Figure 2-25. Deceleration Control Curve - Epson C117001-N - DFX 5000+ B/W Dot-matrix Printer Service Manual

Operating Principle
1. It causes the carriage to accelerate.
Because the control circuit measures time periods with the encoder signal, when the carriage
2.
speed reaches SP1, it changes to the next sequence (SP1 - SP2).
- SP2
1. The DFX-5000+ printer has a table programmed into its main program ROM to determine the
duration of the acceleration pulses. This table is called the duty data table. Duty data is divided
into ten sections, plus Dutymin. Section 1 is the largest, and Dutyti represents the minimum
duty data for acceleration control. Pulse width modulation (PWM) determines each section
number. For each section, the carriage motor driver is turned on part of the time and off part of
the time.
2. When the carriage speed reaches SP1, the printer uses the acceleration driving mode, based on
the duty data, and the rest of the time, it uses Deceleration driving mode 2. (Refer to Table 2-5.)
3. During this time the control circuit measures time periods using the encoder signal, and
controls the following:
carnage speed reaches SP2, the next sequence (SP2-) takes effect.
When the carriage speed reaches SP2, PI control oversees the carriage speed.
Deceleration control provides smooth deceleration and prevents rapid vibration.
B

Figure 2-25. Deceleration Control Curve

Note: In Figure 2-25, the deceleration curve is labeled A and the driving modes are labeled B.
1,2, and 3 indicate the PWM control section number.
2-28
1
msec
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: :
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Rev. A