US3278931A - Apparatus for the synchronization and relative positioning of two switches - Google Patents

Apparatus for the synchronization and relative positioning of two switches Download PDF

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US3278931A
US3278931A US11483461A US3278931A US 3278931 A US3278931 A US 3278931A US 11483461 A US11483461 A US 11483461A US 3278931 A US3278931 A US 3278931A
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switch
switches
coding
flip
motor
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Lavergne Jean
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Alcatel CIT SA
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P5/00—Arrangements specially adapted for regulating or controlling the speed or torque of two or more electric motors
    • H02P5/46—Arrangements specially adapted for regulating or controlling the speed or torque of two or more electric motors for speed regulation of two or more dynamo-electric motors in relation to one another
    • H02P5/52—Arrangements specially adapted for regulating or controlling the speed or torque of two or more electric motors for speed regulation of two or more dynamo-electric motors in relation to one another additionally providing control of relative angular displacement
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L7/00—Arrangements for synchronising receiver with transmitter
    • H04L7/0095—Arrangements for synchronising receiver with transmitter with mechanical means

Definitions

  • the codingV switch comprises a mechanical switch having a control arm success-ively actuating the contacts of a number of switch housings in the course of a complete revolution made in a period of T seconds.
  • the contacts, N rin number are each closed for a period T, the change of connection by the arm of the switch from one position to another taking place at regular intervals by means of a -rap-idly operating mechanism controlled by the position of a shaft driven by a motor.
  • a mechanism is described in U.S. Patent 3,132,537, dated May 12, 1964.
  • N n magnitudes are coded, i.e. Nn/ T per second.
  • the device for the relative positioning of two coding switches according ⁇ to the invention is characterized by the fact that it comprises two adjusting devices, namely a preliminary or rough adjustment device and a tine or precise adjustment device, 4the preliminary adjustment device determining a relative positioning of the two switches vsuch that the difference from the ideal positioning is less than one switching step, and a ne adjustment device for the positioning ofthe two switches making it possible to alternate the coding times of the two switches with a small residual difference in relation to the regular alternation.
  • the preliminary adjustment device comprises a device for the adjustment of the angular position by analogue voltage incorporated in each switch and a voltage compa-ring device supplying a pulse at the instant when the vdifference between these voltages changes sign.
  • the preliminary adjustmen-t comprises in a rst phase the star-ting of the driving motor of the first coding switch 3,278,931 Patented Oct. l1, 1966 and then, when the difference between the stepped voltage locating the variable p'osition of the rst switch and the constant voltage locating the tixed position of the second switch is reversed, the starting of .the driving motor of the second switch.
  • the position of the shafts driving the arms of .the switches, which shafts carry out a half-revolution in the interval of one step, is located by means of pulses controlling logical ciruits which, if the relative positions of the said pulses reiiects an incorrect positioning, actuate means for slowing down the motor of the switch which is leading the other switch.
  • FIGURE l contains the diagrams of the distribution of the measuring times of the two associated coding switches.
  • FIGURE 2 is a diagram showing the phase relation between the two switches.
  • FIGURE 3 dia-grammatically illustrates the control shafts of the two switches, with their successive positions.
  • FIGURE 4 is a diagram of the fine adjustment device.
  • FIGURE 5 diagrammatically illustrates the two networks of resistances supplying analogue voltages supplying the information regarding the positions o-f the two switches.
  • FIGURES 6 and 7 are diagrams of .the signals supplied by the elements of the preliminary adjustment device.
  • FIGURE Y8 diagrammatically illustrates a constructio-nal form of the apparatus according to the invention.
  • the change of position of the arm is effected by means of a rapidly opera-ting mechanism controlled by the position of a shaft driven through a gear train (l revolution in 800 milliseconds) 'by a motor rotating at a speed of 1500 r.p.m. (f1 revolution in 40 milliseconds). Twice in each revolution, at intervals of 400 milliseconds, the rapidly opera-ting mechanism causes the shaft of the switch to change position.
  • the curves of FIGURE 1 illustrate an ideal distribution of the measuring times of two associated coding switches.
  • the notches m1, n1, ml and n1 embrace the intervals of 400 milliseconds, each allocated to one posi-tion ofthe arm of the switch I.
  • FIGURElb shows at p1, q1, p.lq1, p"1q"1 the dead times during which Ithe measurements are prevented by transient effects.
  • the diagram of FIGURE 1c shows at x1, y1, x'lyl, x1y1 the times utilized by the measurement and the storage.
  • FIGURES 1d, le and lf correspond to the preceding diagrams in the case of the switch II.
  • FIGURE 1f two measuring periods xgyz, x2y'2 at successive positions, represented in the ideal position in which they are staggered by 200 milliseconds in .relation to those of the switch I.
  • t'o is the instant 800 milliseconds after to and if a preliminary adjustment has limited to less than i400 milliseconds the maximum possible dierence between the actual position of the arm of the -Second switch and its ideal position, it is ensured that the instant t2 will necessarily be located in the interval tol.
