Encoders                                                                     

RGH22 series
Integral interpolation in a robust package

The RGH22 series offer a full range of features suitable for use in a wide range of motion systems, offering high resolution and high speed with stability and reliability.

RGH22/26/41 applicators
Scale applicator devices for RGH22/26/41 readheads

End clamp options
Fixing mechanisms for flexible scale

Reference mark options
Magnetic actuator device used to find home position

Limit switch options
Magnetic actuator device used for limit detection

RGS20-S - 20µm tape scale
20µm pitch flexible tape scale

RGH22 readheads
Digital and analogue output readheads

RGH22/26/41 applicators
Scale applicator devices for RGH22/26/41 readheads

Scale installation is made quick and easy using dedicated application tooling, which ensures the scale is positioned accurately along the entire axis length. The release paper is manually or automatically removed as the scale is installed using the movement of the machine axis.

Using a simple jig, the readhead, reference mark and limit switch actuators are correctly located relative to the scale. The readhead set-up LED indicates when optimum alignment is achieved; all that remains is the installation of the adhesive end clamps.

• Easy scale installation - Applicator tool enables rapid scale installation Unique applicator devices - enables quick and easy installation No need for drilling or tapping
• Parallelism of scale with respect to the axis guaranteed every time

End clamp options
Fixing mechanisms for flexible scale

There are two methods used for mastering tape scale to substrates;

• Adhesive end clamps use a specially formulated 2-part epoxy to fix the clamps at each end of the axis to ensure that the scale matches the thermal behaviour of the substrate
• Where adhesive end clamps are inappropriate, mechanical bolt-down end clamps are also available

Reference mark options
Magnetic actuator device used to find home position

Reference mark outputs are optional on all readhead models to provide a repeatable home or zero position. Compact magnetic actuators are positioned at one or more user-defined locations adjacent to the scale, which the readhead senses when passing.

There are two types of reference mark :

• Standard reference mark : magnetic reference mark actuators - reference pulse triggering device for mounting on the substrate adjacent to the scale
• 90° mount reference mark : magnetic reference mark actuators, mounted vertically for use with RGH24/25 readheads
  Actuators are premounted on a convenient bracket for easy installation

Limit switch options
Magnetic actuator device used for limit detection

Limit switch outputs are available as an option on all readhead models and on certain models, dual outputs are also available. As an end of travel indicator, compact magnetic actuators are positioned at the end of each axis adjacent to the scale, which the readhead senses when passing.

Limit switch options :

• Limit switch actuators - mounted horizontally adjacent to the scale, trigger the sensor inside the readhead when the readhead passes over the actuator
• 90° mount limit switches - vertically mounted limit switch actuators for use with RGH24/25 readheads

RGS20-S - 20µm tape scale
20µm pitch flexible tape scale

The scale used by all RG2 readheads is made from a thin flexible steel strip, which is gold plated to give high reflectivity and corrosion resistance. A tough lacquer coating provides handling resistance and allows easy cleaning.

It is attached by means of an adhesive backing tape to most engineering materials, including metals, ceramics and composites. Long continuous scale can be supplied on a reel and cut to length at the point of installation ensuring minimum waste and efficient inventory management. Features include :

• Easy scale installation - applicator tool enables rapid scale installation Ordering flexibility - cut to suit scale and common scale for each range Available on a reel - scale can be cut to suit any axis length Lengths up to 70m - compatible with even the largest machines
• RGS-S scale is designed to match the thermal behaviour of the substrates is affixed to, simplifying thermal compensation

RGH22 readheads
Digital and analogue output readheadsThe RGH22 readhead offers an extensive list of features with integral interpolation in a robust package. Using Renishaw's unique flexible 20µm RGS-S tape scale, it is suitable for use in a broad range of applications, and can output resolutions as high as 50nm. Key benefits and features include:

• Non-contact format enables high speed operation without wear Easy readhead installation using set-up LED and setting shim (gauge) Reliable operation - solid state technology ensures long term reliability Lissajous (signal) stability minimises cyclic errors Excellent metrology - high accuracy, linearity and repeatability Dual Limits - determine the end positions of the axis Broad compatibility - variety of output configurations are available as standard
• Multiple connector variants for easy integration

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