Vacuum sweeper drive belt

Abstract: An endless elastomeric vacuum sweeper belt (28) for use in a vacuum sweeper (10) having a diamond pattern drive surface. A first set of ribs (38) project inwardly in a substantially diagonal direction along the drive surface of the belt. A second set of ribs (40) project inwardly along the drive surface (30) of the belt in a substantially diagonal direction opposite the direction of the first set of ribs. The first and set second set of ribs together define a diamond-like pattern on the drive surface as well as a number of particle recesses (42) for the temporary collection of matter. Each rib includes knife-like edge portions (44) to increase the traction of the belt on a drive surface by cutting, loosening and expelling foreign matter lodged between the belt drive surface and the rotation member and/or the drive source of the vacuum sweeper.

Description: This invention relates to a drive belt for a vacuum sweeper. Elastomeric endless power transmission belts are well known and widely used in apparatus such as yarn-processing machines, combustion engines, and vacuum sweepers. Historically, drive belts were made from leather or cloth belting sewn together at the ends to define an endless loop. Over time, more elastic and less expensive materials, i.e. synthetic rubber, has been substituted for leather and cloth in the manufacture of drive belts. Modern vacuum sweeper belts are typically cylindrical or rectilinear in shape to maximize the surface of the belt which drivingly engages the brush roll of the sweeper. The belt drive surface is usually smooth, unperforated and free of any traction enhancing features. One historical problem with the design of vacuum sweeper drive belts is caused by the collection of dirt, hair, carpet fibers and other foreign matter on the brush roll during operation of the sweeper. The matter works its way between the drive surface of the belt and the brush roll reducing the traction, and increasing the slippage, of the drive belt on the brush roll. The reduced traction results in slower revolutions of the brush roll during sweeper operation, significantly decreasing the volume of dirt and other matter picked up by the sweeper. A variety of drive belts have been designed to overcome specific problems with the apparatus on which they are deployed. U.S. Patent No. 4,034,615 discloses a drive belt having rhomboidally or trapezoidally shaped teeth disposed on the belt drive surface which operates without creating the siren-like noise characteristic of toothed belts. The apparatus disclosed in U.S. Patent No. 3,129,553 is designed to prevent the accumulation of lint on a spindle drive tape during the operation of yarn-processing machines by passing the drive surface of the tape over an idler roll having a knurled surface. The knurled surface and the centrigual force of the idler roll coact to remove lint from the tape surfaces. U.S. Patent No. 2,912,722 discloses a drafting apron having a plurality of ribs disposed on the apron drive surface. The ribs extend diagonally along the inner surface of the apron to define a criss-cross diamond-like pattern on the inner surface of the apron. None of the aforementioned belt features have been applied to vacuum sweeper drive belts to improve belt traction on the vacuum brush roll to eliminate the negative effects of unwanted matter accumulation on the roll. According to one aspect of this invention there is provided an endless drive belt for a vacuum cleaner, the belt including an inner drive surface characterised by a first set of ribs projecting inwardly from the drive surface and extending in a substantially diagonal direction across said surface, and a second set of ribs projecting inwardly from the drive surface and extending in a substantially diagonal direction across the drive surface to intersect the first set of ribs to form a diamond pattern on the drive surface, wherein the first and second sets of ribs define knife-like edges for expelling foreign matter. Preferably, the first and second sets of ribs comprise converging tapered portions to define the knife-life edges. According to another aspect of the invention there is provided a vacuum cleaner comprising a drive shaft and a brush roll, and an endless drive belt as described in either of the preceding two paragraphs extending around the drive shaft and the brush roll for continuous operation in use. A drive surface of a vacuum sweeper drive belt includes a plurality of ribs which define a diamond patterned surface to improve the belts traction on the brush roll of a vacuum sweeper. A first set of ribs project inwardly from the drive surface in a diagonal direction and a second set of ribs are disposed diagonally in the opposite direction to the first set of ribs to define the diamond-like pattern. Each rib includes converging surfaces which define knife-like edges. The knife-like edges increase the traction of the belt on the brush roll by cutting, loosening and expelling foreign matter lodged between the brush roll and the inner belt drive surface. The ribs also define a plurality of particle recesses on the inner surface of the drive belt for the temporary collection of matter loosened by the knife-like edges. Reference is now made to the accompanying drawings, in which: Figure 1 is a perspective view of a vacuum sweeper, shown in phantom, illustrating the relationship between the