PLUNGER

Information

  • Patent Application
  • 20240337095
  • Publication Number
    20240337095
  • Date Filed
    April 10, 2024
    7 months ago
  • Date Published
    October 10, 2024
    a month ago
  • Inventors
    • Porat; Yair (Van Nuys, CA, US)
    • Fields; Blaine (Santa Monica, CA, US)
Abstract
Embodiments of the present disclosure are directed to plungers for clearing plumbing clogs, such as clogs or obstructions in toilets and drains. The shape and size of the footprint (i.e. area occupied) of the plunger of the present disclosure is different and unique compared to that of any existing plunger. The rear section of the plunger footprint (which sets towards the rear of the toilet bowl drain opening) is circular in shape, while the front section of the footprint takes an elliptical shape. The size and shape of this footprint provides more coverage of the toilet bowl drain area in the majority of toilets, resulting in a tighter seal over the drain area, and subsequently creating better suction than existing plungers, when operating the plunger.
Description
TECHNICAL FIELD

The present disclosure generally relates to an apparatus for removing obstructions from a toilet bowl, drainpipe and, more particularly, to toilet plungers.


BACKGROUND

A plunger is a well-known tool used to clear blockages or clogs in drains and pipes. Typically, plungers are used to remove the blockages in sinks, drains, and toilets. Toilet and drain clogs may sometimes be cleared with various plunger models currently on the market. However, quite a lot of force is often required. Some clogs are not able to be cleared with the use of current plungers, in which case a plumber's drain snake line is next employed in an attempt to clear the clog. Additionally, existing plungers do not provide adequate/enough suction to clear the clog and operation of the plunger often results in the splashing of water out of the toilet bowl or drain onto the user. The water may contain unsanitary waste material which is then splashed onto the user.


Another means for clearing clogs is through use of chemical products, which are poured into the toilet bowl or drain, and which work over time to dissolve the matter clogging the toilet or drain. However, this method requires time for the chemicals to work, and does not always result in the clog being cleared (even when a plunger is used after use of the chemical product).


In view of the above, what is needed is a plunger which is more effective than existing plungers for clearing clogs in toilets and drains. More specifically, a plunger which is more effective at clearing clogs when the equivalent amount of force is applied as used with existing plungers. Also, what is needed is an improved plunger resulting in less agitation/movement of the water around and above the plunger footprint, which greatly decreases the splashing of water (splash back), which in-turn makes the plunger more hygienic to use than existing plungers.


SUMMARY

The following presents a simplified summary of one or more implementations in order to provide a basic understanding of some implementations. This summary is not an extensive overview of all contemplated implementations and is intended to neither identify key or critical elements of all implementations nor delineate the scope of any or all implementations. Its sole purpose is to present some concepts of one or more implementations in a simplified form as a prelude to the more detailed description that is presented later.


According to one example, a plunger is provided. The plunger comprises an elongated handle having a first end and an opposing second end; a cup connected to the second end of the elongated handle; and a flange integrally connected to the cup, where the flange is a continuous section extending downward from inside of the cup creating a tight seal against a vertical surface of a drain. The cup comprises a front-end portion having a generally elliptical shape; and a rear-end portion having a generally circular shape, where the front-end portion and the rear-end portion form a tear drop shape.


According to one aspect, a top of the elongated handle has a T-shaped grip.


According to another aspect, the flange further comprises a front-end wall extending upwardly and outwardly into the front-end portion of the cup; and a back-end wall extending upwardly and outwardly into the rear-end portion of the cup; and where the front end-wall and the back-end wall are integrally connected forming a side wall of the flange.


According to yet another aspect, the outwardly projecting front-wall end forms a recess allowing the cup to sit at or above a drain reducing an occurrence of water splashing back during use.


According to yet another aspect, the flange has a circular shape.


According to yet another aspect, the cup and the flange are made of an elastomeric material.


According to yet another aspect, the elastomeric material is rubber.


