Patent Application
20080045123
Various embodiments of the present invention will now be discussed with reference to the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope.
The present invention relates to sanding systems for use in sanding floors and any other desired structure or surface. The sanding systems include a sander and a dust collection system that employs the use of wet/dry vacuum systems in removing dust generated by the sanding process. The dust collection system includes means for injecting a liquid into the suctioned dust to help in removing and compacting the dust, and means for then removing the liquid from the dust mixture. By mixing a liquid with the dust and then removing the liquid, the moist dust is more compacted than with conventional sanding systems. The moist dust also tends to clump together and not spill out of the vacuum when emptying the vacuum system. Finally, by adding moisture to the dust the potential for fire hazard is greatly reduced.
Depicted in
Floor sander 9 includes a motorized sanding unit 90 with an elongated handle 92 extending therefrom. Sanding unit 90 includes an electrically operated motor 91 that controls a sanding medium 93. Sanding medium 93 is the component that contacts the wood floor to cause the floor to be sanded. Many types of sanding medium 93 can be used. For example sanding medium 93 can comprise a roughened belt, a drum, a disk or any other type of sanding medium known in the art. Motor 91 is configured to cause sanding medium 93 to move in a manner that sanding of the wood floor occurs as a result. For example, motor 91 can cause sanding medium 93 to vibrate or rotate (e.g., if sanding medium 93 is a disk), or provide looping motion (e.g., if sanding medium 93 is a belt). Other types of motion can alternatively be provided, as is known in the art.
A shroud 160 surrounds sanding medium 93 and forms a chamber 162. Shroud 160 is used to confine the dust that is generated by the sanding process so the dust can be collected by the system. Shroud 160 can be made of plastic, metal, or other material known in the art. A tube 164 extends from shroud 160, the tube 164 communicating with chamber 162 of shroud 160 at a first end 166 of tube 164. The second end 168 of tube 164 contains a coupling 170 that forms an outlet port 94. Alternatively, coupling 170 (and therefore outlet port 94) can be formed directly on shroud 160 and tube 164 can be eliminated. Coupling 170 and outlet port 94 are configured such that when first end 96 of vacuum hose 11 is attached thereto, open fluid communication is established between vacuum hose 11, coupling 170, and chamber 162 of shroud 160. In the depicted embodiment, coupling 170 is a standard coupling known in the art for receiving a commercially available dust collection system vacuum hose.
Sanding unit 90 is typically mounted on wheels 172 to allow for easy movement of floor sander 9. The foregoing discussion regarding sanding unit 90 is exemplary only. Virtually any commercially available floor sanding units that can accept a vacuum hose for dust collection can be used. For example, American 8 Drum Sander by Clarke American Sanders can be used. It is also appreciated that stationary sanders, hand sanders, commercial sanders, and other types of sanders can also be used in association with the present invention.
Vacuum hose 11 comprises a flexible hose that extends between a first end 96 and a spaced apart second end 98. First end 96 is configured to selectively couple with coupling 170 on floor sander 9 so as to communicate with chamber 162 of shroud 160. In one embodiment a first coupling 97 is included at first end 96 to aid in coupling to floor sander 9. In other embodiments, first end 96 couples to floor sander 9 directly without using a first coupling 97. As detailed below, second end 98 of vacuum hose 11 is configured to selectively couple with a hose coupling 31 or a transfer conduit 28 of vacuum system 10. In one embodiment, second end 98 of vacuum hose 11 includes a second coupling 99 for selectively coupling to vacuum system 10. In other embodiments, second end 98 selectively couples to vacuum system 10 without using second coupling 99. In one embodiment of the current invention, flexible vacuum hose 11 is a conventional vacuum hose currently used with commercially available vacuums, dust collection systems or the like.
Vacuum system 10 includes a canister 12 having a top section 14, a bottom section 16, and two middle sections 18 disposed therebetween. Sections 14, 16, and 18 are removable coupled together using conventional clamping members 19. In one embodiment, sections 14, 16, and 18 are coupled together so as to produce a liquid tight seal therebetween. In some embodiments vacuum system 10 has only have one middle section 18. In some embodiments canister 12 is mounted on a portable cart 13 having wheels 15 on which vacuum system 10 is rolled around during set-up and use.
