Talk:Pneumatic motor

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I think one could create a CA Wikia (compressed air engine and vehicle Wikia). --Mac (talk) 15:04, 4 February 2008 (UTC)

I think that all "pure" technical information about air motors should be moved to "Air Motors". Any information about proprietary developments, particularly vehicle propulsion should have their own heading. In engineering terms an engine converts chemical energy to heat (as in a gasoline engine). Motors use their energy form directly without conversion, such as electrical motors and air motors. You don't say "I am going to put my blender engine on Frappe!", do you? If you want to verify this, talk to the PR person at Gast, one of the largest industrial air motor manufacturers. I don't think they will be satisfied that the industry that they helped develop is being redesignated by some marketing effort to equate this form of motor with an auto engine so that it will be better accepted in the market place. That issue can be put under "Compressed Air Cars". —Preceding unsigned comment added by (talk) 22:28, 23 September 2008 (UTC)

This page should not exist[edit]

It is a single purpose article devoted to Quasiturbine, which already has its own article, and yet the main topic of compressed air engines is covered in CAES. So either we move ALL that air engine stuff here (maybe not a bad idea) or kill this page. Greg Locock (talk) 09:34, 7 February 2008 (UTC)

Actually I think the first option is a good one. Greg Locock (talk) 09:47, 7 February 2008 (UTC)
So, I need to find all the stuff about other air engines (the article makes some completely ridiculous statements) and stick it in. And then scale the quasiturbine puffery back in proportion. Greg Locock (talk) 02:22, 11 February 2008 (UTC)
It has been suggested the the recently expanded stub Pneumatic motor and the Pneumatic actuator article be merged with this article. The actuator page cites no sources and comments on the discussion question its credibility, but the pneumatic motor page does provide a reliable exploration of more technical aspects of the subject. Thoughts? —Preceding unsigned comment added by Randischieber (talkcontribs) 17:10, 13 March 2010 (UTC)

Technical details missing[edit]

  • How do you check the efficiency of air powered motors?
  15% efficiency for air engine are annouced into brackets (end of the article): it seems low. Sources?  —Preceding unsigned comment added by Ant 88 (talkcontribs) 13:49, 17 September 2008 (UTC) 
  • What is the output (in one place horse-power in another torque...)?
  • More details are needed, so that we can compare these motors to other types (electric, combustion, hydro).
  • What are the benefits and drawbacks of these engines? —Preceding unsigned comment added by Pashute (talkcontribs) 14:06, 18 May 2008 (UTC)
  • I, personally, contest this article's claim that the cylindrical piston is frictionless. This is a perjorative statement that cites an uncited Wikipedia paragraph as its source. Additionally, the source itself states that some of the air becomes heated in the engine as a result of the action of the engine, indicating that there is, indeed, friction involved. —Preceding unsigned comment added by (talk) 18:26, 5 July 2008 (UTC)

HP and torque are not competing scales, they are separate measures; not interchangeable. It therefore may not be useful or even possible to use a consistent term across the entire article.

Each motor is, naturally, unique. It is therefore impossible to compare 'these' motors to 'other types'. There are general characteristics that will hold true across most air motors, but this is like saying we need more details about combustion engines, which includes a weed-whacker, a diesel power-plant, and the gamut in between. The range is too diverse to (a) hold true for most models, and (b) include anything but the most superficial level of detail.

The most important things you need to know about any air engine are the following:

  • The power output
  • The compression rate of the input air required to achieve the output
  • The rate at which it uses that air. —Preceding unsigned comment added by (talk) 02:48, 6 September 2008 (UTC)

Creating useful work?[edit]

It creates useful work by expanding compressed air. - if it needs somebody to compress the air, which requires work, then it doesn't create useful work, it just moves it from one place (or time) to another. Totnesmartin (talk) 11:34, 10 August 2008 (UTC)

Decompression of pneumatic bladders in microgravity environments can create useful work, utilizing both the vacuum of space and if necessary thermodynamics of fluids. Aditya.m4 (talk) 21:16, 11 August 2009 (UTC)

ALL energy used to run the compressor is converted to heat?[edit]

"ALL energy used to run the compressor is converted to heat due to friction." This statement makes no sense. Obviously, some of the energy is converted into air pressure. Also, most of the heat generated by a compressor is due to compression, not friction. --Dwane E Anderson (talk) 23:49, 25 January 2009 (UTC)

Agreed, that whole section reads like OR (or more accurately stuff someone made up). Greglocock (talk) 12:17, 27 January 2009 (UTC)

Proposed merge with compressed-air engine and pneumatic actuator[edit]

The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.
The result was merge. Wizard191 (talk) 16:25, 8 November 2010 (UTC)

This article as well as Pneumatic actuator - which is a technical page, and the compressed-air engine should all be merged.

