DAMPER

PROBLEM TO BE SOLVED: To put a brake on a moving member, which reciprocates along a shaft center, over a whole stroke area with a brake force having hysteresis characteristics.SOLUTION: A damper 1 has a housing 2 and a brake mechanism 8 housed in the housing 2. The housing 2 has a hollow cylindrical case 3 including a screw part 31 formed on an inner wall 32 enclosing a moving member 9 in a periphery of a shaft center O1. The brake mechanism 8 includes: a rotary screw member 6 which rotates through engagement with the screw part 31 of the case inner wall 32 while moving along the shaft center O1 of the case 3 in conjunction with the moving member 9; friction members 5A, 5B which move with the rotary screw member 6 while causing end surfaces 60 of the rotary screw member 6 and slide surfaces 53 to slide; and an elastic body 4 which is disposed between the friction member 5B and a bottom part 34 of the case 3 and integrally biases the two friction members 5A, 5B and the rotary screw member 6 disposed between the friction members 5A, 5B to a cover 7 side so that the slide surfaces 53 of the two friction members 5A, 5B are pressed to the end surfaces 60 of the rotary screw member 6.SELECTED DRAWING: Figure 7 【課題】軸心に沿って往復移動する移動部材を、ストローク全域に渡って、ヒステリシス特性を有する制動力で制動する。【解決手段】ダンパ１は、ハウジング２、ハウジング２に収容された制動機構８を有する。ハウジング２は、移動部材９を軸心Ｏ１周りに囲む内壁３２にネジ部３１が形成された中空筒状のケース３を有し、制動機構８は、移動部材９に連動してケース３の軸心Ｏ１に沿って移動しながら、ケース内壁３２のネジ部３１とのかみ合いにより回転する回転ネジ部材６と、回転ネジ部材６の端面６０と摺動面５３とを摺動させながら回転ネジ部材６とともに移動する摩擦部材５Ａ、５Ｂと、一方の摩擦部材５Ｂとケース３の底部３４との間に配置され、２枚の摩擦部材５Ａ、５Ｂの摺動面５３が回転ネジ部材６の端面６０に押し当てられるように２枚の摩擦部材５Ａ、５Ｂ及びその間の回転ネジ部材６を一体としてカバー７側に付勢する弾性体４と、を有している。【選択図】図７