Depicted in
Coupled with chamber 26 through inlet port 20 is transfer conduit 28. As depicted in
Depicted in
Means are provided for coupling a fluid line to the vacuum hose or the transfer conduit so that a liquid can be delivered thereto. By way of example and not by limitation, depicted in
In one embodiment of the present invention, means are provided for producing a relative vacuum or relative negative pressure within chamber 26 such that dry matter and liquid can be drawn into chamber 26 through transfer conduit 28. By way of example and not by limitation, depicted in
A cyclonic separator 40 is attached to the opposing side of vacuum motor 36. In the embodiment depicted, separator 40 has a frustaconical configuration and includes a constricted upper end 42 coupled with vacuum motor 36 and a radially outwardly flared lower end 44. In alternative embodiments, the exterior of separator 40 need not be frustaconical, but preferably has a lower end having a diameter greater than the diameter of the upper end. Lower end 44 is freely disposed within chamber 26 and bounds an opening 46. Separator 40 has an interior surface 48 that bounds a passageway 50 extending from opening 46 to vacuum motor 36. Separator 40 is disposed such that mixing tube 37 of transfer conduit 28 is disposed above lower end 44 of separator 40. Transversely extending across passageway 50 is a filter 52. In one embodiment, filter 52 comprises a plastic mesh screen having a pore diameter in a range between about 0.1 inches to about 0.5 inches with about 0.1 inches to about 0.3 inches being more common. Other pore sizes can also be used.
Also disposed within chamber 26 is a frustaconical collecting cone 54. Collecting cone 54 includes a radially enlarged upper end 56 that is secured to interior surface 24 of canister 12. Collecting cone 54 also includes a constricted lower end 58. An interior surface 60 bounds a passageway 62 extending between ends 56 and 58. Collecting cone 54 is concentrically disposed below separator 40 with a gap 63 formed therebetween. Secured to lower end 58 of collecting cone 54 is an enlarged filter apparatus 64. Filter apparatus 64 is removably secured to collecting cone 54 using conventional means for connecting such as hooks, snaps, ties, Velcro®, clamps, or the like. Filter apparatus 64 is configured to allow liquids to pass therethrough but to retain dust and other particles therein. In one embodiment, filter apparatus 64 is a filter bag made from mesh netting. In one embodiment, filter apparatus 64 is a rigid basket with a metal mesh attached thereto. Other types of filtering apparatuses can also be used. In an alternative embodiment, collecting cone 54 can be removed and filter apparatus 64 can be configured to removably attach directly to interior surface 24 of canister 12. In one embodiment, filter apparatus 64 has a pore diameter in a range between about 0.0357 inches to about 0.006 inches with about 0.03125 inches to about 0.012 inches being more common. Other pore sizes can also be used. In one embodiment, filter apparatus 64 has a capacity in a range between about 4.5 gallons to about 5.5 gallons with about 4 gallons to about 6 gallons being more common. Other capacities can also be used.
Disposed below filter apparatus 64 is a support member 100. Support member 100 is configured to help support or fully support the weight of filter apparatus 64 when compacted dust becomes collected therein. Support member 100 also helps to prevent rupturing of filter apparatus 64. Support member 100 is secured to interior surface 24 of canister 12 using conventional means for connecting, such as welding, clamps, fasteners, or other methods. Alternatively, support member 100 can be self-standing on the floor of canister 12. In some embodiments, support member 100 is removable. Support member 100 can be configured to allow liquids to pass therethrough or therearound. Support member 100 can be made of a variety of different materials and can have a variety of different configurations. By way of example and not by limitation, support member 100 can comprise a screen, grate, mesh, fabric, filter material, plate with holes extending therethrough, wires or bars extending across chamber 26, or any other structure that can support filter apparatus 64 and still allow liquid that passes through filter apparatus 64 to travel down to the bottom of chamber 26. One specific example of support member 100 comprises a 1 inch×1 inch×0.08 inch wire mesh grill.
