Abstract:
Multi-port valve assemblies with, typically, two-piece housings are disclosed. Particularly useful in connection with swimming pools and associated water pumps, the assemblies avoid reliance on an elongated handle to effect rotation of the internal structure of the valve. Instead, the assemblies utilize a knob—which users need not lift—coupled to a post in which an elongated slot is formed. Doing so avoids breakage problems associated with use of elongated handles while reducing wear of internal seals. Each valve assembly additionally may include a cam having non-semicircular, asymmetrically-shaped recesses into which followers attached to a shaft passing through the elongated slot are received.

Description:
FIELD OF THE INVENTION 
     This invention relates to a valve and more particularly to a multi-position valve assembly especially, although not exclusively, adapted for use in connection with swimming pools and associated water pumps. 
     BACKGROUND OF THE INVENTION 
     U.S. Pat. No. 4,470,429 to Johnson describes an exemplary multi-port valve for use in the care and treatment of swimming pools. The two- and three-way valves of the Johnson patent include a unitary housing and a lever arm splined onto the stub of a shaft. Rotating the lever arm causes a “valve closure sealing surface” of a “closure plug” to move within the structure between various of the hubs or ports. According to the Johnson patent, the sealing surface carries both a “seal member” and an “arcuate retainer plate,” the latter of which is attached to the closure plug using screws. Because the housing is unitary and the fluid passageways extend radially from it, the closure plug need never be lifted from any seated position. 
     U.S. Pat. No. 3,640,310 to Erlich, incorporated herein in its entirety by this reference, discloses another multi-port valve in which one or more inlet ports direct pressurized fluid through an “open central portion” to other inlet and outlet ports. Included in the valve is a rotor, which in operation interconnects various of the inlets and outlets. Attached to the rotor via a post is an elongated aluminum handle, whose manual movement is designed to change the position of the rotor. As described at column 9, lines 60-62 of the Erlich patent: 
     A fulcrum point is provided for the handle, so that when the handle is depressed, the post will axially lift the rotor from its seated position. 
     (Numerals deleted.) The valve of the Erlich patent additionally incorporates both a Teflon bearing and a metallic bearing plate, which purportedly facilitate rotation of the handle while preventing wear of the bearing. In actual use, however, consumers frequently fail to depress the handle before attempting to rotate it, often breaking (or at least prematurely wearing) the handle or the pin by which it is attached to the post. 
     Yet another multi-port valve marketed by Praher under the name “Eco-Valve” includes a plastic handle connected to a rotor. Rotating the handle causes a pair of rollers to travel along a plate, the upper surface of which includes four recesses of semi-circular cross-section for receiving the rollers at various intervals. Additionally incorporated into the upper surface are two opposed indentations in which the rollers may rest. Receiving the rollers in the recesses or indentations apparently helps position the rotor correctly relative to the ports of the valve. As with the device of the Erlich patent, some possibility of breaking the plastic handle exists should the force exerted by the user not translate to the rollers in a manner sufficient to permit them to be unseated from their respective recesses. 
     SUMMARY OF THE INVENTION 
     The valve assembly of the present invention provides an alternative structure to these existing multi-port valves. Unlike the Eco-Valve and that of the Erlich patent, the present valve assembly includes no elongated handle possibly subject to premature breakage. Instead, the structure utilizes a knob—which the user need not lift—coupled to a post in which an elongated slot is formed. 
     Through the slot of the post is passed a cylindrical or other appropriately-shaped shaft terminating in a pair of opposed followers, sometimes denominated “rollers,” with generally-circular cross-section. The rollers interact with a stationary “cam” having one or more (preferably but not necessarily six) recesses and (preferably but not necessarily two) indentations into which the rollers may be received or rest. Unlike the plate of Praher&#39;s Eco-Valve, the cam of the present invention incorporates non-semicircular, asymmetrically-shaped recesses, both to help restrict movement of the knob to one direction (typically counterclockwise) and to facilitate unseating of the rollers when their movement is desired. The elongated slot, whose mouths are longer than the diameter of the shaft, additionally permits the rotor to lift before it turns, momentarily destressing an internal sealing mechanism to reduce or avoid its premature wear. 
