Abstract:
A pump arrangement, in particular a magnetic coupling pump arrangement, includes a pump housing having an interior, a split case which hermetically seals a chamber surrounded by the split case from the interior formed by the pump housing, an impeller shaft with an impeller thereon which can be driven in a rotatable manner about a rotational axis, an inner rotor arranged at an end of the impeller shaft opposite the impeller end, an outer rotor which interacts with the inner rotor, and an adapter element which connects the split case to the pump housing or to a component paired with the pump housing, in particular a housing cover. The adapter element includes a mounting flange which rests against a support surface of the pump housing, in particular of the housing cover ( 4 ), on a face adjacent to the interior.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of PCT International Application No. PCT/EP2014/060197, filed May 19, 2014, which claims priority under 35 U.S.C. §119 from German Patent Application No. 10 2013 008 795.3, filed May 24, 2013, the entire disclosures of which are herein expressly incorporated by reference. 
     
    
     BACKGROUND AND SUMMARY OF THE INVENTION 
       [0002]    The invention relates to a pump arrangement, in particular a magnetic clutch pump arrangement, having an interior space formed by a pump casing of the pump arrangement, having a containment can which hermetically seals off a chamber surrounded by said containment can with respect to the interior space formed by the pump casing, having an impeller shaft which can be driven in rotation about an axis of rotation, having an impeller which is arranged on one end of the impeller shaft, having an inner rotor arranged on the other end of the impeller shaft, and having an outer rotor which interacts with the inner rotor. 
         [0003]    A pump arrangement of said type is known from German patent publication no. DE 10 2004 003 400 A1. In order to increase the range of use, this pump arrangement has a drive rotor formed as an identical part for outer drive elements. This however permits an increase in the range of use only to a particular degree. Above a certain structural size, an adaptation of the rotor size is unavoidable. 
         [0004]    European patent publication no. EP 0 814 268 A1 has disclosed a modular construction kit for producing pumps, which modular construction kit is intended to afford the possibility of producing pumps in any desired manner from a small number of structural elements in accordance with the usage requirements. The proposed solution however permits only an exchange of components associated with a single structural size. 
         [0005]    The documents cited above however do not take into consideration that, owing to different rotational speeds, delivery heights, delivery volumes and densities of the medium to be delivered, a large range of torques is required for a given hydraulic size. 
         [0006]    It is an object of the invention to provide a magnetic clutch pump arrangement in which as large as possible a number of magnetic clutches with different diameters is available for one hydraulic size, and the greatest possible number of different hydraulic sizes can be used for one magnetic clutch size. It is likewise the intention for different containment cans, that is to say different pressure stages and/or materials, to be able to be used within one magnetic clutch size. 
         [0007]    This object of the invention is achieved by an adapter element which connects the containment can to the pump casing or to a component assigned to the pump casing, in particular to a casing cover, the adapter element having a mounting flange which, at the side close to the interior space, bears against an abutment surface of the pump casing, in particular of the casing cover. 
         [0008]    Through the use of different adapter elements, a modular construction kit is made available which permits efficient structural size configuration for one hydraulic size with different magnetic clutch sizes, or for one magnetic clutch size and different hydraulic sizes. 
         [0009]    It is thus possible in a simple manner, by adaptation of the adapter element in terms of shape and/or size, to adapt a magnetic clutch size to different hydraulic sizes. The large range of torques required for the same hydraulic size owing to different rotational speeds, delivery heights, delivery volumes and densities of the medium to be delivered is covered in this way. It is no longer necessary to use the maximum clutch size for all combinations; rather, it is possible in each case for the suitable magnetic clutch size to be adapted to a hydraulic size, with corresponding advantages with regard to energy efficiency, eddy current losses and/or procurement costs. A further advantage of the invention is the reduced number of components that have to be stocked for a pump type series. 
         [0010]    In a further refinement, the abutment surface has a region which is recessed in an axial direction and into which a centering ring formed on the mounting flange engages. It is firstly possible for a seal ring to be arranged in the recessed region, and secondly, the adapter element can be aligned exactly and fastened in fluid-tight fashion to the casing cover. 
         [0011]    By virtue of the fact that, on the side situated opposite the mounting flange, the adapter element has multiple threaded holes for the fastening of the containment can, it is possible, within one magnetic clutch size, to use or interchange different containment cans of different pressure stages or strengths and/or different materials. 
         [0012]    According to the invention, on the side situated opposite the mounting flange, a ring is provided which extends further in the axial direction into the interior space, which ring forms a run-on safeguard and prevents contact between the outer rotor and the containment can. 
         [0013]    To improve the flow guidance of the medium, and for easier and thus cheaper production by casting, the outer contour of the adapter element has a substantially conical profile. 
