Patent ID: 6139208
Filing Date: 2000-10-31
Classification: A45D

Abstract:
Lipstick tube (1) comprising a cylindrical tube body (3), provided with a wall with typically vertical grooves (2), inside which a bottom part (9) moves supporting a lipstick and equipped with two pins which pass through the grooves in the tube body, and move along the helical grooves (40) formed on the inside of an external spiral (4) coaxially surrounding the said tube body (3), such that relative movement of rotation between the tube body (3) and the spiral (4) causes axial displacement of the bottom part (9) and consequently the lipstick attached to it, characterized in that:a) the said tube body (3) and the said spiral (4) comprise click-fit means in the axial direction that work together to permanently assemble the said tube body (3) and the said spiral (4),b) the said tube body (3) and/or the said spiral (4) comprise at least radial spacer (7,70,8,80) of thickness E which forms a circumferential linear contact (71,81), at one of their common ends, and the radial dimensions of the said tube body (3) and the said spiral (4), and particularly the thickness E and the difference R.sub.4 -R.sub.3 between the inside radius R.sub.4 of the said spiral (4) and the outside radius R.sub.3 of the said tube body (3), being chosen such that, after click-fitting, a predetermined permanent mutual pressure is exerted between the said tube body (3) and the spiral (4) along said contact (71,81), so as to give a minimum contact surface area between the spiral (4) and the tube body (3) and to obtain a uniform torque of predetermined level in the relative rotation movement between the two elements (3) and (4), without the use of any lubricant wherein, the thickness E.sub.7,8,70,80 of the said adjacent radial spacer is chosen to be greater than the thickness E'.sub.30 of the said part of the said click-fit means, the difference in thickness E-E' being equal to at least 0.025 mm.