Patent EP-0849496-A2 (EP)
Inventor: IKEDA MASAHIKO
IPC: E04H9/02
Filed: 1994-05-10
Abstract: A vibration proofing structure for large load
comprising:
   a first base and a second base;   a plurality of rails mounted at predetermined
positions on said first base;   guide members each fittedly mounted on each of said
rails so as to be slidable in a longitudinal direction of
said rail;   a plurality of horizontal-type oil dampers each
rotatably mounted on each of said guide members;   said horizontal-type oil dampers each including a
tank rotatably mounted on each of said guide members,
pistons arranged in said tank, a rod having a first end and
a second end, said first end being mounted on said pistons
so as to render an axis of said rod perpendicular to a
longitudinal axis of said pistons and said second end of
said rod outwardly extending from said tank so as to be
slidably inserted through said second base;   a plurality of struts each mounted on said first
base for bearing load downwardly applied through said
second base, arranged so as to upwardly extend therefrom
and provided on an upper end thereof with a hemispherical
member;   holding plates each arranged on each of said
horizontal-type oil dampers;   said rod being inserted through said holding plate
so as to permit said horizontal-type oil damper to be
rotated about said rod with respect to said holding plate
and being inserted through said second base while being
rotatably supported by means of a bearing so as to permit
said horizontal-type oil damper to be rotated with respect
to said second base;   support rods mounted on an upper surface of each of
said holding plates so as to be spaced from each other in a 
longitudinal direction of said holding plate and upwardly
extend therefrom;   said support rods each being vertically slidably
inserted through said second base and provided at an upper
end thereof with a primary washer-like spring bearing;   said support rods each being fitted on a portion
thereof defined between said primary spring bearing and
said base with a support rod spring of a predetermined
spring constant; and   said rod being mounted on an upper end thereof with
a secondary washer-like spring bearing and fitted on a
portion thereof defined between said secondary spring
bearing and said second base with a rod spring of a
predetermined spring constant; and   a plurality of vertical-type oil dampers arranged
in proximity to said horizontal-type oil dampers;   said vertical-type oil dampers each including a
vertical-type cylinder, a piston arranged in said cylinder
to define an upper oil chamber and a lower oil chamber
therethrough in said cylinder and formed with an oil
passage means in a manner to vertically extend
therethrough, and a control means for externally
controlling the amount of oil transferred through said oil
passage means between said upper oil chamber and said lower
oil chamber;   said vertical-type oil dampers each being provided
therein with a large spring in a manner to be interposed
between said piston and a bottom of said vertical-type
cylinder, said large spring having a spring constant
greater than said spring constant of said rod spring and
each of said support rod springs.