         [0014]    Here, the adapter element preferably narrows, substantially proceeding from the mounting flange toward the ring. 
         [0015]    In a further refinement, it is provided that that end of the outer rotor which points in the direction of the casing cover has a radially encircling projection. In this way, the radial spacing of the outer rotor to the ring for normal operation can be produced in an exact manner. 
         [0016]    For the same reason, alternatively or in addition, the projection may be formed on the inner side of the ring. 
         [0017]    In a further exemplary embodiment of the invention, it is provided that the end of the outer rotor which points in the direction of the casing cover has a region of reduced outer diameter. The mounting capability of the adapter element in the case of small clutch diameters is thus ensured. 
         [0018]    In a further advantageous refinement, between the impeller and inner rotor, there is arranged a bearing arrangement which is operatively connected to the impeller shaft, which can be driven rotatably about the axis of rotation. 
         [0019]    In the context of the invention, it is proposed that, in a further embodiment, a spring device is arranged between the inner rotor and the bearing arrangement. 
         [0020]    According to the invention, in one embodiment, between the spring device and the inner rotor, there is situated a spacer sleeve, which is pushed onto the impeller shaft and by means of which the inner rotor extends deeper into the outer rotor in an axial direction. Thus, the magnets of the inner rotor and the magnets of the outer rotor are optimally aligned with respect to one another in order to ensure an optimum transmission of power from the outer rotor to the inner rotor. 
         [0021]    Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]      FIG. 1  shows the longitudinal section through a magnetic clutch pump arrangement in accordance with an embodiment of the invention, 
           [0023]      FIG. 2  shows the longitudinal section through the magnetic clutch pump arrangement as per  FIG. 1  with an adapter element according to an embodiment of the invention, 
           [0024]      FIG. 3  shows the longitudinal section through the magnetic clutch pump arrangement as per  FIG. 1  with a further adapter element according to an embodiment of the invention, 
           [0025]      FIG. 4  shows the longitudinal section through a magnetic clutch pump arrangement with a casing cover which serves as a heat barrier, and with an adapter element according to the invention in  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0026]      FIG. 1  shows a pump arrangement  1  in the form of a magnetic clutch pump arrangement. The pump arrangement  1  has a multi-part pump casing  2  of a centrifugal pump, which pump casing comprises a hydraulics casing  3  in the form of a spiral casing, a casing cover  4 , a bearing carrier cage  5 , a bearing carrier  6  and a bearing cover  7 . 
         [0027]    The hydraulics casing  3  has an inlet opening  8  for the intake of a delivery medium and has an outlet opening  9  for the discharge of the delivery medium. The casing cover  4  is arranged on that side of the hydraulics casing  3  which is situated opposite the inlet opening  8 . The bearing carrier cage  5  is fastened to that side of the casing cover  4  which is averted from the hydraulics casing  3 . The bearing carrier  6  is mounted on that side of the bearing carrier cage  5  which is situated opposite the casing cover  4 . The bearing cover  7  in turn is fastened to that side of the bearing carrier  6  which is averted from the bearing carrier cage  5 . 
         [0028]    A containment can  10  is fastened to that side of the casing cover  4  which is averted from the hydraulics casing  3 , and said containment can extends at least partially through an interior space  11  delimited by the pump casing  2 , in particular by the casing cover  4 , by the bearing carrier cage  5  and by the bearing carrier  6 . The containment can  10  has a substantially cylindrical main body  12 . The main body  12  is open on one side and is closed by way of a domed base  13  on the side situated opposite the open side. At the open side there is arranged a ring-shaped fastening flange  14  which is formed integrally with the main body  12  or which is connected to said main body by welding or by way of other suitable fastening means or devices, for example screws, rivets or the like. The fastening flange  14  bears, at the side close to the interior space  11 , against an abutment surface  15  of the casing cover  4 , and has multiple installation holes  16  through which screws  17  can be passed and screwed into threaded bores  18  provided in the casing cover  4 . The containment can  10  hermetically seals off a chamber  19 , which is enclosed by said containment can and by the casing cover  4 , with respect to the interior space  11 . 
         [0029]    An impeller shaft  20  which is rotatable about an axis of rotation A extends from a flow chamber  21 , which is delimited by the hydraulics casing  3  and by the casing cover  4 , into the chamber  19  through an opening  22  provided in the casing cover  4 . An impeller  23  is fastened to a shaft end, situated within the flow chamber  21 , of the impeller shaft  20 , and an inner rotor  24  arranged within the chamber  19  is provided on the opposite shaft end, which has two shaft sections  20   a,    20   b  with increasing diameters in each case. The inner rotor  24  is equipped with multiple magnets  25  which are arranged on that side of the inner rotor  24  which faces toward the containment can  10 . 
