Patents Assigned to Stromag, Inc.
  • Patent number: 6543587
    Abstract: A vehicle brake assembly has a rotor that mounts to a shaft of the vehicle for rotation with it. The rotor has an annular braking surface. A hydraulic piston is non-rotatably mounted to the vehicle. The piston is movable axially relative to the rotor and has a braking surface for frictional engagement with the braking surface of the rotor when hydraulic fluid pressure is supplied to the piston. A coil body having an electromagnetic coil is axially movable relative to the rotor. A coil plate is mounted adjacent the coil body and is attracted to the coil body when electrical power is supplied to the coil. A coil spring is mounted between the coil plate and the coil body. The coil spring moves the coil plate away from the coil body causing braking action when the electrical power is removed from the coil.
    Type: Grant
    Filed: September 17, 2001
    Date of Patent: April 8, 2003
    Assignee: Stromag, Inc.
    Inventor: James W. Albrecht
  • Patent number: 6211590
    Abstract: A braking system has a shaft which rotates with a wheel on a vehicle. A rotor rotates with the shaft within a housing. The housing also contains an electromagnetic coil and two armatures. The rearward armature is in contact with the coil while the forward armature is adjacent to the rotor. The rearward armature does not touch the rotor and is more strongly attracted to the coil than the forward armature. Each armature has springs which independently urge it toward the rotor. An electric circuit causes the current supplied to the coil to gradually decay rather than abruptly stop. When the vehicle is parked and subjected to static braking, the coil is de-energized so that the armatures are forced toward the rotor by their springs. In this state, the rearward armature applies force to the forward armature to increase the pressure against the rotor. When the system is disengaged, the coil is energized to attract the armatures and allow the rotor to freely rotate.
    Type: Grant
    Filed: October 1, 1998
    Date of Patent: April 3, 2001
    Assignees: Stromag, Inc., Raymond Corporation
    Inventors: James W. Albrecht, Ming Liang Fe
  • Patent number: 5699883
    Abstract: A variable electric brake assembly applies braking force to the wheel of a materials handling vehicle through a rotor shaft. A brake rotor rotates on the rotor shaft and is located within the brake assembly. When the vehicle is in a parked position, both an inner coil and an outer coil are de-energized. With the inner coil de-energized, an inner armature is not attracted to the inner coil, and the inner armature is forced against the brake rotor by springs to prevent the rotation of the brake rotor. When the vehicle is moving in a free running position, the outer coil remains de-energized while the inner coil is energized. With the inner coil energized, the inner armature is attracted to the inner coil and overcomes the force of the springs, thereby allowing the brake rotor to freely rotate. When the vehicle undergoes dynamic braking, both the outer coil and the inner coil are energized.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: December 23, 1997
    Assignee: Stromag, Inc.
    Inventor: James W. Albrecht
  • Patent number: 4400638
    Abstract: A shaft mounted eddy current variable speed drive or clutch has a hub which is adapted to be mounted on the shaft of a prime mover, such as an electric motor, and drives an armature. The hub includes an annular armature. A driven magnetic body is mounted for rotation on the hub and includes an array of poles magnetically associated with the armature through a working air grap and are energized from an electric coil mounted on the magnetic body. A slip ring assembly is also mounted on the magnetic body as well as an output pulley through which power is taken from the body. A non-rotating brush holder assembly, as well as a magnetic speed pick-up are mounted on a support bracket which bracket is, in turn, piloted to and mounted on the hub through a bearing. A torque arm prevents the rotation of the brush assembly and magnetic pick-up.
    Type: Grant
    Filed: August 20, 1981
    Date of Patent: August 23, 1983
    Assignee: Stromag, Inc.
    Inventors: James W. Albrecht, Harold G. Spriggs