Patent Publication Number: US-10760252-B2

Title: Automatic air release plunger

Description:
BACKGROUND 
     Drains such as those in toilets, sinks, and tubs are typically unclogged by using a plunger comprised of a deformable head mounted on the end of an elongated handle or shaft. Plunger head designs typically include an air chamber or bellows coupled to a seal. During an unclogging operation, a plunger head seal is held over, or inserted into, the mouth of the drain while the plunger handle is reciprocated in an upward and downward motion that alternately contracts and enlarges the space within the head air chamber. This reciprocating motion then creates an alternating pressure and suction force in the drain passage that is often sufficient to dislodge an obstruction in the drain. 
     SUMMARY 
     One exemplary automatic air release (AAR) plunger implementation for unclogging an obstructed drain in a plumbing fixture having undrained wastewater described herein includes a handle and a hollow, compressible plunger head. The plunger head is open at both a proximal and distal end, and is coupled to the handle at the proximal end of the plunger head. The plunger head also includes a seal extending from its distal end. This seal is capable of sealing the plunger head to a drain opening of the plumbing fixture. In addition, the handle and plunger head include automatic air release features that allow air to flow along an air-escape path from inside of the hollow plunger head into a void formed in the interior of the handle, and thereafter into a channel which extends from the proximal end of the plunger head to a gap that is open to the exterior of the AAR plunger at a proximal end of the handle whenever the plunger head is compressed. The air ultimately escapes out the gap. 
     In another exemplary AAR plunger implementation having multiple air escape paths, the automatic air release features allow air to flow from inside of the hollow plunger head into multiple voids formed in the interior of the handle, and thereafter into multiple channels which extend from the proximal end of the plunger head to a gap that is open to the exterior of the AAR plunger at a proximal end of the handle whenever the plunger head is compressed. The air ultimately escapes out the gap in this implementation as well. 
     Yet another exemplary AAR plunger implementation described herein also includes a handle and a hollow, compressible plunger head. As with other implementations, the plunger head is open at both a proximal and distal end, and is coupled to the handle at the proximal end of the plunger head. The plunger head also includes a seal extending from its distal end. This seal is capable of sealing the plunger head to a drain opening of the plumbing fixture. The handle and plunger head include automatic air release features that allow air to flow along an air-escape path from the inside of the hollow plunger head into a void formed in the interior of the handle and thereafter into one or more channels which extend from the proximal end of the plunger head to a gap that is open to the exterior of the plunger at a proximal end of the handle whenever the plunger head is compressed. However, in this implementation, the automatic air release features include a single hollow ring-shaped projection that wraps around the circumference of the handle and forms the void, a shoulder located at a proximal-most end of the plunger head stub, and a tab. The tab interferes with the shoulder of the plunger head and the proximal end of the handle so as to create the aforementioned gap therebetween. 
     Still another exemplary AAR plunger implementation described herein includes a handle and a hollow, compressible plunger head. As with other implementations, the plunger head is open at both a proximal and distal end, and is coupled to the handle at the proximal end of the plunger head. The plunger head also includes a seal extending from its distal end. This seal is capable of sealing the plunger head to a drain opening of the plumbing fixture. The handle and plunger head include automatic air release features that allow air to flow along an air-escape path from the inside of the hollow plunger head into a void formed in the interior of the handle and thereafter into one or more channels which extend from the proximal end of the plunger head to a gap that is open to the exterior of the plunger at a proximal end of the handle whenever the plunger head is compressed. However, in this implementation, the automatic air release features include an annular indentation that wraps around the circumference of the plunger head stub, and a shoulder located at a proximal-most end of the plunger head stub, and a tab. The tab interferes with the shoulder of the plunger head and the proximal end of the handle so as to create the aforementioned gap therebetween. 
     It should be noted that the foregoing Summary is provided to introduce a selection of concepts, in a simplified form, that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. Its sole purpose is to present some concepts of the claimed subject matter in a simplified form as a prelude to the more-detailed description that is presented below. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The specific features, aspects, and advantages of the AAR plunger implementations described herein will become better understood with regard to the following description, appended claims, and accompanying drawings where: 
         FIG. 1  is a schematic side elevation of an AAR plunger according to the present invention shown in a standing resting condition. 
         FIG. 2  is a schematic side elevation, partly broken away, with the AAR plunger of  FIG. 1  shown in a standing resting condition. 
         FIG. 3  is an enlarged, fragmentary, schematic side elevation, partly in cross-section, showing the AAR plunger of  FIG. 1  with automatic air release features integrated into the handle and plunger head, as well as the air-escape path. 
         FIG. 4  is an enlarged, fragmentary, schematic perspective view, showing the plunger head of the AAR plunger of  FIG. 1  with a plunger head stub slot. 
