US3524213A

US3524213A - Vacuum head

Info

Publication number: US3524213A
Application number: US747058*A
Authority: US
Inventors: Mayer Spivack
Original assignee: Individual
Current assignee: Individual
Priority date: 1968-06-17
Filing date: 1968-06-17
Publication date: 1970-08-18
Anticipated expiration: 1987-08-18

Description

Aug. 18, 1970 M. sPwAcK 3,524,213

' l VACUUM. HEAD Filed June 17, 1968 s sheets-sheet v1 i N g) //VENTAR Alg- 18; 1970 M. sPlvAcK- l 3,524,213

y vAcuUM HEAD Filed June 17. 1968 a sheets-sheet z llll mu m2 m7 l|\ l 7 na .fm |23 |04 Aug. 18, v1970 M. sPlvAcK 3,524,213

VACUUM HEAD Filed June 17, 1968 :S Sheets-Sheet 5 United States Patent O 3,524,213 VACUUM HEAD Mayer Spivack, 72 Proper-zi Way, Somerville, Mass. 02143 Continuation-impart of application Ser. No. 542,281, Apr. 13, 1966. This application June 17, 1968, Ser. No. 747,058

Int. Cl. A471 5/34, 9/ 06 U.S. Cl. -354 21 Claims ABSTRACT OF THE DISCLOSURE A vacuum cleaner head having a vhood with a skirt defining a lower surface maintained in spaced relation to the oor. Passages are formed from the periphery of the hood to an aperture in the hood. Venturi constrictions are provided in the passage in the form of flexible resilient walls which are adapted to open wider from a preset position to permit passage of large objects. The exible walls are formed preferably of a thin llexible strip of metal or the like that lies partially in two passages and is shaped and arranged in such a manner as to constrict one passage when the other passage is being widened.

CROSS REFERENCE TO RELATED APPLICATIONS This is a continuation-in-part of application Ser. No. 542,281, filed Apr. 13, 1966 and now abandoned.

SUBJECT MATTER OF THE INVENTION The present invention relates to a vacuum cleaner head especially designed to pick up small particles of relatively high density.

BACKGROUND OF THE INVENTION Commercially available vacuum cleaner heads frequently are incapable of picking up relatively small particles such as nails, metal shavings, stones, gravel, sand, glass and the like. Furthermore, such vacuum cleaner heads often are not especially designed for use on hard surfaces, such as oors. Consequently such vacuum cleaner heads are not particularly designed for industrial use. Presently available vacuum cleaner heads, moreover, do not make maximum use of their power and dissipate a large amount of the lifting force provided in the vacuum cleaner in poorly designed vacuum cleaner heads.

Further insofar as is known no commercially available vacuum cleaner head used either on floors or on rugs or the like provides a head having apertures that dynamically vary in size and provide dynamic venturi openings or passages that are directly related to particles that are being picked up.

BRIEF DESCRIPTION OF THE INVENTION The present invention is designed to provide a vacuum cleaner head which overcomes these and other disadvantages of presently available vacuum cleaner heads.

The present invention provides a vacuum cleaner head -Which is capable of maximizing the eiciency of a vacuum source by first accelerating particles to be swept up in a horizontal direction and then subsequently in a vertical direction through the ducts or tubes connected to the vacuum source. These particles are accelerated to the maximum velocity of the system in their initial horizontal direction of movement by use of a venturi effect. The present invention also provides a construction which is particularly adapted for use on hard surfaces but which may also be used on other surfaces such as rugs with a high degree of efficiency.

The present invention also provides a vacuum cleaner head which is self cleaning, -simple to manufacture, mainice tain, and repair. A further object of this invention is to provide a lightweight vacuum cleaner head which is relatively low in height and, therefore, capable of moving under low objects.

The present invention also provides a vacuum cleaner head having passages which extend radially from the aperture in the hood of the vacuum cleaner head with venturi constrictions in the passages. In this invention the venturi constrictions are preferably dynamically formed so as to vary the dimensions of the passages in conformity with the particles being sucked through the head.

