Surface maintenance machine drive

Claim 2

A surface maintenance machine having propulsion and steering wheels, a debris receptacle, lift arm means for carrying the receptacle, piston cylinder means for operating the arm means to lift the receptacle, an auxiliary brush, hydraulic motor first means for driving the propulsion wheel, hydraulic motor second means for driving the auxiliary brush, a reversible variable displacement first pump, a second pump, a constant speed electric motor, mechanical means for drivingly coupling the motor to the pumps to drive the pumps, first and second lines for directly conducting hydraulic fluid under pressure from the first pump to the first motor means and return fluid from the first motor means to the first pump, a sump for containing hydraulic fluid, a third line for conducting fluid from the sump to the second pump, and third means for connecting the second pump to the second motor means and piston cylinder means to selectively apply fluid under pressure thereto and return fluid to the sump.

Claim 3

The apparatus of claim 1 further characterized in that said pumps are tandem pumps having the first pump as a first pump section and the second pump as a second pump section.

Claim 4

The apparatus of claim 1 further characterized in that the third means includes control valve means for selectively controlling the application of fluid under pressure from the second pump to the cylinder means and second motor means, return line means between the sump and the control valve means and second motor means for returning fluid from the control valve means and second motor means to the sump and a filter in the return line means between the control valve means and the sump.

Claim 5

A surface maintenance machine having propulsion and steering wheels, a debris receptacle, lift arm means for carrying the receptacle, piston cylinder means for operating the arm means to lift the receptacle, an auxiliary brush, hydraulic motor first means for driving the propulsion wheel, hydraulic motor second means for driving the auxiliary brush, a variable displacement first pump, a second pump, a constant speed electric motor, mechanical means for drivingly coupling the motor to the pumps to drive the pumps, first and second lines for conducting hydraulic fluid under pressure from the first pump to the first motor means and return fluid from the first motor means to the first pump, a sump for containing hydraulic fluid, a third line for conducting fluid from the sump to the second pump, and third means for connecting the second pump to the second motor means and piston cylinder means to selectively apply fluid under pressure thereto and return fluid to the sump, the third means including a three position control valve having a first, a second, a third and a fourth port, a pressure fourth line for conducting fluid under pressure from the second pump to the second port, a pressure fifth line for fluidly connecting the third port to the second motor means, a pressure sixth line for fluidly connecting the fourth port to the piston cylinder means for applying fluid under pressure thereto, and a return seventh line fluidly connecting the first port to the sump, said control valve including a valve member movable between a first position fluidly connecting the first and second ports, a second position fluidly connecting the first port to the third port and the second port to the fourth port, and a third position fluidly connecting the first port to the fourth port and the third port to the second port.

Claim 6

A surface maintenance machine having propulsion and steering wheels, a debris receptacle, lift arm means for carrying the receptacle, piston cylinder means for operating the arm means to lift the receptacle, an auxiliary brush, hydraulic motor first means for driving the propulsion wheel, hydraulic motor second means for driving the auxiliary brush, a variable displacement first pump, a second pump, a constant speed electric motor, mechanical means for drivingly coupling the motor to the pumps to drive the pumps, first and second lines for conducting hydraulic fluid under pressure from the first pump to the first motor means and return fluid from the first motor means to the first pump, a sump for containing hydraulic fluid, a third line for conducting fluid from the sump to the second pump, and third means for connecting the second pump to the second motor means and piston cylinder means to selectively apply fluid under pressure thereto and return fluid to the sump, the third means including a three position control valve having a first, a second, a third and a fourth port, a pressure fourth line for conducting fluid under pressure from the second pump to the second port, a pressure fifth line for fluidly connecting the third port to the second motor means, a pressure sixth line for fluidly connecting the fourth port to the piston cylinder means for applying fluid under pressure thereto, and a return seventh line fluidly connecting the first port to the sump, said control valve including a valve member movable between a first position fluidly connecting the first and second ports, a second position fluidly connecting the first port to the third port and the second port to the fourth port, and a third position fluidly connecting the first port to the fourth port and the third port to the second port.

Claim 7

The apparatus of claim 4 further characterized in that there is provided a battery, a seat, a seat operated switch, and circuit means for interconnecting the battery, the switch and the motor to permit energizing the motor when the operator sits on the seat.

Claim 8

The apparatus of claim 4 further characterized in that the first pump has internal circuitry forming a part of the return seventh line and that a filter is provided in the seventh line between said internal circuitrY and the first port.

Claim 9

The apparatus of claim 6 further characterized in that the third means includes a return line that fluidly connects the second motor means to the return seventh line between the filter and the second port and a return line that fluidly connects the cylinder means to the sump.

