Patents by Inventor David I. McDonald

David I. McDonald 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: 5102177
    Abstract: An article gripper has two cantilevered jaws biased together by a spring assembly to hold an article between arcuate surfaces of the jaws. The jaws are cantilever-mounted from respective pivot pins, and the article enters radially through an opening formed between the outboard ends of the cantilevered jaws. Between the pivot pins and the gripped article, the jaws have interengaging teeth which permit ease of engagement and disengagement as the jaws are pivoted, yet the teeth prevent unwanted sliding movement of one jaw past the other, as an article is located within the jaws.
    Type: Grant
    Filed: August 26, 1991
    Date of Patent: April 7, 1992
    Assignee: Cincinnati Milacron Inc.
    Inventors: Robert C. Dreisig, Raymond L. Hallbach, David I. McDonald
  • Patent number: 4858980
    Abstract: An article gripper with a fixed jaw has a movable jaw mounted on reed springs. Deflection of the movable jaw permits the article to enter and exit the gripper. The movable jaw has an inlet cam surface and an outlet cam surface, configured so that a low-level inlet force deflects the jaw and reeds laterally, while a higher-level outlet, or removal, force is directed parallel to the reed springs causing the jaw to behave stiffly and thus resist pullout of the article.
    Type: Grant
    Filed: August 23, 1988
    Date of Patent: August 22, 1989
    Assignee: Cincinnati Milacron Inc.
    Inventors: Robert C. Dreisig, David I. McDonald
  • Patent number: 4635788
    Abstract: An endless belt type of conveyor for small flat workpieces (chips) provides a series of pockets on a perforate belt, each pocket adapted to support a chip during conveyance through a zone wherein high velocity air jets are directed against the chip. The pockets are formed by facing pairs of series of "H" or "I" shaped crossbars connected between a spaced-apart pair of roller chains. The perforate belt is formed by a Teflon (polytetraflouroethylene) coated fiberglass screen (alternatively silicon rubber) supported by the H crossbars. This construction permits the pockets to move readily around the sprockets about which the roller chains are wound.
    Type: Grant
    Filed: July 12, 1984
    Date of Patent: January 13, 1987
    Assignee: Cincinnati Milacron Inc.
    Inventor: David I. McDonald
  • Patent number: 4580209
    Abstract: A method and apparatus for absolute position measurement for numerically controlled machines is provided. The invention produces a unique measurement signal for all locations within the range of a movable machine member using two measuring devices. Each measuring device produces a unique measurement signal within a portion of the range of motion that cyclically repeats over the entire range of motion. The measuring devices are so arranged that the measurement signal of one completes no more than one more cycle over the range of motion than the measurement signal of the other. The difference between the two measurement signals is unique for all locations and is used to produce an absolute position signal.
    Type: Grant
    Filed: February 6, 1984
    Date of Patent: April 1, 1986
    Assignee: Cincinnati Milacron Inc.
    Inventors: Richard E. Hohn, David I. McDonald, Harold D. Wiebe
  • Patent number: 4520575
    Abstract: An impingement oven wherein a carrier-type conveyor passes between hot air plenums located above and below the conveyor. Horizontally adjacent plenums have their fans located in an off-set position to overhang the other one of the pair. Each plenum has a nozzle plate to direct heated air toward the conveyor so that the air flow is substantially perpendicular to the conveyor and such workpiece(s) as may be thereon. An oven module having four sets of plenums and four conveyors in the same enclosure is described. A plurality of such modules serially arranged provide a multizone oven. The oven is especially suited to heating flat workpieces of thermoplastic resin which are to be processed elsewhere into hollow objects such as containers.
    Type: Grant
    Filed: November 25, 1983
    Date of Patent: June 4, 1985
    Assignee: Cincinnati Milacron Inc.
    Inventors: Donald P. Holmes, David I. McDonald
  • Patent number: 4183979
    Abstract: A method and apparatus are disclosed for precision placement of a workpiece onto a transport member. A plurality of workpieces are aligned in a predetermined spacial relationship upon an infeed conveyor. The workpieces are then moved transversely off the conveyor and dropped through a pair of counter-rotating lubricating rollers. An arcuate chute directs the workpieces from the lubricating rollers to a horizontally disposed planar surface where they are realigned by a cooperating scraper positioned intimately above. Relative movement between the scraper and the planar surface causes to workpieces to be discharged from the surface and precisely deposited upon the transport member.
    Type: Grant
    Filed: May 12, 1978
    Date of Patent: January 15, 1980
    Assignee: Cincinnati Milacron Inc.
    Inventors: Arnold L. Kellermann, David I. McDonald, Robert J. Grone
  • Patent number: 4164391
    Abstract: A conveyor apparatus for carrying workpieces on flat trays has two parallel chains with tray supports connected at equal intervals between the two chains. Each tray support has a clamping device for clamping and releasing flat silicone rubber covered trays against itself. Cams are located between the chains to operate the clamping device to release the tray (for travel through a separate path) at one point in travel and later (when the tray returns from its separate path) to clamp it again. The conveyor is shown as combined with up-and-down elevator means in an oven to give a boustrophedontic path to a plurality of workpieces being heated on trays in the oven: the trays are released and clamped at the entrance to and exit from the oven to allow movement of the trays by the elevators through up and down paths at the release and clamping stations.
    Type: Grant
    Filed: March 17, 1978
    Date of Patent: August 14, 1979
    Assignee: Cincinnati Milacron Inc.
    Inventors: Walter D. Howard, David I. McDonald
  • Patent number: 4133625
    Abstract: A machine for automatically forging and thermoforming of hollow thermoplastic biaxially oriented articles has a carrier assembly to carry, lock and unlock forging dies, indexing means to move the carrier assembly and dies past a series of work stations, and an article unloading means. Three work stations are in the automatic machine: forging where the die parts are locked together and the workpiece is forged into engagement with the die; thermoforming to which the die with the workpiece (now called a preform) gripped therein is moved into register with thermoforming mold means; and article ejecting means which include mechanical means for unlocking the die and removing the hollow article therefrom. The carrier assembly is so supported that the strains of forging and thermoforming are taken up by frame tie rods rather than the die mounting means.
    Type: Grant
    Filed: August 2, 1977
    Date of Patent: January 9, 1979
    Assignee: Cincinnati Milacron Inc.
    Inventors: Arnold L. Kellermann, David I. McDonald
  • Patent number: 4104984
    Abstract: A method and apparatus are disclosed for precision placement of a workpiece onto a transport member. A plurality of workpieces are aligned in a predetermined spacial relationship upon an infeed conveyor. The workpieces are then moved transversely off the conveyor and dropped through a pair of counter-rotating lubricating rollers. An arcuate chute directs the workpieces from the lubricating rollers to a horizontally disposed planar surface where they are realigned by a cooperating scraper positioned intimately above. Relative movement between the scraper and the planar surface causes the workpieces to be discharged from the surface and precisely deposited upon the transport member.
    Type: Grant
    Filed: June 24, 1977
    Date of Patent: August 8, 1978
    Assignee: Cincinnati Milacron Inc.
    Inventors: Arnold L. Kellermann, David I. McDonald, Robert J. Grone
  • Patent number: D349758
    Type: Grant
    Filed: April 23, 1992
    Date of Patent: August 16, 1994
    Assignee: Cincinnati Milacron Inc.
    Inventors: Raymond L. Hallbach, Robert C. Dreisig, David I. McDonald