An electric actuator 1 includes: an electric motor 10; a first motion conversion mechanism 20 that has a screw shaft 21 rotatably driven by the electric motor 10 and a nut 22 screwed with the screw shaft 21, and converts a rotary motion of the screw shaft 21 into a linear motion of the nut 22; and a housing 40 accommodating the electric motor 10 and the motion conversion mechanism 20. The housing 40 includes a pair of housing split bodies 41 and 42 split by a plane parallel to an axial direction of the screw shaft 21.

An electric actuator 1 includes: an electric motor 10; a first motion conversion mechanism 20 that has a screw shaft 21 rotatably driven by the electric motor 10 and a nut 22 screwed with the screw shaft 21, and converts a rotary motion of the screw shaft 21 into a linear motion of the nut 22; and a housing 40 accommodating the electric motor 10 and the motion conversion mechanism 20. The housing 40 includes a pair of housing split bodies 41 and 42 split by a plane parallel to an axial direction of the screw shaft 21.

A roller and cage assembly (1) includes a roller (2) and a cage (3). The cage has a plurality of annular portions (30), a plurality of pillars (31) that couple the plurality of annular portions, and a pocket (40) formed between adjacent pillars. The pillars include a protrusion (35) that protrudes from a side wall surface towards the pocket and contacts the roller, which side wall surface configures the pocket, and within the protrusion, a plane facing the roller in a circumferential direction has a first plane (36), and a second plane (37) connecting to the first plane, the first plane being a flat plane, and the second plane being a curved plane, or a flat plane inclined against the first plane.

A roller and cage assembly (1) includes a roller (2) and a cage (3). The cage has a plurality of annular portions (30), a plurality of pillars (31) that couple the plurality of annular portions, and a pocket (40) formed between adjacent pillars. The pillars include a protrusion (35) that protrudes from a side wall surface towards the pocket and contacts the roller, which side wall surface configures the pocket, and within the protrusion, a plane facing the roller in a circumferential direction has a first plane (36), and a second plane (37) connecting to the first plane, the first plane being a flat plane, and the second plane being a curved plane, or a flat plane inclined against the first plane.

A structural suspension of radial turret bearing wheels in a turret bearing comprises a rail support structure mounted on a turret bearing support structure, a circular rail mounted to the rail support structure, and a plurality of radial wheels running on the mainly vertical inner side of the rail. The suspension includes a vertical flexible shaft, for each radial wheel, supported by an upper and lower support with a part of the shaft protruding with the radial wheel mounted close to the outer end. The inner side of the rail is a frustum with the shortest radius at the top and an aperture of 2, and the outer mainly planar contacting surface of the wheel has an angle relative to the rotational axis of the wheel, and is overlaid with a convex curvature across the contacting surface.

A structural suspension of radial turret bearing wheels in a turret bearing comprises a rail support structure mounted on a turret bearing support structure, a circular rail mounted to the rail support structure, and a plurality of radial wheels running on the mainly vertical inner side of the rail. The suspension includes a vertical flexible shaft, for each radial wheel, supported by an upper and lower support with a part of the shaft protruding with the radial wheel mounted close to the outer end. The inner side of the rail is a frustum with the shortest radius at the top and an aperture of 2, and the outer mainly planar contacting surface of the wheel has an angle relative to the rotational axis of the wheel, and is overlaid with a convex curvature across the contacting surface.

A rail-based floor conveyor system, with a floor conveyor with concavely grooved wheels and rails having a surface which, when in contact, dips at least partially into the grooved area of the wheels, thereby producing at least two load-bearing lines during the movement of the floor conveyor, wherein a wheel holder is provided for each wheel, with at least one horizontal axis of rotation for each wheel and a vertical axis of rotation to a bearing connected to the floor conveyor, and wherein the wheels can be moved by drives or manually on the rail, bearing including a first bearing part and a second bearing part, wherein one of the bearing parts has a concave surface section, which is at least partially in contact with a convex surface section of the respective other bearing part, and wherein both bearing parts are movable relative to one another while maintaining contact.

A rail-based floor conveyor system, with a floor conveyor with concavely grooved wheels and rails having a surface which, when in contact, dips at least partially into the grooved area of the wheels, thereby producing at least two load-bearing lines during the movement of the floor conveyor, wherein a wheel holder is provided for each wheel, with at least one horizontal axis of rotation for each wheel and a vertical axis of rotation to a bearing connected to the floor conveyor, and wherein the wheels can be moved by drives or manually on the rail, bearing including a first bearing part and a second bearing part, wherein one of the bearing parts has a concave surface section, which is at least partially in contact with a convex surface section of the respective other bearing part, and wherein both bearing parts are movable relative to one another while maintaining contact.

A roller bearing having a rotatable first ring and a non-rotatable second ring arranged concentrically, the second ring having a circumferential groove opening towards the first ring into which is arranged a protruding element, between which are arranged a single first radial roller bearing and two axial roller bearings spaced apart in the axial direction respectively on opposite radial faces of the protruding element. The roller bearing includes a plurality of circumferentially spaced apart second radial roller bearings secured to the rotatable first ring.

A roller bearing having a rotatable first ring and a non-rotatable second ring arranged concentrically, the second ring having a circumferential groove opening towards the first ring into which is arranged a protruding element, between which are arranged a single first radial roller bearing and two axial roller bearings spaced apart in the axial direction respectively on opposite radial faces of the protruding element. The roller bearing includes a plurality of circumferentially spaced apart second radial roller bearings secured to the rotatable first ring.