Talk about serendipity. I was working on another invention and was looking for some user positional tubing to make a functioning prototype. I drove north to Temple, Texas and met with an engineer at Templas Plastics, Inc. He mentioned that there was a product that was being used by machinists that might work for my prototype. When machining is being done the tools (saws, drill bits, & etc.) are expensive and the machine operators want them to last as long as possible. When cutting with the tools excessive friction overheats them and causes their cutting edges to become dull. To make them stay sharper and last longer the cutting surfaces are drenched in what is called a “cutting solution.” This liquid solution bathes the tools cutting surfaces cooling them and lubricating their cutting edges. There are user positionable conduits with nozzles on their ends that allow the machinist to direct the cutting solution exactly where they want it. These conduits are composed of hollowed out ball and socket joints that are snapped together. The hollowed out interiors line up and form a channel for the cutting solution to pass through.
The fellow from Templas Plastics directed me to a shop where I purchased some sections of these ball and socket conduits.
I was sitting in front of the TV playing with them and I noticed that they supplied a resistance when they were moved. I got a good forearm and wrist workout just sitting them playing with them. However, I noticed several drawbacks to the conduit that I was using. First, it was noisy – it squeaked every time it was manipulated. Second, it didn’t stay together very well – it pulled apart into smaller sections easily. And they wore out, that is they lost their resistance, after only a short amount of time.
What I had discovered was a possible product that would supply “consistent resistance” over a range of motion. I went to my patent Attorney, Joe Long, and he did a patent search to see if the idea had been protected with a US patent. The search appeared to be clean and so we filed a patent application on the concept. Then we waited until the patent office issued our patent.
So, to make the HeartFlex, the task was to produce a product that would be quiet, stay together, and function over time. This quest took many twists and turns but finally, after about a year I found a company who could produce what was needed. The plastic for the ball and socket joints is very modern and expensive and is a special order. The molds that make the ball and socket joints are protected by two patents and have a special design which helps the assembled pieces stay together.
The next situation was how to design the collars that the conduit attached to. The design was pretty easy. I am trained as a professional architect and my background really helped me conceptualize the shape of the part. One of my previous inventions had also introduced me to a company, Concurrent Design, here in Austin, which performs CadCam (computer assisted design). During this time I interviewed many different plastic molding fabricators and settled on Stellar Plastics, located in San Marcos, Texas. Working with the assistance and knowledge of the plastic fabricator was invaluable. We developed a single part that would connect to both the male and female ends of the conduit. This saved considerable money in the tooling because we needed only a single mold. The tooling (this is what the mold that shapes the piece is called) was around $24,000. By only having to make one tool it saved double that expense.
Next was figuring out how to affix the collars and conduit together. This proved to be very difficult. The conduit had self-lubricating material blended into its material. Nothing stuck to it, and I mean nothing. I even sent some of the material to Plexus, which is the largest manufacturer of adhesives in the world. They tried all of their different glues. Some of the glues even had acid in them that would “craze” the plastic first and then bond it. These didn’t work either. We finally settled on a specialized machine that molecularly bonds the conduit and collars together using heat. To make the bond substantial enough to hold the loads and yet not make the part deform from too much heat was a challenge. To make the molecular bond work we had to manufacture the collars out of the identical expensive plastic that the ball and socket conduits were made out of.
To save money on the tooling for the collar and to save on the expensive plastic I had the handles made out of thick wall PVC (an inexpensive plastic). This ended up not saving much money because we had the find a product that would glue the PVC handles into the collars. Hot glues worked well for manufacturing on an assembly line but they also let go if they were reheated. I knew that some folks would leave their HeartFlex in the sunlight (on the dashboards of their cars or on the rear deck where it can get really hot, especially here in Texas) and that the glue would soften, the handles would pull out, and glue would get over everything. We needed a hot glue that would not let loose when it was reheated. 3M makes a hot glue that reacts with the moisture in the atmosphere to make it inert. After several days the hot glue absorbs the ambient moisture in the atmosphere and “cures” so that it will not soften upon reheating. We only need a couple of drops per handle yet this glue, because it is very special, is also very pricey. The two drops cost us about fifty cents per handle.
Each HeartFlex is assembled in stages. First, a single collar is attached to one end of the conduit. Then a rubber conduit cover is inserted over the conduit. Next, the other end of the conduit has another collar attached to it. Both of these attachments are done individually on the machine that molecularly bonds the surfaces. All of this work is very intensive and is performed with “gloved hands” as the oil from human skin will ruin the functioning of the HeartFlex endoskeleton.
Rubber handles are then placed over the plastic handles and end caps are inserted into the end of the handle tubes.
Each HeartFlex is tested throughout this assembly process and then it is hand tested again before it is placed in its box for shipping.
There are 27 parts to each HeartFlex. The 19 ball and socket joints along with the two collars are specially manufactured precision parts.
It took over three years from initial conception to final product.
Each HeartFlex is hand made and tested. We stand behind the quality of our product. If for any reason you are not completely satisfied with it, simply return it for a full refund (including any applicable shipping) or exchange.
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