Vacuum-based cleaning apparatus and method

An apparatus and method for cleaning. The original motivation for the creation of the apparatus was the cleaning of shoes or bare feet, but the apparatus can be used in other organic and inorganic applications as well. The apparatus can be used in conjunction with a variety of different vacuum technologies, including wet dry vacuum systems. The apparatus can be implemented as a stand-alone mat or as modular component that can be combined with other units to achieve the desired coverage area.

BACKGROUND OF THE INVENTION

The invention relates generally to apparatuses and methods for cleaning. More specifically, the invention is an apparatus and method for cleaning that utilizes vacuum technology (collectively the “apparatus”).

According to the October 2010 issue ofMedicine&Science in Sports&Exercise, Americans take an average of 5,117 steps each day. Even though many Americans rely on motorized transport to take them to destinations for work, school, shopping, and recreation, the average American still walks more than 2 miles each day. The typical person takes approximately 2,000 steps per mile.

Any article of clothing gets dirty over time. However, footwear is particularly susceptible to becoming dirty because of the repeated contact to the ground and the outdoor environment. When walking outside, footwear is exposed to the elements such as snow, sand, water, dirt, mud, dust, slush, ice, and other substances (collectively “debris”).

The accumulation of debris on footwear is not just a matter of aesthetics. Debris can make it easy for the wearer of the footwear to slip and fall. Nor is the accumulation of footwear debris only a problem for the wearer of the footwear. Offices, retail stores, auditoriums, sports arenas, schools, industrial sites, and other settings are impacted by the accumulated footwear debris of their visitors. For example, the accumulated footwear debris brought into a shopping mall during the winter Christmas holiday season can be a significant aesthetic and safety issue for the mall. Footwear debris can also create problems relating to health, hygiene, and sanitation in places such as restaurants and hospitals.

The accumulation of debris on the foot is not limited to interior environments. For example, beach goers at an ocean side resort may bring unwanted sand from the beach into an exterior pool area, hotel, boat, restaurant, or automobile.

It retrospect, it would be desirable to provide people with a convenient and cost efficient technology capable of cleaning feet, footwear, and even other items capable of being encumbered with debris. In hindsight, it would also be desirable for such technology to utilize vacuum suction so that the person using the technology does not need to exert physical effort in removing debris from their person or possessions.

Unfortunately, the prior art teaches away from such approaches for a variety of reasons. The potential for user error and resulting safety issues deter against vacuum approaches in automated technologies. Such considerations are further complicated by the significant variety of different footwear and foot characteristics to be processed by a one-size-fits-all approach.

A small child will weigh significantly less than a large-framed obese adult male. The universe of women's shoes includes some very narrow heels that could conceivably get stuck in a vacuum-based cleaning device. Insufficient suction (or insufficient vacuum conditions) precludes effective cleaning. Conversely, sufficient suction power can cause problems if the geometry of the device or the cleaned item permits the cleaned item to become stuck in the device.

SUMMARY OF THE INVENTION

The invention relates generally to apparatuses and methods for cleaning. More specifically, the invention is an apparatus and method for cleaning that utilizes vacuum technology (collectively the “apparatus”).

The apparatus can be implemented using wet vacuum technology in conjunction with water as well as with dry vacuum technology.

The apparatus can be used to clean the shoes or even the bare feet of the person walking onto the apparatus. The apparatus can also potentially be used for items besides feet or footwear, including for example sports equipment, packages, and other items that can benefit from vacuum-based cleaning.

Vacuum conditions in the vacuum chamber of the apparatus can be maintained by a variety of tension-protrusion assemblies that include a tension component and a protrusion component. The tension component (which in many instances could also be called a compression component) partially counteracts the force of the mass placed on the apparatus, mass which can include that of a human being in many embodiments of the apparatus. The protrusion component in conjunction with a space in a top plate creates a gap that is small enough to sustain substantially vacuum conditions while large enough to permit the flow of air and in some embodiments, water.

The apparatus can be implemented as a stand-alone device or in a modular framework in which multiple units of the apparatus are connected in concert with each other. In some embodiments, the apparatus can be implemented in a highly embedded manner, such as being built into the floor in the entryway of a shopping mall or office building. The apparatus can also be implemented in highly mobile manner, allowing for consumers to store away the apparatus in a closet when the apparatus is not being used.

The apparatus can be more fully understood upon reading the accompanying drawings that are discussed briefly below.

The apparatus can be more fully understood upon reading the following detailed description.

