How does the BX25 park brake work?

[OffGridiot]

Hey all,
Today I was installing the grapple on the front end of my BX25 (more about that later) and I discovered something that surprised me about the park brake.
I had the rear of the machine off the ground, blocked up with one wheel removed and the other just barely clearing the ground. I had the park brake set. I nudged the hub by accident while working on a hydraulic line, and it moved (spun). I grabbed the hub and spun it some more and noticed the wheel on the other side spinning (in the opposite direction...which I know is normal with differential axles). I re-checked that the park brake was set....it was. Once I was finished the job, (and after I calmed down from the excitement of having a new grapple to play with) I tested the park brake, and it was working perfectly fine.
So....
Why would those wheels have been able to spin while suspended if the park brake was set?
When I apply the brake pedal, what/where/how is the braking force being applied in the drivetrain? In the front wheels?
Just curious.
Thanks in advance

Bruce

 

[woodskiff]

Wet disc system....travelling brake and the parking (which just locks the brake pedal) is incorporated in the transmission. Hope this helps

 

[Grouse Feathers]

Since the brake only locks the transmission remember to block the wheels or put it in 4 wheel drive whenever you are working on a BX tractor with a rear wheel off the ground.

Larry

 

[OffGridiot]

Thanks for the replies, guys.
It never hurts to remind people about safety issues, Larry. I've been guilty in the past of cutting a few safety corners but crawling under heavy things is not something do in a casual manner. I'm a fan of plenty of solid wood blocking.

So if the brake is only being applied to the transmission, is that sort of like putting your automatic car in 'park' and not setting the e-brake? That doesn't quite sit right with me because of the fact that you can't feather the 'park' in your car to slow down on a hill....
I'm somewhat familiar with wet disc pack setups in larger equipment (I work in an open pit mine) but the ones I've seen are set up at the wheels. I can see where it could make sense to locate the brake discs somewhere other than the wheels but the effect still needs to be the same....stop the wheels from rotating.
If the wheels in that situation were able rotate in opposite directions, is it possible that the braking system allows only that? And to try to rotate them in the same direction wouldn't be possible?
I'm gonna have to (with the help of my wife, I guess) conduct that experiment tomorrow. Lift all 4 wheels off the ground and see which combination of wheels we can spin in which directions, with the park brake applied.

Still scratching my head...

Bruce

 

[Grouse Feathers]

With all 4 wheels off the ground and the parking brake set:
In 2 wheel drive both front wheels should turn freely any direction and the rear wheels will turn in opposite directions.
In 4 wheel drive the front wheels will turn in opposite directions, the rear wheels will turn in opposite directions and the front and rear wheels will be independent of each other when turned.
With the BX parking brake locked it is like park in a car, the difference is park in a car is a mechanical lock that can't be slipped like the brake in a BX.

Larry