Clutch Lock Disengaging

Clutch Lock Disengaging

Jeff Green

7/9/2003

To Whom It May Concern:

At SPS we make a lock that is similar to the IRS-500 series locks, the
SPS-500's. We use the same one-way roller clutch bearing technology as
Cascade and have experienced the same problem in the past. SPS has
redesigned our locks to include a secondary locking mechanism. To explain
how a one-way roller clutch bearing works I have put together a technical
flier on our SPS 500 series locks. You should see it soon in your next
shipment from SPS or if you would like me to e-mail it to you directly reply
to this e-mail. Below is the text from the SPS Clutch Lock flier; it is
easier to understand with the graphics from the flier.

Traditional One-Way Roller
Clutch and Bearing, How It Works:
Rollers wedge between shaft
and outer race. Positive wedging forces
prevent slipping. In laboratory pull test, the
SPS Clutch Lock is capable of holding loads
greater than100 lbs. Laboratory testing has also
found that in unique situations when a one-way
roller clutch is under slight pressure, such as a
patient sitting, the rollers can release from the
shaft and allow it to turn in reverse. This problem
was present in all locks using one-way roller
clutch technology, SPS redesigned the 500 series
locks to incorporate a secondary locking
mechanism, the spring loaded pawl.
The New - Spring Loaded Pawl:
Added as a secondary locking mechanism to
ensure patient safety.
Bonus: The new spring loaded pawl emits
an audible click to alert patients of donning.



I hope you find this information helpful.
Best regards,

Jeff Green, RTPO
~Manager of Technical Services/Training~
SPS, Southern Prosthetic Supply
Tel: 800-767-7776 ext.141
Fax: 678-455-8884
<Email Address Redacted> <mailto:<Email Address Redacted>>
www.spsco.com < <URL Redacted>>