Claim 10

A surface maintenance machine having a frame, propulsion and steering wheels mounted on the frame, a debris receptacle, a brush mounted on the frame for directing material from the surface to be maintained to the receptacle, lift arm means mounted on the frame for carrying the receptacle adjacent the brush and alternately lifting the receptacle, piston cylinder means for operating the arm means to lift the receptacle, a sump, hydraulic motor means for driving the propulsion wheel, a tandem pump having a reversible, overcenter type variable displacement first pump section and a second pump section, a constant speed motor, mechanical means for drivingly coupling the motor to the pump, mechanical means for drivingly connecting the motor to the brush, first and second lines for conducting hydraulic fluid under pressure from the first pump section to the first motor means and return fluid from the first motor means to the first pump section, a third line connected between the sump and the second pump section to supply fluid to the second pump section, and third means for selectively applying fluid under pressure from the second pump section to piston cylinder means and returning fluid to the sump.

Claim 11

A surface maintenance machine having a frame, propulsion and steering wheels mounted on the frame, a debris receptacle, a brush mounted on the frame for directing material from the surface to be maintained to the receptacle, lift arm means mounted on the frame for carrying the receptacle adjacent the brush and alternately lifting the receptacle, piston cylinder means for operating the arm means to lift the receptacle, a sump, hydraulic motor means for driving the propulsion wheel, a tandem pump having a reversible, overcenter type variable displacement first pump section and a second pump section, a constant speed motor, mechanical means for drivingly coupling the motor to the pump, mechanical means for drivingly connecting the motor to the brush, first and second lines for conducting hydraulic fluid under pressure from the first pump section to the first motor means and return fluid from the first motor means to the first pump section, a third line connected between the sump and the second pump section to supply fluid to the second pump section, and third means for selectively applying fluid under pressure from the second pump section to piston cylinder means and returning fluid to the sump.

Claim 12

The apparatus of claim 8 further characterized where the first and second lines conduct fluid directly from the first pump section to the first motor means and directly from the first motor means to the first pump section, and that said first pump section has internal means forming a part of the third means for supplying make-up fluid to that which flows through the first and second lines.

Claim 13

A surface maintenance machine having propulsion and steering wheels, a debris receptacle, lift arm means for carrying the receptacle, piston cylinder means for operating the arm means to lift the receptacle, an auxiliary brush, hydraulic motor first means for driving the propulsion wheel, hydraulic motor second means for driving the auxiliary brush, a variable displacement first pump, a second pump, a constant speed electric motor, mechanical means for drivingly coupling the motor to the pumps to drive the pumps, first and second lines for conducting hydraulic fluid under pressure from the first pump to the first motor means and return fluid from the first motor means to the first pump, the first pump having an internal circuit forming part of the return line means and supplying makeup fluid to the first pump to compensate for loss of fluid in the first motor means and the first pump, a sump for containing hydraulic fluid, a third line for conducting fluid from the sump to the second pump, and third means for connecting the second pump to the second motor means and piston cylinder means to selectively apply fluid under pressure thereto and return fluid to the sump, said third means including control valve means for selectively controlling the application of fluid under pressure form the second pump to the cylinder means and second motor means, return line means between the sump and the control valve means and second motor means for returning fluid from the control valve means and second motor means to the sump and a filter in the return line means between the control valve means and the sump.

Claim 14

A surface maintenance machine having propulsion and steering wheels, a debris receptacle, lift arm means for carrying the receptacle, piston cylinder means for operating the arm means to lift the receptacle, an auxiliary brush, hydraulic motor first means for driving the propulsion wheel, hydraulic motor second means for driving the auxiliary brush, a variable displacement first pump, a second pump, a constant speed electric motor, mechanical means for drivingly coupling the motor to the pumps to drive the pumps, first and second lines for conducting hydraulic fluid under pressure from the first pump to the first motor means and return fluid from the first motor means to the first pump, the first pump having an internal circuit forming part of the return line means and supplying makeup fluid to the first pump to compensate for loss of fluid in the first motor means and the first pump, a sump for containing hydraulic fluid, a third line for conducting fluid from the sump to the second pump, and third means for connecting the second pump to the second motor means and piston cylinder means to selectively apply fluid under pressure thereto and return fluid to the sump, said third means including control valve means for selectively controlling the application of fluid under pressure form the second pump to the cylinder means and second motor means, return line means between the sump and the control valve means and second motor means for returning fluid from the control valve means and second motor means to the sump and a filter in the return line means between the control valve means and the sump.

Claim 15

A surface maintenance machine having a frame, propulsion and steering wheels mounted on the frame, a debris receptacle, a brush mounted on the frame for directing material from the surface to be maintained to the receptacle, lift arm means mounted on the frame for carrying the receptacle adjacent the brush and alternately lifting the receptacle, piston cylinder means for operating the arm means to lift the receptacle, a sump, hydraulic motor means for driving the propulsion wheel, a tandem pump having A variable displacement first pump section and a second pump section, a constant speed electric motor, mechanical means for drivingly coupling the motor to the pump, mechanical means for drivingly connecting the motor to the brush, first and second lines for conducting hydraulic fluid under pressure from the first pump section to the first motor means and return fluid from the first motor means to the first pump section, the first pump section including pump means having internal means forming a part of the third means for supplying makeup fluid to that which flows through the first and second lines, a third line connected between the sump and the second pump section to supply fluid to the second pump section, and third means for selectively applying fluid under pressure from the second pump section to piston cylinder means and returning fluid to the sump, the third means having a line between the cylinder means and the internal means including a filter and a line from the internal means to the sump to return hydraulic fluid to the sump.

