Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations waross on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Recent content by bernardg

  1. bernardg

    1/4-20 'thread forming' screw

    Thanks for your prompt replies. Other data that might help you to understand this better... On 2 motors, I torqued the casebolts to 125 in-lbs... and I allowed those motors to sit for 1 week. Then, i measured the backout torque. It measured 55-57 in-lbs. on 2 motors, I torqued the casebolts to...
  2. bernardg

    1/4-20 'thread forming' screw

    Hello All, We manufacture the dc motors. And for attaching the end frames and the shell, we plan to replace the bolt & nut assembly with the self-threading screws (thread forming). We use 2pcs of 1/4-20 'thread forming' screw to drive it into a blind hole in the casting. (The thread-forling...
  3. bernardg

    Moment of interia of an armature

    itssmoked, As I mentioned before, the last testing was done just with the blower-wheel assembly, without putting them into the double scroll blower. The wheels have both the inner ring and the outer ring (inner ring has the shaft hole into which the armature shaft goes into)... and all the 20...
  4. bernardg

    Moment of interia of an armature

    Electricpete, I am going to take this one step at a time. First i am gonna start to calculate the angular acceleration of the armature: Looking at the equation that you wrote for finding out the angular acceleration of the armature when slided down a small ramp... We can control the linear...
  5. bernardg

    Moment of interia of an armature

    Thanks for all your prompt replies. I very much appreciate it. As I've mentioned before, all these discussions are on the armature as is... and not inside a motor. The mtr-wheel config would look kinda similar to this... ___________________________________________blower housing ___...
  6. bernardg

    Moment of interia of an armature

    Thanks for all your prompt replies. I very much appreciate it. As I've mentioned before, all these discussions are on the armature as is... and not inside a motor. The mtr-wheel config would look kinda similar to this... ___________________________________________blower housing ___...
  7. bernardg

    Moment of Inertia - armature

    Hello All, We make 3.0" DC motors... and for some blower applications, we mount the wheels to the shaft and assemble the motor-wheel into blower housings. Because of the tight clearance that we maintain between the wheel and the housing... even when the motor shaft flexes a little due to the...
  8. bernardg

    Moment of interia of an armature

    Hello All, We make 3.0" DC motors... and for some blower applications, we mount the wheels to the shaft and assemble the motor-wheel into blower housings. Because of the tight clearance that we maintain between the wheel and the housing... even when the motor shaft flexes a little due to the...
  9. bernardg

    displaying a jpeg image in GUI

    Hello, I am a mechanical engineer... and I am not very familiar with the MatLab. This is a very urgent project... and I very much need your help... Question: While working with GUI, I am trying to read a jpg or jpeg file. All I have to do is... If I click a push button, I need to display a...
  10. bernardg

    Two-plane dynamically balancing

    Hello All, We make dc motors... and for a new application, we need to assemble the blower wheel to our motor shaft and have them dynamically balanced. The config will look something similar to this... |-----------| ___ Motor----------------|___| |-----------| shaft blower...
  11. bernardg

    self-aligning spherical bearing

    A quick question to all the pundits out here... what exactly is it about the larger self-aligning spherical bearing that makes it better than the smaller self-aligning spherical bearing? I've heard a few people here and there mention its superiority, but what I want to know is why. Is there...
  12. bernardg

    accelerated life test on the bearing

    To answer your questions... As you know, in a dc brush motor, the primary failure mode is usually the brush wearing out... and NOT bearing reaching the end of its life. We are currently buying the bearings from NTN. Because of the cost implications, we are trying to find a cheaper source...(a...
  13. bernardg

    accelerated life test on the bearing

    Hello all, We make dc motors... and as you know, bearing is a part of the motor system. We use 608 ball bearings. Mostly, in the field... the bearings would take the radial (side) load... and a little axial load, depending on the application in which they are used. Right now, we are trying to...
  14. bernardg

    FEA TOOL

    Hello all, Thanks for your replies. One last question... We have decided to go with the MSC software. They have sent me a quote for "MSC.visualNastran 4D for SolidWorks" Have any of you have prior experience working with this tool? For the requirements that I mentioned previously in this...
  15. bernardg

    FEA TOOL

    In a nutshell... We manufacture permanant magnet dc motors... and our motor need to pass the 10G random vibration test in the 3 perpendicular planes, w/ the shaker table excited at 24 - 1000 Hz. (The motors are not powered up. They are mounted on the fixture that is bolted down to the shaker...

Part and Inventory Search