  • A (FIGURE 2) be the 380-millisecond zone th1, C the 380 ⁇ millisecond zone k1t0, and B the central l0millisecond interval h1k1.
  • the phase relation will be correct and the switches will be synchronised as long as t2 is located in zone B. If t2 is in the zone A, it will be said that the switch I is leading the switch II, and if it is in the zone C, it will be said that it is lagging.
  • the position J1 corresponds successively to m1, m1 the position J'1 to n1, n1, and so on.
  • Zone B is characterised by the change of state of a monostable trigger circuit 'when it receives the pulse at its input at the time t1, and its return to its pri-or state 40 milliseconds later.
  • the instant t2 will be defined by the passage of the reference diameter through the position LV2.
  • the invention provides members by means of which, in accordance with the position of the pulse t2 of the second switch in relation to the intervals A, B, C, defined by the first, it is possible to determine the reduction of the speed of the motor controlling the progress of one or other of the two switches, of the switch II in the zone A and of the switch I in the zone C, or to exert no action in the zone B.
  • FIGURE 4 The logical circuits by means of Iwhich this result can be obtained are illustrated in FIGURE 4. They comprise two logical OR circuits and four logical AND circuits comprising diodes of known type. A11, A1, A2 represent amplifiers receiving at their inputs the pulses supplied at the times to, t1, t2 respectively. BB1 is a bistable flip-flop whose inputs are connected to the outputs of A0, A1. The binary signals set up at the outputs of the said flip-flop will be denoted by a and respectively.
  • BM1 is a flip-flop to the input of which the signal 2 is applied.
  • the negative pulse registered by the signal at the instant t1 changes the normal state of the flip-flop for a period equal to 40 milliseconds, that of the interval B.
  • b being the output signal of BM1
  • we have b l, While in the other z-ones we have 11:0.
  • the output of the amplifier A2 is connected to the input of a monostable flip-flop BMZ whose output signal C represents the value l only at the instant t2 of the pulse.
  • the logical OR circuit and the inverting circuit In supply the output signals representing (a-j-b) and (m) respectively, while the circuits ET1, ET2, ET3, ET4 supply the output signals ac, ca, c(a ⁇ b), dm) respectively.
  • the bistable Hip-flop BBZ1 receives :at its input 0 the signal c(ajb) and at its input 1 the signal dm).
  • the bistable ip-op BBZ2 receives at its input 0 the signal c and at its input 1 the signal ac.
  • c and c(a ⁇ b) represent l.
  • the effect of the signal 1 at the zero input terminals is to apply the zero signal to the output terminals 0 of the two flip-flops. Therefore, no retarding action is exerted on the motors, and this is appropriate for maintaining a correct position.
  • '-I- b represents the binary digit l, which is set up at the output 0 of BBZ1, which results in a reduction of the speed of the first motor, while since c is equal to 1, no acti-on is exerted on the second motor.
  • the principle applied is as follows: At the starting of the motors, the motor associated with the switch I is fed with full power, while the second motor is not fed.
  • the 164 positions of the switch are characterised by voltages varying linearly from the position 1 to the position 164.
  • the arm of the switch II is then stationary and indicates a fixed constant voltage corresponding to its position.
  • the arm of the switch I indicates a stepped voltage. At the instant when these voltages are equal, the switch II i-s set in operation by a comparing device.
  • the precise adjustment device is placed in circuit only about l second after the starting of the second motor so as to enable the latter to reach its full speed.
  • the pulses employed for bringing the arms of the switches into phase are obtained by the travel of a magnetic arm, conforming to the position of the cam-operated mechanism past magnetic heads disposed in the positions marked T and T1 in FIGURE 31 in the case of the first switch, and in the position marked J2 in FIGURE 32 in the case of the second switch.
  • the motors are of the synchronized asynchronous type. Having ample dimensions, these motors remain in step once the synchronization has been effected.
  • the slip of the motor which is to be slowed down is effected by reducing its feed current by the insertion of a set of resistances in series in each phase, which produces the out-of-step condition.
  • the outputs of the flip-flops BBZ1, BBZ2 are connected to the windings of two relays which control switches which effect the series connection of resistances in the feed wires of the motors associated with the switches 1 and 2 respectively.
  • FIGURE 5 shows the two networks of 163 identical resistances R -supplying analogue voltages giving the information regarding the positions of the two switches. These two networks are fed by a common source (of 24 volts in the example given) and the same current flows therethrough.
  • Resistances r1 and r2 are connected to the two networks on the side of the 24-volt terminal, bringing to about 8 volts the voltage difference across the terminals of the networks, while a resistance R/2 is disposed between the terminal 0 and the input of the second network.
  • the voltage difference between two successive positions is %63 volts at the two networks, but owing to the additional resistance R/ 2 the corresponding voltage levels in the two switches are staggered by a half-step (upwards at the second).
  • FIGURE 6 shows at 6a the stepped signals obtained in the case of switches having only four positions in the case of the ideal staggering of the arms.
  • FIGURE 8 av differential amplifier AD (FIGURE 8), the voltage curve at the output of which is that illustrated in FIGURE 6b, which comprises ZOO-millisecond crenulations at regular intervals except at the instant of the return to zero of the analogue voltages which corresponds to a void.
