Scrubbing machine

Claim 2

In a scrubbing machine, the combination of a power unit having a separate first frame and comprising a drive motor, power drive wheels and steering wheel means mounted for movement along the surface to be scrubbed and a separate scrubbing unit, said scrubbing unit comprising a separate second frame, scrubbing brush means mounted on said second frame, means for applying scrubbing liquid onto the surface in the path of travel of said scrubbing brush means, and link means between said scrubbing unit frame and said power unit frame to mount and support said scrubbing unit with respect to said power unit, for movement over a surface and for lifting and lowering movement with respect to said power unit, said link means including a central lift link and pivotable guide links which permit twisting of said central lift link a limited amount to permit one side of said scrubbing unit to raise higher than the other.

Claim 3

The scrubbing machine of claim 1 and power cylinder means between said central lift link and said power unit, and control means for said power cylinder means, said control means including means to regulate the lifting force exerted by said power cylinder means on said central lift link.

Claim 4

The scrubbing machine of claim 2 and fluid motor means to drive said scrubbing brush means, and means to raise the pressure on said power cylinder means in response to a rise in working pressure on said fluid motor means above a selected level.

Claim 5

A surface scrubbing machine having a frame member, means to move said machine along the surface to be scrubbed, a pair of counterrotating scrubbing brushes rotatably mounted on said frame member about substantially parallel axes substantially transverse to the direction of movement of said scrubbing unit, means to apply a liquid scrubbing material in the path of normal travel of said scrubbing brushes, a trash receptacle adjacent a first one of said brushes, means to direct solid debris and a first portion of the liquid scrubbing material engaged by said brushes over said first one of said brushes into said receptacle, means to cause recirculation of a portion of the liquid scrubbing material picked up by said brushes back onto the surface being scrubbed in the path of travel of said brushes, vacuum means to remove liquid from said receptacle, said vacuum means includes a vacuum source, a first hydraulic motor means driving said vacuum source, and second hydraulic motor means for driving said brushes, a source of fluid under pressure, and control means controlling operation of said first and second hydraulic motor means, a separate power unit, and a scrubbing unit, means to lift said scrubbing unit relative to said power unit comprising a fluid pressure actuated cylinder, bypass means to control fluid pressure on said cylinder, said source of fluid under pressure supplying said bypass means, and flow divider means from said source of fluid under pressure supplying a priority flow of fluid under pressure to said bypass means.

Claim 6

A surface scrubbing machine having a frame member, means to move said machine along the surface to be scrubbed, a pair of counterrotating scrubbing brushes rotatably mounted on said frame member about substantially parallel axes substantially transverse to the direction of movement of said scrubbing unit, means to apply a liquid scrubbing material in the path of normal travel of said scrubbing brushes, a trash receptacle adjacent a first one of said brushes, means to direct solid debris and a first portion of the liquid scrubbing material engaged by said brushes over said first one of said brushes into said receptacle, means to cause recirculation of a portion of the liquid scrubbing material picked up by said brushes back onto the surface being scrubbed in the path of travel of said brushes, vacuum means to remove liquid from said receptacle, said vacuum means includes a vacuum source, a first hydraulic motor means driving said vacuum source, and second hydraulic motor means for driving said brushes, a source of fluid under pressure, and control means controlling operation of said first and second hydraulic motor means, a separate power unit, and a scrubbing unit, means to lift said scrubbing unit relative to said power unit comprising a fluid pressure actuated cylinder, bypass means to control fluid pressure on said cylinder, said source of fluid under pressure supplying said bypass means, and flow divider means from said source of fluid under pressure supplying a priority flow of fluid under pressure to said bypass means.

Claim 7

The apparatus of claim 4 further characterized in that means to lift said scrubbing unit comprises a lift link having a first end portion and a second end portion, first means for pivotally mounting the first end portion on the power unit and second means for pivotally mounting the scrubbing unit on the second end portion.

Claim 8

In a surface maintenance machine, a power unit having a first frame and wheels mounted on the frame for movement along the surface to be cleaned, a separate maintenance unit having a housing, a power driven, rotatable surface engageable maintenance tool rotatably mounted in the housing, said maintenance unit comprising a scrubbing unit having a second rotary maintenance tool mounted in said housing, said tools being mounted in the housing to rotate about parallel transverse axes, and means for distributing scrubbing liquid onto the surface in the path of travel of the maintenance tools, link means between said first frame and the housing to mount and support the maintenance unit with respect to the power unit and permit limited twisting of the maintenance unit to allow one side of the maintenance unit to raise higher than the other, and power means on the first frame and connected to the link means for selectively moving the link means to raise and lower the maintenance unit with reference to the power unit, said power means including a fluid pressure actuated cylinder.

Claim 9

In a surface maintenance machine, a power unit having a first frame and wheels mounted on the frame for movement along the surface to be cleaned, a separate maintenance unit having a housing, a power driven, rotatable surface engageable maintenance tool rotatably mounted in the housing, said maintenance unit comprising a scrubbing unit having a second rotary maintenance tool mounted in said housing, said tools being mounted in the housing to rotate about parallel transverse axes, and means for distributing scrubbing liquid onto the surface in the path of travel of the maintenance tools, link means between said first frame and the housing to mount and support the maintenance unit with respect to the power unit and permit limited twisting of the maintenance unit to allow one side of the maintenance unit to raise higher than the other, and power means on the first frame and connected to the link means for selectively moving the link means to raise and lower the maintenance unit with reference to the power unit, said power means including a fluid pressure actuated cylinder.

Claim 10

In a surface maintenance machine, a power unit having a first frame and wheels mounted on the frame for movement along the surface to be cleaned, a separate scrubbing unit having a housing, a power driven, rotatable surface engageable maintenance tool rotatably mounted in the housing, and means for distributing scrubbing liquid onto the surface in the path of travel of the maintenance tool, link means between said first frame and the housing to mount and support the scrubbing unit with respect to the power unit and permit limited twisting of the scrubbing unit to allow one side of the scrubbing unit to raise higher than the other and power means on the first frame and connected to the link means for selectively moving the link means to raise and lower the scrubbing unit with reference to the power unit.

Claim 11

In a surface maintenance machine, a power unit having a first frame and wheels mounted on the frame for movement along the surface to be cleaned, a separate scrubbing unit having a housing, a power driven, rotatable surface engageable maintenance tool rotatably mounted in the housing, and means for distributing scrubbing liquid onto the surface in the path of travel of the maintenance tool, link means between said first frame and the housing to mount and support the scrubbing unit with respect to the power unit and permit limited twisting of the scrubbing unit to allow one side of the scrubbing unit to raise higher than the other and power means on the first frame and connected to the link means for selectively moving the link means to raise and lower the scrubbing unit with reference to the power unit.

Claim 12

The apparatus of claim 7 further characterized in that the link means comprises a lift link having a first end portion and a second end portion, first means for pivotally mounting the first end portion on the power unit and second means for pivotally mounting the scrubbing unit on the second end portion.