Patent Publication Number: US-2017370077-A1

Title: Temperature-limiting valve assembly with high temperature sanitary flushing mode

Description:
FIELD OF THE INVENTION 
     This invention generally relates to valves and more particularly to temperature limiting valves. 
     BACKGROUND OF THE INVENTION 
     Temperature-limiting valves are used to prevent a user from being scalded by high temperature water resulting from the temperature control, typically the associated handle, on a valve being turned too far toward the maximum hot position. They are necessary because typically hot water supplies are far hotter than even the hottest temperature that a user will be using in a sink faucet application or in a shower application. Such thermostatic temperature-limiting valves typically have a temperature-responsive element that limits the flow of hot water in order to maintain the outlet water temperature at or below a predetermined temperature. 
     Some temperature-limiting valve may also have a mechanical adjustment mechanism that can be used to adjust the maximum temperature of water supplied by the valve, typically by adjusting the limiting position of the temperature control which as stated above may be a handle. An example of such a valve is shown in U.S. Pat. No. 7,163,157 the teachings and disclosure of which are incorporated by reference herein. 
     In certain settings, it may be necessary to disable the temperature limiting functionality of such valves. As one example of many, a health care facility must periodically sanitize their water lines. This can be done by directing very high temperature water through the lines. However, to achieve this operation, the temperature limiting functionality of the valves at the outputs of the lines, e.g. showers, sinks, etc., must be disabled. While such an operation has proven an effective mechanism for sanitization, it is not without drawbacks. 
     As one drawback, existing temperature limiting valves are relatively complex in their construction. As a result, to disable the temperature limiting functionality, especially on those valves which include the above mentioned mechanical adjustment mechanism can be quite complex. Typically, a significant portion of the valve must be disassembled to disable its temperature limiting functionality, i.e. to place the valve into a sanitation flush mode. The valve must then be temporarily reassembled to allow the operator to adjust the valve setting so that very hot water is directed through the valve and water lines associated therewith. After the sanitization operation is complete, another disassembly and subsequent reassembly are required to place the valve back in its normal operating configuration. 
     As another drawback, there is a risk that an operator conducting the sanitization operation may forget to replace the temperature limiting componentry of the valve. As a result, a subsequent user may be scalded by the very hot water allowed to flow through the system. 
     Accordingly, there is a need in the art for a temperature limiting valve with a high temperature sanitation flush mode which may be easily transitioned for sanitation operations. The invention provides such a valve and associated componentry. These and other advantages of the invention, as well as additional inventive features, will be apparent from the description of the invention provided herein. 
     BRIEF SUMMARY OF THE INVENTION 
     In one aspect, the invention provides a temperature limiting valve assembly that can be rapidly transitioned into a sanitation flush mode in an efficient manner without significant disassembly of the temperature limiting valve assembly. An embodiment according to this aspect includes a valve body. The valve body has a housing which defines at least one inlet and at least one outlet. A valve member is arranged within the housing and operable to control a flow along a flow path between the at least one inlet and the at least one outlet. The valve body also includes a valve stem. The valve stem is mechanically coupled to the valve member to position the valve member in a desired position relative to the flow path. The valve stem defines a first abutment surface. This embodiment of the temperature limiting valve assembly also includes a limiting arrangement. The limiting arrangement includes a limiting member which surrounds the valve stem. The valve stem is linearly and rotationally moveable within a cavity defined by the limiting member. The limiting arrangement also includes a clip removably mounted relative to the limiting member. The clip defines a second abutment surface. The second abutment surface is arranged for abutment with the first abutment surface of the valve stem at a limit position to prevent continued linear movement in a first direction of said valve stem within the cavity of the limiting member. 
     The at least one inlet may include a hot water inlet and a cold water inlet. Hot water from the hot water inlet and cold water from the cold water inlet are mixed within the valve body to produce an outlet flow at the at least one outlet. A temperature of the outlet flow is determined by the position of the valve stem relative to the housing. The limit position defines a maximum temperature of the output flow. 
     The valve stem has a first diameter and a second diameter which is less than the first diameter. The first abutment surface is defined at a transition from the first diameter to the second diameter. The clip includes a valve stem receiving portion. The valve stem receiving portion defines a third diameter which is less than the first diameter and greater than the second diameter. The clip is resiliently deformable to an expanded position. In the expanded position, the valve stem receiving portion defines a fourth diameter which is at least as large as the first diameter. 
