116 



HANDBOOK OF MECHANICAL DESIGN 



DOOR AND COVER FASTENINGS 



Finger grooves 



Knob 



"Casi-iron com has o spiral 

 rise of abouf^in.jof file 

 circum ference of Ig in. ouf- 

 sic/e diamefer of cam. Direction 

 of spiral shouidiie such fhaf 

 wifh door hinged on left, 

 knob is fumed ro leff for open- 

 ing door, anci when hinged 

 on fhe right knob is turned 

 right to open door 



Fig. 220. 



'Knob 



I Tapered face ^ 



Adjustable cam, with threaded hole, 

 the spiral being obtained by tapering 

 one face. Nut locks the cam in place 



Fig. 221. 



Lever-type lock. When placed 

 in vertical position, the weight 

 of lever fends fo lock bolt 

 more securely. Tapered 

 brocket furnishes 

 binding action 



Suitable for heavy doors 

 such OS on motors, chain, or 

 belt housings 



„J 



% 



Fig. 222. 



, Knurled ^ 



xl;.jx 



Alternate'' 

 handle, a 

 steel castinq 



Fig. 223 



Plain knob 



Fig. 224.- 

 tener using 

 spring. 



-Snap-type fas- 

 a flat formed 



Lugs hold ■'-■ , 

 spring i. %^ 



control 



Fig. 225. — Snap-type fastener using 

 round wire spring. 



Pressed steel flanged cap with 

 flat lea f spring fastener. A 90-de'i. 

 twist loosens cover Suitable for 

 closing inspection or adjustment 

 openings 



Fig. 226. 



