ML patent Application

[Ferric Toes]

Eric,

Some sections of track are not owned by the train company that is pulling/pushing the cars., These type of train track sections get paid per car crossing. Each car has 4 wheels per side there fore every 4 wheels is a car. Sounds like the owner of the track section was confirming the car payment reimbursment system.

Do not ask how I know , It is just some trivia that I picked up from a small railroad company that owns a 50 mile section of track here in N.C.

Very good, but not the application I had. This was for a railway in Brazil where the freight trains are very long and sometimes the couplings are prone to failure. A train may start with 100 wagons but by the end of the journey one, two, or more may be missing. Wheel detectors placed every few miles would give warning if the train left a section with less wheels (wagons) than it entered with.

Eric.

[Ferric Toes]

I want to appolgize to the forum and its members for starting this thread.

I found the patent interesting in concept. Weather you agree with the legality
or premise of any patent. You have to know where we have been, to know
where you are going. Keep reinventing the Wheel.

To Carl, Eric and Davor who I have great respect. Sorry crap was flung in your
directions.

I agree with Jerry. Threads like this are very useful as it informs us all as to what is going on in the metal detector patent world, and we can analyze it from all different angles and engineering backgrounds. I doubt, in fact, that I would have looked at this patent otherwise. Initially, I thought it was a bit ludicrous, but on further examination realise there is a serious side to it that we as researchers, designers, and manufacturers, should be aware of. The more heads we get to look at patents seriously, the better we will be able to see what we can and "can't" do. We can also post and discuss what we as individuals see as Prior Art, because much, apparently, gets missed by patent examiners.

Eric.

[Carl-NC]

I want to appolgize to the forum and its members for starting this thread.

I found the patent interesting in concept. Weather you agree with the legality
or premise of any patent. You have to know where we have been, to know
where you are going. Keep reinventing the Wheel.

To Carl, Eric and Davor who I have great respect. Sorry crap was flung in your
directions.

Nope, it's a great topic to discuss. What at first seemed like a superfluous patent may have basis, and learning is Good. The sniping had nothing to do with this particular thread, it was a personality issue which just happened to trigger my peak detector on this thread. I repeatedly asked them to take the fight elsewhere, and both refused. Both get to move on, somewhere else.

[Woody.au]

One of the issues that has not been addressed and that creates noise in the detector is the mass of metal in the coil connectors, remove the plug and socket and go direct connect.

[Ferric Toes]

One of the issues that has not been addressed and that creates noise in the detector is the mass of metal in the coil connectors, remove the plug and socket and go direct connect.

Or use a coaxial, or triaxial connector.

Somewhere recently I addressed the issue of eddy currents in a metal coil shell, but it is different to metal in a coil as it is not modulated by susceptible rocks. Bad connection between the two metal halves and the threaded collar can cause noise though.

Eric.

[ODM]

Joints between a multiple independent strand cable could be done, but that would be labour intensive and sounds like a third world job to do affordably Do some detectors with the frontend, or all electronics, closer to the search head (Ebinger?) route the actual coil wires without joints into the detector electronics, as twisted pair? The shield, if necessary, would be another factor. All coax cables I know of have a woven and/or foil outer conductor, which makes for eddy currents. A section of coax is not as bad as a piece of copper tube in tests but still noticeable compared to the center conductor alone (which would be easy to fix). Litz techniques for coax cables, or just twisted pairs and high CM rejection?

[Davor]

In my searching for an unshielded solution I learned that coax is perhaps not the best solution around, but for coils with unbalanced connection, and a shield connected to the common connection, only a coax makes sense.
If coil is used in a balanced mode, it would mean that a shield is connected to a centre tap, or non-existent. Otherwise you'll pick more static.

We could continue about the balanced coils options, but that misses the point because most of the nowadays detectors are using unbalanced connections. Litz triple braid would be a logical choice for balanced coil with centre tap, and a twisted pair for a coil without a tap, only trouble is that you don't have a detector to plug it in.

BTW, what about the aluminium foil shielding? In light of modulation by susceptible rocks it seem as an extremely bad idea. Household foil has ~16um thickness, while foil in tetra pack cartons is at ~6um. It makes graphite with all it's quirks the only sensible solution.

[moodz]

...a good ultrasonic welded wire splice can have stronger bonding than solder and less magnetic signature.
For example ...
http://www.techsonicultrasonic.com/i...id=10&Itemid=7

and I do believe the patent mentions ferrite over solder ...soooooo ... If you don't use solder for the bond then you are not infringing.

[Ferric Toes]

Joints between a multiple independent strand cable could be done, but that would be labour intensive and sounds like a third world job to do affordably Do some detectors with the frontend, or all electronics, closer to the search head (Ebinger?) route the actual coil wires without joints into the detector electronics, as twisted pair? The shield, if necessary, would be another factor. All coax cables I know of have a woven and/or foil outer conductor, which makes for eddy currents. A section of coax is not as bad as a piece of copper tube in tests but still noticeable compared to the center conductor alone (which would be easy to fix). Litz techniques for coax cables, or just twisted pairs and high CM rejection?

The Minelab mono coax and the twin coax for DD coils is a specially made Litz construction. It eliminates one big problem that standard coax has, and that is detection of the braid at the point of entry into the coil shell. Tinned copper braid is better than just copper strands, but flexing of the cable at this point tightens and slackens the strands so that the contact resistance changes. An eddy current ring is formed when the ends of the strands are soldered together to connect to the ground side of the coil winding, but the varying contact resistance between strands changes the TC and amplitude of the ring - hence noise. Litz shielded coax avoids this but you still have the problem of the soldered joint, which in a heavy cable such as ML's can be large enough to give a signal at short delays. A Litz constructed RG58 type cable should be excellent (except for low resistance ML coils) but would have to be specially made.

Some coaxial audio interconnects boast Litz type construction and low capacitance, so there might be something there that would do.

Eric.

[Davor]

RG58 regularly comes as tinned copper braid. A couple of metres even of thinner cable would not make much difference in total resistance.

[Aziz]

...a good ultrasonic welded wire splice can have stronger bonding than solder and less magnetic signature.
For example ...
http://www.techsonicultrasonic.com/i...id=10&Itemid=7

and I do believe the patent mentions ferrite over solder ...soooooo ... If you don't use solder for the bond then you are not infringing.

Bad, really bad boy! Take your pills, praise and love ML as I did so.
Speak with me now:
"I love ML and their patents!
I believe in ML and their goodwill!
Long live ML!"


Love your comment Moodz!
Aziz

[bklein]

Boy aren't you in for a surprise.
This is best demonstrated with a ground balancing PI detector. Place the coil flat on the ground away from metal, then place a coin on the ground at a distance from the edge of the coil where it would be detected if moving. The coin will then give a response if you pass a soft ferrite rod over the coin even though the coil and coin are both stationary.

As said before, a coil containing excess metal will have you digging ghost signals in mineralised ground that don't exist if using a properly made coil.

Hey, a new pinpointer design.

But for the metal in the coil to have an effect on the detection, there has to be a moving magnetic field. So it brings more sensitivity to ferrous materials in the ground - but only if there is coil movement. So does that mean if we want to find meteorites we put a metal piece on our coil? Or is it really that different than if there is no metal on the coil - because the coil is moving in both cases?

[mikebg]

Bad, really bad boy! Take your pills, praise and love ML as I did so.
Speak with me now:
"I love ML and their patents!
I believe in ML and their goodwill!
Long live ML!"


Love your comment Moodz!
Aziz

I love Prospector_Al and his patents.

7,701,337 - Hybrid-technology metal detector
7,701,204 - Metal detector with reliable identification of ferrous and non-ferrous metals in soils with varying mineral content
7,656,153 - Metal detector with improved receiver coil

I believe in Prospector_Al and his goodwill!
Long live Prospector_Al to make a lot new patents!

Love your comment Aziz on the KISS principle!

[Paul99]

I love Prospector_Al and his patents.

7,701,337 - Hybrid-technology metal detector
7,701,204 - Metal detector with reliable identification of ferrous and non-ferrous metals in soils with varying mineral content
7,656,153 - Metal detector with improved receiver coil

I believe in Prospector_Al and his goodwill!
Long live Prospector_Al to make a lot new patents!

Love your comment Aziz on the KISS principle!

And there is another patent Prospector_Al has:-

http://www.geotech1.com/forums/showt...ht=20080150537

[Paul99]

And there is another patent Prospector_Al has:-

http://www.geotech1.com/forums/showt...ht=20080150537

A quick search of the US patent office brings up nothing, so, looks like this patent has lapsed. I wonder if it didn't work.