Patents Represented by Attorney Carl E. Knochelmann, Jr.
  • Patent number: 5974596
    Abstract: An improved hand operated plunger for clearing drains and other plumbing fixtures of obstructions is disclosed. The hand operated plunger has two coaxial handles that help maintain a seal with the plumbing fixture during operation and check valves that direct hydraulic or pneumatic pressure to the obstruction through the application of hand force applied to the movable handle. In the event that one stroke of the handle does not dislodge the obstruction, a second or subsequent stroke may be applied without loosing all of the pressure developed from the first stroke. In one preferred embodiment, air is used to create pneumatic pressure that is applied to the obstruction through check valves and the pressure is increased by subsequent strokes of the movable plunger handle. In an alternate embodiment, liquid, such as water, is used to create hydraulic pressure that is applied to the obstruction through check valves and the pressure developed is directly related to the force applied to the movable plunger handle.
    Type: Grant
    Filed: November 5, 1997
    Date of Patent: November 2, 1999
    Inventor: Michael Jerome Strzok
  • Patent number: D417376
    Type: Grant
    Filed: September 22, 1998
    Date of Patent: December 7, 1999
    Assignee: Havel's Inc.
    Inventor: Howard A. Schmithorst
  • Patent number: D423894
    Type: Grant
    Filed: September 22, 1998
    Date of Patent: May 2, 2000
    Assignee: Havel's Inc.
    Inventor: Howard A. Schmithorst
  • Patent number: D427037
    Type: Grant
    Filed: September 22, 1998
    Date of Patent: June 27, 2000
    Assignee: Havel's Inc.
    Inventor: Howard A. Schmithorst