Need to source a vehicle operated switch, could be similar to garage hose rings bell?

I have been asked to solve a problem.
It seems that our heavy equipment operators do not like to get off the loader when they need to operate the hydraulic screen dumper on the hopper that they feed. I considered remote control units but I want to limit the range to within sight in case some poor bystander gets in the way when the operator leans on the remote from the other side of the plant.
It occured to me that the air hose you used to see at the garage that would ring a bell would be a possible model. Larger hose, to pressure switch contacts in parallel to pushbutton.
Anyone have experience with this type of input device. Other approaches to the problem welcome.
Must be compatible with +40 to -40 degrees C, snow, mud, big loader...

thanks,

Brian.

Why not a buried inductive loop actuator?

One brand.

Another (PDF)

Sorry, but I don't have any vendor suggestions, but I foresee problems with the pressure switch idea. Presumably, the hose is on the floor and the loader drives over it as it approaches the hopper. What happens if the loader operator spills some of the load onto the floor instead of getting it into the hopper? I expect that normally the loader operator would scoop up what he spilled and dump it into the hopper. With a hose on the floor, won't he also scoop that up?

How about a photoelectric sensor located near the hopper and a laser pointer in the cab of the loader?

Sliver.

I second the inductive loop. The truck drivers will quickly destroy any device that needs physical contact and a loop in the floor is the closest thing to indestructable I have found.

Andybr

It seems to me that what you really want to detect is not merely that there is a vehicle present, but that a bucket is being dumped or is about to be dumped. A high mounted photo switch (or swtiches) set in an appropriate location to detect a loader bucket being rasied in the hopper feed area might be the way to go.

To explain better,

The loader feeds a hopper that has a screen/grizzly to prevent oversized material from entering the hopper. To clear the oversized material the screen can be lifted hydraulically to dump the material on the ground infront of the hopper where the loader can scoop it up and deposit it elswhere.
I just did a driveby of the area and it occurs to me that the rubber hose idea is not the best as well. Lazer pointer to photo eye. Interesting. The system has a hydraulic pump that must be started manually. Two pushbuttons, one for raise and one for lower.
It looks like I need 3 seperate operations. The operator can get his arse off the loader to start the pump. I can put it on a timer to automatically shut off. Then perhaps an inductive prox switch mounted below the near lip of the hopper where the operator can position his bucket to raise the screen, dumping the material directly into the bucket. Might work!
Now how to activate the lowering function. HMM...
Perhaps good place for the inductive loop.
Back away until loop is covered, wait until screen is in place, drive away.

Whatcha think?

Brian.

We have some pretty ingenious operators at our plant. Since we had too much damage with them driving up to panels on the forklift and accidently hitting the panel/HMI, we installed bollards in front of the panels to make sure they would get off the forklift and operate the unit. I'm sure some of you can image what happens next.....


One operator took a broom stick (minus the bristle parts) and now (or I should say he used to) use that as an extension of his arm to operate buttons. Had to threaten them all with their jobs to make them stop.

I know this is of no help in you original question but I hope that you evaluate whatever you do for more than just keeping an operator from getting off the loader. The safety implications are great if things operate with just something moving close to it or driving near it. A risk assessment of this system I would think is a must. Having things start just because you are near it is a little scary. You must make sure that the equipment starting for the right reason.

Sliver said:

The system has a hydraulic pump that must be started manually. Two pushbuttons, one for raise and one for lower.
It looks like I need 3 seperate operations. The operator can get his arse off the loader to start the pump. I can put it on a timer to automatically shut off. Then perhaps an inductive prox switch mounted below the near lip of the hopper where the operator can position his bucket to raise the screen, dumping the material directly into the bucket. Might work!
Now how to activate the lowering function. HMM...
Perhaps good place for the inductive loop.
Back away until loop is covered, wait until screen is in place, drive away.

Whatcha think?

Click to expand...

I think you make it too complicated. If you can turn off the pump automatically with a timer why can't you turn it on when the operator turns on the infra red to raise the screen? Then when the infra red is not on lower the unit. After an appropriate time turn off the pump. All on one input

milldrone said:

I think you make it too complicated. If you can turn off the pump automatically with a timer why can't you turn it on when the operator turns on the infra red to raise the screen? Then when the infra red is not on lower the unit. After an appropriate time turn off the pump. All on one input

Click to expand...

Yeh I was coming around to that solution as well. I still like the operator getting off the loader to start the pump, take a look around, make sure no-one is having a smoke break under the hopper. Plus the hopper will not activate accidently because the operator must make an active desicion to start the pump.
Take away the current manual raise - off - manual lower control and replace with manual raise - pause - auto lower. The e-stop on the pump should be a good safety stop in case auto lowering needs to be halted. I would need a new prox\limitsw on the closed position to stop closing. Saves the cost of the inductive loop.


Just might fly,

Brian.

Sliver,

I did find some imbedable in pavement vehicle sensors from banner
http://www.bannerengineering.com/products/category.php?cat_id=44