         [0030]    Between the impeller  23  and the inner rotor  24  there is arranged a bearing arrangement  26  which is operatively connected to the impeller shaft  20 , which can be driven in rotation about the axis of rotation A. A bearing ring carrier  27 , which is arranged coaxially with respect to the axis of rotation A and by means of which the static parts, that is to say the parts which do not rotate with the impeller shaft  20 , of the bearing arrangement  26  are held in place, bears by way of a flange-like region  28  against a further abutment surface  29  of the casing cover  4 , is fastened by way of a screw connection (not illustrated) to the casing cover  4 , and extends into the chamber  19 . 
         [0031]    Between the inner rotor  24  or the shaft section  20   a  and the bearing arrangement  26 , in particular those parts of the bearing arrangement  26  which rotate with the impeller shaft  20 , there is arranged a spring device  30  in the form of a plate spring pack, which spring device exerts a spring force on the clamped assembly composed of impeller  23 , an impeller nut  32  which fastens the impeller  23  to the impeller shaft  20  via a disk  31 , those parts of the bearing arrangement  26  which rotate with the impeller shaft  20 , and the inner rotor  24 , in such a way that the clamped assembly is held in abutment, in particular by way of the inner rotor  24 , with a certain degree of elasticity against an abutment surface  33  which arises owing to the different diameters of the shaft sections  20   a  and  20   b,  wherein the diameter of the shaft section  20   b  is greater than the diameter of the shaft section  20   a.  The clamped assembly thus comprises substantially the components which rotate with the impeller shaft  20  about the axis of rotation A. 
         [0032]    A drive motor, preferably an electric motor, which is not illustrated drives a drive shaft  34 . The drive shaft  34 , which can be driven about the axis of rotation A, is arranged substantially coaxially with respect to the impeller shaft  20 . The drive shaft  34  extends through the bearing cover  7 , through the bearing carrier  6 , and at least partially into the bearing carrier cage  5 . The drive shaft  34  is mounted in two ball bearings  35 ,  36  which are accommodated in the bearing carrier  6 . On the free end of the drive shaft  34  there is arranged an outer rotor  38 , which bears multiple magnets  37 . The magnets  37  are arranged on that side of the outer rotor  38  which faces toward the containment can  10 . The outer rotor  38  extends at least partially over the containment can  10  and interacts with the inner rotor  24  such that the rotating outer rotor  38 , by way of magnetic forces, sets the inner rotor  24  and thus likewise the impeller shaft  20  and the impeller  23  in rotation. 
         [0033]      FIG. 2  shows a pump arrangement  1 , the outer dimensions of which correspond to the outer dimensions shown in  FIG. 1 . In accordance with a construction kit principle, the hydraulics casing  3 , casing cover  4 , bearing carrier cage  5 , bearing carrier  6  and bearing  7  are thus of the same dimensions. Furthermore, in both embodiments, the impeller  23 , bearing arrangement  26  and bearing ring carrier  27  are of the same dimensions. In the embodiment shown in  FIG. 2 , both the diameter and axial extent of containment can  10 , inner rotor  24  and outer rotor  38  are smaller than in the embodiment shown in  FIG. 1 . This is particularly advantageous if lower power demands, for example a lower delivery height or delivery flow rate, with the highest possible efficiency, are placed on the pump arrangement  1 . 
         [0034]    To adapt the containment can  10  with reduced axial extent and reduced diameter, a separate adapter element  39  is provided which, on one side, has a mounting flange  40 , the design of which substantially corresponds to the design of the fastening flange  14  of the containment can  10  as shown in  FIG. 1 . At the side close to the interior space  11 , the mounting flange  40  bears against the abutment surface  15  of the casing cover  4  and has multiple installation holes  41 , through which the screws  17  can be passed and screwed into threaded bores  18  provided in the casing cover  4 . The abutment surface  15  has a region  42  which is recessed in an axial direction and in which a seal ring  43  is arranged and into which a centering ring  44  formed on the mounting flange  40  engages, whereby the adapter element  39  can be fastened in an exactly aligned and fluid-tight manner to the casing cover  4 . 
