TAILIEUCHUNG - Five Hundred and Seven Mechanical Movements Episode 11

Tham khảo tài liệu 'five hundred and seven mechanical movements episode 11', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Mechanical Movements. 95 385. Contrivance employed ỉn Russia for shutting doors. One pin is fitted to and turns in socket attached to door and the other is similarly attached to frame. I n opening the door pins are brought together and weight is raised. Weight closes door by depressing the joint of the toggle toward a straight line and so widening the space between the pins. 386. Folding library ladder. It is shown open partly open and closed the rounds are pivoted to the side-pieces which are fitted together to form a round pole when closed the rounds shutting up inside. 387. Self-adjusting step-ladder for wharfs at which there are rise and fall of tide. The steps are pivoted at one edge into wooden bars forming string-pieces and their other edge is supported by rods suspended from bars forming hand-rails. The steps remain horizontal whatever position the ladder assumes. 388. Feed-motion of Woodworth s planing machine a smooth supporting roller and a toothed top roller. 389. Lifting-jack operated by an eccentric pawl and ratchet. The upper pawl is a stop. 390. Device for converting oscillating into rotary motion. The semicircular piece A is attached to a lever which works on a fulcrum rt and it has attached to it the ends of two bands c and D which run around two pulleys loose on the shaft of the flywheel B. Band c is open and band D crossed. The pulleys have attached to them pawls which engage with two ratchet-wheels fast on the fly-wheel shaft. One pawl acts on its ratchet-wheel when the piece. A turns one way and the other when the said piece turns the other way. and thus a continuous rotary motion of the shaft is obtained. i 391. Reciprocating into rotary motion. The weighted racks A A1 are pivoted to the end of a piston-rod and pins at the end of the said racks work in fixed guide-grooves b in such manner that one rack operates upon the cog-wheel in ascending and the other in descending and so continuous rotary motion is produced. The elbow lever c and spring