DETAILED DESCRIPTION

The invention relates generally to apparatuses and methods for cleaning. More specifically, the invention is an apparatus and method for cleaning that utilizes vacuum technology (collectively the “apparatus”).

The apparatus can be implemented in wide variety of different configurations. In accordance with the provisions of the patent statutes, the principles and modes of operation of this invention have been explained and illustrated in preferred embodiments. However, it must be understood that this invention may be practiced otherwise than is specifically explained and illustrated without departing from its spirit or scope. For example, the apparatus can be implemented in a wide range of difference shapes and sizes, utilizing a wide range of different components. In many embodiments, the apparatus will be in the shape of a cube or a rectangular block, but other shapes are possible. The apparatus is readily scalable, and can be implemented in a modular manner. The apparatus can also be implemented in a fully mobile and portable configuration, as well as permanently embedded into a particular location.

The apparatus can be adapted in a variety of alternative embodiments to better address specific operating requirements in specific operating contexts.

FIGS. 1a-6rcollectively illustrate (1) different examples of a cleaning apparatuses100that utilizes vacuum technology and (2) different components and component configurations that can be utilized in such apparatuses100. The apparatus can include a variety of different components and component configurations.FIG. 1ais a perspective diagram illustrating an example of an embodiment of the apparatus100that is fully assembled.FIG. 1bis top view illustration of the apparatus100illustrated inFIG. 1a. InFIG. 1b, the operating environment of the apparatus100is also displayed. The apparatus100is embedded within a floor99instead of being place on the floor99.

The apparatus100can be used in conjunction with a wide variety of different vacuum cleaners. The requirements for suction power will necessarily be impacted by the size and intended context of the apparatus100.

As illustrated inFIGS. 1aand 1b, the apparatus100can include a vacuum adapter108(or simply an adapter108). The suction of the vacuum cleaner operates to the apparatus100through the adapter108. The purpose of the adapter108to connect the apparatus100to a vacuum cleaner (or some similar device that provides for generating suction force) that is otherwise separate and distinct from the apparatus100. Although the marketplace can provide a wide range of product options for vacuum cleaners, there are a relatively narrow range of connection geometries that are typically used in the vacuum cleaner industry. Moreover the adaptor108can utilize a variety of extensions or plugs to facilitate compatibility with a wide range of different vacuum cleaner configurations.

In most embodiments, it is advantageous to provide vacuum functionality to the apparatus100through the adapter108that is capable of being connected to various different vacuum devices rather than permanently building in the vacuum cleaner device into the apparatus100(or vice versa). A modular approach to the apparatus100that allows different components to be moved around can provide beneficial flexibility. An apparatus100permanently attached with an embedded vacuum cleaner is thus less desirable in most circumstances.

B. Core Functionality

The apparatus100uses vacuum technology, i.e. suction power, to facilitate the function of cleaning. The original inspiration behind the design of the apparatus100is the use of vacuum technology to clean shoes and feet, but at least some embodiments of the apparatus100can also be used outside of those contexts.

1. Loading the Apparatus

Use of the apparatus100involves loading the apparatus100, i.e. placing a mass on the top surface of the apparatus100. As illustrated inFIG. 1a, the apparatus100has a top plate104with a variety of protrusions106sticking up through the top plate104.FIG. 2aprovides a close up top view of a protrusion component106in the shape of a hemisphere protruding upwards through a circular opening110in the top plate104. Loading the apparatus100involves placing the load on one or more protrusions106, placing downward force on one or more protrusions106. For example, a human being wearing shoes steps onto the top plate104of the apparatus100, stepping on some of the protrusions106, resulting in the application of downward force on those protrusions106.

2. Compression of the Tension Component

As illustrated in the block diagram ofFIG. 2d, a protrusion component106is supported by a tension component112, which can also be referred to as a compression component112. The tension component112serves to allow the vertical motion of protrusion component106while at the same time acting to resist the magnitude of such motion. In many embodiments, the tension component112is some type of spring or an assembly that includes one or more springs.

The tension component112permits but also impedes the downward movement of the protrusion component106. The result of that slight downward motion is to open a slight gap in the top surface of the apparatus100.

3. Gap to Facilitate Cleaning

In stepping on the apparatus100, a slight gap is opened on the top surface of the apparatus100to permit sufficient air flow to facilitate cleaning. If the gap is too small, there is insufficient throughput for the debris being cleaned. If the gap is too large, then the suction power of the vacuum is negated, negatively impacting the ability of the apparatus100to perform the cleaning function of the apparatus100.