In one embodiment, a porous basket 101 is disposed on support member 100 below filter apparatus 64. Basket 101 has a floor with upstanding sides which form a bucket-like or bowl-like interior to constrain the bottom end of filter apparatus 64. Basket 101 has a a plurality of holes extending therethrough to allow liquids to pass through basket 101. Various types of structures can be used as basket 101. By way of example and not by limitation, basket 101 can comprise a bowl, a basket, a bucket, or any bowl-like container with holes extending therethrough or made with wires or bars, or any other structure that can constrain filter apparatus 64 and still allow liquid that passes through filter apparatus 64 to travel down to the bottom of chamber 26. As depicted, the bottom end of filter apparatus 64 is placed within basket 101. The height of basket 101 can be a few inches or the entire height of filter apparatus 64, or anywhere in between. Basket 101 can be free standing on support member 100 or removably attached to support member 100 using conventional means for attaching, such as clamps, fasteners, or other methods. Alternatively, basket 101 can be permanently attached to support member 100 to, along with support member 100, help support filter apparatus 64 as it fills up.
In one embodiment of the present invention means are provided for removing waste liquid collected within bottom end 29 of chamber 26 through fluid outlet port 23 when the waste liquid rises above a certain level. By way of example and not by limitation, depicted in
As previously mentioned, drain line 66 functions to discharge the waste liquid collected within bottom end 29 of chamber 26. In one embodiment, a conventional hose bib 106 is attached to drain line 66. This allows a conventional flexible drain hose 108 (
When vacuum motor 36 is turned on, a relative vacuum is produced within chamber 26. This relative vacuum produces a suction which is used to draw air, dry matter (including sanding dust), and/or liquid into chamber 24 through transfer conduit 28. Because of the orientation of mixing tube 37, the air and other matter enters chamber 26 at an orientation substantially tangential with interior surface 24 of canister 12. As a result, a substantially cyclonic flow is created within chamber 24 wherein the air and other matter swirls in a circular and downward path within chamber 24. As the circling air moves downward, the space between the exterior surface of separator 40 and interior surface 24 of canister 12 decreases. As this space decreases, the speed of the air traveling within this space increases. The centrifugal force created by the increased air speed causes the liquid and particulate suspended within the air to move outward towards interior surface 24 of canister 12. As the air and other matter passes below lower end 44 of separator 40, the relatively clean air passes through gap 63 where it is drawn up into passageway 50, through motor 26, and out vent line 38. Filter 52 functions to catch any additional material that is accidentally drawn in with the air.
The liquid and particulate continue under gravitational force to travel down into passageway 60 of collecting cone 54 and into filter apparatus 64. The particulate and dust are retained and compressed within filter apparatus 64. The liquid and smaller particles suspended therein passes through filter apparatus 64 and are collected at bottom end 29 of chamber 26.
In one embodiment, vacuum system 10 can be designed such that when vacuum hose 11 is coupled with vacuum port 34, vacuum motor 36 can be automatically turned on. Likewise, vacuum motor 36 is automatically turned off when hose 11 is removed from vacuum port 34. In alternative embodiments, vacuum motor 36 can be turned on and off manually by using a switch located on or adjacent to vacuum port 34 or any other portion of canister 12 or a switch located on floor sander 9. Various types of switches can be used. For example, toggle switches, push buttons, dials or other types of switches known in the art can be used. Alternatively, vacuum motor 36 can be turned on and off automatically when floor sander motor 90 is turned on and off, respectively.
To prevent over filling chamber 26 with liquid, the present invention also includes means for automatically turning on the means for removing waste liquid when the waste liquid within chamber 26 rises to a predetermined upper level and for automatically turning off the means for removing waste liquid when the waste liquid within chamber 26 drops to a predetermined lower level. By way of example and not by limitation, depicted in
Float switch 68 is in electrical communication with pump 102. In one embodiment float switch 68 is attached directly to pump 102 so that float switch 68 rotates upward as waste liquid fills chamber 26 and rotates downward as waste liquid exits chamber 26. Alternatively, a tie, such as a clamp or other structure, can be used to secure float switch 68 to canister 12 at a short distance from float switch 68. The tie functions to tether float switch 68 so that float switch 68 rotates upward and downward about the tie.
