My apologies for putting this in the REVIEW forum, but it seemed like the best place until we get the ARTICLE section going on the main site. This is a copy of an article I posted some time ago on another forum. It seems that there is some new interest in the subject, so I am posting it again here for convenience.
~Bob We’ve looked at quite a few different old multi tools that came and went in the decades before the Leatherman Personal Survival Tool was introduced. So what do you think? Was Tim Leatherman’s invention a truly new idea, or was it simply a copy and natural progression of tools from a previous generation? We may never know for sure, but one thing is certain; Tim Leatherman’s early plans and ideas were a lot more ambitious than the PST design which eventually reached the marketplace in 1983!
According to the
HISTORY page at the Leatherman Tool Group website, Tim was awarded the first of his many patents in the year 1980. That patent was first applied for in 1978, and eventually became United States Patent number 4,238,862. Note that this tool only bears a passing resemblance to the PST which we are all familiar with:
If you are anything like me, the first thing that comes to mind when seeing the sketch above is something along the lines of, “What in the heck is that contraption?!”
Good question. After considerable study, I think I’ve got it figured out.
Take a look at the picture below, which I “cleaned up” a bit. One has no trouble comprehending the assembly near the bottom of the sketch. The fanned-out bouquet of knives, scissors, files, screwdriver blades, etc looks just like every other multi tool on the market. But what are those extra flappy appendages near the top, up by the plier jaws?
In a nutshell, detail #36 is one of a pair of needlenose jaws, that slip over and are engaged by the #23 regular jaws when needed. When they are NOT needed, these retractable needlenose jaws fold back and out of the way into the #15 handles. Too cool!
What about that #50 thingy hanging off the left side? That, my friends, is a plier-locking mechanism, which turns this early Leatherman into a tool similar to a pair of Vise-Grip pliers. No kidding! It too nests into the handles when not needed. But when you want to lock the jaws (either set of jaws) onto something, you simply swing it over to the right-hand side, engaging the #56 pawl into the #55 serrations along the edge of the handle. The plier jaws are now locked like vise-grips. Shazam!
Here are some more sketches from the patent:
FIGURE 1 shows the tool all folded up, with an x-ray view of how the jaws would nest together inside the handles.
FIGURE 2 is the same as the one up above, but more cluttered with all the detail numbers.
FIGURES 3 and 4 show the edge of the handles, with the tool in the folded-up position. Note how the handle on the left is thicker than the one on the right. This is because it needs to house the #50 locking-bar device. Also note the “bulge” #65 which is needed to accommodate the #56 pawl we talked about earlier.
FIGURE 6 shows the blade locking method. This is quite ironic, given that the original PST never had locking blades! Not until the Leatherman Super Tool came along
ELEVEN YEARS LATER in 1994 was this blade locking feature offered!
FIGURES 7 and 8 show x-ray views of how the #36 needlenose jaws are engaged by the #23 regular blunt jaws. Apparently the user would flip the needlenose jaws down onto the blunt jaws while the latter pair were partially open. Then, as the plier was closed, the blunt jaws would engage into hollow recesses within the needlenose jaws. Hmmmm, interesting.
FIGURE 9 shows the needlenose jaws clamped down onto a small piece of material #51. The tool is in Vise-Grip mode, with the #50 locking bar swung over and the #56 pawl engaged in serrations along the handle. (Actually, this FIGURE 9 is kind of crowded and confusing. The locking method is easier to see and understand on the next page, FIGURE 17.)
FIGURE 14 shows the locking bar pawl #56.
FIGURE 12 shows an edge-view of the locking bar pawl #56 engaged in the serrations.
FIGURE 13 simply shows how to put the handles together end-to-end in order to have a 7” ruler.
FIGURES 15 and 16 are more x-ray views of how the needlenose and blunt nose jaw mechanism works. Evidently there are little pins #45 that keep the two sets of jaws oriented to one another. (They look somewhat fragile to me.)
FIGURE 17 shows the tool in Vise-Grip mode again, this time with the blunt jaws clamped onto a nut. I’m guessing a person is supposed to grip the two plier handles together tightly, achieving some degree of “over-flex” in the handles. Then the locking bar #50 is pressed in until the pawl #56 ratchets up to some place along the serrations #55. When the user then relaxes his grip on the handles, the locking bar and pawl take up the load, keeping the plier jaws clamped onto whatever is between them.
Patent number 4,238,862 then goes rambling on with another five more pages of text. The combination of legal and engineering jargon attempts to explain how the entire mechanism is supposed to work. It is mind-numbing. I cannot force my brain to understand what is trying to be said, and so did not include those pages in this report.My conclusion? Tim Leatherman certainly had some very ambitious ideas back in 1978! Now 28 years and several million multi tools later, the mega-Leatherman Tool Group still has not employed a couple of his very first ideas. Maybe those retractable needlenose jaws and locking side bar are not practical? Or, you say, maybe they are not even POSSIBLE?
Hmmmm, go back to those pictures on the Leatherman
HISTORY page. Click on the (1979) or (1980) date icon and look very closely at the pictures. Do you see what I see?
Where can I get one of those tools!~Bob
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