Patents by Inventor Michael L. Blehert

Michael L. Blehert has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6705332
    Abstract: A hard floor surface cleaning apparatus includes an aerator, a rotating scrub medium engaging the hard floor surface, a fluid conveyor, and a fluid recovery device. The aerator is configured to produce a foam-like aerated cleaning liquid from a cleaning liquid. The fluid conveyor is coupled to the aerator and is configured to deliver the aerated cleaning liquid onto the scrub medium. The fluid recovery device is configured to remove soiled solution from the hard floor surface.
    Type: Grant
    Filed: December 23, 2002
    Date of Patent: March 16, 2004
    Assignee: Tennant Company
    Inventors: Bruce F. Field, Bryan L. Christensen, Michael L. Blehert
  • Publication number: 20030070697
    Abstract: A method of cleaning a hard floor surface with a surface maintenance vehicle including the steps of generating a foam-like aerated cleaning liquid, selectively conveying the foam-like aerated cleaning liquid to the hard floor surface and a scrubbing medium operatively coupled to the surface maintenance vehicle, scrubbing the hard floor surface with said rotating scrubbing medium and said foam-like aerated cleaning liquid so as to loosen soil from the hard floor surface leaving behind a soiled solution of cleaning liquid and soil, and removing at least a portion of the soiled solution from the hard floor surface through a fluid recovery device. Additional aspects of the present invention include devices for performing the cleaning method.
    Type: Application
    Filed: December 23, 2002
    Publication date: April 17, 2003
    Inventors: Bruce F. Field, Bryan L. Christensen, Michael L. Blehert
  • Patent number: 6398829
    Abstract: A mobile debris collection machine with an improved filter system includes a chassis, wheels for supporting the chassis, a debris collection device on the chassis, a debris container on the chassis, and a vacuum system on the chassis for moving dust and debris from the debris collector to the container. The vacuum system includes a dust and debris inlet, a vacuum fan, a dust and debris conduit extending from the inlet to a deflector which directs dust and debris from the inlet toward an area adjacent the vacuum chamber which is positioned above the debris container. There is a first filter stage upstream of the vacuum fan and attached thereto for rotation with the fan. There are a plurality of second filter stages, each downstream of the vacuum fan with the air flow from the vacuum fan being generally equally divided between the plurality of second filter stages. There is an air outlet for each second filter stage and a diffuser mounted in connection with each air outlet.
    Type: Grant
    Filed: February 1, 2000
    Date of Patent: June 4, 2002
    Assignee: Tennant Company
    Inventors: Kevin L. Shinler, Michael L. Blehert
  • Patent number: 6389641
    Abstract: A vacuum trash collection vehicle includes a debris container and a source of vacuum on the vehicle. There is a hose connected at one end to the debris container and has the source of vacuum applied thereto. The hose is open at its other end to form a debris collection nozzle. There is a boom for supporting the hose during use as a debris collection device. A vacuum pickup head is carried by the vehicle and there are operator controls for raising and lowering the pickup head. The pickup head has an opening of a size and shape to be connected to the hose nozzle. There is a driver accessible control for moving the hose and boom to utilize the hose nozzle as a debris collection device. The hose may be connected to the pickup head opening and thereby provide vacuum to the pickup head so that it functions as a debris collection device.
    Type: Grant
    Filed: June 15, 1998
    Date of Patent: May 21, 2002
    Assignee: Tennant Company
    Inventors: Steven L. Boomgaarden, Michael L. Blehert, Gregory J. Engel
  • Patent number: 5996172
    Abstract: A vacuum trash collection vehicle includes a debris container and a source of vacuum on the vehicle. There is a hose connected at one end to the debris container and has the source of vacuum applied thereto. The hose is open at its other end to form a debris collection nozzle. There is a boom for supporting the hose during use as a debris collection device. A vacuum pickup head is carried by the vehicle and there are operator controls for raising and lowering the pickup head. The pickup head has an opening of a size and shape to be connected to the hose nozzle. There is a driver accessible control for moving the hose and boom to utilize the hose nozzle as a debris collection device. The hose may be connected to the pickup head opening and thereby provide vacuum to the pickup head so that it functions as a debris collection device.
    Type: Grant
    Filed: June 15, 1998
    Date of Patent: December 7, 1999
    Assignee: Tennant Company
    Inventors: Steven L. Boomgaarden, Michael L. Blehert, Gregory J. Engel
  • Patent number: 5611105
    Abstract: A floor scrubber has four wheels for stable support on the floor. These wheels are attached to the underside of a resilient molded plastic frame so that any vertical movement of any of the wheels is transmitted directly to the frame. The frame is ribbed to be stiff in longitudinal bending, but torsionally the frame is somewhat flexible. The scrubber body, which is attached to the upper side of the frame and is supported by the frame, is also a molded plastic part which is somewhat flexible. The weight of the body and its contents keeps all four wheels on the floor at all times, even when the floor is uneven, by flexing the frame and body as needed. This structural flexibility eliminates any need for an additional means to keep all the wheels on the floor, such as a sprung suspension or a center pivoted axle.
