GB389590A - Improvements relating to roller shutters - Google Patents

Abstract

389,590. Preventing fires. MATHER & PLATT, Ltd. and TAYLOR, A., Park Works, Manchester. Dec. 22, 1931, No. 35412. [Class 47 (ii).] Relates to roller shutters of the kind which are adapted to fall under their own weight and in which the operating shaft is normally held against rotation by a clutch connection with a non-rotary part. According to the invention, the clutch connection is maintained by a fusible or frangible link and is released by hand-operated means or by a rupture of the link. Further, a hand-operated device is provided for maintaining the clutch connection in any desired position of the shutter, this device becoming operable only after the rupture of the link. In the form shown, the operating shaft a, Figs. 1 and 3, is actuated by hand-wheels f, g, and is connected through gearing to the shafts c, d, of two shutters. The clutch comprises a part i secured to the shaft a, and a part j slidably mounted on the shaft. Two levers k, m pivoted respectively on pins n, n<1>, are connected to the part and provide the manual means for releasing the clutch connection. The lever k is normally supported by an arm o of a rotatable shaft p, which arm is supported by a spring r which is connected to a fusible link. Upon the rupture of the link, the levers k, m and arm o rotate about their respective fulcrums and thus release the clutch connection. Locking bolts t, u are adapted to support the levers k, m, respectively, in their raised positions, so that the clutch parts can be maintained in engagement in any desired position of the shutter. These bolts are normally prevented from being moved into engagement beneath the levers by two trip members s mounted on opposite ends of the shaft h, and become operable only after the rupture of the fusible link. In a modification, the levers k, m rest normally in a raised position and are depressed by a weighted arm which is released upon the rupture of a fusible link.