Robot Rotary Index Table Housing 7075-T6 Aluminum Hirth Coupling Seat 5 Arcsec

Why Indexing Accuracy Starts in the Housing

An index table is judged by one number: how far the table is from where it should be. That number is fixed by the housing long before the motor or encoder is fitted. The bearing bore sets the axis, the table face sets the reference plane, and the Hirth coupling seat sets every angular position after that. If the three do not share a datum, no amount of servo tuning removes the error.

This housing is machined so all three do share a datum: bore, table face and coupling seat are finished in one clamping, then the coupling ring is cold-fitted into the seat and ground in place. The teeth are cut and matched by lapping the pair, so contact across the tooth flanks is even rather than concentrated on one side.

How the Housing Is Built

The route exists to protect the datum chain. Every step after stage 04 is done without re-establishing the axis from a fixture.

Precision Capability

Custom Rotary Housings

Housings are made to your drawing, including the coupling arrangement and the drive interface.

• Outer diameter 100-600 mm, bore 30-300 mm, height 40-250 mm
• Materials: 7075-T6, 6061-T6, 6082-T6, 2024-T351, 4140 pre-hardened steel, ductile iron on request
• Coupling options: Hirth ring, curvic coupling, face-tooth ring, dowel-pin indexing, plain lapped face
• Drive interfaces: worm wheel seat, RV reducer seat, harmonic drive flange, direct-drive rotor mount
• Features: T-slot grid, centre bore, cable window, coolant channel, encoder bracket, brake mount, lifting holes
• Hardened inserts: 4140, 17-4PH or bearing steel rings, cold fitted and ground in place
• Input formats: STEP, IGES, X_T, STL, DXF, 2D drawing with GD&T, or a sample for scanning and rebuild

Confidentiality

The Factory

Dongguan Changxinda Precision Technology Co., Ltd has made custom parts since 2008. Equipment covers 4-axis and 5-axis machining centres, turn-mill combination lathes, CNC lathes and milling machines, plus surface grinding and lapping, backed by an ISO 9001:2015 quality system and an in-house CMM room. Over 200 customers in medical equipment, robotics, automotive, aerospace, automation, laser, LED, lithium battery and precision instruments are supplied from this plant, and 50-60% of output is exported. Ring fitting, in-place grinding and tooth lapping are done under this roof.

Delivery

• Capacity around 10,000 pieces per month for this housing family
• Repeat orders keep the same lapping plate and ring source, so a spare housing indexes the same as the original
• Each part number allocated across two machining centres to protect your date
• Express, air and sea freight; EXW, FOB or CIF terms; ground faces protected with film and hard covers
• Rush capacity for line-down situations, quoted with a date we can meet

Key Features

• 7075-T6 housing for stiffness under clamp force
• Bore, table face and coupling seat finished in one clamping
• Hardened 4140 Hirth ring, cold fitted and ground in place
• Teeth lapped against the mating ring, blue checked to 80% contact
• Indexing verified at ±5 arcsec, record shipped per unit
• Table face flat to 0.005 mm, ground not milled
• 5-axis lugs, windows and pockets without disturbing the axis
• NDA-protected handling and project-code documentation

Typical Applications

• Robot rotary joint and wrist rotation housings
• CNC machine tool indexing tables and rotary stages
• Semiconductor wafer handling rotary stages
• Automated machinery rotation platforms
• Pick-and-place turntable components
• Medical and laboratory rotary positioners
• Inspection and metrology rotary tables
• Test rigs and endurance benches

FAQ

Q: Is the Hirth ring part of the housing or a separate item?
A: It is cold fitted into the housing and ground in place, so the ring and the housing behave as one part. That is how runout and indexing stay attached to the housing instead of drifting with an insert.

Q: Can you reach finer than 5 arcsec?
A: Finer is possible with more teeth, harder rings and a different clamp arrangement. We review tooth count and clamp design before quoting, and we do not accept a specification the assembly cannot repeat.

Q: Will you sign an NDA before we send the table drawing?
A: A mutual NDA is signed first, covering drawings, models, scans and samples, including indexing specification and drive interface.

Q: Do you grind the table face or mill it?
A: Ground, after the coupling ring is seated and the housing has been allowed to settle. Milled faces do not hold 0.005 mm across a table diameter in service.

Q: What is the minimum order?
A: One unit, with no tooling charge and no programming fee, so a single housing for a prototype table is a normal order.

Q: Can the housing take a worm wheel or an RV reducer?
A: Yes. Worm wheel seats, RV reducer seats, harmonic drive flanges and direct-drive rotor mounts are all machined from your drawing, with the seat ground concentric to the bearing bore.

Q: What do you need to quote?
A: 2D drawing with tolerances, 3D model, tooth count and indexing requirement, drive interface, quantity and target date. Quote and DFM comments return within 24 hours.

Related Parts From The Same Plant

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• Robot Base Plate MIC-6 Cast Aluminum Double-Sided Machined 0.01mm Flatness Dowel Datum