Patents Assigned to Nippon Thomson Co., Ltd.
  • Patent number: 5441350
    Abstract: The structure of the cross roller bearing does not require fixing bolts, rivets or holders for the divided races and can firmly assemble the divided races together. The cross roller bearing includes the inner race having a raceway groove and an engagement surface on its outer circumferential surface and the outer race that fits over the inner race and has a raceway groove and an engagement surface on its inner circumferential surface. The outer race is divided into two axially divided races. A large number of rollers are installed in a raceway formed between the raceway grooves. The engagement surface of the inner race is formed with recessed portions at axially inner portions, and the engagement surfaces of the divided races of the outer race are formed with raised portions that rotatably fit in the recessed portions. Thus, the divided races are assembled onto the inner race so that they are rotatable but axially locked relative to the inner race.
    Type: Grant
    Filed: June 3, 1994
    Date of Patent: August 15, 1995
    Assignee: Nippon Thomson Co., Ltd.
    Inventor: Ryuji Fujita
  • Patent number: 5391003
    Abstract: The rolling guide unit has a track rail formed with raceway surfaces, a casing moveable relative to the track rail and having raceway surfaces at positions facing the raceway surfaces of the track rail, and a number of cylindrical rolls that run rolling between the facing raceway surfaces. An end portion of that raceway surface of the track rail which is heavily loaded with a distributed load is crowned to make the raceway surface at the end portion curved, thereby eliminating uneven load and therefore dents and flaking of the raceway. This enhances durability and sliding characteristics of the raceway surfaces.
    Type: Grant
    Filed: March 30, 1993
    Date of Patent: February 21, 1995
    Assignee: Nippon Thomson Co., Ltd.
    Inventor: Yasumasa Ooya
  • Patent number: 4797015
    Abstract: A roller-cage assembly for use in a bearing includes a cylindrical cage provided with a plurality of openings extending axially and spaced apart from one another circumferentially and a plurality of rollers, each of which is received in a corresponding one of the openings. Each opening is defined by a pair of oppositely disposed side guide surfaces and a pair of oppositely disposed end guide surfaces, whereby the distance between the pair of oppositely disposed side guide surfaces is larger than the diameter of the roller and the distance between the pair of opposite end guide surfaces is larger than the length of the roller, so that the roller may rotate freely within the opening.
    Type: Grant
    Filed: November 20, 1987
    Date of Patent: January 10, 1989
    Assignee: Nippon Thomson Co., Ltd.
    Inventors: Kengo Hidano, Susumu Amano
  • Patent number: 4505522
    Abstract: There is disclosed an infinite circuit using rolling bearings for providing the rectilinear motion. This circuit comprises: rolling elements consisting of rollers or balls; rolling bearings, constituted by the rolling elements, for providing the infinite rectilinear motion by endlessly circulating the rolling elements in an infinite circuit while keeping the direct contact relation with each other; rectilinear track and return passages; two direction reversing passages which connect both ends thereof. The direction reversing passage consists of two quarter-circular passages and an intermediate rectilinear passage provided therebetween. The cross section of each rolling element has the same diameter. In this invention, the traveling amount of each rolling element at each position in the infinite circuit can be made uniform, thereby minimizing the stick slip of the rolling elements while they are rolling in the circuit, so that it is possible to obtain the infinite circuit with less sliding resistance.
    Type: Grant
    Filed: June 26, 1984
    Date of Patent: March 19, 1985
    Assignee: Nippon Thomson Co., Ltd.
    Inventor: Kazuhiko Tanaka