Patent ID: 9669450
Date: 2017-06-06
CPC Classifications: B21D,Y10T

Claim:
1. A method of supplying lubricating oil to a lifter spring by use of a punch tool device, the method comprising: providing a punch tool device having a tubular punch guide vertically movably mounted in a punch mounting hole provided in a punch holder of a punch press; providing a vertically movable punch body inside the punch guide, and including a punch edge section in a lower end portion of the punch body; providing a punch driver above the punch body; providing a punch head on an upper end portion of the punch driver; providing an elastic member between the punch head and the punch guide; supporting a supported section by a lifter spring disposed in the punch holder, and the supported section is provided on an outer peripheral surface of the punch guide; forming a lubricating oil hole in the punch body horizontally in a radial direction, so as to open to an outer peripheral surface of the punch body; providing a communication hole in the punch guide, the communication hole configured to come into and out of alignment with the lubricating hole; providing an emission hole provided at an upper portion of the punch guide, the emission hole configured to emit lubricating oil to pool on an upper surface of the punch body; allowing a striker of the punch press to descend until the striker comes into contact with the punch head of the punch tool device; halting the descent of the striker when the striker comes into contact with the punch head; keeping the striker in the state of being in contact with the punch head without allowing the punch head to descend further; holding the lubricating oil hole and the communication hole provided in the punch guide in a state of being aligned with each other in a straight line; directly supplying the lubricating oil provided from a hole in the striker to the lifter spring from the lubricating oil hole via the communication hole; and transmitting, by the emission hole, the lubricating oil to the lifter spring when the punch body ascends in the punch guide after the punch body is made to descend in the punch guide due to the striking of the punch head by the striker.