Abstract:
A diverter valve is disclosed for use in a shower mixer valve or the like. It is constructed to reduce the force needed to be applied by the bather to actuate the diversion. There is a diverter stem that is moveable between a non-diverted and diverted position. The diverter stem includes an upstream portion and a reduced cross sectional waist portion downstream of the upstream portion. The reduced portion interacts with the diverted fluid to reduce the force required to move the diverter stem from the non-diverted to the diverted position.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     Not applicable 
     STATEMENT OF FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable 
     BACKGROUND OF THE INVENTION 
     The present invention relates to fluid control valves which can divert flow between/among multiple outlet fittings. More particularly it relates to structures used therewith which reduce the needed diverter activation force. 
     Most bath tub/shower combinations have a tub filler spout positioned about two feet above the tub floor, and a separate showerhead positioned about six feet above the tub floor. A single mixing valve controls the temperature and rate of flow of the water for both. There is often a diverter unit positioned directly on the tub filler spout. All flow from the control valve will normally go to the filler spout (and thus the tub). However, when the diverter is activated essentially all flow will be directed up to the showerhead. 
     While this type of filler mounted diverter assembly serves the basic functional needs, it disrupts the aesthetics of the tub filler somewhat. Further, diverters of this type can accidentally snag nearby items. 
     Hence, there have been attempts to position the diverter as part of a mixing valve positioned on a room wall. See e.g. U.S. Pat. No. 4,095,610. In such assemblies the bather can first adjust the temperature and volume by starting flow through the mixer and sampling the water exiting the tub filler. Once the desired temperature and volume are reached, the tub drain can be closed to fill the tub, or alternatively the diverter unit portion of the mixer can be activated to send the water to the showerhead. 
     However, current diverters used with this type of shower mixer can require a significant amount of force to actuate the diverter. For arthritic or otherwise disabled persons even this can be painful or difficult. 
     U.S. Pat. No. 1,666,531 teaches a diverter that is maintained in the shower diversion setting by water pressure, such that when the water is turned off the diverter automatically returns the water flow path to the tub filler. However, when in the resting tub filler position, the diverter is biased to stay in that position by both an internal spring force and water pressure. Thus, both increasing spring force and water pressure must be overcome to move the diverter from the tub filler position toward the shower outlet position. 
     U.S. Pat. Nos. 3,841,346 and 4,675,924 disclose diverters that are maintained in one position by water pressure. However, the user is required to overcome a significant amount of spring force to manipulate the diverter. 
     In any event, in certain jurisdictions (e.g. those governed by the Americans with Disabilities Act), a series of guidelines and regulations have been (and are likely to be) developed placing upper limits on the amount of force a user of a facility can be required to impart in order to use that facility. Architects and building owners are therefore becoming increasingly reluctant to specify products which present this type of problem. 
     Thus, a need exists for diverters, particularly diverters used with shower mixers of this type, that can be operated with less actuation force. 
     SUMMARY OF THE INVENTION 
     In one aspect the present invention provides a diverter valve. There is a housing having an internal chamber, a supply port in fluid communication with the internal chamber and coupleable to a fluid supply, a first outlet, a second outlet, and a stem moveable within the chamber between a first position at which the stem permits fluid communication between the supply port and the first outlet while inhibiting fluid communication between the supply port and the second outlet, and a second position at which the stem permits fluid communication between the supply port and the second outlet while inhibiting fluid communication between the supply port and the first outlet. 
     The stem includes a downstream portion that has a reduced cross sectional area relative to an upstream portion of the stem. The stem is configured and positioned such that the reduced cross sectional area helps reduce the activation force needed to move the stem from the first position to the second position. 
     In preferred forms the housing also houses a mixing valve suitable to control both temperature and volume, the stem tapers radially inwardly from the upstream portion to the downstream portion, the stem also flares radially outwardly downstream of the downstream portion, and the upstream portion is essentially cylindrical. In other forms the stem is linked to a seal coupled to the upstream portion, there is a biasing member (e.g. a spring) urging the stem towards the first position, and a stop member is provided to help capture the compression spring. 
     In another aspect the invention provides a diverter valve coupleable to a fluid supply to selectively direct a fluid between two outlets. The valve has a cylindrical chamber, a supply port in fluid communication with the chamber and coupleable to the fluid supply, a first outlet, a second outlet, and a generally cylindrical diverter stem moveable within the chamber between a non-diverted position at which the diverter stem inhibits fluid communication between the supply port and the second outlet, and a diverted position at which the diverter stem permits fluid communication between the supply port and the second outlet. 
