Patents by Inventor James C. Alexander

James C. Alexander has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6144951
    Abstract: A method is disclosed for tuning parameter values in a recording channel of a data storage device. The parameter values are tuned using a genetic process based on the principles of simulated evolution. An initial population of individuals is generated wherein each individual includes a value for each of a plurality of channel parameters. Fitness values are then calculated for each of the individuals. Individuals are then chosen for mating from the initial population based on the calculated fitness values. The chosen individuals are manipulated using genetic operators to produce a new population of parameter strings. Fitness values are then calculated for the new population and the cycle is repeated. The process is continued until a desired fitness is achieved or a predetermined number of generations have been produced. After the process has ended, an individual is chosen based on fitness values and the channel parameters of the data storage system are set accordingly.
    Type: Grant
    Filed: July 10, 1998
    Date of Patent: November 7, 2000
    Assignee: Maxtor Corporation
    Inventors: Mark B. Dittmar, James C. Alexander, Martin I. Lynch
  • Patent number: 6139242
    Abstract: A vehicle restraint for preventing movement of a vehicle from a parked position has a frame mountable at a loading dock to position a vehicle restraint mechanism operably coupled to the frame. The vehicle restraint mechanism has a restraining member with at least one hook movable between a lower inoperative position where said restraining member is out of contact with a vehicle to be restrained and an upper operative position where the restraining member contacts said vehicle and prevents movement from a parked position. A source of power, such as an actuator moves the restraining member upward to the operative position by having linkage coupling the source of power to the restraining member. A resilient member is coupled to the linkage and biases the restraining member into engagement with the vehicle.
    Type: Grant
    Filed: April 16, 1997
    Date of Patent: October 31, 2000
    Assignee: United Dominion Industries, Inc.
    Inventor: James C. Alexander
  • Patent number: 6125491
    Abstract: A dock leveler has a deck pivotally mounted to a frame. A counterbalance mechanism uses a pair of pivoting links connected together at a common point with a tension spring that is coupled at the other end to the deck. The links together with the frame and the deck form a four-bar linkage biased by the spring to counterbalance the weight of the deck.
    Type: Grant
    Filed: September 21, 1998
    Date of Patent: October 3, 2000
    Assignee: United Dominion Industries, Inc.
    Inventor: James C. Alexander
  • Patent number: 6123496
    Abstract: A system for restraining a vehicle, such as a truck having a pair of separated tires mounted on an axle, positioned at a loading dock. A member is movable from a stored position near or under the loading dock to an operative position under the vehicle and located between said separated tires. A pair of restraining elements are mounted on the movable member and are movable from a stored position between the tires to an outward extended position where each of the restraining elements engage a respective one of said pair tires. A mechanism, such as an hydraulic system, is mounted to said member at one end and to a fixed point at the other to move the member to a position under the vehicle. The pair of restraining elements is moved to the outward extended position by action of the moving mechanism for the member or by movement of a sensor that contacts a tire.
    Type: Grant
    Filed: August 26, 1997
    Date of Patent: September 26, 2000
    Assignee: United Dominion Ind., Inc.
    Inventor: James C Alexander
  • Patent number: 6082952
    Abstract: An automatic vehicle chock has a chock and a locking mechanism movable on a rail from a retracted position to a position where the chock is extended and held in position by the locking mechanism. A sensor moves with the chock to determine the position of the wheel to be chocked and extend the chock. The position of the sensor relative to the chock can be adjusted. The device also employs mechanical assemblies carried by the carriage assembly to retract the chock without the use of a brake. In one embodiment a cam is used to reverse the direction of the chock arm retaining spring after the chock has been engaged. In a second embodiment the chock is continuously biased to the stored position and a latch is used to hold the chock outward until it is locaked in posiion. The latch is then released and the bias to the stored position is restored so that the chock will retract when the lock is released.
    Type: Grant
    Filed: December 12, 1997
    Date of Patent: July 4, 2000
    Assignee: United Dominion Ind., Inc.
