Patents Assigned to Northfield Metal Products Ltd.
  • Patent number: 6378943
    Abstract: A chair seat tilt lock mechanism has a detent to latch an actuating lever in a locked and unlocked position. When the lever is moved to a locking position, a spring urges a moveable locking member toward a locking position, however, the moveable locking member only moves to its locking position when the chair is tilted to properly register the moveable locking member with a fixed locking member. When the lever is moved to an unlocking position, another spring urges the moveable locking member to an unlocking position. The moveable locking member may be a slider which slides under a fixed abutment to lock the chair from tilting. Alternatively, the moveable locking member may be a pivoting arm with a series of openings which may receive the forked end of a tongue in a locked position.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: April 30, 2002
    Assignee: Northfield Metal Products Ltd.
    Inventors: Ken A. Beggs, Gerard J. Matern
  • Patent number: 6045187
    Abstract: A chair height adjustment mechanism which can be retrofit to a chair comprises a rod with a circumferential notch proximate one end for insertion through openings in the chair seat support bracket above a valve opening member of the chair height adjustment cylinder such that the rod is free to tilt against the valve opening member. The circumferential notch receives the looped end of the inner wire of a co-axial cable. The sheath of the cable is supported by a flange of a support member. The support member has an opening which receives the adjustment cylinder and a wheel which redirects the inner wire from the rod toward the flange. The other end of the co-axial cable terminates in a user actuator which may be mounted to the underside of the chair seat.
    Type: Grant
    Filed: May 8, 1998
    Date of Patent: April 4, 2000
    Assignee: Northfield Metal Products Ltd.
    Inventor: William S. Stumpf
  • Patent number: 5997087
    Abstract: A chair seat tilt lock comprises a slider riding along a track on the seat and an abutment extending from chair seat post. The slider is spring biased into registration with the abutment to block the chair against tilting and may also be moved away from the abutment so that the chair is then free to tilt. The slider is mover by a lever arm connected to the slider by a co-axial cable with an enlargement at the end of the inner cable which allows the cable to be releasably press fit into a skeleton key-shaped passageway through the slider.
    Type: Grant
    Filed: August 28, 1998
    Date of Patent: December 7, 1999
    Assignee: Northfield Metal Products Ltd.
    Inventor: William S. Stumpf
  • Patent number: 5944387
    Abstract: A chair armrest bar is horizontally slidably received in a channel of a base attached to a chair seat. The base defines longitudinally arranged interconnected slots in its bottom wall. A locking lever is pivotably mounted to the armrest bar. The lever has a locking pin which is biased into one of the slots to lock the armrest in position; the lever may be tilted to an unlocking position to allow the bar to slide. The lever is releasably attached to the bar by a mount so that the lever may be removed to allow replacement of the bar.
    Type: Grant
    Filed: May 4, 1998
    Date of Patent: August 31, 1999
    Assignee: Northfield Metal Products Ltd.
    Inventor: William S. Stumpf
  • Patent number: 5649741
    Abstract: An adjusting mechanism for adjusting the position of a first structural member relative to a second structural member. The mechanism is particularly well suited for use as a mechanism for adjusting the vertical or lateral position of a chair back or armrest relative to a chair seat and is adapted for one-handed adjustment. The adjustment mechanism has an arm mountable to a first structural member and slider securable to a second structural member that slidably engages the arm. A ratchet rack is on the arm and a pawl is supported by the slider, which is adapted to engage the ratchet rack, permitting only one direction movement of the slider along the arm. One of the pawl and slider has a cam guide, which has a portion substantially transverse to the ratchet rack and a portion extending from the substantially transverse portion in a direction substantially parallel to the rack. The other of the slider and the pawl has a cam follower extending therefrom. The cam follower, slidably engages the cam guide.
    Type: Grant
    Filed: February 16, 1996
    Date of Patent: July 22, 1997
    Assignee: Northfield Metal Products Ltd.
    Inventor: Ken A. Beggs
  • Patent number: D397889
    Type: Grant
    Filed: July 16, 1997
    Date of Patent: September 8, 1998
    Assignee: Northfield Metal Products Ltd.
    Inventor: William S. Stumpf
  • Patent number: D407246
    Type: Grant
    Filed: January 13, 1998
    Date of Patent: March 30, 1999
    Assignee: Northfield Metal Products Ltd.
    Inventor: William S. Stumpf
  • Patent number: D411396
    Type: Grant
    Filed: January 13, 1998
    Date of Patent: June 22, 1999
    Assignee: Northfield Metal Products Ltd.
    Inventor: William S. Stumpf
  • Patent number: D411929
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: July 13, 1999
    Assignee: Northfield Metal Products Ltd.
    Inventor: William S. Stumpf