Patents Assigned to PT Tech, Inc
  • Patent number: 8066619
    Abstract: A clutch control system is interposed between an engine and a piece of driven equipment. The clutch control system includes a clutch assembly with input and output speed sensors for providing signals corresponding to the shaft rotational speeds of the engine and the driven equipment, respectively. A pressure sensor is connected to the clutch assembly and provides an output signal corresponding to clutch pressure. A temperature sensor is also associated with the clutch assembly and provides a temperature signal corresponding to the operating temperature of the clutch assembly. Transducers of various types are also employed to sense operating conditions such as shock loads or the like. Also included is a machine control system connected to the driven equipment and an engine control module connected to the engine, both of which are interconnected through an SAE J1939 CAN to the clutch control unit.
    Type: Grant
    Filed: April 19, 2008
    Date of Patent: November 29, 2011
    Assignee: PT Tech, Inc
    Inventors: Robert E. Herchick, David C. Heidenrcich, Erik L. Olson, Joseph W. Guinter, David A. Peterman, Arthur F. Gouker, Timothy A. Clapp
  • Patent number: 7493992
    Abstract: A gearbox having an integral wet brake assembly is provided to replace the prior gearbox assembly of an underground mining machine. The brake housing is configured and contoured to be nestingly received upon the gearbox housing and without intrusion upon the output drive flanges. The brake housing includes concentric parking and service brake pistons adapted to engage and disengage a brake disc stack provided within a cavity machined into an end plate of the gear box assembly. An intermediate shaft of the gearbox is provided with a hub to engage the rotary discs of the brake disc stack. The parking brake is normally engaged by a spring and released by hydraulic pressure, while the service brake is normally released by a spring and engaged by hydraulic pressure.
    Type: Grant
    Filed: August 15, 2005
    Date of Patent: February 24, 2009
    Assignee: PT Tech., Inc.
    Inventor: Ralph F. Rogers
  • Patent number: 7472739
    Abstract: Shade structures include awning fabrics carried by awning rolls from which they may be extended to provide shade to areas, and into which they may be retracted when shade is not needed. Closed systems are disclosed in which one or more awning fabrics can be extended through a single drive system. In particular embodiments, the shade structures cover large surface areas and include solar cells for the generation of photovoltaic power.
    Type: Grant
    Filed: October 29, 2004
    Date of Patent: January 6, 2009
    Assignee: PT Tech, Inc
    Inventor: David C. Heidenreich