US3552524A - Speed dictation apparatus for elevator motor control system - Google Patents

Speed dictation apparatus for elevator motor control system Download PDF

Info

Publication number
US3552524A
US3552524A US795842A US3552524DA US3552524A US 3552524 A US3552524 A US 3552524A US 795842 A US795842 A US 795842A US 3552524D A US3552524D A US 3552524DA US 3552524 A US3552524 A US 3552524A
Authority
US
United States
Prior art keywords
signal
speed
car
voltage
output
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US795842A
Other languages
English (en)
Inventor
Sidney Howard Benjamin
Otto Albert Krauer
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Otis Elevator Co
Original Assignee
Otis Elevator Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Otis Elevator Co filed Critical Otis Elevator Co
Application granted granted Critical
Publication of US3552524A publication Critical patent/US3552524A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66BELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B1/00Control systems of elevators in general
    • B66B1/34Details, e.g. call counting devices, data transmission from car to control system, devices giving information to the control system
    • B66B1/46Adaptations of switches or switchgear
    • B66B1/52Floor selectors

Definitions

  • a a corporamn Jersey ABSTRACT Speed dictation apparatus for a high-speed elevator motor control system which generates a time-controlled speed dlClatlOll signal to 6911 1101 the speed Of the car in a predetermined manner so that it is accelerated at the same MOTOR CONTROL SYSTEM 9Chims, 10 Drawing Figs predetermined ate for any length of trip. A distance-controlled speed dictation signal is also generated. Th1s lS opera- [52] US.
  • a high-speed elevator system is herein meant one in which the minimum distance required to bring the car to a stop from its full rated running speed without discomforting passengers is greater than the floor height between two normally separated adjacent landings. This is not to be interpreted however as meaning that a car in such a system cannot provide service between adjacent landings by starting at one and stopping at the other. On the contrary, the car is nevertheless capable of making such one floor runs because the maximum speed it is permitted to attain on these runs is limited to an amount less than the full rated running speed. Thus, a high-speed elevator system is capable of initiating a comfortable stopping operation at any car speed up to and including its full rated running speed.
  • Another object of the invention is to provide apparatus by which anelevator car is accelerated at the same predetermined rate for any length of trip solely as a function of time in response to the operation of a time-controlled speed dictation signal-generating device and decelerated in a desired manner as a function of distance in accordance with the operation of a distance-controlled speed dictation signal-generating device.
  • One feature of the invention involves arranging an elevator installation so that its time-controlled speed dictation signalgenerating means not only generates a time-controlled signal which determines the acceleration of the car but also generates a time-controlled signal which is operable to determine the deceleration of the car.
  • the car is not decelerated in accordance with this latter control signal, however. Instead, the car is actually decelerated in the desired manner in accordance with a distance-controlled signal generated by a distance-controlled speed dictation signal-generating means which is operable to decelerate the car as a function of its distance from a selected landing at which it is to stop.
  • a motor control system is arranged to control the speed of an elevator car by controlling the speed of the hoisting motor which drives the car.
  • speed-regulating equipment including a speed-determining output voltage generator .in the form of an integrating amplifier to receive speed-determining output voltage therefrom.
  • a time-controlled speed dictation signal-generating means including acceleration and deceleration signal function generators and a capacitive circuit, is connected to the input of the integrating amplifier.
  • the acceleration signal function generator applies an input to thecapacitive circuit so that in response the integrating amplifier on each individual trip generates a time-controlled acceleration dictation voltage which regardless of the length of the trip operates to control the acceleration of the car at the same predetermined rate as a function of the time elapsed from the reception of the signal to start.
  • the time-controlled speed dictation signal-generating means transfers its operating mode by switching the input to the capacitive circuit from its acceleration signal function generator to its deceleration signal function generator.
  • the time-controlled speed dictation signal-generator means thereafter generates signals which are operable to cause the integrating amplifier to control the speed of the car during its deceleration in a predetermined manner as a function of the time elapsed from the transfer to the'deceleration signal function generator.
  • the speed regulating equipment connects the output of the integrating amplifier through a summation amplifier in a feedback arrangement with the output of a distance-controlled speed dictation signal-generating means in the form of a landing selector mechanism.
  • the landing selector mechanism generates an output signal which is operable to control the speed of the car in a predetermined manner during its deceleration as a function of the distance of the car from the selected landing.
  • the difference between the output of the integrating amplifier and the output from the landing selector mechanism is applied to the input of the integrating amplifier to cause it to change its output and conform it to the signal generated by the landing selector mechanism.
  • the magnitude of the feedback signal and the response time of the system determine the speed at which conformity occurs.
  • the system is so designed that at some portion of the deceleration period and for the majority thereof the output signal from the integrating amplifier controls the deceleration of the car in accordance with the manner in which the landing selector mechanism signal would control it.
