Abstract:
An assembly is disclosed for forming a fluid-tight seal between a pump housing and a seal plate. The housing includes a first flange with a first plurality of apertures formed therein, and the seal plate includes a second flange with a second plurality of apertures formed therein. A gasket is provided between the pump housing and the seal plate. A plurality of inserts extend through the first plurality of apertures, and a plurality of spacers extend through the second plurality of apertures. A plurality of threaded connectors are used to couple the seal plate to the pump housing to form a fluid-tight seal. The dimensions of the inserts and spacers are selected so as to inhibit crushing of the gasket and the flanges when the connectors are fully tightened.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application No. 60/848,074, filed Sep. 29, 2006, which is hereby incorporated by reference in its entirety for all purposes. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to pumps, and more particularly, to pumps with fluid-sealing couplings. 
     BACKGROUND OF THE INVENTION 
     Water pumps incorporate fluid-sealing couplings adapted to retain fluid under pressure during operation of the equipment. Such couplings are also often designed to facilitate disassembly and reassembly of the equipment (e.g., to inspect and replace internal equipment components when the equipment is not in operation). Properly assembled couplings apply a predetermined level of compression on a sealing element (e.g., a gasket) to prevent fluid from leaking out of the coupling. 
     In order to disassemble and properly reassemble conventional pumps, it is frequently necessary to use instructions and/or special tools. In instances where instructions and/or special tools are not provided, or where instructions and/or special tools are provided but not available, the coupling may be reassembled with improper alignment. For example, the application of insufficient torque on one or more coupling bolts, relative to a predetermined level, may result in fluid leakage at the gasket adjacent to any under-tightened bolt. Likewise, the application of too much torque on one or more housing bolts, relative to a predetermined level, may result in damage to the seal of the coupling (e.g, a crushed or crimped gasket). 
     SUMMARY OF THE INVENTION 
     The present invention provides a fluid-sealing coupling that can be dissembled and subsequently completely reassembled, readily and reliably in proper alignment, without the use of specialized tools or instructions. The fluid-sealing coupling includes first and second ends, each having at least one sealing surface positioned thereon. The coupling also includes a seal, such as a gasket, which is interposed between the sealing surfaces of the first and second ends so as to retain fluids within the coupling. More particularly, a plurality of inserts, each having an alignment surface formed thereon, are positioned in a plurality of recesses located on the first end. Likewise a plurality of spacers, each having an alignment surface formed thereon, are positioned in a plurality of recesses which are located on the second end. When connectors, such as bolts, position the respective alignment surfaces of the inserts and spacers such that they are in contact with each other, the coupling is properly assembled. 
     The present invention is therefore particularly useful for users who are inexperienced in the disassembly and assembly of fluid-sealing couplings. The features and advantages of the invention will appear more clearly on a reading of the detailed description of the exemplary embodiments of the invention, which is given below by way of example only and with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a better understanding of the present invention, reference is made to the following detailed description of an exemplary embodiment considered in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a pump constructed in accordance with an exemplary embodiment of a pump housing coupling of the present invention; 
         FIG. 2  is an exploded perspective view of the pump shown in  FIG. 1 , portions of the pump being broken away to facilitate discussion of the pump housing coupling of the present invention; 
         FIG. 3  is a rear perspective view of a seal plate employed by the pump shown in  FIGS. 1 and 2 ; 
         FIG. 4  is a perspective view of an insert; 
         FIG. 5  is a side elevational view of the insert shown in  FIG. 4 ; 
         FIG. 6  is a is a cross-sectional view, taken along section line  6 - 6  of  FIG. 5 , of the insert shown in  FIG. 5 ; 
         FIG. 7  is a perspective view of a spacer; 
         FIG. 8  is a side elevational view of the spacer shown in  FIG. 7 ; 
         FIG. 9  is a is a cross-sectional view, taken along section line  9 - 9  of  FIG. 8 , of the spacer shown in  FIG. 8 ; and 
         FIG. 10  is a cross-sectional view, taken along section line  10 - 10  of  FIG. 1  and looking in the direction of the arrows, of a portion of the pump shown in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIGS. 1-3 , a pump  10  includes a pump housing  12  and a seal plate  14 , which is removably attached to the pump housing  12 . The pump housing  12  and the seal plate  14  are preferably constructed from glass fiber polypropylene, although other suitable materials may be utilized. An electric motor (not shown) is removably attached to the seal plate  14  and coupled to an impeller (not shown) within the pump housing  12 . The pump  10  circulates fluid in a fluid circulating system. For example, the pump  10  circulates water in a swimming pool, spa, or whirlpool. 
