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Swl of a motor

  1. Aug 7, 2012 #1
    using the following information can anyone tell me if the detailed motor is capable of lifting 90kgs 48"

    Nominal speed 40 rpm
    Nominal torque 5 Nm
    Nominal voltage 12 V
    Shaft diameter 9 mm
    Manufacturer part no. DO 111.3761.2B.00 / 3018
    Specification DC gear motor
    Nominal current 5 A
    Shaft design With key 3
    Type DO11137612B00/3018

    http://www.conrad-uk.com/ce/en/product/198458/DOGA-DO11137612B003018-12VDC-Motor-40RPM-5NM-DO-11137612B00-3018/1101101&ref=list [Broken]
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Aug 7, 2012 #2


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    Staff: Mentor

    Depends on how fast you want to lift it.
  4. Aug 7, 2012 #3
    takes about about 10-15 seconds with current motor
  5. Aug 8, 2012 #4
    Describe the lift mechanism (i.e., rope on a drum, like a winch), including dimensions.
  6. Aug 8, 2012 #5
    I will be using nylon tape 25mm wide which coils onto a small drum approx 30mm i/d 75mm o/d

    http://www.bruno.com/vehicle-lift-take-apart-lifts.html [Broken]

    this the hoist mechanism
    Last edited by a moderator: May 6, 2017
  7. Aug 13, 2012 #6
    any ideas people? trying to save a disabled guy £450
  8. Aug 14, 2012 #7
    Your downward force is 90*9.81 N (call it 900) so if your drum is .037 m radius you need a torque of 33.3 NM so you'd need a 7:1 reduction gearbox.
    To raise 90 Kg over 1.2 M you need about 1000 J, 12V*5A is 60w so it would take slightly over 15 seconds for the lift.
  9. Aug 14, 2012 #8
    thanks jobrag
    thats brilliant
  10. Sep 20, 2012 #9


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    Gold Member

    I have a question please. If this was an application with a rope wrapped around the drum, would we not consider the diameter of the rope in addtion to the radius of the drum to back calculate the force necessary?
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