  • FIG. 1 is a simplified schematic of an elevator control system embodying the invention
  • FIG. 2 is a schematic of a capacitive circuit and various signal function generators in block diagram form including acceleration and deceleration signal function generators for controlling both the upward and downward travel of an elevator car;
  • FIG. 3a is a logic diagram in straight line form of the switching logic functions employed to produce a signal to initiate the deceleration of the elevator car of the system of FIG.
  • FIG. 3 b is a schematic diagram of one implementation of circuits for generating the switching logic functions shown in FIG. 3a;
  • FIG. 4 is a number of logic diagrams in straight line form similar to that of FIG. 3a;
  • FIG. 5 is a'schematic diagram of a. plurality of comparator circuits
  • FIGS. 7 and 8 are graphs on which distance is represented by the abscissa and both velocity and voltage by the ordinate;
  • FIG. 9 is a graph on which time is represented by the abscissa and velocity by the ordinate.
  • an elevator car 10 and its counterweight 11 in typical fashion are supported by hoist ropes 12.
  • the car moves whenever brake 13 is lifted and motor 14 receives power from motor control equipment 15 to rotate sheave 16.
  • motor control equipment 15 In rotating sheave 16, shaft 18 of motor 14 drives tachometer generator 17 to provide a voltage on line V146 proportional to the speed of car 10.
  • Motor control equipment 15 may be any suitable equipment, the equipment disclosed in the copending application of Otto Albert Krauer et al., Ser. No. 495,585 filed Oct. 13, 1965, now U.S. Pat. No. 3,442,352, and assigned to the assignee of the instant application being presently preferred.
  • the landing selector mechanism may be any one of several, such as that disclosed in the copending application of Otto Albert Krauer et al., Ser. No. 495,446, filed Oct. 13, 1965, now U.S. Pat. No. 3,442,352 for ELEVATOR CONTROL SYSTEM, and assigned to the assignee of the instant application; or that disclosed in the copending application of Herbert Frederick Voigt et al., Ser. No. 795,841, filed Feb.
  • gearboxes GBI, G82, and GB3 are gearboxes GBI, G82, and GB3.
  • gearbox GBl are cams AFDC and HXC for operating mechanical switches AFDS and I-IXS which, respectively produce signals AFD and I-IX directly and signals Kfi' d Hi through inverters INV6 and INV7.
  • Gearboxes G32 and GB3 each respectively drives sliding contact, or wiper, BRl of coarse potentiometer POTl and sliding contact, or wiper, BR2 of fine potentiometer POTZ. These potentiometers have their center points grounded and their end terminals connected across voltages V5, V5+ and V6, V6+ respectively.
  • Motor control equipment 15 for hoisting motor 14 is connected through contacts l-IXA2 of stopping switch I-IXA along line LSF to sliding contact BR2 of potentiometer POTZ.
  • the motor control equipment is connected through contacts HXAl to the output circuit of the speed regulating equipment.
  • a speed determining output voltage generator and voltage control equipment included in the speed regulating equipment.
  • the speed dictation output voltage generator includes operational amplifier MIA arranged as an integrating amplifier having input circuits through resistors DARl and CORS is connected through contacts DCVSl and CPL] of decelerating switches DCVS and CPL to the voltage control .equipment.
  • Condenser MIQ connected in parallel with resetting resistor MIDR through contacts I-IXA3 and positive and negative voltage clamping circuits are connected from the input to the output amp ifier MIA;
  • the positive clamping circuit includes diode PCI) and resistors PCRl and PCRZ connected to voltage source Vl-.
  • the negative voltage clamping circuit includes diode NCD and resistors NCRl and NCRZ connected to positive voltage source Vl+.
  • the voltage control equipment of the speed regulating equipment includes inverting amplifier COAl, its input and output resistors CORl and COR3 and its scaling resistor CORZ.
  • Input resistor CORl is connected to the output circuit of integrating amplifier MIA.
  • Output resistor COR3 is connected in one of the input circuits to summation amplifier COA2, whose output circuit is connected through contacts DCVSl and CPU to resistor CORS.
  • Connected in the second input circuit to summation amplifier COA2 through resistor HDCR and along line HSF is sliding contact BR! of potentiometer POTl.
  • a time-controlled speed dictation signal-generating means including up-and-down direction signal function generators which are connected to line DA by way of capacitive circuit DAX comprising condenser DAQ and resetting resistor DAR2. Resetting contacts I-IXA4 connect line DA to ground.
  • FIG. 3a is a logic diagram in straight line form. This diagram may be interpreted to read that the function along line DDC is present, that is, the signal along line DDC changes to a binary 1 value, if the function along line HX is present and the function along either line DCV or line SCC or line FSR is present.
  • the signal along line DDC continues at the binary 1 value as long as the function along line I-IX is present.
  • the signal along line DDC changes to a binary I value
  • the signal along line DDC from inverter INVZ changes to a binary 0 value to signify its absence, and vice versa.
  • FIG. 3a may be implemented in any number of ways.
  • relay circuits may be employed in which contacts of the relays represent the presence or absence of the various functions.
  • NAND circuits are used to perform these switching logic functions.
  • FIG. 3b illustrates the NAND circuits which perform the logic functions of FIG. 3a in AND/OR logic.
  • each OR circuit of FIG. 3b, 0R1, CR2 and CR3 has each of its inputs inverted and, therefore, performs a NAND function.
  • Each of the AND circuits of FIG. 3b, AND] and AND2 has its output inverted and therefore it also performs a NAND function.
  • all the logic functions shown in FIG. 4 may preferably be implemented by NAND circuits in combination with the time delay circuits designated TD and the inverters designated INV. In an attempt to simplify the drawing, however, the NAND circuits for implementing these functions have not been shown.