     The limiting member has a generally cylindrical outer periphery and includes a pair of opposed slots formed in said generally cylindrical outer periphery. The clip has an open side such that it has a pair of opposed leg portions. The pair of opposed leg portions are received, respectively, in the pair of opposed slots of the limiting member. The clip includes a valve stem receiving portion. The valve stem receiving portion is disposed between the pair of opposed leg portions. The pair of opposed leg portions are resiliently deformable toward and away from one another to vary a size of the valve stem receiving portion. 
     In another aspect, the invention provides a temperature limiting valve assembly which reduces the risk that the temperature limiting functionality of the valve will not be re-enabled after a sanitation flushing operation. An embodiment according to this aspect includes a valve body. The valve body has a housing defining at least one inlet and at least one outlet. A valve member is arranged within the housing and arranged to control a flow along a flow path between the at least one inlet and the at least one outlet. The valve body also includes a valve stem. The valve stem is mechanically coupled to the valve member to position the valve member in a desired position relative to the flow path. The valve stem defines a first abutment surface. 
     This embodiment also includes a limiting arrangement. The limiting arrangement includes a limiting member surrounding the valve stem. The valve stem is linearly and rotationally moveable within a cavity defined by the limiting member. The limiting arrangement also includes a clip. The clip defines a second abutment surface. The clip is resiliently deformable to prevent movement of the first abutment surface past the second abutment surface in a first direction, and permit movement of the first abutment surface past the second abutment surface in a second direction opposite the first direction. 
     The clip is resiliently deformable to an expanded position. In the expanded position, a diameter of a valve stem receiving portion of the clip increases. The valve stem has a first diameter and a second diameter. The first abutment surface is formed at a transition from the first diameter to the second diameter. When the clip is not in the expanded position, a portion of the valve stem defining the second diameter passes through the clip. The clip may be removably mounted relative to the limiting member in this embodiment. 
     In yet another aspect, the invention provides a temperature limiter which may be installed on an existing valve to allow for rapid transitioning of the valve into a sanitation flush mode, and also reduce the risk that the temperature limiting functionality of the valve will not be re-enabled after the sanitation flushing is complete. An embodiment according to this aspect includes a limiting member. The limiting member defines an internal cavity. The internal cavity is configured for receipt of a valve stem of the valve. The temperature limiter also includes a clip removably mounted relative to the limiting member. The clip has an installed position and an uninstalled position. In the installed position, an abutment surface of the clip is positioned within the internal cavity and is arranged to permit linear movement of the valve stem in a first direction past a limit position. In the uninstalled position, the abutment surface is not positioned within the internal cavity. 
     The limiting member has a generally cylindrical outer periphery and includes a pair of opposed slots formed in said generally cylindrical outer periphery. The clip has an open side such that it has a pair of opposed leg portions. The pair of opposed leg portions are received, respectively, in the pair of opposed slots. 
     Other aspects, objectives and advantages of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention and, together with the description, serve to explain the principles of the invention. In the drawings: 
         FIG. 1  is a perspective view of an exemplary embodiment of a valve assembly according to the teachings of the present invention; 
         FIG. 2  is a perspective exploded view of the valve assembly of  FIG. 1 ; 
         FIG. 3  is a perspective view of a portion of the valve assembly of  FIG. 1 ; and 
         FIGS. 4-6  are perspective cross sections of the valve assembly of  FIG. 1 . 
     
    
    
     While the invention will be described in connection with certain preferred embodiments, there is no intent to limit it to those embodiments. On the contrary, the intent is to cover all alternatives, modifications and equivalents as included within the spirit and scope of the invention as defined by the appended claims. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Turning now to the drawings,  FIGS. 1-6  illustrate an exemplary embodiment of a temperature limiting valve assembly  8  according to the teachings of the present invention. As will be understood from the following, the temperature limiting valve assembly  8  advantageously overcomes existing problems in the art by allowing for rapid transitioning of the valve assembly  8  from its normal operational mode to a sanitation flush mode. Additionally, the valve assembly  8 , and more particularly a limiting arrangement thereof, reduces the risk that an operator will forget to re-enable the temperature limiting functionality of the valve assembly  8  once the sanitation flushing operation is complete. 
