Abstract:
A condensate evaporator with an electrically heatable accommodation chamber for water of condensation which is produced in a cooling device and is to be evaporated. A design which is as compact and simple is achieved because the accommodation chamber is formed by a tube section on whose outer face at least one heating element which is in thermal contact with the tube section is arranged and at one end of which an inlet for the supplied water of condensation is arranged and at an other end of which an outlet for the steam which is produced from the water of condensation by the heating element is arranged. This invention also relates to a cooling device, in particular for a switchgear cabinet, having a condensate evaporator according to this invention.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    This invention relates to a cooling device, particularly a switchgear cabinet, having a cooling circuit which has an evaporator, a condenser and a compressor, in which condensation water generated is evaporated in a condensate-vaporizing device having an electrically heatable condensation water receiving chamber. 
         [0003]    2. Discussion of Related Art 
         [0004]    Known cooling devices are for example employed for air-conditioning switchgear cabinets, in which a number of electronic components are housed, which emit a considerable amount of dissipated energy in the form of heat. The condensation water created at the evaporator drips off and is caught in a condensate collecting vessel arranged underneath. It is known to feed the condensation water by a pump arrangement from the condensate collecting vessel to an electrically heated condensate-vaporizing device, in which the condensate evaporates and is dissipated to the environment in the form of water vapor. 
         [0005]    Reaching a filling limit of the condensation water in the condensate collecting vessel is determined by a sensor arrangement, or a float-type switch, which switches the pump arrangement on and the heater in the condensate collecting vessel. As soon as the condensate level in the condensate collecting vessel drops below a predetermined fill level, the pump arrangement, as well as the heater in the condensate-vaporizing device, is shut off. This solution is very elaborate in a technical sense and thus cost expensive and also error-prone due to the complex construction. Also, such an arrangement takes up a relatively large structural volume. 
         [0006]    A cooling device is known from German Patent Reference DE 198 17 247 A1, in connection with which a heating device is arranged in the condensate collecting vessel for vaporizing the condensation water, so that some type of a condensate-vaporizing device is created. Because of the limited structural space such condensate-vaporizing devices may only have small structural size, and the vaporizing output is small. When a large amount of condensate is accumulating, condensate runs off past a provided safety overflow and is discharged through a run-off hose into the environment. Undesired puddles can form on the ground here. 
       SUMMARY OF THE INVENTION 
       [0007]    It is one object of this invention to provide a condensate removal by condensate evaporation, in particular in connection with a cooling device, by which resulting condensate can be removed with the least possible technical outlay by evaporation without the danger of puddle formation. Also, the condensate-vaporizing device should be constructed as compactly and simply as possible. 
         [0008]    This object of this invention is attained with a condensate-vaporizing device having characteristics described in this specification and in the claims, and by a cooling device. 
         [0009]    In connection with the condensate-vaporizing device in accordance with this invention, the receiving chamber for the condensation water to be evaporated is formed by a pipe section, on whose exterior at least one heating element is arranged, which is in thermal contact with the pipe section. An inlet for the fed-in condensation water is arranged at one end of the pipe section, and at the other end of the pipe section an outlet for the water vapor generated by the heating element from the condensation water. 
         [0010]    The structure of the condensate-vaporizing device is simple. Only a few components are used, so that the manufacturing costs are low and there is functional dependability. With this condensate-evaporating device it is possible to completely evaporate condensation water introduced in to the receiving chamber, particularly if the heating element is continuously operated during operation of the cooling device. With these measures, it is possible to achieve condensation water entering the receiving chamber which is immediately heated and evaporated. No additional sensing arrangements for determining the level of fluids are required. 
         [0011]    For preventing either condensation water or water vapor from being conducted back, or flashes back, through the condensation water inlet because water vapor is formed in the pipe section, it is possible to form an inlet labyrinth at the condensation water inlet, which has a downwardly open inlet opening below the condensation water level and a return flow blocking device for the condensation water to be evaporated, which is in the pipe section. 
         [0012]    It is possible to omit the use of a pumping arrangement, because in a preferred embodiment, the downwardly open inlet opening is arranged in direct flow contact with a condensate collecting vessel and below the condensation water level of the condensation water present in the condensate collecting vessel. It is thus achieved that the condensation water flows into the pipe section because of gravity, wherein the amount of condensation water flowing into the pipe section is determined by the condensation water level in the condensate collecting vessel and by the return flow blocking device. 
