INVENTORS: Christopher Wayne Smith

Sterling Elliot Nesbit

APPLICANT: Harris Research, Inc.

TECHNICAL FIELD

[0001] The disclosure relates to cleaning machines for carpeted surfaces, and more particularly to an extractor head for a vacuum cleaner, carpet-cleaning machine, or floor wand tool for use in cleaning a carpeted surface.

BACKGROUND ART

[0002] A vacuum extraction head, such as those on a rotary vacuum cleaner, carpet-cleaning machine, or floor wand tool for use with such a cleaner or machine, is used for extraction of liquids and cleaning solution from fabric typically have one or more rotary heads with an extractor head attached to the bottom of the rotary head. The extractor head is connected to a vacuum suction and glides over the carpeted surface. Cleanings spray jets that precede the extractor head in the path of the machine discharge cleaning solution and fluids onto the carpet surface. The extractor head then passes over the surface and sucks the cleaning fluid, water, dirt, or other materials from the surface of the carpet into the vacuum pathway.

[0003] A primary concern of any vacuum extractor head is efficiency of extraction.

A more efficient extractor head permits additional cleaning liquid and other liquids or solids to be removed from the carpet in an efficient and effective manner. SUMMARY OF INVENTION

[0004] In some instances, the invention concerns a cleaning machine extractor head configured to withdraw fluid from a carpeted surface, the extractor head having an elongated base plate configured to be movably disposed on the carpeted surface, and having a tapering cross section with a flat wide upper surface and a narrow lower surface; and a plurality of apertures extending from the upper surface to the lower surface, wherein each aperture is beveled at the lower surface.

[0005] In other instances the invention concerns a cleaning machine extractor head configured to withdraw fluid from a carpeted surface, the extractor head having an elongated base plate configured to be movably disposed on the carpeted surface, and having a tapering cross section with a wide upper surface having a trough and a narrow lower surface; and a plurality of apertures extending from the upper surface to the lower surface, wherein each aperture is beveled at the lower surface.

[0006] The invention is directed to other aspects as may be determined from the detailed description below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figures 1A and IB depict a known extractor head.

[0008] Figures 2A and 2B depict a first embodiment of a new extractor head according to this disclosure.

[0009] Figures 3A and 3B depict a second embodiment of a new extractor head according to this disclosure.

[0010] Figures 4A and 4B depict a third embodiment of a new extractor head according this to disclosure. [0011] Figures 5A and 5B depict a fourth embodiment of a new extractor head according to this disclosure.

[0012] Figures 6A and 6B depict a fifth embodiment of a new extractor head according to this disclosure.

[0013] Figures 7A and 7B depict a sixth embodiment of a new extractor head according to this disclosure.

[0014] Figures 8A and 8B depict a seventh embodiment of a new extractor head according to this disclosure.

[0015] Figures 9A and 9B depict an eighth embodiment of a new extractor head according to this disclosure.

[0016] Figures 10A and 10B depict a ninth embodiment of a new extractor head according to this disclosure.

[0017] Figures 11A and 11B depict a tenth embodiment of a new extractor head according to this disclosure.

[0018] Figures 12A and 12B depict an eleventh embodiment of a new extractor head according to this disclosure.

[0019] Figures 13A and 13B depict a twelfth embodiment of a new extractor head according to this disclosure.

[0020] Figures 14A and 14B depict a thirteenth embodiment of a new extractor head according to this disclosure.

DESCRIPTION OF THE EMBODIMENTS

[0021] Figure 1 depicts a prior art cleaning machine extractor head device 10 for removing liquid from fabric, such as carpet, as described in US Patent No. 6,266,892. The vacuum head device 10 withdraws a fluid from a carpeted surface. Such a device 10 may be attached to a carpet cleaning machine, either upon the manufacture of the machine or afterwards attached to a machine. Briefly, the device 10 includes a base plate 18 with one or more apertures 22 which serve as extraction nozzles to remove liquid from the fabric or carpet surface. The base plate 18 preferably is elongated and movable on or through the carpeted surface. The one or more apertures 22 are formed in the base plate 18 and withdraw fluid under a vacuum force supplied by the machine, as is well known in the art. The base plate 18 may have a tapering cross section with a wider upper surface 26 and a narrower lower surface 30.

[0022] The cross section of the base plate 18 may be V-shaped, with an angled forward surface 32 that creates a narrow lower surface 30. The narrow lower surface 30 advantageously is better able to penetrate into the carpeted surface, and thus locate the apertures 22 closer to the bottom of the carpeted surface, and the fluid. The lower surface 30 can be rounded to facilitate movement through the carpet. The apertures 22 are formed in an array along the length of the base plate 18. The array of apertures 22 can be linearly aligned, as shown. The base plate 18 has a lower surface 30 with a defined width.