     The diverter stem has an upstream portion, a downstream portion, and a reduced cross sectional waist between the upstream and downstream portions. The waist tapers radially inwardly from the upstream portion and flares radially outwardly towards the downstream portion. Thus, the diverter stem is configured and positioned such that the reduced cross sectional area helps reduce the activation force needed to move the stem from the first position to the second position. 
     It will be appreciated that these embodiments provide a diverter valve requiring a reduced activation force to move the diverter from the non-diverted to the diverted position. This is achieved at low cost and in a reliable manner. This not only helps comply with governmental regulations, it provides the device with a usage feel that gives the impression of a well constructed device. 
     These and still other advantages of the present invention will be apparent from the detailed description and drawings. What follows is merely a preferred embodiment of the present invention. To assess the full scope of the invention the claims should be looked to. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a left, frontal, upper perspective view of a shower mixer that incorporates a diverter valve of the present invention; 
         FIG. 2  is a left, frontal, upper perspective view of a housing portion thereof, with diverter valve components shown exploded there from; 
         FIG. 3  is a frontal view of the  FIG. 2  assembly, but with the diverter valve not exploded from the rear housing; 
         FIG. 4  is a cross sectional view along line  4 - 4  of  FIG. 3 , showing the diverter valve in a non-diverted (tub filler directed) position; 
         FIG. 5  is a view similar to  FIG. 4 , but showing the diverter valve in an intermediate position as it begins to divert; and 
         FIG. 6  is a view similar to  FIG. 4 , but with the diverter valve shown in the fully diverted position. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  shows a shower mixer generally  8  having a diverter valve  10 , a mixing valve  12 , a handle  16  for rotating the control components of the mixing valve, and a decorative escutcheon  18 . The mixing valve  12  is received in a mixing cavity  26  of the main housing  20 . That housing receives a hot water supply into conduit  22  and a cold water supply into conduit  24 . 
     Water leaving the housing  20  either leaves via outlet  28  (per  FIG. 4 ) or outlet  30  (per  FIG. 6 ). The mixing valve  12  is preferably of a conventional type where rotating the handle  16  controls both temperature and volume (e.g. increasing rotation starts a cold volume, which then increases to a maximum cold volume, which then blends to create a hotter flow). 
     The specific type of mixing valve is not critical. Further, the mixer need not be for use with a tub/shower combination. Instead, it could control flow between a main faucet and a spray head, or between a main faucet and a pot filler. 
     Mixing cavity  26  is in fluid communication with a chamber  32  defined by a recess  34 , and the main housing  36  of the diverter valve is threadably engaged with the recess  34  to install it in place. The water in the mixing cavity  26  flows under line pressure through a supply port  38 . The subsequent path of the water is determined by the position of a diverter stem  40 . 
     As best seen in  FIG. 4 , there is an axial passageway  42  formed in the diverter body  36  which slideably receives the diverter stem  40 . As also can be appreciated from  FIG. 2 , the diverter stem  40  includes an upstream end  44  proximate the supply port  38  (when assembled), and a downstream end  46  that extends beyond the diverter body  36  to link with control knob  48 , which in turn can be secured via set screw  49  threadably engaging a transverse hole  51  in the diverter stem  40  and also part of the knob  48 . 
     Importantly, the diverter stem  40  also has an narrowed portion  50  proximate the upstream end  44 . Thus, a reduced portion  52  of the diverter stem  40  is downstream of the upstream portion  50  and tapers from the upstream portion  50  toward a waist  54 , and then flares from the waist  54  toward a portion  56  located downstream. The taper and the flare of the reduced portion  52  may be gradual or more abrupt, and may take on a variety of forms. 
     It is the main purpose of this structure to help reduce the activation force “F” required to move the diverter stem  40  between the non-diverted and diverted positions. Of course, it should be appreciated that instead of tapering, a similar functional effect may be achieved using stepped narrowing. Also, the narrowing need not be symmetrical around the circumference of the stem. 
     In any event, there is a spring or other biasing member  58  which tends to bias the diverter towards the tub filling position of  FIG. 4 . It is captured between a shoulder  59  of the diverter body  36  and a removable c-clip  61 . 
     In the non-diverted tub filling position (shown in  FIG. 4 ), the supply port  38  of the example embodiment is in fluid communication with the tub fixture port  28 , and the water is prevented from flowing along the diverter stem  40  (to reach showerhead port  30 ). The seal  60  (e.g. an o-ring) is fit into an annular groove  62  formed in a portion  64  of the diverter body. 