     Embodiments of the valve assembly may include a two-piece housing, with the upper portion generally spherically shaped (albeit truncated) and the lower portion shaped generally as a truncated toroid. In such cases the housing may be divided along or adjacent the plane in which the sealing mechanism resides, with the upper portion having a port for connecting to a pump and the lower portion having multiple inlets and outlets. This design for the housing assists in minimizing the surface area required for the assembly for particular fluid flow rates and volumes, while also matching generally the shape of the surfaces of pressure tanks to which it typically mounts. 
     Additionally incorporated into certain valve assemblies of the present invention is an “accelerator” gear whose teeth substantially complement those formed in the bottom of the post. The angled edges of the teeth facilitate, and thus effectively “accelerate,” proper seating of the post and thereby of the rotor as well. Including vertical sides in the teeth, by contrast, avoids interference with proper lifting of the rotor when the knob is turned. 
     It is therefore an object of the present invention to provide a valve assembly adapted for use especially, although not necessarily exclusively, in connection with swimming pools. 
     It is another object of the present invention to provide a multi-port valve assembly lacking an elongated handle, thereby avoiding breakage problems sometimes associated with such handles. 
     It is an additional object of the present invention to provide a valve assembly having a post to which a knob attaches, the post defining an elongated slot through which a shaft may pass. 
     It is a further object of the present invention to provide a valve assembly which utilizes a cam having asymmetrical recesses for receiving followers connected to the shaft. 
     It is yet another object of the present invention to provide a valve assembly in which a rotor connected to the post lifts before it turns, momentarily destressing an internal sealing mechanism to reduce or avoid premature seal wear. 
     It is also an object of the present invention to provide a valve assembly including a gear whose teeth not only substantially complement those formed in the bottom of the post, but also are shaped to facilitate proper seating of the post and rotor as well. 
     Other objects, features, and advantages of the present invention will become apparent with reference to the remainder of the text and drawings of this application. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective view of a valve assembly of the present invention. 
     FIG. 2 is a cross-sectional view of the valve assembly of FIG.  1 . 
     FIG. 3 is a top plan view of the lower housing of the valve assembly of FIG.  1 . 
     FIG. 4 is a perspective view of the lower housing of FIG.  3 . 
     FIG. 5 is a bottom plan view of the upper housing, rotor, and post of the valve assembly of FIG.  1 . 
     FIGS. 6A-B are perspective views of the rotor and post of FIG.  5 . 
     FIGS. 7A-B are, respectively, elevational and cross-sectional views of portions of the post of the valve assembly of FIG.  1 . 
     FIGS. 8A-B are, respectively, side and perspective views of the “cam” of the valve assembly of FIG.  1 . 
     FIGS. 9A-B are, respectively, elevational and perspective views of the “accelerator” gear of the present invention. 
     FIG. 9C is an elevational view of a portion of the accelerator gear of FIGS. 9A-B shown engaging teeth of the post of the valve assembly. 
    
    
     DETAILED DESCRIPTION 
     FIGS. 1 and 2 illustrate an embodiment of assembly  10  of the present invention. As detailed therein, assembly  10  may include upper housing  14  and lower housing  18  which in use are connected in suitable manner. FIGS. 1-2 show one such connection means, in which external threads  22  of lower housing  18  engage internal threads  26  of upper housing  14 . Housings  14  and  18  additionally or alternatively may include respective flanges  30  and  34  through which a fastener such as a pin or screw  38  may pass. 
     Portions of upper housing  14  resemble a dome or sphere. Included in upper surface  42  of the dome-like housing  14  is an opening  46  through which post  50  protrudes. Also incorporated into housing  14  is inlet  54 , which in use typically connects via a hose to a pump or similar equipment. Housing  14  is otherwise generally hollow, defining an area  58  in which water or other fluid may be received. Although not shown in the figures, housing  14  additionally may include an aperture into which a pressure gauge or sensor is mounted. 