    Type: Grant
    Filed: January 13, 1995
    Date of Patent: March 18, 1997
    Assignee: Tennant Company
    Inventors: Michael L. Blehert, Robert A. Geyer
  • Patent number: 5515568
    Abstract: A floor scrubbing machine uses two parallel cylindrical scrub brushes. Each brush is rotated by a separate drive means, and these are at opposite ends of the brushes. This balances the weight of the drives so the brushes exert a uniform pressure on the floor. The brushes are axially offset enough that each brush extends out as far as the drive means of the other brush, thus permitting the machine to scrub close to a wall on either side. The brushes have a more aggressive bristle fill at their ends which extend out under the drive means, where only one brush is scrubbing the floor, so the appearance of the scrubbed floor is essentially the same where scrubbed by one brush as where scrubbed by two brushes.
    Type: Grant
    Filed: October 3, 1994
    Date of Patent: May 14, 1996
    Assignee: Tennant Company
    Inventors: Warren L. Larson, Michael L. Blehert, Robert A. Geyer, Michael S. Wilmo
  • Patent number: 5483718
    Abstract: A floor scrubbing machine has a chassis mounted on front and rear wheels and a scrub head attached to the front of the chassis by a system of articulated links. Structure is provided for absorbing the kinetic energy of the moving machine in the event that the scrub head strikes a fixed object. On impact the geometry of the linkage system causes the front wheels to be lifted off the floor, thereby quickly lifting considerable weight. Also, a pair of heavy springs stretch, and parts of the chassis deform elastically. By this structure the kinetic energy is absorbed within the machine. No heavy protective shrouds are needed, and a simple flange along the front edge of the scrub head housing provides adequate stiffness.
    Type: Grant
    Filed: October 3, 1994
    Date of Patent: January 16, 1996
    Assignee: Tennant Company
    Inventors: Michael L. Blehert, Robert A. Geyer, Michael S. Wilmo
  • Patent number: 5093955
    Abstract: A combination floor sweeping and scrubbing machine is as compact and maneuverable as an equivalent machine which only sweeps or scrubs, while retaining typical hopper and tank volumes. Its operator can change it from sweeping to scrubbing or vice versa at any time by moving a few controls and without adding or removing any parts. It has one debris hopper and one horizontal cylindrical rotating brush and they function in both the sweeping and scrubbing modes. A vacuum system supplies dust control during sweeping and vacuum pickup of dirty solution during scrubbing. In the scrubbing mode a single tank supplies scrubbing solution and receives dirty solution picked up from the floor.
    Type: Grant
    Filed: August 29, 1990
    Date of Patent: March 10, 1992
    Assignee: Tennant Company
    Inventors: Michael L. Blehert, William J. Sampson
  • Patent number: 4819676
    Abstract: This invention is concerned with a machine and/or system as well as a method of operation and an assembly whereby a sweeping unit may be quickly converted into a scrubbing unit and vice versa. The system is capable of operation either in a sweeping mode or a scrubbing mode and is also adaptable to include a vacuum wand assembly when the unit is to be operated in its sweeping mode.
    Type: Grant
    Filed: January 16, 1986
    Date of Patent: April 11, 1989
    Assignee: Tennant Company
    Inventors: Michael L. Blehert, Archie A. Weidner
  • Patent number: 4580313
    Abstract: A walk behind floor maintenance machine is disclosed including a filter and filter housing that may be pivoted away to permit removal of the debris hopper. The filter may be cleaned by vibrating the filter and filter housing. Dust vibrated from the filter slides into the hopper. The hopper may be manually removed for emptying.
    Type: Grant
    Filed: September 12, 1983
    Date of Patent: April 8, 1986
    Assignee: Tennant Company
    Inventor: Michael L. Blehert
  • Patent number: 4466156
    Abstract: An air flow control mechanism is provided in the debris pick-up head (10) of a sweeper to allow selective sweeping of debris. The pick-up head (10) is provided a center skirt (70) which partitions the head interior into two sweeping chambers, a rearward chamber (74) and a forward chamber (75). A filler piece (76) in the rearward chamber (74) lowers the ceiling of the chamber (74) sufficiently to create an air flow velocity differential between the two chambers. Forced air flow directed into the rearward chamber (74) becomes high-velocity, air flow capable of transporting relatively heavy debris to a suction outlet (66) for removal to a collection hopper (13). The forward chamber (75) has low-velocity air flow therethrough for sweeping relatively lighter debris to the suction outlet (66). The air flow control mechanism is adjustable to allow effective sweeping for various combinations of debris densities and sizes.
    Type: Grant
    Filed: January 19, 1983
    Date of Patent: August 21, 1984
    Assignee: Tennant Company
    Inventor: Michael L. Blehert