Term
What is the module equation? |
|
Definition
| d = mN, where d is pitch diameter, m is module, N is number of teeth |
|
|
Term
| What is the gear ratio equation? |
|
Definition
| m_G = (Ngear/Npinion) = (Tgear/Tpinion) = (w_pinion/w_gear) = (d_gear/d_pinion) |
|
|
Term
| What is the definition of pressure angle? |
|
Definition
| Angle between horizontal and tangent to both tooth curves OR angle between pressure line and tangent to both pitch circles |
|
|
Term
| What is the procedure to determine Ngear and Npinion without interference? |
|
Definition
1. Determine desired gear ratio (m_G)
2. Select pressure angle and tooth type (full depth vs. stub)
3. Use Npinion equation to find the MINIMUM
4. Use the gear ratio to determine Ngear and check that Ngear is less than the MAXIMUM value given by the Ngear equation
6. Select module m to determine pitch diameters |
|
|
Term
| How do you find the tangential and radial forces transmitted to the pinion and gear? |
|
Definition
F_t_gear = F_t_pinion = (T_g/r_g) = (T_p/r_p)
F_r_gear = F_r_pinion = (F_t)tan(phi)
where phi is pressure angle
|
|
|
Term
| What are the stress and strain definitions in 1D? |
|
Definition
stress = (force/area)
strain = (change in length/original length) |
|
|
Term
What are the stress and strain definitions in 2D?
What is the stress-strain relationship in 2D? |
|
Definition
Normal stress: Force acting normal to area/area
Shear stress: Force tangential to area/area
Normal Strain: Change in length/original length
Shear strain: Total change in a right angle
Normal stress in x = E*(Normal strain in x)
(Normal strain in y)*E = -v*(Normal stress in x)
where v is Poissons ratio |
|
|
Term
| What are the stress-strain relationships in 3D? |
|
Definition
|
|
Term
| What are the strain definitions in 3D? |
|
Definition
|
|
Term
| What are the equilibrium equations in 3D? |
|
Definition
|
|
Term
| What are the definitions of base units and derived units? |
|
Definition
Base units: Three units that are explicitly chosen
Derived units: Unit that is defined in terms of base units
[image] |
|
|
Term
| What are the key differences between stress and strength? |
|
Definition
Stress: A state property at a specific point in a body
Strength: An inherent property of a material (can be dependent on other factors) |
|
|
Term
| How do principal stresses change when the coordinate system is rotated by an angle theta? |
|
Definition
They don't. Principal stresses are invariant under a coordinate transformation.
[image] |
|
|
Term
| What are the major differences between ductile and brittle material? |
|
Definition
|
|
Term
| What are the Von Mises stress equations? |
|
Definition
|
|
Term
| What is the max shear stress theory and when does it predict failure? (Hint: Stress intensity) |
|
Definition
|
|
Term
| Compare and contrast MSS and DE theories. |
|
Definition
|
|
Term
| Summarize the various failure theories for ductile and brittle material in chart form. |
|
Definition
|
|
Term
| What are the 3 stages of fatigue development? |
|
Definition
|
|
Term
What is the procedure to find Kf for a given geometry?
|
|
Definition
1. Find Kt for the given geometry
2. Find q for the material and notch radius
3. Kf = 1+q(Kt-1)
OR
2. Find neuber constant (sqrt(a)) using equation
NOTE: only for reversed bending or axial, Sut must be in kpsi and sqrt(a), sqrt(r) in sqrt(in.)
(690MPa = 100 kpsi)
3. Kf = 1+(Kt-1)/(1+sqrt(a/r)) |
|
|
Term
| What is the relationship between load intensity, shear force, and bending moment? |
|
Definition
q = dV/dx = (d^2)M/dx^2
where q = externally applied load intensity
V = internal shear force
M = internal bending moment |
|
|
Term
| What are the relationships between V (internal shear force), M (internal bending moment), shear stress and bending stress? |
|
Definition
|
|
Term
| How do you calculate the shear stress due to an internal torque? |
|
Definition
|
|
Term
| Compare externally applied axial force, cencentrated moment, concentrated force, distributed load, and pure torque in terms of the internal loads and stresses they cause. Also show a stress distribution at the cross section and equation for each external load. |
|
Definition
|
|
Term
| Explain how a constant bending moment can cause cyclical completely reversed bending on a rotating shaft. |
|
Definition
|
|
Term
| For a constant 2D external bending moment applied to a rotating shaft, determine Ma and Mm at a given critical point. Assume Mxy and Mxz represent the magnitude of the bending moment in the XY and XZ planes respectively. |
|
Definition
|
|
Term
| What are the characteristics of a deep groove ball bearing? |
|
Definition
|
|
Term
| What are the characteristics of a double row deep groove ball bearing? |
|
Definition
|
|
Term
| What are the characteristics of an angular contact ball bearing? |
|
Definition
|
|
Term
| What are the characteristics of cylindrical roller bearings? |
|
Definition
|
|
Term
| What are the characteristics of tapered roller bearings? |
|
Definition
|
|
Term
| What are the characteristics of double row tapered roller bearings? |
|
Definition
|
|
Term
| What are the characteristics of thrust tapered roller bearings? |
|
Definition
|
|
Term
| What are the rules for good design practice when arranging bearings? |
|
Definition
|
|
Term
| What is the definition of bearing rating life? |
|
Definition
1. Number of revolutions at which 10% of a random sample of bearings are expected to fail.
2. Hours of operation at constant speed that 90% of a sample can be expected to reach without failure. |
|
|
Term
| What is the relationship between applied radial bearing load F and bearing life L? |
|
Definition
|
|
Term
| What is the procedure for determining the life of a bearing subjected to axial thrust and radial loading? |
|
Definition
|
|
