摘要:
An apparatus and method are disclosed for controlling the motion of a machine system so as to cut individual lengths from a web having graphics on predetermined web positions and which allows the use of an inexpensive AC induction motor. An AC induction motor (42) has an output power shaft for imparting the motive force necessary to drive the machine system, such as a web feeding system. A sensor (29) is operatively coupled to the AC motor for determining the position of the motor during system operation. A controller (26) is operatively connected to the sensor and motor and forms a closed loop control circuit. The controller changes the feedback loop characteristics of the closed loop control circuit during a stop, hold or start condition of the motor. By adding an externally generated compensating signal to the input of the feedback loop, the controller also minimizes acceleration error. The controller also limits the value of a signal reaching the feedback loop of the control circuit to a given maximum value so as to eliminate any over-reaction of the system, while allowing a signal having less than a given threshold value to proceed unaffected to the feedback loop.
摘要:
A positioning device comprising a motor, a driver for driving the motor, and a digital signal processor for performing an operation for positioning control for the motor.
摘要:
An apparatus for controlling an elevator door 12 includes a three phase AC motor 26 that receives control signals from a controller 18. The signals are issued at control points along a speed versus distance profile map 24 that represents the control points as a percentage of the total distance to be travelled by the elevator door 12. The total distance of door travel in one direction is measured be counting the number of pulses generated by an incremental encoder 32 during a training run wherein the door is moved between its extreme positions at a constant speed. The number of pulses counted is then normalized to represent 100% of the distance travelled. During operation, the pulses are counted whenever the elevator door 12 is in motion and control signals are issued based upon the number of pulses counted.
摘要:
A single cycle positioning system utilizing a three phase wye connected induction motor (10) includes a three phase inverter (28) and a microprocessor (20) for controlling the inverter to generate three phases of power. Pulse width modulation techniques are utilized and in response to a start signal the frequency of the power to the motor is increased up to a running frequency, and in response to a stop signal the frequency of the power applied to the motor is decreased along with a corresponding reduction of the voltage applied to the motor.
摘要:
A main shaft motor control method capable of carrying out contour machining with a high accuracy. A vector control processor performs speed loop processing to obtain a torque command (Tc). It is also adapted to carry out (S4, S7) a vector control operation in accordance with a magnetic flux command (Ζc), which is set to a predetermined constant level (CFΖ), when it judges that the main shaft motor is driven in a contour control mode, whereby irregularity in speed of the motor and vibration thereof which are ascribed to a delay of the actual magnetic flux in the main shaft with respect to the magnetic flux command are prevented to enable contour machining to be carried out with a high accuracy. In a normal speed control mode or a tool change orientation mode, a vector control operation is carried out (S4-S6, S8) in accordance with a torque command (Tc) and its maximum value (Tcmax), a maximum magnetic flux command (Ζcmax) determined according to the rotational speed of the motor, and a magnetic flux command (Ζc) determined on the basis of a minimum magnetic flux command (NRΖcmin, ORΖmin).
摘要:
A digital servo-control apparatus which controls the rotation of a servomotor on the basis of a digital position command value representative of a target position and a digital position feedback value output from a position detecting device. The apparatus comprises a device for calculating a feedforward value at intervals of a predetermined period on the basis of the amount of change of the position command value, a device for delaying the position command value by a period of time corresponding to an operation delay in the feedforward value calculating device, a device for calculating a velocity command value by adding the feedforward value to a deviation of the position feedback value from the position command value delayed by the delay device, and a device for driving the servomotor according to the velocity command value determined by the calculating device.
摘要:
L'invention se rapporte à un procédé de régulation de la vitesse de rotation d'un moteur électrique à courant alternatif entre deux positions angulaires extrêmes du rotor. Ce procédé est caractérisé en ce que, à l'initialisation, on détermine le nombre théorique (N) de périodes complètes (T) du courant alternatif (i) devant alimenter le moteur (1) pour l'entraîner sur un tel déplacement angulaire, on mémorise ce nombre théorique (N), en fonction de la position chronologique (X) de ces périodes (T) complètes dans leur nombre théorique total (N), on élabore une table des variations de l'alimentation du moteur à prévoir pour respecter une consigne de vitesse prédéterminée, lors de l'utilisation, on compte le nombre réel (N') instantané des périodes complètes du courant alternatif depuis une position extrême (EI) vers l'autre position extrême (EF), en fonction de la position chronologique (X) du nombre réel (N') on adapte l'alimentation du moteur sur la valeur donnée par la table pour le nombre théorique correspondant. Application à l'industrie du matériel électrique et électro-technique.
摘要:
Method for obtaining a predetermined position for a satellite antenna, whereby a controller (9) is caused to transfer information to a velocity controller (3), which in turn is being caused to transfer information to a current regulator (4), being caused to transfer current to a motor which is intended for setting the desired position of the satellite antenna. The invention is characterized in that an electrical motor (5) is caused to receive current from the current regulator (4) so that the electrical motor (5) is caused to turn a predetermined angle during a predetermined time interval, in that an angle sensor (6) is positioned on the satellite antenna and is caused to read an absolute angle or an angular displacement of the satellite antenna, and in that the angle sensor (6) is connected to the controller (9) so as to create a feedback loop. The present invention also relates to an automatic control system.
摘要:
The invention concerns a safety device for power operated closing systems, such as industrial, commercial, garage, gate electromechanical systems and similar, where the closing system has at least one moving part driven by an electric motor using mains supply voltage and frequency current, governed by an electronic control panel. As a safety measure, the device makes us of an encoder or an encoder and inverter in combination, to generate signals to the electronic panel indicating the position and speed of the moving part so as to control and limit the dynamic or impact force of the latter on encountering an obstacle during its travel.