actuator (20) as a function of the data transmitted by the measuring device (12),
characterized,
in that the measuring device (27) is designed as a pneumatic measuring device, wherein a distance (14) bridged by a spacer body (17) is provided between the measuring device (27) and the heating surface carrier (11), which distance is at least long enough for the measuring device ( 27) without additional means for lowering the temperature outside of a critical for the functioning of the measuring device (27) temperature range. Measuring device for checking a sealing gap (13) between a seal (10) and a heating surface support (11) of a regenerative heat exchanger, which is provided for heat exchange of gaseous media,
characterized,
in that the measuring device (27) is designed as a pneumatic measuring device, wherein a distance (14) bridged by a spacer body (17) is provided between the measuring device (27) and the heating surface carrier (11), which distance is at least long enough for the measuring device ( 27) without additional means for lowering the temperature outside of a critical for the functioning of the measuring device (27) temperature range. Method for determining a sealing gap thickness between a seal (10) and a heating surface support (11) of a regenerative heat exchanger, which is provided for heat exchange of gaseous media,
characterized by the following steps: Providing a distance (14) between a measuring device (27) and the Heizflächenenträger (11) by a spacer body (17); Supplying a fluid volume flow into the spacer body, in particular by means of a blower (26); Measuring a fluid pressure measured value associated with the fluid volume flow by means of a pressure sensor (25) or a volumetric flow measured value by means of a volume flow sensor; Calculating the sealing gap thickness by comparing the measured value with a value stored in a calibration table. Method for adjusting a seal (10) of a regenerative heat exchanger, which is provided for heat exchange of gaseous media, by means of an adjusting device, comprising: - an actuator (20); - a control device (19); and a measuring device (27), characterized by the following steps: Determining a sealing gap thickness according to claim 12; Check whether the determined value is outside a specified sealing gap thickness range; possibly Transmitting a signal (16) from the measuring device (27) to the control device (19); and Driving the actuator (20) and adjusting the seal (10). Method for determining the change in a sealing gap thickness between a seal (10) and a heating surface support (11) of a regenerative heat exchanger, which is provided for heat exchange of gaseous media,
characterized by the following steps: Providing a distance (14) between a measuring device (27) and the Heizflächenenträger (11) by a spacer body (17); Supplying a fluid volume flow into the spacer body, in particular by means of a blower (26); Measuring a fluid pressure measured value associated with the fluid volume flow by means of a pressure sensor (25) or a volumetric flow measured value by means of a volume flow sensor; Repeating the measurement at predetermined intervals; and Calculating the sealing gap thickness change by comparing the measured values with the measured value of the respective preceding measurement. Method for adjusting a seal (10) of a regenerative heat exchanger, which is provided for heat exchange of gaseous media, by means of an adjusting device, comprising: - an actuator (20); - a control device (19); and a measuring device (27), characterized by the following steps: Determining the seal gap thickness change according to claim 14; Transmitting the value of the change to the control device (19); and Driving the actuator (20) and adjusting the seal (10) by the value of the change. Regenerative heat exchanger for heat exchange of gaseous media with a seal (10) for sealing a Heizflächenenträgers (11) of the heat exchanger, and with a measuring device (12) for checking a sealing gap (13) between the seal (10) and the Heizflächenenträger (11) .
characterized,
in that the measuring device (12) is designed for electronic distance measurement and has a transmitter / receiver (121), wherein a measuring path (14) which is at least as long is provided between the transmitter / receiver (121) and the heating surface carrier (11). the measuring device (12) is outside a critical temperature range for its functionality. Regenerative heat exchanger according to claim 16 having a heat exchanger housing (15),
characterized,
that the measuring device (12) outside the heat exchanger housing (15) is arranged. Regenerative heat exchanger according to claim 16 or 17,
characterized,
that the measuring device (12) at a distance of 50 cm to 150 cm, in particular a distance of 80 cm to 100 cm, from the heating surface (11) is arranged. Regenerative heat exchanger according to one of claims 16 to 18,
characterized,
in that the transmitter / receiver (121) emits a wave signal, in particular an electromagnetic wave (16). Regenerative heat exchanger according to claim 19,
characterized,
that the wave signal (16) is a laser beam, an infrared beam or a beam of white light. Regenerative heat exchanger according to one of claims 16 to 20,
characterized,
that the measuring section (14) extends within a tube (17) Regenerative heat exchanger according to one of claims 16 to 21,
characterized,
in that the measuring device (12) is designed to determine the change in the sealing gap thickness for checking the sealing gap (13). Regenerative heat exchanger according to one of claims 16 to 21,
characterized,
in that the measuring device (12) is designed to determine the absolute value of the sealing gap thickness for checking the sealing gap (13). Regenerative heat exchanger according to one of claims 16 to 23,
characterized,
that the measuring device (12) is formed as interferon meters. Regenerative heat exchanger according to one of claims 16 to 23,
characterized,
