摘要:
A controller for a servomotor capable of improving accuracy of positioning and quality of a machined surface by switching modes of correction of a position command or the like, and reducing a shock at the time of switching. A correction amount generating section obtains a correction amount based on a value of a correction factor such as machine temperature. When the external signal is in ON state, a position command or the like is corrected by the correction amount obtained by the correction amount generating section and sent via switches. A correction amount holding section holds the correction amount obtained by the correction amount generating section. When the external signal turns to OFF state, the connection of the switches is changed so that correction is performed by the correction amount held in the correction amount holding section. When the connection of the switches is changed, the correction amount does not change rapidly, so that the machine does not suffer a shock. In positioning, the external signal is turns to ON state, so that the positioning is carried out accurately by performing correction by the correction amount sent from the correction amount generating section. When a high-quality machined surface is required, the external signal is turned to OFF state so that the correction amount does not change to achieve improvement in the quality of a machined surface.
摘要:
A motor drive apparatus 1 having a dynamic braking circuit 5 for producing a deceleration torque utilizing a braking force caused by a synchronous motor 4 acting as a generator when the synchronous motor 4 is deenergized, is equipped with a dynamic braking circuit fault detection capability, and comprises: a DC power supply 2 which is obtained by rectifying input AC power; voltage application means 2, 3, 10, 11 for applying a voltage to the windings of the synchronous motor 4 and to the dynamic braking circuit 5 for a predetermined length of time by switching power transistors A to F connected to the DC power supply 2; current detection means 6 for detecting the value of a current flowing from the power transistors A to F; and fault checking means 11 for checking the dynamic braking circuit 5 for the presence or absence of a fault, based on the current value detected by the current detection means 6 and on a predefined threshold value. With this configuration, detection of faults in the dynamic braking circuit is accomplished without requiring the addition of a contact signal or a control circuit.
摘要:
A motor drive includes a dynamic braking circuit for producing a deceleration torque utilizing a braking force caused by a synchronous motor acting as a generator when the synchronous motor is deenergized. The motor drive apparatus is equipped with a dynamic braking circuit fault detection capability, a DC power supply which is obtained by rectifying input AC power, voltage application function for applying a voltage to the windings of the synchronous motor and to the dynamic braking circuit for a predetermined length of time by switching power transistors connected to the DC power supply, current detection unit for detecting the value of a current flowing from the power transistors, and fault checking unit for checking the dynamic braking circuit for the presence or absence of a fault, based on the current value detected by the current detection unit and on a predefined threshold value.
摘要:
A controller for a servomotor capable of improving accuracy of positioning and quality of a machined surface by switching modes of correction of a position command or the like, and reducing a shock at the time of switching. A correction amount generating section obtains a correction amount based on a value of a correction factor such as machine temperature. When the external signal is in ON state, a position command or the like is corrected by the correction amount obtained by the correction amount generating section and sent via switches. A correction amount holding section holds the correction amount obtained by the correction amount generating section. When the external signal turns to OFF state, the connection of the switches is changed so that correction is performed by the correction amount held in the correction amount holding section. When the connection of the switches is changed, the correction amount does not change rapidly, so that the machine does not suffer a shock. In positioning, the external signal is turns to ON state, so that the positioning is carried out accurately by performing correction by the correction amount sent from the correction amount generating section. When a high-quality machined surface is required, the external signal is turned to OFF state so that the correction amount does not change to achieve improvement in the quality of a machined surface.
摘要:
A die cushion controller, for driving a die cushion, disposed in opposition to a slide of a press machine, by controlling a servo motor, including: a pressure command portion which prepares a pressure command value for exerting a predetermined pressure to a press material disposed between the slide and the die cushion; a pressure detecting portion which detects an actual pressure exerted on the press material; a speed correction value preparing portion which prepares a speed correction value by multiplying a differential value of the pressure command value prepared by the pressure command portion by a coefficient; and a first speed command portion which prepares a speed command value to be instructed to the servo motor based on the pressure command value prepared by the pressure command portion, the actual pressure detected by the pressure detecting portion, and the speed correction value prepared by the speed correction value preparing portion.
摘要:
An acceleration detection unit for detecting acceleration is mounted on a driven body. When a previous block is a positioning command, the system waits till the detected value of acceleration detected by the acceleration detection unit becomes equal to or less than a set value αs after the distribution of the movement command of the positioning command is ended. If the detected value of acceleration becomes equal to or less than the set value αs, the distribution of the movement command of the next block is started. Because the cutting feed, etc., is started after the detected value of acceleration has become equal to or less than the set value αs and the vibrations stopped, machining can be conducted with high accuracy.
摘要:
A control apparatus for controlling a die cushion mechanism including a servo-motor as a drive source and producing a force adapted to be applied outside. The control apparatus includes a force commanding section for commanding a force to be produced by the die cushion mechanism; a force detecting section for detecting a force produced by the die cushion mechanism; a force controlling section for executing a force control on the servo-motor, based on a force command value commanded by the force commanding section and a force detected value detected by the force detecting section; and an abnormality preventing section for preventing, in association with a control state of the servo-motor, the die cushion mechanism from producing an abnormal force.
摘要:
A method for changing a force control gain expressed as a ratio of force error to velocity command value in a control circuit performing a force control of a servo motor driving a die cushion disposed opposite to a slide in a press machine. The method includes: obtaining a difference between a displacement of the slide and a displacement of the die cushion in a state in which the slide and the die cushion collide with and are exerting force on each other; detecting the force when the difference of the displacements is obtained; calculating a spring constant of a structural portion based on a proportionality between the difference of the displacements and the force, when regarding the structural portion including the slide and the die cushion as an elastic structure; and changing the force control gain based on the spring constant using a fixed proportionality that exists between the force control gain and a reciprocal of the spring constant.
摘要:
A control apparatus for controlling a die cushion mechanism including a servo-motor as a drive source and producing a force adapted to be applied to a slide in a press machine. The control apparatus includes a force commanding section for commanding a force to be produced by the die cushion mechanism; a force detecting section for detecting the force produced by the die cushion mechanism; a motor-speed detecting section for detecting an operating speed of the servo-motor; a slide-speed detecting section for detecting a moving speed of the slide; and a force controlling section for executing a force control on the servo-motor, based on a force command value commanded by the force commanding section, a force detected value detected by the force detecting section, a motor-speed detected value detected by the motor-speed detecting section and a slide-speed detected value detected by the slide-speed detecting section.
摘要:
A servo motor controller having: a frequency identification section that performs analysis based on a frequency response method and identifies the frequency of a disturbance exhibiting a specified phase lag; an input/output gain identification section that identifies the input/output gain at the frequency identified by the frequency identification section; and a magnification factor resetting section that resets an adjustment magnification factor by performing a specified operation on a ratio between the identified input/output gain and a specified target value of the input/output gain.