Patents by Inventor Mark R. Bartholomew

Mark R. Bartholomew 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: 7400135
    Abstract: A Printed Circuit Board (PCB) test fixture includes flex sensors for monitoring the flex (or distortion) of the PCB during testing. The PCB is positioned above irregular array of test probes. The test probes are aligned with electrical test points on the PCB. The PCB is then pressed downward against the test probes by an irregular array of pushers. The positions of the pushers are generally specified by a PCB manufacturer to avoid PCB elements and the positions of the test probes are generally specified by the PCB manufacturer to obtain desired signals.
    Type: Grant
    Filed: February 23, 2007
    Date of Patent: July 15, 2008
    Assignee: Quality One Test Fixturing, Inc.
    Inventors: Mark R. Bartholomew, Richard Leonard, Thomas Wohlhieter
  • Patent number: 5311120
    Abstract: An apparatus is provided for testing both the integrity and the functionality of the electrical circuit tracings on a printed circuit board. The apparatus is a bed-of-nails test fixture. The device has a plurality of parallel test probes affixed to the bottom plate of the fixture. The plurality of test probes consists of a plurality of short probe members and a plurality of long probe members. The height of the long probe members is telescopically alterable between the height of the short probe members and the maximum height of the long probe members. The long probe members have an internal spring which tends to maintain the long probe members at their maximum height. The device also has two slide bars disposed on opposite sides of the fixtures. The slide bars have a plurality of key hole shaped apertures.
    Type: Grant
    Filed: January 6, 1993
    Date of Patent: May 10, 1994
    Inventor: Mark R. Bartholomew
  • Patent number: 4091536
    Abstract: A rotary cutting device primarily used for the cutting of vegetation and which includes an outer housing having a motor mounted within the housing. A bobbin assembly which stores a selected amount of a filament permits dispensing of the filament through a hollow drive shaft which is rotated by the motor. The lower end of the filament serves as a rotating cutting element. The bobbin assembly is capable of being shifted axially with respect to the drive shaft in order to dispense a selected amount of the filament when shifted to a lower position and which also prevents locking action of the filament against unauthorized withdrawal when the bobbin assembly is normally biased to its upper position. The rotary cutting device also includes an outwardly flaring lower skirt section which is provided with a recess having a balancing element such as a liquid or semi-liquid material contained therein for balance against both static and dynamic imbalance created by the rotary action.
    Type: Grant
    Filed: January 10, 1977
    Date of Patent: May 30, 1978
    Inventor: Mark R. Bartholomew