David R. Friswell

Person

  • Holliston, MA, US

Patents Grantslast 30 patents

  • Information Patent Grant

    Diaphragm valve

    • Patent number 4,070,004
    • Issue date Jan 24, 1978
    • Waters Associates, Inc.
    • David R. Friswell
    • F16 - ENGINEERING ELEMENTS AND UNITS GENERAL MEASURES FOR PRODUCING AND MAINT...