US Patent 11610503 Actuator and tripod structure comprising actuator

An actuator includes a cylinder sandwiched between a fixing plate fixed to the other end surface of a supporting plate together with a servomotor and a bearing housing, a ball screw shaft having one end protruding into the cylinder through through holes of the fixing plate, a slide block screwed with one end of the ball screw shaft in the cylinder, a cylindrical-shaped piston coupled to an end of the slide block and reciprocatably located in the cylinder, linear motion bearing units located inside the bearing housing to movably support the piston, and linear motion bearing units located in the cylinder to movably support the slide block.