Patents Assigned to Hoff Engineering Company, Inc.
  • Patent number: 8486263
    Abstract: An improved filter arrangement solves problems associated with dislodging the filter from a support basket at change-out when intimate contact between the filter and basket is no longer desirable. An elastomeric end cap is bonded to the distal end of the filtering medium. The end cap has a circular, outer perimeter defining a diameter less than the inner diameter of the filter basket. The end cap is dome shaped, such that when the filtering element is inserted into the filter basket with the end cap positioned adjacent the bottom of the filter basket, the end cap assumes a pressurized state when a fluid entering the filtering element applies pressure to the end cap, causing the outer perimeter of the end cap to expand radially outwardly, and a non-pressurized state wherein the outer perimeter of the end cap contracts, facilitating an easier removal of the element from the basket.
    Type: Grant
    Filed: July 8, 2010
    Date of Patent: July 16, 2013
    Assignee: Hoff Engineering Company, Inc.
    Inventors: Daniel E. Argue, E. Michael Doyle, Edward M. Doyle
  • Publication number: 20120006734
    Abstract: An improved filter arrangement solves problems associated with dislodging the filter from a support basket at change-out when intimate contact between the filter and basket is no longer desirable. An elastomeric end cap is bonded to the distal end of the filtering medium. The end cap has a circular, outer perimeter defining a diameter less than the inner diameter of the filter basket. The end cap is dome shaped, such that when the filtering element is inserted into the filter basket with the end cap positioned adjacent the bottom of the filter basket, the end cap assumes a pressurized state when a fluid entering the filtering element applies pressure to the end cap, causing the outer perimeter of the end cap to expand radially outwardly, and a non-pressurized state wherein the outer perimeter of the end cap contracts, facilitating an easier removal of the element from the basket.
    Type: Application
    Filed: July 8, 2010
    Publication date: January 12, 2012
    Applicant: Hoff Engineering Company, Inc.
    Inventors: Daniel E. Argue, E. Michael Doyle, Edward M. Doyle
  • Patent number: 7670488
    Abstract: A reliable, cost effective system and method are disclosed for exchanging fluid-filtration filters associated with electrical discharge machines (EDMs) and other applications. The basic system comprises a housing to receive the filter, the housing having a top that opens and a bottom cap with an interior inlet fitting coupled to a supply line carrying fluid to be filtered. A pair of opposing swing arms, each having one end pivotally connected to a filter cabinet or other suitable base and another end pivotally connected to an opposing side of the housing, facilitate a first state, wherein the housing and filter are vertically oriented with the bottom opening of the filter sealed against the fitting for filtering operation, and a second state, wherein the housing is pivoted such that the top is oriented downwardly allowing the filter to disengage from the fitting and slide out of the housing.
    Type: Grant
    Filed: July 14, 2006
    Date of Patent: March 2, 2010
    Assignee: Hoff Engineering Company, Inc.
    Inventors: Edward M. Doyle, E. Michael Doyle, Daniel E Argue