     FIGS. 1-4 illustrate lower housing  18 . Embodiments of assembly  10  often define four ports  62 A-D, although fewer or greater numbers of ports may be included in housing  18  when necessary or desired. These embodiments additionally contain walls  66 A-E, central wall  67 , and interior peripheral wall  68 , which collectively divide area  70  within housing  18  into five segments  74 A-E (one more than the number of ports  62  provided). Each segment  74  is adapted to receive fluid communicated from either inlet  54  or another segment  74  (or both), with its boundary walls  66  and  68  helping to confine the fluid to that particular segment  74 . 
     As examples, together with central wall  67  and peripheral wall  68 , walls  66 A and  66 B define segment  74 A, which communicates with port  62 A, while walls  66 D and  66 E define segment  74 D in communication with port  62 D. In typical swimming pool applications port  62 A provides an outlet for waste water, port  62 B connects to the outlet of a filter, port  62 C provides a direct outlet to the pool, and port  62 D connects to the inlet of the filter. Segment  74 E, by contrast, although capable of receiving fluid from inlet  54 , does not communicate with any of ports  62 A-D. It thus corresponds to the “closed” position of valve assembly  10 . 
     Positioned principally within upper housing  14  is rotor  78 , which in use rotates to permit (or forbid) fluid to communicate either from upper housing  14  to particular segments  74  of lower housing  18  or from one segment  74  to another within lower housing  18 . In the embodiment of rotor  78  shown in FIGS. 5-6, lower surface  82  of the rotor  78  has four areas  86 A-D, two of which ( 86 A and  86 B) are essentially flat and designed to fit flush against pairs of adjacent walls  66  to prevent fluid from communicating with the segments defined by those walls  66 . Area  86 C is an opening, which permits fluid to communicate from upper housing  14  to lower housing  18 . Area  86 D defines a cavity which, although preventing fluid from communicating between housings  14  and  18 , is adapted to allow fluid to communicate between adjacent segments  74  with which it is aligned. 
     Also illustrated in FIGS. 1-2 and  5  is o-ring  90 , which seals the region of assembly  10  adjacent threads  22  and  26  to prevent undesired fluid leakage in that region. Similarly shown is gasket  94 , which constitutes a sealing mechanism intended to prevent unwanted fluid exchange between upper housing  14  and lower housing  18 . The “spoked” gasket  94  is adapted to abut walls  66 A-E, central wall  67 , and peripheral wall  68  and in some embodiments of assembly  10  is fitted into rotor  78  for enhanced performance. This fitting additionally facilitates replacement of rotor  78  and gasket  94  as a unit when desirable to do so. 
     Integrally formed with or otherwise attached to rotor  78  is post  50 . Usually (but not necessarily) cylindrical throughout much of its length, post  50  transfers motion of knob  98  to rotor  78 . In some embodiments of assembly  10 , post  50  may include one or more circumferential grooves  102  into which o-rings  106  may be fitted for additional protection from leakage. Circumscribing portions of post  50  are spring  110  and plates  114 A and  114 B, which collectively bias gasket  94  against walls  66 A-E, central wall  67 , and peripheral wall  68 . 
     Protruding through opening  46  as noted earlier, post  50  may include at its top  118  a brass or other threaded insert  122  into which fastener  126  may be fitted. Fastener  126  additionally passes through knob  98 , thus securing knob  98  to post  50  for rotational motion. When appropriate, washer  130  may be interposed between fastener  126  and knob  98 . 
     Detailed in FIGS. 6-7 is slot  134  formed in post  50 . Slot  134  is generally shaped complementary to an opposed pair of elongated frustums. Stated differently, slot  134  is designed to be widest at its opposed mouths  138  and narrowest at its center  140 , thereby permitting some rotation (in, e.g., direction A) of shaft  142  (shown in phantom lines in FIG. 5B) before the shaft  142  contacts surfaces  146  and  150  of slot  134 . Hence, each mouth  138  typically is substantially longer than the diameter of shaft  142 , although its height is approximately the same as (albeit slightly larger than) the diameter of the shaft  142 . 
