Patent GB-404839-A (GB)
Title: Improvements in and relating to speedometers
IPC: G01P1/07
Filed: 1933-04-13
Abstract: 404,839. Speedometer counting-apparatus. HASLER AKT.-GES. VORM. TELEGRAPHEN-WERKSTATTE VON G. HASLER, 50, Schwarztorstrasse, Berne, Switzerland. April 13, 1933, No. 11061. Convention date, May 28, 1932. [Classes 106 (i) and 106 (iii).] A vehicle speedometer incorporates three counters, one registering the total time of running of the vehicle, one registering the time of running of the vehicle above a certain speed and one registering the number of times that the speed is exceeded, the excess time counter being coupled to the total time counter on the operation of the excess number counter. The total time counter 2 is driven from gearing 5, 6, 7, intermittently operated from the driving shaft O of the speedometer in the manner described in Specification 373,313. The driving wheel 9 of the excess time counter 3 is coupled to the wheel 8 rigid with the wheel 5 by the coupling wheel 33 on a lever 32 secured to a spindle 30 having secured to it a lever 31 actuated by the eccentric 11 at the beginning of the period of excess speed in the manner described below. At the end of the period of excess speed the eccentric is further turned to move the coupling wheel 33 out of engagement with the wheels 8 and 9. The wheel 17 having a head 18 with notch 19 is continuously driven from the driving shaft O of the speedometer through gearing O<11>, 14, 16 and 15. The head 18 forms part of a pawl coupling, the pawl 20 of which is pivoted under a disc 22 about it pin 23 secured to the latter and swings inwardly under the action of a spring 21. The disc 22 is rigidly secured to the spindle 12. A pin 25 projecting upwards from the pawl 20 through a recess 24 of the disc 22 comes within reach of two semi-circular pins 261 and 26<11> of an escapement lever 26 rigidly secured to a vertical spindle 27. The spindle 27 has secured to it a lever 28 engaging with the cam disc 29 with step 29<1> and oblique surface 29<11> and rotated from the spindle of the indicating pointer of the speedometer. When the speed limit is reached the lever 28 will slide on the surface 29<11> to rotate the spindle 27 and the lever 26 and release the pin 25 from the pin 26<11> to allow the tooth 201 of the pawl 20 to engage in the notch 19. The pawl 20, disc 22 and spindle 12 are thus rotated until the pin 25 engages with the pin 261 to disengage the tooth 201 from the notch 19 and stop rotation of the spindle 12. This partial rotation of the spindle 12 causes partial actuation of the counter 4, registering the number of excesses of speed, through the gearing 10 and eccentric 11, and causes, through the eccentric 11, lever 31, spindle 30 and lever 32, the coupling wheel 33 to engage with the wheels 8 and 9 to start the actuation of the excess time counter 3. When the speed falls below the limit the lever 28 rides down the surface 29<11> to rotate the lever 26 and release the pin 25 from the pin 26<11> to allow the tooth 20<1> to engage the notch 19 and rotate the disc 22 and spindle 12 until the pin 25 engages with the pin 261. This further partial rotation of the spindle 12 completes the actuation of the excess number counter 4 and through the eccentric 11 disengages the coupling wheel 33 from the wheels 8 and 9 to stop actuation of the excess time counter 3. Despite the increased driving power required by the excess time counter, the clockwork of the speedometer will not be affected as the drive of the counters is not by the clockwork but by the coupling of the main spring winding device as in Specification 373,313.