According to another example, a plunger assembly is provided. The plunger assembly comprises a cover having an elongated inner handle; a cup section integrally connected to the elongated inner handle; a plunger configured to be received within the cover, the plunger comprising an elongated outer handle having a first end and an opposing second end; a cup connected to the second end of the elongated handle, the cup comprising a dome; and a flat member integrally connected to the dome, the dome having an elliptical shape; and a flange integrally connected to, and extending downwardly from, the cup. The cover is configured to be placed over the plunger to protect the plunger, the elongated outer handle is configured to be received in the elongated inner handle, and the cup section is configured to receive the cup of the plunger.


A plunger assembly is provided. The plunger assembly comprises a cover having an elongated inner handle; a cup section integrally connected to the elongated inner handle; a plunger configured to be received within the cover, the plunger comprising an elongated outer handle having a first end and an opposing second end; a cup connected to the second end of the elongated handle, the cup comprising a dome; and a flat member integrally connected to the dome, the dome having an elliptical shape; and a flange integrally connected to, and extending downwardly from, the cup. The cover is configured to be placed over the plunger to protect the plunger, the elongated outer handle is configured to be received in the elongated inner handle, and the cup section is configured to receive the cup of the plunger.


According to one aspect, the flange is located in a same vertical plane as the dome.


According to another aspect, the cup and the flange are made of an elastomeric material.


According to yet another aspect, the elastomeric material is rubber.


According to another example, a plunger is provided. The plunger comprises an outer handle; an inner handle, the outer handle configured to slideably receive the inner handle; an upper membrane connected to the outer handle; a lower membrane connected to the upper membrane and the inner handle; where the inner handle moves vertically within the outer handle; and where moving the inner handle in an up and down motion actuates the lower membrane displacing liquid within a drain.


According to one aspect, the outer handle is stationary.


According to another aspect, the upper and lower membranes are made of rubber.


According to yet another aspect, the upper and lower membranes are made of silicone.


According to yet another aspect, the upper and lower membranes are made of a semi-flexible material.


According to yet another aspect, the lower membrane is less rigid than the upper membrane.





BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 is a side view of a plunger according to one aspect of the present disclosure.



FIG. 2 is a back-end view of the plunger of FIG. 1.



FIG. 3 is a cross-sectional view of the plunger in FIG. 2 taken along line 3-3.



FIG. 4 is an enlarged view of the area of detail designated in FIG. 3 illustrating a connecting member on the plunger.



FIG. 5 is a bottom view of the plunger of FIG. 1.



FIG. 6 is a top, right perspective view of the plunger of FIG. 1.



FIG. 7 illustrates a partial top, left perspective view of a plunger according to another aspect of the present disclosure.



FIG. 8 illustrates a partial bottom, left perspective view of the plunger of FIG. 7.



FIG. 9 is a side view of a plunger assembly according to another aspect of the present disclosure.



FIG. 10A illustrates a side view of a plunger in an expanded configuration according to another aspect of the present disclosure.



FIG. 10B illustrates a side view of the plunger of FIG. 10A in a contracted configuration.



FIG. 11 illustrates a top view of a plunger having a footprint which widens at the rear corners of the plunger.





DETAILED DESCRIPTION

In the following description, specific details are given to provide a thorough understanding of the described implementations. However, it will be understood by one of ordinary skill in the art that the implementations may be practiced without these specific details. For example, certain aspects may be illustrated with simplified representations in order not to obscure the implementations in unnecessary detail. In other instances, well-known techniques may be shown in broad block form in order not to obscure the described implementations.


Overview

Embodiments of the present disclosure are directed to plungers for clearing plumbing clogs, such as clogs or obstructions in toilets and drains. The shape and size of the footprint (i.e. area occupied) of the plunger of the present disclosure is different and unique compared to that of any existing plunger. The rear section of the plunger footprint (which sets towards the rear of the toilet bowl drain opening) is circular in shape, while the front section of the footprint takes an elliptical shape. The size and shape of this footprint provides more coverage of the toilet bowl drain area in the majority of toilets, resulting in a tighter seal over the drain area, and subsequently creating better suction than existing plungers, when operating the plunger.


This unique footprint size and shape also results in less agitation/movement of the water around and above the plunger footprint, thereby greatly reducing the occurrence of water splashing out of the toilet bowl (splash back) during use.


Because this improved plunger is more effective at clearing clogs when the equivalent amount of force is applied as when using current/prior art plungers, it is more efficient and therefore easier for people to use, especially those persons having less strength (such as seniors, for instance, since the plunger is more effective when using even less force as compared to existing plungers).