In the present invention the vacuum cleaner head comprises primarily a hood having a skirt with a lower surface having depending means defining one or more passages extending in a plane parallel to the lower surface of the hood. These passages extend radially from an aperture in the hood and are provided with venturi constrictions in the passage. In a preferred form the venturi constrictions are formed of flexible wall members adapted to be moved dynamically while air is passing through the passage vwith the exi-ble wall members adapted to widen one passage and constrict another passage from a preset position simultaneously during operation of the cleaner.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing objects and advantages of the present invention will be more clearly understood when considered in conjunction with the accompanying drawings in which:

FIG. 1 is a top plan View of a vacuum cleaner head embodying the invention;

FIG. 2 is a cross-sectional view taken along the line 2-2 of FIG. l;

FIG. 2A is a cross-sectional view taken along the line 2A-2A of FIG. 1 and forming a substantial continuation of the cross-sectional view taken along the line 2-2 of FIG. l;

FIG. 3 is a bottom, partially fragmented view;

FIG. 4 is a bottom plan view of a modification of the invention;

FIG. 5 is a cross-sectional view taken substantially along the line 5-5 of FIG. 4;

FIG. 6 is a bottom plan view of a preferred embodiment of the invention; and

FIG. 7 is a cross-sectional View taken substantially along the line 7-7 of FIG. 6.

DESCRIPTION OF PREFERREDl EMBODIMENTS The vacuum cleaner head illustrated is designed primarily for use in removing particles or dust from a flat surface and is particularly designed for removing relatively heavy particles from a floor or like flat surface. The location of such a surface relative to the vacuum cleaner head when used is illustrated at 1 in FIGS. 2 and 2A. The vacuum cleaner head has a hood 2. This hood comprises a skirt 3 and an annular conic wall 4 with the annular conic wall 4 and skirt 3 preferably integrally formed and continuous with one another. The conic wall 4 is preferably centrally located with respect to the skirt 3. If desired, the wall 4 and skirt 3' may be formed of a single piece of injection-molded plastic. If desired, the hood 2 may be formed of a transparent plastic to permit viewing of the surface to be cleaned and of the particles as they accelerate in a horizontal plane under the skirt. The skirt 3 is formed with a lower surface 5 and outer periphery 6. The lower surface 5 is maintained in spaced relation to the flat surface or floor 1 by spacing means which may, for example, comprise at least three adjustable dependent posts 7 intermittently spaced about the lower surface 5. These posts may be adjusted to variable lengths by suitable adjusting means. For example, each post may have an outer portion 7a and an inner portion 7b having complementary threaded portions adapted to permit elongation of the post 7 by adjusting the outer portion relative to the inner portion. If desired, these posts may be provided with friction engaging outer coverings or sleeves 8 formed of a material having a relatively low coeicient of friction, such as Teon or the like. The inner surface of sleeve 8 may be longitudinally serrated to engage cornplementary serrations on the outer surface of posts 8 to restrain rotation of portion 7a relative to portion 7b. If desired, such spacing means may also comprise wheels instead of the xed spacing means 7 which are also suitably adjustable to different heights so as to maximize the eiciency of the vacuum head for different purposes. If desired, the posts 8 may carry wheels as illustrated at 8.

If desired, a bumper 65 of a exible strip of magnetic material may be suitably secured about the periphery of the skirt 3. This strip functions both as a non-abrasive bumper and as a means for picking up metal particles.

A plurality of means extend downwardly from the lower surface and define a plurality of passages 10, 11 and 12, with these passages 10, 11 and 12, having their upper and lower surfaces formed respectively by the lower surface 5 and the flat surface of the oor 1. The plurality of means which extend from the lower surface 5 to form the sidewalls of these passages 10, 11 and 12 may comprise either a solid member or a brush. Thus, for example, these means may comprise brushes 14, 15 and 16. The brushes are suitably secured at their upper end to the lower surface 5 and extend downwardly towards the at surface 1 and are spaced close to the fioor 1, as for example, one sixteenth of an inch away from or ilush with the floor, being maintained a distance away from the oor by the height of the spacing means 7. The sidewalls 17 of these brushes are generally ared outwardly from their inner or one end to the other or outer end of the passages 10, 11 and 12. Preferably this daring is substantial and may be formed by arranging the sidewalls 17 in an arcuate configuration as illustrated in FIG. 3. If the members 14, 15 and 16 are formed as brushes, the brushes should be relatively dense and stiff so as to effectively form a relatively tight packed barrier to the passage of air, dust particles or other foreign material therethrough.