  • Comparators SCCCOM, and ESMlCOM contain contacts U2, D2, U3 and D3, in their input circuits. These U and D contacts respectively connect negative and positive voltage sources to their respective comparators depending upon whether or not the car is moving up or down.
  • the output of comparator SCCCOM is connected as one input to AND circuit AND3. An additional input is connected along line ADL.
  • FIGS.'7 and 8 A scale is shown on FIGS.'7 and 8 both for the distance abscissa and for the ordinate representing velocity to aid in understanding the specific operation which is hereinafter described. No voltage scale is shown for the voltage ordinates since such a scale is peculiarly a matter of choice and design in relation to the specific equipment used for particular elements of the control system.
  • relay driver RDHX (FIG. 6) to remove energizing voltage from the coil of relay I-IXA causing it to release to open contacts I-IXAZ, I-IXA3, and I-IXA4 and to close contact HXAl.
  • capacitive circuit DAX applies a signal along line DA through resistors DAR] and DAR2 to the input of integrating amplifier MIA (FIG. 1) of the speed-determining output voltage generator.
  • MIA integrating amplifier
  • integrator MIA produces a desired velocity signal on line DV through contacts HXAl which when applied to motor control equipment causes the elevator car to start with a rate of change of acceleration of 8 feet per second until it reaches a constant acceleration of 4 feet per second This constant acceleration continues until either the generation of a signal to stop causes it to change or until the dictated car speed reaches a velocity equal to 1 foot per second less than its desired maximum velocity, or as it is better known, its full rated running speed.
  • Comparator FSMlCOM (FIG. 5) responds to this condition by comparing a fixed value of voltage along line V2- equivalent to 1 foot per second less than full-rated running speed with the output from integrating amplifier MIA along line DV. When these two compared signals are equal, comparator FSMlCOM produces a binary 1 signal along line FSMl.
  • the advance floor scanner of the selector at this time has advanced a distance equivalent to more than the full-speed stopping distance.
  • shaft 694 through gearbox 631 has driven cam AFDC into engagement with switch -AFDS to close it contacts and produce a binary signal along line AFD.
  • the binary 1 signal along line FSR is applied through time delay circuit TDl to produce a binary 1 signal along line TFSR. This makes the binary 1 signal along line FSR self-holding as long as the signals along lines AFD and DCV maintain the binary I state.
  • the time delay is required when the logic function circuit is implemented with NAND circuits to stabilize the self-holding circuit and prevent misoperation.
  • the binary 1 signal along line FSR is also applied tm erter INVl to cause the signal along line FSR. to change to the binary 0 condition.
  • the circuit for the production of a binary 1 signal along line DAC is inter rupted changing the signal along that line to the binary 0 condition. Consequently, the signal along line DAU also changes to the binary 0 condition.
  • the binary 1 signal along line FSR is also employed in conjunction with the binary 1 signal along line U to cause the production of a binary I signal along line FSU (FIG. 4).
  • the binary l signals along line FSR and l-IX cause the production of a binary 1 signal along line DDC (FIGS. 3a and 3b).
  • This signal is applied to inverter INV2 to produce a binary 0 signal along line DDC.
  • the binary 1 signal along line DDC is also applied through time delay TD2 to produce a binary 1 signal along line TDDC. This causes the binary signal along line DDC to be self-holding as long asthe signal along line HX remains in the binary I state.
  • the binary l signals along line DDC and line U cause the production of a binary 1 signal along line DDU (F IG. 4).
  • the binary 0 condition of the signal along line DAU switches off up-direction acceleration signal function generator UAFG (FIG. 2) while the binary 1 condition of the signals alonglines FSU and DDU switches on up-direction full-speed signal function generator UFFG (FIG. 2) and up-direction deceleration signal function generator UDFG (FIG. 2).
  • this causes the voltage across condenser DAQ to increase from the potential of V to that of V,,.
  • the selector advance floor scanner selects a landing at which a stop is required and a signal to stop is generated. This causes the scanner to stop its scanning operation at a position corresponding to that landing.
  • the continued movement of the car in approaching the selected landing causes shaft 694- to rotate the gears of gearboxes GBl, GB2 and G83 in a direction opposite to that in which they had previously been turning.
  • cam AFDC (FIG. 1) opens the contacts of switch AFDS.
  • this signal is compared with the inverted output of integrating amplifier MIA which is produced by inverting amplifier COAl (FIG. 1). This comparison is such as to produce an algebraic summation which is generated as an output voltage from summation amplifier COAZ.
  • This voltage is applied to the input circuit of integrating amplifier MIA through resistors CORS to cause the output voltage of amplifier MIA to conform to the output voltage along line I'ISF.
  • the rate at which conformity takes place is determined by the size of the difference signal which is applied through resistor CORS. In the herein described tested embodiment conformity takes place most satisfactorily while the car is decelerating at 4 feet per second so that thereafter the voltage along line DV which is applied to motor control equipment 15 is identical to that of curve B of FIG. 7.
  • gearbox GBl causes its attached cam HXC (FIG. 1) to open the con% of switch HXS to produce a binary 1 signal along line HX.
  • relay driver RDHX to energize relay l-IXAl (FIG. 6) causing contacts HXAZ (FIG. 1) to engage and contacts I-IXAl (FIG. 1) to disengage.
  • the car is approximately 2 feet from the location of the selected landing.
  • the output voltage along line LSF from sliding contact BR2 (FIG. 1) of potentiometer POTZ is equal to the output voltage along line HSF from sliding contact BR1 of potentiometer POTl.
