Abstract: A motion guide device includes: a supporting body; a movable body which is movable along the supporting body; a roller which is configured to be rollable between the supporting body and the movable body; a roller holding member which is provided on the movable body to hold the roller, wherein the roller holding member comprises an upper roller holding member and a lower roller holding member, a protrusion is formed on the lower roller holding member, the protrusion is in a length direction of the movable body and opposite to a foot of the movable body, an opening is formed on the foot, the opening is opened to a side of the supporting body in the length direction to receive the protrusion, a protrusion width of the protrusion is greater than an opening width of the opening.

Abstract: A motion guide device includes: a supporting body; a movable body which is movable along the supporting body; a roller which is configured to be rollable between the supporting body and the movable body; a roller holding member which is provided on the movable body to hold the roller, wherein the roller holding member comprises an upper roller holding member and a lower roller holding member, a protrusion is formed on the lower roller holding member, the protrusion is in a length direction of the movable body and opposite to a foot of the movable body, an opening is formed on the foot, the opening is opened to a side of the supporting body in the length direction to receive the protrusion, a protrusion width of the protrusion is greater than an opening width of the opening.

Abstract: Provided is a ball screw capable of reducing unevenness of load distribution of balls and extending a service life of the ball screw. In the ball screw, one end part 6 of a nut 2 on a flange 2-2 side is closer to an end 9 of a screw shaft 1 on a fixed side than the other end part 7 of the nut 2 on a side opposite the flange 2-2 is, two or more circulation paths 5a to 5c are arranged in an axial direction of the nut 2, and a diameter of a ball 3a in the circulation path 5a closest to the flange 2-2 of the nut 2 is smaller than a diameter of a ball 3c in the circulation path 5c remotest from the flange 2-2 of the nut 2.

Abstract: A disclosed screw device provides an allowance for the accuracy of a recess in an end surface of a nut. A nut has a communicating hole communicating in an axial direction, and is provided at an axial end surface of the nut with a recess communicating with the communicating hole. A circulation member including a turn-around path is placed in the recess. When the circulation member is placed in the recess, the turn-around path of the circulation member is linked to a loaded rolling element rolling groove and the communicating hole of the nut to form a circulation path of a rolling element. A clearance between the circulation member and a wall surface of the recess permits the circulation member to move. The circulation member placed in the recess is not fixed in the recess, and is covered with a lid member to be attached to the nut.

Abstract: A disclosed screw device provides an allowance for the accuracy of a recess in an end surface of a nut. A nut has a communicating hole communicating in an axial direction, and is provided at an axial end surface of the nut with a recess communicating with the communicating hole. A circulation member including a turn-around path is placed in the recess. When the circulation member is placed in the recess, the turn-around path of the circulation member is linked to a loaded rolling element rolling groove and the communicating hole of the nut to form a circulation path of a rolling element. A clearance between the circulation member and a wall surface of the recess permits the circulation member to move. The circulation member placed in the recess is not fixed in the recess, and is covered with a lid member to be attached to the nut.

Abstract: Provided is a ball screw capable of reducing unevenness of load distribution of balls and extending a service life of the ball screw. In the ball screw, one end part 6 of a nut 2 on a flange 2-2 side is closer to an end 9 of a screw shaft 1 on a fixed side than the other end part 7 of the nut 2 on a side opposite the flange 2-2 is, two or more circulation paths 5a to 5c are arranged in an axial direction of the nut 2, and a diameter of a ball 3a in the circulation path 5a closest to the flange 2-2 of the nut 2 is smaller than a diameter of a ball 3c in the circulation path 5c remotest from the flange 2-2 of the nut 2.

Abstract: A ball screw device includes a ball circulation part having a ball circulation path. The ball circulation part is formed by combining a first split body and a second split body. The first split body has a fixing section fixed to an outer surface of a nut member. The second split body has a pair of leg sections configured to scoop up balls moving along a ball load rolling path and return the balls to the ball load rolling path, a connecting section configured to connect the pair of leg sections and disposed between the first split body and the nut member, and a pair of shoulder sections facing side surfaces of the first split body in two directions so as to sandwich the first split body between the pair of shoulder sections.

