Quality Assurance & Inspection System

Quality Assurance | Incoming → In-process → Pre-shipment, three-stage control

検査を実施するTOHARUの工場

A three-stage control system: incoming inspection, in-process inspection and pre-shipment inspection. Storage-goods defects often surface after use, not on arrival. Beyond visual inspection of finished goods, we run lot-by-lot durability tests that reproduce real usage environments, preventing defects from being built in.

Basic Policy

Storage-goods defects often surface after weeks of use, not on arrival — hinge cracks on folding mechanisms, deformation in hot warehouses or cars, hinges becoming stiff. Such issues are hard to catch by visual inspection at shipping.

For this reason, beyond visual inspection we run durability tests reproducing expected usage environments on every lot. Our principle is to prevent defects from being built into the process, not to find them after shipment.

Inspection Flow

① Incoming

Material grade, thickness, strength and foreign matter checked lot by lot

② In-process

First-article check plus 2-hour sampling; dimensions, appearance and color difference measured

③ Pre-shipment

Sampling per JIS Z 9015-1; packaging and labeling verified

④ Release

Inspection report issued, lot number recorded, then shipped

Key Inspection Items & Standards

StageItemStandardMethod / Equipment
IncomingResin gradeMatches specified grade (PP/ABS/AS); no recycled material mixed inSample comparison, melt flow rate test
IncomingSheet thicknessSpecified thickness ±0.1mmMicrometer
IncomingFittings / hinge strengthTensile strength above specTensile tester
IncomingForeign matter / odorNone detectedVisual & sensory check
In-processDimensionsDrawing tolerance ±1.0mmCalipers, CMM
In-processAppearanceNo burrs, sink marks, color unevenness or scratches (limit-sample based)Visual vs. limit samples
In-processColor differenceΔE ≤ 1.5Spectrophotometer
In-processHinge cycle endurance10,000+ cycles (foldable models)In-house endurance tester
In-processWeightSpec value ±3%Electronic balance
Pre-shipmentLoad capacityStatic load 24h, no deformation or breakagePress test at 2× service load
Pre-shipmentDrop test80cm, 6 faces, packed condition, no abnormalityDrop tester
Pre-shipmentHeat / humidity60°C×24h and 40°C·95%RH×48h, no deformation or discolorationTemperature-humidity chamber
Pre-shipmentLabelingItem no., JAN code, origin, material and warnings legibleVisual, barcode reader
Pre-shipmentSampling inspectionPer JIS Z 9015-1, AQL 0 / 1.0 / 2.5Attribute sampling

* The above are representative items; inspection items and criteria vary by product specification. An inspection standard sheet is attached with each quotation.

④ Reliability Tests (per lot)

Load capacity, packed drop, heat/humidity chamber and hinge cycle tests are performed. Results are kept per lot and issued as PDF inspection or test reports on request (in Japanese).

⑤ Traceability

Every finished lot carries a lot number linked to raw-material lots, molding date, molds used, inspection records and shipment date, retained for 3 years. If an issue is reported, we can identify all units produced under the same conditions and report within a defined scope.

⑥ Environmental & Safety Compliance

Raw materials comply with the RoHS Directive and REACH Regulation. For food-contact products, testing based on Japan's Food Sanitation Law (MHLW Notification No. 370) is performed by external laboratories with reports issued. Recycling marks for plastic packaging are supported.

⑦ Quality Management System

A dedicated QC department reports directly to the representative. Weekly quality meetings review defect rates, claims and corrective actions, with minutes retained. Process control follows ISO 9001 principles.

Quality Warranty Terms

ItemDetails
Warranty period1 year from delivery date (under normal use conditions)
Initial defectsManufacturing-caused defects reported within 30 days of delivery are replaced in full, with round-trip shipping borne by us
Transport damageConfirmed by photos and compensated in the next shipment (cash refund available for first orders)
ShortageVerified against packing list and compensated in the next shipment
ExclusionsDamage from misuse beyond normal use, modification or natural disasters is excluded

Claim Handling Process

STEP 1 Intake

First response within 24 hours (in Japanese); photo, lot number and quantity requested

STEP 2 Root cause

Records cross-checked by lot number; investigation report within 5 business days

STEP 3 Corrective action

Recurrence-prevention measures in writing; full sorting and extra testing as needed

STEP 4 Horizontal deployment

Applied to other items sharing the same process/material, with results reported

STEP 5 Records

All records kept for 3 years for audits and review

Issuing Inspection Reports

Lot-based inspection reports are issued as PDFs in Japanese, covering items, spec values, measured values, judgment, inspection date and inspector. Submitted upon initial adoption and at periodic updates; format and copy count can be customized.

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