Assertion: valve's spring | /r/CapableOf | aid in spiral rotation
Facets:
value: on said piston valve
type: LOCATION
Source sentences:
text: 12, In a piston valve structure, the com bination of a cylinder with suitable connections for direct air delivery and with a diversion loop tube connected thereto, a spirally rotatable piston valve with suitable air passages and ports cooperating with the said cylinder, and an inverted conical spiral spring connected to react longitudinally and torsionally to aid in the spiral rotation on said piston valve.