Abstract: Two different pile heights (a, b) can be selectively formed during the weaving of terry fabric on a loom by shifting the fabric with its actual beat-up line (10a) back and forth relative to a base beat-up line (3). First and second fabric shifting oscillating motions are performed by first and second power or motion transmission couplings (4, 11) driven through eccentric drives (5, 12) from a main loom drive shaft (DS) and controlled through valves by a central loom control (22) in such a way that a second oscillation with a different amplitude is superimposed on a first oscillation between beat-up groups of weft beat-up motions including partial weft beat-ups and a full weft beat-up motion of a reed (2) in the loom. Different oscillation amplitudes cause a beat-up line shift of different length (a or b) whereby different pile heights are formed.

Abstract: In a method for controlling the pile warp thread tension in weaving terry cloth webs, a thread tension is applied to the pile warp by the spanner beam during partial beat-up operations. The tension is removed or reduced in a controlled manner during each full beat-up motion of the weaving reed and is then reapplied in a controlled manner after the binding-in or interlacing of each pile loop row. An apparatus for carrying out the method includes a spanner beam (7) carried on the free ends of swing arms (6) of which the other ends are rotationally mounted on a supporting shaft (8). A pushing force element is operatively connected to at least one of the swing arms (6) to push the swing arm and therewith the spanner beam in one swinging direction and thereby apply a bias thread tension to the pile warp (4).