Patent GB-190712659-A (GB)
Title: Improvements relating to Electrically Controlled Systems.
Inventor: JULIEN MARIE ADRIEN RIVALS
Filed: 1907-05-31
Abstract: 12,659. Rivals, J. M. A. June 1, 1906, [date applied for under Patents Act, 1901]. Void. [Published under Patents &c. Act, 1907.] Search - lights or other movable apparatus are controlled from a distance by electrical means. The movements of a 'precursor' taking place with little expenditure of energy are caused to produce parallel or proportional movements of bodies subjected to large loads or resistances. The controlling arrangements comprise the 'precursor' a servo-motor, and escapement mechanism, together called the 'propeller,' which is in direct relation with the precursor,' lines leading to one or more distant stations, 'followers,' which are identical in construction with the 'propeller' situated at the respective stations, and an intermediate machine called the 'releaser,' which causes the 'propeller' and all the 'followers' to work synchronously. 'Electric current is obtained from a battery of accumulators or other source. The action of the parts is traced out, beginning from the 'precursor' 1, Fig. 7, which has a cam 3, shown also in Fig. 3, engaging and disengaging a recess in a pinion 5, mounted on a shaft 4, which is carried by a second movable part 2. As the precursor' moves backwards or forwards in a determined path, it produces a rocking movement of the pinion 5, which is weighted so as to remain in each inclined position. The pinion is rigidly connected to a rocking electric switch, Fig. 4, consisting of a piece of ebonite or other insulating material 7 carrying metal strips 8, 9 terminating in contact points of iron or platinum which can dip into mercury cups. The points 12, 12<1> are always immersed in the cups 15, 15<1> connected to the poles.of a battery 16. The remaining cups and points form a reversing switch for reversing current in the circuit 17 each time the switch rocks. The mercury switch may be replaced by a different form, shown in Figs. 7 and 10, which is composed of an ebonite sector 18 having four arc-shaped contacts of copper or platinum 20, 20<1>, 21, 21'let into the periphery, which touch two fixed brushes 25, 25<1> forming the terminals of the circuit 17, and copper rings 23, 23<1> touching the terminals of the battery 16. The current is reversed each time the sector rocks. To avoid an interruption of the current, the brushes 25 are made wider than the mica strip which divides the contacts on the sector. The circuit 17 contains an independently excited electric motor which is mechanically connected, as by gear-wheels, to the member 2 and causes it to follow the direction of movement of the precursor' until the motor is de-energized by the arrival of the switch at its middle position. The parts can then remain mutually at rest. To prevent repeated backward and forward movements, a damping-device is introduced between the motor and the member 2. The motor driving the member 2 and its escapement mechanism constitute the 'propeller' shown in Fig. 11, which is generally analogous in function to a relay. An armature 26 supplied with current from the circuit 17 and lying in a constantly excited field is keyed to a shaft 28. The shaft 28 is prevented from turning continuously by a keyedon escapement-wheel 36, which may have one of the forms shown in Figs. 12 and 13. The escape-. ment anchor 40 is fixed on a shaft 39 which bears a toothed sector 38, Fig. 14, gearing with a sector 37 fixed to a separate motor-armature 27. The armature 27 and the sector 37 'are loose on the shaft 28, and are free to make oscillatory movements of a certain amplitude determined by stops 41 embracing an extension 42. To prevent the armature and anchor from sticking in an intermediate position, use is made of a prismatic piece 43, pressed constantly by a spring against the end of the limit 42. Overbalancing weights may be used for the same purpose. The oscillations are produced by reversals of current in a circuit 34, which feeds the armature 27, and each oscillation allows the armature 26 to turn one step. The step-by-step rotation of the armature 26 may take place in either direction according to the direction of current in the circuit 17. A commutator switch 45 is fixed to the shaft 28, and, as it rotates, sends intermittent positive and negative currents from a local battery 51 into a circuit 53 leading to the distant apparatus. The commutator switch, shown separately in Figs. 15 and 16, is composed of an ebonite disk, copper hubs 45, 46 produced into alternate copper strips 47, 48 let into the edge of the disk, and mica