Patents Assigned to The Hartfiel Company
  • Patent number: 7831352
    Abstract: A system for controlling motion of a hydraulic actuator during a portion of its range of motion is described, including a sensor on the hydraulic actuator for providing a signal indicating that the actuator is near a portion of its range of motion, and a pneumatic control valve that is configured to selectively modify a pressurized air control signal to in turn restrict flow of pressurized hydraulic fluid to the hydraulic actuator. The hydraulic actuator control system further includes an electronic controller for controlling the pneumatic control valve in response to a signal from the sensor. The hydraulic actuator control system thereby slows the motion of the hydraulic actuator near the portion of its range of motion.
    Type: Grant
    Filed: March 14, 2008
    Date of Patent: November 9, 2010
    Assignee: The Hartfiel Company
    Inventors: Steve P. Laumer, Gary Lee Lagro
  • Publication number: 20090025378
    Abstract: A system for controlling motion of a hydraulic actuator on a refuse collection vehicle. The system includes an operator input device configured to produce a proportional electrical signal that is proportional to the degree of motion of the operator input device. The system further includes a proportional pneumatic control valve that is configured to produce a pressurized air control signal in proportion to the proportional electrical signal, and a hydraulic control valve that is configured to selectively control flow of hydraulic fluid to a hydraulic actuator in response to the pressurized air control signal.
    Type: Application
    Filed: July 25, 2008
    Publication date: January 29, 2009
    Applicant: The Hartfiel Company
    Inventors: Stephen P. Laumer, Gary Lee Lagro
  • Publication number: 20080228323
    Abstract: A system for controlling motion of a hydraulic actuator during a portion of its range of motion is described, including a sensor on the hydraulic actuator for providing a signal indicating that the actuator is near a portion of its range of motion, and a pneumatic control valve that is configured to selectively modify a pressurized air control signal to in turn restrict flow of pressurized hydraulic fluid to the hydraulic actuator. The hydraulic actuator control system further includes an electronic controller for controlling the pneumatic control valve in response to a signal from the sensor. The hydraulic actuator control system thereby slows the motion of the hydraulic actuator near the portion of its range of motion.
    Type: Application
    Filed: March 14, 2008
    Publication date: September 18, 2008
    Applicant: THE HARTFIEL COMPANY
    Inventors: Steve P. Laumer, Gary Lee Lagro
  • Patent number: 6749173
    Abstract: A valve arrangement that controls fluid flow of a working fluid in a fluid system. The valve arrangement including a valve body having first, second, and third pressure chambers functioning under pressure of an operating fluid. The operating fluid is independent of the working fluid. The valve arrangement further including a solenoid valve arranged with the valve body to operably provide fluid communication between the first pressure chamber and the second and third pressure chambers.
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: June 15, 2004
    Assignee: The Hartfiel Company
    Inventor: Daniel Heiling