         [0035]    On the side situated opposite the mounting flange  40 , the adapter element  39  has multiple threaded holes  45  into which there can be screwed screws  46  which extends through the installation holes  16  in the fastening flange  14  of the containment can  10 . It is thereby possible, within a magnetic clutch size, to interchange different containment cans  10  of different pressure stages or strengths and/or different materials. Furthermore, on the side situated opposite the mounting flange  40 , there is provided a ring  47  which extends further in an axial direction into the interior space  11 , which ring forms a run-on safeguard and prevents contact between the magnets  37  of the outer rotor  38  and the main body  12  of the containment can  10 . The outer contour of the adapter element  39  has in each case a substantially conical profile. Here, proceeding substantially from the mounting flange  40 , the adapter element  39  narrows toward the ring  47 . The inner contour of the adapter element  39  is at least partially of narrowing form. In the embodiment illustrated in  FIG. 2 , that end of the outer rotor  38  which points in the direction of the casing cover  4  has a radially encircling projection  48  facing toward the ring  47 , which projection, in the possible case of an outer rotor  38  rotating with an imbalance, makes contact firstly with the inner side of the ring  47  of the adapter element  39  before the magnets  37  of the outer rotor  38  come into contact with the main body  12  of the containment can  10 . In an alternative embodiment, the projection  48  may also be formed on the inner side of the ring  47 . In a further embodiment, the projection  48  may be formed both on the end of the outer rotor  38  and on the inner side of the ring  47 . 
         [0036]    Between the spring device  30  and the inner rotor  24  there is situated a spacer sleeve  49  which is pushed onto the impeller shaft  20 , and which expands the above-described clamped assembly by this component. In the embodiment shown, the impeller shaft  20 , in particular shaft section  20   a,  is lengthened in relation to the embodiment shown in  FIG. 1  by the length of the spacer sleeve  49 . By means of the spacer sleeve  49 , the inner rotor  24  extends deeper into the outer rotor  38  in the axial direction. In this way, the magnets  25  of the inner rotor  24  and the magnets  37  of the outer rotor  38  are optimally aligned with respect to one another in order to ensure an optimum transmission of power from the outer rotor  38  to the inner rotor  24 . 
         [0037]      FIG. 3  shows a pump arrangement  1 , the outer dimensions of which correspond to the outer dimensions shown in  FIGS. 1 and 2 . Likewise, the impeller  23 , bearing arrangement  26  and bearing ring carrier  27  are of the same dimensions as in the embodiment shown in  FIGS. 1 and 2 . In the embodiment shown in  FIG. 3 , both the diameter and the axial extent of the containment can  10 , inner rotor  24  and outer rotor  38  have been reduced further in relation to the embodiment shown in  FIG. 2 . The impeller shaft  20 , in particular shaft section  20   a,  has the same axial extent as in the embodiment shown in  FIG. 2 . That end of the outer rotor  38  which points in the direction of the casing cover  4  has a region  50 , facing toward the ring  47 , of reduced outer diameter, wherein an outer rotor  38 , in the possible event of it rotating with an imbalance, comes into contact with the inner side of the ring  47  of the adapter element  39  by way of said region  50  first, before the magnets  37  of the outer rotor  38  come into contact with the main body  12  of the containment can  10 . 
         [0038]    As can be seen from  FIG. 4 , the adapter element  39  may also be used on a casing cover  4 , formed as a heat barrier, in a pump arrangement  1  which conducts a hot medium. Here, the hydraulics casing  3 , major regions of the casing cover  4 , the bearing carrier cage  5 , the bearing carrier  6  and the bearing cover  7  are of the same dimensions as in the exemplary embodiments shown in  FIGS. 1 to 3 . The containment can  10 , the adapter element  39  and the outer rotor  38  are of the same dimensions, correspondingly to the magnetic clutch size as per  FIG. 2 . 
         [0039]    The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof. 
       List of Reference Designations 
       [0000]    
       
           1  Pump arrangement 
           2  Pump casing 
           3  Hydraulics casing 
           4  Casing cover 
           5  Bearing carrier cage 
           6  Bearing carrier 
           7  Bearing cover 
           8  Inlet opening 
           9  Outlet opening 
           10  Containment can 
           11  Interior space 
           12  Main body 
           13  Base 
           14  Fastening flange 
           15  Abutment surface 
           16  Installation hole 
           17  Screw 
           18  Threaded bore 
           19  Chamber 
           20  Impeller shaft 
           20   a  Shaft section 
           20   b  Shaft section 
           21  Flow chamber 
           22  Opening 
           23  Impeller 
           24  Inner rotor 
           25  Magnet 
           26  Bearing arrangement 
           27  Bearing ring carrier 
           28  Flange-like region 
           29  Abutment surface 
           30  Spring device 
           31  Disk 
           32  Impeller nut 
           33  Abutment surface 
           34  Drive shaft 
           35  Ball bearing 
           36  Ball bearing 
           37  Magnet 
           38  Outer rotor 
           39  Adapter element 
           40  Mounting flange 
           41  Installation hole 
           42  Recessed region 
           43  Seal ring 
           44  Centering ring 
           45  Threaded hole 
           46  Screw 
           47  Ring 
           48  Projection 
           49  Spacer sleeve 
           50  Region of reduced outer diameter 
         A Axis of rotation