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Gear shaft design

  1. Mar 5, 2008 #1
    Design the shaft assembly of gear 2 with the following information:

    The specification of the involute helical gears are as follows
    Pressure angle: 20 degrees
    Torque acting on gear 1, T1= 95500Nmm
    Number of teeth: N1= 55(gear1), N2=135(gear 2)
    Helix angle= 15 degrees
    Tooth Width b= 50 mm
    Gear quality grade:8
    Input speed n1=1450rpm
    Machine for power input: electrical motor
    Machines to be driven by the motor: push press drive
    Tooth Surfaces of both gear 1 and 2 are soft
    Material of both gears is steel
    Allowable contact stress= 570N/mm2
    Allowable bending stress= 380 N/mm2

    Detail the following calculation/ selections
    1) Gear Ebnding and contact stresses
    2) Bearing selection
    3)Key and key way design

    I don't get how u can find out the module(m), I been trying to do it for days and I just can't work my way around it, please help me...my dealine is in 2 days time and I also need to produce a Auto CAd drawing too!

  2. jcsd
  3. Mar 5, 2008 #2
    You could start with Machinery's Handbook, a visit to the Boston Gear site, and also a visit to the SDPSI site to get some ideas about the gear. For the bearings, I recommend the SKF site and one (several) of the standard machine design books, as well as Machinery's Handbook.

    Good luck.
    Last edited: Mar 5, 2008
  4. Mar 5, 2008 #3
    i think i have determint the module...I run into a problem though...I tried to work out the dynamic factor so I could apply into the eqution...the graph infront of me doesn't show the dynamic factor for grade 8 quality as it ran out
  5. Mar 17, 2008 #4
    how to choose appropriate shaft

    I need to build a kind of a test device for bicycle rims. Already attached some pictures of the design. The problem is i'm not a mechanical engineer and dont know what the principles for choosing the right shaft.

    There is a big metal drum placed in a frame and it is gonna be 130cm diameter nearly 320kg. The rims going to be placed on the yellow tilting mechanism. By applying load ( 50-100 kg on each arm)to red arms and turning the drum, rims will be tested. I will use an electrical motor which is placed outside of the frame and the transmission is gonna be with a belt. This is the basic idea. However I dont know how to calculate the diameter of the drum shaft that I need.
    I already checked the google and try to find out something similar to that "device" but couldn’t find it. There are lots of information like bending moment and torque but they are not that much easy for me to understand. I hope u guys help me.

    Attached Files:

    • pics.JPG
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