         FIG. 5  is an enlarged, cross-sectional view of an AAR plunger cut through the section coupling the plunger head to the handle and showing two handle voids and corresponding plunger head stub slots in a rotational position where they do not yet line up. 
         FIG. 6  is an enlarged, cross-sectional view of an AAR plunger cut through the section coupling the plunger head to the handle and showing three handle voids and corresponding plunger head stub slots in a rotational position where they do not yet line up. 
         FIG. 7  is an enlarged, cross-sectional view of an AAR plunger cut through the section coupling the plunger head to the handle and showing a single void and corresponding plunger head stub slot where the slot is wider than the void so as to ensure they line up even if some rotational misalignment exists. 
         FIG. 8  is an enlarged, cross-sectional view of an AAR plunger cut through the section coupling the plunger head to the handle and showing a single void and corresponding plunger head stub slot where the void is wider than the slot so as to ensure they line up even if some rotational misalignment exists. 
         FIG. 9  is an enlarged, cross-sectional view of an AAR plunger cut through the section coupling the plunger head to the handle and showing a single void and corresponding plunger head stub slot where both the slot and the void are wide so as to ensure they line up even if some rotational misalignment exists. 
         FIG. 10  is an enlarged, fragmentary, schematic side elevation, of the plunger head of an AAR plunger showing a shoulder tab. 
         FIG. 11  is an enlarged, fragmentary, schematic side elevation, of an AAR plunger showing the proximal end of the handle in contact with a shoulder tab thereby creating a gap between the proximal end of the handle and the plunger head shoulder. 
         FIG. 12  is an enlarged, fragmentary, schematic side elevation, partly in cross-section, showing a AAR plunger with the proximal end of the handle in contact with a tab thereby creating a gap between the proximal end of the handle and the plunger head shoulder, as well as a ring-shaped void and the air-escape path. 
         FIG. 13  is an enlarged, fragmentary, schematic side elevation, partly in cross-section, showing a AAR plunger with the proximal end of the handle in contact with a tab thereby creating a gap between the proximal end of the handle and the plunger head shoulder, as well as an annular indentation close to the distal end of the plunger head stub and the air-escape path. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description of automatic air release (AAR) plunger implementations reference is made to the accompanying drawings which form a part hereof, and in which are shown, by way of illustration, specific implementations in which the AAR plunger can be practiced. It is understood that other implementations can be utilized and structural changes can be made without departing from the scope of the AAR plunger implementations. 
     It is also noted that for the sake of clarity specific terminology will be resorted to in describing the AAR plunger implementations described herein and it is not intended for these implementations to be limited to the specific terms so chosen. Furthermore, it is to be understood that each specific term includes all its technical equivalents that operate in a broadly similar manner to achieve a similar purpose. Reference herein to “one implementation”, or “another implementation”, or an “exemplary implementation”, or an “alternate implementation”, or “one version”, or “another version”, or an “exemplary version”, or an “alternate version”, or “one variant”, or “another variant”, or an “exemplary variant”, or an “alternate variant” means that a particular feature, a particular structure, or particular characteristics described in connection with the implementation/version/variant can be included in at least one implementation. The appearances of the phrases “in one implementation”, “in another implementation”, “in an exemplary implementation”, “in an alternate implementation”, “in one version”, “in another version”, “in an exemplary version”, “in an alternate version”, “in one variant”, “in another variant”, “in an exemplary variant”, and “in an alternate variant” in various places in the specification are not necessarily all referring to the same implementation/version/variant, nor are separate or alternative implementations/versions/variants mutually exclusive of other implementations/versions/variants. 
     Furthermore, to the extent that the terms “includes,” “including,” “has,” “contains,” variants thereof, and other similar words are used in either this detailed description or the claims, these terms are intended to be inclusive, in a manner similar to the term “comprising”, as an open transition word without precluding any additional or other elements. 
     1 Overview 
     Automatic air release (AAR) plunger implementations described herein are employed when the drain of a plumbing fixture (such as toilet, sink, bathtub, and so on) is clogged by an obstruction and an amount of undrained wastewater remains in the fixture. In general, an AAR plunger includes an elongated handle attached to an upper end of a compressible plunger head. In one implementation, the plunger head is a pleated bellows which is generally conical and can vary in diameter from top to bottom. The plunger head also includes a seal which is attached to its lower end. In one implementation, the seal is designed to either seat securely within a typical drain opening, or alternately, in the case where the drain opening is smaller in diameter than the seal, to form a pressure seal around the smaller drain opening. This seal forms either or both a mechanical and pressure seal with the drain hole being cleared by the plunger, depending upon the diameter of the drain opening. Alternate seal designs and shapes are used in various other implementations to adapt the AAR plunger to better interface with various sizes, shapes, and styles of drain openings. The AAR plunger can be easily and inexpensively molded, for example from durable rubber or plastic. 