     With particular reference to  FIG. 1 , valve assembly  8  is illustrated schematically installed in an exemplary operational environment. Indeed, valve assembly  8  is connected to a hot water supply  12  and a cold water supply  14 . Water from these supplies is mixed within valve assembly  8  to produce an output flow which is directed to outlets  16 ,  18 . As an example, outlet  16  may be a shower head, while outlet  18  may be a bath tub spout. It will be readily recognized that while two outlets  16 ,  18  are shown, valve assembly  8  need only contain at least one outlet. 
     As will be discussed more fully below, valve assembly  8  includes a valve body  10  (see  FIG. 2 ) and limiting arrangement (also referred to herein as a temperature limiter) installed on valve body  10  which defines a limit position of valve assembly  8 . This limit position in turn defines a maximum temperature of an outlet flow of valve assembly  8 . Indeed, valve assembly includes a handle as shown. As this handle is rotated counter clockwise relative to  FIG. 1 , the temperature of the outlet flow increases. When enabled, the limiting arrangement allows for a maximum rotation of an angle of θ 1  of the handle. The limiting arrangement thus prevents increasing the temperature of the outlet flow beyond this limit position. When not enabled, the limiting arrangement does not restrict rotation of the handle, and thus the same may be rotated to a greater angle, e.g. θ 2 , which allows for an increase in the temperature of the outlet flow to a temperature satisfactory for sanitation flushing of the exemplary operational environment. 
     It will be readily recognized from the following, that the particular embodiment of the valve body  10  illustrated is non-limiting on the invention. Indeed, the limiting arrangement described below may be installed on any valve which utilizes a helical style valve stem actuation, i.e. a valve stem which rotates and moves linearly to achieve the mixing function described above. 
     Turning now to  FIG. 2 , valve body  10  and the aforementioned limiting arrangement will be described in greater detail.  FIG. 2  illustrates an exploded view of the valve body  10  as well as an exploded view of the aforementioned limiting arrangement relative to valve body  10 . Valve body  10  includes a valve housing  20 . Valve housing  20  includes a hot water inlet which connects to hot water supply  12  (see  FIG. 1 ), as well as a cold water inlet  24  which connects to the cold water supply  14  (see  FIG. 1 ). Additionally, valve housing  20  includes outlet ports  26 ,  28  which respectively connect to outlets  16 ,  18  (see  FIG. 1 ). Valve housing  20  also includes an internal cavity  30 . A flow path extends from each of the aforementioned inlets  22 ,  24  to the outlets  26 ,  28  via cavity  30 . Although not required, inlets  22 ,  24  can also include adjustment screws which extend parallel to valve axis  32 . Each adjustment screw may be utilized to close off its respective inlet  22 ,  24 . This is advantageous for the sanitation flush mode of valve assembly  8  as it allows a user to fully close off the flow of cold water to maximize the outlet temperature of valve assembly  8 . These adjustment screws may be accessed via a port in a trim plate (not shown) or by removal of the trim plate. 
     Cavity  30  defines a valve access  32  about which a valve member  34  (also referred to by those of skill in the art as a cartridge) and a valve stem  36  mechanically coupled to valve member  34  are rotatable about. Valve member  34  is schematically shown as any number of valve member arrangements may be utilized to control the flow along the above-introduced flow path. Valve stem  36  is a shaft-like component. It has a first portion at a first diameter D 1  and a second portion at a second diameter D 2 . An end portion extends away from the second portion to provide a mounting location for a handle  40  of valve body  10 . As is generally understood in the art, and applied to work at the handle  40  is transferred valve stem  36  and in turn to valve member  34 . 
     A valve cap  38  seals valve member  34  within cavity  30 . Shaft  36  extends through a bore  44  formed in valve cap  38  to allow for connection of handle  40 . Additionally, a cosmetic covering  42  may also be included to shroud or otherwise cover portions of valve body  10 , including valve cap  38  and the connection interface between handle  40  and valve stem  36 . 
     Turning now to the limiting arrangement of valve assembly  8 , as introduced above, the same is installed on valve body  10 . Limiting arrangement  48  includes a clip  50  which is removably mounted relative to a limiting member  52 . As will be understood from the following, clip  50  is physically attached to valve stem  36  and can be selectively removed therefrom, thereby making it removably mounted relative to the limiting member  52 . It is also envisioned that clip  50  may be removably mounted relative to limiting member  52  via a direct engagement between clip  50  and limiting member  52 . In such an embodiment, limiting member  52  may include tabs or other structures which opposed leg portions  56 ,  58  interlock with to hold it in place on limiting member  52 . 
