Patents by Inventor Susan Kelpin

Susan Kelpin has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Hydraulic valve assembly with tank return flow compensation
    Patent number: 9476432
    Abstract: An apparatus has a pilot-operated spool valve connecting first and second work passages selectively to a supply conduit and a tank conduit. A first check valve normally allows fluid flow only in one direction from the first work passage to a first workport and when pilot-operated allows bidirectional fluid flow. A second check valve normally allows fluid flow only from the second work passage to a second workport and when pilot-operated allows bidirectional fluid flow. A first pilot valve selectively applies pressure to one end of the spool and to pilot operate the first check valve. A second pilot valve selectively applies pressure to another end of the spool and to pilot operate the second check valve. When fluid drains from a workport to the tank conduit, the associated check valve operates to maintain a predefined pressure in the first or second work passage through which that fluid flows.
    Type: Grant
    Filed: October 4, 2013
    Date of Patent: October 25, 2016
    Assignee: HUSCO International, Inc.
    Inventors: Jason Greenwood, Matthew J. Rades, Susan Kelpin
  • HYDRAULIC VALVE ASSEMBLY WITH TANK RETURN FLOW COMPENSATION
    Publication number: 20150096619
    Abstract: An apparatus has a pilot-operated spool valve connecting first and second work passages selectively to a supply conduit and a tank conduit. A first check valve normally allows fluid flow only in one direction from the first work passage to a first workport and when pilot-operated allows bidirectional fluid flow. A second check valve normally allows fluid flow only from the second work passage to a second workport and when pilot-operated allows bidirectional fluid flow. A first pilot valve selectively applies pressure to one end of the spool and to pilot operate the first check valve. A second pilot valve selectively applies pressure to another end of the spool and to pilot operate the second check valve. When fluid drains from a workport to the tank conduit, the associated check valve operates to maintain a predefined pressure in the first or second work passage through which that fluid flows.
    Type: Application
    Filed: October 4, 2013
    Publication date: April 9, 2015
    Applicant: HUSCO International, Inc.
    Inventors: Jason Greenwood, Matthew J. Rades, Susan Kelpin