  • FIGURE 8 illustrates the whole apparatus according to the invention in its preferred form.
  • MC1, MC2 represent the two switching motor sets.
  • the first motor is fed by the poles 1, 2, 3 from a threephase voltage source at its terminals 11, 12, 13.
  • the second motor is fed at 31, 32, 33 at the downstream terminals of a general contactor S1.
  • the terminals of the assembly MC1 at which there are set up at the times to and t1 the pulses utilised in the pre- 6 cise adjustment are designated 4 and 5, 6 is the terminal of MC2 at which the pulse is supplied at the time t2, and 7 and 8 are the terminals of MC1 and MC2 at which the analogue voltages giving the position information are set up.
  • the fine adjustment device illustrated in FIGURE 4 is designated 9, of which the outputs 10 and 20 are the output terminals 0 of the ip-fiops BBZ1, BBZ2, which are connected to the negative pole of the feed battery through the windings of relays 14 and 24 which, when their contacts are in the operating position, place the windings of speed reducing contactors 15 and 25 respectively on open circuit between 32 and 33, thus bringing about the insertion of speed reducing resistances 16 and 26 connected to the contact terminals of the contactors 15 and 25 respectively.
  • the terminals 7 and 8 of the motor-switches MC1 and MC2 are connected respectively to the input terminals 7 and 8 of a differential amplifier AD.
  • the crenulated curve 6b represents a discontinuity
  • a pulse is set up at the output 29 of the differential amplifier AD, which pulse, applied to the input 1 of the flip-fiop BB2, changes its state if it is positive (FIGURE 6) and produces the return of the contact of the relay 30 to the inoperative position.
  • the control circuit of the contactor S2 is then closed and remains self-energized, and the second switch motor MC2 is started.
  • this circuit may delay the bringing of the motors to their normal speed, and a resistance-capacitance delay device is therefore provided, which has a time constant of about 1 second.
  • the correct synchronization of the switch motors MC1, MC2 is indicated by the extinction of a red pilot light R and the ignition of a green pilot light V.
  • a bistable ffip-fiop BB3 receives at its input terminal 1 the pulses (t2) about every 800 milliseconds, while its input terminal 0 is connected to the output 29 of the differential amplifier AD.
  • the output 0 of the flip-flop BB3 is connected to the negative feed pole through a delay device 35 and a relay winding 36 whose contact feeds in its inoperative position a green pilot light V and in its operative position a red pilot light R.
  • a positive pulse (t2) applied to the input 1 of the flipflop BB3 has the effect of causing a voltage in the neighbourhood of zero to be set up at the output 0 of BB3, which results in feeding of the winding 36 and causes ig nition of the red pilot light R, while a positive pulse applied to the input 0, coming from 29, changes the state of the flip-flop BB3, and causes a negative voltage to be set up at the output 0 of BB3 and consequently the release of the relay 36 and the ignition of the green pilot light V.
  • the pulse (t2) occurs at the instant when the rapidly operating mechanism of the second switch commences to operate. Therefore, t2 precedes the change of position of the second switch by a period which may vary from 5 to 25 milliseconds depending upon the accuracy of the mechanism.
  • the pulse (t2) is therefore always succeeded by a pulse emanating from the output of the amplier AD at a time interval not exceeding 25 milliseconds (FIG- URE 6d)
  • the delay device 35 prevents the response of the relay 36 during this interval, so that the green pilot light remains continuously alight.
  • the positive pulses at the input of BB3 are set up only once per period of the switches, which period is equal to 65.6 seconds in the case of 164 positions, and it will be seen (FIGURE 7d) that the state of the flip-dop will generally be fixed by the pulses (t2), the positive pulses at the output AD being capable of producing the ignition of the green pilot light only for a period obviously shorter than 800 milliseconds.
  • the contacts 37 and 38 supplied by the speed reducing contactors and 25 during the precise adjustment determine the ignition of an orange pilot light OR, which thus indicates the adjustment periods.
  • Apparatus for the synchronization and relative positioning of two coding switch means comprising:
  • two adjusting means including a preliminary adjusting means operatively connected to said switch means and driving means, and Ia fine-adjusting means for controlling the fine adjustment of the positioning of the two switch means to enable the coding times of the two switch means to alternate with a slight residual diierence in relation to the regular alternation thereof,
  • said preliminary adjusting means for determining a relative positioning of the two switch means such that the difference from the ideal positioning thereof is smaller than one switching step
  • said preliminary adjusting means further including switch position-locating means operable by analogue voltage and voltage comparing means operatively connected with said driving means.
  • said preliminary adjusting means includes locating means operable by an analogue voltage incorporated in each switch means for locating the angular position thereof and voltage-comparing means operable to supply a pulse at the instant of change in sign in the diierence between these voltages, each switch driving means including an electric driving motor, said preliminary adjusting means further including rst means operable in a first phase for starting the driving motor of one of the coding switch means, and second means operable in a second phase for starting the driving motor of the other coding switch means upon reversal of the difference between the stepped voltage loeating the variable position of said one switch means and the constant voltage locating the -other switch means.