     An operator of an AAR plunger generally unclogs a plumbing fixture drain by placing the plunger into position above a clogged drain such that the plunger head seal interfaces with the opening of the drain. Thus, at least part of the AAR plunger head is surrounded by undrained wastewater. Next, as force is applied downward on the handle, the plunger head compresses, and the portion of the seal in contact with the drain opening forms a mechanical and/or a pressure/suction seal with the drain opening, depending upon the size of the drain opening. Consequently, the pressure generated by compression of the plunger head is directed through the sealing structure and into the drain in the direction of the obstruction. Next, as the handle is then pulled upwards, a suction force is applied to the obstruction in the drain. These upward and downward motions are repeated creating reciprocating pressure and suction forces that dislodge an obstruction from within the drain, thereby facilitating clearing of the drain. 
     More particularly, one exemplary automatic air release plunger implementation includes a handle and a hollow, compressible plunger head. The plunger head is open at both a proximal and distal end, and is coupled to the handle at the proximal end of the plunger head. The plunger head also includes a seal extending from its distal end. This seal is capable of sealing the plunger head to a drain opening of the plumbing fixture. In addition, the handle and plunger head include automatic air release features that allow air to flow along an air-escape path from inside of the hollow plunger head into a void formed in the interior of the handle, and thereafter into a channel which extends from the proximal end of the plunger head to a gap that is open to the exterior of the AAR plunger at a proximal end of the handle whenever the plunger head is compressed. The air ultimately escapes out the gap. The automatic air release features can also in some circumstances allow air to flow from the exterior of the AAR plunger along the same path but in the opposite direction whenever the plunger head is expanded. In this implementation, the proximal end of the plunger head includes a hollow stub having a coupling section that fits within a hollow coupling section forming a proximal portion of the handle. The aforementioned channel includes a slot that begins at a first end of the coupling section of the stub closest to the proximal end of the plunger head and ends at a second end of the coupling section of the stub farthest from the proximal end of the plunger head. In one version, the coupling section of the stub has male treads and the coupling section of the handle has female thread which thread onto the male threads of the stub to couple the handle to the plunger head. In this version, the plunger head stub slot extends from an outermost extent of the male threads inward past the thread roots and into the stub to a depth not penetrating an inner wall of the hollow stub. In addition, the hollow coupling section of the handle includes a ledge at the distal-most end of the hollow coupling section of the handle, the plunger head includes a shoulder located at the distal-most end of the plunger head stub as well as a stop at the proximal-most end of the plunger head stub. The plunger head stop interferes with the handle ledge whenever the handle threads are fully threaded onto the plunger head threads, thereby creating the gap between the plunger head shoulder and the proximal end of the handle. In one implementation, the interference of the stop and the handle ledge also causes the void formed in the interior of the handle to line up with a first end of the plunger head stub slot so that air from the inside of the hollow plunger head can more easily flow into the void and thereafter into the slot whenever the plunger head is compressed. 
     In one implementation, the aforementioned void formed in the interior of the handle includes a void formed by a hollow projection extending from the handle and that opens into the hollow coupling section of the handle. In one version, the location where this void opens into the hollow coupling section of the handle corresponds to a first end of the plunger head stub slot such that air from the inside of the hollow plunger head can more easily flow into the void and thereafter into the slot. In one version, the first end of the plunger head stub slot is made wide enough to ensure that the slot at least partially opens into the void formed in the coupling section of the handle. In another version, the void formed in the coupling section of the handle is made wide enough to ensure the void at least partially opens into the first end of the plunger head stub slot. 
     In one implementation which may not include a threaded connection between the plunger head and the handle, the aforementioned hollow coupling section of the handle includes a ledge at its distal-most end, and the plunger head includes a shoulder located at a proximal-most end of the plunger head stub as well as a stop at the distal-most end of the plunger head stub. The plunger head stop interferes with the handle ledge so as to create the gap between the proximal end of the handle and the shoulder of the plunger head such that air flows from a second end of the plunger head stub slot located at the second end of the coupling section of the stub farthest from the proximal end of the plunger and out of the automatic air release plunger via the gap. 
     In another implementation, the plunger head includes a shoulder located at the proximal-most end of the plunger head stub and a tab projecting toward the handle. The plunger head shoulder tab interferes with the proximal end of the handle so as to create the gap between the proximal end of the handle and the shoulder of the plunger head such that air flows from a second end of the plunger head stub slot located at the second end of the coupling section of the stub farthest from the proximal end of the plunger head and out of the automatic air release plunger via the gap. 
     In yet another implementation, the plunger head includes a shoulder located at a proximal-most end of the plunger head stub, and the handle includes a tab at its proximal end that projects toward the plunger head shoulder. The handle tab interferes with the plunger head shoulder so as to create the gap between the proximal end of the handle and the shoulder of the plunger head such that air flows from a second end of the plunger head stub slot located at the second end of the coupling section of the stub farthest from the proximal end of the plunger and out of the automatic air release plunger via the gap. 