FIG. 1 is a side view of a plunger 100 according to one aspect of the present disclosure. FIG. 2 is a back-end view of the plunger 100 of FIG. 1. FIG. 3 is a cross-sectional view of the plunger 100 in FIG. 2 taken along line A-A. FIG. 4 is an enlarged view of the area of detail designated in FIG. 3 illustrating a connecting member on the plunger. FIG. 5 is a bottom view of the plunger 100 of FIG. 1. FIG. 6 is a top, right perspective view of the plunger of FIG. 1. The following discussion refers interchangeably to FIGS. 1-6.


As shown, the plunger 100 includes an elongated handle 102, having a first end 102a and an opposing second end 102b, connected to a cup 106. The plunger 100 may further include a flange 108 integrally connected to the cup 106, the flange 108 being a continuous section extending downward from the inside of the cup 106 to create a tighter seal against the vertical surface of the drain or toilet drain. The cup 106 and flange 108 may be made of an elastomeric material such as rubber, and formed in a molding process, for example. Alternatively, the cup 106 and flange 108 may be made from any material known in the art.


The cup 106 includes a front-end portion 106a having a generally elliptical shape and a rear-end portion 106b having a generally circular shape, the front-end portion 106a and the rear-end portion 106b forming a generally tear drop shape. The flange 108 may have a generally circular shape or any other shape the forms to the shape of the drain. In one aspect, the flange 108 includes a front-end wall 108a extending upwardly and outwardly into the front-end portion 106a of the cup 106 and a back-end wall 108b extending upwardly and outwardly into the rear-end portion 106b of the cup 106. As shown, the back-end wall 108b extends outwardly in an opposite direction than the front-end wall 108a extends outwardly. The front-end wall 108a and the back-end wall 108b are integrally connected forming the side wall of the flange 108. In one aspect, the outwardly projecting front-end wall 108a forms a recess allowing the cup 106 to sit at or slightly above a drain, such as a toilet drain, reducing the occurrence of water splashing back during use.


With respect to the flange 108, the flange 108 may be operable between an operating position and a stowed position within the plunger cup. That is, the flange 108 may be flipped or turned down (operating position) or stored internally within the cup 106 (stowed position). Alternatively, the flange 108 may be permanently fixed in a position extending downward from the plunger footprint.


Turning to FIG. 4, an enlarged view of the area of detail of the elongated handle 102 connecting to the cup 106 is shown. As shown, the elongated handle 102 may be threadingly engaged to the cup 106. Alternatively, the elongated handle 102 may be detachably or permanently affixed to the cup 106 by any means known in the art. The top of the elongated handle 102 may have a T-shaped grip, a ball-shaped grip, or other shape grip providing an enhanced ergonomic grip to allow for a firm and comfortable grip when operating the plunger 100.


While the flange 108 is shown as a concave shape, in alternative embodiments, the flange 108 may be convex in shape (when unengaged with the toilet drain) or may be able to flex from convex shape to concave as it is engaged with the toilet drain.



FIGS. 7-8 illustrate a plunger 200 according to another aspect of the present disclosure. As shown, the plunger 200 includes an elongated handle 202, having a first end 202a (not shown) and an opposing second end 202b, connected to a cup 206. The cup 206 may be comprised of a dome 206a integrally connected to a flat member 206b. The flat member 206b may have a generally elliptical shape that extends horizontally outward from the dome 206a. However, in alternative embodiments, the flat member 206b may be other shapes, such as ovals, triangles, squares, or other polygons.


The plunger 200 may further include a flange 208 integrally connected to the cup 206. As shown in FIG. 8, the flange 208 may be integrally connected to, and extend downwardly from, the rear-most section of the flat member 206b. According to one embodiment, the flange 208 may be located in the same vertical plane as the dome 206a.


The flange 208 creates a tight seal against vertical surface of the drain or toilet drain. The cup 206 and flange 208 may be made of an elastomeric material such as rubber, and formed in a molding process, for example.


While the flange 208 is shown as a concave shape, in alternative embodiments, the flange 208 may be convex in shape (when unengaged with the toilet drain), or able to flex from convex shape to concave as it is engaged with the toilet drain.


