VACUUM CLEANER

• US 3,639,941 A
• Filed: 06/16/1970
• Issued: 02/08/1972
• Est. Priority Date: 06/16/1970
• Status: Expired due to Term

• Current Assignee: Elmer E. Bruning, Warren J. Kirwan
• Original Assignee: Elmer E. Bruning, Warren J. Kirwan
• Inventors: Kirwan, Warren J., Bruning, Elmer E.
• Primary Examiner(s): Roberts, Edward L.
• Assistant Examiner(s): Moore, C. K.
• Application Number:
  US05/046,615
• Time in Patent Office: 602 Days
• Field of Search: 15/355,356,357,358,359,360,368,371,372,389
• US Class Current: 15/372
• CPC Class Codes: A47L 5/30 with driven dust-loosening tools, e.g. rotating brushes

Abstract

A rotary brush for a vacuum cleaner including mounting means for biasing the brush downwardly against the rug through the use of the tension applied by the belt drive from the motor.

Claims

1. In an upright vacuum cleaner of the type having a motordriven cylindrical brush positioned for engagement with the carpet, the improvement comprising a frame mounting an electric motor, said motor having a horizontally disposed output shaft, a rotary brush supported on said frame in parallel spaced relation to said output shaft, a resilient belt drive connecting said shaft in driving relation to said brush, spaced bearings journaling said brush, said bearings being supported for vertical movement relative to said frame, movement of said bearings upwardly causing an increase in tension in said belt whereby said belt biases said brush to its lowermost position with respect to said frame, cam means in said frame for supporting said brush, said cam means including two cam surfaces angled with respect to a plane perpendicular to said belt, said cam surfaces being at opposite ends of said brush, a cam follower supported at each end of said brush to engage one of said cam surfaces, said brush being movable upwardly with said cam means and cam followEr increasing the tension in said belt.

2. The combination of claim 1 wherein said belt drive is closer to one of said cam surfaces than to the other, the cam surface nearest to said belt being angled less with respect to said perpendicular plane to provide an equal camming force at each end of said brush.

3. The combination of claim 1 wherein said brush includes a hub having an elongated axle extending lengthwise therethrough, bearings at each end of said hub journaling said hub with respect to said axle, said cam follower supporting said bearings with respect to said frame.

4. The combination of claim 3 wherein said cam means comprise oval recesses at each end of said brush, said recesses extending at an angle to a plane perpendicular to the center line of said belt, and said cam followers at each end of said axle being received in said recesses.

5. The combination of claim 4 wherein said belt is positioned closer to one cam means than the other, the cam means positioned closest to said belt having its recess extending at less of an angle to said perpendicular than the other than the other recess.

6. An upright vacuum cleaner comprising a housing enclosing a motor drivingly connected to a fan and to a rotary brush, said brush being positioned in the air stream produced by said fan and mounted in a nozzle opening in said housing for engagement with a surface to be cleaned, means mounting said rotary brush for vertical movement with respect to said housing wherein said brush may extend from said nozzle varying amounts, a resilient belt drivingly connecting said motor and said brush, and cam means between said brush and said housing for increasing said belt tension as said brush moves upwardly, said belt biasing said brush to its most downwardly extended position with respect to said nozzle and housing, said cam means including spaced cams on opposite walls of said housing and cam followers slidably engaging said cams and received on the opposite ends of said brush, said cams urging said brush away from said motor and tensioning said belt as said brush is biased upwardly with respect to said housing.

7. The vacuum cleaner of claim 6 wherein said cam followers comprise cup-shaped members received on the ends of a brush supporting axle, brush bearings between said axle and said brush shielded by said cam followers, said cam followers being received in said cams.

8. An upright vacuum cleaner comprising a housing enclosing a motor drivingly connected to a fan and to a rotary brush, said brush being positioned in the airstream produced by said fan and mounted in a nozzle opening in said housing for engagement with a surface to be cleaned, means mounting said rotary brush for vertical movement with respect to said housing wherein said brush may extend from said nozzle varying amounts, a resilient belt drivingly connecting said motor and said brush, and cam means between said brush and said housing for increasing said belt tension as said brush moves upwardly, said belt biasing said brush to its most downwardly extended position with respect to said nozzle and housing, said housing comprises an upper housing member which supports said motor and brush and a lower housing member which forms the bottom wall of said housing, said nozzle opening being formed in said lower housing member, said cam means being clamped in position at the ends of said brush by said upper and lower housing members.