Abstract:
A filter with a drain valve is provided. The drain valve mounts within an opening of a housing of the filter. The drain valve has a knob mounted to a valve member thereof. At least one locking structure is disposed between the knob and the valve member to mechanically lock the knob to the valve member. Such a configuration reduces the likelihood that the knob will become inadvertently dislodged during operation.

Description:
FIELD OF THE INVENTION 
     This invention generally relates to fuel/water separators and more particularly to drain valves associated therewith. 
     BACKGROUND OF THE INVENTION 
     Fuel/water separation filters are commonly used in contemporary internal combustion engines. As fuel flows through the filter, water and other contaminants are separated from the fuel and collect in a chamber of the filter. Periodically, the water and other contaminants must be drained from the filter. As a result, the above filters often include drain valves to effectuate drainage of the water and other contaminants. One such filter incorporating a drain valve can be found at U.S. Pat. No. 5,144,978 to Brown et al., the entire disclosure of which is incorporated herein by reference. Embodiments of the present invention generally relate to improvements in the design and function of the aforementioned filters. 
     BRIEF SUMMARY OF THE INVENTION 
     In view of the above, embodiments of the present invention provide a filter with a drain valve assembly that overcomes existing problems in the art. More particularly, embodiments of the present invention provide a drain valve assembly that incorporates a mechanical lock between a knob and a valve member thereof. With such a configuration, there is a reduced likelihood that the knob will become dislodged from the valve member in the field. 
     In one claimed aspect, a filter having a drain valve is provided. A filter according to this embodiment includes a filter housing having media therein. The filter housing has a threaded opening with a valve seat surrounding the opening. The filter also has a valve assembly that includes a valve member and a knob. The valve member has a valve head adapted to seal against the valve seat. The valve member also has a valve stem positioned within the threaded opening. The valve stem has at least one tab projecting from an end thereof. The at least one tab of the valve stem engages the knob to fixedly retain the knob on the valve stem. 
     In another claimed aspect, a filter having a drain valve is provided. The filter according to this embodiment includes a housing having a canister with an opening and a valve seat surrounding the opening. The filter also includes a valve assembly carried by the canister. The valve assembly has a rotatable valve member adapted to seal against the valve seat. The rotatable valve member has an outer periphery defining a lip. A knob having an aperture for receipt of a portion of the rotatable valve member is also provided. The aperture has an inner periphery radially spaced apart from the outer periphery of the portion of the rotatable valve member by a clearance gap. A locking structure is disposed between the knob and the rotatable valve member and axially extends across the clearance gap. The locking structure is operable to bias an abutting surface of the knob against the lip such that the knob is fixedly positioned along the rotatable valve member. 
     In yet another claimed aspect, a filter is provided. A filter according to this embodiment includes a filter housing having filter media therein. The filter housing has an opening with a valve seat surrounding the opening. A valve assembly extends through the opening. The valve assembly has an axially movable valve member and a knob. The axially movable valve member is adapted to move toward and away from the valve seat and seal against the valve seat in a closed position. The knob is mounted to the axially movable valve member with a deformed portion of the valve assembly. 
     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 partial perspective view of a filter with a drain valve according to the teachings of the present invention; 
         FIG. 2  is a partial front cross section of the filter of  FIG. 1  with the drain valve in a closed position; 
         FIG. 3  is a partial front cross section of the filter of  FIG. 1  with the drain valve in an open position. 
         FIG. 4  is on an exploded perspective view of a valve stem and a knob of the drain valve of  FIG. 1 ; and 
         FIG. 5  is a partial front cross section of the knob installed on the stem of the drain valve 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, there is illustrated in  FIG. 1  an exemplary embodiment of a filter  10  incorporating a drain valve assembly  12  mounted to a housing  14  of the filter  10  according to the present invention. As will be discussed in greater detail in the following, the drain valve assembly  12  allows for periodic draining of water and other contaminants collected within the housing  14  during filtration. With reference to  FIG. 2 , the housing  14  has a canister portion that carries filter media  16  within a chamber  18  therein. During the filtration process, water and other contaminants will collect in a bottom of the chamber  18  as illustrated. Periodically, the water and other contaminants within the chamber  18  must be drained to ensure the efficient and effective operation of the filter  10 . As will be discussed in greater detail below, a user of the filter  10  can selectively open and close the drain valve assembly  12  by hand to facilitate such drainage. 
