WHY THE NEW RAZR’S INGENIOUS HINGE IS THE KEY TO HOLDING IT ALL TOGETHER
THE HINGE AT THE HEART
The real coup of the new Razr’s
engineering brilliance is partly
electronic genius and partly
mechanical wizardry: the folding
screen and thin design with no
gap when it’s closed.
“There’s an icon in people’s
head, and they just need to see it,
even at a distance,” says Castano,
of the Razr’s look. “It’s instantly
recognisable. We put a lot of
focus into trying to keep the
thickness, especially, as close as
possible to the original design.
We knew that works in terms
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the display to create a zero-gap
design. If you see other [folding
phones] that are out there,
they’re folding the display with an
air gap in the centre, which really
defeats the purpose.”
To make the new Razr close
fully in an ultra-thin design,
there’s a very elaborate and
clever hinge design. When the
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with metal plates underneath the
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So when you start to close the
new Razr’s screen, two of the
metal plates in the middle of the
display that brace it actually slide
towards the ends of the phone,
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screen actually has room to bend
itself into a loop. As the two sides
of the Razr come together fully,
the display has now formed a
kind of teardrop shape – a bit
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together without making a
crease. This teardrop shape sits
within the hinge mechanism itself,
occupying the gap left by the
moving plates – as shown in the
design sketches from the Razr
team above. And so it can close
fully without causing damaging
creases in the screen.
This meant that the hinge had
to be further custom-designed,
because it couldn’t run all the
way along the phone, since the
screen needed that space.
But it still had to be ultra-
stable, because any misalignment
between the two sides would
cause big screen problems. The
hinge is only connected at the
left and right of the screen, with
long arms that stretch right up
the length of the device, to keep
it rock steady and stable. Its
mechanisms are treated with a
“diamond-like coating” that
Motorola had to work with its
suppliers to come up with, to
make the gears ultra-hard, so
they won’t wear over time and
get out of alignment. This
attention to detail is a big part of
why the Razr is a premium price.“Going back to the beginning
of the program, we did a lot of
research, and partnered with our
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company] research and
development team, and evaluated
different hinge systems,” says
Steen. “We narrowed it down to
three different types of hinges.
And then we evaluated them
based on reliability, quality, the
ability to provide that consistent
feel of opening and closing.”
Part of that feeling is what
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they knew from the original Razr
that people would want to play
with a satisfying mechanism. In
fact, the whole arc of motion as
you open and close the device
was polished to perfection.“We narrowed it down to a
single hinge, we then had to start
tuning it. The trick is to be able
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be comfortable to be able to
close,” says Steen, adding that
he’s opening and closing his own
Razr as a habit while we speak.
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and closing the device with one
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snapping sound at the end is
where we have some magnets
come in to provide that tight
closure when it’s closed, so that
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“The hinge system, and the
development around that, took
many, many months to tune it,
and to get it just right.”MARCH 2020 T3 47Sponsored