  • motor control equipment 15 When contacts HXAI open and contacts l-IXA2 close, motor control equipment 15 no longer operates in response to the output voltage from integrating amplifier MIA but rather operates directly in response to the output voltage from sliding contact BRZ of potentiometer POTZ.
  • This voltage brings the car rapidly and accurately into the landing level. Ideally this would decelerate the car from a distance 2 feet from the selected landing at a constant deceleration of 4 feet per second until a velocity of 1 foot per second was attained. Thereafter the car would decelerate at a rate of change of 8 feet per second until it reached zero velocity.
  • the final approach to the floor is slightly different from the ideal and this is done so as not to introduce instability into the system.
  • the final approach to the floor is not controlled by a time-controlled output voltage which is forced into conformity with a prescribed distance-controlled voltage but rather is controlled by a distance control voltage directly.
  • a function generator could be provided to produce a time-controlled signal which would be operable to bring the car to a stop in the ideal manner as a function of time.
  • This could be applied to integrating amplifier MIA and its output voltage could be forced into conformity with the output voltage along line LSF from sliding contact BR2 of potentiometer POT2. If the car were to be decelerated in this manner the transfer from control by a time-controlled signal which is forced into conformity with a distance-controlled signal to control by a distance-controlled signal directly would be eliminated.
  • a trip at full rated running speed has just been described.
  • An example of a trip at less than full speed will aid in completely understanding this invention.
  • a signal to start has been received and that the car is again accelerating in the up direction at a rate of 4 feet per second in the manner previously described.
  • the selector mechanism advance floor scanner selects a landing at which a stop is required and a signal to stop is generated which causes the scanner to stop its scanning operation at a position corresponding to the landing, and that this landing is not far enough away from the landing from which the car started to permit it to reach full rated running speed.
  • the stopping operation of the car is initiated by a signal to stop accelerating which is received while the car is accelerating at a constant acceleration of 4 feet per second
  • Passenger comfort can be assured by initiating the stopping operation when the velocity of the car and its distance from the selected landing are such that the acceleration of the car can be decreased at a rate of change of 8 feet per second for one-half second until the acceleration ceases, whereupon the car can be slowed down at a rate of change of deceleration of 8 feet per second.
  • the car can be brought to a stop in accordance with the hereinbefore described operation.
  • curve B of FIG. 7 represents the manner in which the potential of the output voltage along line HSF from sliding contact BR1 of potentiometer POTl decreases after a landing is selected.
  • this voltage is operable to decelerate the car at a constant rate as a function of its distance from a selected landing until the car is within approximately 2 feet of that landing. From this, it should be understood that whenever a car is more than 2 feet from a selected landing, this output voltage represents he desired velocity of the car as a function of its distance from the selected landing while it is decelerating to a stop at that landing in the manner desired. At distances greater than 2 feet, curve B, represents this velocity with respect to the ordinate velocity scale of FIG. 7.
  • V the desired constant deceleration velocity represented by the output voltage from contact BRl after the selection of a landing
  • V the maximum constant acceleration velocity represented by the output voltage from tachometer generator 17
  • the signal to stop accelerating is to be generated whenever the actual velocity of the car and the velocity represented by the output voltage from sliding contact BRl bear the relationship to each other defined by the above equation.
  • car speeds of interest i.e. from 3.75 feet per second to about 27 feet per second, it has been found satisfactory to generate the signal to stop accelerating when these velocities bear a less complex relationship to each other. This relationship is defined by the equation:
  • Comparator SCCCOM (FIG. computes the existence of this latter equality and generates a signal to stop accelerating as a result thereof.
  • the description of the trip at less than full rated running speed will continue. It will be recalled that the car is traveling in the up direction. Thus, contacts U2 are closed. This applies a negative potential VII-equivalent to 3.2 feet per second along line U4 to comparator SCCCOM.
  • the selector advance floor scanner has stopped its scanning and has selected a landing at which it is desired to stop. This, as is later explained, operated to close contacts ADLSI (FIG. 5) and to apply a binary 1 signal along line ADL to AND circuit AND3.
  • the production of the binary 1 signal along line SCC becomes self-holding through the binary 1 signal along line HX and in conjunction therewith completes a circuit for the logic function signal along line DDC (FIG. 4) causing that signal to change to the binary 1 condition.
  • the binary 1 signal along line DDC completes the circuit for the logic function signal along line DDU (FIG. 4) and changes that signal to a binary I. This energizes up direction decelerating signal function generator UDFG (FIG. 2) which applies its output signal across capacitive circuit DAX (FIG. 2).
  • selector mechanism 22 generates four separate signals.
  • One of these signals commences when the advance floor scanner selects a landing and stops its scanning operation.
  • the source of this signal has previously been designated by contacts ADLSl (FIG. 5).
  • a second signal exists whenever the advance floor scanner signifies its location in a position corresponding to a position 2 feet or more in advance of the position of the car in the hoistway.
  • Contacts HXS (FIG. I) have previously been designated as the source of this signal.
