marcusvonbrutus
Marine/Ocean
I am designing a manually adjustable master cylinder that will adjust the amount of spring compression "preload" for a coil-over-damper setup for our product. This is done by pushing hydraulic fluid from the master cylinder through a hydraulic hose to a hydraulic "ram". The ram will extend or contract through a range to acquire the desired preload.
The range of preload force required is between 90lbs - 300lbs.
Where I need a little help is determining how to calculate the torque at the knob when compressing the spring at predetermined locations.
knowns:
1. force @ ram = force @ cylinder (let's make it 350 lbs)
2. pressure at each component is determined by the area of each component.
3. thread pitch = 1/2"-10 (ACME)
4. radius of knob = 1.5"
5. coefficient of friction (stainless on stainless ACME)= 0.16
I am struggling on how to incorporate the mechanical advantage from the thread pitch into the calculations. I understand that a coarser pitch = harder / finer pitch = easier action at the knob.
My desire is to tweak design parameters to get a reasonable action at the handle.
The range of preload force required is between 90lbs - 300lbs.
Where I need a little help is determining how to calculate the torque at the knob when compressing the spring at predetermined locations.
knowns:
1. force @ ram = force @ cylinder (let's make it 350 lbs)
2. pressure at each component is determined by the area of each component.
3. thread pitch = 1/2"-10 (ACME)
4. radius of knob = 1.5"
5. coefficient of friction (stainless on stainless ACME)= 0.16
I am struggling on how to incorporate the mechanical advantage from the thread pitch into the calculations. I understand that a coarser pitch = harder / finer pitch = easier action at the knob.
My desire is to tweak design parameters to get a reasonable action at the handle.
