Patent GB-191326723-A (GB)
Title: Improvements in Distance Registering Apparatus for use on Ships.
Inventor: CUMMINGS HENRY HAVELOCK
Filed: 1913-11-20
Granted: 1914-12-24
Abstract: 26,723. Cummings, H. H. Nov. 20. Logs.-Hydraulic or pneumatic transmission mechanism is employed for actuating, according to the rotation of the propelling-engines, distance-registering counters situated on the bridge, chart-room, &c. of a vessel, each counter being provided with a rate-changing gear that may be set by means of a scale according to the unit of distance over the ground represented by, say, one hundred revolutions under the existing conditions of current, wind, slip of screw, &c. The transmitting-medium preferably is the water passing from the feedpump 3, Fig. 2, to the boiler, a valve 5, operated through reducing - gear 6, 7, 8 from a suitable engine part 10, alternately connecting a transmission pipe 12 with the pressure pipe 1 and exhaust pipe 13. Each counter A, B, C has transmitting-connexions 18, 19 with the starboard and port engines S, P, for each of which is provided a flexible bronze diaphragm 22, Fig. 6, adapted to make fluid-tight oscillations in a cavity and, through spring-controlled link - work 26, 27, to actuate, by means of other link - work (not shown), a pawl 43, Fig. 3, engaging a ratchet-wheel 49 attached to the unitswheel of a counter 52 ... 57 registering the revolutions of the corresponding engine. Upon the spindles 60, 61, Fig. 11, of these counters, is centrally mounted a worm shaft 62, which may be adjusted by means of a manually rotatable campost 65 and a spring 66 so as to engage one or other of its terminal clutch members 63, 64 with the corresponding counter. Movement is thus communicated by worm-wheel gearing 67, 72, 73 to a roller 75, Fig. 4<a>, adapted to be radially adjustable upon and to drive a friction disk 76, carrying a flange 80 graduated for the units and tens of the corrected or 'log' distance, transfer being effected to a flange 86 bearing the hundreds numerals by means of a pinion 83 upon the spindle of the friction disk engaging an internal gear 84 upon the flange. Fig. 4<a> shows the mounting for the end of the friction-roller spindle, with a screw adjustment 87 for the roller, used when the apparatus is first set. Fig. 1 shows the face of one of the counting- apparatus, comprising reading-apertures 112, 113 for the revolution counters, a sight-opening 81 for the 'log' distance, and an aperture 96 through which a setting-disk 98 for the friction roller is seen, the disk having a milled edge 100 for setting, and link-work being provided for transforming rotation of the disk into axial displacement of the roller spindle. The setting-disk is graduated in revolutions per mile over the ground. The revolution counters may be zeroized by the means shown in Fig. 8. Upon rotating the units-wheel to zero by hand, a finger 162 can slip into a notch therein, when a pivoted frame 152 carrying the transfer pinions 59 is pressed outwards against a spring 156 to disengage the pinions and lock them in recesses 158. The other numeral-wheels are then rotated by hand, a wire or thin rod being passed in succession through apertures 160 in the wheels and end frames to hold the wheels as they are reset. A table 148, for calculating speeds, and memorandum tablets 166 may also be provided on the instrument casing.