Abstract:
The disclosure is related to centrifugal water pumps and consists of a union of lateral suction and support covers with the water pump housing by a plurality of non-screwing pressure elements and of an external gasket adjustment mechanism.

Description:
FIELD OF THE INVENTION 
     This invention is related to centrifugal water pumps and consists of a union of lateral covers with the water pump housing by means of non-screwing pressure elements and of an external gasket adjustment mechanism. 
     BACKGROUND OF THE INVENTION 
     All water pumps have covers providing access to the same in such a way that these covers are joined with a housing by means of screws. Water pumps working in different natural conditions, in remote areas, for example used in mining, require frequent disassembly of the covers to eliminate jams or for internal cleaning which is time consuming, especially when covers are joined with the housing by means of screws. After prolonged periods of use, the water pump gaskets suffer wear, causing leaks and requiring an interruption of use for replacement. 
     The present invention provides for the elements which eliminate these inconveniences. The first element allows rapid and easy assembly and disassembly of the lateral covers by eliminating the use of screws to join said covers. The second element allows external adjustment of the gasket and so avoiding leaks. 
     The objective of the present invention is to prolong the smooth functioning of the water pumps and facilitate rapid repair and maintenance in difficult working conditions. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective drawing of the housing and the suction cover which closes the access opening, showing the holding pins of said cover; 
     FIG. 2 is a lateral view of the housing cross-section and the holding pins; 
     FIG. 3 is a front view of the housing with the holding pins, shown as constituent parts; 
     FIG. 4 is a view of the breakdown of a part of the pump external gasket adjustment mechanism; and 
     FIG. 5 is a partial view in a longitudinal section of the part of the external gasket adjustment mechanism and an enlarged detail of this section showing the operation of the mechanism for adjusting the gasket. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIGS. 1 to 4 show a water pump housing which comprises, on its external face opposite the motor connecting shaft (not shown), a circular access opening 2 which is plugged with a suction cover 3 with a bevelled edge 4, which fits into the opening 2. A unit with three L shaped projections 5 with openings 7 and located in the external adjacent surface around the opening 2 and along both opposite faces of the pump, each of which forms a unit containing pins 6 which may be inserted in the said openings 7 of the projections 5. The support cover 3a with a diameter equal to the opposite suction cover 3 has internal hexagonal cavities 21 for the insertion of each screw head which fasten the support of the pump by external nuts. Each of the L shaped projections 5 has a small rear inclination upwards which impedes the backward movement of the respective pin 6 and pressures the cover in the upper region. According to FIG. 5, along the motor connecting side, the pump has a conical body 8 integrally connected with the support cover 3a (see FIG. 2), with a tow guard 10 and with two vertical pins 10a, gaskets 11 and 13 on a coupling 12, and a support ring 14. A moving coupling plate 9 (see FIG. 4) is housed in the central cavity of the coupling 12 by means of a motor connecting shaft. The conical body 8 is comprised, in the surface around the opening for the motor connecting shaft 8a (see FIG. 4), of two opposite equidistant guide arcs 18 and at 90 degrees from these guide arcs 18 there is a threaded pin 17 with nuts 19, parallel to the said surface and extending from it, along which there is an external displaceable bushing 15, with bevelled ends 16, which move in turn with the guide arcs 18. Below these guide arcs 18 are openings 20 to provide access to the pins 10a of the tow guard 10. The functioning of the elements of the invention can be explained as follows: the suction and support covers 3 and 3a with their opposite lateral locations, have bevelled edges 4 which fit with the edges of the openings 2, and when in place allow the passing of the pins 6 along the openings 7 provided in the projections 5 of each lateral region. The insertion of these pins 6 whose ends rest on the external surface of the cover 3, will force bevelled edge 4 to make tight contact with the walls of the opening 2, forming a hermetic seal. The projections 5 in their rear part present a small upward sloping region which force the pin 6 to pressure forward against the cover 3 avoiding a loosening due to vibration of the pump. 
     It will be observed that due to the configuration of the pins 6, for their insertion or removal a tool such as a hammer will be sufficient and their handling will therefore be rapid and simple. 
     The adjustment of the gasket according to this invention is determined by the position of the tow guard 10 with its pins 10a, which project through the openings 20 (see FIG. 5) below the guide arcs 18. Since the bevelled end 16 of the bushing 15 rests on the projection pins 10a, in the guide arcs 18 and that this bushing 15 is movable along the threaded pin 17 by means of the nut 19, upon the tightening of this nut the bevelled ends 16 of the bushing 15 will force, in a cam effect and in a change of direction of the movement, the pins 10a to move along the shaft pressing the gaskets 11 and 13 and making them expand laterally, forming a gasket on the coupling 12 and the walls of the conical body 8. 
     As can be appreciated from what has been shown and due to the fact that the movement of the bushing 15 is uniform throughout and limited to straight movement due to the effect of the guides that the guide arcs 18 and the threaded pin 17 provide on which it moves, the movement transmitted to the pins 10a of the tow guard 10 will also be equally uniform and balanced also exerting uniform pressure on the group of internal gaskets in the conical body 8.