passenger rail doors that meet the U.S. Department of Transportation's Buy America requirements integrate a
flexible control system that provides light weight, a compact design and
programmable operation. Talgo, a leading
manufacturer and operator of innovative high speed passenger trains, will use
the doors in its new Intercity Series 8 train platform in the United
More than 14,000 unique internal
door systems designed and developed by Norgren have been installed in rail cars
worldwide since the solution was introduced in 1987. The system's light weight
design includes an integral controller that provides passenger detection and
anti-entrapment features. Its compact design fits into many applications with
limited space and is available in both electric and pneumatic versions. Long
service life and ease of maintenance help reduce the total cost of ownership.
"We have been supplying a number of
high speed rail customers this type of actuator for a number of years in
Germany," says Mark Densley, business development manager for Norgren Americas.
"We started out with a pneumatic version but the demand in the rail industry
has moved to electric doors."
electric system uses a
lightweight aluminum extrusion which is based on the company's pneumatic LINTRA
rodless-style cylinder. One advantage of the electric doors is that using programmable
operation, no regulators and valves need to be changed in the field. Once they
are set, electric doors are ready to go.
"We use the electric motor in conjunction
with a toothed belt which runs around the extrusion," says Densley. "In the
extrusion, there is a carriage attached to roller bearings with rubber wheels
on them. As the motor turns and the belt moves, it pulls the carriage which is
holding the door panel to the actuator."
One unique benefit of the product is
an integrated binary encoder that the controller is constantly monitoring as
the door is travelling. If there is a jam or someone standing in the doorway,
the controller will detect that to provide important obstacle detection and anti-entrapment
features that are very important in the rail industry.
All of the operation of the door
controls is programmable including the amount of time the door goes back into
the pocket and waits, and the amount of force acting on any obstacles. In
calculating the force, the system can use the current sent to the motor to
calculate the required force to be exerted on the door leaf.
The door control mechanism is fully
integrated with a standard footprint controller attached to the actuator.
Typically, the controller is matched with an I/O card which provides the
interface to the train's diagnostic system. If there is a jam or problem with
the belt, a signal communicates the problem back to the train management
system. The I/O card also
allows the system to use IR sensors on either side of
the doorway for detecting traffic and, if a person walks up to the door,
automatically opens as well.
"A key to the system is its compact
design," says Densley. "Many customers have space limitations in the area above
the doorway and obstacles such as HVAC piping and electrical wiring that get in
the way. To deal with those problems in the past in Europe is cut out areas in
the actuator to make it fit.
Because Norgren is supplying the door
actuator and controls as a custom system, it makes it easy to add specific
customer requirements and components such as locking mechanisms, detection
systems such as sensitive edges and latches to keep the door open, for example,
if there is a power failure.
Norgren transferred the technology
to the U.S. in 2010 to work on this project for Talgo. The U.S. market is slightly different because
of the forces involved to open the door and A.D.A. standards are slightly lower
than what is required in Europe. But by re-parameterizing the controller, those
adjustments can be achieved very easily.