         [0013]    In accordance with one embodiment, the return flow blocking device can be formed by a wall section which projects vertically upward. Here, the wall section is inserted into the inlet labyrinth so that the inflowing condensation water can only flow over its upward pointing edge. 
         [0014]    A water vapor outlet pipe section can be formed at the water vapor outlet at the end of the pipe section, which has an upwardly open outlet opening, to which an outlet pipe or outlet hose can be connected. This represents a particularly simple form of water vapor removal from the cooling device. 
         [0015]    In accordance with one embodiment, the condensate-vaporizing device can have an evaporator unit, formed by an arrangement including at least the pipe section, the heating element and a heat-resistant and heat-conducting molded element. This molded element maintains the pipe section in a corresponding recess and also has a receptacle for the heating element. 
         [0016]    To produce the evaporator unit in a particularly cost-effective manner, while still assuring the required heat resistance, or conducting capability, the molded element can be made of aluminum and can, in particular, be produced by an aluminum extrusion process. 
         [0017]    To assure a particularly good heat transfer from the heating element to the condensation water in the pipe section, the pipe section can be designed as a metal pipe section. Particularly effective corrosion resistance is achieved if the pipe section is made of high-grade steel. 
         [0018]    In a particularly simple and cost-effective embodiment, the pipe section can have a circular cross section. This also permits a particularly good heat transfer from the heating element to the condensation water to be evaporated. 
         [0019]    In order to securely attach the condensate evaporator inside a cooling device, and also to be able to later retrofit an existing cooling device with a condensate evaporator in a simple manner, wherein the uncontrolled exit of condensation water and water vapor from the condensate evaporator is to be assuredly prevented, the evaporator unit can be arranged inside a closed, watertight housing. 
         [0020]    In one embodiment, the housing can have a housing element which extends around the evaporator unit and parallel in relation to the pipe section. A cover can be respectively applied to the two open ends of the substantially hollow-cylindrical housing element. Thus, an inlet cover is arranged at the inlet end of the pipe section, and an outlet cover at the outlet side of the pipe section. 
         [0021]    For achieving a fluid-proof connection between the pipe section end on the inlet side and the inlet cover, the end of the pipe section at the inlet side can extend into a corresponding through-opening formed in the inlet cover, wherein the inlet labyrinth is embodied on the exterior of the inlet cover facing away from the pipe section. 
         [0022]    The technical production cost outlay can be minimized and the number of housing elements reduced if the inlet cover is a one-piece plastic injection-molded element with the housing element surrounding the evaporator unit, and if an approximately cup-shaped housing element for receiving the evaporator unit is formed. Also, the inlet cover can be embodied as a one-piece plastic injection-molded element together with the inlet labyrinth. 
         [0023]    For achieving a fluid-proof connection between the pipe section end on the outlet side and the outlet cover, the end of the pipe section at the outlet side can extend into a corresponding through-opening formed in the outlet cover, wherein the water vapor outlet pipe section is on the exterior of the outlet cover facing away from the pipe section. The outlet cover can be embodied as a one-piece plastic injection-molded element together with the water vapor outlet pipe section. 
         [0024]    A receptacle for the heating element is in the evaporation unit, which is open at least in the direction toward the inlet cover and/or in the direction toward the outlet cover for inserting the heating element when the housing or the housing covers is not yet attached. With the housing covers attached, the inlet cover or the outlet cover close off the respective receiving opening in the assembled state and secure the heating element. 
         [0025]    For supplying the heating element with electric current, supply openings for supplying the heating element with electrical current can be formed in the inlet cover and/or the outlet cover. 
         [0026]    In accordance with one embodiment which is easy to realize with production technology, the housing covers can be connected with the housing element surrounding the evaporator unit by ultrasonic welding. 
         [0027]    The condensate evaporator in accordance with this invention can be used in connection with a cooling device, in particular for a switchgear cabinet, having a cooling circuit which has an evaporator, a condenser and a compressor. In accordance with one preferred embodiment, a condensate collecting vessel for collecting the condensation water being generated can be provided. In this embodiment, the condensate collecting vessel is in direct flow contact with the condensate-vaporizing device, so that the condensation water flows into the condensate-vaporizing device because of the effect of gravity. An additional conveying device, such as a pump, for example, can be omitted. 
         [0028]    In order to not require long connecting lines between the condensate collecting vessel and the condensate evaporator, the condensate-vaporizing device can be arranged directly on the condensate collecting vessel. A more compact arrangement can be realized if the condensate-vaporizing device is arranged in or on the condensate collecting vessel, in which case the inlet opening of the inlet labyrinth is arranged in the condensation water and below the condensation water level. 
