Patent GB-215753-A (GB)
Title: Improvements in speed indicating apparatus for self-propelled vehicles
IPC: G01P1/10
Filed: 1924-05-06
Abstract: 215,753. Leffler, A. May 8, 1923, [Convention date]. Centrifugal speed indicators with means for indicating particular speeds.-An indicator is set by a speed-responsive device when the vehicle exceeds a predetermined speed and is maintained in set position until it is restored to normal position by gearing driven by the vehicle. When the indicator is restored to normal position, a second indicator is caused to be set thus showing whether the predetermined speed had been exceeded in the previous distance travelled, as well as in the distance being travelled. A shaft 2 driven by the vehicle carries a centrifugal speed-sensitive device 4 connected to a sleeve 7 and has a worm 10 arranged to drive a toothed annulus 15 through gearing 11, 13. Mounted on a shaft 26, which has one end pivoted to a standard 27 and the other end lying in a slot in a bracket 29, are a toothed segment 30, and two indicating segments 32, 33. The segment 30 is adapted to engage with teeth 31 on the annulus 15, but is normally kept out of engagement by a spring-urged lever 36 pivoted at 37. When the speed of the vehicle exceeds a predetermined amount a collar 39 on the governor sleeve 7 moves the end 38 of the lever 36 and allows the segment 30 to fall into engagement with the teeth 31. The segment 32 is rocked into indicating position by a clutch 34, 35, a certain amount of lost motion being introduced so that the vehicle may be run at excessive speed for a predetermined distance without the indicator being set. A spring-urged pawl 42, Fig. 4, enters a notch 41 in the segment 32 and locks it in set position until a predetermined distance has been travelled, when a projection on one of the mileage register wheels 25 engages an arm 54 of the pawl to release the segment. If the speed is not now being exceeded, the indicator will be returned to normal position by a spring 50. In its return a tooth 43 upon it engages a pawl 48, Fig. 5, on the second indicator segment 33 and sets it in the indicating position, thus showing that the predetermined speed had been exceeded in the previous distance interval. A spring-urged pawl 47 is arranged to lock this segment, and to be released periodically by the projection on the wheel of the mileage register before the pawl 42 is released. A stoppin 45 is arranged to limit the movement of the segments. More than two connected indicators 32, 33 may be provided. Provision for non-permanent records.-A number of levers 17 pivoted to the rotary annulus 15 are adapted to be set by the speed-responsive device to provide a temporary record of speeds attained while travelling a predetermined distance. The upper ends of the levers pass through slots 18 in a dial mounted on the annulus 15, and the lower ends are positioned once each revolution by a guide 9 which is adjusted, in accordance with the speed, by the governor sleeve 7. Springs 20 hold the levers in their set positions, a cam 22 being provided to release the springs while the levers are passing through the positioning guide 9. The guide is pivoted at 8 and a restraining spring 23 is connected to a tape which passes over a cam disc 24 carried by the hub of the guide. The dial has graduations 19.