     With particular reference to  FIG. 2 , the pump housing  12  includes a flange  16  formed about an opening  18  at a first end  20  of the pump housing  12 . The flange  16  includes a first surface  22  and an opposing second surface  24 , which is adjacent the seal plate  14  when the seal plate  14  is attached to the pump housing  12 . The flange  16  has a width W 1  between the first surface  22  and the second surface  24 . A sealing surface  26  is formed along the inner periphery of the second surface  24 . The sealing surface  26  is oriented at an angle (e.g., 45 degrees) relative to the second surface  24  of the pump housing  12 . The flange  16  includes a plurality of square-shaped apertures  28 , each having a width W 2 . 
     Referring to  FIGS. 2-3 , the seal plate  14  includes a flange  30  having a first surface  32  and an opposing second surface  34 , which is adjacent the pump housing  12  when the seal plate  14  is attached to the pump housing  12 . The flange  30  has a width W 3  between the first surface  32  and the second surface  34 . The flange  30  includes a plurality of circle-shaped apertures  36 , each having a diameter D 1 . The circle-shaped apertures  36  of the flange  30  are adjacent the square-shaped apertures  28  of the flange  16 , when the seal plate  14  is attached to the pump housing  12 . 
     With particular reference to  FIG. 3 , the seal plate  14  includes a first sealing surface  38  that is disposed about the inner periphery of the second surface  34 . The seal plate  14  further includes a second sealing surface  40  that is substantially perpendicular to the first sealing surface  38 . 
     Referring now to  FIGS. 4-6 , an insert  42  has a first end  44  and an opposing second end  46 . The insert  42  is formed from sintered bronze, although other suitable materials may be used. The insert  42  includes a circle-shaped head  48  having a first surface  50 , which is formed at the second end  46  of the insert  42 , and an opposing second surface  52 . The circle-shaped head  48  has diameter D 2 , which is larger than the width W 2  of the square-shaped apertures  28  of the flange  16 . 
     The insert  42  further includes a square-shaped shank  54  that extends from the second surface  52  of the circle-shaped head  48  to the first end  44  of the insert  42 . The square-shaped shank  54  includes an alignment surface  56  formed at the first end  44  of the insert  42 . A boring  58  is formed within the insert  42 . The boring  58  extends from the first end  44  through the square-shaped shank  54  and the circle-shaped head  48  to the second end  46  of the insert  42 . The boring  58  has threads  60  formed therein. 
     The square-shaped shank  54  has a length L 1  as measured from the second surface  52  of the circle-shaped head  48  to the first end  44  of the insert  42 . The length L 1  of the square-shaped shank  54  is less than the width W 1  of the flange  16 . The square-shaped shank  54  has a width W 4 , which is slightly smaller that the width W 2  of the square-shaped apertures  28 . 
     Referring now to  FIGS. 7-9 , a spacer  62  has a first end  64  and an opposing second end  66 . The spacer  62  is formed from sintered bronze, although other suitable materials may be used. The spacer  62  includes a circle-shaped head  68  having a first surface  70  and an opposing second surface  72 . The first surface  70  of the circle-shaped head  68  is formed at the second end  66  of the spacer  62 . The circle-shaped head  68  of the spacer  62  has a diameter D 3 , which is larger than the diameter D 1  of the circle-shaped apertures  36 . 
     The spacer  62  includes a circle-shaped shank  74  that extends from the second surface  72  of the circle-shaped head  68  to the first end  64  of the spacer  62 . The spacer  62  further includes a boring  76  that extends from first end  64  through the circle-shaped shank  74  and the circle-shaped head  68  to the second end  66  of the spacer  62 . The boring  76  has a diameter D 4 . The circle-shaped shank  74  includes an alignment surface  78  formed at the first end  64  of the spacer  62 . 
     The circle-shaped shank  74  has a plurality of teeth  80  formed thereon. The circle-shaped shank  74  has a length L 2  as measured from the second surface  72  of the circle-shaped head  68  to the first end  64  of the spacer  62 . The length L 2  of the circle-shaped shank  74  is greater than the width W 3  of the flange  30 . 
     Referring to  FIG. 2 , the pump  10  includes a gasket  82  disposed between the pump housing  12  and the seal plate  14 . The gasket  82  is formed from a resilient elastomeric material such as ethylene propylene diene monomer, although other suitable materials may be utilized. 