Means forming a venturi constriction extend across each of the passages 10, 11 and 12 near the outer end. Each means may comprise, for example, the downwardly extending projection integrally formed on the lower surface 5. These downwardly extending projections 20 preferably extend in a longitudinal arc with the ends of the arc terminating at the sidewalls 17 of adjacent, downwardly extending projections. Preferably, the inner edge of these projections 20 extend to the surface 5 at a sharp angle, as illustrated at 21, while the outer surface may be tapered as illustrated at 22.

The inner ends of the passages 10, 11 and 12 are each connected respectively to one of the

conduit portions

30, 31 and 32 and form continuous connections therewith. These conduit portions each extend parallelly upward through an aperture 34 in the skirt 3 which aperture is defined by the wall 4. These

conduit portions

30, 31 and 32 are formed by a septum 37. The septum 37 has a plurality of channels 38, 39 and 40 in its outer surface longitudinally extending from the lower to the upper ends of this septum 37. The channels 38, 39 and 40 are preferably semi-circular in cross section, with a diameter at the lower ends continuous with the inner ends of the passages 10, 11 and 12, with which they are aligned, so that the passages and conduits converge smoothly into one another and with the conduits extending angularly upwardly through the aperture 34 from the horizontally planar passages 10, 11 and 12. The septum 37 may be suitably secured with its outer walls fixed to the inner surface of the angular wall 4 by suitable means such as a plurality of screws 50 which extend through the Wall 4 into the septum 37. The lower end of the septum 37 has secured to it a scoop 51. This scoop 51 is formed with a circular lip 52 having a circular peripheral edge 53 adapted to press against the fiat surface of a floor. This scoop 51 is preferably formed of resilient material so that the edge 53 will closely engage the floor. The surface 52 of the scoop is arcuately curved upwardly to direct particles moving inwardly through the passages upwardly through the

conduit portions

30, 31 and 32. Preferably, this scoop 51 is secured to the septum 37 with an intermediate resilient foam or compressible section 55 which is adapted to take up` any irregularities that may occur in the floor or surface over which the vacuum cleaner is moving while maintaining the edge 53 in close adjacency to the Hat surface.

The upper edge of the annular wall 4 is formed with means suitable for engaging the vacuum cleaner head with a tube or nozzle of a vacuum cleaner. If desired, this may comprise an inwardly extending bead adapted to engage a recess or other suitable engaging element on a vacuurn cleaner tube nozzle.

Although this embodiment illustrates a vacuum cleaner head having a circular configuration other configurations are contemplated. For example, triangular, rectangular, eliptical or square heads more adapted to iit into corners may embody this invention.

Turning now to FIGS. 4 and 5 there is illustrated an embodiment of the invention utilizing a passage having a dynamic venturi constriction. In this arrangement the hood which is preferably made of a transparent material has a forward or mouth end 101. Depending from the lower surface 102 of the hood 100 are a plurality of downwardly projecting

members

103 and 104 which cooperate to define a plurality of

passages

105 and 106. These

passages

105 and 106 extend radially from an aperture 107 to the forward or mouth end 101. The aperture 107 extends upwardly through the hood 100 and is provided with means suitable for attachment to a vacuum hose or other suction element. The downwardly projecting element 104 in the embodiment described, is preferably in the shape of an island having a uniform thickness and

flat walls

109 and 110 angularly arranged. Walls 109 project forwardly and function to divert particles rearwardly to the

passages

105 and 106. Walls 110 converge and form respectively one-half each of the

passages

105 and 106. The downwardly projecting member 103 is formed with

forward walls

112 and 113 which converge rearwardly of the aperture 107 and cooperate respectively with the walls to form the

passages

105 and 106.

The

passages

105 and 106 are each provided with venturi constrictions. These venturi constrictions are formed by

flexible walls

114 and 115. The exible walls 114 project from the

walls

112 and 113, while the flexible walls project from the walls 110. Preferably the

llexible walls

114 and 115 are formed of an elongated metal member or strip which is suitably and preferably solidly anchored at their ends respectively in the downward projecting

members

103 and 104. Thus slots are formed in

members

103 and 104 to receive the ends of

ilexible walls

113 and 114 in securing relation. The wall 114 which extends in the

passage

105 and 106 is formed with curved sections 114A, 114B and 114C connected integrally and in series with the bowed portion 114B arcuately curved rearwardly around the aperture 107 and the bowed portions 114A and 114C both bowed forwardly or in a direction opposite to the direction of bow of section 114B. Flexible wall 115 extends from passage 105 to passage 106 and is anchored at its ends in the downwardly projecting member 104 in a manner similar to the means for securing the exible wall 114 at its ends in downwardly projecting member 103. Preferably the flexible wall 115 is arcuately curved around the intersection of walls 110 forwardly of the aperture 107. Bowed portion 115A is positioned opposite bowed portion 114A while bowed portion 115C is positioned opposite bowed portion 114C.

