Abstract: A switch assembly (1) for switching electric circuits comprises a contributory switch (3), a main switch (2), and a flexible element (4). The contributory switch (3) and the main switch (2) are connected electrically in series, the contributory switch (3) and the main switch (4) each comprise at least one movable contact and the flexible element is connected to one movable contact of the contributory switch, a first contact (5a), and one movable contact of the main switch, a second contact (6a).

Abstract: The invention relates to a method and an arrangement for determining an end-of-life of an overvoltage protection element (2) by determining (101) a predefined voltage limit based on a nominal voltage, determining (102) a measuring voltage across switch components (5) of the switch arrangement in connection with a switch-off event, and determining (103) that the overvoltage protection element (2) has reached its end-of-life when the measuring voltage is equal to or lower than the predefined voltage limit.

Abstract: A switch assembly (1) for switching electric circuits comprises a contributory switch (3), a main switch (2), and a flexible element (4). The contributory switch (3) and the main switch (2) are connected electrically in series, the contributory switch (3) and the main switch (4) each comprise at least one movable contact and the flexible element is connected to one movable contact of the contributory switch, a first contact (5a), and one movable contact of the main switch, a second contact (6a).

Abstract: The invention relates to a power supply arrangement of a transport system. The transport system comprises a motor for moving the transport appliance; a power supply circuit of the transport system, for supplying power between the power source of the transport system and the motor; a power controller of the energy storage, which power controller comprises at least one controllable switch; an energy storage, which is connected to the power supply circuit of the transport system via the power controller of the energy storage; and also a power control, which is fitted to control the aforementioned at least one controllable switch of the power controller of the energy storage, for adjusting at least one electrical magnitude relating to the power supply between the power supply circuit of the transport system and the energy storage. The power controller of the energy storage is fitted to discharge the aforementioned energy storage with a power limitation.

Abstract: The invention relates to a power supply arrangement of a transport system. The transport system comprises a motor for moving the transport appliance; a power supply circuit of the transport system, for supplying power between the power source of the transport system and the motor; a power controller of the energy storage, which power controller comprises at least one controllable switch; an energy storage, which is connected to the power supply circuit of the transport system via the power controller of the energy storage; and also a power control, which is fitted to control the aforementioned at least one controllable switch of the power controller of the energy storage, for adjusting at least one electrical magnitude relating to the power supply between the power supply circuit of the transport system and the energy storage. The power controller of the energy storage is fitted to discharge the aforementioned energy storage with a power limitation.

Abstract: A drive system for an elevator includes a drive machine by means of which the for moving and supporting an elevator car. The primary circuit of a linear motor is permanently fitted to a wall of a building while its secondary circuit is fitted in conjunction with the elevator car and moves with the elevator car. Pressurized air is supplied between the primary and secondary circuits of the reluctance-type linear motor to maintain an air gap between them.

Abstract: An operating panel (5) for an elevator car, containing car call buttons (7), signalling devices and other signs representing information. The control panel of the elevator car is replaced with a touchscreen display (1) incorporating a passage control feature. The touchscreen display (1) is also used as a maintenance tool for the checking of elevator equipment.

Abstract: A procedure and an apparatus for converting a first alternating voltage into a second alternating voltage with respect to frequency and amplitude by means of first (1) and second (2) bridges having switches (T.sub.1 . . . T.sub.12), and a resonant circuit (3) connected between the bridges. The invention also relates to the use of a frequency converter for the control of a motor. The voltages of a supplying network and the voltages of a load (M) are connected across the resonant circuit (3) in an alternating fashion by means of bridge switches (T.sub.1 . . . T.sub.6) and bridge switches (T.sub.7 . . . T.sub.12), respectively. The voltages are alternately connected across the resonant circuit for a period equal to respective half cycles of the characteristic frequency of the resulting resonant circuit formed. When power is supplied, a bridge change is effected after each period.