Fixed Cover Design


FIG. 9 is a side view of a plunger assembly 300 according to another aspect of the present disclosure. The plunger assembly 300 includes a cover 303 and a plunger 302, where the plunger 302 is configured to be received within cover 303.


The plunger 302 comprises an elongated inner handle 307 having a first end 307a and an opposing second end 307b connected to a cup 306. The cup 306 may be comprised of a dome 306a integrally connected to a flat member 306b. The flat member 306b may have a generally elliptical shape that extends horizontally outward from the dome 306a. However, in alternative embodiments, the flat member 306b may be other shapes, such as ovals, triangles, squares, or other polygons.


The plunger 302 may further include a flange (not shown) integrally connected to the cup 306. Similar to the plunger 200 in FIG. 8, the flange of the plunger 302 in FIG. 9 may be integrally connected to, and extend downwardly from, the rear-most section of the flat member 306b. According to one embodiment, the flange may be located in the same vertical plane as the dome 306a. The cup 306 and flange may be made of an elastomeric material such as rubber, and formed in a molding process, for example. Alternatively, the cup 306 and flange may be made from any material known in the art.


The cover 303 may comprise an elongated inner handle 307 integrally connected to a cup section 305. The cover 303 is configured to be placed over the plunger 302 to protect the plunger 302, where the elongated inner handle 307 is configured to receive the elongated outer handle 304 and the cup section 305 is configured to receive the cup 306 of the plunger 302. In one aspect, the elongated outer handle 304 is stationary.


When in place, the cover 303 may sit above the flat member 306b. In one aspect, the upper/outer edge the cup 306 may be connected to the bottom edge of the cover 303 so that water cannot enter between the cover 303 and the plunger 302.


The plunger assembly 300 may be operated by a user simultaneously placing one hand on the upper part of the outer handle 304, which allows the entire plunger assembly 300 to be held securely in place at the toilet drain, and placing the other hand at the top of the inner handle 307a, which can then be operated in a smooth up and down motion in order to actuate the plunger 302 to displace the water in the toilet bowl drain area with air pressure generated by the plunger motion. The inner handle 307 may move freely within the stationary outer handle 304 of the cover 303.


The fixed cover 303 provides for the outer edge/perimeter of the plunger footprint to be held securely in place with a consistent downward force, without lifting away from the toilet bowl, especially when the plunger motion is in the pulling-up cycle of the operation (during which motion a standard plunger often loses suction due to part or all of the plunger perimeter lifting away from the toilet bowl).


Furthermore, the cover 303 may aid in further decreasing the agitation of the water around the plunger footprint perimeter when the plunger 302 is being used, as the cup 306 is sealed under the cover 303 and does not come into contact with the water. This is beneficial when there is greater than usual volume of standing water in the toilet bowl, where the cup 306 would otherwise (if not in a sealed cover) agitate/displace the water above the plunger footprint.


The air pressure generated between the outside of the cup 306 and the cover 303 may be forced out through the top of the outer handle 304 with minimal resistance as the plunger 302 is operated, so that no vacuum is created between the cup 306 and cover 303.


According to another aspect, the upper portion of the outer handle 304 may include a pattern of holes or other means to facilitate the movement of air.


Inverted Plunger Design

According to another aspect, a plunger 400 is provided that allows for the vertical movement (or plunger action) of the plunger 400 to occur predominantly below the footprint of the plunger 400 and within the recess of a toilet drain and below the waterline. FIG. 10A and FIG. 10B illustrate sides views of the plunger 400 in expanded and contracted configurations, respectively.


The plunger 400 may include an outer handle 402 and an inner handle 404, where the outer handle 402 is configured to slideably receive the inner handle 404.


The plunger 400 further includes an upper membrane 406 and a lower membrane 408, where the lower membrane 408 is connected to the upper membrane 406 at the footprint of the upper membrane 406, such that the upper membrane 406 and footprint covers the toilet drain opening.


As shown, extending below the bottom perimeter edge of the upper membrane 406 is the lower membrane 408 which forms into a boot of sorts at the most extended (or expanded) portion (being somewhat of an upside-down plunger cup, though with a dimension which fits into most toilet drain recesses). Both the upper and lower membranes 406, 408 may be made of rubber, silicone, or similar semi-flexible material providing the desired combination of rigidity and flexibility.