     The seal plate  14  is attached to the pump housing  12  with a plurality of connectors  84 , each having a first end  86  and an opposing second end  88 . Each connector  84  includes a circle-shaped head  90  having a first surface  92  and an opposing second surface  94 . The circle-shaped head  90  includes a hexagon-shaped portion  96  formed at the second end  88  of the connector  84  and extending to the first surface  92  of the circle-shaped head  90 . The circle-shaped head  90  has a diameter D 5 , which is larger than the diameter D 4  of the borings  76  of the spacers  62 . 
     Each connector  84  further includes a circle-shaped shank  98  that extends from the second surface  94  of the circle-shaped head  90  to the first end  86  of the connector  84 . The circle-shaped shank  98  includes a plurality of threads  100  formed thereon. The connectors  84  are formed from stainless steel, although other suitable materials may by used. 
     Still referring to  FIG. 2 , a procedure for assembling the pump  10  to form a fluid-tight seal (not shown) between the pump housing  12  and the seal plate  14  will now be described in detail. The gasket  82  is placed on the seal plate  14  so as to contact the first sealing surface  38  and the second sealing surface  40 . The structure of the first sealing surface  38  and the second sealing surface  40  holds the gasket  82  in place for the remainder of the assembly procedure. 
     Referring now to  FIGS. 1-9 , each of a plurality of the inserts  42  is inserted into one of the plurality of the square-shaped apertures  28  in the flange  16 . More particularly, the first ends  44  of the inserts  42  are inserted into the square-shaped apertures  28  in the flange  16  and are advanced until the second surfaces  52  of the circle-shaped heads  48  abut the first surface  22  of the flange  16 . As previously noted, the diameter D 2  of the circle-shaped heads  48  of the inserts  42  is larger than the width W 2  of the square-shaped apertures  28 , which prevents the circle-shaped heads  48  from passing through the square-shaped apertures  28 . 
     Similarly, each of a plurality of the spacers  62  is fully inserted into one of the plurality of the circle-shaped apertures  36  in the flange  30 . More particularly, the first ends  64  of the spacers  62  are inserted into the circle-shaped apertures  36  and are advanced until the second surfaces  72  of the circle-shaped heads  68  of the spacers  62  abut the first surface  32  of the flange  16 . 
     A force (not shown) of sufficient magnitude is preferably applied to the first surfaces  70  of the circle-shaped heads  68  of the spacers  62  to fully advance the teeth  80  of the circle-shaped shanks  74  into the circle-shaped apertures  36  of the flange  30 . The spacers  62  are formed from sintered bronze, which is more rigid than glass fiber polypropylene, from which the seal plate  14  is formed. Thus, the dimensions of the teeth  80  should not be so large as to cause damage to the seal plate  14  as the circle-shaped shanks  74  of the spacers  62  are inserted into the circle-shaped apertures  36  of the flange  30 . 
     When the spacers  62  are fully inserted into the circle-shaped apertures  36 , the teeth  80  ensure that spacers  62  become securely attached to the seal plate  14 . As a result, the spacers  62  will not fall out of the circle-shaped apertures  36  of the seal plate  14  as the remainder of the assembly procedure is performed. Moreover, the first ends  64  of the spacers  62  protrude from the second surface  34  of the flange  30  (see  FIG. 10 ), when the spacers  62  are fully inserted into the circle-shaped apertures  36 . The protruding circle-shaped shanks  74  are substantially perpendicular the second surface  34  of the flange  30 . 
     The seal plate  14  is then positioned near the pump housing  12  and the circle-shaped apertures  36  of the flange  30  are aligned with the square-shaped apertures  28  of the flange  16 . After proper alignment, the seal plate  14  is advanced toward the pump housing  12 . 
     The seal plate  14  is then attached to the pump housing  12  with the plurality of connectors  84 . The first end  86  of one of the connectors  84  is inserted into a boring  76  of one of the spacers  62  and advanced until the first end  86  contacts the boring  58  of the corresponding insert  42 . A technician (not shown) uses a wrench (not shown) to apply a torque (not shown) to the hexagon-shaped portion  96  of the connector  84 , thereby rotating the connector  84 . The applied torque advances the threads  100  of the connector  84  into the threads  60  of the boring  58  of the square-shaped shank  54 . The square-shaped shank  54  is prevented from rotating by the square-shaped aperture  28  of the flange  16 ; thus, only a single wrench is required to assemble the pump  10 . Torque is applied until the technician notices that significantly more torque is required to advance the connector  84 . At this point, the connector  84  is fully tightened, as the alignment surface  56  of the square-shaped shank  54  of insert  42  firmly contacts the alignment surface  78  of the circle-shaped shank  74  of the spacer  62  (see  FIG. 10 ). The torque application procedure is then repeated for all remaining connectors  84 . 