     In another exemplary automatic air release plunger implementation which has multiple air escape paths, the automatic air release features allow air to flow from inside of the hollow plunger head into multiple voids formed in the interior of the handle, and thereafter into multiple channels which extend from the proximal end of the plunger head to a gap that is open to the exterior of the AAR plunger at a proximal end of the handle whenever the plunger head is compressed. The air ultimately escapes out the gap in this implementation as well. The automatic air release features can also in some circumstances allow air to flow from the exterior of the AAR plunger along the same path but in the opposite direction whenever the plunger head is expanded. In this implementation the proximal end of the plunger head includes a hollow stub having a coupling section that fits within a hollow coupling section forming a proximal portion of the handle. The aforementioned multiple channels include multiple slots, each of which begins at a first end of the coupling section of the stub closest to the proximal end of the plunger head and ends at a second end of the coupling section of the stub farthest from the proximal end of the plunger. In one version, the coupling section of the stub has male treads and the coupling section of the handle has female thread which thread onto the male threads of the stub to couple the handle to the plunger head. The hollow coupling section of the handle includes a ledge at its distal-most end, and the plunger head includes a shoulder located at the proximal-most end of the plunger head stub as well as a stop at the proximal-most end of the plunger head stub. The plunger head stop interferes with the handle ledge whenever the handle threads are fully threaded onto the plunger head threads, thereby creating the gap between the plunger head shoulder and the proximal end of the handle. In one implementation, the interference of the stop and the handle ledge also causes each of the voids formed in the interior of the handle to line up with a first end of a different one of the plunger head stub slots so that air from the inside of the hollow plunger head can more easily flow into each void and thereafter into a correspondingly-located slot whenever the plunger head is compressed. In one version, each void formed in the interior of the handle includes a void formed by a hollow projection extending from the handle and that opens into the hollow coupling section of the handle. The location where each void opens into the hollow coupling section of the handle lines up with a first end of a different one of the plunger head stub slots such that, for each void, air from the inside of the hollow plunger head flows into the void and thereafter into the correspondingly-located slot. 
     2.0 Automatic Air Release Plunger 
       FIG. 1  illustrates an exemplary implementation, in simplified form, of an AAR plunger. The AAR plunger depicted in  FIG. 1  is just an example of a suitable implementation and is not intended to suggest any limitation as to the scope of use or functionality. Neither should the AAR plunger depicted in  FIG. 1  be interpreted as having any dependency or requirement relating to any one or combination of the components discussed hereafter in this section. As shown in  FIG. 1 , the exemplary implementation of an AAR plunger  100  includes an elongated handle  102 , an open-ended plunger head  104  coupled to the base (proximal end) of the handle, and a seal  106  extending from the distal end of the plunger head. The plunger head  104  and seal  106  can be made from durable flexible rubber or plastic material. The handle  102  can be made from the same material as the plunger head  104  and seal  106 , or may be made from other materials such as, for example, wood, ceramic, or metal. 
     In the depicted implementation, the plunger head  104  is an elongated pleated bellows  108  which is generally conical and varies in diameter from top to bottom. The bellows  108  has thin walls which define a hollow interior space  110  forming the internal volume of the bellows. Further, the pleats  112  forming the bellows  108  can be of progressively greater flexibility from the top to the bottom. This allows the pleats  112  to easily and smoothly compress and nest together into a relatively small volume during use of the AAR plunger  100 . The flexibility of the pleats  112  also allows the AAR plunger  100  to be adapted to drains in tight or curved spaces, as the bellows will easily bend to fit such spaces. 
     In alternate implementations of the AAR plunger (not shown), the shape and size of the collapsible plunger head may be modified to better accommodate different sizes and shapes of plumbing fixtures. For example, in one alternate implementation, the collapsible plunger head can have a conical pleated bellows which, unlike the plunger head depicted in  FIG. 1 , is of decreasing diameter from top to bottom. This alternate plunger head can also be both longer and narrower in diameter than the plunger head depicted in  FIG. 1 . The alternate plunger head can be, for example, better suited for use in smaller sinks and basins, such as are typically found in household bathrooms. Further, in other implementations, the collapsible plunger head can take the form of various conventional non-bellows configurations (such an inverted flexible cup) or a combination of a non-bellows and bellows configurations. As long as the plunger head has sufficient internal volume to produce satisfactory pressure and suction forces when compressed and expanded, the size and shape of the plunger head may be varied without affecting it&#39;s performance, usability or durability. For example, the plunger head may take such shapes as a sphere, an oval, a cone, a pyramid, or it may have a rectangular cross-section, or it can have a shape which is any combination of these shapes. Further, the plunger head may also comprise fanciful shapes, or any other practical shape which is pleasing. 
