Abstract: A dual band voltage controlled oscillator that has low phase noise. The oscillator includes two voltage controlled oscillators that are each coupled to a tank circuit for adjusting the output frequency. One voltage controlled oscillator operates at a low frequency and one operates at a high frequency. Both voltage controlled oscillators are coupled to a combiner circuit that provides the oscillator output signal. A low frequency bandstop filter is coupled to the output of the second voltage controlled oscillator. The low frequency bandstop filter operates so as to reject the low frequency.

Abstract: The invention uses a resonance Raman spectrometer 1 for achieving the identification and quantitation of analytes including biomolecules, organic and inorganic molecules. According to the present invention, a) a sample 2 is deuterated 3 with D20 for facilitating identification and quantitation of analytes 4 of said sample, b) a monochromatic light 6 illuminates sample 2 of analytes 4 for producing Raman sample light 12 and rejecting Rayleigh light 14, c) the Raman sample light 12 is passed through a depolarizer 19 for producing randomized polarization components 20, d) a Raman sample spectrum 22 is generated, calibrated with respect to an absolute differential Raman cross-section standard in response to said randomized polarization components 22, e) the Raman sample spectrum 22 is provided to a spectral analyzer 24 for identification 26 and/or quantitation 28 of the analytes 4.

Abstract: In an elevator hitch load weighing assembly, a load cell provides an analog load signal to a summer 12, where an analog tare compensation signal is subtracted from the load signal prior to a compensated load signal being provided to an analog-to-digital converter (ADC) 20; the digital load signal is provided to a remaining tare subtractor 26 where tare remaining in the digital load signal is subtracted and a payload provided.

Abstract: A single load cell 10 both (A) measures the load on a elevator hitch providing an analog elevator load signal on line 11 to an analog-to-digital converter 20 via line 18, for providing a digital elevator load signal and (B) is used for providing a dynamic tare of elevator load weighing system for calibrating the analog-to-digital converter 20 by adjusting an analog reference voltage (V.sub.ref) until the digital elevator load signal is equal to the dynamic tare.

Abstract: During motor jerk-out, the real component of a stator current ReI is measured as an approximation to torque current I.sub.T, and a reference acceleration A.sub.ref is obtained as an approximation to the motor acceleration, for providing, by means of linear regression, the Y intercept of a line defining the relationship between ReI and A.sub.ref, which intercept defines ReI at a constant high speed (ReI.sub.CONSTANT HIGH SPEED) for linearly relating ReI.sub.CONSTANT HIGH SPEED to a compensation frequency f.sub.comp, which is provided to a summer for summing f.sub.comp with a reference frequency f.sub.ref used for dictating motor speed. The stator current I and A.sub.ref are sampled during jerk-out when the motor is at high speed because there the real component of the stator current ReI is approximately equal to I.sub.T.

Abstract: The invention is directed to a safety circuit which detects when the car is at least a predetermined distance away from a floor landing while a car door is open. The safety circuit, upon detection of this condition, activates a solenoid located on a safety governor of the elevator car and/or the counterweight, causing safeties to engage, precluding further motion of the car and/or counterweight. The safety circuit comprises the solenoid and a relay having a contact and a coil. Given means for energizing the coil when the elevator car drifts beyond a predetermined distance with a door open, the contact will close, providing power to the solenoid for actuation. The safety circuit preferably employs a relay which indicates whether the car door is open or closed, as well as relays which indicate whether various other system operational checks are satisfactory.

Abstract: An induction proximity sensor 26 is wider than a normal gap between moving escalator steps 10, 12 so that the inductive proximity sensor 26 is always in front of one step or another and provides a constant signal, when steps 10, 12 are passing the inductive proximity sensor 26, and stops the steps 18, 12, 14, 16 when the inductive proximity sensor 26 detects no steps.

Abstract: A microphone 13 is provided upon the ceiling 4 of an elevator hoistway 3 and a loudspeaker 8 upon the top of an elevator car 1. A 9-16 kHz up-sweep is provided to the loudspeaker 8 and a sound signal is transmitted from the loudspeaker 8 to the microphone 13. The travel time of the sound signal is obtained by cross-correlating 53 the sound signal received by the microphone 13 with a reference signal. The reference signal is a received signal in a relatively noiseless environment. By multiplying the travel time of the signal by its velocity, the distance between microphone and loudspeaker is calculated 59. The hoistway temperature is measured 26 and used 57 in the absolute position calculation 59.

Abstract: A permanent magnet 54 mounted on rods 41 passes vertically over a conductive plate 56 in an elevator hoistway 36, a reactive force causes movement of the permanent magnet 54 vertically away from the conductive plate 56 so that a wedge 24 secured to the rods 41 moves within a tapered wedge guide 44 until it contacts an elevator guide rail 14 on which an elevator car 2 is riding, thereby braking the elevator car 2.

Abstract: Elevator swing cars 37 have doors 50 opening into a low rise lobby service corridor 31 and doors 51 opening into a medium rise lobby service corridor 32 with car panels 52 associated with the low rise group of floors (such as floors 1-13) and car panels 53 associated with floors of the medium rise group of floors (such as floors 14-22). Each swing car is assigned (FIG. 12) to either one of the two groups which it can serve at the conclusion of each run, as the car approaches the lobby, thereby operating an enunciator lantern 56 in the low rise corridor 31 or an enunciator lantern 57 in the medium rise corridor 32, depending upon which rise the elevator has been assigned to for service in the next following run. Similar swing cars 39 relate to the medium rise (32) and the high rise (33). A variety of alternatives and features are disclosed.