     At this time stem seal  67  fits into an annular groove  69  formed proximate an upstream end  71  of the diverter body  36 . It helps seal against the upstream portion  50  of the diverter stem  40  when the diverter stem  40  is in the non-diverted position. 
     There is also another stem seal  73  seated in an annular groove  75  formed in the downstream portion  56  of the diverter stem  40 . The second stem seal  73  engages the axial passageway  42  and prohibits fluid from leaking past the diverter stem  40  via the axial passageway  42 . The seals and components used in the example embodiment are generally configured and designed to operate at typical line pressures. 
     Note also that there is a cap  68  captured at the upstream end  44  of the diverter stem  40  by a fastener  70  (e.g., a bolt). The cap  68  helps define the groove  72  that receives a seal  74  (e.g., an o-ring). The seal  74  generally engages the interior surface  76  of the chamber  32  and establishes a moveable sealing interface that is slidable within the chamber  32  as the diverter stem  40  is moved between the non-diverted position (shown in  FIG. 4 ) and the diverted position (shown in  FIG. 6 ). The member  68  of the preferred example embodiment includes a generally domed upstream surface  78  and a generally disc-shaped downstream surface  80 . 
     The position of this seal  74  is particularly important as when it is positioned as shown in  FIG. 6  water can pass along the stem  40  to reach the outlet  30 . However, when it is positioned as shown in  FIG. 4 , water is blocked from the downstream end of the stem. 
     In operation a bather rotates the control handle  16  to allow hot and cold water to flow into the mixing cavity  26  via the hot port  22  and cold port  24 , respectively. The resulting mixed water then flows from the mixing cavity  26  toward the supply port  38 . With the diverter stem  40  in the most typical, non-diverted position, the water flows through the chamber  32  and into the tub fixture port  28 , ultimately flowing out of the tub filler/fixture (not shown). 
     The bather may then apply an activation force F to the diverter assembly  10  to push the diverter stem  40  toward the diverted position (shown in  FIG. 6 ). The pushing force F must be enough to overcome the spring biasing, the water line pressure, and initial friction. 
     Turning next to  FIG. 5 , the diverter stem  40  is shown in an intermediate position whereat the seal  74  of the member  68  has moved upstream past the right edge  77  of the supply port  38  (as viewed in  FIG. 5 ). In this position, water begins to flow along the stem. 
     However, the reduced section  52  quickly reduces pushing resistance attributable to water pressure. In fact the water establishes an overall pressure gradient adjacent the diverter stem  40  that itself helps urge the diverter stem  40  toward the diverted position. Thus, the activation force F required to be provided by the bather is reduced in two ways. The water not only quickly stops pushing the stem to the right during diversion, it also helps drag it to the left. 
     As the diverter stem  40  moves more and more to the left, an increasing amount of water is directed downstream along the reduced portion  52  toward the shower fixture port  30 . The water flows along the reduced portion  52  and into an outlet port  82  formed in the diverter body  36 . The outlet port  82  is positioned proximate nipple portion  64  and the reduced portion  52  of the diverter stem  40 . As a result, a sufficient amount of water is directed downstream along the diverter stem  40  and toward the shower fixture port  30 . 
     With specific reference to  FIG. 6 , the diverter stem  40  is shown moved into the diverted position where force provided by the water (e.g. the static and dynamic pressure components), as well as friction, maintain the diverter stem  40  in the diverted position without the application of any further external force. 
     If the flow of water through the control valve  14  is reduced below a critical value (e.g. the valve  12  is turned off), spring  58  can then return the diverter stem  40  to the non-diverted position. As a result, the next time the bather operates the tub/shower plumbing fixture, the water will again initially flow through the tub filler port  28 . 
     A preferred example embodiment of the present invention has been described above. It should be appreciated that many modifications and variations to it can be made without departing from the spirit of the invention. 
     For example, the diverter assembly  10  can be used with a valve having three or more outlets, with additional positions being supplied along the diverter to accommodate that. Further, the diverter need not be used with a mixing valve. Rather, a single supply of water or other fluid could be diverted between multiple outlets using the principles of the present invention. 
     Therefore, the invention should not be limited to the preferred example embodiment described. Rather, the claims should be looked to in order to judge the full scope of the invention. 
     INDUSTRIAL APPLICABILITY 
     The invention provides fluid diverters for manipulating the path of fluid through the diverter, particularly allowing for a reduced actuation force.