Abstract:
An interchangeable sanitary part ( 1, 10 ) including an outer housing ( 3 ) which can be inserted into a fluid line and has at least one peripheral seal ( 20, 21 ) on its outer circumference, which seals the outer housing ( 3 ) and the fluid line against each other. In order to avoid using additional O-rings, the at least one seal ( 20, 21 ) for providing linear or planar sealing is produced from the same material as the outer housing and forms a single element with the outer circumference of the housing. In another embodiment of the invention, an integratable part is embodied as a backflow preventer, and at least one peripheral sealing lip ( 8 ) forms one element with the inner surface of the outer housing ( 3 ) or the closing part ( 4 ), mounted on the same, and consists of the same material as the surface or closing part. The free end of the sealing lip ( 8 ) protrudes in such a way that, when the backflow preventer ( 10 ) is closed, the lip acts on the closing part ( 4 ) or the inner surface of the outer housing ( 3 ) in a sealing manner.

Description:
BACKGROUND  
         [0001]    The invention relates to an integratable sanitary part with an outer housing, which can be inserted into a fluid line and which carries on the outer circumference of the housing at least one peripheral seal, which seals the outer housing and the fluid line with each other.  
           [0002]    From DE 37 22 665 C2, a check valve is already known, which has a closing part, which can be moved against a valve seat in the outer housing of this check valve against the direction of flow. In order to tightly seal the region between the valve seat and the closing part in the closed position of the known check valve, an O-ring made from elastic material is inserted into a groove on the closing part. The outer housing of the known check valve carries another O-ring made from elastic material, which should seal the outer housing and the adjacent fluid line with each other.  
           [0003]    If such check valves are inserted into sanitary water lines, special certifications are required, which certify that the components are of a quality, e.g., suitable for carrying food. Because many elastomers contain a high percentage of softeners, only a limited selection of elastomers are available for manufacturing the O-ring used in known check valves. In addition, the manufacturing of such check valves also requires a greater expense due to the use of several components made from different materials.  
         SUMMARY  
         [0004]    Therefore, there is the object of creating an integratable sanitary part of the type mentioned in the introduction, which can be produced with low expense and can be used for multiple purposes.  
           [0005]    More specifically, the solution of this objective according to the invention for the integratable sanitary part of the type mentioned in the introduction is to form the one or more seals provided for linear and/or planar sealing on the outer circumference of the housing as an integral piece.  
           [0006]    The integratable part according to the invention has an outer housing that can be inserted into a fluid line, on whose housing outer circumference at least one peripheral seal is formed as an integral piece, which is used for linear and/or planar sealing between the outer housing and fluid line. This seal makes an additional O-ring made from elastic material unnecessary. By eliminating such an O-ring, the cost associated with production and if applicable, also the certification of such an integratable part can be reduced considerably, especially if the sealing is likewise produced from the material also used for the outer housing.  
           [0007]    In this way, for one embodiment according to the invention, at least one seal is formed as a lip seal. In addition or as an alternative, it can be advantageous if at least one seal is configured as a sealing ring formed on the outer housing.  
           [0008]    In order to achieve a load-capable seal between the outer housing and fluid line also for high fluid pressures, it is advantageous if several lip seals and/or sealing rings are formed as integral pieces on the outer housing, which can be arranged with sufficient distance from each other in the intended direction of flow.  
           [0009]    Here, it can be advantageous if the seal(s) are provided in the supply end region or in a center region of the outer housing.  
           [0010]    In order to be able to arrange the outer housing with a force-fit seating in the fluid line and in order to be able to press the seal securely and tightly to the fluid line, it is advantageous if the outer housing has a barrel-shaped or bulging outer outline, at least in part of the peripheral region. In this way, it can be advantageous if the greatest outer extent of the bulging outer housing is arranged somewhat in the middle, relative to the longitudinal extent of the housing, and/or if in the region of the greatest outer extent of the bulging outer housing, there is at least one sealing ring, preferably at least two sealing rings.  
           [0011]    In another solution according to the invention for the objective stated in the introduction, which is worthy of protection in its own right, and which relates to an integratable part configured as a sanitary check valve, at least one peripheral sealing lip is formed as an integral piece on the inner surface of the outer housing or on the closing part, wherein this sealing lip projects with its free lip end such that in the closed position of the check valve, the lip end forms a seal on the closing part or the inner surface of the outer housing.  