  • Apparatus according to claim 2 further comprising speed-reducing means including a speed-reducing contactor for each driving motor, control windings for the speedreducing contactors, and relay means controlled by said line-adjusting means and operatively connected with said control windings.
  • volt- .age comparing means includes a differential amplifier to the input of which are applied the analogue voltages, flipllop means operatively connecte-d to the output of said differential ampliiier, and relay means controlled by said flip-flop means and operable to control the contactor of the motor for the other coding switch means.
  • speed-reducin-g means are operatively associated with the driving motor of each switch means and each switch means has a driving shaft for driving a respective switch arm, said shafts carrying out a half-revolution in the interval of one step, and locating means in said tine-adjusting means for locating the position of said shafts including pulseproducing means for producing pulses of which the relative position reflects the position of the switch means and logical circuit means operatively connected with said pulseproducing means and operable to actuate, in response to a relative position of said pulsesy reilecting an incorrect positioning, the speed-reducing means of the motor driving the then leading switch means.
  • said logical circuit means include binary flip-flop means having inputs and outputs, said outputs being operatively connected with said speed-reducing means, and means operatively connecting said pulse-producing means with said inputs to apply to said inputs at the instant of the reference position pulse supplied by the other switch means, signals depending upon the position of the said last-mentioned pulse.
  • Apparatus according to claim 6, further comprising a synchronism indicator including indicating pilot lamp means, a relay for controlling said lamp means, a bi-stable flip-flop device which receives the reference pulses of the other coding switch means and is operatively connected to the output of said differential amplifier, and a delay device operatively connecting said bi-stable flip-flop device with said relay.
  • each driving means including a motor and .each switch means has a driving shaft for driving ya respective switch arm said shafts carrying out a half-revolution in the interval of one step, and locating means in said tine-adjusting means for locating the position of said shafts including pulseproducing means for producing pulses of which the relative position rellects the position of the switch means and logical circuit means operatively connected with said pulseproducing means and operable to actuate, in response to a relative position of said pulses reecting an incorrect positioning, the speed-reducing means of the motor drivin-g the then leading switch means.
  • Apparatus according to clai-m 8 wherein said logical circuit means include binary flip-op means having inputs and outputs, said outputs being operatively connected with said speed-reducing means, and means operatively connecting said pulse-producing means with said inputs operable to ⁇ apply to said inputs, at the instant of the reference position pulse of the other switch means ⁇ supplied by said pulse-producing means, signals depending upon the position in time of each reference position pulse.
  • said speedreducing means includes a speed-reducing contactor for each driving motor, control windings for the speed-reducing contactors, and relay means controlled by said neadjusting means and operatively connected with said control windings.
  • Apparatus comprising means for producing reference position pulses for each of said switch means
  • said Ifine adjusting means includes a bi-stable flip-flop means having input and output means, the reference position pulses of one switch means being applied to the input means of said bi-stable flip-Hop means, a monostable flip-flop means having input and output means, the reference position pulses of the other switch meansbeing applied to the input means of said monostable flip-flop means, logical circuit means with the inputs thereof connected to said output means for combining in the outputs thereof the signals supplied thereto, and two bi-st-able flip-flop means receiving in the inputs thereof the combination of signals from said logical circuit means and each supplying a current for the control of the contactors for the reduction of the speed of the driving motors for said ⁇ coding switch means.
  • Apparatus according tol claim 4 further comprising a synchronism indicator including indicating pilot lamp means, va relay for controlling said lamp means, .a Ibi-stable Hip-flop device which receives the reference pulses of the other coding switch means and is operatively connected to the output of said differential amplifier, and a delay device operatively connecting said bi-stable ip-op device with said relay.
  • Apparatus for the synchronization and relative positioning of two coding switches comprising two coding switch means effectively providing a plurality of switching steps with the coding times thereof alternating, .two adjusting means operatively connected with said two coding switch means including preliminary adjusting means for determining a relative position of the two switch means such that the difference from the ideal positioning thereof is smaller 4than one switching step, and line-adjusting References Cited by the Examiner UNITED STATES PATENTS 2,534,842 12/1950 Wallace 340-182 X 2,929,941 3/1960 Bobo 307-87 3,005,151 10/1961 Ale 307-87 3,012,229 12/1961 Berman etal 340-187 X NEIL C. READ, Primary Examiner.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Power Engineering (AREA)
  • Control Of Multiple Motors (AREA)
  • Control Of Position Or Direction (AREA)
US11483461 1960-06-29 1961-06-05 Apparatus for the synchronization and relative positioning of two switches Expired - Lifetime US3278931A (en)