Accordingly, as liquid collects and rises within the bottom of chamber 24, float switch 68 rotates upward about pump 102. When float switch 68 is rotated upward to a predetermined angle based on the elevation of the waste liquid, float switch 68 automatically moves to a first activation state which turns pump 102 on. This causes pump 102 to remove the waste liquid from the bottom end 29 of chamber 26 and expel the liquid through drain line 66. As liquid drains from chamber 26, float switch 68 rotates downward about pump 102. When float switch 68 is rotated downward to a predetermined angle based on the elevation of the water, float switch 68 automatically moves to a second activation state which turns pump 102 off, thereby stopping the removal of waste water from chamber 26. As noted above, this process continues independent of whether vacuum motor 36 is turned on or off By selectively adjusting the distance between pump 120 and float switch 68, the level of the waste liquid at which float switch 68 moves between the activation states can be controlled.
The present invention also envisions a variety of alternative embodiments for the means for turning the means for removing waste liquid on and off. By way of example, float switch 68 can be replaced with sensors vertically spaced apart within chamber 26. When the waste liquid rises to the upper sensor, pump 102 is turned on. When the waste liquid drops below the lower sensor, pump 102 is turned off. As another example, a sliding switch can be attached to the wall of chamber 26 with a float ball attached. As with the previous example, when the waste liquid rises to the upper sensor, pump 102 is turned on. When the waste liquid drops below the lower sensor, pump 102 is turned off.
Returning to
Valve 88, such as a manual valve or an electronically operated solenoid valve, can be coupled with fluid line 80 to control the flow of water into transfer conduit 28. In one embodiment, valve 88 is electrically coupled with vacuum motor 36 such that when vacuum motor 36 is turned on, valve 88 is opened allowing water to be dispensed or injected into transfer conduit 28. If valve 88 is used, second end 86 of fluid line 80 can alternatively be attached directly to valve 88 or valve 88 can have hose bib 118 for removable attachment of a conventional hose if fluid line 80 comprises a hose, as described above. In an alternative embodiment valve 88 can be eliminated.
In one embodiment a nozzle 89 (see
As noted above, canister 12 can be mounted on a portable cart 13. Cart 13 can comprise a base 72 having a top surface 73 on which bottom section 16 of canister 12 is mounted. Mounting can be by any conventional means, including but not limited to welding, screws, bolts, frictional engagement, and the like. Projecting down from a bottom surface 74 of base 72 are a plurality of wheels 75, which allow vacuum system 10 to be portable. Wheels 75 are typically attached to base 72 on or close to an outer edge 76 of the bottom surface 74 of base 72 to provide a large wheel base to prevent tipping of the canister. Wheels 75 can come in a variety of different sizes and shapes. Extending up from top surface 73 of base 72 at the outer edge 76 is a lip 78. Lip 78 is used to help keep canister 12 in position and prevent canister 12 from slipping off of base 72. Lip 78 can completely surround top surface 73 of base 72, or can be divided into many spaced apart lips.
It is appreciated that cart 13 can come in a variety of different sizes, shapes, and configurations that equally function to enable easy transport of vacuum system 10. For example, depicted in
Referring to
The operator then turns on wood floor sander 9 and begins sanding, generating dust with the sanding action. As a result of the relative vacuum created by vacuum motor 36 within chamber 26 and vacuum hose 11, dust that is produced by floor sander 9 is suctioned into vacuum system 10 through vacuum hose 11, thereby creating a dust stream.
As the water, air, and dust stream enter transfer conduit 28 and travel along mixing tube 37, the water mixes with the surrounding air so that the dust and other particles become suspended within the water, thereby creating a liquid/dust mixture. Once the liquid/dust mixture enters chamber 26, as previously discussed, the water and suspended particles are driven outward against interior surface 24 of canister 12 and downward toward bottom end 29 of chamber 26. Because the dust is now within a liquid/dust mixture, the weight of the mixture improves the flow of the dust downward. As the liquid/dust mixture falls downward, it is directed by collecting cone 54 into filter apparatus 64.