FIG. 2cillustrates an example of a protrusion component106in a fully unloaded state. The protrusion component106fits snuggly in the opening110in the top plate104. In contrast,FIG. 2billustrates the same components when the protrusion component106is loaded. As is illustrated inFIG. 2b, there is a small gap between the protrusion component106and the top plate104that does not exist inFIG. 2c. That gap must be the appropriate size to facilitate the throughput of debris while still maintaining near-vacuum conditions within the apparatus100itself.

BothFIGS. 2band 2creveal that it can be desirable to have a tapered opening110in the top plate104. The opening110is wider at the bottom of the top plate104than it is in the top of the top plate104.

C. Wet Vacuum and Dry Vacuum Embodiments

The apparatus100can be implemented to utilize wet vacuum technology in conjunction with the application of water to perform the cleaning function of the apparatus100. The apparatus100can also be implemented to utilize dry vacuum technology without the use of water to perform the cleaning function of the apparatus100.

The apparatus100can be implemented in a modular manner that allows the apparatus100to connect with other apparatuses100to provide a wider area of functionality.FIGS. 6band 6millustrate how multiple apparatuses100can function as a single unit in a highly modular approach.

As illustrated inFIGS. 1aand 1b, the apparatus100can also be implemented as a single stand-alone embodiment.

E. Portable and Embedded Embodiments

The apparatus100can be embodied in a highly portable device that consumers can take with them when they travel. The apparatus100can also be embodied in less mobile embodiments that can even involve embedding the apparatus100into specific locations as other types of fixtures are incorporated into living and office space.

The various components of the apparatus100can be comprised of a wide variety of different materials. In order to support the weight of human beings, many components such as the frame102, top plate104, and bottom plate114will often be comprised of a metal, such as aluminum. Other items such as the adapter108or protrusion components106can be comprised of plastic.

II. INTRODUCTION OF ELEMENTS AND DEFINITIONS

FIG. 1ais a perspective diagram illustrating an example of an apparatus100.FIG. 1bis a plan view diagram illustrating a top view of an apparatus100illustrated inFIG. 1a. In the example of the apparatus100illustrated inFIG. 1b, the apparatus100is embedded in a floor99.

A frame102of the apparatus100can serve a variety of purposes for the proper functioning of the apparatus100. The frame102can help implement the applicable vacuum-like conditions between a bottom plate114and a top plate104to support the functioning of the apparatus100. The frame102can also serve to keep various components of the apparatus100in the appropriate and desired positions.

The frame102is typically rectangular in shape, although it can be implemented in different shapes. The frame102also assists in sustaining near vacuum conditions between the top plate104and the bottom plate114. The frame102can be made of a wide variety of different materials. In most embodiments of the apparatus100, the frame102is stationary throughout the use of the apparatus100. A frame height116(seeFIG. 3a) exceeds a maximum top plate vertical position120(seeFIG. 3c) as well as the minimum top plate vertical position118(seeFIG. 3b).

B. Bottom Plate

FIG. 1aillustrates an example of a bottom plate114. The bottom plate114is not visible inFIG. 1bbecauseFIG. 1bis a top view of the apparatus100.

Examples of a bottom plate114are also illustrated inFIGS. 3a, 3b, 3c, 3d, 4a, 4b, 4c, 6a, 6b, 6n, and 6o. The bottom plate114forms the base of the apparatus100. In conjunction with the top plate104and the frame102, the bottom plate114helps sustain near vacuum conditions within the apparatus100. In most embodiments of the apparatus100, the bottom plate114is stationary through the use of the apparatus100. In many embodiments of the apparatus100, the bottom plate114is comprised of aluminum, although a wide variety of different materials and component configurations can be used.

C. Top Plate

In conjunction with the bottom plate114and the frame102, the top plate104helps sustain near vacuum conditions within the apparatus100. In many embodiments, the position of the top plate104is fixed, with one or more aspects of the tension-protrusion assembly moving in response to the load of the apparatus100. In a preferred embodiment, the position of the top plate104is fixed regardless of whether the apparatus100is loaded.

In other embodiments, the top plate104may be supported by a tension-protrusion assembly and move when the load on the apparatus100is changed. In such embodiments, the position of the top plate104will vary from a maximum vertical position120with respect to the bottom plate114, and a minimum vertical position118.

Something in the apparatus100will move when the apparatus100is loaded, so there will relative positions in the apparatus100that will be different when the apparatus100is loaded from when the apparatus100is not loaded.