Abstract: A ball screw device or linear motion guide device has a seal member preventing dust and dirt from entering into a movable member of a linear motion guide device and seals out fine dust, dirt or like by surely contacting a seal to a shaft member without providing a large margin to the seal. The seal member includes a body portion mounted to the movable member and a lip portion contacting an outer portion of the shaft member, the lip portion has an oblique surface having an axial section inclining with respect to its axial direction, the body portion has an urging member urging the lip portion in a diameter direction of the shaft member and a reinforcing portion reinforcing the body portion. The urging member is located on the reinforcing portion side than the tip end of the lip portion in the axial sectional shape of the lip portion.

Abstract: A ball screw device includes a ball circulation part having a bail circulation path. The ball circulation part is formed by combining a first split body and a second split body. The first split body has a fixing section fixed to an outer surface of a nut member. The second split body has a pair of leg sections configured to scoop up balls moving along a ball load rolling path and return the balls to the ball load rolling path, a connecting section configured to connect the pair of leg sections and disposed between the first split body and the nut member, and a pair of shoulder sections facing side surfaces of the first split body in two directions so as to sandwich the first split body between the pair of shoulder sections.

Abstract: A ball screw device or linear motion guide device has a seal member preventing dust and dirt from entering into a movable member of a linear motion guide device and seals out fine dust, dirt or like by surely contacting a seal to a shaft member without providing a large margin to the seal. The seal member includes a body portion mounted to the movable member and a lip portion contacting an outer portion of the shaft member, the lip portion has an oblique surface having an axial section inclining with respect to its axial direction, the body portion has an urging member urging the lip portion in a diameter direction of the shaft member and a reinforcing portion reinforcing the body portion. The urging member is located on the reinforcing portion side than the tip end of the lip portion in the axial sectional shape of the lip portion.

Abstract: A rolling-element screw device includes: a large number of rolling elements; a screw shaft having an outer periphery on which a rolling groove for the large number of rolling elements is helically formed; a nut member which has a through-hole through which the screw shaft is passed and which is threadedly engaged with the screw shaft through intermediation of the large number of rolling elements; a lubricant supply hole formed through the nut member from an outer peripheral surface of the nut member to an inner peripheral surface of the nut member; a lubricant tank mounted to the outer peripheral surface of the nut member and comprising an accommodating chamber for lubricant; and a lubricant applying body standing from the lubricant tank, and inserted into the lubricant supply hole along with amounting operation of the lubricant tank with respect to the nut member.

Abstract: Provided is a roller screw capable of preventing rollers moving from an unloaded return path to a loaded roller rolling path from coming into collision with a scooping portion. The roller screw has: a screw shaft 1 having a spiral roller rolling surface 1a formed on an outer peripheral surface thereof; a nut 2 having a loaded roller rolling surface 2a formed in an inner peripheral surface thereof; a circulation member 3 having an unloaded return path connecting one end of the loaded roller rolling surface 2a of the nut 2 to an opposite end thereof; and a plurality of rollers 4 arranged in a loaded roller rolling path 6 and the unloaded return path.

Abstract: There is provided a new rolling body screw device manufactured with cheap cost without degrading quality in comparison with a conventional device even for a device having any large dimension in an end-cap type rolling body screw device. The rolling body screw device includes the direction changing passages 42 each including: a scoop-up portion 43 scooping a ball rolling in a loaded rolling body passage as a loaded area of the endless track so as to hand over the balls to the direction changing passage 42 as a non-loaded area of the endless track; and a route path 44 forming a circulation path of the ball scooped by the scoop-up portion. Each of the return pieces is composed, in combination, of a metal part 41a formed of a metal material including the scoop-up portion 43, and non-metal parts 41b, 41c formed of a non-metal material including the route path 44.

