Specifications

2 - 10
2.5 HOME SWITCH
The home switch is a push-open type mechanical switch, which switches “OFF”
when the head is at the home position (left end). The switch has two functions. The
first is to detect the home position when the head stops there. Upon returning to
the home postion, the home switch switches from “ON” to “OFF”, and brakes are
applied to stop the motion of the print head.
The second function is it is used as reference point for starting the counting of the
print timing signals. As the head begins to move to the right from the home position,
the home switch switches from “OFF” to “ON”, at which point counting of the print
timing signal begins (TG signals after waveform shaping).
(1) Contact resistance
5
max. (measuring current: 50
µ
A)
(2) Current
1.0 mA max. (5.0 VDC)
(3) OFF-to-ON detection
Figure 2-6 OFF-to-ON Detection
100
µ
s
2ms
This swtich has the characteristics that the ON state exists for more than 100
µ
s
within 2 ms of when the home switch switches from OFF-to-ON. Do not detect the
switch until after 1-line has printed after detection of the first ON detection.
(4) ON-to-OFF detection
Figure 2-7 ON-to-OFF Detection
2ms
450
µ
s
This switch has the characteristics that the OFF state exists for more than 450
µ
s
within 2 ms of when the home switch switches from ON-to-OFF. Do not detect the
switch for 10 ms after detection of OFF.