From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Sprocket and chain dimension data for center guide and side guide type timing chains.
| Identifier | ExFiles\Box 128\3\ scan0147 | |
| Date | 13th April 1934 guessed | |
| SPROCKET and CHAIN DIMENSION DATA CENTER GUIDE TYPE NOMINAL CHAIN WIDTH 3/4 | 1 | 1 1/4 | 1 1/2 | 1 3/4 A: 11/16 | 15/16 | 1 3/16 | 1 7/16 | 1 11/16 B: 3/4 | 1 | 1 1/4 | 1 1/2 | 1 3/4 C: 25/32 | 1 1/32 | 1 9/32 | 1 17/32 | 1 25/32 SIDE GUIDE TYPE NOMINAL CHAIN WIDTH 7/8 | 1 1/8 | 1 3/8 | 1 5/8 A: 7/8 | 1 1/8 | 1 3/8 | 1 5/8 B: 11/16 | 15/16 | 1 3/16 | 1 7/16 C: 5/8 | 7/8 | 1 1/8 | 1 3/8 Diagram Labels: PITCH LINE, A, B, C, OUTSIDE DIAMETER, PITCH DIAMETER, DEPTH OF CUT. Center Guide Type specific labels: .130/.145, .250R, .125/.03125R, .110/.125, .234 Side Guide Type specific labels: B - DISTANCE BETWEEN GUIDE LINKS, .167, .250R .125, .254 Table 1: Pitch and Outside Diameter No. Teeth | Pitch and Outside Diameter 18 | 2.160 19 | 2.278 20 | 2.397 21 | 2.516 22 | 2.635 23 | 2.754 24 | 2.872 25 | 2.992 26 | 3.111 27 | 3.230 28 | 3.349 29 | 3.468 30 | 3.587 31 | 3.707 32 | 3.826 33 | 3.945 34 | 4.064 35 | 4.183 36 | 4.303 37 | 4.422 38 | 4.541 39 | 4.660 40 | 4.780 41 | 4.899 42 | 5.018 43 | 5.137 44 | 5.257 45 | 5.376 46 | 5.495 47 | 5.614 48 | 5.734 49 | 5.853 50 | 5.972 51 | 6.092 52 | 6.211 53 | 6.330 54 | 6.449 55 | 6.569 56 | 6.688 57 | 6.807 NOTE: A tolerance of Plus .000 Minus .010 is allowed on the outside diameter. Table 2: SHAFT CENTER DIMENSIONS 2 TO 1 RATIO - NUMBER OF TEETH IN SPROCKETS Links in Chain | 18-36 | 19-38 | 20-40 | 21-42 | 22-44 | 23-46 | 24-48 | 25-50 | 26-52 | 27-54 | 28-56 46 | 3.391 48 | 3.734 | 3.469 50 | 4.173 | 3.864 52 | 4.560 | 4.254 | 3.943 54 | 4.945 | 4.642 | 4.335 | 4.022 56 | 5.329 | 5.028 | 4.723 | 4.415 | 4.100 58 | 5.711 | 5.412 | 5.110 | 4.804 | 4.494 | 4.179 60 | 6.093 | 5.795 | 5.495 | 5.192 | 4.885 | 4.574 62 | 6.473 | 6.177 | 5.878 | 5.577 | 5.273 | 4.965 | 4.653 64 | 6.853 | 6.558 | 6.261 | 5.962 | 5.659 | 5.354 | 5.045 | 4.731 66 | 7.232 | 6.938 | 6.642 | 6.345 | 6.044 | 5.741 | 5.435 | 5.125 | 4.810 68 | 7.612 | 7.318 | 7.023 | 6.727 | 6.428 | 6.127 | 5.823 | 5.516 | 5.204 | 4.888 70 | | 7.698 | 7.404 | 7.108 | 6.811 | 6.511 | 6.209 | 5.904 | 5.596 | 5.284 72 | | | 7.783 | 7.489 | 7.192 | 6.894 | 6.594 | 6.291 | 5.985 | 5.676 | 5.362 74 | | | | 7.869 | 7.573 | 7.276 | 6.977 | 6.676 | 6.373 | 6.066 | 5.756 76 | | | | | | 7.658 | 7.360 | 7.060 | 6.758 | 6.454 | 6.146 78 | | | | | | | 7.742 | 7.444 | 7.143 | 6.841 | 6.535 80 | | | | | | | | 7.826 | 7.527 | 7.226 | 6.922 82 | | | | | | | | | | 7.610 | 7.308 84 | | | | | | | | | | | 7.693 NOTE: A tolerance of +0 to -.005 is permissible on the above center distances. THE various conditions affecting the successful application of timing chains require almost an equal number of types and sizes to accomplish the best results in each individual application. In order to properly meet this need, the Morse Chain Company offers several special types of chain, embodied in two standard pitches; namely the ½-inch pitch and ⅜-inch pitch found best adapted to engine timing. It is desired to illustrate here, the ⅜-inch pitch type No. 766 chain, and supply the sprocket and chain data, as shown on the opposite page, to aid in the design of a drive. The engaging link form of this chain is a development of the Morse constant pressure angle system of tooth engagement. It is symmetrical in shape, allowing direction of travel either way. The joint construction consists of a solid round pin and semi-bushing. The outer links are set over the pins under pressure and firmly riveted, which prevents them from rotating. The semi-bushing is secured in alternate sections of links and functions with these links. This chain is furnished in either the center or outside guide construction as shown above and is adapted to both the triangular and two sprocket drives. It is also supplied in the duplex type of chain, specially for use with the Morse Automatic Adjustment. | ||