HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
<<  <  Page 4/5  >  >>
armorris
User Rank
Platinum
Invention disclosure form
armorris   9/20/2012 9:07:43 AM
NO RATINGS

The invention disclosure form is a document produced by my former employer's legal department to meet the requirements of the patent office. Besides the signatures of the inventors, the document requires the signatures of two "witnesses" to whom the invention is disclosed. Since I was already laid off when the form was emailed to me, I was unable to find qualified witnesses to sign it. I still have the pre-filled, confidential document on my hard drive.

 

I've signed many such witness forms for co-workers. I would have been given a copy of the related patent application to read and understand. My name would not have been on any of those patent applications, as a witness may not be a co-inventor. I am a co-inventor in 12 patents. The patent for the motor speed regulator would have been the second one, of which I would be the sole inventor. My co-workers were all mechanical engineers.

armorris
User Rank
Platinum
Company confidential information
armorris   9/20/2012 9:06:33 AM
NO RATINGS

I did not give out the name of my former employer, or what the invention was that employed my speed regulator algorithm, in order to avoid potential problems from them for publicly disclosing "company confidential information". Instead, I made reference to a public document that contains that information. The patent application also supports my claim that I invented the speed regulator algorithm. The patent lawyers did a "prior-art" search and would have discovered if someone had patented or tried to patent it before me. For those not familiar with patent searches, here is the link to the aforementioned document:

 http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220030107341%22.PGNR.&OS=DN/20030107341&RS=DN/20030107341

 

BTW, you need a TIFF viewer to view patent images (but not needed for text). Here's what I use and it's free. http://www.alternatiff.com/

armorris
User Rank
Platinum
Floor sweeper information
armorris   9/20/2012 9:05:18 AM
NO RATINGS

The make and model number of the floor sweeper that I believe uses my speed regulator algorithm was not given out in order to avoid potential problems from the manufacturer for publicly disclosing details of their design. Anyone interested can contact me individually for that information. If you like, I'll send you a JPG copy of the hand-drawn schematic and a PDF copy of the user manual (or the link to it). It's a good example of another use of the speed regulator algorithm, and how to interface with it. For example, the floor sweeper uses a pushbutton to sequentially select one of three fixed speeds and has three speed-indicating LEDs, using just an 8-pin PIC.  I don't have access to the sweeper's code-protected software, but I used a digital oscilloscope to observe its operation.

armorris
User Rank
Platinum
Just sit on it
armorris   9/20/2012 9:04:00 AM
NO RATINGS

I'm glad the patent application failed. I wouldn't have gotten any money from it anyway, but at least now, people are able to use my idea. My former employer would have used it in a very limited application, if at all.  It's common practice for big companies to patent ideas that they're not going to use and then sit on them to prevent competitors from using them. That's probably why they tried to patent my invention, even though they didn't really want or understand it. If they really wanted it, they would have assisted me somehow in getting witness signatures on the disclosure form (explained later) when I couldn't find someone, rather than let it become public domain a year later. The purpose of the invention was to replace a piece of mechanical hardware with software, saving some recurring cost in a mass-produced product. This proved to be much more complex than just the speed regulator.

armorris
User Rank
Platinum
Silver platter
armorris   9/20/2012 9:02:40 AM
NO RATINGS

I believe that when my former employer closed the facility where I worked before the final step in the patent process could be completed, they effectively served my invention to the sweeper manufacturer on a silver platter. The timing is right and the patent office is the first place someone would look, who was looking for a cheap motor speed regulator for a consumer product. Even if the sweeper manufacturer intended to develop their own motor control, they almost certainly would have done a patent search first in order to avoid creating a costly patent infringement. But then, something like this probably happened: "Hey, check this out! Here's just what we need, and for some reason it didn't get patented. It's now in the public domain and a prior-art search has already been done. Wow! Let's grab it!"

armorris
User Rank
Platinum
Patent issues
armorris   9/20/2012 9:01:25 AM
NO RATINGS

This gadget is not just about motor speed regulators, it's also about patents. I worked for 5 years in a R&D (research and development) center, where I developed the motor control algorithm and where we worked with patents every day. I had been a member of an inventor's club for about 15 years before that. There may be a lesson here for other gadget makers who hope to patent their inventions. I hope to spark some conversation on the subject of patents, as well as the gadget itself.

armorris
User Rank
Platinum
Gadget inspiration
armorris   9/20/2012 9:00:06 AM
NO RATINGS

My lifelong interest in motor speed regulators (also called governors) began in high school in the 60's, when I had a cassette recorder, a portable record player and later, an 8-track tape player, all with faulty mechanical governors. I eventually figured out how the cleverly designed Philips (Norelco) governor circuit worked. Most manufacturers wouldn't pay Philips for the rights to use their patented circuit. I repaired cassette recorders and 8-track tape players for other people by bypassing the mechanical governor and adding my version of the Philips governor circuit. The simple two-transistor circuit was easy to build and tuck away inside the set. Nowadays, cassette recorder motors have built-in governor chips.