In one aspect, the upper membrane 406 may be rigid around the perimeter of the footprint, as well as across the top, providing sufficient rigidity to keep a good seal over the toilet drain area. The upper membrane 406 is connected to the outer handle 402. In one aspect, the outer handle 402 is stationary. The lower membrane 408 may be less rigid than the upper membrane 406 and attached within the bottom inside of the lower membrane to the inner handle 404.


In operation, the user simultaneously placing one hand on the upper part of the outer handle 402 allows the entire assembly to be held securely in place at the toilet drain, and placing the other hand at the top of the inner handle 404, which can then be operated in a smooth up and down motion in order to actuate the inverted rubber plunger and thereby displace the water in the toilet bowl drain area with the mass of the plunger footprint. The inner handle 404 may move freely within the stationary outer handle 402. When the inner handle 404 is pulled all the way upwards, the plunger foot is drawn up largely within the upper membrane 406, allowing for a sufficient range of motion to create adequate suction below the of the upper membrane 406 footprint.


As the outer handle 402 is affixed to the more rigid upper membrane 406, the outer edge/perimeter of the plunger footprint can be held securely in place with a consistent downward force, without lifting away from the toilet bowl, especially when the plunger motion is in the pulling-up cycle of the operation.


The plunger 400 of FIG. 4 may also aid in further decreasing the agitation of the water around the plunger footprint perimeter when the plunger 400 is in use, since the upper membrane 406 only slightly flexes, and only the lower membrane 408, below the footprint, moves up and down. As with the previously described embodiment design, this is especially helpful when there is greater than usual volume of standing water in the toilet bowl, where the plunger cup would otherwise (if not in a sealed cover) agitate/displace the water above the plunger footprint.


Although this alternative design does not allow for a flange as in the other embodiments described previously, by virtue of the design of the lower membrane 408, a tight seal within the toilet drain is further enhanced (in addition to the seal created by the footprint, in each of these embodiments) by way of the lower membrane 408 being actuated with the inner handle 404. As the lower membrane 408 is pushed downwards, the sloping angle of the lower membrane wall (at the upper sides of that wall), presses/engages against the surfaces of the drain opening, and such seal is maintained while the inner handle 404 is further depressed, allowing the inverted plunger cup to displace the water below the aforementioned seal created at the drain opening.


Furthermore, the air pressure generated between the upper and lower membranes 406, 408 as the plunger 400 is in operation, is forced out through the top of the outer handle 402 (as with the previous embodiment), so that no vacuum is created between the upper membrane 406 and lower membrane 408.


Regardless of the overall design/embodiment, the plunger 400 may incorporate a more pliant section running along the perimeter edge of the plunger footprint, which flexibility can make for a tighter seal against varying toilet bowl shapes and sizes.


Though the footprints of the plungers described above may take any number of shapes, for illustration purposes, FIG. 11 illustrates a top view of a plunger 500 according to another aspect. The plunger 500 includes an elongated handle 502 connected to a cup 506. The cup 506 may be comprised of a dome 506a integrally connected to a flat member 506b. The flat member 506b may have a footprint which widens at the rear corners (i.e., splays outward), and also at the front, along the outside edge of which has a more rigid material than other parts of the flat member 506b which are more pliant. This more pliant section flat member 506b may be of the same rubber/rubber-like material as the rest of the plunger cup, only thinner or, alternatively, may be made of a different material, such as silicon, or a silicon-like material which is fused/attached to the rubber cup section by the appropriate manufacturing method. According to one aspect, it will likely taper in thickness, so it is thinnest and most flexible at the outer edges.


Regardless of the embodiment, or combination of design elements from these embodiments, or other embodiments arrived at in the course of the continued testing and development of the prototype, the ideal design will accomplish:

    • 1. Improved efficiency when operating the plunger, due to increased suction by way of a semi-elliptical footprint creating a tighter seal over the toilet drain; and
    • 2. Decreased agitation of water around and above plunger footprint (less “splash back.”).


