is in engagement with a cam section 16a of the jack cam 16 or a nontilting position indicated by broken lines in which the cam butt 9e of the pile jack 9 is out of engagement with the cam section 16a of the jack cam 16 and positioned on the radially inner side of the cam section 16a of the jack cam 16 the butt 8e of the pile sinker 8 is in engagement with the inner surface of the outer guide cam 14 when the pile sinker 8 and the pile jack 9 are at the positions shown in fig7 loops of a ground yarn by and a pile yarn py are held by the needle 3 and the small nib 8a and the large nib 8b of the pile sinker 8 as shown in fig1 in a phase shown in fig8 i e a phase indicated by a sectional view taken on line o b in fig6 the convex cam section 15a of the leveling cam 15 acts on the main butt 9c of the pile jack 9 regardless of the position i e the position indicated by solid lines or the position indicated by broken lines of the pile jack 9 to push the pile jack 9 on the needle cylinder 1 radially outward so that the cam butt 9e.