toggle quoted messageShow quoted text
BUT no one has answered the first question I asked -- aren't
almost all trucks designed this way since the 1950's ?
I don't really care what it's called. Great and useful
innovations are quickly imitated by others if not protected by a
On 4/8/2022 12:28 PM, mopacfirst wrote:
Tell me if I understand
this right. First, this kind of reminds me of my first statics
classes in 1970/71.
The first truss is the steel casting that we can easily see, the
outboard portion of the sideframe. The second truss, then, is
behind the first one and an integral part of the same casting
but which integrates with the spring package and the bolster in
a different way than the first. You gotta hand it to 1920s
marketing guys to come up with this term, but it does appear to
do what the ad claims it does, namely support the spring pack in
an additional and different way. The curved shape at the top of
the sideframe and bottom of the bolster adds to the flexibility
in the transverse direction, it appears, and it may not really
be part of that 'second truss' but a design improvement just the
same. And if it adds to the decreased point or line loading on
the casting edges at different places, obviously a good thing.
The Taylor truck with circular interface between sideframe and
spring-bolster assembly is perhaps another attempt to solve the
same problem, or at least one of them.