Gripper carriage and transport assembly for a stretching frame

A traveling-clamp carriage assembly for a web-stretching frame, comprising:

• a generally rectangular guide rail defining one side of said web-stretching frame and lying in a plane generally parallel to a stretching plane of a web of material to be stretched, said guide rail having a first pair of opposite running surfaces generally parallel to said planes and a second pair of opposite running surfaces generally perpendicular to said planes;
• a traveling-clamp carriage displaceable along said rail in a travel direction to stretch said web, said carriage comprising:
• a substantially U-shaped frame having respective shanks straddling said guide rail and disposed respectively above and below said guide rail, and a connecting member bridging said shanks,
• means on said connecting member operable to grip said web,
• a respective first pair of guide rollers on each shank rollingly engaging a respective surface of said first pair of opposite running surfaces, said first guide rollers of one of said shanks being offset in said direction relative to said first guide rollers of said other of said shanks,
• a respective second pair of guide rollers on each shank rollingly engaging a respective surface of said second pair of opposite running surfaces, said second guide rollers of said one of said shanks being offset in said direction relative to said second guide rollers of said other of said shanks, and
• respective coupling means disposed substantially centrally between the surfaces of said second pair on each of said shanks for entrainment of said carriage along said guide rail;
• and
• a transport device displaceable in said direction and engageable with one of said coupling means for entraining said carriage in said direction.