[1540]. Irregular gear.

[1541]. Internal or epicycloidal gear. See [Nos. 550] and [1545].

Used for differential blocks, &c. Note that both wheel and pinion run in the same direction, and that more teeth are in gear at one time than with external gear as [No. 1527].

[Larger plate.]

[1542] & [1543]. Varieties of “mangle” gear. The pinion being revolved continuously in one direction produces a reciprocating motion of the wheel; the pinion shaft travels from inside the wheel to outside, and vice versâ, by rising and falling in the slot in the frame. See also [No. 423].

[1544]. Differential gear. See [Section 31]. One wheel has one or more teeth more than the other; used for counters, &c.

[1545]. Moore’s patent differential epicycloidal gear. The pinion and wheel are loose on the shaft and eccentric. One wheel has one tooth more than the other.

[1546]. Multiplying bevil gear. A is a fixed wheel, the cross C is keyed to shaft, B loose on ditto, D and E loose on C; then B is driven at a speed greater than the shaft in proportion to the diameters of the gear. See Patent No. 12,696, 1884.

[1547]. Double worm gear, right and left hand threads. Neutralises the end thrust on shaft. A and B may be geared together.