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Need to compress air given rotary motion input

  1. Jan 29, 2016 #1
    Hey all. I'm looking to convert rotary motion into compressed air. I'm seeing there are hydraulic gear pumps I can buy, although I'm not sure I can use them with air. Any advice? Thanks
  2. jcsd
  3. Jan 29, 2016 #2
    have you looked into swash plate pumps?
  4. Jan 29, 2016 #3
    No, I haven't heard of those. I will check them out. Seems the hydraulic pump may just be to move fluid, not compress it.
  5. Jan 29, 2016 #4
    yes sorry, i misread the original post.

    perhaps a centrifugal turbine much like that used in a turbocharger would be a good option.
  6. Jan 29, 2016 #5
    I'm now looking at piston style, you know choo choo train style :) Thanks for your input!
  7. Jan 29, 2016 #6
    There are diaphragm and bladder pumps that can pump thick viscous fluids that when run empty produce enough air pressure to fire a tennis ball through plate glass, don't ask...lol :)):woot::DD
  8. Jan 30, 2016 #7
    How about a screw type compressor or roots supercharger style compressor?

    How much air are we talking about and how much pressure and temperature? how fast a is your 'rotary motion'? Those will be a MAJOR factors in choosing the right type of compressor for your application...

    pressure ratios of 3:1 and high shaft speeds, go with a centrifugal compressor such as is found in turbochargers... they can even be compounded to provide higher pressure ratios.
    very low speed compressors? I'd go with a diaphragm type
    Medium speed? I'd go with a piston type
    higher speeds, low pressure? something like a supercharger
    higher speeds and pressures? screw compressors
  9. Jan 30, 2016 #8
    Lower speed most likely. Thanks for the input!
  10. Jan 30, 2016 #9
    Another type of pump that is good for lower pressures (a few PSI) and mid-speed applications is the rotary vane pump.. Many of the "air injection" pumps for catalytic convertor vehicles use these.. some types the vanes are forced into contact with the (offset) housing by springs or centrifugal force, others prevent close contact (thus wear) by preventing contact but keeping close tolerances by linking the vanes to an offset support bearing.. they lose a little volumetric efficiency due to leakage past the vanes, but have less friction and long life
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