Belt tracking apparatus

Claim 2

Apparatus for maintaining the transverse alignment of a moving belt comprising: a plurality of rollers forming a path of movement for said belt, a first steering arm having one end of one of said rollers rotatably mounted therein, a second steering arm having the opposite end of said one of said rollers rotatably mounted therein, means for pivotally mounting said second steering arm with respect to said first steering arm, said pivotally mounting means including: a floating plate with end supports mounted thereon being coupled to a reference frame, a flexural cantilever pivot in each said end support for pivotally supporting said first and second steering arms, a center point arm rotatably mounted on said floating plate at the center point of said arm, the ends of said center point arm being pivotally coupled to said first and second steering arms, sensing means mounted adjacent said path of movement for contacting said belt and detecting the lateral movement thereof, and linkage means coupled to said sensing means for pivoting said center point arm about said center point to move said second steering arm with respect to said first steering arm in response to said detected lateral movement of said belt.

Claim 3

The apparatus as defined in claim 1 wherein the sensing means includes at least one member rotatably mounted on an actuating arm forming part of the linkage means, said member being rotated by contact with the edge of the belt to reduce friction between the belt and the member.

Claim 4

Apparatus for maintaining the transverse alignment of a moving belt member comprising: a plurality of roller members defining a path of travel along which said belt member is advanced, a first support member having one end of one of said roller members rotatably mounted therein, a second support member having the opposite end of said one of said roller members rotatably mounted therein, means for supporting said first and second support members in relative pivotal relationship, said supporting means comprising: a floating plate with a flexural cantilever pivot at each end thereof for pivotally supporting said first and second support members, a center point arm rotatably mounted on said floating plate at the center point of said arm, the ends of said center point arm being operatively coupled to said first and second support members, a ratio arm pivotally mounted on saId floating plate, one end of said ratio arm being operatively coupled to said center point arm for exerting a force thereon to rotate said arm about said center point thereof, means normally biasing said center point arm and thus said first and second support members and the ends of said one of said roller members mounted therein in a direction about said supporting means to produce a transverse movement in a predetermined direction of said belt member in relation to said roller members, means adjacent said path of travel to sense the transverse positioning of said belt member, and means responsive to said sensing means for producing a movement of said first and second support members and the ends of said one of said roller members mounted therein about said supporting means to produce a compensating transverse movement of said belt member, said movement producing means including linkage means coupled to said sensing means for transmitting the transverse movement of said belt member to the other end of said ratio arm.

Claim 5

Apparatus for maintaining the transverse alignment of a moving belt member comprising: a plurality of roller members defining a path of travel along which said belt member is advanced, a first support member having one end of one of said roller members rotatably mounted therein, a second support member having the opposite end of said one of said roller members rotatably mounted therein, means for supporting said first and second support members in relative pivotal relationship, said supporting means comprising: a floating plate with a flexural cantilever pivot at each end thereof for pivotally supporting said first and second support members, a center point arm rotatably mounted on said floating plate at the center point of said arm, the ends of said center point arm being operatively coupled to said first and second support members, a ratio arm pivotally mounted on saId floating plate, one end of said ratio arm being operatively coupled to said center point arm for exerting a force thereon to rotate said arm about said center point thereof, means normally biasing said center point arm and thus said first and second support members and the ends of said one of said roller members mounted therein in a direction about said supporting means to produce a transverse movement in a predetermined direction of said belt member in relation to said roller members, means adjacent said path of travel to sense the transverse positioning of said belt member, and means responsive to said sensing means for producing a movement of said first and second support members and the ends of said one of said roller members mounted therein about said supporting means to produce a compensating transverse movement of said belt member, said movement producing means including linkage means coupled to said sensing means for transmitting the transverse movement of said belt member to the other end of said ratio arm.

Claim 6

Apparatus for maintaining the transverse alignment of a moving belt comprising: a tracking drum adapted to rotate around its longitudinal axis for guiding said belt along its path of movement, a first steering arm having one end of said tracking drum rotatably mounted therein, a second steering arm having the opposite end of said tracking drum rotatably mounted therein, a plate member with first and second end plates thereon for pivotally mounting said first and second steering arms respectively thereto along an axis substantially parallel to the tracking drum axis of rotation, said tracking drum axis and said pivotal axis defining a plane arranged to bisect the angle between the planes of the belt runs on either side of said tracking drum, control means for pivotally actuating said steering arms in opposite directions about a pivotal axis in said bisector plane and normal to the axis of said tracking drum in response to a deviation of the belt from said path of movement, sensing means mounted adjacent said path of movement for contacting said belt and detecting the lateral movement thereof, and linkage means operatively connecting said sensing means and said control means to actuate said control means in response to said detected lateral movement of said belt.

Claim 7

Apparatus for maintaining the transverse alignment of a moving belt comprising: a tracking drum adapted to rotate around its longitudinal axis for guiding said belt along its path of movement, a first steering arm having one end of said tracking drum rotatably mounted therein, a second steering arm having the opposite end of said tracking drum rotatably mounted therein, a plate member with first and second end plates thereon for pivotally mounting said first and second steering arms respectively thereto along an axis substantially parallel to the tracking drum axis of rotation, said tracking drum axis and said pivotal axis defining a plane arranged to bisect the angle between the planes of the belt runs on either side of said tracking drum, control means for pivotally actuating said steering arms in opposite directions about a pivotal axis in said bisector plane and normal to the axis of said tracking drum in response to a deviation of the belt from said path of movement, sensing means mounted adjacent said path of movement for contacting said belt and detecting the lateral movement thereof, and linkage means operatively connecting said sensing means and said control means to actuate said control means in response to said detected lateral movement of said belt.

Claim 8

The apparatus as set forth in claim 4 wherein said control means includes: a center point arm rotatably mounted on said plate member at the center point of said arm, the ends of said center point arm being operatively coupled to said first and second steering arms.

Claim 9

The apparatus as set forth in claim 5 further including: means for normally biasing said control means in a direction about said pivotal axis to produce a center point about which said belt is transversely aligned.

Claim 10

The apparatus as set forth in claim 6 further including: means for operatively coupling said first and second end plates on said plate member to a reference frame, second linkage means operatively coupled to said plate member for effecting a tension force to said belt through said tracking drum, and spring means coupled to said reference frame and said second linkage means for producing said tension force.

Claim 11

The apparatus as set forth in claim 7 further including: crank means for manually operating said second linkage means for selectively applying said tension force to said belt.

Claim 12

The apparatus as set forth in claim 5 wherein said linkage means includes: ratio plate means coupled to said sensing means for transferring the lateral movement detected by said sensing means to a point separated from said sensing means, ratio crank means operatively coupled to said ratio plate means to transfer said lateral movement about a predetermined angle, and ratio arm means operatively coupled to said ratio crank means for further transferring said lateral movement to said center point arm to effect said transversE alignment of said belt.

Claim 13

The apparatus as set forth in claim 1 wherein said linkage means comprises: a ratio plate coupled to said sensing means for receiving the lateral movement of said belt, a ratio arm pivotally mounted on said floating plate for transferring said movement to said center point arm, and means responsive to the transverse movement of said ratio plate to effect said movement of said ratio arm about its pivot point on the floating plate.