What is Osbourn?


Named after Osbourn Dorsey who invented the modern-day door handle and door stopper, the Osbourn range is designed to offer protection against unexpected start-up.


Compatible with a wide range of interlocks on sliding (IBL-S) or hinged (IBL-H) guards, as well as light curtains (PBL), Osbourn devices have integrated mounting plates for simple installation. With no need for wiring, our Osbourn solutions are designed to be easily installed on to systems that do not already provide a proactive inhibit function.


The devices in the Osbourn range come with personnel key(s), protecting operators who work inside the safeguarded space from being trapped and preventing the restart of the machine.

Fortress Osbourn interlock blocking and photo-electric blocking solutions for hinged door and light curtain applications

Main features of the Osbourn range


Interlock blocking devices work alongside existing interlocks or light curtains to add an additional level of protection and prevent unexpected start-up.


✅ Integrated mounting plates make installation simple and efficient

✅ Personnel keys as proactive inhibit functions

✅ Padlocks can be applied for additional personnel entering the area

✅ Stainless steel construction for use in a wide variety of environments

✅ Different orientations available to suit custom applications

Blocking Devices for Light Curtains


The rotation of a blocking plate interrupts the light curtain beam. PBL comes in multiple configurations to support installation on different branded light curtains.




Find out more

Blocking Devices for Guards


IBL devices are used to mechanically prevent the guard from closing, preventing the interlock safety contacts closing whilst operators are within the safeguarded space.​



Explore our product videos for more information about the Osbourn range

Interlock Blocking Device for Hinged Guards (IBL-H)


Interlock Blocking Device for Sliding Guards (IBL-S)


Photoelectric Blocking Device for Light Curtains (PBL)


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