Abstract: The invention relates to an elevator comprising an elevator car unit containing at least two elevator cars and to a procedure for controlling the elevator. According to the invention, at least one elevator car can be moved vertically within the elevator car unit relative to its frame. The procedure is characterized in that prior to start-up, the exact distances between landings are measured and stored in memory. The distance data corresponding to the control instruction according to a unit call or car call is then determined, and based on this data, the elevator car unit is caused to move in the shaft to a position corresponding to the call. At least one of the elevator cars is caused to move relative to the frame of the unit to a position corresponding to the distance between the floors in question.

Abstract: Procedure for regulating the stator flux and torque of an asynchronous motor by vector control in an imaginary space vector coordinate system, in which procedure the absolute value (.vertline..PSI..sub.s .vertline.) of the stator flux and the torque (M) are determined in said coordinate system, and in which procedure the calculation coordinates are in such a position that the rotor flux (.PSI..sub.r) is at least close to the real axis. In the procedure of the invention, the absolute value of the stator flux (.vertline..PSI..sub.s .vertline.) is regulated by means of the real part (u.sub.sr) of the stator voltage and the torque (M) by means of the stator frequency (f.sub.s). The calculation coordinates are held in said position by adjusting the imaginary part (u.sub.si) of the stator voltage.

Abstract: Method and apparatus for the measurement and tuning of an elevator system including at least one elevator having an elevator car and its control and driving equipment. The method uses at least one computer connected to the system. The elevator system is measured and tuned using virtual measuring and tuning components operated by programs of the computer.

Abstract: In a method of and apparatus for connecting a storage battery to an elevator inverter, the storage battery being connected to a d.c. circuit of the elevator inverter power stage, a voltage in the d.c. circuit is higher than the battery voltage. Power flows bidirectionally from the storage battery to the d.c. circuit and vice versa. When power is flowing from the storage battery to the d.c. circuit, the battery voltage is matched to the voltage in the d.c. circuit by the aid of a semiconductor switch, by means of which an energy store is charged, and a diode, by which the energy in the energy store is discharged into the d.c. circuit. When power is flowing from the d.c. circuit to the storage battery, the voltage of the d.c. circuit is matched to the battery voltage with the aid of a second semiconductor switch, by means of which the energy store is charged, and a second diode, by which the energy in the energy store is discharged into the storage battery.

Abstract: The invention relates to a method and means for determining the position of an elevator car on the principle of floor selection by means of a pulse train, whereby the position of the elevator car is determined on the basis of a pulse count indicating the elevator's speed. The achieve a more reliable pulse count based floor selection system which is suited for use with any type of elevator, the pulses required for calculating the elevator position for floor selection are obtained from an acceleration sensor placed on the elevator car, the output signal of which is integrated so as to obtain a voltage representing the speed of the elevator car, said voltage being converted into a pulse train whose frequency is dependent on the speed of movement of the elevator car.

Abstract: An apparatus for controlling a three-phase inverter supplying the a.c. motor of an elevator, the inverter having a power stage implemented with semiconductor switches, and the apparatus comprising an electronic control unit for producing a velocity reference value and a tachometer generator for producing an actual velocity value, voltage measuring elements for measuring a.c. voltages at the inverter output, and pulse width modulators and drivers for controlling the semiconductor switches in the inverter's power stage with control signals derived from the pulse width modulators. With the apparatus of the invention, fast control of the control voltage is achieved. Moreover, simpler voltage measuring elements may be used instead of current measuring elements.

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.

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: 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: The invention concerns, first, a signalling procedure for a lift, whereby the control system and the users of the lift are informed on lift calls and the state of the lift, e.g. position, movement and availability, by using serial communication between the control system computer and the actuating and signalling means in the lift car and on each floor level, and, second, a signalling system applying the said procedure. To avoid abundant and complicated wiring and to increase standardization in the design of the lift system main panel and call button stations, the signalling system of the invention employs the polling principle in its internal communication, whereby data are transmitted bi-directionally using digital series loops, one of which connects the devices in the lift car, controlled by and communicating via a microprocessor, another connects the corresponding shaft and door devices, while a third loop is used for communication with the external world.

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.