Patents by Inventor Ellwood S. Douglas

Ellwood S. Douglas 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: 5270495
    Abstract: A combination weighing machine has a plurality of weigh scales for weighing quantities of product, and the scales are selectively dumped and loaded in a cyclic operation to form a package containing a number or weight of product that closely approximates a target amount. The machine includes a plurality of feeders and corresponding accumulators that are associated respectively with the scales for loading product into the scales after they are dumped. To ensure a more accurate feeding of product to a scale, a sensor is provided for detecting the pieces of product as they are loaded into the associated accumulator from a feeder, and the feeder is regulated in accordance with the pieces of product detected to control the duration of feeder operation.
    Type: Grant
    Filed: February 28, 1992
    Date of Patent: December 14, 1993
    Assignee: Package Machinery Company
    Inventors: Oren A. Mosher, Ellwood S. Douglas
  • Patent number: 4813503
    Abstract: A method and apparatus for preparing a blended product charge includes a combinatorial weigher which receives a major product and a fill-to-cutoff weigher which receives a minor product. A controller selects a minor constituent product weight and then combinatorially searches through available major constituent product weighing scales for the combination of major product weighing scales which together with the minor product weighing scale yields a product charge nearest in weight to a target weight.
    Type: Grant
    Filed: May 31, 1988
    Date of Patent: March 21, 1989
    Assignee: Package Machinery Company
    Inventors: Ellwood S. Douglas, Oren A. Mosher
  • Patent number: 4550792
    Abstract: A combination weighing system searches a plurality of scales for a combination which provides a minimum total weight of product not less than a pre-established target weight. The search for the best combination is performed on the basis of an ordered search sequence of all combinations, and certain steps of the sequence and corresponding combinations are omitted from the sequence if they involve subcombinations previously searched and found to be at or above the target weight. The scales produce signals representative of the product weight, and the signals are calibrated and processed to eliminate measurement errors.
    Type: Grant
    Filed: June 6, 1984
    Date of Patent: November 5, 1985
    Assignee: Eagle Machinery Company
    Inventors: Oren A. Mosher, Oren G. Mosher, Ellwood S. Douglas
  • Patent number: 4535856
    Abstract: A combination weighing machine for forming a charge of product closely approximating a target amount includes a plurality of weigh scales, each of which receives a quantity of product and produces a signal proportional to the quantity of product received. The quantities are combined according to a combination searching sequence in a search operation, and a combination of scales which closely approximates a target amount is dumped to form the desired charge. The dumped scales are reloaded, and the process is repeated in a cyclic manner. The speed of the cyclic process is improved without significantly sacrificing accuracy by allocating less time than necessary for a complete search of all possible combinations in the search sequence. A search is terminated when the time expires, whether the search sequence is completed or not.
    Type: Grant
    Filed: February 16, 1984
    Date of Patent: August 20, 1985
    Assignee: Package Machinery Co.
    Inventors: Oren A. Mosher, Ellwood S. Douglas
  • Patent number: 4534428
    Abstract: A combination weighing machine has a plurality of scales that are periodically dumped and reloaded with products from a bulk container. In each cycle of machine operation, the loaded scales are surveyed, and a combination of the scales which most accurately yields a desired target weight is dumped into a single package. The dumped scales are then reloaded and the process is repeated. Each of the scales has an associated vibratory feeder and accumulator which receives the product from the bulk container and dispenses the product to the scale as needed. In order to feed the scales with loads that provide a large selection of combinations close to the target weight, a control for the vibratory feeders regulates the duration and amplitude of the vibrations in accordance with the loads measured in preceding machine cycles. Also described is a method of dealing with inactive scales by feeding small quantities of articles to the scales requiring reloading until the inactive scales are dumped.
    Type: Grant
    Filed: August 11, 1983
    Date of Patent: August 13, 1985
    Assignee: Package Machinery Co.
    Inventors: Oren A. Mosher, Ellwood S. Douglas
  • Patent number: 4533007
    Abstract: A combination weighing system searches a plurality of scales for a combination which provides a minimum total weight of product not less than a pre-established target weight. The search for the best combination is performed on the basis of an ordered search sequence of all combinations, and certain steps of the sequence and corresponding combinations are omitted from the sequence if they involve subcombinations previously searched and found to be at or above the target weight. The scales produce signals representative of the product weight, and the signals are calibrated and processed to eliminate measurement errors.
    Type: Grant
    Filed: March 16, 1984
    Date of Patent: August 6, 1985
    Assignee: Eagle Machinery Company
    Inventors: Oren A. Mosher, Oren G. Mosher, Ellwood S. Douglas
  • Patent number: 4529050
    Abstract: A combination weighing machine has a plurality of weigh scales which provide signals representative of the weight of product in each scale. A search control receives the weight signals and selects a combination of the scales which together compose a charge of the product equal to or closely approximating a given target weight. Transient errors existing in the weight signals at high speeds of operation are corrected by means of adjustment parameters that are periodically recalculated on the basis of known differences between settled and unsettled weight signals.
    Type: Grant
    Filed: January 20, 1984
    Date of Patent: July 16, 1985
    Assignee: Package Machinery Co.
    Inventors: Oren A. Mosher, Ellwood S. Douglas
  • Patent number: 4466500
    Abstract: A combination weighing system searches a plurality of scales for a combination which provides a minimum total weight of product not less than a pre-established target weight. The search for the best combination is performed on the basis of an ordered search sequence of all combinations, and certain steps of the sequence and corresponding combinations are omitted from the sequence if they involve subcombinations previously searched and found to be at or above the target weight. The scales produce signals representative of the product weight, and the signals are calibrated and processed to eliminate measurement errors.
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: August 21, 1984
    Assignee: Package Machinery Company
    Inventors: Oren A. Mosher, Oren G. Mosher, Ellwood S. Douglas
  • Patent number: 4000444
    Abstract: Electric circuit breaker including highly sensitive ground fault responsive means for protecting human life from electrical shock. The circuit breaker is suitable for mounting in a panelboard at the service entrance of a building to provide ground fault protection for the individual branch circuits in the building.
    Type: Grant
    Filed: March 12, 1973
    Date of Patent: December 28, 1976
    Assignee: 3-M Company
    Inventors: Ellwood S. Douglas, Richard C. Doyle, David William Nestor, Wallace W. Wahlgren