Abstract: A polyphase motor is powered by an inverter. Each phase winding in the motor comprises two electrically insulated, electromagnetically coupled, conductors, making up a "phase bundle." Each conductor in the bundle is powered by its own transistor drive. The drives for each phase winding respond to a common phase signal for instance from a pulse width modulator.

Abstract: Elevator door dwell time is varied as a function of arrival time so that a show-and-go time is met. The show-and-go time is the time from when the passengers are shown which elevator to board to the time when the elevator door is ready to close after the pasengers have entered the elevator. The arrival time is a function of the distance of the elevator from the floor of the hall call signal and is the time remaining after an elevator reaches a stop control point where a hall call assignment is fixed to a car until the door of said elevator begins to open. Door opening time, door dwell time, and arrival time are subtracted from a show-and-go time. If the difference is greater than or equal to zero, the door dwell time is increased by the difference, but if the difference is less than zero the door dwell time is decreased by the difference, and the doors are then held open at a landing for the door dwell time.

Abstract: An elevator system (FIG. 1) employing a microprocessor-based group controller (FIG. 2) communicating with elevator cars (3,4, . . . ) to derive relative prediction values to be used in a scheme of ultimately assigning, e.g., cars to hall calls at a plurality of floors in the building, using appropriate dispatching strategies based on predicted traffic conditions. In the algorithm of the invention (FIG. 3) the building's inhabitants' behavior based on weekly events, daily events and real time events is predicted, with the events being used to derive relative prediction values based on the weighted summation of the real, daily and weekly values of the events. Weekly events are considered to be those that happened over a past number of weeks (e.g. 10 weeks) on the same day of the week; while daily events are those that happened over the past few days (e.g. 5 days).

Abstract: Drivers for field-controlled switches are powered and switched on and off by the same combined command and power signal which consists of a command signal modulated by a clock signal forming a command envelope including a train of clock pulses. The invention prevents power from being lost by refreshing power during the PWM low state, such that the command high state pulses need not be used for restoring power. Power and a command to a field-controlled driver is provided by a combined command power signal consisting in the on-state of clock pulses, the groups being a function of switch signal pulse width, and in the off-state of absence of clock pulses. During the off-state of the driver, power is refreshed. In addition, by integration the clock pulses a dead time occurs within the driver circuit, while the driver is being switched on with different time constants.

Abstract: The present invention is directed to an elevator dispatching system for controlling the assignment of elevator cars. More particularly, the present invention is directed to a method of determining the commencement and/or conclusion of UP-PEAK and DOWN-PEAK periods of operation. For example, for commencing UP-PEAK operation, a lobby boarding rate is predicted, based on historical information of the number of passengers boarding the elevators at the lobby and the number elevators leaving the lobby. The predicted lobby boarding rate is compared with a predetermined threshold value. If the predicted lobby boarding rate is greater than the predetermined threshold value, UP-PEAK is commenced. In the preferred embodiment, the predetermined threshold value is a predetermined percentage of the elevator car's capacity. Additionally, the present invention is directed to a method of adjusting the threshold value based on actual passenger traffic.

Abstract: Two ultrasonic transducers are provided, one upon the ceiling of an elevator hoistway and the other one the top of an elevator car for measuring the time for an ultrasonic signal to travel from one transducer to another and return for treasuring elevator position.

Abstract: The invention is used in a voltage conversion bridge for use in converting an AC voltage to a DC voltage or inverting a DC voltage into an AC voltage. In a three-phase bridge having one of three reference phase voltages U.sub.A or U.sub.B or U.sub.C associated with each leg, one of the switches S1, S2 or S3 (or alternatively their complements S1*, S2* or S3*) conducts in the time intervals where the associated voltage U.sub.A, U.sub.B or U.sub.C has a higher (or alternatively, smaller) amplitude than the other two reference voltages, and during these times the blanking interval compensation loss is compensated.

Abstract: The present invention is directed to the grouping of contiguous floors in a building into sectors. According to the present invention, historical information regarding the number of passengers arriving at each floor is obtained and used to predict the number of passengers to be arriving at each of the floors. By summing the predicted traffic per floor and dividing by the number of sectors to be formed, average traffic per sector can be determined. In the preferred embodiment, sectors are formed, starting from the first floor above the lobby and continuing through to the top floor in the building, by selecting a set of contiguous floors for each sector such that the predicted traffic for each sector is less than a predetermined threshold. Specifically, if the predicted traffic for a selectable next contiguous floor, added to the predicted traffic for all contiguous floors already selected for the sector, is less than the predetermined threshold, the selectable floor is included in the sector.

Abstract: The invention weighs an elevator car independently of variations in load distribution within the car and variations in the tension distribution in rods and ropes from which the car is suspended. This is accomplished by means of a top hitch plate, a middle hitch plate, and a bottom hitch plate, which are arranged such that the bottom hitch plate has a pivot 16 mounted on it with the middle hitch plate being mounted on the pivot 16 and a load cell and a support being mounted on the middle hitch plate 17 outboard of the rods from which the car 2 is supported. The top hitch plate is connected to a crosshead at its upper surface. The load cell and support bear against the top hitch plate when there is tension in the rods from the weight of the car 2.

Abstract: During up-peak, a dispatcher selecting method chooses among three dispatching algorithms: (i) an up-peak sectoring scheme triggered when two cars leave the lobby fully loaded, (ii) static sectoring, and (iii) dynamic sectoring, in response to any of three criteria: car load, floor population, and average waiting time, allowing a group of elevators to be operated under any three of the dispatching algorithms, not locked into any two.