Tennant Company

Keith N Krier

Neil F Brown

Steven J Waldhauser

Donald J Haub

Richard A Mason

Raymond C Hawkins

Howard N Seim

Neil T Brown

Ranjan K Nirgude

An improvement for electrically driven floor maintenance apparatus including means for varying the speed of the driving motors is disclosed. Two speed ranges are provided by switching means which change the interconnection of the drive motors from series for the low speed range, and parallel for the high speed range. Within each speed range, intermediate speeds are provided by placing resistors with shunt in series with the motors. Time delay circuitry is also included to prevent immediate operation of the vehicle in the high speed of each range until the vehicle has had some time to accelerate. Additionally, means are provided for detecting whether a vehicle is rolling in a forward or reverse direction and circuits are provided to prevent the operator from driving the vehicle in an opposite direction until the vehicle has slowed down to a near stop. A deadman control is provided to prevent the energizing of the drive motors when the operator is no longer seated on the driver's seat. ///

Multi-speed drive with forward/reverse lockout

A scrubbing device is provided including a body which is supported on a plurality of wheels which are driven by a hydraulic pump. The scrubbing machine has a squeegee which is hydraulically raised and lowered. The machine is provided with a sensing device adjacent the hydraulic drive pump which senses the flow of the hydraulic fluid and actuates valving to raise the squeegee upon reverse movement of the scrubber and lower the squeegee upon forward movement of the scrubber.

Scrubber with hydraulic squeegee lift

An improvement for floor maintenance equipment employing electrically driven scrubbing or polishing brushes including means for varying the speed of the brush motors. Two brush speeds are provided by switching apparatus which change the interconnection of the brush motors from series to parallel and from parallel to series. This results in a substantial change in motor speed and power.

Multi-speed brush control

A mobile sweeping machine having separate hydraulic motors for driving a main brush, a propulsion wheel, and a curb brush and a suction blower; a constant speed power source that through a mechanical drive connection drive two variable speed displacement pumps and a fixed displacement pump; one of the variable displacement pumps being fluidly connected to the propulsion wheel motor; the other variable displacement pump being fluidly connected to the main brush motor; and the fixed displacement pump being fluidly connected to a valve for operating the cylinder for varying the downward pressure on the main brush, and to a valve for selectively applying fluid to the cylinder for operating the sweeper hopper, and supplying fluid to drive the curb brush and suction blower motors. A manual control is provided for operating the main brush hydraulic motor to discontinue the rotation of the main brush, to drive the main brush at a low brush speed, and to drive the main brush at a high brush speed. Brush tuft mounting annular flanges are tack welded to a brush tube at spaced locations around the inner peripheries of the flanges which are axially spaced from one another on the brush tube.

Surface maintenance machine drive and brush

A scrubbing machine that includes an articulated vehicle having a power unit and a trailer unit coupled thereto, said trailer unit having cleaning and dirty solution tanks thereon, a squeegee assembly on the power unit having a central liquid take-up tube and a second take-up tube at one end portion thereof, controls operated by turning the vehicle in the appropriate direction for switching the application of vacuum from the central tube to the second tube, a scrubber head unit and an assembly for mounting and carrying the scrubber unit on the vehicle and raising and lowering the scrubber unit including an articulated joint to permit limited pivotal movement of the scrubber head about a generally vertical axis and an axis perpendicular thereto.

Growing community of inventors

Tonka Bay, MN, United States of America

Keith N Krier