Chapter CXXVIII: Section 49: Locking Devices

(_See also p. 110._)

=2266. Lever action for a door, &c.,= to lock it, open or shut, in fixed positions.

=2267. Lever action for a gate= or door, to open or close it and lock it in either position.

=2268. Revolving eyelet= to lock or release a rod or cord.

=2269. Abutment lock.= Can only be opened by revolving the tumbler by a key.

2266.-2269.]

=2270. Secret screw attachment.= The screw is fixed to the back of any article, and fastened to the fixing ~A~ by sliding along the slot. Two, three or four screws and slots are generally used.

=2271. Bolt lock.= The bolt can be released by revolving it 180°.

=2272. Gib-key fastening= for a sliding block or bracket on a plain bar.

=2273. Similar fastening,= using a wooden bar.

=2274. Locking stud,= used for iron bedstead laths.

=2275. Catch and hook.=

=2276. Hinged catch= to lock a screwed gland or nut.

=2277. Letter lock,= or combination lock. Any number of discs may be arranged on a spindle having a feather key, so that they must be all in a certain position to allow the key to slide through a notch or key way cut in each disc, so as to open the loop.

=2278. Locked nut.=

=2279. Spring pawl,= umbrella catch.

=2280. Spring snap,= released by pressing the open ends together.

=2281. Locking pawl= for spur teeth.

=2282. Spring handle.=

=2283. Spring pawl,= locks the wheel against a moderate force, but gives way to a greater force.

=Locked pawl motions.= See Section 62.

=2284. Locking device= for lathe headstock or tool rest. The head of the central pin runs in a ~T~ groove or under the lathe bed, and is clamped by the cone pointed set screw, which bears against a conical recess in the central pin.

=2285. Radius bar,= with notches to lock a hand lever in various positions. The lever may be hinged to lift out of the notches, or made thin enough to spring sufficiently for this purpose.

=2286. Coned screw lock= for a standard foot, pin, or socket and spigot.

=2287. Set screw fixing= for needles, wires, cord, &c.

=2288. Split block to grip a rod,= with handle nut.

=2289. Cam catch= to lock a wheel or spindle.

=2290. Locking gear for a shaft= driven by spur gearing, used in place of a clutch.

=2291. Similar lock for a revolving head,= standard tool post, &c.

=2292. Tee groove for a ~T~ head bolt= for Nos. 2290 and 2291.

=2293. Horse-shoe distance piece= to place between a sliding pinion and the shaft collar to keep it either in or out of gear.

=2294. Wedge plate and screw fastening= for cutters, &c.

=2295. Locking device for a spring lever,= handle, button hook, &c.

=2296. Locked centre pin.=

=2297. Cotter to lock a sliding spindle.=