| 摘要 |
PROBLEM TO BE SOLVED: To provide a door closer which enables flow rate adjustment of hydraulic oil to be easily made while utilizing an advantage of a cam type that torque immediately before total closing of a door is large.SOLUTION: A door closer comprises: a main shaft 3 which rotates in accordance with opening/closing operations of a door; main springs 16, 17 for generating closing force; and a buffer piston 10 for flushing away hydraulic oil to a flow rate control flow channel 9 so as to buffer a door closing operation. In the door closer, the main shaft 3 is provided with a cam 12 which elastically deforms the main springs 16, 17 in a door opening operation and receives the closing force of the main springs 16, 17 in the door closing operation, and provided with a rack 21 as a driving part for buffer for moving the buffer piston 10 according to the opening/closing operations of the door separately from the cam 12. Especially, the door closer is suitable for a slide type door closer constituted so that the tip part of an arm which integrally rotates with the main shaft 3 is guided by a rail to slide along the rail. |
