Panasonic SA-HT440P Service Manual page 36

Step 1 Rotate open lock gear in the direction of arrow. (Anti-clockwise)
Step 2 Release claw of open lock gear, remove open lock gear in the direction of arrow.
10.16.2. Disassembly of the Close Lock Gear
- Follow (Step 1) to (Step 3) of Item 10.5.
Step 1 Remove 1 screw.
Step 2 Hook close lock spring to claw (a).
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