  • a third signal exists whenever the car is full-speed stopping distance or more from a floor at which it is to stop.
  • the source of this signal has previously been designated by contacts AFDS (FIG. 1).
  • the fourth signal is a continuous indication of the distance the advance floor scanner signifies it is from the indicated position of the car.
  • the first abovementioned signal may be generated by breaking contacts (i.e. contacts which disengage and engage when the coil of the switch which operates them is energized and deenergized,
  • the firstauxiliary stopping relay A the second signal, by switch 102 if it is set to close its contacts and keep them closed whenever the advance floor scanner is at a location corresponding to a position in the hoistway 2 or more feet in advance of that of the car; the third signal, by switch 121 if it is set to close its contacts and keep them closed whenever the car is full speed stopping distance or more from a landing at which it is to stop; and the fourth signal, by the angular position of shaft 694.
  • selector 22 transduces the angular position of shaft 694 into a signal suitable to perform the functions previously attributed to it.
  • this signal corresponds to curve B of FIGS. 7 and 8.
  • shaft 694 drives sliding contacts BR] and BR2 of potentiometers POTl and POTZ through suitable gearing.
  • the voltages at sliding contacts BR! and BR2 are each a function of the distance between the advance floor scanner and the indicated position of the car. From previous explanations it will be appreciated that after landing selection, it is desired that these voltages, although functions of distance, each have a form which will dictate the described operation as if each were a function of time. The following describes how this is achieved.
  • the curve of FIG. 9 represents the velocity characteristics for a typical run of an elevator car operated in the hereinbefore mentioned ideal manner.
  • the jerk, j is constant and equal to 8 feet per second. Assuming that the car starts from a first landing at t and that distances is measured from this landing, the following relationships can be derived by straightforward mathematics:
  • the potentiometer is a multiturn rotary one whose wiper makes no more than one transit from the center tap of its resistance element to either of its extremities while the advance floor scanner travels a distance equivalent to full-speed stopping distance ahead of the car in either direction.
  • the output voltage from sliding contact BRl indicates, by its polarity, whether the car is above or below a selected landing, and represents, by its magnitude, the velocity at which the car should be traveling during its constant deceleration period at any distance from a selected landing, if it is to stop in the described manner,
  • the magnitude of voltages V5+, VS- are sufficient to extend the magnitude of the output voltage from contact BRl to and beyond that indicative of the full speed stopping distance.
  • potentiometer POTl is suitable to provide the described operation only at distances greater than one-sixteenth foot from the landing and, furthermore, as has been explained, that operation is desirable only at distances greater than about 2 feet.
  • curve B of FIG. 8 The portion of curve B of FIG. 8 below one-sixteenth foot has a slope which becomes infinite as the distance from the floor approaches zero. If a signal were to be generated in accordance with this curve, it would dictate a very large change in velocity for a very small change in distance. Motor control systems which could follow such a signal in the region near zero would be required to have substantially infinite gain. This, of course, is not feasible. Additionally, as the gain of these systems is increased, problems of stability increase. These considerations impose a practical upper limit on the slope of the velocity versus distance curve in the region closer than one-sixteenth foot from a selected landing.
  • curve B is replaced, in the region near zero distance, with curve C of FIG. 8.
  • This curve is derived by first determining reasonable minimum and maximum slopes based on the foregoing considerations of gain, stability and accuracy. Next the first portion of curve C is drawn, keeping its slope less than the maximum, and greater than the minimum, in the region below one-sixteenth foot, to provide a signal adequate for accuracy purposes in this region. The remainder of curve C is extended from the first portion, either continuously or in steps, so as to join smoothly with curve B being careful not to exceed the maximum slope. It has been found feasible to make a smooth transition at a distance of approximately 2 feet by making the ordinates of curve C substantially equal to those of curve B in the region from 1% to 2% feet.
  • Potentiometer POT2 (FIG. 1) is constructed to have a nonlinear resistance versus rotation characteristic on each side of its center tap in accordance with curve C of FIG. 8, regarding the abscissa as degree of rotation and the ordinate as resistance.
  • a one turn rotary potentiometer whose wiper can turn continuously through zero in either direction and which makes one full revolution for each 6 feet of car travel has been found to be satisfactory for potentiometer POT2. It also may be constructed by connecting suitable shunts across a plurality of taps. As in the case of potentiometer POTl, voltages of opposite polarities V6+, V6- are connected to opposite extremities and the center tap is grounded.
  • Potentiometer POTZ may be connected in place of potentiometer POT] when the elevator car is anywhere in the region between 1% and 2% feet from the landing.
  • switching is effected by switch HXS which is operated in this region by shaft 694 through gearbox GBl.
  • curve C instead of curve B is that the time required to bring the car to the landing is increased.
  • the increase is small because the variation from the ideal operation to the described desired one is slight and occurs only in the region below 2 feet.
  • the accuracy with which the distance controlled voltages can position the car at any landing level depends upon the accuracy with which the advance floor scanner or advancer carriage mechanism 703 is located at a position corresponding to that landing.