    Inventor: James C. Alexander
  • Patent number: 6062796
    Abstract: A vehicle restraint having a fixed member such as a frame mounted to a dock face and a hook movable relative to the fixed member for engaging a portion of a vehicle and restraining movement of the vehicle away from the dock. A non-contact sensor is employed to determine engagement of the hook with a portion of the vehicle. The sensor is positioned to provide an effective magnetic field in the zone of contact so that engagement with an ICC bar on the vehicle can be ascertained. The sensor may also be a sensor bar pivotally movable respect to a vertical restraining member. The sensor bar houses a sensor that determines relative movement between itself and a target to provide a signal indicative of engagement when the sensor bar is depressed by the vehicle.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: May 16, 2000
    Assignee: United Dominion Ind., Inc.
    Inventor: James C. Alexander
  • Patent number: 6035475
    Abstract: A dockboard, such as a pit type comprising a frame, a deck attached to the frame at one end thereof, a lip hinged to another end of the deck for movement between a pendant position and an outward extended position. A maintenance assembly for the dockboard has a pivotable prop mounted to the underside of the deck for movement between a stored position generally parallel to the deck and a downward extended position supporting the deck. A locking member secures the prop in both the stored and the extended position. The lip may be supported by the maintenance assembly using a spring member to support the lip support bar, or move a member into engagement thereby preventing the lip from falling.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: March 14, 2000
    Assignee: United Dominion Ind., Inc.
    Inventor: James C. Alexander
  • Patent number: 6033174
    Abstract: A vehicle restraint having a fixed member such as a frame mounted to a dock face and a hook movable relative to the fixed member for engaging a portion of a vehicle and restraining movement of the vehicle away from the dock. A non-contact sensor is employed to determine engagement of the hook with a portion of the vehicle. The sensor is positioned to provide an effective magnetic field in the zone of contact so that engagement with an ICC bar on the vehicle can be ascertained.
    Type: Grant
    Filed: August 29, 1997
    Date of Patent: March 7, 2000
    Assignee: United Dominion Ind., Inc.
    Inventor: James C. Alexander
  • Patent number: 6006389
    Abstract: An adjustable bumper system for use at a loading dock which has a dock leveler having a deck pivotally mounted to a portion of the dock. The dock leveler has a lip pivotally attached to one end of said deck. The bumper system has a pair of support members each mounted to a portion of the dock. The support members may be pivotally mounted and extend along sides of the deck of said dock leveler. The support members may also be mounted to the dock face and move vertically. Dock bumpers are mounted to each support member and are positionable between two different vertical positions as the support member is moved. The dock bumpers project outward from the dock beyond the pendent lip and are adjustable to engage the rear of vehicles having different heights.
    Type: Grant
    Filed: October 15, 1998
    Date of Patent: December 28, 1999
    Assignee: United Dominion Ind., Inc.
    Inventor: James C Alexander
  • Patent number: 5934857
    Abstract: A chocking device for securing a vehicle at a loading dock having a guide rail mountable to a driveway and a carriage movable on the guide rail. A drive mechanism, which may be hydraulic or electric is employed to advance the carriage from a stored position to a position proximate to a wheel of the vehicle. A chock assembly is pivotedly mounted on the carriage and is movable by the drive mechanism from a retracted position to an engaging position. The chock assembly comprises an arm having a sensor bar to contact one portion the wheel and a chock plate movable in response to contact of the sensor against the wheel to contact another portion of the wheel and block movement of the vehicle. A lock assembly is mounted on the guide rail for movement thereon, and is moved by the drive mechanism into contact with the chock plate to restrain the chock plate in the extended position.
    Type: Grant
    Filed: November 21, 1996
    Date of Patent: August 10, 1999
    Assignee: United Dominion Ind., Inc
    Inventor: James C Alexander
  • Patent number: 5926890
    Abstract: A dock leveler having a frame, a deck hingedly mounted at on end to the frame and a lip hingedly mounted to the deck at another thereof. The lip has a hinge tube affixed to the lip and a gusset joined to both the lip and the hinge tube. The gusset has an end joining the lip having a width greater than an end joining the hinge tube. The gusset may have a trapezoidal shape and the end of the gusset joining the lip is affixed by two welds each spanning the width of the end joining the hinge tube and disposed between the gusset and the hinge tube. The two welds are joined to each other by extending around edges of the gusset. A single gusset may span the lip and be joined to multiple hinge tubes.
