Browse Prior Art Database

Dynamic Control Method and Apparatus for Drill Machines

IP.com Disclosure Number: IPCOM000113021D
Original Publication Date: 1994-Jun-01
Included in the Prior Art Database: 2005-Mar-27
Document File: 1 page(s) / 103K

Publishing Venue

IBM

Related People

Iwano, K: AUTHOR [+3]

Abstract

Disclosed is a program that optimizes a velocity parameter of a printed-circuit-board drilling machine. It dynamically changes the vertical velocity, or the drill-down velocity, according to the characteristics of the drilling route, so that the total drilling time is minimized, while keeping the probability of bit breaks during the processing of ellipsoidal holes, as small as possible. The Figure shows an example of an ellipsoidal hole (Fig. 1a) made up of five drill holes (Fig. 1b).

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Dynamic Control Method and Apparatus for Drill Machines

      Disclosed is a program that optimizes a velocity parameter of a
printed-circuit-board drilling machine.  It dynamically changes the
vertical velocity, or the drill-down velocity,  according to the
characteristics of the drilling route, so that the total drilling
time is minimized,  while keeping the probability of bit breaks
during the processing of ellipsoidal holes, as small as possible.
The Figure shows an example of an ellipsoidal hole (Fig. 1a) made up
of five drill holes (Fig. 1b).

      As input, the program receives an NC data file consisting of
the coordinates of drill holes arranged in the order of the drilling
route.  It adds commands at appropriate positions in this sequence to
change the vertical velocity value of a drill machine, and produces
an NC file as output.  The program has three kinds of velocity value,
VMAX, VMID, VMIN (VMAX > VMID > VMIN ), and also one critical value,
EC, which evaluates the imbalance of pressure imposed on a drill bit
during the processing of overlapping holes.

      The program determines the velocity V as follows.  First it
sets the velocity to the maximum value (V = VMAX) at the beginning of
the NC data.  For each hole Xi, it searches for the nearest hole Xl
to its left among the holes already drilled, and stores the distance
between Xi and Xl as the variable Dl.  Similarly, it calculates the
distance from Xi to the nearest drilled hole to its ri...