Combination spherical and laminated bearing

Abstract

A bearing includes a laminated bearing portion and a spherical bearing portion, and the spherical bearing portion is disposed within the laminated bearing portion or the laminated bearing portion is disposed within the spherical bearing portion. The spherical bearing portion includes a ball disposed on a spherical race, and the ball and the outer race are configured such that a given break-out force is required to move the ball relative to the outer race.

I claim: 
     
         1 . A bearing comprising:
 a laminated bearing portion; and   a spherical bearing portion,   wherein the spherical bearing portion is disposed within the laminated bearing portion or the laminated bearing portion is disposed within the spherical bearing portion.   
     
     
         2 . The bearing as recited in  claim 1  wherein the spherical bearing portion comprises a generally annular outer race having a concave inner circumferential surface, the inner surface being partially spherical; and
 a ball disposed on the outer race and having a convex, partially spherical, outer surface in contact with the inner circumferential surface of the outer race, 
 wherein the ball and the outer race are configured such that a given break-out force is required to move the ball relative to the outer race. 
 
     
     
         3 . The bearing as recited in  claim 2  wherein either:
 the laminated bearing portion has a central bore and the spherical bearing portion is disposed within the central bore of the laminated bearing portion; or 
 the spherical bearing portion has a central bore and the laminated bearing portion is disposed within the central bore of the spherical bearing portion. 
 
     
     
         4 . The bearing as recited in  claim 3  wherein the spherical bearing portion is disposed in the central bore of the laminated bearing portion and wherein the ball has a generally axially extending central bore configured to receive a shaft portion. 
     
     
         5 . The bearing as recited in  claim 3 , wherein the laminated bearing portion is disposed in the central bore of the spherical bearing portion and wherein the laminated bearing portion has a generally axially extending central bore configured to receive a shaft portion. 
     
     
         6 . The bearing as recited in  claim 3  wherein the laminated bearing portion includes a plurality of alternating, generally tubular elastomeric laminae and metallic laminae nested coaxially about a central axis. 
     
     
         7 . The bearing as recited in  claim 6  wherein each of the plurality of elastomeric and metallic laminae have opposing axial ends and an axial length between the opposing ends, the plurality of elastomeric and metallic laminae being arranged such that the axial length of each one of the elastomeric and metallic laminae is greater than the axial length of all elastomeric and metallic laminae disposed radially within the each one of the laminae. 
     
     
         8 . The bearing as recited in  claim 7  wherein each one of the elastomeric and metallic laminae is partially spherical. 
     
     
         9 . The bearing as recited in  claim 2  further comprising an outer housing having a central opening, the laminated and spherical bearing portions being disposed within the central opening of the outer housing. 
     
     
         10 . The bearing as recited in  claim 2 , wherein the laminated bearing is configured to absorb forces ranging from a first, non-zero level to a second level and wherein the given break-out force is between the first level and the second level. 
     
     
         11 . The bearing as recited in  claim 10 , wherein the second level is about 75% of the elastic limit of the laminated bearing. 
     
     
         12 . The bearing as recited in  claim 10 , wherein the second level is about 50% of the elastic limit of the laminated bearing. 
     
     
         13 . The bearing as recited in  claim 10 , wherein the second level is about 25% of the elastic limit of the laminated bearing. 
     
     
         14 . The bearing as recited in  claim 10 , wherein the second level is from about 5% to 50% of the elastic limit of the laminated bearing. 
     
     
         15 . The bearing as recited in  claim 2 , wherein the laminated bearing has a lifespan inversely related to the level of force applied to the laminated bearing, and wherein the breakout force is selected based on a desired lifespan of the laminated bearing. 
     
     
         16 . The bearing as recited in  claim 2 , wherein the bearing has a central bore formed in the laminated bearing portion or in the spherical bearing portion and wherein the bearing has an outer surface formed on the laminated bearing portion or on the spherical bearing portion and wherein the laminated bearing is configured to repeatedly elastically accommodate relative movement between the bearing central bore and the bearing outer surface of up to a first magnitude and repeatedly slidably accommodate relative movement between the bearing central bore and the bearing outer housing of a second magnitude greater than the first magnitude. 
     
     
         17 . A method of operating a bearing comprising a laminated bearing portion and a spherical bearing portion, the spherical bearing portion being disposed within the laminated bearing portion or the laminated bearing portion being disposed within the spherical bearing portion, the spherical bearing portion comprising a generally annular outer race having a concave inner circumferential surface, the inner surface being partially spherical and defining a central opening, and a ball disposed within the outer race central opening and having a convex, partially spherical, outer surface in contact with the inner surface of the outer race portion, the ball and outer race being configured such that the ball is locked in the outer race and such that a given break-out force is required to move the ball relative to the outer race, the method comprising:
 repeatedly applying first forces to the bearing to deform the laminated bearing portion without exceeding the given break-out force of the spherical bearing.   
     
     
         18 . The method as recited in  claim 17 , including repeatedly applying second forces to the bearing, the second forces exceeding the given break-out force and causing the ball to move relative to the outer race. 
     
     
         19 . A bearing comprising:
 an inner bore,   an outer housing, and   means between the inner bore and outer housing for repeatedly elastically accommodating relative movement between the inner bore and the outer housing of up to a first magnitude and for repeatedly slidably accommodating relative movement between the inner bore and the outer housing of a second magnitude greater than the first magnitude.   
     
     
         20 . The bearing as recited in  claim 19 , wherein the means comprise a laminated bearing portion and a spherical bearing portion, and wherein
 either the spherical bearing portion is disposed within the laminated bearing and the inner bore is located in the spherical bearing portion; or   the laminated bearing portion is disposed within the spherical bearing portion and the inner bore is located in the laminated bearing portion.