     The plunger head seal  106  depends from the bottom of the bellows  108  as illustrated in the implementation depicted in  FIG. 1 . The seal  106  has flexible walls with a generally annular shape and a narrow bottom end or “mouth”  114  adapted to be inserted into or over a typical plumbing fixture drain opening. The mouth  114  opens into the interior of the bellows  110  to alternately direct a pressurized wastewater flow into, then out of, the drain as the AAR plunger  100  is first compressed then expanded. In one implementation the seal  106  is relatively less flexible than the pleats  112 , but is sufficiently flexible to deform inwardly when the AAR plunger  100  is inserted into a typical drain opening (such as in a toilet) to form an interference fit type mechanical seal with the walls defining the drain opening. Further, the bottom end of the seal  106  is flat. This provides the capability for the seal  106  to form a pressure seal with a surface surrounding a drain opening which is smaller in diameter than the mouth  114  of the seal. For the purpose of this disclosure, the term “pressure seal” will mean a pressure and suction or vacuum seal. The pressure seal is in effect when the AAR plunger is being compressed, and the suction or vacuum seal is in effect when the AAR plunger is being expanded. Note that the seal  106  can be formed of the same materials as the bellows  108 , but of relatively different proportions of those materials than for the bellows so as to control its flexibility. Alternately, the seal  106  can be formed of the same materials using the same composition as the bellows  108 , but of a relatively different thickness than the bellows so as to control its flexibility relative to the bellows. Alternate seal designs and shapes can be used in various other implementations to adapt the AAR plunger to better interface with various sizes, shapes, and styles of plumbing fixture drain openings. 
     As illustrated by  FIG. 1 , the handle  102  is releasably connected to the plunger head  104 . Any of a number of types of releasable connections may be used. For example, as illustrated by  FIG. 1 , the handle  102  is threadably coupled to the plunger head  104 . In other implementations, the handle  102  is releasably coupled to the plunger head  104  via a snap-fit mechanism or cotter pin. In still further implementations, the handle  102  is instead permanently attached to the plunger head  104  by conventional methods such as, for example, an integrally molded handle, or a handle permanently glued, riveted, or otherwise attached to the head. 
     In the aforementioned threaded implementation, as depicted in  FIG. 2 , the plunger head  204  has a threaded stud  216  extending from its top (proximal) end. The handle  202  is hollow at its proximal end  218  with threads  220  formed on its inner surface to receive the plunger head&#39;s threaded stud  216 . In particular, in this implementation, the threaded stud  216  is open on both ends, thereby forming an open pathway or channel extending from the seal  206  through the plunger head  204 , then through the threaded stud and into the hollow end  218  of the handle  202 . The distal end  222  of the handle  202  is formed into an expanded knob  224  adapted to comfortably rest in an operator&#39;s palm when using the AAR plunger  200 . Further, in another implementation, the distal end  222  of the handle  202  is ribbed to allow the operator to maintain a non-slip grip on the handle during operation. In one implementation, the handle  202  is hollow, whether permanently or releasably attached, having a central space therein to reduce its weight. In other implementations, the handle is solid throughout (with the exception of the internally threaded portion thereof), or is a combination of hollow and solid sections. 
     2.1 Automatic Air Release Features 
     The automatic air release features of the handle and plunger head of the AAR plunger are integrated into the overall plunger configuration and jointly release air from within the interior of the plunger head during compression of the plunger. For example, as applied to the implementation depicted in  FIG. 3 , the handle  302  is configured so that it “bottoms-out” when fully threaded onto the plunger head  304 . In this bottomed-out position, a small gap  326  is left between the proximal end of the handle  302  and a shoulder  328  on the plunger head  304  located at the proximal end of the male threads  330  that screw into the female threads  332  at the proximal end of the handle. In the depicted implementation, the gap  326  exists because a ring-shaped stop  334  at the distal end of the plunger head&#39;s threaded stub  316  abuts an interior ledge  336  located at the inboard (distal) end of the handle threads  332 . Air escapes out of the gap  326  as will be described in more detail in the paragraphs to follow. 
