KINEMATICS

Question 1

WHat is the mobility equation?

Answer 1

m=3(n-1)-2j₁-j₂

Question 2

What is grashoff’s law?

Answer 2

s+l<=p+q

Question 3

What condition makes a crank rocker?

Answer 3

’s’ is next to base

Question 4

what condition makes a rocker-rocker?

Answer 4

’s’ is opposite to the base

Question 5

what condition makes a drag link?

Answer 5

’s’ is base

Question 6

what is a change point mechanism?

Answer 6

when s+l=p+q

Question 7

How can you have a triple rocker?

Answer 7

s+l>p+q

Question 8

WHat is the harmonic equation for rise and return?

Answer 8

• Rise:
  
  • y₁=L/2(1-cos(πø/ø₁))
• Return:
  
  • y₃=L/2(1-cos(π(ø-ø₃₎/(ø₂-ø₃)))

Question 9

WHat is the cycloidal equation for rise and return?

Answer 9

• Rise:
  
  • y₁=L[ø/ø₁-(1/2π)(sin(2π(ø/ø₁)))]
• Return:
  
  • y₃=L[(ø-ø₃)/(ø₂-ø₂)-(1/2π)(sin(2π((ø-ø₃)/(ø₂-ø₃))))]

Question 10

What is the cubic equation for rise and return?

Answer 10

• Rise:
  
  • y₁=L[3(ø/ø₁)²-2(ø/ø₁)³]
• Return:
  
  • y₃=L[3((ø-ø₃)/(ø₂-ø₃))²-2((ø-ø₃)/(ø₂-ø₃))³]

Question 11

Harmonic Max?

Answer 11

y’=Lπ/2ø₁

Question 12

Cycloidal Max?

Answer 12

y’=2L/ø₁

Question 13

Uniform Max?

Answer 13

y’=L/ø₁

Question 14

Cubic Max?

Answer 14

y’=6L/4ø₁

Question 15

What is the minimum follower width?

Answer 15

w=y₁‘-y₃’

Question 16

What is the undercutting parameter?

Answer 16

R_o=-(y+y’’)_min

Question 17

When finding the minimum base radius that prevents undercutting remember to…

Answer 17

plug in the values for the thetas at which the function is a minimum! if there is a cos term, it will be negative 1!

Question 18

What is the equation for uniform rise and return?

Answer 18

• Rise:
  
  • y₁=Lø/ø₁
• _Return:
  
  • _​same difference as always

Question 19

When given the pitch diameter of a worm gear, this represents what?

Answer 19

It is the actual diameter of the worm gear

Question 20

What is diametral pitch?

Answer 20

P=N/D=π/p

Question 21

What is circular pitch?

Answer 21

p=2πR/N

Question 22

What is the module?

Answer 22

m=D/N=p/π

Question 23

What is the circular pitch equation for helical gears?

Answer 23

p_n=p_tcosø

p_t=is the normal transverse pitch (same as circular pitch)

p_n=pitch of the hob

Question 24

What is normal diametral pitch equal to in helical gears?

Answer 24

P_n=π/p_n=π/p_tcosø=P_t/cosø

P_t=transverse diametral pitch

Question 25

What are the two equations that relate lead of a worm to the radius of the attached spur gear?

Answer 25

lead=p_xN₂

R₃=N₃p_x/2π