[0023] On the upper surface 26 of the base plate 18 is located a projection 40 that surrounds the apertures 22. Only this projection 40 is inserted into the wand or other nozzle of the vacuum system. A gasket that is well known in the art is placed around the projection 40 to form a seal when the device is attached to the wand or other nozzle. The projection 40 prevents the gasket from inadvertently obstructing any aperture 22. [0024] On the lower surface 30 of the base plate 18, the apertures 22 can be countersunk to minimize the risk of snagging carpet fabric fibers and to assist in blending the stream of air that flows into each aperture 22.

[0025] A head device 10 such as shown in Figure 1 may be approximately 3" to 5" wide and have 8 to 15 apertures. The apertures may be approximately 0.1" to 0.3" wide and have an aperture length of about 0.5" to 0.6". In some embodiments the aperture may be approximately 0.54".

[0026] In the following descriptions of new embodiments, each embodiment is described with reference to the description set forth in Figure 1, and the variations in design described with reference to Figure 1 may also apply to any of the new embodiments mutatis mutandis. Therefore, for conciseness, only the principal distinctions and variations of each new embodiment vis-a-vis the embodiment depicted in Figure 1 are described.

[0027] Figures 2A-2B depict a first new embodiment of an extractor head 110. In this embodiment, the projection 40 seen in Figure 1 has been removed, such that the upper surface 126 of the base plate 118 is substantially flat. The apertures 122 have been beveled or countersunk into the upper surface 126. This shortens the throat of each individual aperture 122, such that the length of the apertures 122 is determined solely by the top-to-bottom thickness of the base plate 118. In one embodiment the distance from the upper surface 126 to the lower surface 130, and therefore the length of the apertures, may be approximately 0.35", and within a range of 0.32" to 0.38".

[0028] Figures 3A-3B depict a second new embodiment of an extractor head 210. This embodiment is similar to the first new embodiment, except that for each aperture 222, a hole 228 orthogonal to the orientation of the throat is drilled from the throat to the trailing surface. The holes 228 may range in diameter from 1/16" to i", but preferably the holes 228 are substantially the same diameter as the apertures 222. In one embodiment, the holes 228 are 118" in diameter. In one embodiment the distance from the upper surface 226 to the lower surface 230, and therefore the length of the apertures, may be approximately 0.35", and within a range of 0.32" to 0.38".

[0029] Figures 4A-4B depict a third new embodiment of an extractor head 310. The extractor head base plate 318 has a flat upper surface 326 and a flat lower surface 330. The apertures 322 each have a beveled upper end. In one embodiment the distance from the upper surface 326 to the lower surface 330, and therefore the length of the apertures, may be approximately 0.35", and within a range of 0.32" to 0.38".

[0030] Figures 5A-5B depict a fourth new embodiment of an extractor head 410. The extractor head base plate 418 has a flat upper surface 426 and a flat lower surface 430. The apertures 422 each have a beveled upper end. For each aperture 422, a hole 428 orthogonal to the orientation of the throat is drilled from the throat to the trailing surface. The holes 428 may range in diameter from 1/ 16" to 1/ 4", but preferably the holes 428 are substantially the same diameter as the apertures 422. In one embodiment, the holes 428 are 118" in diameter. In one embodiment the distance from the upper surface 426 to the lower surface 430, and therefore the length of the apertures, may be approximately 0.35", and within a range of 0.32" to 0.38".

[0031] Figures 6A-6B depict a fifth new embodiment of an extractor head 510. In the fifth new embodiment, the upper surface 526 of the base plate 518 has a trough 512 defining the area of the upper surface 526 where the apertures 522 are located. The trough 512 may be machined down such that it is 1/ 16" to 1/ 4" below the upper surface 526 of the base plate 518. In the embodiment depicted in Figure 6, the trough is machined to 1/8" below the upper surface of the base plate 518. The apertures 522 are beveled at the upper end where each aperture 522 engages the trough 512. The apertures 522 on the lower surface 530 of the face plate 518. In one embodiment the distance from the upper surface 526 to the lower surface 530 may be approximately 1/3", and if the trough is approximately 1/8" deep, then the apertures in such embodiment are approximately 0.215" long, or otherwise within a range of 0.19" to 0.24".

[0032] Figures 7A-7B depict a sixth new embodiment of an extractor head 610. This embodiment is similar to the first new embodiment in that the base plate 618 has a flat upper surface 626, without any projection added above it. The upper ends of the apertures 622 are not beveled. The lower ends of the apertures 622 are beveled. In one embodiment the distance from the upper surface 626 to the lower surface 630, and therefore the length of the apertures, may be approximately 0.35", and within a range of 0.32" to 0.38".