     The male threads  330  of the plunger head  304  include one or more slots  338 . As better seen in  FIG. 4 , a first end  440  of each slot  438  is located at or just above the most distal male thread of the threaded stub  416  of the plunger head  404  and can be separated along the circumference of that threaded stub from other slot(s) (if there are more than one). The second end  442  of each slot is located at the bottom edge of the most proximal male thread of the threaded stub  416  and can separated along the circumference of that threaded stub from other slot(s) (if there are more than one). In one implementation having multiple slots, each slot is positioned equidistant from adjacent slots along the circumference (see  FIGS. 5 and 6 ). In one implementation, as shown in  FIG. 4 , each slot  438  follows a straight line from the most distal male thread to the most proximal male thread, however this is not a requirement and a slot can follow any track through the threads (e.g., stepped, spiral, curved, and so on). The slots could even intersect other slots along their tracks through the threads. As best seen in  FIG. 3 , the depth of each slot  338  is such that it extends beyond the root of the threads  330  but not as far as the interior wall of the plunger head stub  316 . The slots&#39; depth can also vary along its track through the threads as long as each slot extends some distance beyond the root of the threads. When the female threaded portion of the plunger handle  302  is threaded onto the male threaded portion of the plunger head stub  316 , the part of the slot  338  extending past the plunger head threads forms a channel through which air can flow. The width of each slot along the circumference of the plunger head stub can be any distance that when considered in conjunction with the width any other slots does not jeopardize the treaded attachment strength to the point that the handle would pull loose from the plunger head during an unclogging operation. A slot can also vary in width along its track through the threads. It is noted that the combination of the depth of the slot and its width at any point along its track through the threads dictates the cross-sectional area of the slot at that point. The point along a slot having the smallest cross-sectional area determines the amount of air that moves through the slot during an unclogging operation. Ultimately, the number of slots and their smallest cross-sectional areas control the amount of air that exits (or enters) the hollow interior of the plunger head during an unclogging operation. 
     Referring to  FIG. 3  once again, there is a projection  344  ( 144  in  FIG. 1 ) along the circumference of the exterior part of the proximal portion of the plunger handle  302 . The projection  344  is hollow and forms a void  346  in the inner wall of the handle  302  inboard of and opening into the interior ledge  336  of the handle. In some implementations, the projection  344 /void  346  lines up with the first end  340  of a slot at or just above the most distal male thread of the threaded stub  316  of the plunger head  304 . In one implementation, this is accomplished by configuring the ring-shaped stop  334  at the distal end of the male threaded stub  316  of the plunger head  304  so that it contacts the interior ledge  336  of the handle  302  in a manner that prevents further rotation of the handle onto the plunger head  304  at a rotational position where the plunger head slot  338  lines up with a corresponding handle projection void  346 . In other implementations not employing a threaded connection between the handle and plunger head, the alignment of each plunger head slot with a corresponding handle projection void is accomplished in an appropriate manner. Ideally, the centerline of the plunger head slot  338  at or just above the most distal male thread of the threaded stub  316  would align with the centerline of the corresponding handle projection void  346 . However, some misalignment can be tolerated as long as the air-escape path is not compromised to an unacceptable degree (e.g., the total amount of air flow from the interior of the plunger head is less than desired). In one implementation shown in  FIG. 7 , this issue is addressed by making the width of a plunger head slot  738  at or just above the most distal male thread of the threaded stub  716  of the plunger head wide enough to allow for a reasonable amount of rotational misalignment. In another implementation shown in  FIG. 8 , the misalignment issue is addressed by making the circumferential width of the handle projection void  846  wide enough to allow for a reasonable amount of rotational misalignment. In some implementations (such as shown in  FIG. 9 ), both the width of the plunger head slot  938  and the handle projection void  946  are made wide enough to allow for a reasonable amount of rotational misalignment. 
     The foregoing alignment allows air to more easily flow from the inside of the hollow plunger head  304  into the handle  302 , then between the interior surface of the handle above its proximal-most thread and the exterior surface of the plunger head stub  316  above its distal-most thread during compression of the plunger head. It is noted that air does not flow into the mating threads of the handle and plunger head stub because the threads form a substantially air-tight seal. Instead, air then flows into the void  346  and through the plunger handle&#39;s interior ledge  336 . In some implementations, the void  346  interfaces with the slot  338  in the male threads  330  of the plunger head  304 . Thus, the void  346  allows air to directly enter the slot  338 . The air then follows the slot  338  and exits the AAR plunger  300  via the gap  326  between the plunger head shoulder  328  and the proximal end of the handle  302 . During expansion of the plunger head, air flows along the same air-escape path, but in the reverse direction. The air-escape path is shown by the two-way path line  348  in  FIG. 3 . It is noted that even if the handle void did not line up with the plunger head stub slot, air would still enter the cylindrical-shaped space between the interior surface of the handle above its proximal-most thread and the exterior surface of the plunger head stub above its distal-most thread, and eventually find its way to the plunger head stub slot. However, this cylindrical-shaped space can be narrow and thereby restrict the flow of air compared to implementations where the handle void(s) line up with the plunger head stub slot(s). 
     In some implementations with multiple plunger head stub slots, there is a corresponding handle projection/void for each slot. More particularly, implementations with two slots  538  and two projection voids  546 , or three slots  638  and three projection voids  646  (as shown in  FIGS. 5 and 6 , respectively) are envisioned. Note that in  FIGS. 5 and 6 , the handle and plunger head stub are shown in a rotationally misaligned condition so that both the slots and voids can be seen. Further, while not shown in the figures, even more than 3 slots are possible in some implementations, as long as the combined width of the slots does not jeopardize the connection between the handle and the plunger head. 
