Patents by Inventor John L. Rodgers, Jr.

John L. Rodgers, Jr. 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).

  • Electro-hydraulic ram control apparatus
    Patent number: 4325896
    Abstract: A control system for the ram of a hydraulic injection molding press, the injection speed or velocity of which is to be precisely controlled according to a predetermined velocity command signal. A programmable relief valve is used to effect accurate control over the flow of hydraulic fluid under pressure to the ram cylinder and is responsive to signals representing diverse conditions of operation of the press. In one application of the concept, velocity and subsequent holding pressure control of a ram are obtained.
    Type: Grant
    Filed: May 27, 1980
    Date of Patent: April 20, 1982
    Assignee: Solid Controls, Inc.
    Inventor: John L. Rodgers, Jr.
  • Electro-hydraulic ram control apparatus
    Patent number: 4222725
    Abstract: A control system for the ram of a hydraulic injection molding press, the injection speed or velocity of which is to be precisely controlled according to a predetermined velocity command signal. A programmable relief valve is used to effect accurate control over the flow of hydraulic fluid under pressure to the ram cylinder and is responsive to signals representing diverse conditions of operation of the press.In one application of the concept, velocity and subsequent holding pressure control of a ram are obtained.
    Type: Grant
    Filed: February 27, 1978
    Date of Patent: September 16, 1980
    Assignee: Solid Controls, Inc.
    Inventor: John L. Rodgers, Jr.