Now that this page is no longer a stub, I think it is sufficient to stand on its own.
I do support the merge of pneumatic actuator into pneumatic motor, but I don't necessarily support the merge of compressed-air engine, as I see the engine article being about their use in vehicles. Although, currently, there is a lot of redundancy that needs to be resolved. Also, if the two articles are to stand on their own, the differences need to be well defined. Wizard191 (talk) 16:00, 15 March 2010 (UTC)
Have you looked into the legitimacy of the pneumatic actuator article at all? The only comment on the page's discussion is that the page is "horribly flawed." Randischieber (talk) 23:00, 15 March 2010 (UTC)
Please could you identify good sourced definitions of p.a., p.m., and c.a.e, that would allow them to be combined, or separated. My specific concern is that an actuator is not really a motor, and that the most successful c.a.e.s are actually external (or sometimes internal) combustion engines. I think there may be grounds to combine pm and cae, but it seems stretch to include pneumatic rams in the same article, even though I once built a piece of production machinery that used a ram to drive a rotor via a ratchet. Greglocock (talk) 09:07, 16 March 2010 (UTC)
Quite right Greglocock, we really do need some RS for definitions of each. This is getting a bit out of my realm of my expertise, but around the corner from my desk are a bunch of engineers that design custom air motors, so I might talk to them. Wizard191 (talk) 12:31, 16 March 2010 (UTC)

(un-indent) OK, after doing some research there isn't any real difference between the air motors found in vehicles (as mostly outlined in compressed-air engine) and all other applications (as outlined in pneumatic motor). Compressed air engines all used one of three mechanisms to convert compressed air directly to mechanical energy: axial piston, rotary vane, or a rotary piston.[1] The underlying principle is that the energy comes from the expansion of the air and not its use to aid in another energy generating system (i.e. a heat engine). As such, they should definitely be merged. Greglocock, your observation that the compressed-air motors might in fact be external combustion engines or internal combustion engines is incorrect by their definitions. EC engines are heat engines and IC engines are...well they aren't compressed-air engines. (Do note that people have incorrectly defined a heat engine as an air engine, see this).

As far as the actuator page goes, I'm leaning toward not merging them, because an actuator does a limited motion, whereas a motor creates motion over the full 360° degrees of rotation. Note that's my definition of actuator, because neither the pneumatic actuator nor the actuator article properly define it.

Other good refs: [2] [3] [4]. Wizard191 (talk) 17:45, 16 March 2010 (UTC)

Good, so are you going to move all of the heat engines off the compressed air engine page? That is, torpedo motors, MDI's current engine, etc. Where are you going to put them? Can you find any thermodynamic reason that allows you to differentiate between an external combustion engine that uses air as its working fluid, and a compressed air engine with an ambient reheat stage like the railway engines had? Cos there isn't one. Greglocock (talk) 01:29, 18 March 2010 (UTC)
Torpedo#Compressed_air states that it is a typical pneumatic motor with a piston; definitely not an EC or IC. The MDI system is also not a heat engine, but a pneumatic motor using a piston. Therefore I'm confused as to why the merge won't work. All of the applications given on the compressed-air engine pages are of pneumatic motors. Wizard191 (talk) 16:33, 18 March 2010 (UTC)
Real torpedos use fuel in their air-engines and have for 100 years. Greglocock (talk) 00:26, 24 March 2010 (UTC)
The torpedoes are pretty cut and dry, except for the wet-heaters, because they aren't truly IC engines, but they aren't traditional pneumatic motors. This explains them pretty well and at the end states "Although also known as "steam" torpedoes it can be seen that these wet heater weapons were still primarily hot air driven with the steam providing extra energy." Therefore, this reference supports that they are still pneumatic motors, just with a twist. Wizard191 (talk) 20:59, 25 March 2010 (UTC)
I'm sorry, that article has confused you. Thermodynamically the engine is a mixed internal combustion and compressed air engine, and the majoprity of the energy comes from the fuel, not the compressed air, as you can see by comparing the ranges of a cold and hot air torpedo at the same speed. Its operating cycle is directly analogous to a supercharged two stroke diesel engine with indirect injection. Now, I have no particular problem with calling that a compressed air engine for historical reasons, but I'd suggest that such a device has little need to share a page with a pneumtaic ram, for example. Greglocock (talk) 04:41, 26 March 2010 (UTC)
Sorry for the super late reply, but I got side tracked and forgot to reply. I agree with your point that discussion of this type of torpedo shouldn't share a page with a pneumatic ram, but I think there consensus that pneumatic actuator isn't going to be merged. As for the proper classification of the torpedo propulsion system, I'm honestly sure what it really is and I'm not going to spend the time, but do you think that this one thing should prevent the merge? It's borderline compressed air engine / ICE but I don't think that should hang up the merge. Wizard191 (talk) 17:53, 8 April 2010 (UTC)
I believe the Compressed air engine page should be merged into the Pneumatic motor page under a header labeled something like: Transportation Uses. The Pneumatic motor article seems to be soundly written with more legitimate sources. The pneumatic actuator article should be labeled a stub and not considered for merging.Joseftirol89 (talk) 04:52, 23 March 2010 (UTC)
Wizard has it right, MDI is an air engine, no combustion, as are the rest of the applications on compressed-air engine. Joseftirol--I think you have the right idea for the merger. Randischieber (talk) 21:47, 23 March 2010 (UTC)
No MDI burns fuel to increase the range. They used to run a pure compressed air engine but ran into the two predictable problems - limited range and the whole thing froze up. Greglocock (talk) 00:26, 24 March 2010 (UTC)
O yeah, I just checked their product specs, looks like they are dual-energy machines. Good catch Randischieber (talk) 00:07, 25 March 2010 (UTC)
I'm not very familiar with the MDI vehicle, but I think the whole MDI topic is a moot topic. They've fallen off the planet and I don't think anything is ever going to be produced. Wizard191 (talk) 17:56, 25 March 2010 (UTC)

