Patent ID: 8641671

Claim:
A delivery mechanism of an infusion pump for dispensing fluid to a patient, the delivery mechanism comprising: a spool slidingly disposed in a bore of a delivery mechanism housing; and an o-ring seal disposed on the spool, the o-ring seal comprising: a gland for seating an o-ring including an outer circumferential groove extending circumferentially around a longitudinal axis of a cylindrical body of the spool, the circumferential groove including an angled first surface and an angled second surface opposite the angled first surface and an inner overflow channel disposed below the angled first and second surfaces and including a pair of sidewalls each extending downwardly from and at an angle to one of the angled first and second surfaces and a bottom; and an o-ring disposed in the gland with a first circumferential band of the o-ring resting on the first angled surface and a second circumferential band of the o-ring resting on the second angled surface above the overflow channel with the o-ring in a substantially uncompressed state.