Hi, Sean:
I can understand your confusion
since the language in this particular patent is not as clear
as it should be . . the degree of axial movement cited - a
couple of degrees - is the allowable tilt of the oil reservoir
piston without binding. It has nothing to do with the
'anti-tilt' bearing described in Humphrey's subsequent patent
CA 2485908. The anti-tilt mechanism was developed by my
company, (Hard Suits Inc.) around the same time as my CA
1209632 patent - that patent describes the basic principle of
the rotary joint but purposely omitted the 'anti-tilt' feature
and an addition feature which was in use at that time called
the 'fail-safe' ring.
Although the Humprey patent
appears to cover an entire rotary joint - it does not. The
joint shown in the Humphrey is from my original patent, but
with the addition of the 'anti-tilt' feature and the
'fail-safe' ring. There are only two claims in the
Humphrey patent - the 'anti-tilt and the 'fail-safe' - the
rest is prior art (my prior art). The short version is that my
original patent lapsed and the owners of the company (which
was sold and re-named several times after it was acquired from
me and the other shareholders by a hostile take-over bid from
a Texas company in 1996) very much wanted to continue to claim
'exclusive patented technology' even though that was no longer
the case. Humphrey was my employee from 1985 to late 2001 and,
unbeknownst to me, cut a deal with Oceanworks (the most recent
descendant of the original Hard Suits Inc.) to 'patent' these
two features in his name - but assigned to Oceanworks,(the two
features that were not in my original patent.)
He is no longer in my employ.
The few degrees of axial movement
possible in the oil make-up section amount to about 15 degrees
in a five bearing limb - significant - but nothing like the 90
degrees of normal movement - it is made possible by 'rocking'
the piston when the reservoir is partially depleted - not
usually used and not claimed in either patent.
This pretty sketchy, but I can't
go into further detail - except to say that I am currently the
sole owner of Hard Suits Inc.
Original Message -----
Sent: Saturday, October
30, 2010 12:31 PM
Subject: [PSUBS-MAILIST]
rotary ADS joint question
Perhaps best directed at Phil, but posted to the list in case
anyone is interested:
I was looking at some of the old ADS suit joint patents, and I
noticed that the old Nuytten patent (CA 1296032) describes
a degree of freedom in axial alignment of 1.5 - 3 degrees per
joint. By inspection, it appears that this is the result of the
movement of lower member 2 in this patent, although I could be
mistaken. In any case, this permissible misalignment is touted
as a design advantage in the patent, although it is not clear
whether this allowable flex is by design intent, or merely an
unintended consequence of the assembly. In the subsequent
Humphrey patent (CA 2485908), this degree of
freedom is characterized as undesirable, and indeed the joint
described in this patent specifically attempts to eliminate it
and establish axial rigidity, in an attempt to prevent any
bending load on the joint from causing seal leakage.
Intuitively this makes some sense, although the Nuytten patent
describes a cumulative flexing ability of 18 degrees over a
seven-joint conduit; this is not insignificant. I presume that
this difference would need to be accommodated by adjusting the
wedge angles and/or rotary limits of each joint such that the
necessary range of motion of the operator is not impacted. I'm
not entirely sure what I'm asking here - other than to get some
idea of whether flex is an important design objective, or
whether it is simply the result of holding looser assembly
tolerances than a design using fully rigid joints which relies
upon joint rotation exclusively?
-Sean