Music Perforator
By Ed Schmidt
Jody asked if I would provide more information on my roll perforating system. Well here goes.
The machine consists of a single punch and die set (the set is intercahangeable) that is mounted on a high strength aluminum U shaped carrier with a 16" throat. The carrier is mounted on precision ball bearings and is moved transversally across the paper by a stepper motor and lead screw at a resolution of 0.001". The paper is pulled longitudinally by rubber pinch rollers at a resolution of 0.01". Both axis of the system were originally at 0.01", but I upgraded one with a microstep drive. Eventually I will upgrade both axis to 0.001". After the paper is punched, it passes through rotory cutters to trim the paper to the desired width.
The punch is air driven with a 1" diameter cylinder. One problem encountered in punching large holes for organette music is that occasionaly a small shard of paper will prevent the punch from returning if only a spring return is provided. The simplest solution is to use a double acting air cylinder that drives the punch through the paper and then drives it back to the starting position.
The perforator is also used to copy original music. A series of different tracker bars have been constructed using photo-transistors as the sensing element. I have used two different Texas Instrument devices. One is TIL78 which is .125" in diameter. The other is LS400, which is 0.085" in diameter. I am not sure of the availability or price of either device since it was many years ago that they were purchased. The paper is illuminated with an 18" long GE Lumiline lamp that is run on DC at 60 volts.
All comunication with the computer that controls the reader and the punch is done through a parallel port. The photo-transistors are wired in groups of eight and the data readin a byte at a time until all notes have been read. A parallel output port selects the byte to be read.
At present, I have only been punching music for Organettes, Tanzbar accordians, a few different monkey organs and just starting on spome Rollmonica rolls. As like most of you, I have a full time job, which limits the time that I can devote to roll punching. Originally my two sons were involved, but both have moved away and are persuing other activities. I had planned to retire and devote more time to this activity, but I have a project to finish which will take the next three years.
At one point we considered manufacturing the punching system, but then it was too costly. Now there is not enough time.
Edward Schmidt <eschmidt@erols.com>
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(Message sent Wed 16 Oct 1996, 11:02:14 GMT, from time zone GMT-0400.) |
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