The

walls

114 and 115 may be secured respectively at their ends in slots 114D and 115D in turn extending upwardly in

members

103 and 104. If desired, legs 120 may be provided at the corners of the hood 100 to raise the unit to a selected height over a floor. Each leg may be adjusted to different heights against the tension of spring 121, bearing between the hood 100 and head 122 of the threaded leg 120, by adjusting the locknut 123 which is threaded on the leg 121.

In the operation of the embodiment of the invention illustrated in FIGS. 4 and 5, a Vacuum connection is suitably connected to the aperture 107 and the unit is moved over a floor that is to be cleaned. Particles are drawn through the

passages

105 and 106 upwardly through the aperture 107. If a large particle is drawn through one of the passages, for example passage 105, and its dimension is greater than the preset distance between the opposed surfaces of the walls 114C and 115C, these walls will be forced apart by the increased air pressure around the particles between them, or by mechanical forces resulting from contact with the obstruction itself. At the same time the opposite ends of the

walls

114 and 115 in the area of sections 114A and 115A will close. This closure in the passage 106 will cause increased force in the flow of air through passage 105 thus accelerating the forces on the particle as it moves towards aperture 107.

The

walls

114 and 115 may be damped or undamped, depending upon the specific application for which the unit is intended. If the walls are undamped, they are formed of a spring metal of uniform thickness. If the springs are damped they may be formed of a lamination of spring metal and damping material such as cloth, rubber, plastic or leather, as illustrated.

Turning now to FIGS. 6 and 7, there is illustrated a preferred embodiment of the present invention. In this arrangement, the hood 200 is provided with a forward or leading edge 201 and a trailing edge 202. Depending from the hood is a plurality of downwardly projecting

members

203, 204 and 205 which cooperate to form

forward passages

206 and 207 and rearwardly extending passage 208. The downwardly extending member 203 is provided with two

legs

210 and 211 which extend from a forward vertex 213 rearwardly. The inner surface of these

legs

210 and 211 are substantially parallel to walls of the depending or downwardly projecting

members

204 and 205 and cooperate therewith to form the

passages

206 and 207. The lower surfaces of downwardly extending

members

204 and 205 are flat and adapted to lie parallel to the surface of the floor on which they move. Preferably positioned within these downwardly extending members and projecting downwardly therefrom are the

brushes

230 and 231. These brushes may be conventionally formed and may, if desired, be freely rotatable or, alternately, driven for purposes of picking up or driving dust towards one or the other of the passages.

Positioned within passages 2016 and 207 are the

flexible wall members

215 and 216. Also positioned in

passages

206 and 207 are the

flexible wall members

221 and 222. The

exible wall members

221 and 222 are arcuately curved over the forward edges of the downwardly extending members 204 and 20S and from thence extend rearwardly through the passage 208. The

wall members

215 and 216 are preferably formed of a single elongated piece of flexible resilient metal which may be damped or undamped as previously described in connection with the embodiment of FIG. 4. This elongated metal member has two rearwardly bowed portions which lie adjacent the

walls

210 and 211 and are secured at their ends at the ends of these

walls

210 and 211. The intermediate portion of the

flexible wall members

215 and 216 extends forwardly in between the aperture 202 and the rear surface of the downwardly projecting member 203. If desired it may be supported against movement in this area by the pins of projections 225 which project on either side of the exible wall. The

flexible walls

221 and 222 extend into passage 208 and are anchored at the outer end of passage 208 respectively in the depending

members

204 and 205. The other ends of these

flexible wall members

221 and 222 are also anchored respectively in the downwardly extending

members

204 and 205 but on the other side of these members opposite the

walls

211 and 210 respectively. The venturi effect formed by the opposed portions of

walls

215 and 221 in passage 2016 and by

walls

216 and 222 in passage 207 is similar to that as effected in the flexible walls of FIG. 4. Similarly the

exible walls

221 and 222 in passage 208 form a venturi effect for material picked up by the head on rearward movement of it. In that arrangement the movement of the

walls

221 and 222 will simultaneously close both of the

passages

206 and 208. Thus, in other words, the passage of an article through any one of the Venturi constrictions formed by the flexible walls will effectively close or narrow the venturi constrictions in the other passages.

