Patent GB-260761-A (GB)
Title: An automatic route indicating or recording device for use on motor or other vehicles
IPC: G01C21/14
Filed: 1925-10-27
Abstract: 260,761. Brogden, T. W. E. Oct. 27, 1925. Course-recording apparatus.-In apparatus for use on vehicles, comprising a map &c. and a pointer &c. adapted to be moved relatively to each other by mechanism operated from a moving part of the vehicle and controlled by a compass so that the path of the pointer over the map corresponds to the route taken by the vehicle, the control is effected by a cam carried by the compass needle. The map and pointer are mounted in a casing 1, Figs. 1 and 2, divided into compartments 4, 5, the map 7 being adapted to be unwound between rollers mounted on shafts 6 which are journaled in floating bearings 9 sliding in guides 10 and acted on by compression springs 11 so that the map rolls are always pressed into engagement with a roller 12. A pulley 14 keyed to the end of the roller 12 is engaged by flexible cable 15 passing out through the casing. The pointer 27 is slidably mounted on a non-circular rod 19 and has a projection 20 engaging a screw 21 adapted to be driven by gearing 22, 23 from a pulley 25 around which passes a flexible cable 26 also passing out through the casing. The compass and actuating-means are contained in a casing 29, Fig. 7, divided into compartments 37, 38, the compass needle being mounted on, a pivot 34 and carrying a cam 31 for controlling the movements of the map and pointer; the needle is balanced by a member 35. Corrections for local error are applied by permanent magnets carried by members 32, 33. The compass is surrounded by a sleeve 41 adapted to be reciprocated at a speed proportional to that of the vehicle and carrying at its upper end four flexible tubes 46 - - 49 in which are mounted plungers 50 - - 53 disposed at horizontal angles of 90‹ to each other and adapted to be acted upon by the cam 31, the arrangement being such that when the vehicle is on a cardinal course onlv one plunger is acted upon whilst on an intercardinal course two adjacent plungers are operated. The remote ends of the plungers are pivoted to links 54 - - 57 pivotally mounted on shafts 58, 59 to which are secured drums 61. 62 adapted to be engaged frictionally by pawls 63 - - 66 on the links 54 - - 57. Springs 67 restore the plungers to their normal positions during the upward movement of the sleeve 41. The shaft 58 is connected by gearing 68, 69 to a pulley 71 around which passes the cable 15 actuating the map, and the shaft 59 carries a pulley 72 carrying the cable 26 which actuates the indicator. To reciprocate the sleeve 41, a flexible shaft 73 driven by a moving part of the vehicle carries a worm 74 actuating a worm-wheel 45 having a cam face 75 which operates a bell-crank lever 78, 79 connected by suitable linkage to a lever 84 pivoted to the lower end of the sleeve 41. A reciprocating movement is at the same time imparted to a platform 85 beneath the needle 30 for straightening the latter and for raising it from its bearings when engaged by the plungers; for this purpose the platform is secured to a member 90 which is operated by the arm 79 through links 86, 87, 89. To facili. tate the use of a map of greater width than the map case, the map may be divided into strips joined to. form a continuous roll, automatic means being provided for bringing a fresh strip into position, and at the same time returning the pointer to the opposite side of the map, when the pointer reaches the end of its screw. The said means consist of levers 93, 94 pivoted to the case 1 and connected at their forward ends by a rod 95, their rearward arms being attached to a cable 96 passing out through the case. The levers are adapted to be engaged by a projection 97 on the pointer in either of the extreme positions of the latter. The cable 96 is connected to a lever 107, Fig. 6, pivoted at 108 and adapted to operate a double dog-clutch 98 on the shaft 73 to rotate one of the wheels 99 gearing with a wheel 100 carrying a sprocket 102 which is connected by a chain 106 to sprockets 104, 105 keyed to the shafts 70, 59 carrying the pulleys 71, 72 which are thus rotated to re-adjust the map and pointer. Hand adjustment of the map and pointer may be effected by knobs 16, 28.