[0033] Figures 8A-8B depict a seventh new embodiment of an extractor head 710. This embodiment is similar to the first new embodiment in that the base plate 718 has a flat upper surface 726, without any projection added above it. Both the upper ends and the lower end of the apertures 722 are beveled. In one embodiment the distance from the upper surface 726 to the lower surface 730, and therefore the length of the apertures, may be approximately 0.35", and within a range of 0.32" to 0.38".

[0034] Figures 9A-9B depict an eighth new embodiment of an extractor head 810. In this embodiment, the projection 40 seen in Figure 1 has been removed, such that the upper surface 826 of the base plate 818 is substantially flat. The apertures 822 are not beveled on the upper surface 826. In one embodiment the distance from the upper surface 826 to the lower surface 830, and therefore the length of the apertures, may be approximately 0.35", and within a range of 0.32" to 0.38".

[0035] Figures 10A-10B depict a ninth new embodiment of an extractor head 910. In this embodiment, the projection 40 seen in Figure 1 has been removed, such that the upper surface 926 of the base plate 918 is substantially flat. The apertures 922 are oval rather than circular. The lower ends of the apertures 922 are beveled. The upper ends of the apertures 922 are not beveled. In one embodiment the distance from the upper surface 926 to the lower surface 930, and therefore the length of the apertures, may be approximately 0.35", and within a range of 0.32" to 0.38".

[0036] Figures 11A-11B depict a tenth new embodiment of an extractor head 1010. In this embodiment, the upper surface 1026 of the base plate 1018 has a trough 1012 defining the area of the upper surface 1026 where the apertures 1022 are located. The trough 1012 may be machined down such that it is 1/16" to 1/ 4" below the upper surface 1026 of the base plate 1018. In the embodiment depicted in Figure 10, the trough is machined to 1/8" below the upper surface of the base plate 1018. The apertures 1022 are oval rather than circular. The lower ends of the apertures 1022 are beveled. The upper ends of the apertures 1022 are not beveled. In one embodiment the distance from the upper surface 1026 to the lower surface 1030 may be approximately 1/3", and if the trough is approximately 1/8" deep, then the apertures in such embodiment are approximately 0.215" long, or otherwise within a range of 0.19" to 0.24". [0037] Figures 12A-12B depict an eleventh new embodiment of an extractor head 1110. In this embodiment, the projection 40 seen in Figure 1 has been removed, such that the upper surface 1126 of the base plate 1118 is substantially flat. The apertures 1122 are not beveled on the upper surface 1126. The lower surface 1130 of the plate 1118 further includes a groove 1112 machined along the apex. In this embodiment, the groove 1112 is located along the downward-facing apex of the lower surface and passes substantially through the center of each aperture 1122 at the widest point of the apertures 1122. The groove may optionally be located closer to the leading edge or the trailing edge of the base plate 1118. The groove in the presently depicted embodiment has a depth of 1/16". The depth may vary from 1 / 32" to 1/ 8". In one embodiment the distance from the upper surface 1126 to the lower surface 1130 may be approximately 113" , and if the trough is approximately 1/8" deep, then the apertures in such embodiment are approximately 0.215" long, or otherwise within a range of 0.19" to 0.24".

[0038] Figures 13A-13B depict a twelfth new embodiment of an extractor head 1210. In this embodiment, the upper surface of the base plate 1218 has a trough 1212 defining the area of the upper surface 1226 where the apertures 1222 are located. The trough 1212 may be machined down such that it is 1/16" to 1/ 4" below the upper surface 1226 of the base plate 1218. The apertures 1122 are not beveled on the upper surface 1226. In the embodiment depicted in Figure 13, the trough is machined to 1/ 8" below the upper surface of the base plate 1218. The lower surface 1230 of the plate 1218 further includes a groove 1214 machined along the bottom surface. In this embodiment the groove 1214 is located along the downward-facing apex of the lower surface and passes substantially through the center of each aperture 1222 at the widest point of the apertures 1222. The groove may optionally be located closer to the leading edge or the trailing edge of the base plate 1218. The groove in the presently depicted embodiment has a depth of 1/16". The depth may vary from 1 / 32" to 1/ 8". In one embodiment the distance from the upper surface 1226 to the lower surface 1230 may be approximately 113" , and if the trough is approximately 1/8" deep, then the apertures in such embodiment are approximately 0.215" long, or otherwise within a range of 0.19" to 0.24".

[0039] Figures 14A-14B depict a thirteenth embodiment of extractor head 1310. In this embodiment, the upper surface 1326 of the base plate 1318 has a trough 1312 defining the area of the upper surface where the apertures 1322 are located. The trough 1312 may be machined down such that it is 1/16" to 1/4" below the upper surface 1326 of the base plate 1318. The apertures 1322 are not beveled on the upper surface 1326. In one embodiment the distance from the upper surface 1326 to the lower surface 1330 may be approximately 1/3", and if the trough is approximately 1/8" deep, then the apertures in such embodiment are approximately 0.215" long, or otherwise within a range of 0.19" to 0.24".

