Abstract: A torque-responsive brake, in particular for elevators, comprises two or more brakes arcs, brake shoes pivotally connected to the brake arcs and having attached brake linings and a brake actuating mechanism for pressing the brake linings against a drum. With prior art brakes, the starting of the elevator was not smooth enough or, alternatively, the types of apparatus by which smooth starting has been achieved were too complicated and expensive. By the present invention these drawbacks have been overcome in that, for pivotally attaching each brake shoe to its brake arc, a pivot shaft extends through the respective brake shoe and is connected to one end of a torque-responsive member, the opposite end of which is fixed to the respective brake arc.
Abstract: A method of and apparatus for counting objects present within a predetermined area, by detecting acceleration and deceleration of the objects employ at least one Doppler radar to sense the movements of the objects by monitoring the Doppler frequencies of signals reflected from the objects, amplifying the Doppler signal reflected from each of the objects to provide an amplified signal, effecting an automatic gain control of the amplified signal to provide a signal of substantially constant strength independent of the distance and size of the respective object, detecting a frequency variation of the constant strength signal as an indication of change in the speed of movement of a respective one of the objects, determining whether the constant strength signal represents an acceleration or deceleration of the respective object, and correspondingly modifying a count representing the number of the objects in the predetermined area.
Abstract: A method of and apparatus for regulating the control voltage of a three-phase inverter supplying an a.c. motor are provided, the inverter having a power stage implemented with semiconductor switches, and the output voltage of each inverter phase being measured in the voltage control. For rapidly improving the curve shapes of the inverter output by means of feedback, the control voltage of the pulse width modulator of each inverter phase is regulated by a voltage regulator. The control voltage obtained as output of the voltage regulator is derived from an actual value voltage formed from the output voltage of each inverter phase and a reference voltage.
March 16, 1987
Date of Patent:
January 17, 1989
Kone Elevator GmbH
Matti Kahkipuro, Urpo Sten, Pekka Nummi, Pekka Hytti
Abstract: A method of forming the amplitude of the reference voltage of a three-phase inverter supplying a squirrel cage motor requires no current measuring elements. In this method, the amplitude is formed by finding in predetermined constant flux curves which represent the squirrel cage motor in question, and in which the motor rotor current frequency appears as parameter, a curve from which is obtained the amplitude of the motor stator voltage, i.e. of the inverter reference voltage, corresponding to the frequency of the motor's stator voltage, i.e. of the inverter reference voltage, so that the magnetic flux in the stator will be constant.
Abstract: A method for directing the power of a d.c. voltage source between a three-phase mains and a d.c. circuit, which comprises the steps of employing a diode bridge comprising a plurality of first diodes to rectify a three-phase mains voltage to a d.c. voltge when power is flowing from the three-phase mains to the d.c. circuit, converting the d.c. voltage to a three-phase a.c. voltage, when power is flowing from the d.c. circuit to the three-phase mains, by means of transistors in parallel with the diodes, employing control means for controlling the transistors, forming control voltages for the control means by a plurality of second diodes from the three-phase mains in such manner that each the transistor is conductive during the conduction time of the respective diode in parallel therewith, and shortening the conduction times of the transitors, in order to reduce the power circulating in the d.c. circuit, by connecting Zener diodes in series with respective ones of the transistors.
Abstract: An elevator has a drive mechanism connected to a traction sheave provided with grooves, over which run parallel suspension cables, and an elevator cage and an associated counterweight suspended from the suspension cables. The elevator is also provided with at least two diverting pulleys over which the suspension cables run and of which at least one diverting pulley is associated with the traction sheave in such manner that the suspension cables extending from the elevator cage to the counterweight have first and second wraps around the traction sheave and, between these wraps, a further wrap around the diverting pulley. Prior art traction sheave elevators exhibit insufficient friction between the traction sheave and the suspension cable, for which reason it is necessary, in the case of elevators of great heights, to use so-called compensating cables, which add to the weight of the elevator.
Abstract: A capacitive safety system for controlling a door, e.g. an elevator door, so as to automatically avoid obstacles, employs electronic control for antennas operating as capacitive measuring elements for establishing shield voltages of identical phase on the antennas and on shield voltage antennas to counteract ambient capacity variations. In order to improve the operation and safety of the elevator door, the elevator shaft door, which closes simultaneously with the elevator door, is provided with similar capacitive measuring antennas and electronic controls as the elevator door, as well as with similar shield voltage antennas, which operate on a shield voltage having the same phase as that of the elevator door. Operation of the elevator shaft door and the elevator door with identical phases is effected by means of a wireless shield voltage transfer unit.
Abstract: A method of and apparatus for continuously counteracting lateral oscillation of an elevator car provided with guide shoes running along guide rails by laterally displacing the guide shoes in accordance with the out-of-straightness of the guide rails by ascertaining the magnitudes of local deviations of the guide rails from a straight condition thereof and setting up in the memory of a computer controlling the guide shoes a deviation table relating the local deviations to the position of the car along the path of travel, and subsequently controlling the guide shoes by the computer in dependence on the table to displace the elevator car laterally to compensate for the local deviation at any position of the elevator car at which the local deviations occur.
Abstract: A method of and apparatus for controlling a braking resistor, provided in a d.c. circuit of a frequency converter, by rectifying a mains voltage, by means of a first rectifier bridge connected to a three-phase mains supply, to form an actual value voltage; comparing said actual value voltage and a reference voltage; and operating a switch in series with the braking resistor to cause the latter to conduct when the comparison indicates that the actual value voltage is greater than the reference voltage. The reference voltage is formed from a rectified voltage obtained from the three-phase mains supply and rectified by a second rectifier bridge.
May 20, 1987
Date of Patent:
April 12, 1988
Kone Elevator GmbH
Matti Kahkipuro, Harri Hakala, Pekka Nummi, Urpo Sten
Abstract: A procedure for entering into an elevator control computer information specific to a particular installation of an elevator provided with operating devices capable of data transfer includes employing a computer test programme to map elevators used in the particular installation and their positions by sending out a query round to addresses which are tabulated in the computer and which represent all possible operating devices, and by inferring the kind and number of the action means present in the installation on the basis of the answers received in the query round. During a test travel of the elevator, by activating and reading the devices the location of the devices, the geometry of the building and the distances between floors are sensed. All the information thus received and which is necessary for controlling the elevator is stored permanently in the memory of the control computer, to enable normal operation of the elevator in the installation.