Mitsubishi Denki Kabushiki Kaisha

Toshiaki Ishii

Kazumasa Ito

Kazuhiro Yoshikawa

Eiki Watanabe

Masamoto Mizuno

Hiroyuki Ikejima

Kazuhiko Sugita

Takeshi Furuhashi

Shigeru Okuma

Shigekazu Sakabe

Tooru Tanahashi

Makoto Tomidokoro

Takehiko Kubota

Takanobu Masaki

Sueo Okabe

Shuzo Mitsui

Masanori Yasue

In an elevator system, first and second car carrying bases move up and down along first and second segments of a hoistway, respectively. First and second support members are located on the first and second car carrying bases, respectively. A car is moved up and down within the hoistway while being selectively supported by the first or second car carrying base. The first and second car carrying bases are arranged so as not to overlap each other when projected on a horizontal plane. Each car support member can shuttle between a support position and a nonsupport position, the support position being a position at which the car support member supports the car by projecting into a moving path of the car and the nonsupport position being a position at which the car support member is retracted from and is outside of the moving path of the car.

Elevator system

This invention is concerned in a secondary conductor for an elevator-driving linear induction motor in which, in connecting secondary conductor members to one another, adjoining portions of secondary conductor members are cut and engaged with one another by lapping them over each other, and the edge portions of them are joined at least on one side with a fastening member or by pressure joining or by welding, whereby the difficulty is eliminated that the secondary conductor members, being bent for instance, are raised to form a step therebetween, so that the secondary conductor members are brought into contact with or struck against the primary windings of the linear induction motor, and the secondary conductor members and the primary windings are damaged.

Secondary conductor of an elevator-driving linear induction motor

A linear motor elevator system comprising a sheave disposed in the upper portion of an elevator hoistway, a length of rope wound around the sheave, a movable member connected to said rope, a primary winding disposed only on a first side of said movable member and a secondary conductor extending within and along the hoistway in association with said primary winding to constitute a linear motor. The system may comprise a brake unit disposed on a second side of said movable member which is opposite to said first side and a guide rail disposed within said hoistway for being engaged by said brake unit.

Linear motor elevator system

A controller for a ropeless elevator, includes: a cross induction line cable arranged along the hoistway; an exciter provided on the car side to generate sinusoidal waves for positional detection in the cable; a movement amount detector provided on the car side to detect a car movement amount; a data calculator provided on the car side to calculate data on car speed and on secondary-conductor magnetic pole phase from the movement amount detected by the movement amount detector; a data transmitter provided on the car side to utilize the cross induction line cable in transmitting the data calculated by the data calculator to the building side; an induction radio circuit provided on the building side to utilize the cable in receiving data from the data transmission device and calculate the initial phase of the secondary conductor from the sinusoidal waves generated in the cross induction line cable; and an inverter control circuit provided on the building side to interpolate the initial phase calculated by the induction radio circuit on the basis of the magnetic pole phase received by the induction radio circuit and control the inverter on the basis of the calculated car position and the car speed data received by the induction radio circuit.

Controller for ropeless elevator

The present invention provides a linear motor driven elevator apparatus which enables a decrease in the thrust variation at the passage of primary windings of a linear induction motor loaded on a car or a balance weight through joints of secondary conductors and which can prevent an unpleasant impression from being given to the passengers. In the elevator apparatus, each of the connections of the secondary conductor members of the linear induction motor serving as a drive source for vertically driving an elevator car has a structure in which each of the secondary conductor members is notched to about half of the thickness thereof, and the notch portions are superposed. The length of each of the notch portions is set to a value greater than the pole pitch of the primary windings of the linear induction motor, and the set heights of the joints are different from each other.

Joining segments of the secondary in a linear motor driven elevator

A linear motor elevator includes: a multitude of primary side coils mounted on the hoist way along the whole hoist path, and vertical columns of permanent magnets constituting the secondary side magnets mounted on the elevator car. The polarity of the permanent magnets alternate both horizontally across the columns and vertically along respective columns. When the elevator car is displaced horizontally in a direction perpendicular to the hoisting direction of the elevator car, a circulating current producing a magnetic flux that counterbalances the variation of the flux caused by the displacement flows through each primary side coils opposing the permanent magnets on the elevator car. Thus, the position of the elevator car within the hoist way is automatically adjusted in accordance with the null-flux method.

Linear motor elevator device with a null-flux position adjustment

A linear induction motor for an elevator which includes a secondary, stationary element having a body formed with a plurality of iron-core mounting holes arranged longitudinally of the body at a certain interval, and iron cores disposed in the holes. The stationary, secondary element allows magnetic flux flowing therethrough to pass through the iron cores, thereby reducing the dimension of the total magnetic gap in the motor. Furthermore, the combination of the iron cores in which eddy currents flow with difficulty and the body along which eddy currents tend to flow makes it possible to reduce the ineffective eddy currents.