As the liquid/dust mixture presses against filter apparatus 64, most of the water within the liquid/dust mixture separates from the mixture and passes through filter apparatus 64. The remaining portion of the mixture, including most of the dust, is prevented from passing through filter apparatus 64 and thus is retained therein. As a result, the waste liquid collects in the bottom of chamber 26 while the dust is compacted within filter apparatus 64. Support member 100 supports the weight of filter apparatus 64 as filter apparatus 64 fills up with compacted moistened dust. It is noted that the water from fluid line 80 not only helps to collect and remove dust and other particulate from the air, it also functions to help wash the particulate matter down the length of chamber 26 to bottom end 29 and to compact the collected dust.
Basket 101, if used, also helps in supporting the structure of filter apparatus 64 as filter apparatus 64 fills up. Filter apparatus 64 can become very heavy when full of wet dust and difficult to handle if filter apparatus 64 is a non-rigid apparatus, such as a mesh bag. If basket 101 is unattached to or detachable from support structure 100, basket 101 can be removed with filter apparatus 64 disposed within basket 101. The rigid structure of basket 101 supports filter apparatus 64 during removal, thus making removal of filter apparatus 64 much easier.
As waste liquids collects in the bottom of chamber 26, float switch 68 rotates up to the first activation state, as discussed above, thereby turning on pump 102. The collected waste liquid is subsequently pumped out through drain line 66 until float switch 68 rotates downward to the second activation state. At that point, the pump turns off and waste liquid begins collecting again in the bottom of chamber 26. This cycle continues until the system is turned off. As noted above, the removal of waste liquid can occur independent of the vacuuming action. Thus, sanding can be done continuously without worry of vacuum motor 36 stopping while the liquid is being removed from canister 12. Filter apparatus 64 is periodically emptied or replaced by the operator as needed.
It is appreciated that some of the above steps may be altered or omitted depending on the options available. For example, if vacuum system 10 automatically turns on when sander 9 turns on, then the step of manually turning vacuum motor 36 on can be omitted. It is also appreciated that while the current method has been described using an exemplary wood floor sanding system, the methods of containing dust produced by sanding described above can also be used for other types of sanding systems, such as shop sanding (wood and metal). The methods described above can also be used in non-sanding systems which also produce dust, such as wood sawing systems or the like. Examples of saws that can be used with the present invention include radial arm saws, table saws, various commercial saws, and the like. In these embodiments, the vacuum hose is connected to the saw or adjacent to the saw where the saw dust is generated or collected. In view of the foregoing, the inventive vacuum system 10 can be used in association with any number dust generated machines such as saws, sanders, and the like.
Although the following flow rates and dimensions can vary based on the size and number of vacuum motors used, in one embodiment, mixing tube 37 typically has a diameter in a range between about 1.5 inches to about 2.5 inches. The length of mixing tube 37, i.e., the distance between where fluid line 80 intersects transfer conduit 28 and terminus 41, is typically in a range between about 11 inches to about 5 inches. The flow rate of water entering mixing tube 37 through fluid line 80 is typically in a range between about 0.15 gallons/minute to about 0.35 gallons/minute. Other dimensions and flow rates can also be used. The present invention also envisions that mixing tube 37 can be fully positioned within chamber 26, fully positioned outside canister 12, or can extend both inside and outside of chamber 26.
Depicted in
Vacuum system 122 is also distinguished over vacuum system 10 in that a preliminary collecting cone 136 is disposed between collecting cone 54 and separator 40. The use of second canister 124 and vacuum motors 126 and/or 128 are alternative embodiment to the means for vacuuming as previously discussed.
Depicted in
As mentioned previously, although the discussion set forth herein has been directed toward a wood floor sander, it is appreciated that the portable wet/dry vacuum system according to various embodiments of the current invention can also be used to remove dust generated by other types of sanding known in the art, such as shop sanding, metal sanding, and the like. The portable wet/dry vacuum system can also be used for cutting systems that produce dust.
As noted in the discussion above, the sander system and methods described herein provide a number of unique benefits over current wood sanding systems. For example, by adding fluid into the incoming dust, the dust is more compacted and tends to clump together. This leads to smaller systems and/or the canister needing to be emptied less often. Filters also last longer and require less cleaning. Additionally, because the dust tends to clump together, the dust does not spill out of the canister when the canister is emptied. Also, the fire hazard encountered with dry dust systems is virtually eliminated
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