     Still referring to  FIG. 2 , the drain valve assembly  12  is positioned within an opening  20  of the housing  14 . The drain valve assembly  12  includes a rotatable valve member  22  with a knob  24  connected thereto by a deformed portion therebetween. The deformed portion may be part of the valve and/or part of the knob, and in one embodiment, is shown taking the form of locking structures or tabs  50 . The knob  24  is configured for hand manipulation, and rotation of the knob  24  will also result in rotation of the rotatable valve member  22 . The valve member  22  has a valve head  26  that moves linearly towards and away from a valve seat  28  that surrounds the opening  20  upon rotation of the knob  24  and valve member  22 . When the valve head  26 , and more particularly a sealing surface  30  thereof, is in contact with the valve seat  28 , the drain valve assembly  12  is in a closed position such that water and other contaminants cannot drain out of the chamber  18 . 
     Turning now to  FIG. 3 , the drain valve assembly  12  is illustrated in the open position. When in the open position, air is permitted to flow from the exterior of the filter  10  through a vent  32  of the valve member  22  and into the chamber  18  of the housing  14 . When this occurs, the water and other contaminants contained within the chamber  18  will flow out of the housing  14  through a drain  34  formed in the valve member  22 . As such, the drain valve assembly  12  generally moves along direction line  42  to facilitate the periodic draining of water and other contaminants contained within the chamber  18  of the housing  14 . 
     Movement along direction line  42  is provided in part by a threaded nut  40  mounted to the housing and in threaded engagement with the valve member  22 . As a user rotates the knob  24 , the valve member  22  will move into and out of engagement with the valve seat  28 . Although illustrated as incorporating a threaded nut  40 , it is recognized that the opening  20  of the housing  14  can be threaded to allow for the linear movement of the valve member  22  relative to the housing  14  without the use of an additional threaded nut  40 . 
     The valve seat  28  is situated within the chamber  18  of the housing  14  and surrounds the opening  20  thereof. In the illustrated embodiment, the valve seat  28  is a compressible gasket. The gasket is held in place by the threaded nut  40 . 
     Turning now to  FIG. 4 , the valve member  22  has a valve stem  44  that extends away from the valve head  26 . The valve stem  44  has threads  36  formed on an outer surface  38  of the valve stem  44 . The threads  36  engage the threaded nut  40  (see  FIGS. 2 and 3 ) to allow for the selective engagement and disengagement of the sealing surface  30  of the valve head  26  with the valve seat  28 . 
     The valve stem  44  also includes a lip  46  for location of the knob  24 . As illustrated in  FIGS. 2 and 3 , when the knob  24  is fully installed on the valve member  22 , the knob  24  is in abutted contact with the lip  46 . The valve stem  44  also has a keyed portion  48  that matches a keyed aperture  60  of the knob  24 . As will be discussed in greater detail below, the keyed portion  48  and knob  24  maintain a keyed relationship when fully assembled such that the knob  24  cannot rotate relative to the valve member  22 . 
     Still referring to  FIG. 4 , one or more locking structures  50  extend away from the keyed portion  48 . The locking structures  50  are located at an outer peripheral edge  52  of the keyed portion  48 . The locking structures  50  may be intermittently situated around the outer peripheral edge  52 , as illustrated, or can be provided by a continuous lid or edge extending from the outer peripheral edge  52  of the keyed portion  48 . 
     Referring now to  FIGS. 4 and 5 , the locking structures  50  are deformable generally in direction  58  such that they engage a relief  54  formed into a top surface  56  of the knob  24 . The locking structures  50  are deformed against the relief  54  of the knob  24  such that the knob  24  is biased against the lip  46  (see  FIG. 3 ) formed on the valve stem  44  of the valve member  22 . As such, the knob  24  is advantageously fixed to the valve member  22  such that the knob  24  is generally prevented from axial displacement along the valve member  22 . 
     Turning back to  FIG. 4 , the locking structures  50  are illustrated as a deformed portion of the valve stem  22  that generally extends across a clearance gap formed between the valve member  22  and the knob  24 . The locking structures  50  can be deformed in a variety of ways including but not limited to, swaging, punching or similar processes. 
     Referring back to  FIGS. 2 and 3 , the locking structures  50  hold the knob  26  in place along the valve member  22  and against the lip  46  thereof. As the knob  24  is rotated by hand, there is reduced likelihood that the knob  24  will become dislodged from the valve member  22 . As such, the filter  10  generally presents a more robust construction with a reduced failure mode in the field. 
     As described herein, the filter  10  incorporates a drain valve assembly  12  that overcomes existing problems in the art by providing a reliable assembly that can be repeatedly opened and closed with a reduced likelihood that the knob  24  will fall off of the valve member  22 . 
     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.