Patents Assigned to Jarret
  • Patent number: 5918850
    Abstract: A device for positioning in a civil engineering structure at least one fixed point which, in normal time, locks a point of part of the structure in position relative to another, supporting, part which is considered fixed. In order to return the structure part to its initial position as soon as the disturbing action thereon ceases, the device (32) comprises at least two prestressed damping springs which are mounted in opposition either side of the fixed point and act, first, on the structure part which can move in relative manner, such as a bridge floor (10) and, second, on a structure part considered fixed, such as a bridge pier (11).
    Type: Grant
    Filed: June 25, 1997
    Date of Patent: July 6, 1999
    Assignee: Jarret
    Inventors: Bruno Domange, Alfred Krief
  • Patent number: 5829556
    Abstract: A damper variably moderates movement of a piston on a rod in a cylinder filled with highly pressurized elastomeric gum. An axial bore through the piston allows relative ease of movement when a relatively low force is applied to a rod driving the cylinder. A high stress or acceleration on the rod forces a steel washer carried on the cylinder to deform and block the bore. The stiffness of the washer is proportioned to the ability of the clearance of the piston in the cylinder and the pressure and stiffness of the gum to establish a threshold. Damping is provided according to a preselected function, namely low initial resistance, and sharp increase is resistance to movement of the piston in response to stress exceeding the threshold. This function is suitable for damping in such applications as earthquake protection for structures and high stress protection for railroad beds.
    Type: Grant
    Filed: May 15, 1997
    Date of Patent: November 3, 1998
    Assignee: Jarret
    Inventor: Bruno Domange
  • Patent number: 4932637
    Abstract: A hydrostatically compressed elastomeric spring, having an S-bent tubular envelope, of flattened cross-section, filled with a mass of electrically conductive elastomer and closed by metal endpieces. By causing an electrical current to pass through the conductive elastomer, via the endpieces, the elastomer is heated up by Joule effect, thereby inducing a thermal expansion which results in a modification of the properties of the spring.
    Type: Grant
    Filed: January 24, 1989
    Date of Patent: June 12, 1990
    Assignee: Societe d'Exploitation des Ressorts Auto-Amortisseurs Jarret
    Inventor: Jacques H. Jarret
  • Patent number: 4725048
    Abstract: This invention relates to a damped elastic stop device, associated with two parts mobile with respect to each other in a determined direction. One part bears two circular bosses, over the periphery of which pass two loops of yarn or cable made of fibers of polyamide or aramid resin, attached to a central block connected to the other part. The device acts both as a spring, thanks to the elasticity of the yarn of the loops, and as a damper, thanks to the friction of the yarn of the loops sliding on the periphery of the bosses.
    Type: Grant
    Filed: July 1, 1986
    Date of Patent: February 16, 1988
    Assignee: Societe d'Exploitation des Ressorts Auto-Amortisseurs Jarret
    Inventors: Jean Jarret, deceased, Jacques Jarret
  • Patent number: 4611792
    Abstract: An improved hydrostatically compressed elastomeric spring in which an inner metal core buried in the elastomer contained in a flattened and bent tube constitutes a heating resistor for the elastomer to control its expansion and the compression of the spring under the effects of a static load. The spring is useful in shock absorbing devices.
    Type: Grant
    Filed: August 1, 1983
    Date of Patent: September 16, 1986
    Assignee: Societe d'Exploitation des Ressorts Auto-Amortisseurs Jarret
    Inventors: Jean Jarret, Jacques Jarret
  • Patent number: 4172590
    Abstract: The invention is concerned with an absorbing spring involving the hydrostatic compression of an elastomer, comprising a tight casing constituted by a deformable, bent elastic tube of flattened section, filled with elastomer. A central core is embedded in the elastomer, the core being made of elastic material, the coefficient of heat expansion of which is lower than that of the tube. The invention finds particular application in the manufacture of absorbing devices.
    Type: Grant
    Filed: April 13, 1977
    Date of Patent: October 30, 1979
    Assignee: Societe d'Exploitation des Ressorts Auto-Amortisseurs Jarret
    Inventors: Jean M. Jarret, Jacques H. Jarret
  • Patent number: 4004794
    Abstract: There is disclosed an improved spring of the type in which an elastomer is subjected to hydrostatic compression and is constituted by a mass of elastomer contained in an enclosure which comprises a casing in which a piston is mounted to slide. In said mass of elastomer is included a body, whose volume, in a certain range of temperatures, increases as the temperature drops. In a preferred embodiment of the invention, this body is advantageously water contained in at least one sealed and deformable bag.
    Type: Grant
    Filed: April 5, 1973
    Date of Patent: January 25, 1977
    Assignee: Societe d'Exploitation des Ressorts Auto-Amortisseurs Jarret
    Inventors: Jean Jarret, Jacques Jarret