A tool assembly for attaching to two carriages of a carriage guide rail system; wherein the two carriages are movable along the carriage guide rail relative to one another, the tool assembly comprising: a base (4; 4'; 14; 24) and a linear actuator (5; 5') movable relative to the base (4; 4'; 14; 24); wherein the base (4; 4'; 14; 24) comprises a first connector (3a; 3a') for attaching to one of the two carriages; wherein the linear actuator (5; 5') comprises a second connector (3b; 3b') for attaching to the other one of the two carriages; wherein the base (4; 4'; 14; 24) comprises a first base portion (40; 401'; 140; 240; 340) attached to the first connector (3a; 3a'); characterized in that at least one of the first connector and the second connector comprises a central passage, a first portion , a second portion , a locking base and a locking controller ; wherein the locking controller is pivotable relative to the central passage between a locked position and an unlocked position; wherein the locking base comprises a locking unit ; wherein the locking controller comprises a locking frame enclosing the locking unit ; wherein the base (4; 4') or the linear actuator (5; 5') comprises a connecting part ; wherein the connecting part comprises a neck portion ; wherein the neck portion is adjacent to and aligned with a locking opening of the locking base , such that the locking unit protrude from the locking opening and engage with the neck portion in the locked position; wherein when the locking controller is in the unlocked position, the locking unit is spaced apart from the neck portion of the connecting part; and wherein when the locking controller is in the locked position, the locking unit is engaged with the neck portion. a base (4; 4'; 14; 24) and a linear actuator (5; 5') movable relative to the base (4; 4'; 14; 24); wherein the base (4; 4'; 14; 24) comprises a first connector (3a; 3a') for attaching to one of the two carriages; wherein the linear actuator (5; 5') comprises a second connector (3b; 3b') for attaching to the other one of the two carriages; wherein the base (4; 4'; 14; 24) comprises a first base portion (40; 401'; 140; 240; 340) attached to the first connector (3a; 3a'); characterized in that at least one of the first connector and the second connector comprises a central passage, a first portion , a second portion , a locking base and a locking controller ; wherein the locking controller is pivotable relative to the central passage between a locked position and an unlocked position; wherein the locking base comprises a locking unit ; wherein the locking controller comprises a locking frame enclosing the locking unit ; wherein the base (4; 4') or the linear actuator (5; 5') comprises a connecting part ; wherein the connecting part comprises a neck portion ; wherein the neck portion is adjacent to and aligned with a locking opening of the locking base , such that the locking unit protrude from the locking opening and engage with the neck portion in the locked position; wherein when the locking controller is in the unlocked position, the locking unit is spaced apart from the neck portion of the connecting part; and wherein when the locking controller is in the locked position, the locking unit is engaged with the neck portion. <EOS>