Patent ID: 7540731
Filing Date: 2009-06-02
Classification: B29C

Abstract:
1. A longitudinal drawing device for drawing a synthetic film, the longitudinal drawing device comprising: a frame; and drawing cylinders over which the film is drawn from an upstream position to a downstream position, the drawing cylinders including: a first drawing cylinder that rotates about a first axle; a second drawing cylinder that rotates about a second axle, the second axle being offset in a forward direction and in a vertical direction with respect to the first axle; a third drawing cylinder that rotates about a position-adjustable third axle, the third axle being offset in the forward direction and in the vertical direction with respect to the second axle; and a fourth drawing cylinder that rotates about a fourth axle, the fourth axle being offset in the forward direction and in the vertical direction with respect to the third axle; the longitudinal drawing device further comprising: a first press element, a second press element, and a third press element corresponding to the second drawing cylinder, the third drawing cylinder, and the fourth drawing cylinder, respectively; a motorized rotational drive means for rotationally driving at least two of the cylinders at differentiated speeds so as to form a first drawing stage between the second drawing cylinder and the third drawing cylinder and a second drawing stage between the third drawing cylinder and the fourth drawing cylinder such that the film is drawn on an upstream and a downstream side of the third cylinder; a mobile coupling on which the third drawing cylinder is mounted and that supports the second press element, and a motorized means for causing the mobile coupling to pivot about an axis connected to the frame of the drawing device so as to adjust a position of the third axle and thereby regulate a drawing distance in the first drawing stage formed between the second drawing cylinder and the third drawing cylinder, wherein the second press element accompanies the third drawing cylinder as the position of the third axle is adjusted and the drawing distance in the first drawing stage is regulated.