    Type: Grant
    Filed: October 22, 1996
    Date of Patent: July 27, 1999
    Assignee: United Dominion Industries, Inc.
    Inventor: James C. Alexander
  • Patent number: 5881414
    Abstract: An adjustable bumper system for use at a loading dock which has a dock leveler having a deck pivotally mounted to a portion of the dock. The dock leveler has a lip pivotally attached to one end of said deck. The bumper system has a pair of support members each mounted to a portion of the dock. The support members may be pivotally mounted and extend along sides of the deck of said dock leveler. The support members may also be mounted to the dock face and move vertically. Dock bumpers are mounted to each support member and are positionable between two different vertical positions as the support member is moved. The dock bumpers project outward from the dock beyond the pendent lip and are adjustable to engage the rear of vehicles having different heights.
    Type: Grant
    Filed: November 27, 1996
    Date of Patent: March 16, 1999
    Assignee: United Dominion Ind., Inc.
    Inventor: James C. Alexander
  • Patent number: 5832554
    Abstract: A dock leveler, typically powered by an electric actuator or other motive source has a frame and a deck pivotally mounted to the frame. The source of power to move the deck is coupled to the underside of the deck. An extendable lip is pivotally mounted to one end of the deck and an arm assembly is coupled at one end to the lip and at another end to a crank carried by the deck to utilize movement of the deck to raise said lip into an extended position. A cam-latch arm is resiliently coupled to the arm assembly and selectively bearing on the crank by means of a spring coupling to the arm assembly. A linkage is coupled between the frame and said cam-latch arm to urge said cam-latch arm into contact with the crank as the deck is raised. This tends to cause movement between the cam portion and a roller on the crank which in turn provides a component of force to assist in raising said lip into the extended position.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: November 10, 1998
    Assignee: United Dominion Industries, Inc.
    Inventor: James C. Alexander
  • Patent number: 5831540
    Abstract: A system to determine the usage of loading dock equipment such as a dock leveler, a vehicle restraint and a barrier gate to provide an output indicative thereof. For each loading dock component mounted at a loading dock in an operable configuration whose operation is to be monitored, sensor outputs are used to provide data accumulated by PLC's located in a control panel associated with the loading dock. When operation of a piece of equipment is initiated the occurrence delivers an output signal to the PLC. A counting circuit accumulates a count of the output signals. The panel has displays in the form of lights and screens and the data maybe read out by means of a hand held unit for display and/or programing or delivered to a remote PC by appropriate cable.
    Type: Grant
    Filed: July 24, 1995
    Date of Patent: November 3, 1998
    Assignee: United Dominion Ind., Inc.
    Inventors: Vincent Sullivan, James C. Alexander
  • Patent number: 5826291
    Abstract: A dock leveler having a frame adapted to be fixedly mounted at a dock with a deck, pivotally mounted to the frame at one end thereof, and having a pivotable lip at the other end. A spring is mounted to the deck and the frame and supports the deck. An electric actuator is coupled to the deck and moves the deck from a generally horizontal stored position into an operative position. A control circuit is employed for controlling operation of the electrical actuator. A float member couples the actuator to the frame and carries a sensor. A limit switch is responsive to movement of the sensor so that power is terminated to the actuator when the deck reaches either an operative elevated position or a fully lowered position. In the operative elevated position float is provided by having the float member displaced from the frame to allow the electric actuator to move with the deck without being powered to reposition the system.
    Type: Grant
    Filed: October 22, 1996
    Date of Patent: October 27, 1998
    Assignee: United Dominion Industries, Inc.
