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Turning/bending
motor
Cutting cylinder
Feeding motor
Rod
Drag
Rod
Entrance
Help to
Cut
Feeding
Electrovalve
Turn
Electrovalve
Cutting
Electrovalve
Proportional
Electrovalve
Pump 2
Pump 1
Figure 10: DESA 14 Hydraulic Diagram.
At present DESA 14 machine is controlled and commanded by a microcontroller based
programmable control device. Such control equipment operates moving parts of the machine in a
programmed sequence to obtain the required stirrup shapes.
The control device includes three types of programs to produce different types of stirrups:
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Stirrup programs: to produce polygonal stirrups (stirrups with straighten sides) and mixed
stirrups (stirrups with straighten and rounded sides).
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Hoop programs: A hoop consists of two straighten sides and one rounded section.
•
Incremental programs: to produce incremental stirrups, which are groups of polygonal
stirrups with the same shape but different dimensions.
The current storing capacity is 140 programs: 40 for hoops, 90 for mixed stirrups and 10 for
incremental stirrups. The main components of such control system are:
•
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User-interface elements:
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Liquid Crystal Display (LCD). Resolution of 240 x 128 points.
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Keyboard with 20 tactile keys.
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Operation mode selectors (AUTO, SEMI, STOP and GO).
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Manual operation selectors and machine’s status lamps.
Eight electronic modules:
− Boards Nº1, Nº2 and Nº3 are three power boards to operate the directional electrically
operated valves.
− Board Nº4 to monitor the position of the cutting cylinder. Receives the signal provided by
position sensor in the cutting cylinder. This board also commends the proportional electrically
operated valve.
− Board Nº5 to monitor signals from the incremental and absolute encoders.
− Board Nº6 that receives the signals coming from the front panel controls.
− Board Nº7 that provides the signals for the power boards Nº1, Nº2 and Nº3.
− Board Nº8 is the control CPU (Central Processing Unit).
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FUSE Application Experiment Nº 29826