GB519937A - Improvements in or relating to panic bolts or emergency exit fastenings - Google Patents

Abstract

519,937. Panic bolts. ADAMS & SON, Ltd., J., WEBBERLEY, J. A., KELTING, G., and READE, C. Sept. 29, 1938, No. 28351. [Class 44] A panic bolt operated by depression of the crush-bar comprises upper and lower bolts 4 slidably guided in a casing 1 which houses operating mechanism comprising a disc or crossbar 2 pivotally connected at 6 to links 5 pivoted to the bolts at 7. Rotation of bar 2 to withdraw the bolts is effected by a lever pivoted at 17, its outer depending end 12 having trunnions 14 which pivotally engage one end of a right- or left-hand crush-bar 15, its inner end having a recess 10 engaging a pin 9 on the disc or on a lateral arm rigid with bar 2. The other end of the crush-bar, which is cranked as shown, is pivoted in a bracket 16. A catch 22 retains arm 12 in its depressed bolt-release position. When the bolts are shot, links 5 occupy a dead-centre position to prevent withdrawal of the bolts except by the crush-bar. A blade-spring 20 co-operates with arm 11 to prevent accidental movement of the crush-bar from its normal raised position. A modification is described in which withdrawal of the bolts may be effected by an outside handle which can be rendered ineffective by a key-lock. The spindle of the bar 2 extends through the door and carries a disc with a pin co-operating with a mutilated disc rotated by the handle to provide a lost motion connection so that the bolts may be withdrawn by the crushbar although the handle is locked. The lock bolt co-operates with projections on the muti-. lated disc to limit its movement to less than that required to retract the bolts.