Claim 16

A surface maintenance machine having a frame, propulsion and steering wheels mounted on the frame, a debris receptacle, a brush mounted on the frame for directing material from the surface to be maintained to the receptacle, lift arm means mounted on the frame for carrying the receptacle adjacent the brush and alternately lifting the receptacle, piston cylinder means for operating the arm means to lift the receptacle, a sump, hydraulic motor means for driving the propulsion wheel, a tandem pump having A variable displacement first pump section and a second pump section, a constant speed electric motor, mechanical means for drivingly coupling the motor to the pump, mechanical means for drivingly connecting the motor to the brush, first and second lines for conducting hydraulic fluid under pressure from the first pump section to the first motor means and return fluid from the first motor means to the first pump section, the first pump section including pump means having internal means forming a part of the third means for supplying makeup fluid to that which flows through the first and second lines, a third line connected between the sump and the second pump section to supply fluid to the second pump section, and third means for selectively applying fluid under pressure from the second pump section to piston cylinder means and returning fluid to the sump, the third means having a line between the cylinder means and the internal means including a filter and a line from the internal means to the sump to return hydraulic fluid to the sump.

Claim 17

A surface maintenance machine having propulsion and steering wheels, a debris receptacle, lift arm means for carrying the receptacle, piston cylinder means for operating the arm means to lift the receptacle, an auxiliary brush, first hydraulic motor means for driving the propulsion wheel, second hydraulic motor means for driving the auxiliary brush, a tandem pump having a variable displacement first pump section and a second pump section, a constant speed electric motor, mechanical means for drivingly coupling the motor to the pump, first and second lines for conducting hydraulic fluid under pressure from the first pump section to the first motor means and return fluid from the first motor means to the first pump section, a sump for containing hydraulic fluid, a third line for conducting fluid from the sump to the second pump section, third means for connecting the second pump section to the second motor means and piston cylinder means to selectively apply fluid under pressure thereto and return fluid to the sump, a battery, a seat operated switch, a normally opened, manually operated switch and a first relay connected in series with said switches and said battery, and circuit means connected to said battery and motor for energizing the motor upon the relay being energized.

Claim 18

A surface maintenance machine having propulsion and steering wheels, a debris receptacle, lift arm means for carrying the receptacle, piston cylinder means for operating the arm means to lift the receptacle, an auxiliary brush, first hydraulic motor means for driving the propulsion wheel, second hydraulic motor means for driving the auxiliary brush, a tandem pump having a variable displacement first pump section and a second pump section, a constant speed electric motor, mechanical means for drivingly coupling the motor to the pump, first and second lines for conducting hydraulic fluid under pressure from the first pump section to the first motor means and return fluid from the first motor means to the first pump section, a sump for containing hydraulic fluid, a third line for conducting fluid from the sump to the second pump section, third means for connecting the second pump section to the second motor means and piston cylinder means to selectively apply fluid under pressure thereto and return fluid to the sump, a battery, a seat operated switch, a normally opened, manually operated switch and a first relay connected in series with said switches and said battery, and circuit means connected to said battery and motor for energizing the motor upon the relay being energized.

Claim 19

A surface maintenance machine having propulsion and steering wheels, a debris receptacle, lift arm means for carrying the receptacle, piston cylinder means for operating the arm means to lift the receptacle, an auxiliary brush, hydraulic motor first means for driving the propulsion wheel, hydraulic motor second means for driving the auxiliary brush, a reversible variable displacement first pump, a second pump, a constant speed electric motor, mechanical means for drivingly coupling the motor to the pumps to drive the pumps, first and second lines for conducting hydraulic fluid under pressure from the first pump to the first motor means and return fluid from the first motor means to the first pump, a sump for containing hydraulic fluid, a third line for conducting fluid from the sump to the second pump, and third means for connecting the second pump to the second motor means and piston cylinder means to selectively apply fluid under pressure thereto and return fluid to the sump, said first pump having an internal circuit forming part of the return line means and supplying makeup fluid to the first pump to compensate for loss of fluid in the first motor means and the first pump.

Claim 20

A surface maintenance machine having propulsion and steering wheels, a debris receptacle, lift arm means for carrying the receptacle, piston cylinder means for operating the arm means to lift the receptacle, an auxiliary brush, hydraulic motor first means for driving the propulsion wheel, hydraulic motor second means for driving the auxiliary brush, a reversible variable displacement first pump, a second pump, a constant speed electric motor, mechanical means for drivingly coupling the motor to the pumps to drive the pumps, first and second lines for conducting hydraulic fluid under pressure from the first pump to the first motor means and return fluid from the first motor means to the first pump, a sump for containing hydraulic fluid, a third line for conducting fluid from the sump to the second pump, and third means for connecting the second pump to the second motor means and piston cylinder means to selectively apply fluid under pressure thereto and return fluid to the sump, said first pump having an internal circuit forming part of the return line means and supplying makeup fluid to the first pump to compensate for loss of fluid in the first motor means and the first pump.