Section 77.—SPINDLES AND CENTRES.
(See also [p. 164].)
[2424]. Lathe fast headstock spindle, showing coned journals and adjustments.
[2425]. Attachment of a loose end centre to a shaft, with coned end, which prevents the hole bursting from cross strain on the centre.
[2426]. Hook centre pin, easily disengaged.
[2427]. Stud centre, with washer riveted on or secured by a nut.
[2428]. Ram or trunk piston centre for connecting rod, fastened by an internal nut.
[2429]. Ram or trunk piston centre, screwed into the piston.
[2430]. Ram or trunk piston centre, with a transverse pin passed right through the piston.
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[2431]. Swaying ball centre.
[2432]. Rocking or swaying centre.
[2433]. Rocking or swaying centre.
[2434]. Eyelet centre for two or more levers.
[2435]. Centre pin, with lug and screw, to prevent it from working out.
[2436], [2437] & [2438]. Methods of fitting up connecting rod centres in trunk pistons or rams.
Section 78.—SCREW GEAR, BOLTS, &c.
(See also [p. 168].)
[2439]. Ball head bolt and nut to allow it to draw up out of line.
[2440]. Universal bolt head.
[2441]. Ball joint bolt and nut.
[2442]. Flush head coned bolt.
[2443]. Mutilated screw and nut.
[2444]. Nut lock, by a fixed lug and split pin.
[2445]. Coned bolt for securing and keying two parts of a machine in exact relation.
[2446]. Double-nutted bolt, easily made of round iron.
[2447]. Lever and compound nuts to obtain great leverage on a screw, as in a press; one nut arm is used as a fulcrum by which the lever forces the other round. Stepped pawls are used to prevent the first nut being loosened while moving the second.
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[2448]. Screw gear to operate three worm wheels in the same direction, for chucks, &c.
[2449]. Screwed stay bolt, as a distance stay for boiler plates, &c.
[2450]. Screw eye and handle nut.
[2451]. Anti-friction worm gear. The worm wheel has friction rollers running on pins, which gear with the worm.
[2452]. Staple bolt and washer plate.
[2453]. Fang plate washer for wood.
[2454]. Fang plate washer for wood.
[2455]. Sunk set screw, with differential threads, to draw two plates or pieces together.
[2456]. Taper screw, quickly released.
[2457]. Mutilated screw to slide into a nut having corresponding sections of the thread cut away, and to fix by a partial turn. Used for breech-pieces of cannon.
[2458]. Bolt head, with transverse holes, for a plain “tommy” bar wrench.
[2459]. Backlash nut for a square thread screw.
[2460]. Cap nut.
Screw stopper. See [No. 2544].
[2461]. Slotted nut and set pin for fine adjustment, or for taking up wear.
Lock nuts; usually two nuts are employed, the thickest one outermost. There are many forms of patent nuts designed to prevent loosening by vibration.
Nuts can be cast around a screw in white metal or brass.