An adjustable spacer with a non-hardened intermediate portion therebetween is mountable between a pair of roller bearings also mounted on a shaft such an axle or spindle or the like. The intermediate portion allows the spacer to collapse in the axial direction to maintain desired axial loads on the bearings.

An adjustable spacer with a non-hardened intermediate portion therebetween is mountable between a pair of roller bearings also mounted on a shaft such an axle or spindle or the like. The intermediate portion allows the spacer to collapse in the axial direction to maintain desired axial loads on the bearings.

A method of measuring a center error between bearings includes disposing both sides of a rotation shaft on inner circumferential surfaces of a magnetic bearing and a backup bearing, applying current to the magnetic bearing to produce movement of the rotation shaft, determining a contact point between the rotation shaft and the backup bearing according to movement of the rotation shaft, determining a final target value using the contact point and predetermined position information of the magnetic bearing, determining a magnetic center of the magnetic bearing through the final target value, comparing the magnetic center of the magnetic bearing and a mechanical center of the backup bearing to determine a center error, and aligning the magnetic center of the magnetic bearing and the mechanical center of the backup bearing based on the determined center error.

An adjustable spacer with a non-hardened intermediate portion therebetween is mountable between a pair of roller bearings also mounted on a shaft such an axle or spindle or the like. The intermediate portion allows the spacer to collapse in the axial direction to maintain desired axial loads on the bearings.

An adjustable spacer with hardened end portions and a non-hardened intermediate portion therebetween is mountable between a pair of roller bearings also mounted on a shaft such an axle or spindle or the like. The hardened material contacts the faces of the roller bearings but helps prevent wear therebetween and unwanted movement of the bearings on the shaft. The unhardened material allows the spacer to collapse in the axial direction to maintain desired axial loads on the bearings.

An adjustable spacer with hardened end portions and a non-hardened intermediate portion therebetween is mountable between a pair of roller bearings also mounted on a shaft such an axle or spindle or the like. The hardened material contacts the faces of the roller bearings but helps prevent wear therebetween and unwanted movement of the bearings on the shaft. The unhardened material allows the spacer to collapse in the axial direction to maintain desired axial loads on the bearings.

An adjustable spacer with hardened end portions and a non-hardened intermediate portion therebetween is mountable between a pair of roller bearings also mounted on a shaft such an axle or spindle or the like. The hardened material contacts the faces of the roller bearings but helps prevent wear therebetween and unwanted movement of the bearings on the shaft. The unhardened material allows the spacer to collapse in the axial direction to maintain desired axial loads on the bearings.

The invention relates to a bearing for supporting a shaft, in particular a rudder shaft, or a rudder blade, by means of which bearing the bearing clearance or the bearing wear can be continuously monitored, determined, and optionally documented. According to the invention, for a bearing for supporting a shaft, in particular a rudder shaft, comprising a first bearing element and a second bearing element, wherein the first bearing element has a sliding surface for contacting the second bearing element in a sliding manner, and a measurement-value sensor having a wear surface for contacting the second bearing element in a sliding manner, the at least one measurement-value sensor is not pin-shaped.

A method of measuring a center error between bearings includes disposing both sides of a rotation shaft on inner circumferential surfaces of a magnetic bearing and a backup bearing, applying current to the magnetic bearing to produce movement of the rotation shaft, determining a contact point between the rotation shaft and the backup bearing according to movement of the rotation shaft, determining a final target value using the contact point and predetermined position information of the magnetic bearing, determining a magnetic center of the magnetic bearing through the final target value, comparing the magnetic center of the magnetic bearing and a mechanical center of the backup bearing to determine a center error, and aligning the magnetic center of the magnetic bearing and the mechanical center of the backup bearing based on the determined center error.

This backlash measurement device measures the backlash existing between a first part and a second part that is provided with: a left pressing piece (37L) and a right pressing piece (37R) that rotate together with the second part, that pass through the center of rotation (41), and that extend the same distance from the center of rotation; a left pressing mechanism (38L) that presses the left pressing piece and a right pressing mechanism (38R) that presses the right pressing piece; a displacement amount detection mechanism (39) that comes into contact with the right pressing piece and that measures the displacement amount of the left pressing piece and the displacement amount of the right pressing piece; and a calculation unit (49) that determines backlash on the basis of the left displacement amount and the right displacement amount detected by the displacement amount detection mechanism.