Linear induction motor for elevator

A linear motor elevator includes permanent magnets 4 mounted on a pair of wing-shaped support members 21 secured on and projecting sideways from the right and the left side walls 3a of the elevator car 3. The polar axes of the permanent magnets 4 are arranged in the direction of the thickness of the support members 21, such that both the north and the south poles of the permanent magnets 4 are exposed on the front and the back surface of the support members 21 and hence are utilized effectively for producing driving force (thrust) for the elevator car 3. Each one of the right and the left side coils 20a and 20b of the primary side coils 20 for forming vertically translating magnetic field is bent at the middle to form two horizontally extending branches, such that the primary side coils 20 sandwich the permanent magnets 4 across predetermined gaps in the direction of polar axes of the permanent magnets 4, when the elevator car 3 passes by the primary side coils 20. Thus, the strong attractive force acting on the permanent magnets 4 from the primary side coils 20 does not act on the cage structure of the elevator car 3.

Linear motor elevator with support wings for mounting secondary side

A position control system for elevators including a plurality of pulse encoders which independently generate pulse signals in accordance with the movement of a cage. The pulse signals are respectively counted, and the operation of the cage is terminated when a difference in counted results between the encoders has exceeded a predetermined value. Thus, the cage can continue to operate even if there is a small difference between the counted results, and, when any of the pulse encoders malfunction, which triggers a substantially larger difference in counted results, the cage is controlled to stop the operation.

Position control system for elevator

A speed control apparatus for an elevator in which a temperature detector for detecting the ambient temperature of an induction motor is disposed, and an arithmetic unit employing a microcomputer is additionally furnished with the function of evaluating the component of temperature rise of a rotor and obtaining the resistance value of the rotor by the use of this component of temperature rise and the temperature detection signal of the temperature detector, to evaluate the optimum instantaneous current command by the use of the temperature-compensated resistance value, whereby the overvoltage and the insufficient torque of the induction motor can be obviated.

Speed control apparatus for elevator

Collision impacts between meshing gears in a speed reduction mechanism 11 of an elevator system due to backlash during transitions between power/driving and regenerative/driven modes of operation are reduced by detecting the actual or approaching separation of the gear teeth, and in response thereto temporarily reducing the motor torque to correspondingly reduce the equalized relative speed difference between the input and output shafts of the mechanism. Tooth separation may be detected by sensing a difference in amplitude between signals proportional to the input and output shaft speeds, equalized in accordance with the gear ratio, or by sensing a polarity change in the motor drive current. The motor torque may be reduced by the relay controlled switching of resistors 40, 43 in a speed controller to thereby convert the function of an operational amplifier 45 therein from a first order time lag circuit to an integrator.

Method and apparatus for reducing gear backlash impacts in an elevator

An ac to dc power conversion apparatus employing commutated thyristors has a series circuit comprising a capacitor 8 and an impedance element 9 connected at the input side of a thyristor conversion unit 4. The capacitor reduces notch voltages generated during the commutation of the thyristors, and the impedance element prevents the capacitor from resonating with other inductive reactances in the circuit. A switching device 10 is connected in parallel with the impedance element, and is closed during the commutation of the thyristors to maximize the notch voltage reduction.

Thyristor power converter with switched impedance

A failure detection device for a convertor which converts alternating current into a direct current through a plurality of rectifying thyristors. The waveform of the output direct current of the convertor is detected and is supplied to a band-pass filter which selectively passes the harmonic component which has a frequency corresponding to that of the AC voltage source for the convertor. The existence of the component of this frequency is characteristic of an occurrence of a failure within convertor. The amplitude of the component passing through the filter is then detected by a zener diode, and a failure signal is generated when the amplitude exceeds a predetermined level.

Thyristor convertor failure detection device

A speed control apparatus for an elevator wherein a current command signal for controlling the firing angle of dual thyristor converters is supplied through a filter circuit. On switching from one converter to the other pursuant to reversing the elevator direction, the filter circuit is reset to bring the current command signal momentarily to zero, after which it rises smoothly in a positive or negative direction together with the elevator motor armature current.

An elevator speed control device in which the cage of the elevator can be stopped at a desired floor with a high accuracy without increasing the capacity of power supply equipment to compensate for periods of low AC source voltage. A detecting circuit produces an output signal in response to the generation of a deceleration instruction signal. This signal is converted into a short duration pulse signal which is used to set the output of an integrator included in the control circuit loop to a predetermined value.

Growing community of inventors

Inazawa, Japan

Toshiaki Ishii