TAILIEUCHUNG - Five Hundred and Seven Mechanical Movements Episode 3

Tham khảo tài liệu 'five hundred and seven mechanical movements episode 3', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Mechanical Movements. 15 31. Worm or endless screw and a worm-wheel. This effects the same result as 29 and as it is more easily constructed it is oftener used. 32. Friction-wheels. The surfaces of these wheels are made rough so as to bite as much as possible one is sometimes faced with leather or better with vulcanized india-rubber. 33. Elliptical spur-gears. These are used where a rotary motion of varying speed is required and the variation of speed is determined by the relation between the lengths of the major and minor axes of the ellipses. 34. An internally toothed spur-gear and pinion. With ordinary spur-gears such as represented in 24 the direction of rotation is opposite but with the internally toothed gear the two rotate in the same dừection and with the same strength of tooth the gears are capable of transmitting greater force because more teeth are engaged. 35. Variable rotary motion produced by uniform rotary motion. The small spurpinion works in a slot cut ỉn the bar which turns loosely upon the shaft of the elliptical gear. The bearing of the pinion-shaft has applied to it a spring which keeps it engaged the slot in the bar is to allow for the variation of length of radius of the elliptical gear. 36. Mangle-wheel and pinion so called from their application to mangles converts continuous rotary motion of pinion into re- cĩprocatỉng rotary motion of wheel. The j shaft of pinion has a vibratory motion and works in a straight slot cut ỉn the upright stationary bar to allow the pinion to rise and fall and work inside and outside of the gearing of the wheel. The slot cut in the face of the mangle-wheel and following its outline is to receive and guide the pinion-shaft and keep the pinion in gear. 37. Uniform into variable rotary motion. The bevel-wheel or pinion to the left has teeth cut through the whole width of its face. Its teeth work with a spirally arranged series of studs on a conical wheel. 33. A means of converting rotary motion by which the speed