[0040] These various embodiments have been tested on different surfaces for cleaning liquids. These surfaces included carpets using nylon, polyester, and olefin fibers. One measurement of efficiency is to perform, first for each "run," a wet or cleaning pass over a defined carpet area with a 50% overlap which deploys and then vacuums up the solution, and then second, a dry pass with the same 50% overlap to extract the remaining solution. A 50% overlap is making a first pass line across a carpet with a vacuum, repositioning the vacuum so that it covers half of the first pass line while the other half is positioned over unvacuumed carpet, and making a second pass line, and so on, until the entire area of the carpet to be cleaned has been passed. Using a 50% overlap effectively results in the cleaned area having two pass lines per pass of the vacuum over the whole area while minimizing the total number of pass lines for cleaning the carpet. (It should be noted that the left-most and right-most portions of the carpet may only have a single pass line if bounded by a wall such that the vacuum cannot make a half-pass over the left-most or right-most line, and if not otherwise passed over using a cleaning wand, small area nozzle, or similar device for cleaning small areas near walls. So long as the testing below is performed uniformly (i.e., the left-most and right-most areas are either cleaned using the same method, or not cleaned at all), this will have no effect on the efficiency testing.) It will be appreciated that developments in efficiency of the extraction head will improve the carpet cleaning device by reducing the dry times associated with vacuum extraction and allows the carpet to be ready for use more quickly after cleaning.

[0041] To measure efficiency per run, the following test was conducted. For each run for a set of extractor heads, a 25 square foot area of carpet was sprayed down with 0.2183 US liquid gallons (27.94 US fl oz, 0.8264 L) of water. The area of carpet was then vacuumed using a wet pass for 30 seconds using a 50% overlap. The area of carpet was then vacuumed using a dry pass for 30 seconds using a 50% overlap. After completing the dry pass, the vacuum or cleaning machine was permitted to run an additional 30 seconds in order to ensure that all waste removed from the carpet passed through the cleaner and into the extraction tank. No heat was applied during either cleaning pass. The tank was weighed to determine the water absorption for the given run.

[0042] The vacuum extractor heads were tested using the following carpet fiber types: nylon, olefin, and two types of polyester. Multiple runs (at least five) were made for each extractor head embodiment for each carpet being tested. The water extracted from each run was measured and compared to the amount of water actually applied, and a percentage of water extracted was calculated for the run. The average percent of water extracted in connection with a given extractor head embodiment for a particular type of carpet was then calculated. These averages are shown in Table 1 below.

[0043] Figure 1 above refers to the known extractor head design currently used in the marketplace depicted in Figure 1. Figures 2-14 refer to the new embodiments described above with respect to each figure. The embodiments were tested in the order listed above. In addition, it is known that as a carpet is subject to repeated vacuum runs, the efficiency in removing water content from the carpet is reduced with each subsequent vacuum run. Therefore, the original embodiment of Figure 1 was tested with a second set of runs over the test carpets to provide a gauge of carpet degradation resulting from the multiple vacuum runs. [0044] For purposes of this test, each extractor head was approximately 5.56" wide, and had a distance between the upper surface and the bottom of the lower surface of approximately 0.34". For those embodiments with a trough on the upper surface, the trough was approximately 118" deep from the upper surface. For those embodiments with a groove on the lower surface, the groove was approximately 1/16". Each embodiment with circular apertures had 10 apertures across the base plate, wherein the circular apertures were 0.2" in diameter. The embodiments with oval apertures had 10 apertures, each aperture having a major diameter (i.e., the measurement of the length of the oval cross-section) of approximately 1/4". [0045] To provide a comparison between the various embodiments, Table 2 below shows the percentage of water extracted compared against the first set of runs on the embodiment of Figure 1. That is, if an embodiment shows greater than 100%, the extractor head embodiment extracted more water than the original embodiment of Figure 1 in its first runs on a given type of carpet. If an embodiment shows less than 100%, the extractor head embodiment extracted less water than the original embodiment of Figure 1 in its first runs on a given type of carpet.

[0046] The results demonstrate significant improvements shown in the embodiments of Figures 6 and 9-14.

[0047] It is to be understood that the above-described arrangements are only illustrative of the application of the principles of the present invention. Numerous modifications and alternative arrangements may be devised by those skilled in the art without departing from the spirit and scope of the present invention and the appended claims are intended to cover such modifications and arrangements. Thus, while the present invention has been shown in the drawings and fully described above with particularity and detail in connection with what is presently deemed to be the most practical and preferred embodiment(s) of the invention, it will be apparent to those of ordinary skill in the art that numerous modifications, including, but not limited to, variations in size, materials, shape, form, function and manner of operation, assembly and use may be made, without departing from the principles and concepts of the invention as set forth in the claims.