  • a high degree of Stopping accuracy i.e. stopping the car within at least /4 inch of any landing, is obtainable first, by establishing the contacting surfaces between each lug 706 and pawls 704 and 705 so that each pawl stops the advancer carriage mechanism with the same accuracy at each position corresponding to a landing and second, by utilizing two separate coarse potentiometers and two separate fine potentiometers, one each for each direction of travel instead of one coarse and one fine eachfor both directions of travel as previously described.
  • apparatus for controlling the speed of travel of a highspeed elevator car in which the car starts on any trip by accelerating in response to asignal to start and completes each trip by decelerating to a stop at a selected one of a plurality of landings in response to a signal to stop thereat, apparatus comprising:
  • time-controlled speed dictation signal-generating means operating in response to the reception of each signal to start and on each individual trip generating a time-controlled speed dictation signal which is operable to control the speed of the car in a predetermined manner so that said car is accelerated at the same predetermined rate regardless of the length of the trip; landing selector mechanism operating during each individual trip of said car in response to the reception of the signal to start on that trip and the signal to stop the trip at a selected landing and generating a distance-controlled speed dictation signal operable to control the speed of said car in a predetermined manner during its deceleration as a function of the distance of said car from said selected landing; speed regulating equipment connected to said time-controlled speed dictation signal-generating means and to said landing selector mechanism and during each trip generating an output signal in response to said time-controlled and said distance-controlled speed dictation signals;
  • said time-controlled speed dictation signal-generating means includes an acceleration signal function generator operating in response to the reception of each signal to start and on each individual trip generating a time-controlled acceleration dictation signal which regardless of the length of said trip is operable to accelerate said car at the same predetermined rate as a function of time and a deceleration signal function generator operating in response to the reception of a signal to stop at a selected landing during each individual trip of the car and generating a time-controlled speed dictation signal operable to control the speed of said car during its deceleration in a predetermined manner as a function of time.
  • said speedregulating equipment includes both an output voltage generator and output voltage control equipment
  • said output voltage control equipment being connected to said landing selector mechanism to receive its distancecontrolled speed dictation signal and in response to the reception of a signal to stop at a selected landing generating a voltage proportional to the difference between said distance-controlled speed dictation signal and the output signal of said speedregulating equipment;
  • said output voltage generator during the deceleration of i said car receiving the time-controlled dictation signal from said deceleration signal function generator and the proportional difference voltage from said output voltage control equipment and generating in accordance therewith as the output signal of said speed-regulating equipment an output voltage whereby the difference between the output signal of said speed-regulating equipment and said distance-controlled speed dictation signal is continuously reduced until the former conforms to the latter.
  • acceleration signal function generator is connected to said output voltage generator in response to the reception of a signal to start and disconnected therefrom in response to the reception of a signal to stop whereupon said deceleration signal function generator is connected to said output voltage generator.
  • time-controlled signal-generating means includes a capacitive circuit and during each trip of said car said acceleration and deceleration signal function generators generate voltages of opposite polarities which produce predetermined voltage charges across said capacitive circuit.
  • said output voltage generator includes an integrating amplifier having an input circuit and an output circuit, said input circuit being connected to said capacitive circuit to receive being connected to said motor control equipment, said integrating amplifier integrating the voltage received by said input circuit and producing an output speed-determining voltage at its output circuit from which it is received by said motor control equipment, said output voltage generator including voltage output clamping circuits for clamping the output speed-determining voltage of said integrating amplifier at predetermined minimum and maximum magnitudes.
  • said output voltage control equipment includes an inverting amplifier, a summation amplifier and decelerating switching means, said inverting amplifier receiving and inverting the output speeddetermining voltage of said integrating amplifier, said summation amplifier algebraically summing the magnitudes of said landing selector mechanism voltage and the voltage produced by said inverting amplifier, and said decelerating switching means connecting said summation amplifier to the input circuit of said integrating amplifier during each trip of said car in response to the reception of a signal to stop at a selected landing whereby the input voltage thereafter applied to said integrating amplifier comprises the algebraic sum of the voltage across said capacitive circuit resulting from the voltage generated by said deceleration signal function generator and the difference between said landing selector mechanism voltage and the output speed determining voltage produced by said integrating amplifier.
  • said output voltage control equipment includes stopping switching means responsive during each trip of said car to the approach of the car within a predetermined distance of the selected landing at which a stop is to be made disconnecting said motor control equipment from the output circuit of said integrating amplifier and connecting it to receive the voltage generated by said landing selector mechanism.