separating-pieces 49, together with two pairs of brushes 50, 52, Fig. 11. The distant apparatus consists of a 'follower' S, Fig. 17, which is exactly similar in construction to the 'propeller' P, and a 'releaser' D, which differs only in having two escapement anchors and two oscillating armatures 27<11>, 27<111> instead of one. The escapement wheel is not released until both armatures rock to the same side. There may be two or any number of 'followers,' each similar to the 'propeller' in construction, and the 'releaser ' is provided with an additional oscillating armature and an additional escapement anchor for each additional follower.' When there are more than two escapement anchors, two or more escapement wheels are used, all keyed together to a rotary commutator 44". The rotary armatures 26, 26', 26" of all the machines are in series in the circuit 17 controlled by the rocking reversing-switches shown in Figs. 4 and 10. At any time while the controlling switch occupies one of its inclined positions, the rotary armatures are tending to turn in the same direction. At the middle position of the reversing-switch, the battery is short-circuited through the brushes and the rotary armatures are de-energized. The oscillatory armatures 27, 27<1>, and those of any additional ' followers,' are all connected in series in the circuit 34, which circuit is taken from the brushes of the rotary commutator switch 44<11> of the ' releaser.' The oscillatory armatures of the 'releaser' are fed respectively from the rotary commutator switches 44, 44<1> of the ' propeller' and follower.' The field-windings of all the machines are constantly excited in the same direction and are so arranged with respect to the armature circuits as to get the least self-inductive retarding effect. When the apparatus is started by moving the ' precursor,' the 'releaser' executes its first oscillation on the opposite side to the ' pro- ' peller '; the armature 26<11> makes one step, turning the commutator 44<11>, which sends a reverse current through the oscillatory armatures 27, 27<1>, causing them to rock over to the other side. The armatures 26, 26<1>, released simultaneously, turn one step with their respective commutator switches 44, 44<1>. Both the armatures 27<11>, 27<111> thus receive reversed currents, their escapements are operated, and the armature 26 makes another step with its commutator switch 44<11>. The action proceeds as a succession of synchronous beats of the armatures 27, 271 corresponding synchronous steps of the rotary armatures 26, 26<1> and out of phase' beats and steps on the part of the movable elements of the 'releaser.' The process normally continues until the circuit 17, which contains the rotary armatures, is de-energized, in consequence of the arrival of the 'mover' 2 in such a position relative to the precursor' that the switch shown in Fig. 4 or Fig. 10 comes into the middle or upright position. If the ' precursor' is started in the opposite direction, the current in the circuit 17 will be reversed and the armatures 26, 26', 26" will rotate in the opposite direction, the oscillatory armatures beating as before, but the sign of the ' phase- ' difference' between the ' releaser' armatures and the others being changed. To obviate ' dephasage' or retardation arising when the direction of running is changed, through the back-lash of the various gear-wheels, use is made of shaft-couplings, Figs. 18 and 19, which give a certain amount of free play and thus introduce a compensating ' dephasage' at a charge of running. The coupling consists of two members 35', 35<11>, one carrying a pin 55, the other a pair of fingers 57, 57<1> embracing the pin. The member 35<11> is provided with a brake, Fig. 21, consisting of a cord 60 of silk, hemp, or steel wound in a circular groove, and carrying weights 62 adjustable up to a table 61, through which the ends of the cord pass. The coupling is introduced as shown between the shaft 28 and the spur-wheel 35, or preferably between the shaft 28 and the escapement wheel 36, Fig. 11. Should one of the machines be stopped before the normal termination of the action, one of the oscillatory armatures 27<11>, 27<111> ceases to beat ; all the machines then stop working simultaneously and, in so doing, signal the stoppage to the other stations. A modified arrangement, designed to allow one of a number of ' followers' at different stations to stop without affecting the others, has a corresponding number of 'secondary precursors' simultaneously driven by a ' propeller' and each forming the starting-point of a complete 'junction' or combination of propeller,' ' follower,' and ' releaser.'