Absolute encoder offers new options for controlling DC motors

An example of an innovative design philosophy applied to the control of DC motors with the emphasis on developing compact, flexible, energy-efficient products is being introduced by ROTALINK. Their Output Shaft Absolute Encoders provide accurate positional information to a resolution of +/- 0.35degrees with a performance which is unaffected by power loss and is self-correcting in the event of electrical interference.

These absolute encoders operate via contactless Hall effect technology which provides either a linear analogue output (0-5V) or reliable 10bit positional data sent via a SSI (Synchronous Serial Interface). However, when the digital option is chosen the benefits are longer life span, higher reliability and improved noise resistance.

The encoder is particularly effective when used in conjunction with Rotalink's 210 gearbox and 24mm brushed DC motor. The result is a compact and low-cost servo package measuring just 50mm × 50mm × 34mm, weighing 100g and offering important advantages over a hybrid stepper motor of equivalent size.

For example, at low speeds (<10rpm) it can achieve up to twice the torque whilst offering the same levels of accuracy (+/- 1degree). Whilst a stepper motor option will offer greater accuracy if micro-stepping is used, the downside is that it reduces torque to a fraction of its full step value. The high starting torque of the brushed DC motor makes the absolute encoder option particularly well suited to high-inertia loads. Also, closed loop positional feedback solves the problem of overshoot, or missed steps. Furthermore, if used with a high gear ratio long enough to provide less than 10rpm, the detent torque of a brushed DC motor is high enough to hold position. This can be achieved without the need for continuous power and therefore brings the added benefits of energy savings.

The absolute encoders are available as single turn and multi-turn options. The single turn option operates through the full 360 degrees of rotation to accurately monitor its position indefinitely and without power. The multi-turn unit operates to a maximum of 32000 revolutions whilst sill providing the full resolution of 10 bits per 360 degrees and is fitted with an integral rechargeable battery to provide full position monitoring for up to 100 hours when mains power is removed.

Using an extended SSI interface with the multi-turn unit allows the end-user the option of programming of zero position and maximum rotation limits as well as resetting any error codes.

Typical applications for these Absolute Encoder/Gearbox/Motor packages include motorised valves, pan/tilt mechanisms and vending carousels Further details are available from www.rotalink.com.

Rotalink Ltd

Cropmead
Crewkerne
TA18 7HQ
UNITED KINGDOM

+44 (0)1460 72000

www.rotalink.com

More from Rotalink Ltd

Rare earth motors offer more power in a compact package

Posted 3 years ago

Innovative gear motors help to make fresh coffee less of a grind

Posted 4 years ago

High-speed polymer gearboxes deliver material gains

Posted 4 years ago

Incremental encoder suitable for low-speed applications

Posted 4 years ago

Miniature power transmission range has space-saving options

Posted 6 years ago

Ovoid spur-planetary gearbox for swimming pool filtration valves

Posted 7 years ago

Rotalink motor gearboxes chosen for hairdressers' machine

Posted 7 years ago

New catalogue and site for miniature motors, power transmission

Posted 8 years ago

Three new high-performance models in spur ovoid gearbox range

Posted 8 years ago

AC synchronous geared motors supplied for peristaltic pumps

Posted 8 years ago

Customised gearboxes and actuators for OEMs

Posted 8 years ago

Low-cost speed-and-direction controller for DC motors

Posted 9 years ago

Heavy Case motors deliver smooth motion at a competitive cost

Posted 9 years ago

Miniature ovoid gearboxes in a choice of specifications

Posted 9 years ago

New catalogue: miniature power transmission systems and controls

Posted 10 years ago

Rare-earth brushed DC motors deliver twice as much power

Posted 10 years ago

New brushless Red Drive servo motor driver and controller

Posted 10 years ago

Ovoid style gearboxes now available with absolute encoder

Posted 10 years ago

Miniature brushless motors available with choice of options

Posted 10 years ago

Capabilities in miniature motors, transmission and control

Posted 11 years ago

3D CAD files for motors, gearboxes and transmissions

Posted 13 years ago

More products
19 hours ago
High-quality UK made ABS power supply cases
13A Plug-in and In-line styles from BCL Enclosures includes flame-retardant ABS models
1 day ago
Variohm Group buys Phoenix America
Based in Fort Wayne, Indiana ,Phoenix offers a range of absolute and incremental encoders, together with speed and proximity sensors, custom moulded magnets and more
1 day ago
New chain configurator aids machine builders
Tsubaki's recently unveiled configurator can make specifying chain a whole lot quicker and easier
1 day ago
Counterfeit bearings – NSK continues the fight against the fakes
The scale of the fake bearings problem has been highlighted with the discovery of around 23,000 counterfeit NSK packages and labels at a plant in Hebei Province, China
1 day ago
Parker launches new hydraulic fluid particle contamination monitor
The company’s icount LaserCM30 Particle Contamination Monitor is now available and can provide test results in 90 seconds
2 days ago
Last few places on Machinery Safety Course
Just a handful of places remain available on the last Pilz City & Guilds accredited Machinery Safety Course in 2020. Diary date is December 14th to 17th
2 days ago
Camozzi Automation launches new quick exhaust safety valves
Designed to provide a plug and play solution for OEMs that need to be compliant with Machinery Directive 2006/42/EC, Camozzi Automation says that its new quick exhaust 2-way safety valve range also complies with ISO 13849-1 covering the safe design of control systems which perform safety functions
2 days ago
SICK’s Open Service for IO-Link function blocks
A new open software service for control systems has been introduced by SICK
5 days ago
Automatic bearing lubrication brings ore inspiring results in mining
By installing automatic lubricators for bearings on its conveyor drive motors and belt pulleys, an opencast mine in Hungary has seen a range of benefits, including the prevention of unplanned downtime, longer bearing life and reduced repair work
5 days ago
Kinoulton company conveys COVID-combating masks
Here's a great example of the germ of an idea resulting in the combating of COVID