Landscapes

  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Elevator Control (AREA)
  • Control Of Electric Motors In General (AREA)
  • Control Of Position, Course, Altitude, Or Attitude Of Moving Bodies (AREA)
  • Control Of Ac Motors In General (AREA)
US795842A 1969-02-03 1969-02-03 Speed dictation apparatus for elevator motor control system Expired - Lifetime US3552524A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US79584269A 1969-02-03 1969-02-03

Publications (1)

Publication Number Publication Date
US3552524A true US3552524A (en) 1971-01-05

Family

ID=25166587

Family Applications (1)

Application Number Title Priority Date Filing Date
US795842A Expired - Lifetime US3552524A (en) 1969-02-03 1969-02-03 Speed dictation apparatus for elevator motor control system

Country Status (15)

Country Link
US (1) US3552524A (de)
JP (1) JPS5122275B1 (de)
BE (1) BE745428A (de)
BR (1) BR7016523D0 (de)
CA (1) CA1002673B (de)
CH (1) CH515845A (de)
DE (1) DE2004812C2 (de)
DK (1) DK137985B (de)
ES (1) ES376145A1 (de)
FI (1) FI54584C (de)
FR (1) FR2033889A5 (de)
GB (1) GB1263875A (de)
NL (1) NL168787C (de)
NO (1) NO131542C (de)
SE (1) SE374529B (de)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3759350A (en) * 1972-05-30 1973-09-18 Westinghouse Electric Corp Elevator system
US4016496A (en) * 1974-12-16 1977-04-05 Canadian General Electric Company Limited Method and apparatus for producing ramp signals with rounded inflection points
US4084662A (en) * 1975-09-01 1978-04-18 Nippon Otis Elevator Company Control apparatus for an elevator system
US4130184A (en) * 1976-05-27 1978-12-19 Mitsubishi Denki Kabushiki Kaisha Elevator speed control system
US4136758A (en) * 1976-12-01 1979-01-30 Mitsubishi Denki Kabushiki Kaisha Speed control system of elevator
WO1981001830A1 (en) * 1979-12-27 1981-07-09 Otis Elevator Co Position controlled elevator door motion
US5229558A (en) * 1989-10-31 1993-07-20 Kone Elevator Gmbh Control of an elevator hoisting motor during under voltage conditions in the main power source