in that the measuring device (12) is designed to check the sealing gaps (13) by means of a transit time determination of a wave signal (16). Regenerative heat exchanger according to claim 25,
characterized,
that the measuring device (12) is designed to determine the absolute value of the sealing gap thickness for checking the sealing gap (13);
that the transmitter / receiver (121) is arranged at a constant distance (18) from the seal (10); and
in that the measuring device (12) is designed to determine the sealing gap thickness by comparing the constant distance (18) between transmitter / receiver (121) and seal (10) with a measured distance between transmitter / receiver (121) and heating surface carrier (11). Regenerative heat exchanger according to claim 26,
characterized,
that the measuring section (14) extends within a tube (17); and
in that one end of the tube (17) is firmly attached to the seal (10) and the other end of the tube (17) is fixedly attached to the transmitter / receiver (121). Regenerative heat exchanger according to one of claims 23 to 27, comprising an actuator (20) for adjusting the seal (10) and with a control device (19) for controlling the actuator (20), wherein the measuring device (12) for data transmission to the control device (19) is coupled and the control device (19) adjusts the seal (10) by means of the actuator (20) as a function of the data transmitted by the measuring device (12),
characterized,
that a sealing gap thickness range is predetermined and the control means (19) is formed, the gasket (10) by means of the actuator (20) to adjust, when measured by the measuring means (12) the sealing gap thickness of the sensor is outside the predetermined seal gap thickness range. Adjustment device for use with a seal (10) of a regenerative heat exchanger, which is provided for heat exchange of gaseous media, with an actuator (20) for adjusting the seal (10), with a control device (19) for controlling the actuator (20) , and with a measuring device (12) for checking a sealing gap (13) between the seal (10) and a heating surface support (11) of the heat exchanger, wherein the measuring device (12) is designed for data transmission to the control device (19) and the control device (12). 19) adjusts the seal (10) by means of the actuator (20) as a function of the data transmitted by the measuring device (12),
characterized,
in that the measuring device (12) is designed for electronic distance measurement and has a transmitter / receiver (121), wherein a measuring path (14) which is at least as long is provided between the transmitter / receiver (121) and the heating surface carrier (11). the measuring device (12) is outside a critical temperature range for its functionality. Measuring device for checking a sealing gap (13) between a seal (10) and a heating surface support (11) of a regenerative heat exchanger, which is provided for heat exchange of gaseous media,
characterized,
in that the measuring device (12) is designed for electronic distance measurement and has a transmitter / receiver (121), wherein a measuring path (14) which is at least as long is provided between the transmitter / receiver (121) and the heating surface carrier (11). the measuring device (12) is outside a critical temperature range for its functionality. Method for determining a sealing gap thickness between a seal (10) and a heating surface support (11) of a regenerative heat exchanger, which is provided for heat exchange of gaseous media,
characterized by the following steps: Providing a measuring section (14) between a transmitter / receiver (121) and the heating surface support (11); Generating and emitting an electromagnetic wave (16) by means of the transmitter / receiver (121); Keeping a predetermined distance constant between the transmitter / receiver (121) and the seal (10); Measuring the length of the measuring section (14) by means of a transit time determination of the shaft (16); and Calculating the seal gap thickness by comparing the measured value with the predetermined constant distance (18) between the transmitter / receiver (121) and the seal (10). Method for adjusting a seal (10) of a regenerative heat exchanger, which is provided for heat exchange of gaseous media, by means of an adjusting device, comprising: - an actuator (20); - a control device (19); and a measuring device (12), characterized by the following steps: Determining a sealing gap thickness according to claim 31; Check whether the determined value is outside a specified sealing gap thickness range; possibly Transmitting a signal (16) from the measuring device (12) to the control device (19); and Driving the actuator (20) and adjusting the seal (10). Method for determining the change in a sealing gap thickness between a seal (10) and a heating surface support (11) of a regenerative heat exchanger, which is provided for heat exchange of gaseous media,
characterized by the following steps: Providing a measuring section (14) between a stationary transmitter / receiver (121) and the heating surface support (11); Generating and emitting an electromagnetic wave (16) by means of the transmitter / receiver (121); Measuring the length of the measuring section (14) by means of a transit time determination of the shaft (16); Repeating the measurement at predetermined intervals; and Calculating the sealing gap thickness change by comparing the measured values with the measured value of the respective preceding measurement. Method for adjusting a seal (10) of a regenerative heat exchanger, which is provided for heat exchange of gaseous media, by means of an adjusting device, comprising: - an actuator (20); - a control device (19); and a measuring device (12), characterized by the following steps: Determining the sealing gap thickness change according to claim 33; Transmitting the value of the change to the control device (19); and Driving the actuator (20) and adjusting the seal (10) by the value of the change.

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