| 摘要 |
1,199,257. Toothed gearing; cams. P. G. LEESON. 19 Oct., 1967 [22 Oct., 1966], No. 47484/66. Headings F2Q and F2K. In a speed changing mechanism comprising rollers 2 which are in constant contact with a cam 1 and a recessed track 3, the shape of the recessed track 3 consists of at least two portions defined by either at least two general mathematical formulµ or a general mathematical formula having at least one constant and the same general mathematical formula having at least one different constant, the shape of the cam track being a generation of the shape of the recessed track 3. The cam 1 is secured to an input shaft 7, the recessed track 3 is in a fixed ring 13, and the rollers 2 are guided in an extension 10 of an output shaft 12. A linear motion mechanism, shown in Fig. 9, comprises a rectangular housing 14 having slots 15 out in two opposing sides in which the reduced ends of rollers 16 are free to slide, a recessed track 20 secured to an output member 24, and a cam 17 secured to an input member 19. In another modification, a cam disc 27 is secured to a motor shaft 26, Fig. 11, a recessed track 33 is formed in the motor casing 29, and a disc 31, carrying rollers 33, is attached to an output shaft 32. A compound reduction unit used in the registering device of a gas meter is shown in Fig. 12. In a further modification, slide blocks 53, Fig. 14, carried by a fixed disc 48, support rollers 55 which engage a cam 41 on an input shaft 42, and also support rollers 56 which engage a recessed track 47 in a member 44 secured to an output shaft 45. The rollers may be mounted on pivoted links (64, 66, Fig. 15, not shown). Fig. 16 shows a modification in which rollers 79, 80 are carried by slides 77 supported in radial slots 76 in a fixed disc 74, the rollers 79 engaging a cam 68 secured to a driving shaft 69, and the rollers 80 engaging a recessed track 73 in a flanged member 71 secured to an output shaft 72. A further modification is shown in Fig. 17 in which a continuous roller link chain 86 comprises rollers 86b which are adapted to be moved by a cam 81 into and out of engagement with recesses 86 in a fixed arcuate member 84. |
