GB191029213A - Improvements in Saws, especially Endless Chain Saws. - Google Patents

Abstract

29,213. Muir, R. L. Dec. 16. Sawing; tools; diamond tools.-Relates to portable machines for sawing stone &c., of the type in which the teeth are carried by the links of an endless chain passing over a suitable supporting-frame. The machine is mounted on a suitable sledge or carrying-frame 20, and comprises (1) an endless saw 21 such as is described in Specification 17,169/11, and sprocket-wheels 22, 23 carrying the saw and mounted in bearing- members 30, 31, at the ends of a grooved saw frame 32, (2) an arched frame or bow 35 connecting the bearing-members composed of a bent plate 36 reinforced at its edges by longitudinal members 37, (3) a turntable consisting of a fixed base 59 in which is mounted a rotatable baseplate 58 held therein by a removable ring 60, (4) an explosion or other engine 56 mounted on the plate 58 and having its shaft passing through a standard 50 and driving the sprocketwheel 23 through bevel-gearing 61, 62 and friction clutch parts 64, 65, and (5) brackets 40, 47 fixed to a plate 48 rotatably mounted on the engine shaft and carrying the sprocket-wheel shaft 39. The bracket 40 is formed with upwardly-extending arms 41 carrying a pinion 42 engaging an arc-shaped rack on the bearing- member 31, so that by rotating the pinion the saw frame may be elevated about the shaft 39 to any angle. The pinion may be locked in position by a pawl 45 and ratchet-wheel 44. The saw may also be adjusted about the engine shaft so as to cut at any desired angle to the horizontal by means of a pinion 52 gearing with a toothed wheel 51 fixed to the plate 48. The pinion shaft 53 carries a pair of ratchet-wheels 54 having oppositely directed teeth engaged by a double pawl 55 for locking the pinion in position. The sprocket - wheels 22, 23 consist of guide disks 24, 25 and an intermediate sprocket disk 26 riveted together, the sprocket disks being provided with teeth 27 between which fit lugs 28 on the backs of the saw teeth travelling in the groove in the frame 32. Apertures 29 are provided in the guide disks between the sprocket teeth for cleaning purposes. In order to maintain the saw in tension, the sprocket 22 slides in the bearing members 30, and the ends of its shaft 84 are engaged by recesses 83 in the lower ends of a double bell-crank lever 77, on the upper end of which bears an adjustable spring 82. The saw is set in motion by operating a hand-lever 73 connected by a link 72 to a ring - shaped clutch lever 70 engaging a grooved ring 68 on the clutch part 65. Fig. 3 shows a chain saw in which the links are formed with cutter teeth 110 and are connected by rivets 113. Fig. 12 shows another form of saw in which the links have their ends alternately forked and tongued, the forks being provided with key-hole slots 92, 93 and the tongues with circular holes 94 to receive pivot pins 95 having flattened ends. The teeth 96 are secured by rivets 99 in tapering sockets in the links. Fig. 16 shows a further form in which teeth having side plates 101 riveted to them alternate with teeth formed with tongues 103 fitting between the side plates and secured to them by screw pivot pins 105. The tongued teeth have side plates 104 secured to them as filing members. Fig. 18 shows a saw link in which the teeth 107 carry diamonds 108.