     Indeed, clip  50  includes an opening  54  and a pair of opposed leg portions  56 ,  58 . Leg portions  56 ,  58  are resiliently deformable toward and away from one another to decrease and increase a diameter D 3  defined by a shaft receiving portion  70  of clip  50 . As will be understood from the following, this resilient deformability of clip  50  allows clip  50  to accommodate diameter D 2  as well as diameter D 1  of valve stem  36 . It will be understood, however, that the shaft receiving portion  70  may need not define a diameter, i.e. take on a fully or partially circular shape. Indeed, the size and shape of shaft receiving portion  70  need only be such that it has a maximum dimension which is between the values of diameters D 1  and D 2 . Indeed, a rectangular cut out could be employed for shaft receiving portion  70  as one of many examples. Clip  50  may be formed in any manner to achieve its functionality described herein. As non-limiting examples, clip  50  may be a molded component, a stamped metal component, or formed from bent wire. 
     Limiting member  52  has a generally cylindrical outer periphery. A pair of opposed slots  64 ,  66  are formed in this outer periphery. These slots  64 ,  66  communicate with a bore  68  extending through limiting member  52 . Slots  64 ,  66  receive leg portions  56 ,  58  (dictated  56 ,  58 ) of clip  50 . As a result, a portion of each leg portion  56 ,  58  is disposed within in bore  68  of limiting member  52 . Limiting member  52  also includes a threaded end  74  which threadably attaches to a hub  76  formed on valve cap  38 . 
     Turning now to  FIG. 3 , valve body  10  is illustrated with limiting arrangement  48  installed thereon. Handle  40  and cosmetic covering  42  (see  FIG. 2 ) have been removed in this view for purposes of clarity. As introduced above, valve member  34  and valve stem  36  utilize a helical style actuation. As a result, rotation of valve stem  36  about valve access  32  in rotational direction  80  also results in linear movement of valve stem  36  relative to valve body  10  in linear direction  82 . Likewise, rotation of valve stem  36  about valve access  32  in rotational direction  84  also results in a linear movement of valve stem  36  relative to valve body  10  in linear direction  86 . 
     As can be seen in  FIG. 3 , clip  50  is installed on limiting member  52 . The second portion of valve stem  36  at diameter D 2  extends through the bore  48  of limiting member  52 , as well as through the valve stem receiving portion  70  of clip  50  when clip  50  is not in an expanded position as a result of the resilient deformation of leg portions  56 ,  58  (see  FIG. 2 ) away from one another. When not in the expanded position, the diameter D 3  defined by valve stem receiving portion  70  is such that it is smaller than the diameter D 1  of valve stem  36 . Accordingly, continued linear movement in linear direction  82  of valve stem  36  will bring a first abutment surface defined at the transition in between diameter D 1  and diameter D 2  into abutment with a second abutment surface defined by clip  50  as discussed below. Such a configuration prevents further movement of valve stem  36 , and thus also prevents any further increase in the temperature of the outlet flow from valve body  10 . 
     Turning now to  FIGS. 4-6  the same illustrate the various stages of the aforementioned functionality. It will be noted that in these views, valve cap  38  has been removed for purposes of clarity in illustration. With particular reference to  FIG. 4 , as can be seen in this cross-sectional view, clip  50  extends through limiting member  52  as described above. The first abutment surface  102  formed on valve stem  36  is spaced apart from the second abutment surface  92  of clip  50 . As a result, a force may be applied to handle  40  to rotate valve stem  36  about valve axis  32  in rotational direction  80  (see  FIG. 3 ) to increase the temperature of the outlet flow from valve body  10 . Turning now to  FIG. 5 , this rotation may continue until first abutment surface  102  encounters second abutment surface  92  as illustrated in  FIG. 5 . Such an abutment defines the limit position introduced above of valve assembly  10 . Further rotation of valve stem  36  is prevented, and as such, increasing the temperature of the outlet flow of valve body  10  is also prevented. As can be understood from the discussion herein, the configuration shown in  FIGS. 4 and 5  are those germane to the normal operation of valve assembly  8 . In an alternative embodiment, the clip  50  thickness and/or shape may be such that first abutment surface  102  encounters second abutment surface  92  prior to diameter D 1  encountering limiting member  52 , e.g. prior to entering bore  68 . 
