Patent GB-191310070-A (GB)
Title: Improvements in Automatic Starting Devices for Internal Combustion Engines.
Inventor: ROBERTSON THOMAS EDWARD
Filed: 1913-04-29
Granted: 1914-04-29
Abstract: 10,070. Robertson, T. E., [Smithers, H. and Smithers, W.]. April 29. Turning-gear.-A spring 18, Fig. 1, used to turn an internal-combustion engine drives through the shaft 1, one-way clutch 10, chain or spur wheel 9, and appropriate gearing, the engine shaft. The pawls of this clutch, during normal running, are held out of engagement by centrifugal force. It is re-wound by the engine through the wheel 9, which is connected by a clutch to an eccentric 2 whose strap 3 reciprocates a lever 5. This in turn, through an arm 25, oscillates a tube 22 open on its upper side and carrying a screwed spindle 29. A carriage 30 on the spindle, supports a spring-pressed pawl 34, Fig. 5, which cannot move axially on the carriage but has limited rotary movement thereon. The carriage is prevented from rotating by a jaw 32 which engages the sides of the tube 22. As the tube oscillates the pawl engaging ratchet teeth 19 on the shaft 1 winds up the spring, unwinding being prevented by a holding pawl 38 engaging a ratchet-wheel 39. As the shaft rotates, it turns the spindle intermittently through a star-wheel 43 and causes the carriage to move endways, until the pawl 34 rides on a raised cam part 45 on the shaft 1, which causes a projection 46 on the pawl to snap under a projection 47 on a spring and stops winding ; the disengagement of the pawl is thus effected during a retracting movement of the pawl i.e. when it is not in driving engagement with the ratchet-wheel 19. A lever 48, interconnected with the clutch between the wheel 9 and the eccentric, is used to release the holding-pawl 38 to permit the spring 18 to drive. The lever also acts on a rocking shaft 53 normally held in one position by a spring. This shaft carries a plate 57, which, during unwinding, is kept clear of a bell-crank 58 mounted on the pawl 34. When the spring is unwound, the lever 48 is released' and the plate 57 then can act on the bell-crank to lift the spring, which carries the projection 47, and allow the pawl 34 to act on the ratchet teeth 19. A casing surrounds the mechanism, in which oil may be placed. In a modification, the eccentric sheave 7, Fig. 11, and the chain-wheel used to connect to the engine are integral and driving by the spring takes place as before through a one-way clutch. The eccentric strap engages with a lever 15, which carries the spring-pressed, winding pawl 23. The holding pawl 26 and the winding pawl engage with the ratchet 25 suitably connected to the driving- spring. During winding, a pin 28 on the ratchetwheel intermittently turns a star-wheel 29, which through reduction gearing drives a disk having a recess 34. A spring-pressed pawl 35 placed behind the pawl 26 rides on the edge of the disk, until the wind is complete, whereupon it snaps into the recess, a tail on the pawl 35 then engaging a pin on the winding-pawl and holding it out of action. The winding-pawl may be lifted sufficiently to cause a projection 39 on the pawl to pass under a spring snap 40. To allow the driving-spring to work, a spindle 43 is turned. This spindle acts in turn, through a rod 45 on the winding pawl to hold it, through a finger 47 on the pawl 35 to lift it out of the recess 34, and through a cam 49 on the holding- pawl to release the ratchet-wheel. When the engine is started, the spindle is returned by a spring and the rod 45 disconnects the projection 39 from the snap 40. The sprocket-wheel may be connected to the engine through a friction clutch. In a further modification a flat spiral spring is enclosed in and attached at its ends to a two-part barrel 13, 17, Fig. 19. The eccentric driven from the shaft 1 carries the winding-pawl which engages an internal ratchet-wheel 12 on the part 13, this part being prevented from reverse rotation. The holding-pawl acts on a ratchet-wheel 18 in one with the part 13, which is coanected to a sleeve 37 through a one-way clutch. Two disconnecting clutches are provided, one 40, 44 between the sleeve 37 and the engine shift 29, the other 42, 45 between the shafts 1, 29. To start the engine, the lever 48 is moved to first connect the two clutches and then through the pin 51 and spindle 31 lift the holding-pawl. The spring then drives through the sleeve 37. To prevent overwinding, a disk 21 is slowly rotated by intermittent gearing from the part 13 until a recess in the disk comes in line with the winding-pawl. A pawl carried by the ratchetwheel 21 then drops into the recess and covers up the space -between successive ratchet teeth so that the winding-pawl has no effect. To displace the part 13 so that winding can commence, a pawl is carried by the spindle 31, which engages a recess in the part 13, and on part r. turn movement of the lever 48 shifts the part 13. The two part return movement of the lever 48 may be effected by a pedal moving over a segment having suitable stops. The complete return movement of the lever disconnects the clutches 40, 44 and 42, 45. The one-way clutch through which the spring drives the engine and the disconnecting clutch through which the spring is wound may be mounted on the engine shaft, one of the parts of the latter clutch being formed on the chain-wheel on the engine shaft.