On Sun, 25 Dec 2016 18:44:58 +0000 (UTC), Frank Baron advised:
Restating the question to ask if anyone here can tell us what the patent says about the single-torsion spring setup...
The problem everyone with a clutch has on 3rd-generation Toyota 4Runners, Tacomas, and Tundras is that the Toyota dealer seems blissfully unaware of the clutch pedal squeak root cause during the warranty period.
So the dealers simply grease the $5 nylon P bushing and delron Q bushings, but by the time the squeak occurs, the $100 clutch pedal P-tab groove is already starting to be destroyed, eventually taking with it the $100 clutch pedal bracket holding the two $5 Q bushings.
So most of us have redesigned the Toyota clutch-pedal return assembly to remove the extremely complex (geometrically) torsion spring and replace it with a far simple linear spring setup.
We've also redesigned the P and Q bushings, using better materials:
But they still fail within two or three years.
We're currently at the stage of trying to *understand* why Toyota engineers used such a horrifically complex clutch-pedal-return mechanism, which we need to know if we're going to assess the long-term impact of our redesign.
We only recently found the patent, which shows a mechanism almost exactly the same as ours, so, at this point, we're just trying to understand the patent wording with respect to the single-spring function because we have been re-designing the single spring setup using a variety of methods:
The reason it matters is that the patent shows both a two-spring and a single-spring mechanism, where we presume the two-spring mechanism operates in both directions while we can intuit that the single-spring mechanism operates only in one direction.
But is that the case?
We don't know, simply because we don't understand the language of the patent.
Do you?
Specifically, what is the patent saying the single-spring apparatus accomplishes?