Hybrid magnetically supported carriage transporter

An apparatus (10) for supporting and stretching a film web in a tenter frame, the apparatus (10), arranged in a Cartesian coordinate system, for transporting a carriage (40) along a track (20) in a non-contacting, substantially magnetically drag-free manner, comprising:

• a track (20) having an axis (20A) oriented along a first x-axis direction, and having one or more magnets (24) mounted on the track (20), each track magnet (24) being displaced from the first x-axis directly in a second z-axis direction and having its magnetization vector (24M) oriented in the yz-plane at a predetermined angular direction relative to the y-axis;
• a carriage (40), guided by the track (20), and having one or more magnets (42) mounted on the carriage (40), each carriage magnet (42) having its magnetization vector (42M) oriented in the yz-plane at a predetermined angular direction relative to the second z-axis direction to interact with the one or more track magnets (24), said interaction being magnetically stable in the second z-axis direction and magnetically unstable in a third y-axis direction, the carriage (40) having mounted thereon a clip assembly (150) adapted to grip the film being supported and apply a film-stretching load along the second z-axis direction;
• and
• a passive stabilization means (70) for stabilizing the position of the carriage (40) in the magnetically unstable third y-axis direction by substantially constraining carriage motion to the xz-plane without inducing mechanical friction or magnetic drag on the carriage (40), so that the carriage (40) may be transported in a stable path along the track (20) without mechanical contact while supporting the applied film-stretching load along the second z-axis direction, the path of the carriage (40) being displaced from the first x-axis direction in the second z-axis direction at a distance corresponding to the magnitude of the applied load.

An apparatus (10) for supporting and stretching a film web in a tenter frame, the apparatus arranged for transporting a carriage (40) along a track (20) in a non-contacting, substantially magnetically drag-free manner, comprising:

• a track (20) having an axis (20A) oriented along a first direction, and having one or more magnets (24) mounted on the track (20), each track magnet (24) having its magnetization vector (24M) oriented in a predetermined direction;
• a carriage (40), guided by the track (20), and having one or more magnets (42) mounted on the carriage (40), each carriage magnet (42) having its magnetization vector (42M) oriented in a predetermined direction to interact with the one or more track magnets (24), said interaction being magnetically stable in a second direction that is orthogonal to the first direction and magnetically unstable in a third direction that is orthogonal to both the magnetically stable second direction and the first direction, the carriage (40) having mounted thereon a clip assembly (150) adapted to grip the film being supported and apply a film-stretching load;
• and
• a passive stabilization means (70) for stabilizing the position of the carriage (40) in the magnetically unstable third direction by substantially constraining carriage motion to a plane orthogonal to the magnetically unstable third direction without inducing mechanical friction or magnetic drag on the carriage (40), so that the carriage (40) may be transported in a stable path along the track (20) without mechanical contact while supporting the applied film-stretching load, the path of the carriage (40) being displaced from the first direction in a direction and at a distance corresponding to the direction and magnitude of the applied load.

An apparatus (10) for supporting and stretching a film web in a tenter frame, the apparatus arranged for transporting a carriage (40) along a track (20) in a non-contacting, substantially magnetically drag-free manner, comprising:

• a track (20) having a first track element (22) oriented along a first axis and a second track element (22) oriented along a second axis, the first and second track elements (22) being disposed about a common axis (20A) in a physically juxtaposed manner at a predetermined separation distance, said common axis (20A) being oriented along a first direction, wherein one or more magnets (24) are mounted on each track element, each track magnet (24) having its magnetization vector (24M) oriented in a predetermined direction;
• a carriage (40), guided by the track (20), and having one or more magnets (42) mounted on the carriage (40), each carriage magnet (42) having its magnetization vector (42M) oriented in a predetermined direction to interact with the one or more track magnets (24), said interaction being magnetically stable in a second direction that is orthogonal to the first direction and magnetically unstable in a third direction that is orthogonal to both the magnetically stable second direction and the first direction, the carriage (40) having mounted thereon a clip assembly (150) adapted to grip the film being supported and apply a film-stretching load;
• and
• a passive stabilization (70) means for stabilizing the position of the carriage (40) in the magnetically unstable third direction by substantially constraining carriage motion to a plane orthogonal to the magnetically unstable third direction without inducing mechanical friction or magnetic drag on the carriage (40), so that the carriage (40) may be transported in a stable path along the track (20) without mechanical contact while supporting the applied film-stretching load, the path of the carriage (40) being displaced from the common axis (20A) in a direction and at a distance corresponding to the direction and magnitude of the applied load.