In embodiments where the top plate104does not move, the distance between the top surface of the top plate104and the top of the protrusion component106changes when the magnitude of the load on the apparatus100changes.

In embodiments where the top plate104does move, the distance between the top surface of the top plate104and the bottom surface of the bottom plate114changes when the magnitude of the load on the apparatus100changes.

D. Openings/Holes in the Top Plate

One important attribute of the top plate104are the openings110in the top plate104that provide for the positioning of a protrusion component106upward through the top plate104.

Examples of openings110are disclosed inFIGS. 1c-1eand1g-1i. A number of openings110in the top plate104provide for maintaining a balance between (a) the absence of air and water flow between the area above the top plate104and the area below the top plate104; and (b) inadequate vacuum conditions for the effective cleaning of a connected vacuum cleaner. In a preferred embodiment, the openings110will be circular or some other type of elliptical shape, although alternative shapes are possible. The geometry of the openings110should be designed with the geometry of an applicable protrusion component106.

As discussed above, the core functionality of the apparatus100involves the loading of a tension-protrusion assembly133as illustrated by the block diagram inFIG. 2d, as well as in less abstract figures such asFIGS. 4a, 4b, 4c, 6f, 6i, 6l, 6n, and6o.

The apparatus100can utilize a wide variety of different tension-protrusion assemblies13to facilitate the proper vertical motion of the top plate104in response to the loading of the apparatus100(putting mass on the apparatus100) and the unloading of the apparatus100(removing mass from the apparatus100).

The tension-protrusion assembly can utilize a wide variety of different component parts, subassemblies, and configurations. Each tension-protrusion assembly will typically include a tension component112and a protrusion component106.

Examples of protrusion components106are illustrated inFIGS. 1a, 1b, 1c, 1d, and 1e. In many embodiments of the apparatus100, the protrusion component106will be positioned on top of the tension component112. A protrusion component106is the component in conjunction with the openings110that creates the geometry for enabling the proper air and water flow in the apparatus100. In many embodiments, the protrusion component is a half-sphere. Other geometric shapes can also be used.

Many embodiments of the protrusion components106will be hollow hemispheres132comprised of polyethylene and filled with silicon.

Examples of tension components112are illustrated inFIGS. 1f-1i. A wide variety of components are capable of serving as a tension component112, and thus a tension component112is illustrated by the “black box” inFIGS. 1f-1i. Common examples of tension components112are springs, but any device capable of contracting upon the loading of the apparatus100, and then expanding back upon the unloading of the apparatus100can potentially serve as a tension component112for the apparatus100.

In many embodiments, flat springs134coupled into pairs will be used to collectedly support four hemispheres132comprised of polyethylene and at least partially filled with silicon.

FIG. 3dillustrates an example of a mat121sitting on top of the top plate104. A mat121is an optional component of the apparatus100. In many embodiments, the mat121can be removed from the apparatus100by the user/owner of the apparatus100. The mat121serves the function of allowing the user to more easily remove excess debris from their feet, shoes, or other surface.

III. LOADING/UNLOADING OF THE TENSION-PROTRUSION ASSEMBLY

As discussed above, the tension-protrusion assembly133of the apparatus100is the part of the apparatus100that moves with the loading/unloading of the apparatus100. In most embodiments, the loading and loading of the apparatus100only involves the movement of components that comprise the tension-protrusion assembly133.

As illustrated by the block diagrams ofFIGS. 2d, 3a, 3b, 3c, and 3d, the tension-protrusion assembly133of the apparatus100can include a wide variety of different shapes and sizes of protrusion components106, tension components112, and component configurations.

As illustrated by the less abstract diagrams ofFIGS. 2a, 2b, 2c, 4a, 4b, and 4c, the tension-protrusion assembly133will often include a protrusion component106in the shape of a hemisphere and a spring122as the tension component112.FIG. 4cin particular displays a tension-protrusion assembly133that is attached to the bottom surface of the top plate104by a connector24that connects the top plate104to the spring122and with the protrusion component106being attached to the spring122.

IV. RELATIVE MOTION/DISTANCES WITHIN THE APPARATUS

As noted above, in many embodiments of the apparatus100, only the tension-protrusion assembly moves when the apparatus100is loaded/unloaded. It can be useful to identify certain distances and how such distances vary between a loaded and unloaded state.

A. Distance Across the Opening

As illustrated inFIGS. 2band 2c, the distance across the openings110in the top plate don't change with the loading/unloading of the apparatus100, but the opening can become progressively larger as the opening110progresses downwards from the top surface of the top plate104.

