Patents by Inventor Lee Gropper

Lee Gropper 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: 4345713
    Abstract: In accordance with the present invention, there is provided an air driven centrifuge having an access door to a rotor chamber housing a rotor seat and a rotor having a plurality of turbine flutes formed in the underside thereof. Air jet means in the rotor seat are provided for supporting and spinning the rotor on an air cushion in the chamber. Means are provided to prevent the opening of the access door when pressurized air is supplied to the air jets, and means are provided to delay for a predetermined period, the opening of the door after the supply of pressurized air to the air jets is discontinued.
    Type: Grant
    Filed: April 13, 1981
    Date of Patent: August 24, 1982
    Assignee: Beckman Instruments, Inc.
    Inventors: William S. Gutierrez, Lee Gropper, Hugh O. Brown
  • Patent number: 4322029
    Abstract: In accordance with the present invention, there is provided an air driven centrifuge including a rotor housing having an access door in which there is mounted the illuminating and sensing elements of a photo-optical tachometer with the elements so constructed and arranged that they are positioned over the rotor when the door is in a closed position. There is also provided a rotor cover having at least a portion of its surface conditioned to alternately absorb and reflect incident light, and digital display means to display the rotor speed in R.P.M.
    Type: Grant
    Filed: May 29, 1980
    Date of Patent: March 30, 1982
    Assignee: Beckman Instruments, Inc.
    Inventors: Lee Gropper, Robert C. Franklin
  • Patent number: 4305546
    Abstract: A large diameter air driven centrifuge rotor which holds a plurality of centrifuge tubes in a fixed horizontal position. The rotor is designed to operate in a stable and smooth condition on a rotor seat which is smaller than the diameter of the rotor. Although the rotor essentially covers the rotor seat portion of the centrifuge, the rotor is designed in such a manner that the air flow from the driving air being exerted on the rotor will properly exit from between the rotor and the seat without affecting a stable smooth operation of the rotor.
    Type: Grant
    Filed: July 1, 1980
    Date of Patent: December 15, 1981
    Assignee: Beckman Instruments, Inc.
    Inventors: Lee Gropper, Armen L. Leonian
  • Patent number: 4181700
    Abstract: A device for the sequential fractionation of the contents of a centrifuge tube containing centrifugally separated contents utilizing a syringe-like apparatus. The present invention utilizes removable syringe tips that are mounted on a chamber housing for extraction and retention of a precise volume of centrifuged fluid from the centrifuge tube. The syringe-like apparatus is mounted to a frame in such a manner that the chamber housing is movable relative to the plunger or piston to permit precise movement of the chamber housing with the removable syringe tip into the centrifuge tube for delicate and precise removal of the desired fraction of the fluid. The syringe tips are removed with each fraction that is collected from the contents in the centrifuge tube and can be placed in a storage rack for subsequent analysis.
    Type: Grant
    Filed: April 3, 1978
    Date of Patent: January 1, 1980
    Assignee: Beckman Instruments, Inc.
    Inventors: Charles H. Chervenka, Lee Gropper
  • Patent number: 4142670
    Abstract: A centrifuge rotor assembly having a resilient liner with at least two separate chambers. Fluid communication between the separate chambers is automatically controlled in response to centrifugation operation of the rotor. When the rotor is stationary, the liner assumes a first position within the rotor where an annular chamber is sealed from a central chamber. When a fluid sample is placed within the liner of the rotor and the rotor is subjected to centrifugation, the centrifugally induced forces of the fluid mixture shift the liner to a second position, opening the sealed condition between the central and annular chambers to permit fluid communication between the respective chambers. When the centrifugation operation has been completed and the rotor returns to its stationary position, the inherent resilient structural characteristics of the liner automatically re-establish the seal between the respective chambers.
    Type: Grant
    Filed: January 27, 1978
    Date of Patent: March 6, 1979
    Assignee: Beckman Instruments, Inc.
    Inventors: Kenzo Ishimaru, Lee Gropper
  • Patent number: 4098457
    Abstract: An air driven centrifuge which utilizes a stator with a floating stator pad for alleviating excessive vibration of the rotor associated with critical rotating speeds. The floating stator pad incorporates means for increasing the friction between the pad and the stator in order to increase the ability of the stator pad to provide greater dampening of the rotor for improving the smoothness and stability of its operation.
    Type: Grant
    Filed: March 28, 1977
    Date of Patent: July 4, 1978
    Assignee: Beckman Instruments, Inc.
    Inventors: Lee Gropper, Kenzo Ishimaru
  • Patent number: 3990633
    Abstract: In a centrifuge including a centrifuge rotor and a drive shaft for spinning the rotor at selected rotational speeds, a safety device adapted to prevent the rotor from attaining a rotational speed likely to cause the rotor to explode with a force that could not be contained within the centrifuge housing. The device includes a hub member having a central opening adapted to receive the upper end of the drive shaft for supporting the rotor thereon, the hub member being formed with oppositely disposed heavier portions connected by relatively thinner web sections. The web sections are so designed and constructed, relative to the weight of the heavier sections, as to rupture at a predetermined rotational velocity of the rotor thereby causing the hub member to depart from the shaft, leaving no driving capacity or support for the rotor on the shaft, which then causes the rotor to separate from the drive shaft before attaining a hazardous rotational speed.
    Type: Grant
    Filed: April 9, 1975
    Date of Patent: November 9, 1976
    Assignee: Beckman Instruments, Inc.
    Inventors: Lawrence E. Stahl, Lee Gropper