Lash adjuster

A lash adjuster comprising:

• a body formed into a bottomed cylindrical shape;
• a plunger which is inserted into the body so as to be movable up and down and has a bottom wall formed with a valve hole and a peripheral wall standing from an outer periphery of the bottom wall and having an oil passage hole formed therethrough, so that the plunger is formed into a bottomed cylindrical shape, the plunger defining a high-pressure chamber between the bottom wall and the body;
• and
• a partitioning member inserted into the plunger, wherein:
• the partitioning member has a plate-like baffle located opposite the oil passage hole it an inserted state thereof into the plunger, the baffle having an upper end serving as an oil passage end located above the oil passage hole;
• the plunger has an interior divided into two spaces by the baffle, the oil passage hole being located at one space side;
• an oil passage is defined at said one space side;
• and
• a low-pressure chamber is defined at the other space side to store a hydraulic fluid flowing thereinto through the oil passage hole, the oil passage and the oil passage end, the low-pressure chamber supplying the hydraulic fluid through the valve hole into the high-pressure chamber.