The combination of these improvements means such an improved plunger design is:

    • 1. Easier and more efficient to use (as compared to existing plungers, when using the same amount of force); and
    • 2. More hygienic to use (due to less splash back)


These improvements translate to an improved user experience by addressing/remedying the two common complaints of persons when using existing plungers, as previously outlined.


While the foregoing disclosure shows illustrative aspects, it should be noted that various changes and modifications could be made herein without departing from the scope of the disclosure as defined by the appended claims. The functions, steps and/or actions of the method claims in accordance with the aspects described herein need not be performed in any particular order. Furthermore, although elements of aspects disclosed herein may be described or claimed in the singular, the plural is contemplated unless limitation to the singular is explicitly stated.


Aspects described in connection with a given description, illustration, representation, or method may be substituted for aspects described in a different description, illustration, representation, or method.


The word “aspects” does not require that all aspects of the disclosure include the discussed tab, advantage, or mode of operation.


The word “coupled” is used herein to refer to the direct or indirect coupling between two objects. For example, if object A physically touches object B, and object B touches object C, then objects A and C may still be considered coupled to one another even if they do not directly physically touch each other.


The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the aspects described herein. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel aspects disclosed herein.


Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification.

Claims
  • 1. A plunger, comprising: an elongated handle having a first end and an opposing second end;a cup connected to the second end of the elongated handle, the cup comprising: a front-end portion having a generally elliptical shape; anda rear-end portion having a generally circular shape, where the front-end portion and the rear-end portion form a tear drop shape; anda flange integrally connected to the cup, where the flange is a continuous section extending downward from inside of the cup creating a tight seal against a vertical surface of a drain.
  • 2. The plunger of claim 1, wherein a top of the elongated handle has a T-shaped grip.
  • 3. The plunger of claim 1, wherein the flange further comprises: a front-end wall extending upwardly and outwardly into the front-end portion of the cup; anda back-end wall extending upwardly and outwardly into the rear-end portion of the cup; andwhere the front end-wall and the back-end wall are integrally connected forming a side wall of the flange.
  • 4. The plunger of claim 3, wherein the outwardly projecting front-wall end forms a recess allowing the cup to sit at or above a drain reducing an occurrence of water splashing back during use.
  • 5. The plunger of claim 1, wherein the flange has a circular shape.
  • 6. The plunger of claim 1, wherein the cup and the flange are made of an elastomeric material.
  • 7. The plunger of claim 6, wherein the elastomeric material is rubber.
  • 8. A plunger assembly comprising: a cover, the cover comprising: an elongated inner handle;a cup section integrally connected to the elongated inner handle;a plunger configured to be received within the cover, the plunger comprising:an elongated outer handle having a first end and an opposing second end;a cup connected to the second end of the elongated handle, the cup comprising: a dome; anda flat member integrally connected to the dome, the dome having an elliptical shape; anda flange integrally connected to, and extending downwardly from, the cup; andwherein the cover is configured to be placed over the plunger to protect the plunger; andwherein the elongated outer handle is configured to be received in the elongated inner handle; andwherein the cup section is configured to receive the cup of the plunger.
  • 9. The plunger assembly of claim 8, wherein the flange is located in a same vertical plane as the dome.
  • 10. The plunger assembly of claim 8, wherein the cup and the flange are made of an elastomeric material.
  • 11. The plunger assembly of claim 10, wherein the elastomeric material is rubber.
  • 12. A plunger comprising: an outer handle;an inner handle, the outer handle configured to slideably receive the inner handle;an upper membrane connected to the outer handle;a lower membrane connected to the upper membrane and the inner handle;where the inner handle moves vertically within the outer handle; andwhere moving the inner handle in an up and down motion actuates the lower membrane displacing liquid within a drain.
  • 13. The plunger of claim 12, wherein the outer handle is stationary.
  • 14. The plunger of claim 12, wherein the upper and lower membranes are made of rubber.
  • 15. The plunger of claim 12, wherein the upper and lower membranes are made of silicone.
  • 16. The plunger of claim 12, wherein the upper and lower membranes are made of a semi-flexible material.
  • 17. The plunger of claim 12, wherein the lower membrane is less rigid than the upper membrane.
Provisional Applications (1)
Number Date Country
63458386 Apr 2023 US