Lubricant supply device

A lubricant supply device, which is to be fitted to a nut member engaging with a screw shaft through rolling members to supply lubricant to said screw shaft along with a relative rotational motion of said nut member to said screw shaft and comprising:

• a single elongated application member disposed in a single position on a periphery of said screw shaft so as to extend with its length disposed in a longitudinal direction of said screw shaft along a straight line parallel with a central axial line of said screw shaft, for applying the lubricant on at least one rolling-member running surface of said screw shaft, said application member having at least one tongue portion, which is capable of coming into contact with said at least one rolling-member running surface of said screw shaft to apply the lubricant thereon;
• a lubricant storage member for supplying the lubricant to said application member;
• and
• a control device for controlling an amount of the lubricant supplied from said lubricant storage member to said application member.