Abstract: A ball screw device having a novel ball circulation structure suitable for a screw shaft with a large lead, optimum for downsizing and weight saving of a nut member, capable of being manufactured at low cost, and capable of exhibiting high reliability even under severe use conditions. In a ball screw device where a screw shaft and a nut member are screwed to each other through an intermediation of a large number of balls, a no-load ball path which forms an infinite circulation path for the balls is constituted by a no-load ball groove spirally formed in an inner peripheral surface of a through-hole of the nut member and by a pair of direction change grooves which communicatively couple a load rolling groove and the no-load ball groove to each other so as to complete the infinite circulation path as a closed loop.

Abstract: Provided is a rolling-element screw device which does not sacrifice a stroke distance of a nut member (2) although carrying a sufficient amount of lubricant, or hinder heat radiation of the nut member (2), and contributes to facilitation of a replacement operation of a lubricant tank (4).

Abstract: Provided is a roller screw capable of preventing rollers moving from an unloaded return path to a loaded roller rolling path from coming into collision with a scooping portion. The roller screw has: a screw shaft 1 having a spiral roller rolling surface la formed on an outer peripheral surface thereof; a nut 2 having a loaded roller rolling surface 2a formed in an inner peripheral surface thereof; a circulation member 3 having an unloaded return path connecting one end of the loaded roller rolling surface 2a of the nut 2 to an opposite end thereof; and a plurality of rollers 4 arranged in a loaded roller rolling path 6 and the unloaded return path.

Abstract: Provided is a ball screw device having a novel ball circulation structure suitable for a screw shaft with a large lead, optimum for downsizing and weight saving of a nut member, capable of being manufactured at low cost, and capable of exhibiting high reliability even under severe use conditions. In a ball screw device (1) where a screw shaft (2) and a nut member (3) are screwed to each other through an intermediation of a large number of balls (4), a no-load ball path (50) which forms an infinite circulation path for the balls (4) is constituted by a no-load ball groove (33a) spirally formed in an inner peripheral surface of a through-hole (30) of the nut member (3) and by a pair of direction change grooves (34) which communicatively couple a load rolling groove (20a) and the no-load ball groove (33a) to each other so as to complete the infinite circulation path as a closed loop.

Abstract: Provided is a rolling-element screw device in which a recess can be easily formed in an outer diameter portion of a nut main body for receiving a circulation member. At both ends of a straight passage 5 of the nut main body 2, a pair of circulation members 8 is provided respectively, in each of which a direction change passage 6 is formed for connecting the straight passage 5 to a loaded rolling-element rolling passage 3. The circulation members 8 in a pair are fit in a pair of recesses 15, respectively, formed in the outer diameter portion of the nut main body 2. The direction change passage 6 of each circulation member 8 has a curve passage 22 which is connected to the loaded rolling-element rolling passage 3. The curve passage 22 is formed in such a way that, when seen in the axial direction of the nut main body 2, the track of the center of each rolling element 7 moving in the curve passage takes the shape of an arc.

Abstract: There is provided a new rolling body screw device manufactured with cheap cost without degrading quality in comparison with a conventional device even for a device having any large dimension in an end-cap type rolling body screw device. The rolling body screw device includes the direction changing passages 42 each including: a scoop-up portion 43 scooping a ball rolling in a loaded rolling body passage as a loaded area of the endless track so as to hand over the balls to the direction changing passage 42 as a non-loaded area of the endless track; and a route path 44 forming a circulation path of the ball scooped by the scoop-up portion. Each of the return pieces is composed, in combination, of a metal part 41a formed of a metal material including the scoop-up portion 43, and non-metal parts 41b, 41c formed of a non-metal material including the route path 44.

Abstract: A slider unit having built in a moving-coil linear motor ensuring high propulsion, is kept slim in overall height. A moving-coil assembly is made slim, with high stiffness, and is composed of an iron core of platy-configuration, and at least one set of three-phase armature coils wound around the iron core in the form of flat rectangular configuration in a plane intersecting the sliding direction. Comparatively more coil sides of the armature coils contribute to high propulsion. Like poles on either field magnet are placed in opposition to each other across the air gap, whereby the magnetic attraction is cancelled to reduce the load on the linear motion guide unit.