Cantilever Sliding gate design 2

[davincigee]

Hello guys,
I need your urgent help with this. I need to design a cantilever sliding mechanism for a gate weighing 1000kg moving across a distance of 15m for both opening and closing sequence. Will be grateful if i get some literature or a sample design to guide me to selecting the individual components including the sizing of the motor-gear component that will drive the rack and pinion.

Thanks in advance.

 

[kiwitom235]

what are the problems you are having with designing it?

 

[Jboggs]

Go look at a powered fence gate at a local facility. How do you already know its weight? I would suggest using a roller chain drive rather than rack and pinion. It will be cheaper, simpler, and easier to maintain.

 

[davincigee]

Thanks kiwitom235 and Jboggs. Well to be very frank with you, this is my very first time of attempting this. I need to put these on paper. Was hoping that I could get a sample design to sort of guide me on how to go about it. I know the mass(sorry not weight) of the gate because I did a rough estimate by adding up all the individual components that were welded together. For instance, 50mmx50mm hollow square bar of thickness 3.0mm has a standard mass of 4.39kg/metre, and so on and so forth. Hence my estimation of 1000kg.

Jboggs, if you can help out with the roller chain drive mechanism for a sliding gate, that will ne much appreciated. Thanks

 

[Jboggs]

Drive around your area looking for businesses surrounded by chain link fence. Many of them will have sliding gates instead of swinging gates. Study how they are driven. You will probably see a long chain anchored between the vertical posts at each end of the moving gate. Somewhere along the length of the chain you will see a stationary drive device. Inside that device there are two idler sprocket and one drive sprocket. The chain comes into the drive below one of the idlers, loops up to the drive sprocket, wraps 180 degrees around the drive sprocket, comes down to the second idler, and then exits horizontally. When the drive sprocket rotates the gate moves. You can also search online for fence and gate equipment manufacturers.

 

[Nescius]

Who built the gate? They may be a good resource. I hope they didn't build a 1000kg gate, 15m long, cantilevered out in space, without any regard to how it would be mounted and moved. That's a pretty big gate and it would probably be easy to ruin if it weren't supported in the way the designers accounted for.

 

[MintJulep]

The opening is 15 m?

How long is the gate itself?

 

[MikeHalloran]

A truly cantilevered gate would be unusual, and probably expensive.
Typical sliding gates have a pair of ~300m rubber tired wheels at the distal end,
and a stationary roller at the proximal end,
or some sort of rail/roller guiding the proximal end,
and a roller chain drive, as noted.

1000kg is damn heavy, unless there is some vehicle attack/impact resistance requirement.



Mike Halloran
Pembroke Pines, FL, USA

 

[MintJulep]

How long do you want it to take to open and close?

1000 kg is non-trivial. You'll need to think about acceleration and deceleration.

Slamming it against end stops is probably sub-optimal and likely dangerous.

 

[davincigee]

Yes. The gate in my estimation is 1000kg. Reason? It serves as a barricade for access into an industrial parking lot for heavy duty trucks; articulators, bulk receipt vehicles, etc. The reason I chose a cantilever design is because it is pretty simpler and requires less maintenance, unless I am wrong and I am open to other suggestions on other cost effective methods. So I managed to size the requirement for a motor to be able to operate this massive object across a 15m length opening and I obtained a motor size of 3hp.

F(Force to overcome) = (Torque of motor) x ((Gear ratio)/(radius of pinion))

Any assistance on a sample design on any cantilevered sliding gate will be deeply appreciated. Thanks

 

[davincigee]

MintJulep, well I require that the speed of the opening and closing doesn't exceed 0.2m/s. The idea is to slowly open the gate in the morning and keep it open till close of business.

 

[davincigee]

And another point to note is, there will be an actuator to control the limits of closing and opening. I don't want to focus on the automation aspect now. Just the civil and mechanical aspects as well as the motor.

Thanks fellas

 

[SnTMan]

Ref:

http://www.americasfencestore.com/pages/Chain-Link-Sliding-Gates.html

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[davincigee]

Thanks SnTMan.

Much appreciated