         [0029]    To continuously evaporate the condensation water which is respectively generated during operation of the cooling device, and thus to reduce the creation of condensation water collections, which must be removed, the condensate-vaporizing device can be continuously heated at least during the operation of the cooling vessel. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]    This invention is explained in greater detail in view of a preferred embodiment of a condensate-vaporizing device introduced into a cooling device, shown in the drawings, wherein: 
           [0031]      FIG. 1  shows a schematic sectional lateral view of a condensate-vaporizing device arranged directly on a condensate collecting vessel of a cooling device; 
           [0032]      FIG. 2  shows the condensate-vaporizing device in accordance with  FIG. 1 , in a perspective exploded view; and 
           [0033]      FIG. 3  shows the condensate-vaporizing device in accordance with  FIGS. 1 and 2  in a transparent representation and on the outlet cover from above. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0034]    In a schematic lateral view and in section,  FIG. 1  shows a condensate-vaporizing device in accordance with this invention, which is arranged directly on a condensate collecting vessel  22  of a cooling device, not shown in detail, for a switchgear cabinet. The cooling device has a cooling circuit with an evaporator, a condenser and a compressor. The condensation water  12  generated in the cooling device is collected in the condensate collecting vessel  22 . 
         [0035]    In a non-represented embodiment, the condensate collecting vessel can also be connected with the condensate-vaporizing device via a pipeline or hose. In accordance with a further non-represented embodiment, the condensation water created can also be fed directly to the condensate-vaporizing device, such as where no condensate collecting vessel within the meaning of  FIG. 2  is provided. 
         [0036]    The condensation water  12  flows into the condensate-vaporizing device via an inlet opening  32 , which is in direct contact with the condensation water  12  collected in the condensate collecting vessel  22  and is arranged below the condensation water level  28 . 
         [0037]    The condensate-vaporizing device has a receiving chamber  10 , which can be electrically heated, for the condensation water  12  to be evaporated. The receiving chamber  10  is formed by a pipe section  14 , made of high-grade steel, which extends horizontally through  FIG. 1 , on whose exterior a PTC heating element  16  is arranged above the pipe section  14 , extends parallel with and is in thermal contact with the pipe section  14 . An inlet  20  for the condensation water  12  supplied from the condensate collecting vessel  22  is at an end  18  of the pipe section  14 , and an outlet  26  for the water vapor generated from the condensation water at the other end  24 . 
         [0038]    The PTC heating element  16  is continuously provided with a voltage during the operation of the cooling device, or as long as condensation water is created in it. During this the PTC heating element generates a constant surface temperature of approximately 220° C. This temperature is sufficient for heating the condensation water in the pipe section  14 , and to evaporate it. 
         [0039]    An inlet labyrinth  30  is formed in the condensation water inlet  20 , which has a downwardly open inlet opening  32  and a return flow blocking device for the condensation water  12  to be evaporated and present in the pipe section  14 . Because of the effect of gravity, the condensation water flows into the pipe section  14 , wherein the amount of condensation water  12  flowing into the pipe section is determined by the condensation water level  28  in the condensate collecting vessel  22  and by the return flow blocking device. The return flow blocking device is formed by a wall section  70 , which projects vertically upward, wherein the wall section  70  is inserted into the inlet labyrinth  30  so that the inflowing condensation water can only flow over it at its upward pointing edge. In its lower area, the wall section  70  is sealingly connected with the inlet labyrinth  30 . 
         [0040]    The water vapor generated in the heated pipe section  14  exits from the water vapor outlet  26  located opposite the condensate inlet  20  and shown in  FIG. 1  on the right side of the pipe section  14 . A water vapor outlet pipe section  34  is formed on the water vapor outlet  26  and has an upwardly open outlet opening  36 , to which an outlet pipe or an outlet hose can be connected. 
         [0041]      FIG. 2  shows the condensate-vaporizing device in accordance with  FIG. 1  in a perspective exploded view. The condensate-vaporizing device is surrounded by a closed, watertight housing  44 , shown in  FIG. 2  in the opened state during mounting, so that the interior construction of the condensate-vaporizing device in particular also becomes clear. 
         [0042]    The pipe section  14  has a circular cross section and is maintained inside a heat-resistant and heat-conducting molded element  40 . This molded element  40  is made from aluminum by extrusion. 
         [0043]    A substantially cylinder-shaped recess  38  is in the molded element  40  and corresponds with the circular exterior cross section of the pipe section  14 . The pipe section  14  is pressed into the recess  38 . 
