said arch block having a curved back side and a toothed front side and being biased by said first end of {HEAD ~ said spring} into engagement with said ratchet wheel in a radial direction relative to said wall for limiting rotary motion of said ratchet wheel within said chamber to one direction; said arch block having a predetermined transverse width dimension, and {TAIL ~ a height} of teeth on said toothed front side of said arch block being approximately equal to a height of said ratchet teeth on said ratchet wheel 
said arch block having a curved back side and a toothed front side and being biased by said first end of { HEAD ~ said spring } into engagement with said ratchet wheel in a radial direction relative to said wall for limiting rotary motion of said ratchet wheel within said chamber to one direction ; said arch block having a predetermined transverse width dimension , and { TAIL ~ a height } of teeth on said toothed front side of said arch block being approximately equal to a height of said ratchet teeth on said ratchet wheel
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH