POSTGRANTREVIEW.com Notes from a Post Grant Review

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Strapping Cell Phones to Oil Wells

Two-panel cartoon: on the left, the goggled inventor in his cluttered workshop grins in disbelief that his rig actually works; on the right, a smartphone is cable-tied to the rusty rod rotator clamp of a pumping unit.
Strapping a phone to the rod rotator — and, against the odds, it worked.

The first prototype was literally a phone strapped to an oil well. The sensors were already in your pocket. How to process that signal was the hard part.

By The Inventor

Background — part of my pro se Post Grant Review of U.S. Patent 12,460,537, the patent I believe copies my work. This one is a breather and the origin story: how I built the rotation-sensing invention by strapping smartphones to pumping units — the disclosure everything else turns on. New here? Start at Dispatch No. 1.

All of this dumping on examiners (see my apology in Dispatch No. 14) and complaining about the process has got me down. There was a time when I was out inventing stuff. That was fun. Here's that story.

The oil industry isn't all bad

Some of the first mobile computers, large-scale computing, heck the concept of wavelets… I could dork out for hours. The point is a lot of innovation comes from this field. A lot of patent decisions. A lot of good people (and some bad ones). And that scene in Landman really happened, but not at all like they portrayed it. Also, I'm trying to get my dog on that show… in case anyone has connections.

You don't have to like this industry to appreciate this story. Corporate ethics are a disaster in every industry.

If you really don't like this industry, then you can root for me extra hard.

The rest of this post describes the actual invention. I probably shouldn't have waited until the 15th post to explain the technical/physical problem this invention solves.

The oil well

Diagram: a pumpjack on a grassy surface above a cross-section of the wellbore descending through layered rock strata, with the rod string running down a slightly crooked well to the pump at the bottom.
A rod pump, top to bottom — note the crooked wellbore.

Every good invention solves a problem. But first you need to know a bit about how an oil well works. There are many other types of wells, but this is the one you all think of. The pumpjack, or rod pump.

That pump has 2 simple check valves and pushes the fluid from the bottom of the well up. Every stroke cycles those valves (that direction change is why I say everyone learns this on day one). Every stroke moves a little more fluid up and eventually it gets to the surface, then to a refinery, then to your gas tank. I'm happy to answer questions.

It's called a rod pump because that thing you see bobbing up and down is connected to a long rod. A wise man once said thin joints of steel bar that are threadedly connected through couplings. What that means is the thing at surface is connected to the pump way down at the bottom of the well by a rod string.

A 'Sportsman's Pocket Saw' in its retail packaging — a thin flexible wire saw with two finger rings, pictured cutting through a tree branch.
A flexible wire pocket saw looped around a tree trunk and pulled taut by hand, with an inset showing the coiled stainless wire saw and its two rubber finger handles.
A cable saw — no teeth, but a lot of sideload.

It's called a rod string, because when a steel rod is that long it kind of feels like a floppy string. This rod string can be over 2 miles long, snaked through a crooked pipe. It's useful to think about those camping saws. That's a good analogy for the deeper problem here. That floppy string snaked through that crooked path sort of acts like this saw. It wears through the tubing by friction and abrasion — same basic concept as the saw. We want to distribute that abrasion to increase runtime.

The system

So now we have a long steel rod connected to a downhole pump at one end, and the pumpjack at surface. In a perfect world that's it, but in reality the wellbore is crooked. Every time this rod slides up and down (remember those direction changes), it rubs a little bit on the crooked part of the well. This happens 24/7, at 1-10 strokes per minute. That's upwards of a few million strokes per year. A few million scrapes and gouges wear through, which means failure, which means you need to pull all those rods out (and more), replace the worn ones, and run them all back in. It's an expensive failure.

To mitigate that wear, we slowly rotate the rods. On every stroke, the stroking action pulls up on a ratchet arm, actuating a slow gear. The goal is to evenly distribute the wear. But it turns very slowly.

The problem

Photo: the cut end of a thick steel oil-well tubing joint, its inner bore polished and worn, with a hole worn clean through the wall where the rod scraped through; a second tubing section sits beside it.
Wear-related failures. The rod literally cuts its way through the tubing.

The rod rotator mechanism turns slowly, too slow to easily see and verify visually. If you're really determined, you can watch it for a while and verify it's working, but that's very subjective. It could go undiagnosed for a long time. Heck, a lazy field tech might just phone it in and not actually look at it… you know, like — in my opinion — a certain examiner and a certain document…

Not catching this can result in an early failure like this one. There are more nuanced failures that arise, but this one is obvious. The rods sawed themselves through the tubing. Remember, wells are crooked, creating a sideload, and that stroking action (defined by those pesky 3 direction changes) slides the rod against the tubing and friction/sideload/wear all cause various failures.

The fundamental problem this invention addresses is catching a failed rotation mechanism early.

The solution is either to rely on visual inspection (unreliable… just like a certain examiner), or to use automation to sense it.

Background - the first patent

The first rotation sensing system was by Hurst, patent 9,140,113. This was a wired switch-based system that had two fundamental problems (and some not-so-fundamental problems). First, it was a wired sensor — and wires are problematic in this system, since it's constantly moving (5,000,000 times a year) and outside in the elements. The second problem is that the switch-based system required converting the trigger counts to some actionable alarm. You can't just wire in the switch, you need some extra programming on the automation to provide a useful on/off signal for a failure. Or a range signal… but either way, a counter is difficult to generate an alarm from (not impossible, just hard… and "hard" doesn't make or break a patent… but not disclosing the hard part should raise examination objections).

The solution - my solution

I can build a better mousetrap. It's slowly rotating so I can use inertial sensors to sense it. Then I can provide a simple signal based on that state.

This is something completely new. This is an invention. This is something worthy of a patent.

The R & D

Photo: a smartphone in a rugged case, zip-tied and clamped to a bracket on a rusty pumping-unit motor; its screen shows a three-axis accelerometer app graphing red, green, and blue waveforms.
Photo: a smartphone in a black case zip-tied to the rusty rod rotator clamp of a pumping unit, with the bridle's wire ropes, green-painted equipment, and blue sky behind it.
March 2017 — before the actual idea. It took 9 months to sort out the “it should be a patent” part.

This was the fun part. An idea is great, but seeing it come to life is something truly exciting. This is the kind of stuff I want to be doing. This is how we maintain our innovation edge. Imagine if there were more folks like me out there making cool things. But sadly, the enthusiasm has been squeezed out of me because the system failed to protect the very thing it was designed to protect. Me.

So here I was in March of 2017 armed only with a cellphone and a data logger app. Can I get actionable information from this? Can I sort through the chaotic nature of the system and its signal? It took 9 months for me to file my provisional. Remember, I didn't have a roadmap or a disclosure to literally copy to expedite that process. I had to do the hard part. The actual inventing. The (patent) system should have had my back. The examiner should have examined this. There were so many failures. As an inventor, I'm well used to failures.

(And the usual caveat: “the examiner should have examined this” is my grievance, not my legal argument. A PGR doesn't hinge on the examiner at all — the Board re-decides the patent on the prior art and §§ 102/103/112.)

The prototype

Stylized illustration of a pumping unit's polished-rod clamp and rod rotator with a red sensor module mounted on top and an up-arrow marking the rod, against a blue sky.
The concept: a self-contained sensor riding the rod rotator.

And here it is. That little red doohickey. Slick, compact, efficient, ready for production. (The part that made it actually work — taming that noisy magnetometer signal — is exactly the how the copycat's filing never discloses.) Then, the way I see it, I got ripped off. This is how close I was. I spent a bunch of time, effort, and money developing this with the (false) assumption that the USPTO would rigorously examine any other application that came along. It's their fundamental job. If they just did that, I wouldn't be in this mess. I might have even made some money from my hard work? Heck, who knows what other inventions I would have come up with in the meantime if I had the financial resources the USPTO delightfully passed to the non-innovative folks in this story.

I would much rather be inventing. I've had several ideas that I just gave up on because of what happened here. Why even bother? That's the tragic reality of this whole story. You all lose out on my innovation. I know that sounds awfully conceited, but think about it. I'm not coming up with some widget to improve some process or operation. Imagine if the dude who invented the lightbulb said, "Why even bother?"

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