Patent ID: 7293500
Filing Date: 2007-11-13
Classification: B30B

Abstract:
1. A pressing apparatus characterized by comprising: a base; a support plate that is held in parallel to the base via plural guide columns vertically provided on the base; a slider that can slide on the guide columns to move up and down between the base and the support plate; a first motor for fast feed that is attached to the support plate and drives the slider up and down fast; and a second motor for pressing that moves the slider up and down to press a work piece, and in that: the pressing apparatus includes: an encoder for the first motor that detects rotation of the first motor; an encoder for the second motor that detects rotation of the second motor; and a single position detector, which measures movement of the slider, provided for a set of the first motor and the second motor, a servo module for controlling the first motor, and servo module for the first motor calculates an instruction based on position information giving a position where the first motor should be placed according to elapse of driving time of the first motor; a servo driver for the first motor controls the first motor, and the servo driver for the first motor drives the first motor according to an instruction from the servo module for the first motor and a signal from the encoder for the first motor, a servo module for controlling the second motor, and the servo module for the second motor calculates an instruction based on position information giving a position where the second motor should be placed according to elapse of driving time of the second motor; a servo driver for the second motor controls the second motor, and the servo driver for the second motor drives the second motor according to an instruction from the servo module for the second motor and a signal from the encoder for the second motor, and in the position detector, information giving a position of the slider, which is obtained from a signal from the single position detector during a period from start of the first motor until start of a press stroke period by the second motor, is reset and information giving a position of the slider at the time of start of the press stroke period by the second motor is set as a starting point value.