           [0012]    This check valve according to the invention, whose outer housing and closing part are formed as plastic injection-molded parts made from thermoplastic or a similar technical plastic, has at least one sealing lip, which is formed on the inner surface of the outer housing or on the closing part as an integral piece. Because these one or more sealing lips are configured as a formation on the outer housing or the closing part, they can also be produced from the same material. Such a sealing lip, which forms a seal in the closed position of the check valve with the closing part or the inner surface, likewise makes an additional O-ring made from elastic material unnecessary. By eliminating this O-ring, the expense associated with the production and, if applicable, the certification of such a check valve can be reduced considerably.  
           [0013]    For an embodiment, in which at least one peripheral sealing lip is provided on the closing part, it is advantageous if a sleeve-shaped housing section with a central flow-through opening is provided in the outer housing, wherein this sleeve-shaped housing section has a truncated cone-shaped outer extent at least in a sleeve-end region projecting into the housing interior and forming the valve seat, and if the lip end of the one or more sealing lips formed on the closing part forms a seal on the truncated cone-shaped outer extent of the sleeve-shaped housing section in the closed position of the check valve. For this refinement according to the invention, the sealing lip widens slightly when it contacts the truncated cone-shaped outer extent of the sleeve-shaped housing section and does not compress in the outer extent, which could alternatively lead to the formation of a fold in the region of the sealing lip and thus to an undesired break in the seal.  
           [0014]    To prevent undesired leakage and similar seal failure in the closed position of the check valve, it is advantageous if the one or more sealing lips form a peripheral, linear contact against the closing part or the inner surface of the outer housing in the closed position of the check valve with its free lip end region.  
           [0015]    In one embodiment according to the invention, the one or more sealing lips extend to form a conical point in cross section in their free lip end region.  
           [0016]    An especially good seal of the valve seat can be achieved if the one or more sealing lips is/are oriented in their longitudinal extent approximately parallel to the longitudinal axis of the check valve. In this way, it is especially advantageous if the partial region of the closing part contacted by the sealing lip is formed as an inclined surface oriented in the flow-through direction from inside to outside. Especially through the combination of these features, the one or more sealing lips form a seal with the closing part inclined to the surface of the closing part.  
           [0017]    To counteract over-extension of the sealing lip in the closed position of the check valve and to achieve high return-pressure stability, it is advantageous if the check valve has at least one stop for the closing part engaged in this closed position.  
           [0018]    It is advantageous if an annular, peripheral partial region of the inner surface of the outer housing is provided as a stop. The sleeve-end region of the sleeve-shaped housing section forming a valve seat in the outer housing of the check valve can be used, e.g., as the stop.  
           [0019]    In the closed position of the check valve, an additional seal can be achieved if the inner surface of the outer housing is formed complementary to the opposite partial region of the closing part in the closed position in its annular, peripheral partial region acting as a stop.  
           [0020]    In this way, in a preferred embodiment according to the invention, the one or more sealing lips and the one or more stops are arranged so that the sealing lips contact the closing part before the stop is engaged.  
           [0021]    It can be advantageous if the one or more sealing lips are formed flexible and elastic at least in their free lip end region. The closing and returning movements of these sealing lips, which are flexible and elastic at least in one partial region, counteracts calcification of the check valve at least in this region.  
           [0022]    To achieve a self-reinforcing sealing effect of the sealing lip, it can be advantageous if a return flow acts on at least one sealing lip, which can be pressed against the closing part.  
           [0023]    A high fatigue strength of the check valve can be supported if the outer housing is produced from a plastic, preferably a structural plastic.  
           [0024]    In this way, in a preferred embodiment according to the invention, the outer housing is produced from a thermoplastic material.  
           [0025]    Obtaining the necessary certifications, e.g., for use in sanitary installations, can be simplified and the manufacturing expense reduced if the outer housing and the closing part are produced from the same material. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0026]    Further features of the invention are found in the following description of preferred embodiments according to the invention in connection with the claims and also the drawing. The individual features can be utilized alone or in combinations to form an embodiment according to the invention.  
         [0027]    Shown are:  
         [0028]    [0028]FIG. 1 is a view of a check valve, which has on the inner surface of the outer housing a peripheral sealing lip, which forms a seal in the closed position of the check valve on the closing part, and  
         [0029]    [0029]FIG. 2 is a view of a check valve also shown in a longitudinal section, which here has on its closing part at the end a peripheral sealing lip, which interacts with the outer truncated cone-shaped sleeve-end region of a sleeve-shaped section of the outer housing forming the valve seat. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0030]    In FIG. 1, two different configurations  1 ,  10  of a check valve are shown in a longitudinal section. While the configuration shown in the left half of FIG. 1 documents the inner structure of the state of the art, an embodiment of the check valve  10  according to the invention is shown in the right half of FIG. 1.  
