A buoyancy-enhanced loop drive system includes upper and lower gears, a helical drive loop extending around and rotatably engaging the upper and lower gears, and a tank configured to retain a liquid medium. An ascending side of the drive loop extends through the tank. In some embodiments, the drive loop includes a plurality of sections, and adjacent sections are rotatable with respect to each other about an axis normal to an end face of the sections. Additionally or alternatively, the ascending side of the drive loop advances through an inlet seal via an exit port defined in an exit wall oriented perpendicular to the exit direction. Additionally or alternatively, an intermediate plate is coupled to an inlet housing for rotation about a vertical axis, and to a stationary support structure for bi-directional translation.

A lubricant supply member of a linear guide includes a first recessed part formed above a guide rail, a pair of second recessed parts formed at both left and right side-surface positions of the guide rail, and protrusions slidable on rail side raceway surfaces of the guide rail. A lubricating unit includes a first cylindrical part, arranged in the first recessed part, to allow the first recessed part to move in a vertical direction of the slider, and to press the first recessed part to a widthwise outside of the slider, and a pair of second cylindrical parts, arranged in the pair of second recessed parts, to allow the pair of second recessed parts to move in a width direction of the slider, and to press the pair of second recessed parts in the vertical direction of the slider, respectively.

Provided is a rolling guide device which is capable of preventing uneven wear of a holding belt by alleviating a tensile force that acts on the holding belt when the holding belt circulates in an endless circulation path together with rolling elements. The endless circulation path has a guide groove configured to guide movement of the holding belt in the endless circulation path. A condition of t.sub.max< is satisfied, where: t.sub.max represents a maximum clearance between both end portions of the holding belt which are opposed to each other in the endless circulation path; is expressed by $=2{}_0^{\frac{}{2}}\sqrt{{\left(a\sin \right)}^2+{\left(c\cos \right)}^2}d$

A linear motion guide unit prevents damage to a corner portion of an end surface of a carriage resulting from high-speed rolling of the rolling elements, and eliminates the need for strict dimensional management of facing end surfaces of the carriage and a spacer. A crowning is formed at an end portion of the carriage, and an R chamfered portion is formed at a corner of an end surface of the carriage. An R chamfered portion is formed at a corner of the end surface of the spacer. The R chamfered portions define a valley portion between the facing surfaces of the carriage and the spacer. The rolling elements roll above the valley portion while striding it to thereby be prevented from colliding against the corner portion of the end surface of the carriage, whereby damage to the corner portion of the end surface of the carriage can be prevented.

Provided is a rolling guide device which is capable of preventing uneven wear of a holding belt by alleviating a tensile force that acts on the holding belt when the holding belt circulates in an endless circulation path together with rolling elements. The endless circulation path has a guide groove configured to guide movement of the holding belt in the endless circulation path. A condition of t.sub.max< is satisfied, where: t.sub.max represents a maximum clearance between both end portions of the holding belt which are opposed to each other in the endless circulation path; is expressed by

[00001]$=2.Math.{}_0^{\frac{}{2}}.Math.\sqrt{{\left(a.Math..Math.\sin .Math..Math.\right)}^2+{\left(c.Math..Math.\cos .Math..Math.\right)}^2}.Math.d.Math..Math.-2.Math.{}_0^{\frac{}{2}}.Math.\sqrt{{\left(c.Math..Math.\sin .Math..Math.\right)}^2+{\left(b.Math..Math.\cos .Math..Math.\right)}^2}.Math.d.Math..Math.;$

2c represents an interval between the holding belt in a load path and the holding belt i

An oil supply device provided on a slider main body of a linear motion guide device includes: a storing member; an applicator; and a container. In the container, a storing member accommodation portion and an applicator accommodation portion are provided to be arranged in an up-down direction. A communication hole for guiding the lubricant from the storing member accommodation portion to the applicator accommodation portion is formed in the up-down direction in a partition portion which partitions the applicator accommodation portion and the storing member accommodation portion. The communication hole includes a small diameter portion which is positioned on the applicator accommodation portion side and a large diameter portion which is positioned on the storing member accommodation portion side. The storing member includes a protrusion portion capable of fitting into the large diameter portion.

Disclosed is a securing device for providing a movable unit of a linear guiding mechanism with additional safety in that the securing device prevents the movable unit from coming off a guiding rail in case of a bearing malfunction. The securing device comprises at least one securing portion and a coupling portion for coupling the at least one securing portion to the movable unit. The securing portion is engageable with the guiding rail in case of a failure of the movable unit.

An angular contact ball bearing arrangement has first and second raceway elements having raceways and a plurality of balls therebetween. When viewed in cross section through one of the balls the arrangement is divided into first, second, third and fourth quadrants by an axis of rotation of one of the balls and a perpendicular axis perpendicular to the axis of rotation of the ball. Each ball has two contact points on each raceway that are offset from the perpendicular axis by #10 degrees, and the contacts points are each located in a different quadrant. Also the centre point of the radius curvature of the first raceway on one side of the perpendicular axis and the centre point of the radius of curvature of the first raceway on the other side of the perpendicular axis are in located in different quadrants.

A linear motion guide unit prevents damage to a corner portion of an end surface of a carriage resulting from high-speed rolling of rollers, and eliminates the need for strict dimensional management of facing end surfaces of the carriage and a spacer. A crowning is formed at an end portion of the carriage, and an R chamfered portion is formed at a corner of an end surface of the carriage. An R chamfered portion is formed at a corner of the end surface of the spacer. The R chamfered portions define a valley portion between the facing surfaces of the carriage and the spacer. The rollers roll above the valley portion while striding it to thereby be prevented from colliding against the corner portion of the end surface of the carriage, whereby damage to the corner portion of the end surface of the carriage can be prevented.

An end seal device of a linear guide includes a main plate and a cladding member. The main plate includes an upper portion, two engaging portions extending downwardly and bent rearwardly from the upper portion, and two lower contact portions extending downwardly from the engaging portions and each having a penetrating hole. The cladding member includes cladding portions respectively attached to major surfaces of the main plate, and two filling portions each filling the penetrating hole to interconnect the cladding portions for firmly covering and protecting the main plate.