The forward edge or wall of the hood is also provided with a pair of

venturi members

217 and 218 which may be damped or undamped similar to

walls

114 and 115. These

venturi members

217 and 218 comprise primarily flexible wall members having offset sections 217A and 217B in flexible wall member 217 and flexible wall sections 218A and 218B in flexible wall member 218. The offset sections 217B and 218B are respectively secured to the undersurface of the hood. The other portions 217A and 218A which may be slotted from the free edge as indicated at 217C and 218C, project downwardly and are spaced from the lower surface of the hood and provide venturi effects which may be deflected upon passage of articles between the hood and the surface over which the hood is being moved.

If desired, the hood may be provided with legs generally indicated at 240. These legs should preferably be adjustable and in this connection are provided with Shanks 241 which project preferably through the hood. The lower end of the legs is formed with a rolling or sliding tip 242. The nut 243 is threaded on the shank 241 and prevents upward movement of the leg through the hood. A spring 244 coaxial with the shank has one end bearing against the upper surface of the hood and the other end bearing against a knob or handle 245. Thus the leg is tensioned upwardly against the stop nut 243 and may be adjusted by rotating the stop nut 243 against the tension of the spring 244.

The hood 200 may be formed with a fixed shroud 250 as illustrated in FIG. 7 adapted to be connected to a vacuum source. Alternately, this shroud may be provided with a universal tubular joint designed to permit the free end of the shroud to pivot with respect to the portion immediatelyabove hood 200. Suitable detents may be provided to normally limit universal movement to movement in forward and rear directions unless an overriding force is applied.

Having now described my invention, I claim:

1. A vacuum cleaner head for use in removing particles from a at surface comprising, a hood having a skirt with a lower surface, means for maintaining said lower surface in spaced relation to said flat surface, means extending from said lower surface defining a passage with one end of said passage adjacent an aperture in said lower surface and the other end intermediate said aperture and the peripheral edge of said lower surface, said pas# sage defining means comprising a plurality of downwardly extending elements having lower surfaces extending close and parallel to said fiat surface and sidewall members ared apart toward to said other end of said passage whereby the cross-sectional area of said passage is greater in portions closer to the other end of said passage than in portions remote therefrom, means forming a venturi constriction in said passage at said other end of said passage, means forming a conduit extending angularly from said aperture with one end connected to said aperture of said head and the other end of said conduit means adapted to receive a suction hose, whereby said passage and conduit form a continuous passageway with the portion thereof formed by said passage parallel to said flat surface and angular to said conduit, means projecting downwardly from said one end adjacent said conduit and having a surface forming a scoop with the lower edge extending across said passage at said one end close to said flat surface.

2. A vacuum cleaner as set forth in claim 1 having a septum with walls forming portions of said conduits.

3. A vacuum cleaner as set forth in claim 2 having a plurality of said passages.

4. A vacuum cleaner as set forth in claim 3 wherein said spacing means are adjustable for adjusting the area of said passage at said venturi-forming means.

5. A vacuum cleaner head for use in removing particles from a flat surface comprising, a hood having a skirt with a lower surface, means for maintaining said lower surface in spaced relation to said flat surface, means extending from said lower surface defining a passage with one end of said passage adjacent an aperture in said lower surface and the other end intermediate said aperture and the peripheral edge of said lower surface, said means defining a passage comprising a plurality of downwardly extending elements having sidewall members flared outwardly from said one end toward said other end whereby the cross-sectional area of said passage is greater in portions closer to said other end than in portions remote therefrom and with each of said passages continuous with one of a plurality of separate parallel conduits, means forming a venturi constriction in said passage at said other end of said passage, said venturi-forming means extending across each of said passages with each comprising a projection extending downwardly from said lower surface with the end of said projection terminating adjacent one of said downwardly extending elements, means forming a conduit extending angularly from said aperture with one end connected to said aperture of said head and the other end of said conduit means adapted to receive a suction hose, whereby said passage and conduit form a continuous pasasgeway with a portion thereof formed by said passage parallel to said ilat surface and angular to said conduit, said means forming a conduit formed of an annular wall with its lower edge continuous with said skirt, a septum positioned within said annular wall said septum having an outer wall with a plurality of spaced downwardly extending channels formed therein and defining with the inner surface of said conduit said plurality of separate parallel conduits.

