Optical Encoder
QR12 Optical Encoder Design Features:
1. Low profile assembled height
2. Bearing design simplifies encoder attachment
3. Resolutions up to 20,000 lines per revolution
4. 4, 6 or 8 pole commutation
5. Multiple Bolt Circle mounting
6. Through shaft sizes up to 0.375” (10mm) Diameter
7. High Noise Immunity
8. Cost Competitive with Modular Encoders
9. 500 kHz Frequency Response
10. RoHS Construction
Quantum Devices, Inc. Model QR12 provides an improved feedback solution in applications typically using
modular encoders. With an over all height of less than one inch and the stability of a bearing encoder design,
the model QR12 can provide significant performance upgrades in applications limited by traditional modular
encoder solutions. Outputs consist of a quadrature with index pulse and three-phase commutation. A flexible
member allows for much greater tail shaft run out and TIR than can be tolerated by modular encoder designs,
plus it provides 30 degrees of rotation for commutation timing.
SIZE 15 RESOLVER MOUNTS
Utilize the optional resolver mount adapters to mate the QR12 – 1.280” Flex mount option to Size 15 Pancake
Resolver motor configurations. Eliminate the expensive mounting servo clamps by attaching either the two or
three point adapters directly to the servo clamp holes. Assemble the QR12 to the adapter plate using (2) 4-40
screws. For jam nut attachment to threaded motor shafts, refer to JR12 Jam Nut Mount Optical Encoder
Literature.
ENCODER INSTALLTION INSTRUCTIONS
1. Using two fingers slide the encoder onto shaft.
2. For additional security, Loctite can be applied to the encoder hub set screws. Remove the encoder’s set
screws and using tip of toothpick apply appropriate amount of Loctite thread locking adhesive. A non-
permanent adhesive is recommended.
3. Insert and tighten encoder set screws using a .050” hex wrench. Typical torque range of 50 to 80 oz-in.
4. Fixture the stainless steel flex mount to the mounting surface with #6-32 button head screws.
For brushless motors requiring commutation timing:
· Encoder drawings indicate position of encoder hub to encoder body at Z (index). Rotating the hub to this
position allows for known U channel transition state (prior to step one above).
· Powering appropriate motor windings allow for locking motor shaft location to match the appropriate U
transition (prior to step one above).
· While mechanically back driving the motor, monitor motor winding EMF position to the powered encoder
position. Rotate the encoder stainless steel flex mount to achieve accurate timing of encoder commutation
feedback channels to the appropriate motor winding EMF. Tighten the screws retaining the encoder
stainless steel flex mounts.