The above discussion is closed. Please do not modify it. Subsequent comments should be made in a new section.

Rotary vane motor[edit]

Can rotary vane motors be explained better, also axial and radial piston motors seem intresting. Finally, the Gerotor air motor also seems intresting, and turbine air motors also seem to be intresting, see

Rotary air engines seem also produced in relatively large numbers, ie see [ Halo Rotary engine] (talk) 12:44, 27 February 2011 (UTC)

Illustrations and History[edit]

The pictures of vehicles are interesting but there should also be pictures of pneumatic motors; photographs of real motors and sectional schematics illustrating the various mechanisms. There should also be a section or sections on the history of development. Eventually this article might be divided into articles, each devoted to a specific type of motor. Regards, ... PeterEasthope (talk) 16:11, 23 July 2011 (UTC)

Fraud and scams with air engines and pneumatic motors[edit]

So nobody wants to talk about that? See Compressed air car#Energine. פשוט pashute ♫ (talk) 12:04, 29 August 2011 (UTC)

Carbonic Gas Motor[edit]

Any information on these? It seems they are quite similar but use carbon dioxide gas, either from liquid or just compressed, to operate. Perhaps they should be included here also. AMCKen (talk) 01:20, 18 March 2012 (UTC)

I was thinking that a pure oxygen motor could also be mentioned. Not sure though whether there would be any changes in comparison to a regular air engine. See (talk) 14:12, 16 July 2012 (UTC)

Player pianos[edit]

Player pianos need rotary motors to power the take-up reels which accumulate the paper rolls as they pass the row of holes which sense the presence of holes in the paper as it passes by. These consist of about three to six bellows which are activated (that is, by applying vacuum to them, they collapse) in sequence. They are attached to a sort of crankshaft with offset bearings so it is made to turn as each bellows collapses. The crankshaft's rotation is usually translated to the take-up reel by a chain loop. (talk) 20:53, 3 May 2014 (UTC)


The discussion about the merger is settled, apparently, but I feel impelled to point out that "motor" and "actuator" have the same meaning. One stresses "motion" and the other "action", but they essentially point to the same phenomena. Also, linear and rotary do not exhaust the possible varieties of action. The wings of birds and bats are pneumatic motors. So are sunny parking lots and loudspeakers. (talk) 21:08, 3 May 2014 (UTC)

Rhomboidal-shaped sounds tautological to me. Shouldn't this be either "rhomboidal" or "rhombus-shaped"?

Mentioning of pneumatic motors on CO2 ?[edit]

The reference to CO2 has been reverted. Many pneumatic motors used in pneumatic tools run on CO2 though, and pneumatic motors made in the past specifically for CO2, which haven't been mentioned at any page at there are also pneumatic motors made specifically for running on CO2 (i.e. Gasparin, CÉTONIA, IDEAL, and various Bill Brown Motors and RADIGUET-MASSIOT models). It could also be clearified on the page whether most pneumatic motors (not originally intented for running on CO2) could run on this gas. KVDP (talk) 16:42, 2 July 2017 (UTC)