A linear motion device, comprising:
- a guiding member extending along a first direction, wherein two rail grooves are at two opposite sides of the guiding member parallel to the first direction;
- and
- a slide block assembly slidably assembled on the guiding member, wherein the sliding block assembly comprises:
- a slide block slidably disposed across the guiding member, wherein the slide block has two ball grooves respectively corresponding to the two rail grooves;
- each of the two rail grooves and the corresponding ball groove together form an inner ball race;
- two ball race members extending along the first direction and respectively disposed at two opposite sides of the slide block, wherein each of the two ball race members has an outer ball race;
- a first circulation member and a second circulation member respectively disposed at two opposite sides of the slide block along the first direction, wherein the first circulation member and the second circulation member are respectively in communication with the two inner ball races and the two outer ball races;
- the first circulation member comprises:
- a plate-shaped portion abutting against the slide block, wherein the plate-shaped portion has a stopping plane;
- and
- two revolve channel members protruding from one side of the first circulation member away from the slide block, wherein each of the two revolve channel members has a revolve curved groove, and each of the two revolve curved grooves is in communication with the corresponding outer ball race through a communication channel;
- each of the revolve channel members comprises an upper protrusion member, a lower protrusion member, and a connection member, the connection member is connected to the upper protrusion member and the lower protrusion member;
- a longest extension distance of the upper protrusion member along the first direction is less than a longest extension distance of the lower protrusion member along the first direction;
- a first end cover and a second end cover respectively assembled on the first circulation member and the second circulation member, wherein one surface of the first end cover away from the slide block has two assembling grooves, and one surface of the second end cover away from the slide block has two assembling grooves;
- one surface of the first end cover near to the slide block has a recess to receive the plate-shaped portion, and the recess has a positioning plane cooperating with and leaning against the stopping plane;
- when the positioning plane of the first end cover correspondingly leans against the stopping plane of the plate-shaped portion, the first end cover at least covers the upper protrusion member and the connection member of the corresponding revolve curved groove;
- a plurality of balls;
- and
- two retaining members, wherein each of the two retaining members passes through the corresponding inner ball race;
- one of two ends of each of the retaining members is embedded into one of the two assembling grooves of the first end cover, and the other end of each of the retaining members is embedded into one of the two assembling grooves of the second end cover;
- wherein the two inner ball races, the first circulation member, the first end cover, the two outer ball races, the second circulation member, and the second end cover together form two ball circulation races, and the balls are rollably received in the two ball circulation races.