 

 Back in 1987, I designed a "bang-bang" motor speed regulator using a 555 timer and was disappointed to discover that it was no more efficient than a linear regulator.  For a fixed speed and load, the current draw remained constant with changes in the power supply voltage. The motor got warm instead of the output transistor. The 555 timer turned the motor on for a fixed period of time whenever the motor's BEMF dropped below a certain level. The hardware configuration was very similar to that used in this gadget. The patent application referenced in this article explains "bang-bang" motor control in much more detail. BTW, the aforementioned mechanical governors are examples of "bang-bang" motor control.

armorris
User Rank
Platinum
If you need a PIC
armorris   9/20/2012 8:58:46 AM
NO RATINGS

Please email me if you want to build this gadget and don't have the means to program a microcontroller. If you live in the US, I'll send you a programmed PIC for the cost of the blank PIC and estimated postage (unless that practice gets out of hand). Just let me know whether you intend to build the full-sized or the in-line version of the control, so I know whether or not to disable the overload timer. I'm sorry that I have no PCB (printed circuit board) artwork to give to you for either version. Due to the circuit's simplicity, a PCB layout should be very easy to do. I find it easier to hand-wire something than to make a PCB if I'm only making one copy of it. Hand wiring also gives me more packaging flexibility. If you create a PCB layout for it, please share it.

armorris
User Rank
Platinum
In-line version of speed regulator
armorris   9/20/2012 8:56:51 AM
NO RATINGS

After this article was written, I created an in-line version of the digital speed regulator. Experience with the circuit so far has shown the minimum speed setting to be perfect for my needs. Sometimes it's also handy not to have a control box in the way when not working at a bench or table. The tiny in-line version has no knob, switch, or LED and runs at one set speed. This required disabling the overload timer as there is no quick way to reset it without the on-off switch. The user must take care not to keep the motor overloaded for an extended period of time. The mini-drill will probably get noticeably warm before there is risk of damage.

 

The circuit was built onto a tiny piece of perfboard, 4 holes by 18 holes in dimension and covered with heat-shrink tubing. Please email me if you would like construction details. My email address is in the article.

armorris
User Rank
Platinum
Resolved overload protection issue
armorris   9/20/2012 8:55:24 AM
NO RATINGS

You can see in the video that when the mini-drill itself was switched off, the overload LED came on and had to be reset by switching the control unit off and then on with the tool itself on (or switched on within 3 seconds). This is caused by the fact that when the motor is disconnected, the circuit does not see the feedback from the motor and thinks that the motor has stalled. I was aware of this when I designed it, but I didn't see it as an issue until I used it for the first time on a real job, restoring an antique cigarette lighter. It became a bit of an annoyance. The switch on the tool is much more convenient to use than the switch on the control box. I solved the problem after the video was made by adding a resistor (R10) to fool the electronics into thinking that the motor is still connected and running at full speed when the motor is actually disconnected. Due to the extremely low relative resistance of the motor, the resistor is effectively bypassed when the motor is connected and has no effect on circuit performance.

 

I also changed the software code to boot-up at zero speed, instead of max speed as was the case in the video. You may have heard it start up at high speed and then very quickly come down to the set speed. This "up-to-speed" help was not needed due to the fact that the motor is unloaded at start-up. In the invention for which this algorithm was originally created, the motor was started up under load, requiring this extra boost. This change has no effect on the gadget's performance.

<<  <  Page 4/5  >  >>


Partner Zone
Latest Analysis
Some of our culture's most enduring robots appeared in the 80s. The Aliens series produced another evil android, and we saw light robot fare in the form of Short Circuit. Two of the great robots of all time also showed up: The Terminator and RoboCop.
Two students have created a voice-command system for our homes, based on the simple and affordable Raspberry Pi.
Optomec's third America Makes project for metal 3D printing teams the LENS process company with GE Aviation, Lockheed, and other big aerospace names to develop guidelines for repairing high-value flight-critical Air Force components.
This Gadget Freak review looks at a cooler that is essentially a party on wheels with a built-in blender, Bluetooth speaker, and USB charger. We also look at a sustainable, rotating wireless smartphone charger.
Texas Instruments is rolling out a new microcontroller that could make the design of sensor networks and data logging systems simpler and less costly.
More:Blogs|News
Design News Webinar Series
7/23/2014 11:00 a.m. California / 2:00 p.m. New York
7/17/2014 11:00 a.m. California / 2:00 p.m. New York
6/25/2014 11:00 a.m. California / 2:00 p.m. New York
5/13/2014 10:00 a.m. California / 1:00 p.m. New York / 6:00 p.m. London
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Aug 4 - 8, Introduction to Linux Device Drivers
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  6


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Next Class: August 12 - 14
Sponsored by igus
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Copyright © 2014 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service