摘要 |
839,419. Door checks. YALE & TOWNE MANUFACTURNG CO. Aug. 18, 1958 [Jan. 8, 1958], No. 26438/58. Class 65(1) A resilient member, as shown a gas-filled bag or capsule 65, is provided in an hydraulic door check so that expansion of the liquid sealed in the door check may take place without an appreciable increase of pressure. A spring urged piston 30 is reciprocated by rotation of shaft 20, carrying an arm 19 linked to the door frame, through a rack 32 and pinion on the shaft 20. When the piston closes oil is forced past flats 33, 33a on the piston, through orifices 60, 61 and past flats 57, 59 on an adjustable valve member 52, whence it flows through the bore carrying shaft 20 back to the piston chamber. The bag 65 is provided with external corrugations to provide maximum contact with the liquid. |