B. Height of the Frame

As illustrated inFIG. 3a, the frame102is typically the highest point of the apparatus100. At a minimum, the frame height116must be at least as tall as the top surface of the top plate104.

C. Distance Between the Top and Bottom Plates

The vertical area between the top plate104and bottom plate114as surrounded by the frame102makes up what is an air tight chamber to facilitate the suction of debris through the apparatus100to the vacuum cleaner. In most embodiments the top plate104does not move with the loading/unloading of the apparatus100, and as such a top plate/bottom plate distance118(as illustrated inFIG. 3b) is constant regardless of the operating state of the apparatus100.

D. Distance Between Protrusion and Bottom Plate

InFIGS. 3cand 4b, element120is the distance between the uppermost portion of the protrusion component108and the plane of the bottom surface of the bottom plate114when the apparatus100is not loaded.

InFIGS. 3dand 4a, element121is the distance between the uppermost portion of the protrusion component108and the plane of the bottom surface of the bottom plate114when the apparatus100is loaded.

The different between distance120and distance121will vary in different embodiments of the apparatus100. In many embodiments, that differential will be approximately 0.5 inches.

V. PROCESS FLOW VIEWS

As discussed above, the apparatus100can be implemented in both wet and dry embodiments.

FIG. 5aillustrates an example of a process for using the apparatus100that utilizes water in conjunction with vacuum suction to clean the load places in the apparatus100.

At200, the user steps onto the top plate104of the apparatus100.

At202, the vacuum is activated.

At204, water is supplied to the area being cleaned.

At206, the water is deactivated.

At208, the vacuum suction is deactivated.

Then the process ends.

FIG. 5billustrates an example of a process for using the apparatus100that does not utilize water in conjunction with vacuum suction to clean the load places in the apparatus100.

At200, the user steps onto the top plate104of the apparatus100.

At202, the vacuum is activated.

At208, the vacuum suction is deactivated.

Then the process ends.

VI. DETAILED DESCRIPTION OF VARIOUS COMPONENTS AND CONFIGURATIONS

FIG. 1ais a perspective view diagram illustrating an example of a top view of an apparatus100. The apparatus100includes a frame102, a top plate104, a variety of protrusion components106shaped as hemispheres132, a vacuum adapter108, and a bottom plate114.FIG. 1bis a plan view diagram illustrating an example of a top view of the apparatus100displayed inFIG. 1a.

FIG. 2ais a plan view diagram illustrating an example of “close-up” top view of a portion of the illustration ofFIG. 1bin which a protrusion component106in the shape of a hemisphere sticks out of an opening100in a top plate104.

FIG. 2bis a plan view diagram illustrating an example of a cross-section side view that corresponds toFIG. 2awhen the apparatus is in a loaded operating state.FIG. 2cis a similar diagram, except that it relates to the apparatus100in an unloaded operating state.

FIG. 3ais a plan view diagram illustrating an example of a cross section side view of the apparatus100and the positioning of different components hidden from view by the frame102.FIG. 3billustrates the same configuration asFIG. 3a, except that the frame102is removed from view.FIGS. 3aand 3bpertain to a loaded state whileFIGS. 3cand 3dpertain to an apparatus100in an unloaded state.

FIG. 4ais a plan view diagram illustrating an example of a cross section side view of three tension-protrusion assemblies133in a state of maximum compression within the apparatus100.FIG. 4brelates to the same components asFIG. 4a, except that the apparatus100is an unloaded state.FIG. 4cis a close up view of a single tension-protrusion assembly fromFIG. 4b.

FIG. 6ais a perspective diagram illustrating an example of a bottom plate114and frame102comprised of U-brackets126. The U-brackets126are comprised of aluminum, and are 14⅝″ long, ⅛″ thick, and ¾″ wide with 45 degree cuts at the ends. The bottom plate114is also comprised of aluminum, that is 14⅝″ wide, 20⅝″ long, and 1/16″ thick. The height of the partial frame102illustrated inFIG. 1ais approximately ¾″ high.

FIG. 6bis a perspective diagram illustrating an example of a bottom plate114, frame102, and an adaptor108. In addition to the components illustrated inFIG. 6a, a vacuum hose adapter108approximately 1¼″ in diameter is also disclosed. The adaptor108includes male mating component130to connect with female mating components129in the U-brackets126of the frame102.

