The Takahashi Permanent Magnet Motor

Primary reference:— 

Japanese Patent JPS62114465.

Here are the images from what must be one of the simplest permanent magnet motors ever patented:—

(I have tidied up the labelling a bit, on the first image).

These are from Japanese Patent JPS62114465. At least, that is its current classification on Espacenet (the European Patent Office, at http://worldwide.espacenet.com/), who, for whatever reason seem to like to change classifications at times. Originally they listed this patent with no "S" in its classification.

Abstract

Here is the English-language abstract of JPS62114465, quoted verbatim:—

"PURPOSE: To execute continuous rotation without requiring the supply of external energy, by using diamagnetic soft substance having the characteristic of high saturation magnetic flux density, high permeability, and the like, as rotor material.

CONSTITUTION: A motor 1 is organized with a stator 2 made of a horse-shoe type permanent magnet, and a rotor 3 provided with a rotor shaft 4. Diamagnetic soft material having the characteristic of the high saturation, high permeability, and small coercive force of an amorphous alloy including the base of cobalt and the sub material of iron, nickel, molybdenum, boron, and silicon is used for the rotor 3. Then, by the motor 1, the rotor 3 is just started and rotated from an external section at the beginning, and after that, the rotating output can be retained without requiring the supply of external energy."

Comment

It seems that if the rotor material has special enough properties, this device will work perpetually as a permanent magnet motor — or so the patent claims. Needless to say, no material like this is generally known to exist.

Why bother with this?

Of course, patents claiming to extract energy in one way or another from permanent magnets are quite numerous, and generally worthless. So why am I paying any attention to this one?

The reason is that the inventor is none other than Yasunori Takahashi. Takahashi was a major "player" in the electrical engineering industry, rising to General Manager research and development for Sony Corporation, before leaving to found his own company in 1984. In fact, since I'm doing some verbatim quoting in this post, here is his entire CV, from Infinite Energy magazine, Vol.1, No. 5/6, 1996, p35:—


Curriculum Vitae

Yasunori Takahashi
Todoroki, Setagaya, Tokyo, Japan.

Date of Birth: 10th. Oct., 1940.

Education:
3-1963   Graduated from Tokyo University
12-1965  Study at Washington University (Electrical Engineering)
6-1966   (M.E.) Washington University

Work:
4-1963   Sony Corp. (2nd. Engineering Dept.)
              Design & development of
              transistor
              transistor TV and radio
              chromatron
12-1965  Research for Ceramic High Tension Condenser with Murata Manufact. Co.
1-1966   Development of Chromatron for military use with Automeix (RCA)
              Experimental Colour TV
1967      Research & Development for Trinitron colour TV
1969      Trinitron colour TV
              Development of Beta VTR
1970      Beta VTR, Omega Machine for NHK
1971/1976  Stayed in Europe & USA for setting up factories.
1977      Development for Magnetic Camera, Mabica
1982      Mabica
1983      Resigned from Sony (General Manager for research & development)
1984      Founded Scitek Co. Ltd.
              Act as consultant for
              Kodak (Video)
              Faiser Magnetic (Coating materials for video tapes)
1986     Changed the company name to Sciex.
1993     Invented YT Magnet
1994     Founded Sciex (UK) Ltd. (Director, R&D)


Yasunori Takahashi is one of the most interesting personalities to become involved with perpetual motion or "free energy" magnet motors. I'll devote a future post to his even more provocative "Self Generating Motor".

Questions

Years ago I wrote a polite letter to one of the individuals who had endorsed the Kawai magnet motor (see the video I posted on this at https://www.youtube.com/watch?v=J61m6YY-2sY) asking for more details about its performance, etc. Needless to say, with hindsight, I got no reply, and I came to realise that any such questioning, from members of the public, is futile.

Still, I often think we would be so much further ahead, in so many areas, if only those who could answer questions fully and honestly would actually do so. Of course I realise there are many possible reasons why they don't, which I won't discuss further here.