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FR831513A FR1269241A (fr) 1960-06-29 1960-06-29 Dispositif de mise en synchronisme et de positionnement relatif de deux commutateurs codeurs

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3383656A (en) * 1962-10-09 1968-05-14 Cit Compagine Ind Des Telecomm Alternate synchronization device for two rotating switches

Citations (4)

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Publication number Priority date Publication date Assignee Title
US2534842A (en) * 1947-10-10 1950-12-19 Panoramic Radio Corp Dual synchrometric system
US2929941A (en) * 1956-06-15 1960-03-22 Westinghouse Electric Corp Phase and frequency matching regulator for generators
US3005151A (en) * 1957-02-26 1961-10-17 Gilfillan Bros Inc Phase meter
US3012229A (en) * 1957-08-05 1961-12-05 United Aircraft Corp Pulse synchronous system

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Publication number Priority date Publication date Assignee Title
DE1068035B (de) * 1959-10-29 Siemens-Schuckertwerke Aktiengesellschaft, Berlin Und Erlangen Anordnung zur Drehzahlregelung von motorisch angetriebenen Teilen auf konstante Drehzahl- oder Geschwindigkeitsverhältnisse, insbesondere für Mehrmotorenantriebe
DE656252C (de) * 1935-08-01 1938-02-01 Max Levy G M B H Dr Anordnung zur Erzielung des Gleichlaufes von Mehrphasensynchronmotoren in bestimmterRelativstellung der Laeufer
DE950336C (de) * 1955-01-04 1956-10-04 Licentia Gmbh Elektrisches Differential
GB842340A (en) * 1956-07-09 1960-07-27 Standard Telephones Cables Ltd Synchronisation of rotating elements
DE1057869B (de) * 1957-10-18 1959-05-21 Siemens Ag Anordnung zum Synchronisieren eines Filmprojektors mit einem Tonbandgeraet

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2534842A (en) * 1947-10-10 1950-12-19 Panoramic Radio Corp Dual synchrometric system
US2929941A (en) * 1956-06-15 1960-03-22 Westinghouse Electric Corp Phase and frequency matching regulator for generators
US3005151A (en) * 1957-02-26 1961-10-17 Gilfillan Bros Inc Phase meter
US3012229A (en) * 1957-08-05 1961-12-05 United Aircraft Corp Pulse synchronous system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3383656A (en) * 1962-10-09 1968-05-14 Cit Compagine Ind Des Telecomm Alternate synchronization device for two rotating switches

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FR1269241A (fr) 1961-08-11
FR85504E (fr) 1965-12-03
DE1286617B (de) 1969-01-09

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