Patent GB-191301199-A (GB)
Title: Improvements in or relating to Speed Indicators.
Inventor: LANDI-NEE-RICCARDI LAURA
IPC: G01P3/10
Filed: 1913-01-15
Granted: 1913-10-23
Abstract: 1199. Landi, [nÚe Riccardi], L. May 15, 1912, [Convention date]. Periodic-counter speed indicators.-An escapement wheel is rotated through an amount proportional to the number of revolutions of the shaft, and this movement is transmitted to a sleeve having helical surfaces adapted to engage an indicating hand or pointer which is set thereby to indicate the speed for a given period of time. The sleeve is operated by electro-magnets, the circuits of which are regulated by an electric motor controlled by a clock. An escapement wheel 1, Fig. 1, mounted on a spindle 2 is controlled by a spring 4, secured at one end to the spindle and at the other end to the casing, and adapted to be wound up by an electric motor 3. The escapementwheel 1 is allowed to rotate step by step by means of an escapement 27, 28 pivoted to the armature 119 of an electro-magnet 23 and actuated thereby. On the upper end of the spindle 2 is loosely mounted a sleeve 8 having helical surfaces with which engage a tooth 10 of a ring 9 secured to a spindle 6 provided with a brake-wheel 11 and an indicating-pointer 12. The wheel 11 is held by a brake or detent 14 and is released at the desired moment by means of a pin 16 on a lever 17, which is rocked when an electro-magnet 19 is energized and which, by means of an insulating-pin 22, breaks the circuit of the magnet 23. The shaft under observation rotates a spindle 43, Fig. 4, on which is mounted a disk 42 having a metal ring 44 with three projections, two of which 45, 46 are shown. Brushes 48, 49 are adapted to rest on the continuous part and the interrupted part respectively, so that the circuit through the brushes is completed three times in one revolution. The brush 48 is connected to the positive pole of the operating-motor, and the brush 49 to the negative pole through the electro-magnet 23 and a switch 33, Fig. 3. The switch comprises an arm 34, on which is mounted a contact 36 adapted, when the teeth of the escapement wheel 1 rock the arm 39, to close the circuit through the contacts 37, 38. A clock is provided to control the opening and closing of the motor circuit, and to ensure that the current through the clock shall be weak, relays are provided. The seconds spindle of the clock has a pinion 76, Fig. 8, with sixty teeth gearing with a pinion 77 of twelve teeth so that the latter pinion rotates once in twelve seconds. A spring contact 84 is carried by the spindle of the pinion 77 and is adapted to engage insulated metal plates 80, 81 for a period of one second. The plates are connected to terminals 87, 88, and thence to the circuits of relays 62, 63, adapted to close the circuit through the electro-magnet 19 and motor 3 respectively. In operation, the rotating ring 44 sends an intermittent current through the electro-magnet 23 to advance the escapement wheel 1. At intervals of ten seconds, the spring contact 84 of the clock completes the circuit through the plate 80, and a relay 62 the armature of which, through its insulated plate 89, depresses spring - controlled rods 91, 92, Fig. 7, and also through corresponding terminals 97, 98 to the wires 128, 129 and a terminal 103 connected to the positive pole of the operating- motor, and through a wire 130 and shunt resistance 101 to a terminal 107 connected to the electro-magnet 19 operating the sleeve. A rod 90, similar to but shorter than the rods 91, 92, is last engaged by the insulated plate 89 to complete the circuit directly through the terminal 107. When the contact 84 breaks this circuit, the rod 90 prevents sparking, and the armature, on rising, completes a circuit through the spring brushes 73, 74 of a switch or contact-breaker 50. The contact 84 then engages the plate 81 and energizes the relay 63, which acts in a manner similar to the above. The armature of the magnet 19 raises the sleeve 8 and frees the brake-wheel 11, and the tooth 10 forces the pointer 12 to rotate to a position indicating the number of revolutions per minute the wheel 11 descends when the circuit is broken and locks the pointer 12 in its set position. The relay 63 operates the motor 3 to bring the escapement-wheel 1 back until a pin 29 thereon meets a stop-pin 30; the switch 33 and contacts 37, 38 are broken until this is accomplished. A second pointer may be provided to indicate the speed at which it is desired to travel so as to enable the operator to see whether the desired speed is maintained.