         [0044]    The molded element  40  has an approximately rectangular receptacle  42  for the PTC heating element  16 , which is arranged above the pipe section  14  and extends parallel with respect to it. The arrangement of the pipe section  14 , the heating element  16  and the molded element  40  forms a unit which can be called an evaporation unit  14 ,  16 ,  40 . 
         [0045]    The housing  44  has a housing element  46 , which surrounds the evaporation unit  14 ,  16 ,  40  and extends parallel with respect to the pipe section  14 . In inlet cover  48 , which is produced as a one-piece plastic injection-molded element together with the housing element  46  surrounding the evaporation unit  14 ,  16 ,  40 , is arranged on the housing element  46  at the end  18  on the inlet side of the pipe section  14 . As  FIG. 2  shows, an approximately cup-shaped housing element  46 ,  48  for receiving the evaporation unit  14 ,  16 ,  40  is thus created. 
         [0046]    An outlet cover  50  can be mounted at the outlet end  24  of the pipe section  14 . In the unassembled state, the receptacle  42  for the PTC heating element is open in the direction toward the outlet cover  50  so that the PTC heating element can be inserted. Then, in the assembled state, the outlet cover  50  closes the receptacle opening  56  and maintains the heating element  16  in position. 
         [0047]    In the assembled state, the inlet cover  48  and the outlet cover  50 , together with the housing element  46 , form the closed housing  44 . 
         [0048]    In view of  FIG. 1 , it is clear that the end  18  at the inlet side of the pipe section  14  extends into a corresponding through-opening  52  formed in the inlet cover  48  and ends with it in a fluid-tight manner. The inlet labyrinth  39  is attached to the exterior of the inlet cover  46  facing away from the pipe section  14 . The inlet cover  48  is embodied as a one-piece plastic injection-molded element together with the inlet labyrinth  30 . 
         [0049]    The end  24  at the outlet side of the pipe section  14  extends into a corresponding through-opening  54  formed in the outlet cover  50  and ends with it in a fluid-tight manner. The water vapor outlet pipe section  34  is attached to the exterior of the outlet cover  50  facing away from the pipe section  14 . The outlet cover  50  is formed as a one-piece plastic injection-molded element together with the water vapor outlet pipe section  34 . 
         [0050]    As  FIG. 2  shows, supply openings  58   a  and  58   b  for electrical current supply lines for the heating element  16  are formed in the outlet cover  50 . 
         [0051]    The inlet cover  48  and the outlet cover  50  are connected by ultrasonic welding with the housing element  46  surrounding the evaporation unit  14 ,  16 ,  40 . 
         [0052]    For mounting the condensate-vaporizing device on a mounting plate or mounting holder of a switchgear cabinet or cooling device, respectively two threaded bores  72   a  and  72   b , or  74   a  and  74   b , which are open toward the bottom and extend vertically with respect to the pipe section  14 , are provided in the inlet cover  48  and in the outlet cover  50 . Threaded screws can be screwed into the threaded bores. 
         [0053]    In accordance with another embodiment, tabs are formed on or attached to the inlet cover  48  and to the outlet cover  50 , which are used for fastening the condensate-vaporizing device to a mounting plate or mounting holder of a switchgear cabinet or a cooling device. It is thus possible to provide threaded bores in the tabs. 
         [0054]    In a transparency representation and view from above on the outlet cover  50 ,  FIG. 3  represents the condensate-vaporizing device shown in  FIGS. 1 and 2 . The installed position of the molded element  40  inside the housing  44 , or of the housing element  45  surrounding the molded element  40 , can be clearly seen by  FIG. 3  in particular. For assuming a positionally secure seating of the molded element  40  inside the housing element  46 , the housing element  40  rests with its left and right lateral areas  76   a  and  76   b  on a left and right support  78   a  and  78   b  formed on the interior wall of the housing element  46 . 
         [0055]    The pipe section  14  is maintained in the cylinder-shaped recess  38  inside the molded element  40 . The recess  38  in the molded element  40  has a substantially circular cross section, on which respectively right and left lateral areas an expansion cut  80   a  or  80   b  is formed. The expansion cuts  80   a  and  80   b  prevent the molded element  40  from tearing while pressing the high-grade steel pipe section  14  into the recess  38 , or assure the pressure force required for the stable holding of the pipe section  14  in the recess  38 . 
         [0056]    The condensate-vaporizing device represented in  FIGS. 1 to 3  can be installed in accordance with this invention in a cooling device, in particular for a switchgear cabinet.