Doctor blade cleaning method and apparatus

Claim 2

Means for cleaning a doctor blade positioned in engagement with a rotating structure for the removal of solids from the surface thereof, said cleaning means comprising a cleaning blade extending lengthwise of said doctor blade and means for moving said cleaning blade transversely of said doctor blade through an arcuate path from one position in contact with said doctor blade, over the surface of said doctor blade to a second retracted position extending away from said doctor blade, said cleaning blade includes a fixedly positioned offset end portion extending toward the line of engagement of said doctor blade with said rotating structure when in said one position and said cleaning means includes means for periodically and arcuately moving said cleaning blade from said retracted position to and from said one position and means coupled to said moving means for urging the offset portion of said cleaning blade into pressure contact with said doctor blade.

Claim 3

Means for cleaning a doctor blade according to claim 1 wherein said cleaning blade has an essentially L-shaped cross section having a long leg and a short leg, said moving means comprises an elongated member pivoted for rotary movement, means securing the outer end portion of said long leg to said elongated member with said shorter leg extending in a direction toward the line of contact of said doctor blade with rotating structure when in said one position and spring means urging said cleaning blade into contact with said doctor blade.

Claim 4

Means for cleaning a doctor blade positioned in engagement with a rotating structure for the removal of solids from the surface thereof, said cleaning means comprising a cleaning blade extending lengthwise of said doctor blade and means for moving said cleaning blade transversely of said doctor blade through an arcuate path from one position in contact with said doctor blade, over the surface of said doctor blade to a second retracted position extending away from said doctor blade, said cleaning blade being normally in said retracted position and said cleaning means includes means for periodically and arcuately moving said cleaning blade from said retracted position to and from said one position, a pair of swing arms each pivoted at one end adjoining the edges of said rotating structure, said cleaning blade including means pivotally engaging the other end of each swing arm for rotation of said cleaning blade about the axis defined by said pivots, a torque arm fixedly connected at one end to at least one of said pivoted means and means engaging the other ends of said torque arms for moving said cleaning blade through an arcuate path between said retracted position and said one position.

Claim 5

Means for cleaning a doctor blade positioned in engagement with a rotating structure for the removal of solids from the surface thereof, said cleaning means comprising a cleaning blade extending lengthwise of said doctor blade and means for moving said cleaning blade transversely of said doctor blade through an arcuate path from one position in contact with said doctor blade, over the surface of said doctor blade to a second retracted position extending away from said doctor blade, said cleaning blade being normally in said retracted position and said cleaning means includes means for periodically and arcuately moving said cleaning blade from said retracted position to and from said one position, a pair of swing arms each pivoted at one end adjoining the edges of said rotating structure, said cleaning blade including means pivotally engaging the other end of each swing arm for rotation of said cleaning blade about the axis defined by said pivots, a torque arm fixedly connected at one end to at least one of said pivoted means and means engaging the other ends of said torque arms for moving said cleaning blade through an arcuate path between said retracted position and said one position.

Claim 6

Means for cleaning a doctor blade according to claim 3 including spring means reacting on said swing arms to urge said cleaning blade against said doctor blade during movement from said retracted position to said one position and return to said retracted position.

Claim 7

Means for cleaning a doctor blade according to claim 4 wherein said engaging means comprises fluid actuated cylinder and piston assemblies each connected between one end of the associated swing arm and the other end of the associated torque-arm and wherein said torque arms are angularly positioned relative to said cleaning blade to position said cleaning blade in the retracted position when said pistons are at the outer positions of the stroke.

Claim 8

Means for cleaning a doctor blade according to claim 4 wherein said engaging means comprises fluid actuated cylinder and piston assemblies connected between one end of the associated swing arm and the other end of the associated torque arm and wherein said torque arms are angularly positioned relative to said cleaning blade to position said cleaning blade in the retracted position when said piston is at the innermost position of its stroke.

Claim 9

Means for cleaning a doctor blade according to claim 3 wherein the last said engaging means comprises fluid actuated cylinder and piston assemblies each pivoted at one end at a point spaced from said one end of the associated swing arm and outwardly from said rotating structure and pivoted at the other end to the other end of the associated torque arm.

Claim 12

Means for cleaning a doctor blade positioned in engagement with a rotating structure for the removal of solids from the surface thereof, said cleaning means comprising a cleaning blade extending lengthwise of said doctor blade and means for moving said cleaning blade transversely of said doctor blade through an arcuate path from one position in contact with said doctor blade, over the surface of said doctor blade to a second retracted position extending away from said doctor blade, said cleaning blade being normally in said retracted position and said cleaning means includes means for periodically and arcuately moving said cleaning blade from said retracted position to and from said one position, said cleaning blade having an essentially L-shaped cross section having a long leg and a short leg, said moving means comprises an elongated member pivoted for rotary movement, means securing the outer end portion of said long leg to said elongated member with said shorter leg extending in a direction toward the line of contact of said doctor blade with rotating structure when in said one position and means urging said cleaning blade into contact with said doctor blade, a pair of swing arms each pivoted at one end adjoining the edges of said rotating structure, said cleaning blade including means pivotally engaging the other end of each swing arm for rotation of said cleaning blade about the axis defined by said pivots, a torque arm fixedly connected at one end to at least one of said pivoted means and means engaging the other ends of said torque arms for moving said cleaning blade through an arcuate path between said retracted position and said one position.

Claim 13

Means for cleaning a doctor blade positioned in engagement with a rotating structure for the removal of solids from the surface thereof, said cleaning means comprising a cleaning blade extending lengthwise of said doctor blade and means for moving said cleaning blade transversely of said doctor blade through an arcuate path from one position in contact with said doctor blade, over the surface of said doctor blade to a second retracted position extending away from said doctor blade, said cleaning blade being normally in said retracted position and said cleaning means includes means for periodically and arcuately moving said cleaning blade from said retracted position to and from said one position, said cleaning blade having an essentially L-shaped cross section having a long leg and a short leg, said moving means comprises an elongated member pivoted for rotary movement, means securing the outer end portion of said long leg to said elongated member with said shorter leg extending in a direction toward the line of contact of said doctor blade with rotating structure when in said one position and means urging said cleaning blade into contact with said doctor blade, a pair of swing arms each pivoted at one end adjoining the edges of said rotating structure, said cleaning blade including means pivotally engaging the other end of each swing arm for rotation of said cleaning blade about the axis defined by said pivots, a torque arm fixedly connected at one end to at least one of said pivoted means and means engaging the other ends of said torque arms for moving said cleaning blade through an arcuate path between said retracted position and said one position.