How is the cavity depth of an industrial endoscope protective hard latch case set?

150 mm follows a 300 mm coil envelope, with 20 mm clear underneath and 15 mm of foam above; at 130 mm the coil is pinned, at 170 mm it rolls.

How is the 320 N closing force verified?

Both latches are pulled at 30 mm/min and read at peak, never averaged, against a 320 N floor and 400 N ceiling, with a 15% decay limit after 5000 cycles.

Which item comes first after a 1.2 m drop?

The lip step, read with a feeler gauge from 0.05 mm at eight points and held to 0.4 mm; latch force and hinge clearance follow, and corner cracks come last.

What does 30% gasket compression buy?

A 6 mm section compressed to 4.2 mm; under 25% the lip bubbles at 1 m depth, over 40% it eats latch force, and cold set after 24 h at -20°C is capped at 12%.

Industrial Endoscope Case: Cavity Depth and Latch Force

Quick answer: An industrial endoscope protective hard latch case measures 500×390×205 mm outside with a 150 mm deep cavity for a 300 mm coil envelope, and its two latches hold 320 N each while the lip step stays under 0.4 mm after a 1.2 m six-face drop.

Cavity depth and coil allowance of the industrial endoscope protective hard latch case
Closing force and tongue travel of the two hard latches
Hinge stop angle and pin fit along the full-length hinge
Lip step re-check after a 1.2 m six-face drop
Gasket compression and internal humidity after immersion
FAQ

1. Cavity depth and coil allowance of the industrial endoscope protective hard latch case

The industrial endoscope protective hard latch case is built to a 500×390×205 mm outer envelope, a 445×330×150 mm cavity and a 3.4 mm wall, weighing 3.1 kg empty. The 150 mm depth is taken from a 300 mm coil envelope: 20 mm clear underneath and 15 mm left to the tips of the lid foam. At 130 mm the foam pins the coil to the floor and transport vibration runs into the wall root; at 170 mm the coil rolls on a drop and strikes the side ribs.

Depth tolerance is measured only as the distance from cavity floor to foam tips, with foam compression logged on its own line and never folded into the same figure.

Dimension	Value	Reading use
Outer envelope	500×390×205 mm	Aligns with pallet slots
Cavity	445×330×150 mm	Allowance over a 300 mm coil
Wall	3.4 mm	Side dent resistance and boss depth
Empty weight	3.1 kg	One-person carry limit

Cavity depth is moulded in one shot, never milled, so it is tied to foam thickness at the tooling stage. Five units per lot are gauged at four corners and the centre, and a 1.2 mm spread across the five points sends the tool back for review.

2. Closing force and tongue travel of the two hard latches

Two hard latches sit opposite each other, each rated 320 N with 9 mm of tongue travel and a 1.5 mm stainless catch plate. Force is read with a pull gauge at 30 mm/min until the tongue releases, recorded per latch rather than averaged. The 320 N floor keeps the lid from popping open on impact; a 400 N ceiling keeps the catch openable with one hand.

Industrial endoscope protective hard latch case in olive on an assembly bench, gloved worker applying hot glue inside, a black shell open beside it

Tongue travel and lip step move together. At 9 mm the tongue clears the catch lip by 2 mm, the lid presses onto the gasket and compression settles at 30%. At 7 mm the tongue grips only 0.5 mm of lip and releases on a drop; at 11 mm the load angle goes oblique and whitens the plastic hook.

Closing runs centre-first on the assembly card, though only even load on both sides matters in service, which holds lip step difference under 0.3 mm. Force is re-checked after 5000 cycles against a 15% decay line; past that the catch insert is swapped and the lid stays untouched.

3. Hinge stop angle and pin fit along the full-length hinge

The hinge runs the full 180 mm rear edge, with a 4 mm stainless pin and 0.15 mm clearance. Its stop face meets at 105°, so the 0.9 kg lid neither falls back nor closes by itself when the case sits on a 15° slope. A stop under 95° crowds the opening; over 115° raises the bending moment at the root and cracks the pin bore over time.

Each bore sits inside a 2 mm reinforcement boss moulded with the shell and hinge seat in one shot. Pin insertion is held under 250 N; press harder and stress concentrates at the bore, showing as whitening after 5000 cycles. Hinge and latch are measured as two separate groups: radial pin clearance for the hinge, tongue-to-catch contact face for the latches, with neither reading standing in for the other.

4. Lip step re-check after a 1.2 m six-face drop

The case is dropped from 1.2 m onto all six faces with a 6.5 kg load, after 4 h at -10°C. Once the rig stops, the lip step comes first: close the lid and try a feeler gauge from 0.05 mm around the lip, reading eight points at the four corners and four edge midpoints, with a 0.4 mm maximum. A step out of tolerance means the lip ribs took permanent set, shifting the face where lid and gasket meet.

Industrial endoscope protective hard latch case moulding shop, rows of injection machines under a red crane beam, workers in red hard hats at tooling racks

The order is fixed: step, then force on both catches, then cracks. A good step with force under 270 N means new latches; a bad step with radial corner cracks retires the unit. Each case takes one drop round, since a second impact can hide the first set.

Re-check item	Gauge and value	Verdict
Lip step	Feeler from 0.05 mm	≤0.4 mm
Latch closing force	Pull gauge peak	≥270 N
Corner cracks	Visual plus 5× loupe	No radial cracks
Hinge pin clearance	Plug gauge	≤0.25 mm

5. Gasket compression and internal humidity after immersion

The gasket is EPDM, 8×6 mm section, seated in a 6.5 mm channel and compressed 30% at closure, from 6 mm to 4.2 mm. Below 25% the lip bubbles at 1 m depth; above 40% the gasket fights the 320 N latch force and tongue travel feels dead at the end.

Immersion runs 1 m deep for 30 min; the case is wiped, left 2 h, then opened with 10 g of desiccant inside. A gain of no more than 0.8 g means the seal holds. Temperature runs separately: 24 h at -20°C against a 12% set limit, then 24 h at 60°C against a 0.3 mm lip step.

Check	Condition and value	Verdict
Gasket compression	6 mm to 4.2 mm	25%–40%
Immersion	1 m depth, 30 min	Desiccant gain ≤0.8 g
Cold compression set	-20°C for 24 h	≤12%
Hot distortion	60°C for 24 h	Lip step ≤0.3 mm

Conclusion

The industrial endoscope protective hard latch case carries five coupled figures: a 150 mm cavity against a 300 mm coil envelope, 320 N per latch with 9 mm tongue travel, a 105° stop on a 180 mm hinge, a 0.4 mm lip step after a 1.2 m six-face drop, and 30% gasket compression paired with a 0.8 g desiccant gain. Each belongs to tooling, assembly, rig or immersion work, and none is converted into another. How a cable is coiled or pulled out inside the case is outside this discussion.

Industrial endoscope protective hard latch case

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