초록 ▼

A combined radial and thrust bearing assembly is set forth for a down-hole drilling assembly to journal a shaft, mounting the drill bit, in a housing. The bearing assembly is used between a down-hole fluid powered motor and a drill bit for drilling oil wells, for example. The bearing assembly includ

A combined radial and thrust bearing assembly is set forth for a down-hole drilling assembly to journal a shaft, mounting the drill bit, in a housing. The bearing assembly is used between a down-hole fluid powered motor and a drill bit for drilling oil wells, for example. The bearing assembly includes cooperative pairs of upper and lower inner races located on the shaft for mutual rotation. Each of the inner races includes a pair of interchangeable toroidal tracks. Cooperative pairs of upper and lower outer races are fixed against rotation in the housing. Each outer race has a pair of interchangeable toroidal tracks to selectively cooperate with the tracks of the inner races to define a toroidal channel to receive a number of bearing balls. Spring means are disposed between the upper and lower pairs of outer races and the housing and between the upper and lower pairs of outer races to provide a compliant coupling for the even distribution of radial and upwardly and downwardly directed thrust loads between the races and balls and eventual transfer to the housing. Drilling fluid is circulated through the bearing assembly for cooling and lubrication.

대표청구항 ▼

A combined radial and thrust bearing assembly comprising: a fixed housing; a rotatable shaft extending through the housing; a plurality of inner race tracks fixed on the shaft, each pair of adjacent inner race tracks defining an inner portion of the channel; a plurality of outer race tracks mounted

A combined radial and thrust bearing assembly comprising: a fixed housing; a rotatable shaft extending through the housing; a plurality of inner race tracks fixed on the shaft, each pair of adjacent inner race tracks defining an inner portion of the channel; a plurality of outer race tracks mounted in the housing including means for preventing rotation and means for permitting limited axial movement within the the housing, each pair of outer races having a pair of adjacent tracks defining an outer portion of the channel; a plurality of bearing balls in the channel formed by the inner and outer tracks, said tracks being shaped for transmitting radial and thrust loads via the bearing balls; upper spring means between an upper pair of outer races and the housing for transmitting an upwardly directed thrust load from the upper pair of outer races to the housing; a shoulder fixed inside the housing between adjacent pairs of outer races; and lower spring means between a lower pair of outer races and the shoulder for transmitting an upwardly directed thrust load from the lower pair of outer races to the shoulder and the housing, the upper and lower springs means being substantially equal for distributing the upwardly directed thrust loads substantially equally between the upper and lower pairs of outer races.