         [0031]    The check valves  1 ,  10  shown in FIG. 1 are designed to be inserted into a sanitary water line. They feature a valve  2 , which is arranged in a sleeve-shaped outer housing  3 . The valve  2  of the check valve  1 ,  10  has a closing part  4 , which can be moved in the outer housing  3  by the restoring force of a compression spring  5  against the flow-through direction Pf 1  against a valve seat  6 . In this way, the valve seat  6  is formed by a partial region of the inner surface of the outer housing  3 .  
         [0032]    As can be seen from the left side of FIG. 1, the known check valve  1  has an O-ring made from elastic material, which is inserted into a groove  18  on the closing part  4 . Because many elastomers are not suitable for drinking water due to a high percentage of softeners, for various applications, at best only a limited selection of elastomers are available for producing such O-rings. Because the elastic material of the O-rings  7  tends to stick to the valve seat  6  at first, especially after a corresponding contact pressure, the known check valves  1  do not exhibit uniform response behavior for opening and closing. In addition, the known check valves  1  show increased wear and tear in the region of the O-ring  7 .  
         [0033]    Therefore, instead of an O-ring  7 , the check valve  10  according to the invention has a peripheral sealing lip  8 , which is formed as an integral piece in the region of the valve seat  6  on the inner surface of the outer housing  3 . This sealing lip  8  projects with its free lip end  9  into the housing interior such that it forms a seal on the closing part  4  in the closed position of the check valve  10 . The sealing lip  8  is here formed as a pointed lip and extends to a conical point in cross section on its free lip end region. This pointed configuration of the sealing lip  8  guarantees that the sealing lip  8  of the closing part forms a peripheral, linear contact in the closed position of the check valve  10  with its free lip end region.  
         [0034]    The sealing lip  8  oriented in its longitudinal extent with its axis approximately parallel to the longitudinal axis  11  of the check valve  10  contacts the closing part  4  in its partial region  12 , which is formed as an inclined surface arranged in the flow-through direction Pf 1  from inside to outside.  
         [0035]    To counteract over-extension of the sealing lip  8  and to achieve a high return-pressure stability of the check valve  10 , the check valve  10  has a stop  13 , which is here formed by an annular, peripheral partial region of the inner surface of the outer housing  3 .  
         [0036]    In this way, the partial region of the surface acting as the stop  13  is formed complementary to the opposite partial region of the closing part  4  in the closed position. Because the stop  13  contacts the inclined surface  12  of the closing part  4  in the closed position of the check valve  10 , an additional seal can be achieved in this region of the check valve  10 .  
         [0037]    So that the stop  13  can be engaged only for a defined pressure of the return flow, the sealing lip  8  is arranged in the flow-through direction Pf 1  before the stop  13  such that the sealing lip  8  contacts the closing part  4  before the stop  13  is engaged.  
         [0038]    The sealing lip  8  is here configured to be flexible and elastic only in its free lip end region. The closing and returning movements of the flexible and elastic partial region of the sealing lip  8  effectively counteracts calcification of the check valve  10  in this region. The sealing lip  8  projects into the housing interior such that it is charged by a return flow and is pressed against the closing part  4 . The valve  2  of the check valve  10  thus has a self-reinforcing sealing function.  
         [0039]    Because the sealing lip  8  of the check valve  10  is configured as a formation of the outer housing  3 , it can also be produced from the same material. The sealing lip  8 , which in the closed position of the check valve  10  forms a seal on the closing part  4 , makes an additional O-ring made from elastic material unnecessary. By eliminating the O-ring, the expense associated with the production and, if applicable, also the certification of such a check valve can be reduced considerably.  
         [0040]    In this way, it is advantageous if the outer housing  3  with the sealing lip  8  formed thereon and the closing part  4  are produced from the same material. In the embodiment shown here, the components  3 ,  4  of the check valve  10  are produced from a technical thermoplastic or a similar structural plastic, which is here designated generally as thermoplastic.  
         [0041]    In order to be able to also form a good seal for intermediate spaces possibly remaining between the check valve  10  and the adjacent flow line and in order not to also provide an elastic O-ring in this region, in the embodiments described here, on the outside of the outer housing of the check valve, at least one seal is formed from the same material and as an integral piece. The check valve  10  according to the invention can be produced with low expense from only a few components, preferably from the same material, wherein, e.g., the outer housing and the closing part can be produced in a very simple way as plastic injection-molded parts.  