FIG. 6cis a perspective diagram illustrating an example of a top surface of a top plate104with circular openings110. The top plate102is comprised of aluminum; with dimensions correspond to those of the bottom plate114. There are 48 tapered openings110measuring 1⅜″ on the top side and 1½″ on the bottom side. The top plate104includes a border that is wider than the rest of the top plate104.

FIG. 6dis a perspective diagram illustrating examples of L brackets127and U brackets128that can used to comprise the frame102. The U brackets128are used in modular embodiments of the apparatus100to cover the space between the various modules when connected together. The L brackets127are 12⅝″ long, ½″ wide, and 1/16″ thick. They have 45 degree angle cuts added to the ends.

FIG. 6eis a plan view diagram illustrating an example of a top view of a flat spring134. The flat spring134illustrated inFIG. 6eis ¾″ wide and 5″ long. The flat spring134includes 3 holes136, with a 3/16″ center hole for mounting the spring134to the top plate104and the two other ⅛″ holes for mounting the hemispheres132(i.e. protrusion components106) to the spring134.FIG. 6fis a plan view diagram illustrating an example of a cross section side view of a tension-protrusion assembly133that includes a hemisphere132with the dimensions of 1.5″×7.5″, that is hollow with a wall thickness of ⅛″. The assembly133also includes a screw142, a small washer144, a wooden donut138, a large washer146and a hex nut148. The spring134has thickness of 0.025″ and is comprised of blue tempered shim stock. The wooden donut138has a 1¼″ diameter, is ¼″ thick, and has a center hole that is ¼″ in diameter.FIG. 6gis a plan view diagram illustrating an example of a top view of hemisphere132.FIG. 6his a plan view diagram illustrating an example of a top view of a donut138used within the tension-protrusion assembly133

FIG. 6iis a plan view diagram illustrating an example of a cross section side view of a tension-protrusion assembly134that does not include a connector on the top surface of the hemisphere132. InFIG. 6i, the bolt142goes upward through the bottom of the hemisphere132rather than downwards from the top surface of the hemisphere132.

FIG. 6jis a perspective view diagram illustrating an example of a top view of top plate104(as illustrated inFIG. 6c) and various L joints comprising the upper portion of the frame102that corresponds to the top plate104(in contrast to the bottom portion which corresponds to the bottom plate114).

FIG. 6kis a perspective view diagram illustrating an example of a bottom view of a top plate104and a configuration of tension-protrusion assemblies134attached to the bottom surface of the top plate104. As illustrated in the Figure, the tension-protrusion assemblies134are attached to the bottom surface of the top plate104, not the top surface of the bottom plate114. A spill barrier150is approximately ½″ high. The apparatus100also includes an alignment peg152to facilitate peg location for modular embodiments of the apparatus100. The tension-protrusion assemblies133are each comprised of two flat springs134and four hemispheres132.

FIG. 6lis a plan view diagram illustrating an example of a cross section side view of a tension-protrusion assembly133that includes two hemispheres132attached to a single flat spring134. A bolt142is used to connect the hemispheres132to the flat spring132in a configuration that includes two washers144and146.

FIG. 6mis a perspective view diagram illustrating an example of how the apparatus100can be implemented in a modular manner. A mating connector160comprised of male mating connections140is used to connect the apparatus100to other apparatuses100or to an adapter108.FIG. 6malso discloses an adapter attachment162, with different attachments162being configured to interface with different vacuum devices.

FIG. 6nis a plan view diagram illustrating an example of a cross section side view of a tension-protrusion assembly133and its position with respect to a bottom plate114in an unloaded state.FIG. 6ois the same assembly133, where one hemisphere132is loaded. The distance120that the hemisphere132protrudes upwards approximately ⅜″. The distance118between the plates is ¾″. A captive nut166is used to adjust flat spring134tension. Screws164protruding from the bottom of the hemispheres132serve as a contact point of maximum movement of the hemispheres132, with that distance162being equal to the distance between the bottom plate114to screw164.FIG. 6oalso illustrates an example of gaps168created by the depression of the hemispheres132,

FIG. 6pis a plan view diagram illustrating an example of a bottom view of a hemisphere132an aluminum hex insert170.

FIG. 6qis a plan view diagram illustrating an example of a cross section side view of a hemisphere132with an aluminum hex insert170.

FIG. 6ris a perspective view diagram illustrating an example of a bottom perspective view of a hemisphere132with an aluminum hex insert170.

In accordance with the provisions of the patent statutes, the principles and modes of operation of this invention have been explained and illustrated in preferred embodiments. However, it must be understood that this invention may be practiced otherwise than is specifically explained and illustrated without departing from its spirit or scope.