Anyway, for what it's worth, my questions for Takahashi would be:—

1.  Did you build a prototype of the motor patented in JPS62114465?
2.  If so, did it really work as described?
3.  If so, is it still available for examination and testing?
4.  If it is no longer available, would you be prepared to specify, and supervise the construction of another prototype (assuming agreement could be reached on costs)?
5.  If you didn't build a prototype, or it didn't work, what was the point of applying for, and getting the patent?

"Wedgerep"

Analysis of the original 12-magnet + shield "Repmag" idea showed that the attraction forces on magnets entering or exiting the shield were far larger than the repulsion forces between adjacent magnets, and could potentially cause problems, as discussed previously.

A repulsion-only device

I decided to investigate a development of this idea that would have no attraction forces at all — only forces of repulsion. See below:—

"Wedgerep" magnet motor

This model has two thin full-circle drum rotors, one inside the other, both turning clockwise. The rotors are made of NdFeB35, magnetised radially, repelling each other. As the magnets come close together, their flux densities in that region will drop significantly, so they will not be repelled much as they enter the gap between the two semi-circular NdFeB35 stator magnets.

However, the rotor magnets are far apart as they exit from the repelling stator magnets, so they will be strongly repelled there. The question is: will the extra energy gained by this be enough to exceed the loss that must occur as the magnets close up again? In a word, the answer turns out to be "No".

"Wedgerep" showing magnetic flux densities

This flux density plot shows the magnets do behave generally as described above, but the force and torque results from magnetostatic analysis show there is no net energy gain.

A salient-pole version — but still no energy gain

"Wedgerep" salient pole version

I also analysed a "salient-pole" version of the above idea, with individual rotor magnets as shown. Once again, the drop in flux density as the magnets close up can be seen, as well as the higher flux density as they exit the stator magnets. But, as before (with a lot more analysis required), the force and torque results show there is no net energy gain.

Conclusion

It is not worthwhile to spend any more time on this "Wedgerep" idea.

Repmag Part IV

Showing a single 65 × 35 × 25 NdFeB35 magnet entering a steel shield

Examination of the results obtained from magnetostatic and then dynamic analysis of the original Repmag idea discussed in Part I suggests that, although it might be expected and "reasonable" that the energy gained by each magnet entering the shield would be balanced by the energy lost by another magnet exiting the shield, this does not actually occur. Further modelling of this in the above linear model shows that quite a lot more energy is required to extract a closed-up pair of magnets from within a shield, than is gained in total when the two magnets enter the shield separately.

This is so, even though total flux from the closed-up pair of magnets is slightly less than the sum of flux produced by two separate magnets.

This energy difference is almost (but not quite) enough to negate the energy gained from subsequently allowing the magnets to separate outside of the shield.

This result is an example of the surprises that can be encountered in detailed magnetostatic modelling of even quite simple concepts.

Another such surprise (a pleasant one this time) was the extent of the energy reduction for two magnets repelling side-by-side in air, then closing up again within a steel shield. The result for two 65 × 35 × 25 NdFeB35 magnets is 5.706 J gained (in air) vs only 0.0427 J lost, for 0.5mm airgaps between the magnets and the shield. I had not expected so much reduction, given that there is about a threefold increase in B (flux density) when the magnets are inside the shield, and that the force exerted by a magnet is roughly proportional to B². Evidently the steel shield concept is very effective in preventing flux from returning around the sides of the magnets.

The above linear model is "ideal," with zero separation between a pair of magnets throughout the entire duration of their exit — in fact some separation does occur as the magnets exit in the Repmag model. Even a small amount of separation can make a significant difference to the overall performance.

However, I would have to find a definite solution for the entry/exit energy difference problem before going further with this concept. Otherwise, the modelling done so far suggests that the concept would work only from "second-order" effects, which would be too weak to justify building a physical prototype.

For splined-spider Repmag modelling

This model was built for future magnetostatic modelling of the splined-spider approach, with radial holes in the magnets, as shown in Drawing 2 last time.