Patents Assigned to Boulder 12 Investments
  • Patent number: 5123513
    Abstract: A clutch assembly for automotive vehicle four-wheel drives either in association with an axle disconnect or wheel hub incorporates a power shift mechanism which can be remotely activated either when the vehicle is static, in motion and during either forward or reverse direction of movement to positively drive the clutch members into and out of engagement with one another. The power shift mechanism includes sealed envelopes in the form of expandable and contractable compartments which in response to a remote control valve will positively shift the clutch members into and out of engagement, and the members will remain in the shifted position without the continued application of force until positively shifted away from that position by the power shift mechanism. In the alternative, a spool-like shifter may be utilized with positive locking elements which will lock the clutch members in the engaged and disengaged position at the end of travel of the shift mechanism.
    Type: Grant
    Filed: January 15, 1991
    Date of Patent: June 23, 1992
    Assignee: Boulder 12 Investments
    Inventor: Harry A. Petrak
  • Patent number: 5044479
    Abstract: A clutch assembly for automotive vehicle four-wheel drives either in association with an axle disconnect or wheel hub incorporates a power shift mechanism which can be remotely activated either when the vehicle is static, in motion and during either forward or reverse direction of movement to positively drive the clutch members into and out of engagement with one another. The power shift mechanism includes sealed envelopes in the form of expandable and contractable compartments which in response to a remote control valve will positively shift the clutch members into and out of engagement, and the members will remain in the shifted position without the continued application of force until positively shifted away from that position by the power shift mechanism.
    Type: Grant
    Filed: March 12, 1990
    Date of Patent: September 3, 1991
    Assignee: Boulder 12 Investments
    Inventor: Harry A. Petrak
  • Patent number: 4694943
    Abstract: Conversion of a vehicle between two-wheel drive and four-wheel drive is effected by means of a camming assembly and a shift mechanism to temporarily lock the camming assembly against rotation in advancing a drive gear into driving engagement with a receiving gear in converting to four-wheel drive, or to re-engage the camming assembly under the control of the shift mechanism as a preliminary to disengaging the drive gear from the receiving gear in converting to two-wheel drive.
    Type: Grant
    Filed: January 21, 1986
    Date of Patent: September 22, 1987
    Assignee: Boulder 12 Investments
    Inventor: Harry A. Petrak
  • Patent number: 4396098
    Abstract: A fluid vibration damper, such as, a shock absorber includes a cylinder and piston combination in which the piston head travels through a fluid-filled cylinder and has fluid bypass openings in its external surface forming one or more recesses of predetermined cross-sectional configurations and sizes whereby to regulate fluid flow past the piston head according to a performance curve. The bypass openings can be formed in interchangeable elements so as to permit selective variations in the fluid flow characteristics of each particular size or design of shock absorber according to a specific force performance curve.
    Type: Grant
    Filed: February 3, 1981
    Date of Patent: August 2, 1983
    Assignee: Boulder 12 Investments
    Inventor: Harry A. Petrak