Restraint Locking

[Tmcdllr]

The mechanical (moving) locking/unlocking mechanism from my experience is typically called a "platen".

 

On Arrows there is traditionally one long single platen that is moved up and down by hydraulic arm/pump. On the underside of the train there is a vertical-oriented wheel attached to an arm that unlocks the restraints for that particular car. As the platen is raised the wheel moves along the metal surface. That motion in turn unlocks the restraint. You can most clearly see this on Arrow Suspended coasters.

 

As mentioned B&M's use the same basic idea except they have some electrical components to them. Hence the need for a battery to unlock seats when out of a station. On Arrows, however, its all mechanical, so all you have to do is step on the pedal to unlock a particular car....in fact some early Arrows only had pedals!

 

Actually, they are pneumaticlly (air) powered, by forcing compressed air into a cylinder it raises the platen and unlocks the restraint. That it why you hear a 'hissing' sound whenever they are locked/unlocked- it is the compressed air being forced in and out of the cylinder.

[Jumboshrmp]

I have a uestion. On B&M's what is the tube that goes along the back of the seat?

[CoasterFanatic]

^ If you are talking about the inverted model, the tube is there to drain the water that gathers over the riders (in a little dish looking thing). It guides the water under the seat where it can drain without covering you.

[twisted_propaganda]

On rides like Canyon Blaster at Adventuredome, I've noticed that the ride operators step on a small pad behind each car. I saw the same thing on Perilous Plunge at Knott's before they redesigned the trains.

[Hurricane]

That would be a small pedal on the back side of the car, the older arrow coasters use them (pointy cars mainly) and they have a wire that will trigger a emergency stop if the pedal lowers releasing the harness, The more recent arrow coasters still have these pedals, for the manual release of the harness in the event of a ride stop or evacuation, but otherwise they are automatic.

[niiicolaaah]

Wow, this is really complicated!

[Vallean]

There are various types of restraint locking systems. Very common are ratched-based ones. Better ones are typically redundant, which means that there are two separate wheels and two ratchets although they typically can lock the same axle (some have also an additional locking pin to limit the opening in case of total ratchet failure).

Hydraulic restraints work differently: Redundant hydraulically locked restraints feature two independant systems, each one comprising a double-action hydraulic cylinder, a check valve, a small hydraulic accumulator and a release valve. As double action cylinders have different active areas each side of the piston, a small hydraulic accumulator is required to compensate the volume different when a restraint is opened or closed. The check valve allows the retraint to be always moved in the closing direction but not opened unless being actively unlocked. The release (unlocking) of a hydraulic restraint is only possible if the release valve, which bypasses both cylinder chambers, is activated. On roller coasters, the release valve can be actuated mechanically or with a solenoid (electromagnet). There is no pump. The hydraulic accumulator is basically just like a small steel balloon made of two halves separated by an elastic membrane, one side is filled oil, the other side is precharged with gazeous nitrogen at a specified pressure (there are also other accumulator types). The hydraulic accumulator also compensates low oil leakages as well as oil volume variations due to temperature changes.

Modern rides have advanced restraint monitoring systems where basically various detectors and switches check if each restraint is correctly locked. All restraints have a fail-safe design, which means that there's no energy required to keep them locked.

Once a train has left the station there's normally no more monitoring possible as there's no wireless data link.

[phazan]

I always picture in my head a little gear type thing that spins as you move the restraint. Then there is a little notch thing that keeps the gear from spinning the other way. Pretty much like one of those tools (I forget what they are called) that will spin one way, but won't go the other way, that's used to tighten screws.

[chmilo24]

I used to work at PGA for about a month and I operated on 2 rides, Vortex and Grizzly. Since Vortex is a standing coaster, it used Hydraulics to lock the restaints. That is why the Ops have to warn you to get the restaints in the ideal position for yourself. Because once they lock it, its stuck there untill the end of the ride.

[cprocks22]

I found this a while ago but heres a really good article about how the hydraulic lab bars work on Intamin rides (TTD in particular), theres also some information on the launch system if your interested.

http://www.pointbuzz.com/ttdtech.htm