     Referring now to  FIG. 10 , a pump housing coupling  102  is shown. The seal plate  14  is attached to the pump housing  12  such that a liquid-tight seal (not labeled) is formed by the gasket  82  between the sealing surface  26  of the pump housing  12  and the first and second sealing surfaces  38 ,  40  of the seal plate  14 . The connector  84  has been fully tightened, as described above, ensuring that the alignment surface  78  of the spacer  62  firmly contacts the alignment surface  56  of the insert  42 . The circle-shaped shank  74  of the spacer  62  extends into the square-shaped aperture  28  (not labeled) of the flange  16 , which makes the pump housing coupling  102  very rigid. For example, if the pump  10  is dropped, damage to the pump housing couplings  102  is less likely to result, because the circle-shaped shanks  74  of the spacers  62  extends into the square-shaped apertures  28  and the alignment surfaces  78  of the spacers  62  firmly contact the alignment surfaces  56  of the inserts  42 , which increases the rigidity of the pump housing coupling  102 . 
     The insert  42  and the spacer  62  are formed from sintered bronze, which is more rigid than glass fiber polypropylene, from which the pump housing  12  and seal plate  14  are formed. Thus, the pump housing  12  and seal plate  14  could be damaged by applying too much torque to the connector  84 . For example, if the length L 1  of the square-shaped shank  54  of the insert  42  is one-half of the width W 1  of the flange  16  and the length L 2  of the circle-shaped shank  74  of the spacer  62  is one-half of the width W 3  of the flange  30 , then the alignment surface  56  of the insert  42  would not meet the alignment surface  78  of the spacer  62 . 
     However, the flange  16  and the flange  30  are prevented from being damaged by applying too much torque to the connector  84  by choosing appropriate dimensions for the length L 1  of the square-shaped shank  54 , the length L 2  of the circle-shaped shank  74 , the width W 1  of the flange  16 , and the width W 3  of the flange  30 . In addition, the angled orientation of the sealing surface  26  of the pump housing  12  helps to prevent the gasket  82  from being crushed between the sealing surface  26  of the pump housing  12  and the sealing surfaces  38 ,  40  of the seal plate  14 . 
     If the need arises to disassemble the pump  10 , e.g., for maintenance, the pump  10  can be disassembled by a procedure that is the reverse of the aforesaid assembly procedure. Following such disassembly, the pump  10  may be reassembled by repeating the aforesaid assembly procedure. There is no need to replace the gasket  82  because of the structure of the pump housing coupling  102  prevents the gasket  82  from being damaged during the assembly procedure. 
     Some embodiments of the present invention have sealing surfaces  26  that are arranged at orientations other than forty-five degrees relative to the second surface  24  of the flange  16 . In some embodiments of the present invention, the gasket  82  is coated with an appropriate lubricant prior to being placed on the seal plate  14 . 
     In some embodiments of the present invention, teeth are formed on the square-shaped shanks  54  of the inserts  42 , the length L 1  of the square-shaped shanks  54  of the inserts  42  is greater than the width W 1  of the flange  16 , and the length L 2  of the circle-shaped shanks  74  of the spacers  62  is less than the width W 1  of the flange  16 . In some embodiments of the present invention, the length L 1  of the square-shaped shanks  54  of the inserts  42  is slightly less than the width W 1  of the flange  16  and the length L 2  of the circle-shaped shanks  74  of the spacers  62  is slightly less than the width W 3  of the flange  30 . 
     Some embodiments of the present invention include spacers  62  having circle-shaped shanks  74  with structures other than teeth formed thereon, which ensure that the spacers  62  are securely attached to the flange  30 , when the spacers  62  are fully inserted into the circle-shaped apertures  36  of the flange  30 . In some embodiments of the present invention, the flange  30  includes square-shaped apertures  36  formed therein and the spacers  62  have square-shaped shanks  74 . Further, some embodiments of the present invention include connectors  84  having circle-shaped portions  96  with one or more indentations for receiving the tip of a screwdriver. 
     The present invention may also be adapted to other fluid sealing couplings, such as those employed, for instance, with releasable pipe couplings. It is understood that the embodiments of the present invention described herein are merely exemplary and that a person skilled in the art may make many variations and modifications without departing from the spirit and scope of the invention. All such variations and modifications, including those discussed above, are intended to be included within the scope of the invention as defined in the appended claims.