Panasonic VDR-M30PP Service Manual page 12

(1) Lock mechanism of disc loading block (lock unit)
Since the structure of disc loading block in VDR-M30 is different from that of the lock unit in
previous models, it will not open unless a power supply (battery or AC adapter/charger) is
connected.
The lock arm in VDR-M30 lock unit is driven by the DC motor controlled by a microprocessor (see
Fig. 3-1-1).
The lock arm is usually in locked status: When the DISC EJECT button is pressed, the DC motor
drives the lock arm in the release direction.
DISC
EJECT
button
The lock arm in lock units of previous models is mechanically coupled with the DISC EJECT button
via a solenoid , except when disc is being accessed (see Fig. 3-1-2).
*1
The solenoid is controlled by the current supplied from camera control microprocessor.
While the disc is being accessed, the camera control microprocessor outputs the current and controls
the solenoid to release the coupling between DISC EJECT button and lock arm, so that the disc
loading block does not open.
If no power supply is connected, the camera control microprocessor will not operate, and the
solenoid will not release the coupling.
*1: A device that converts electrical energy to mechanical energy, using the magnetic force that is generated
when current flows to electromagnetic coil.
In status other than
Lock unit
Solenoid
Camera
control µP
Camera
SH µP
control µP
Fig. 3-1-1 Lock Unit in VDR-M30
disc access
Lever
Open
Lock arm
Fig. 3-1-2 Lock Unit on Previous Models
µP in disc
drive unit
During disc access
DISC
EJECT
Lock unit
button
Solenoid
Case
Camera
control µP
Lock unit
Spring
DC
Release
M
motor
direction
Lock arm
DISC
Lever
EJECT
button
Open
Lock arm
Case
Current