     3.0 Automatic Air Release Plunger Operation 
     An operator of an AAR plunger generally unclogs a plumbing fixture drain by placing the plunger into position above a clogged drain such that the plunger head seal interfaces with the opening of the drain. Thus, at least part of the AAR plunger head is surrounded by undrained wastewater. The previously-described automatic air release features of the AAR plunger provide a considerable advantage during the insertion of the plunger into a clogged plumbing fixture. When the AAR plunger is inserted into the undrained wastewater and pushed toward the drain opening, the wastewater exerts a force on the air trapped inside the hollow plunger head. The automatic air release features allow the air inside the plunger head to escape in a controlled manner, thus allowing wastewater to begin filling the plunger head. More particularly, air from inside the plunger head flows out of the open end of the plunger head stub and into the handle. Air then flows between the interior surface of the threaded portion of the handle and the exterior surface of the plunger head stub, and from there through the one or more handle projection voids, then through the handle ledge and into one or more of the slot(s) in plunger head stub. The air then exits the AAR plunger via the previously-described gap between the plunger head shoulder and the distal end of the handle. Absent this release of air from the plunger head, the volume of the plunger head structure and the air trapped inside the plunger head would cause a significant rise in the undrained wastewater level within the plumbing fixture owing to displacement of the wastewater. The rise in wastewater level could result in it overflowing from the fixture onto surrounding surfaces and floor—an occurrence often referred to as “spillover”. 
     In one implementation of the seal, such as illustrated in  FIG. 1 , as the seal  106  is inserted into the drain opening of the clogged plumbing fixture, the seal deforms to form a pressure seal with the edges of the drain opening and the surface surrounding the drain opening. The deformation of the seal  106  thus creates an interference fit/mechanical seal and a pressure seal between the seal and the drain opening. As the operator pushes down on the handle  102 , the plunger head  104  is compressed. The pressure generated by compression of the plunger head  104  is directed through the seal  106  and into the drain in the direction of the obstruction that is clogging the drain. As the plunger head  104  is compressed, the automatic air release features facilitate a controlled release of the air still remaining air in the hollow interior of the plunger head as described previously. This controlled release of air prevents the undrained wastewater in the plumbing fixture from being excessively churned as could occur if there were no automatic air release features and the air-water mixture inside the head instead escapes suddenly from between the drain opening and the plunger head seal  106 . Excessive churning of the wastewater could result in some of it escaping the plumbing fixture—an occurrence often referred to as “backsplash”. In addition, in implementations where the plunger head is completely or partially formed from a bellows, the plunger tends to bend at an angle to the drain on the compression stroke if the air inside the plunger head cannot escape, thereby potentially causing churning of the wastewater in the plumbing fixture and a backsplash. The automatic air release features prevent this from occurring. 
     Next, the handle  102  is then pulled upwards. This expands the plunger head  104  and applies a suction force on to the obstruction in the drain. The suction force in the drain enhances the pressure seal between the seal  106  and the drain opening, thereby preventing the plunger from lifting away from the drain. In addition, the automatic air release features allow some air to re-enter the plunger head via the foregoing path in the reverse direction. 
     The downward and upward motions of the handle  102  are repeated creating reciprocating pressure and suction forces that dislodge the obstruction from within the drain. The dislodged obstruction then is typically is drawn down the drain pipe when the plunger is removed, thus clearing of the drain. 
     The automatic air release features have a further advantage of ensuring that the plunger head is mostly filled with wastewater during each compression stroke and that there is little or no air upstream from the obstruction in the drain during each expansion stroke. The fact that the air initially residing inside the hollow plunger head is released as described above and replaced with wastewater has the advantage of placing a much stronger pressure force on the obstruction that would air (or a mixture of mostly air with some water) during a compression stroke owing to the greater weight and greater incompressibility of the water. The same is true when the plunger head is expanded during an unclogging operation as the water&#39;s higher incompressibility will cause a stronger suction force to be exerted on the obstruction than would with air (or a mixture of mostly air with some water). 
     It is noted that the speed at which the plunger head is initially compressed during an unclogging operation should ideally be such that the undrained water in the plumbing fixture is not agitated to a degree that some of it spills out. This compression speed will at least partially depend on the amount of air displaced from the interior of the hollow plunger head over time via the previously-described air-escape path. The amount of air displaced per exit point over time during the initial compression stroke is generally dependent on the narrowest cross-sectional part of each of the air-release paths. It is also noted that generally, the more air displaced over time during the initial compression stroke of an unclogging operation, the faster the compression stroke can be accomplished, thereby potentially making the unclogging operation easier for the operator of the plunger. However, during the expansion stroke of the unclogging operation, some air can be drawn into the hollow interior of the plunger body through each of air-release path. As long as the amount of water/air drawn in through the air-release path(s) does not significantly affect the amount of water drawn in to the hollow interior of the plunger body from the drain of the sink or toilet being unclogged to the point that the suction force exerted on the drain obstruction is unacceptably diminished. 
