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Umbrella metal part

Cantilever Crank Gearbox

Overview

Made by
Qinxi in-house
Materials
Zinc alloy housing (Zamak 3 / Zamak 5), Steel worm and gear set (supply chain), Steel crank handle (supply chain)
Finish options
Powder coat, Textured paint

Selection tips

  • The bore-to-worm-shaft fit sets both self-locking and noise; hold the bore within IT8.
  • Use a grease that stays soft in the cold: a stiff winter grease is why crank umbrellas become hard to turn in northern markets.
  • Rib the housing: a housing that spreads under load opens the gear clearance and the umbrella slips down.
  • Against a plastic gearbox: plastic is fine for light, short-life use, but commercial terraces need metal gears and a metal housing.

Manufacturing process & quality control points

Qinxi in-houseSupply chain / partnersIn-house or supply chain
  1. 1

    Product design & tooling

    Qinxi in-houseZinc & Aluminum Alloy Die Casting

    Qinxi designs and owns the housing die. A cantilever gearbox does more work than a centre-pole crank: it lifts the canopy and swings the arm, so the housing carries more load and the bore positions are set in-house.

    Quality control points

    • Centre distance of the bores · Engineering review of the tool plus CMM on first article · Each new tool or project
  2. 2

    Zinc alloy die casting

    Qinxi in-houseZinc & Aluminum Alloy Die Casting

    The housing is cast in-house; bore consistency is the watch point because the gear set is bought to a fixed centre distance.

    Quality control points

    • Bore diameter and centre distance · Plug gauge / CMM per drawing · First article + 1 pc per 2 h
    • Fill and porosity at bores · Visual under 600-1000 lx, 300 mm · First article + 1 pc per 2 h
  3. 3

    De-gating, deburring and polishing

    Qinxi in-houseZinc & Aluminum Alloy Die Casting

    Gates and flash are removed and the visible faces are polished in-house. This is part of the die-casting cell, not a separate finishing supplier.

    Quality control points

    • Residual burr and flash · Gloved touch check plus 10x loupe · Per lot, AQL 2.5 (ISO 2859-1 general level II)
  4. 4

    Plating or coating

    Supply chain / partners

    Coating is applied by the supply chain and checked for thickness and corrosion.

    Quality control points

    • Coating thickness · Thickness gauge per buyer spec · Per batch
  5. 5

    Gear fitting and lift test

    Supply chain / partners

    The gear set, crank shaft and handle are fitted and the lift is cycled under canopy load.

    Quality control points

    • Lift and swing under load · Cycle the crank with the canopy fitted, no slip, no binding · 100%
    • Crank effort · Push-pull or torque gauge to agreed limit · 5 pcs per batch

Used in

Cantilever / Roman Umbrella

Relevant compliance

Get a quote for Cantilever Crank Gearbox

Custom materials, finishes and logos available. Send your drawing or sample.

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