     However, when it is desirable to place valve assembly  8  into a sanitation flush mode to allow for increase in the temperature of the outlet flow from valve body  10  beyond that permitted by the aforementioned limiting position, clip  50  must be temporarily removed from limiting member  52 . Once removed, valve stem  36  may continue to rotate about valve axis  32  in rotational direction  80  to an angle of Θ 2  (see  FIG. 1 ) wherein first abutment surface  102  encounters a shoulder at the axial end of limiting member  52 . The aforementioned shoulder, however, is not necessary and may be omitted to permit a greater value for angle Θ 2 . In such an alternative configuration, the diameter of bore  68  (see  FIG. 2 ) would be increased to allow first abutment surface  102  to protrude axially from bore  68  as opposed to being stopped by the aforementioned shoulder. In either case, this advantageously allows for high temperature water to flow through valve assembly  10  and its associated conduit to sanitize these components. 
     Advantageously, clip  50  is resiliently deformable as described above such that leg portions  56 ,  58  (see  FIG. 3 ) may be biased away from one another such that valve stem receiving portion  70  (see  FIG. 3 ) may receive the first portion of valve stem  36  at diameter D 1 . In other words, an operator may remove clip  50  and rotate valve stem  36  via handle  40  to place valve assembly  8  into a sanitation flush mode where very high temperature water flows therethrough. Immediately after this rotation, the operator may replace clip  50  back on to limiting member  52  and around valve stem  36  due to its resilient deformability. When the sanitation flushing operation is complete, the operator simply rotates valve stem  36  in rotational direction  84  (see  FIG. 3 ) to transition valve body  10  into a fully off position as valve stem  36  rotates in rotational direction  84  and moves in linear direction  86 , the first portion of valve stem  36  at diameter D 1  will pass back through valve stem receiving portion  70  of clip  50 . Thereafter, leg portions  56 ,  58  of clip  50  (see  FIG. 2 ) will resiliently move back toward one another to decrease the diameter D 3  of shaft receiving portion  70 . In this position, only the second portion at diameter D 2  of valve stem  36  may be accommodated within valve stem receiving portion  70  of clip  50  in its un-expanded position. In an alternative embodiment, clip  50  may be biased towards its unexpanded position by any type of resilient force, e.g. a clasp, wherein removal of this force cases clip  50  to return to its expanded position. 
     Put differently, when not in its expanded position, valve stem receiving portion  70  of clip  50  will not permit movement of the first abutment surface  102  past the second abutment surface  92  in direction  82  (see  FIG. 3 ). However, when clip  50  is in the expanded position, second abutment surface  102  can move past first abutment surface  92  in linear direction  86  (see  FIG. 3 ). 
     Although limiting arrangement  48  has been described in context of valve body  10  illustrated herein, it is contemplated by the invention herein that limiting arrangement  48  may be provided as a stand-alone sub assembly which may be retrofit on an existing valve assembly or valve body. Indeed, the embodiment of the limiting arrangement described herein may readily work with any valve stem which employs a helical style actuation. Limiting member  52  need only thread onto such an existing valve body. Further, other mechanical means of joining limiting member  52  to such an existing valve body could be employed. For example, limiting member  52  could be joined to an existing valve body  10  such that it surrounds the valve stem thereof as described herein by the use of a snap fit, a friction fit, fasteners, etc. 
     It will be recognized that such a configuration allows an operator to immediately replace clip  50  after removing it to thereby reduce the risk that the operator will forget to replace clip  50  at a later time. This configuration ultimately reduces the risk that a subsequent user will accidentally scald themselves with very high temperature water not intended for normal use. 
     Indeed, in a typical method of use, handle  40  and cosmetic covering  42  are removed from valve assembly  8 . Clip  50  is then removed from limiting member  52 . Handle  40  may then be replaced onto valve stem  36 . The valve stem is then rotated in rotational direction  80  to a position desirable for sanitation. Once rotated, clip  50  may be immediately reinstalled in limiting member  52 . After completion of the sanitation operation, handle  40  may be rotated in rotational direction  84  to place valve assembly  8  in a fully off position. By doing so, clip  50  will be returned to its non-expanded position. Thereafter, cosmetic covering  42  may be replaced and valve assembly  8  will be ready for normal operation and usage. 
     From the description of the typical method of use above, it will be readily recognized that the transitioning of valve assembly  8  into a sanitation flush mode is an efficient operation which does not require significant disassembly of valve assembly  8 , unlike prior designs. Further, the ability to immediately replace clip  50  reduces the risk that an operator will forget to place valve assembly  8  back into normal operating mode. 
     All references, including publications, patent applications, and patents cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein. 
     The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) is to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. 
     Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.