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5352585U (de) * 1976-10-06 1978-05-06
US4373612A (en) * 1980-11-25 1983-02-15 Westinghouse Electric Corp. Elevator system

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3350612A (en) * 1964-02-19 1967-10-31 Imp Electric Company Jerkless pattern signal for motor acceleration
US3435916A (en) * 1964-06-04 1969-04-01 Reliance Electric & Eng Co Elevator motor speed control including a high gain forward loop and lag-lead compensation

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1234366B (de) * 1962-02-26 1967-02-16 Impuls G M B H Deutsche Antrieb mit polumschaltbarem Drehstrom-Asynchronmotor fuer aufzuege

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3350612A (en) * 1964-02-19 1967-10-31 Imp Electric Company Jerkless pattern signal for motor acceleration
US3435916A (en) * 1964-06-04 1969-04-01 Reliance Electric & Eng Co Elevator motor speed control including a high gain forward loop and lag-lead compensation

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3759350A (en) * 1972-05-30 1973-09-18 Westinghouse Electric Corp Elevator system
US4016496A (en) * 1974-12-16 1977-04-05 Canadian General Electric Company Limited Method and apparatus for producing ramp signals with rounded inflection points
US4084662A (en) * 1975-09-01 1978-04-18 Nippon Otis Elevator Company Control apparatus for an elevator system
US4130184A (en) * 1976-05-27 1978-12-19 Mitsubishi Denki Kabushiki Kaisha Elevator speed control system
US4136758A (en) * 1976-12-01 1979-01-30 Mitsubishi Denki Kabushiki Kaisha Speed control system of elevator
WO1981001830A1 (en) * 1979-12-27 1981-07-09 Otis Elevator Co Position controlled elevator door motion
US4299308A (en) * 1979-12-27 1981-11-10 Otis Elevator Company Position controlled elevator door motion
US5229558A (en) * 1989-10-31 1993-07-20 Kone Elevator Gmbh Control of an elevator hoisting motor during under voltage conditions in the main power source

Also Published As

Publication number Publication date
NO131542B (de) 1975-03-10
NL168787C (nl) 1982-05-17
CH515845A (de) 1971-11-30
SE374529B (de) 1975-03-10
CA1002673B (en) 1976-12-28
ES376145A1 (es) 1972-03-01
DE2004812C2 (de) 1983-08-04
JPS5122275B1 (de) 1976-07-08
NL7001488A (de) 1970-08-05
NL168787B (nl) 1981-12-16
FI54584C (fi) 1979-01-10
DK137985B (da) 1978-06-19
DE2004812A1 (de) 1970-08-06
DK137985C (de) 1978-11-13
FI54584B (fi) 1978-09-29
BE745428A (fr) 1970-07-16
FR2033889A5 (de) 1970-12-04
GB1263875A (en) 1972-02-16
NO131542C (de) 1975-06-18
BR7016523D0 (pt) 1973-01-02

Similar Documents

Publication Publication Date Title
US3918552A (en) Elevator control system
US3774729A (en) Speed pattern generator for elevator systems
US3523232A (en) Jerk,acceleration,and velocity limited position pattern generator for an elevator system
US3552524A (en) Speed dictation apparatus for elevator motor control system
US3783974A (en) Predictive drive control
GB1436741A (en) Elevator system
US3687235A (en) Control apparatus for an elevator car
US3587785A (en) Elevator control system safety arrangement
US4318456A (en) Terminal slowdown control for elevator system
CN100467365C (zh) 升降机控制方法和用于控制升降机的设备
US3442352A (en) Elevator control system
CN102807142A (zh) 电梯控制装置
GB1485660A (en) Elevator system
US3972389A (en) Elevator stop control arrangement
GB1573544A (en) Method and apparatus for producing a speed pattern for a vehicle
US3599754A (en) Motor control system
USRE28282E (en) Speed dictation apparatus for elevator motor control system
CA1165478A (en) Elevator system
US2847091A (en) Leveling elevator systems
US4213517A (en) Elevator control system
US3507360A (en) Motor arrangement having acceleration control
US3948357A (en) Transportation system with decelerating control
US3516518A (en) Elevator control system
US3599755A (en) Electronic elevator speed control
US4331220A (en) Elevator system