precision step unit
Precision Step Units Type SRA
Precision Step Units Type SRA are the mechanical components of the Precision Step System. Mounted between the drive motor and indexed output, the SRA Unit will stop and start this output quickly and precisely.

The two fast-working solenoid valves in the step unit are activated by the system electronics. When the solenoid valves are activated, vacuum is generated in the channels leading to the clutch and brake side, respectively. This vacuum sucks the clutch/brake disc against a friction ring and starts/stops the shaft.

The step unit is supplied with vacuum from a vacuum pump or central vacuum source. The vacuum operating pressure required for all SRA units is 0.7 bar.


Combine the fast-acting SRA step unit with controls from the flexible SRB range of electronics - and obtain a positioning system which is:-

• Reliable -
A true system approach matching the SRA step unit with one of the specifically engineered electronic controls ensures great precision at high speeds.

Short response time makes it possible to achieve high repeat accuracy at the highest speeds.

The principle of design guarantees a long operating life.

Renovation service means little or no down-time.

Protection against electrical noise prevents unintentional start and stop signals.

• Maintenance-free -
The design principle eliminates the need for maintenance and adjustment.

• Designed for the future -
Flexible and versatile electronic controls make it possible to offer solutions to customer specific applications.

Extensive application know-how guarantees optimum system design.

• Economical -
High cycling frequency allows for considerable increase in productivity.

High repeat accuracy means savings in materials.

Fast and easy installation of the product reduces expensive interruptions and keeps down-time to a minimum.

Maintenance-free operation leaves more time for other jobs.