    Inventor: James C. Alexander
  • Patent number: 5813072
    Abstract: A dock leveler comprises a deck pivotally mounted at one end thereof for movement and having a lip mounted at the other end thereof. A safety leg assembly is pivotally mounted to an underside of said the and is biased into an extended position. A cam structure is carried by the safety leg assembly and pivotal therewith. A spring biases the cam in a direction to maintain the safety legs in the extended position. The cam structure has a slot into which a pin mounted on the safety legs engages. If the deck falls rapidly a surface on the cam engages a member on a stop block. This causes the cam to rapidly move but the spring attached to the pin cannot cause the legs to move as rapidly and it shifts in the slot. This exposes the safety leg supporting surfaces which contact a surface on the stop block to limit travel of the deck.
    Type: Grant
    Filed: November 27, 1996
    Date of Patent: September 29, 1998
    Assignee: United Dominion Ind., Inc.
    Inventor: James C. Alexander
  • Patent number: 5774920
    Abstract: A dock leveler having a frame adapted to be fixedly mounted at a dock with a deck, pivotedly mounted to the frame at one end thereof, and having a pivotable lip at the other end. A spring is mounted to the deck and the frame and supports the deck. An electric actuator is coupled to the deck and the frame and moves the deck from a generally horizontal stored position into an operative position. A control circuit is employed for controlling operation of the electrical actuator. The actuator carries a limit switch which is responsive to movement so that power is terminated to the actuator when the deck reaches either a stored or operative position.
    Type: Grant
    Filed: May 20, 1996
    Date of Patent: July 7, 1998
    Assignee: United Dominion Industries, Inc.
    Inventor: James C. Alexander
  • Patent number: 5743697
    Abstract: A system for restraining a vehicle, such as a truck having a pair of separated tires mounted on an axle, positioned at a loading dock. A member is movable from a stored position near or under the loading dock to an operative position under the vehicle and located between said separated tires. A pair of restraining elements are mounted on the movable member and are movable from a stored position between the tires to an outward extended position where each of the restraining elements engage a respective one of said pair tires. A mechanism, such as an hydraulic system, is mounted to said member at one end and to a fixed point at the other to move the member to a position under the vehicle. The pair of restraining elements is moved to the outward extended position by action of the moving mechanism for the member or by movement of a sensor that contacts a tire.
    Type: Grant
    Filed: July 11, 1996
    Date of Patent: April 28, 1998
    Assignee: United Dominion Ind., Inc.
    Inventor: James C. Alexander
  • Patent number: 5709518
    Abstract: A chocking device for securing a vehicle at a loading dock having a guide rail mountable to a driveway and a carriage movable on the guide rail. A drive mechanism, which may be hydraulic or electric is employed to advance said carriage from a stored position to a position proximate to a wheel of the vehicle. A chock assembly is pivotedly mounted on the carriage and is movable by the drive mechanism from a retracted position to an engaging position. In one embodiment the chock assembly comprises an arm having a sensor bar to contact one portion of the wheel and a chock plate movable in response to contact of the sensor bar against the wheel to contact another portion of the wheel and block movement of the vehicle. A lock assembly is mounted on the guide rail for movement thereon, and is moved by the drive mechanism into contact with the chock plate to restrain the chock plate in the extended position.
    Type: Grant
    Filed: November 27, 1995
    Date of Patent: January 20, 1998
    Assignee: United Dominion Industries
    Inventors: James C. Alexander, Robert C. Hersey
  • Patent number: 5586355
    Abstract: A vertically storing dock leveler comprises a deck, a pivot coupling the leveler to the mounting pit to allow the deck the rotate from a stored vertical position to an operative horizontal position and a source of power to rotate the deck. A sensor is mounted to the underside of the deck for delivering an output that ceases downward movement of said deck when a foreign object such as a human is sensed under said deck. The sensor comprises a wire mounted to span said deck at a position below it and a switch responsive to movement of said wire. The switch may be a mechanical, proximity or photoelectric type. The wire is fixed at one side of said deck and coupled to a pivoting member at the other side with the pivoting member normally positioned in proximity to said switch. A spring is employed to bias the pivoting member to a centered position relative to the switch in opposition to tension of the wire.
    Type: Grant
    Filed: March 21, 1995
    Date of Patent: December 24, 1996
    Assignee: United Dominion Industries, Inc.
    Inventors: Donald Metz, James C. Alexander