         [0042]    [0042]FIG. 2 shows a different embodiment of the check valve  10  according to the invention. The check valve shown in FIG. 2 has on the supply end of its closing part  4  a peripheral sealing lip  8  projecting in the longitudinal direction of the check valve  10 . In the closed position of the check valve  10 , the sealing lip  8  contacts the inner surface of the outer housing  3  to form a linear seal. For this purpose, in the outer housing  3 , a sleeve-shaped housing section  14  is provided, which has a truncated cone-shaped outer extent in its sleeve end region projecting into the housing interior and forming the valve seat. During the closing movement of the check valve  10 , if the sealing lip  8  contacts the truncated cone-shaped housing section  14 , the one or more sealing lips  8 , which are flexible and elastic at least in their free lip end region, widen slightly and do not compress in their outer extent, which could alternatively lead to the formation of a fold in the region of the sealing lip  8  and thus to undesired breaks in the seal.  
         [0043]    The sealing lip  8  of the check valve  10  shown in FIG. 2 is also oriented in its longitudinal extent approximately axis parallel to the longitudinal axis of the check valve  10  and extends into a conical point in cross section in its free lip end region.  
         [0044]    In FIG. 2, it can be seen that the end of the truncated cone-shaped housing section  14  forming the valve seat acts as a stop for the closing part  4 , which is engaged in the closed position. In this way, the front end of the housing section  14  interacts with an annular shoulder  15 , which is oriented approximately perpendicular to the longitudinal axis of the check valve  10  and which is provided on the outer edge of the supply end of the closing part  4  and which carries the sealing lip  8 . The sealing lip  8  and the front end of the housing section  14  acting as a stop for the closing part  4  are arranged so that the sealing lip  8  contacts the closing part  4  before the front end of the housing section  14  contacts the annular shoulder  15  of the closing part  4 .  
         [0045]    The check valve  10  shown in FIG. 2 otherwise corresponds to the embodiment shown in FIG. 1. The check valve shown in FIG. 2 can also eliminate an O-ring made from elastic material in the region of the valve seat, which considerably reduces the expense associated with production and also certification of such a check valve.  
         [0046]    It is made clear from FIGS. 1 and 2 that the integratable sanitary parts  1 ,  10  shown here can also be sealed in the region between their outer housing  3  and the fluid line without an additional separate O-ring made from elastic material. The integratable sanitary parts  1 ,  10 , which are here configured as check valves, have peripheral seals  20 ,  21  for this purpose, which are formed as an integral piece on the outer circumference of the housing. These seals  20 ,  21  configured as formations of the outer housing  3  are produced from the same material as the outer housing  3 .  
         [0047]    The seals  20 ,  21  of the check valve are arranged at a slight distance from each other in the supply direction Pf 1  and here each provide for a linear seal between the outer housing  3  and fluid line.  
         [0048]    In FIG. 2 it can be seen that the seals of the check valve  10  are configured as lips seals  20 , which are arranged in the supply end region of the check valve. While the upper sealing lip  20  forming the supply end of the check valve is oriented diagonally against the supply direction Pf 1 , the subsequent sealing lips  20  in the supply direction Pf 1  are oriented somewhat in the radial direction.  
         [0049]    In contrast, the check valve  1  shown in FIG. 1 has in the center region of its longitudinal extent several seals  21 , which are formed as peripheral sealing rings  21  on the outer housing  3  as integral pieces. To press the sealing rings  21  tightly against the fluid line, the check valve  1  has a bulging outer outline in this center region, whose greatest outer diameter is preferably approximately equal to or greater than the inner diameter of the fluid line in the line section designed for holding the check valve.  
         [0050]    The seals  20 ,  21  of the check valve  1 ,  10  make an additional O-ring made from elastic material on the outer housing  3  unnecessary. By eliminating such an O-ring, the expense associated with production and, if applicable, certification of such an integratable part can be reduced significantly, especially if the seals  20 ,  21  are likewise produced from the material used for the outer housing  3 .  
         [0051]    Here, it is understood that especially for an integratable part configured as a check valve, the seals  20 ,  21  can be formed on the outer housing and/or the seals described here can be provided on the valve  2 . In as much as it relates to the seals  20 ,  21  formed on the outer housing  3 , these can be provided not only on a check valve, but also on a flow-rate regulator, a jet regulator, or another integratable sanitary part, which can be inserted with its outer housing  3  into a sanitary water or fluid line.