     It is also noted that some of the water drawn inside of the hollow plunger body might follow the previously described air-release path and exit via the gap between the plunger head&#39;s shoulder and the proximal end of the handle during depression of the plunger body. However, this water will be directed sideways into the plumbing fixture (as opposed to upward and possibly out), and of no significance as long as the amount of water directed out through the air-release path(s) does not significantly affect the amount of water pushed into the clogged drain from the hollow interior of the plunger body to the point that the pressure force exerted on the drain obstruction is unacceptably diminished. 
     4.0 Additional Implementations 
     While the AAR plunger described so far employs a ring-shaped stop at the distal end of the male threaded stub of the plunger body to abut the interior ledge located at the inboard end of the handle threads, a shoulder tab feature can be employed in conjunction with or in lieu of the ring-shaped stop. In one implementation, the shoulder tab feature takes the form of one or more projections originating from the shoulder of the plunger head and directed generally perpendicular to the shoulder. Each projection has a length that when it abuts the proximal end of a fully installed plunger handle creates the desired gap between the proximal end of the handle and the shoulder of the plunger head. Air can escape out of the gap as described previously.  FIG. 10  shows one implementation where a single shoulder tab  1048  extends from the shoulder  1028  of the plunger head  1004 .  FIG. 11  illustrates the gap  1126  formed by the shoulder tab  1148  when the handle  1102  is fully installed on the plunger head  1104 . In yet another implementation (not shown in the figures), the shoulder tab projects from the proximal end of the handle instead of from the shoulder of the plunger head. The resulting gap is the same. 
     Referring now to  FIG. 12 , in yet another implementation, the previously-described alignment issue between the plunger head slot(s) and handle&#39;s projection/voids is eliminated by replacing the individual handle projection(s) with a ring-shaped projection  1250  having an interior void  1252  that wraps around the circumference of the handle  1202  and which opens into the space  1254  between the interior surface of the handle  1202  above its proximal-most thread and the exterior surface of the plunger head stub  1216  above its distal-most thread. In this way, the exact rotational alignment of a plunger head slot  1238  with the handle  1202  becomes irrelevant. In other words, no matter where the slot  1238  (or slots if there are more than one) aligns with the handle  1202 , a relatively larger air-release path is created through the handle&#39;s ring-shaped projection void  1252  so that air from the interior of the plunger head  1204  can enter the slot and exit out the gap  1226  between the proximal end of the handle and a shoulder  1228  on the plunger head. Additionally, in this implementation, the previously-described shoulder tab  1248  is employed rather than the previously-described ring-shaped stop at the distal end of the plunger head stub  1216  to create the air-escape gap  1226 . This air-escape path is shown by the two-way path line  1248  in  FIG. 12 . 
     Referring now to  FIG. 13 , in yet another implementation, the previously-described alignment issue between the plunger head slot(s) and handle&#39;s projection/voids is eliminated by replacing the individual handle projection(s) with an annular indentation  1350  that wraps around the circumference of the plunger head stub  1316  close to its distal end and which opens into the space  1354  between the interior surface of the handle  1302  above its proximal-most thread and the exterior surface of the plunger head stub  1316  above its distal-most thread. In this way, the exact rotational alignment of a plunger head slot  1338  with the handle  1302  becomes irrelevant. In other words, no matter where the slot  1338  (or slots if there are more than one) aligns with the handle  1302 , a relatively larger air-release path is created through the annular indentation  1350  so that air from the interior of the plunger head  1304  can enter the slot and exit out the gap  1326  between the proximal end of the handle and a shoulder  1328  on the plunger head. Additionally, in this implementation, the previously-described shoulder tab  1348  is employed rather than the previously-described ring-shaped stop at the distal end of the plunger head stub  1316  to create the gap  1326 . The resulting air-escape path is shown by the two-way path line  1348  in  FIG. 13 . 
     It is also noted that although the foregoing subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims. 
     What has been described above includes example implementations. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the claimed subject matter, but one of ordinary skill in the art may recognize that many further combinations and permutations are possible. Accordingly, the claimed subject matter is intended to embrace all such alterations, modifications, and variations that fall within the spirit and scope of the appended claims. 
     The aforementioned implementations have been described with respect to interaction between several components. It will be appreciated that such implementations and components can include those components or specified sub-components, some of the specified components or sub-components, and/or additional components, and according to various permutations and combinations of the foregoing. Sub-components can also be implemented as components coupled to other components rather than included within parent components (e.g., hierarchical components).