6. A vacuum cleaner as set forth in claim 5 wherein said skirt is transparent and said spacing means includes a plurality of wheels.

7. A vacuum cleaner head for use in removing particles from a flat surface comprising, a hood having a skirt with a lower surface, means for maintaining said lower surface in spaced relation to said flat surface, means extending from said lower surface defining a passage with one end of said passage adjacent an aperture in said lower surface and the other end intermediate said aperture and the peripheral edge of said lower surface, means forming a venturi constriction in said passage at the other end of said passage, means forming a conduit extending angularly from said aperture with one end connected to said aperture of said head, and the other end of said conduit means adapted to receive a suction hose, whereby said passage and conduit form a continuous passageway with a portion thereof formed by said passage parallel to the flat surface and angular to said conduit, and having a septum with walls forming portions of said conduit and with said septum terminating at its lower end in a scoop at said one end of said passage.

8. A vacuum cleaner head as set forth in claim 7 CTI wherein said septum is formed with a transverse section of resilient compressible material.

9. A vacuum cleaner head as set forth in claim 5 having a flexible magnetic strip encircling said skirt, and said strip comprising a bumper means.

10. A vacuum cleaner head for use in removing particles from a fiat surface comprising, a hood having a skirt with a lower surface, means for maintaining said lower surface in spaced relation to said flat surface, means extending from said lower surface defining a passage with one end of said passage adjacent an aperture in said lower surface and the other end intermediate said aperture and the peripheral edge of said lower surface, said passage defining means comprising a plurality of downwardly extending elements having sidewall members flared apart toward said other end of said passage whereby the crosssectional area of said passage is greater in portions closer to the other end of said passage than in portions remote therefrom, means forming a venturi constriction in said passage at said other end of said passage wherein said venturi constriction extends downwardly from said lower surface and comprises a ridge extending from one sidewall member to the other, means forming a conduit extending angularly from said aperture with one end connected to said aperture of said head and the other end of said conduit means adapted to receive a suction hose, whereby said passage and conduit form a continuous passageway with a portion thereof formed by said passage parallel to said flat surface and angular to said conduit.

11. A vacuum cleaner head in accordance with claim 10 wherein a plurality of means extend from the lower surface to define a plurality of passages with one end of each passage adjacent said aperture and the other end of each passage intermediate said aperture and the peripheral edge of said lower surface, and a plurality of means forming a plurality of conduits extending angularly from said aperture.

12. A vacuum cleaner head for use in removing particles from a flat surface comprising, a hood having a skirt with a lower surface, means projecting from said lower surface defining at least one passage positioned inwardly from the edge of said skirt, means forming an aperture in said skirt remote from the edge thereof in fluid communication with said passage, said means projecting from said lower surface including walls extending generally radially from said aperture and having intermediate their length means forming a venturi constriction.

13. A vacuum cleaner head as set forth in claim 12 wherein said walls include at least in part a flexible wall adapted to be moved dynamically while air is passing through said passage to Vary the dimensions of said passage.

14. A vacuum cleaner head as set forth in claim 13 including a pair of flexible walls on opposite sides of said passage.

15. A vacuum cleaner head as set forth in claim 14 including a plurality of passages with each passage having said flexible walls therein.

16. A vacuum cleaner head as set forth in claim 15 including said flexible walls formed of elongated, flexible members, and means securing said flexible members at their ends to said downwardly projecting member.

17. A vacuum cleaner head as set forth in claim 16 wherein said hood has a forward end and a rear end and two of said passages extend forwardly of said hood and one of said passages extends rearwardly of said hood.

18. A vacuum cleaner head as set forth in claim 12 including, a plurality of said passages, means positioned in said passages for simultaneously opening one passage while a second passage is being closed.

19. A vacuum cleaner head as set forth in claim 18 wherein said means positioned in said passage includes an elongated, flexible strip extending from one passage 9 10 to a second passage and forming a flexible wall adapted References Cited to simultaneously expand the cross-sectional area of one UNITED STATES PATENTS passage and constrlct the cross-sectional area of a second passage 1,109,525 9/ 1914 Hartwell.

another. ROBERT W. MICHELL, Primary Examiner 21. A vacuum cleaner head as set forth in claim 20 10 U.S. Cl. X.R. wherein said exible strip is resilient. 15-398, 419