vacuum sweeper drive source, the drive belt and a brush roll; Figure 2 is an enlarged perspective view of the drive belt of Figure 1; and Figure 3 is an enlarged fragmentary view of the drive surface of the drive belt of Figure 2. With reference to the drawings, a typical upright vacuum sweeper 10 is shown in broken lines in Figure 1. The vacuum sweeper 10 comprises a handle 12 which is pivotally connected to a wheeled housing 14. The housing 14 includes a dust channel 18 and a nozzle 19. A power source (not shown) having a drive shaft with a belt receiving end 20 is mounted within the housing 14 and extends into the dust channel 18. A rotor (not shown) is typically secured to the central portion of the drive shaft to draw air into the nozzle 19. A dust bag 26 is flexibly connected to the dust channel 18 to receive the dirt-laden air generated during operation of the sweeper 10. A brush roll 22 having bristles 24 along its length is rotatably mounted within the nozzle 19. A vacuum sweeper drive belt 28 is wrapped around the belt-receiving end 20 of the drive shaft and the central drive surface 23 of the brush roll 22. The bristles 24 function to agitate the rug or other like surface being cleaned to loosen the dirt so that the dirt can be drawn by the flow of air into the nozzle 19 and deposited in the dust bag 26. The vacuum sweeper belt 28 includes a drive surface 30, edges 34, and an exterior surface 36. The drive surface 30 engages the belt-receiving end 20 of the drive shaft and surrounds the brush roll central drive surface 23 in driving relationship. The perpendicular orientation of the belt-receiving end 20 and the brush roll 22 creates a figure 8 path for the belt 28. The drive belt 28 is constructed in a manner that reduces the tendency of dirt, hair, etc. from accumulating on the brush roll 22 and the belt-receiving end 20 of the drive shaft with resulting reduction of traction. In accordance with the invention, the belt drive surface 30 includes a first set of ribs 38 which project inwardly and extend in a substantially diagonal direction. A second set of ribs 40 project inwardly and are disposed in a substantially opposite diagonal direction to the first set of ribs 38 to form a diamond pattern on the drive belt surface 30. The first and second sets of ribs 38, 40 also define a plurality of recesses 42 on the belt drive surface 30 that function to temporarily collect dirt and other matter during the operation of the sweeper 10. As shown in Figure 3, the first and second sets of ribs 38, 40 have converging tapered portions 43 which define knife-like traction edges 44. The edges 44 increase the traction of the belt on the central brush roll drive surface 23 and on the belt receiving end 20 by cutting, loosening and expelling foreign matter lodged between the drive surface 30, the belt receiving end 20 and the brush roll drive surface 23 during operation of the sweeper 10. Loosened matter is temporarily collected in the belt recesses 42 until the twisting figure 8 path of the belt 28 loosens and dispels the collected matter from the recesses 42. Thereafter, the air flow dislodges and deposits the collected matter in the dust bag 26. While a preferred embodiment of the invention has been described with particularity, modifications or alterations may be made therein without departing from the spirit and scope of the invention set forth in the appended claims. Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims: An endless drive belt (28) for a vacuum cleaner, the belt (28) including an inner drive surface (30) characterised by a first set of ribs (38) projecting inwardly from the drive surface (30) and extending in a substantially diagonal direction across said surface (30), and a second set of ribs (40) projecting inwardly from the drive surface (30) and extending in a substantially diagonal direction across the drive surface (30) to intersect the first set of ribs (28) to form a diamond pattern on the drive surface (30), wherein the first and second sets of ribs (38,40) define knife-like edges (44) for expelling foreign matter. An endless drive belt according to Claim 1 characterised in that the first and second sets of ribs (38,40) comprise converging tapered portions to define said knife-like edges (44). A vacuum cleaner comprising a drive shaft and a brush roll (22) characterised by an endless drive belt (28) as claimed in Claim 1 or 2 extending around the drive shaft and the brush roll (22) for continuous operation in use. A vacuum cleaner according to Claim 3 further characterised by a housing (14), wherein the brush roll (22) is journalled in the housing (14) for rotation in use about an axis generally parallel to the surface to be cleaned. A vacuum cleaner according to Claim 3 or 4 characterised in that the drive shaft axis is substantially orthogonal to the brush roll (22) axis. A vacuum cleaner according to any of Claims 3 to 5 characterised in that the belt (28) is twisted and in a configuration generally in the shape of a figure 8. A vacuum cleaner according to any of Claims 3 to 6 characterised in that in use the belt (28) is positioned in the path of flowing air to draw foreign particles into a filter bag.

Inventors: LACKNER JOHN R, SCHIAZZA ALFRED, LACKNER, JOHN R., SCHIAZZA, ALFRED
Applicants: SCOTT & FETZER CO, THE SCOTT FETZER COMPANY
Application year: 1993
Main classification: A47L9
IPC codes: F16G1, A47L5, A47L9