Main Page | Report this Page
 
   
Science Forum Index  »  Mechanics Forum  »  dynamic tension measurement?
Page 1 of 1    
Author Message
Trs80
Posted: Wed Apr 16, 2008 11:51 pm
Guest
I want to measure dynamic thread tension on an industrial sewing machine
without affecting the thread tension.

Is there a strain or tension gauge that can act as a spring as well? The
notion being to replace a tension spring on the machine with the gauge,
adjust the gauge spring for proper thread tension and then the gauge could
provide dynamic tension readings as the machine operates.

Any thoughts appreciated!
Mechanical Magic
Posted: Thu Apr 17, 2008 6:15 am
Guest
On Apr 16, 8:51 pm, "Trs80" <tr...@yahoo.com> wrote:
Quote:
I want to measure dynamic thread tension on an industrial sewing machine
without affecting the thread tension.

Is there a strain or tension gauge that can act as a spring as well? The
notion being to replace a tension spring on the machine with the gauge,
adjust the gauge spring for proper thread tension and then the gauge could
provide dynamic tension readings as the machine operates.

Any thoughts appreciated!

Yes, a spring can be fitted with a strain gauge to measure thread
tension.
But, it's very difficult to do, and fragile.
Can the SPRING MOUNT be instrumented?
Given the rate of change, the spring mass probably won't affect the
measurement.

Check your email, this is best discussed with pictures.

Dave
N:dlzc D:aol T:com (dlzc)
Posted: Thu Apr 17, 2008 7:59 am
Guest
Dear Trs80:

"Trs80" <trs80@yahoo.com> wrote in message
news:HHANj.12315$CO2.11224@newsfe12.phx...
Quote:
I want to measure dynamic thread tension on
an industrial sewing machine without affecting
the thread tension.
....
Any thoughts appreciated!

Just a couple...
1) replace / support what holds / tensions the spring with a
standard force gauge
2) analyze the oscillations of the thread optically. It will
have one component that is a function of machine cycle frequency,
and another that is its natural frequency (comprised of
mass-per-unit-length and tension).

David A. Smith
Trs80
Posted: Thu Apr 17, 2008 11:38 pm
Guest
thx. my email is xxxwayne86@cox.net
remove the xxx.
thank you
"Mechanical Magic" <google@mechanicalmagic.com> wrote in message
news:a2e5e1fc-4c64-43ea-bbf8-f041e5b61ae4@d1g2000hsg.googlegroups.com...
Quote:
On Apr 16, 8:51 pm, "Trs80" <tr...@yahoo.com> wrote:
I want to measure dynamic thread tension on an industrial sewing machine
without affecting the thread tension.

Is there a strain or tension gauge that can act as a spring as well? The
notion being to replace a tension spring on the machine with the gauge,
adjust the gauge spring for proper thread tension and then the gauge
could
provide dynamic tension readings as the machine operates.

Any thoughts appreciated!

Yes, a spring can be fitted with a strain gauge to measure thread
tension.
But, it's very difficult to do, and fragile.
Can the SPRING MOUNT be instrumented?
Given the rate of change, the spring mass probably won't affect the
measurement.

Check your email, this is best discussed with pictures.

Dave
Mechanical Magic
Posted: Fri Apr 18, 2008 8:02 am
Guest
On Apr 17, 8:38 pm, "Trs80" <tr...@yahoo.com> wrote:
Quote:
thx. my email is xxxwayn...@cox.net
remove the xxx.


I tried another email, using the group main thing.
You can get to me using
google
@
mechanicalmagic.com

(if you put it back together. and the board leaves it alone)

I've done some measurements of strain at 40kHz data rates, down to
static load.
Instrumenting the machine is the easy part, data gathering may be an
issue.
Dave
 
Page 1 of 1       All times are GMT - 5 Hours
The time now is Sat Sep 06, 2008 10:30 pm