     Interposed between knob  98  and housing  14  and circumscribing post  50  is cam  154  (see FIGS.  8 A-B). Included in the upper portion  156  of cam  154  are recesses  158  and indentations  162 , of which there are preferably six and two, respectively. Fewer or greater numbers of these recesses  158  and indentations  162  may be included, however, and upper portion  156  may furthermore contain an integrally-formed guide rail  166  if desired to prevent followers (or rollers)  170 A-B from sliding off upper portion  156  toward post  50 . 
     Recesses  158  receive the followers  170 A-B, which are attached adjacent respective ends  174 A-B of shaft  142 . Each reception of followers  170 A-B by recesses  158  defines a distinct operational position of assembly  10 , selectively positioning rotor  78  vis-a-vis segments  74  and sealing gasket  94  against walls  66 A-E, central wall  67 , and peripheral wall  68 . By contrast, when followers  170 A-B are not received by recesses  158  (but rather are travelling along surface  178  of upper portion  156  or resting in indentations  162 ), rotor  78  effectively is “lifted” relative to lower housing  18  so that gasket  94  no longer abuts walls  66 A-E, central wall  67 , and peripheral wall  68 . This “lifting” action destresses gasket  94 , avoiding its frictional contact with walls  66 A-E,  67 , and  68  when knob  98  is turned. Placing followers  170 A-B in indentations  162  represents the “storage” or “winter” position of assembly  10 , as it reduces deterioration of gasket  94  that might otherwise be caused by longstanding contact with walls  66 A-E,  67 , and  68 . 
     Phantom line  182  illustrates the boundary of a recess  158  were it semi-circularly shaped. As shown especially in FIG. 6, however, recesses  158  are asymmetrically shaped, having a decreased slope on the leading surface  186  encountered by a follower  170  moving in direction B. Because trailing surface  190  substantially complements the shape of a follower  170 , knob  98  cannot as readily be turned in the direction opposite direction B. Accordingly, cam  154  effectively restricts movement of knob  98  to unidirectional (typically counterclockwise) motion. 
     With followers  170 A-B positioned in a particular pair of recesses  158 , a consumer may utilize assembly  10  merely by turning knob  98 . Because ends  174 A-B of shaft  142  are fitted within respective internal recesses  192 A-B of knob  98 , turning the knob  98  causes shaft  142  to begin rotating, forcing followers  170 A-B to commence climbing the leading surfaces  186  of the particular recesses  158 . Continued rotation of shaft  142  eventually causes it to contact surfaces  146  and  150  of slot  134 , after which post  50  turns in tandem with the shaft  142 . The initial climbing action functions to lift rotor  78 , however, thereby destressing gasket  94  to reduce its wear (as noted above) before post  50  and rotor  78  begin to rotate. 
     FIGS. 9A-C, finally, illustrate teeth  194  of “accelerator” gear  198 , which in use engage teeth  202  of the bottom  206  of post  50 . Respective sloped edges  210  and  214  of teeth  194  and  202  facilitate proper seating of rotor  78  and gasket  94  as followers  170 A-B begin to enter recesses  158 . After followers  170 A-B are fully received by recesses  158 , the vertical side walls  218  and  222  of abutting teeth  194  and  202  prevent unintended changes in position of rotor  78 . As shown in FIG. 9B, gear  198  may include an integral sleeve  226  which, if present, is designed to fit over protrusion  230  of lower housing  18  and be secured in place by a fastener such as screw  234 . 
     The foregoing is provided for purposes of illustrating, explaining, and describing embodiments of the present invention. Modifications and adaptations to these embodiments will be apparent to those skilled in the art and may be made without departing from the scope or spirit of the invention.