Wet end portion seal member for ball screw, and ball screw employing said seal member

For a ball screw in which a nut and a male-threaded shaft provided with an arcuate continuous groove threadedly engage by way of a multiplicity of steel spheres inserted between the male threads and female threads, the nut being capable of being made to travel forward and backward along the male-threaded shaft, a wet end portion seal member comprising cut pile, wherein

• the end portion seal member is capable of being attached toward a front or toward a back from said nut, and comprises:
• a support frame body arranged at an outside circumference of said male-threaded shaft;
• a base fabric portion, a back surface of which is secured to an inside circumferential surface of said support frame body;
• and
• the cut pile that protrudes in such fashion as to be directed toward said groove from a front surface of said base fabric portion;
• wherein fiber tip portions of said cut pile are bent and made to abut said groove in such fashion as to occlude a gap between said groove and said support frame body;
• a lubricant has been made to be retained in advance and following forward and backward movement in spaces between pile fibers of said cut pile, and
• wherein the cut pile is helically arranged at an inside circumference of the support frame body in such fashion as to oppose the groove for a length corresponding to not less than one rotation of the outside circumference of the male-threaded shaft.