COUPLING DEVICE OF ROBOT ARM

PROBLEM TO BE SOLVED: To alleviate contact stress in a lock mechanism, and to facilitate manufacturing.SOLUTION: In a state that a robot arm master plate 2 and a tool attachment tool plate 4 are brought into contact with each other, a ball pressing member 16 at the plate 2 side intrudes into the plate 4 at its leading end, is driven so as to advance and retreat by a piston 18 between an unlock position and a lock position, and applied with drive force at the lock position. When a plurality of steel balls 36 around the leading end of the pressing member 16 advance to the plate 4 side according to a slide of the ball pressing member 16 to the lock position from the unlock position, a ball receiving part 44 of the plate 4 receives the steel balls 36. An arc circular part 60 in which a vertical cross section shape of a ball accommodation groove 58 which is annularly formed around the pressing member 16, and accommodates the steel balls 36 is formed into an arc circular shape is inclined to a slide direction, and an arc circular part 54 in which a vertical cross section shape of a ball accommodation groove 50 which is annularly formed around the ball receiving part 44 is formed into an arc circular shape is inclined to a side opposite to the arc circular part 60, and each diameter of the vertical cross section shapes of both the arc circular parts 54, 60 are smaller than each diameter of the steel balls 36.SELECTED DRAWING: Figure 4 【課題】 ロック機構における接触応力を軽減できる上に製造を容易にする。【解決手段】 ロボットアーム用マスタープレート２とツール取付用ツールプレート４とが接触した状態でプレート２側のボール押圧部材１６は、その先端がプレート４内に侵入し、非ロック位置とロック位置との間をピストン１８によって進退駆動され、ロック位置で駆動力が印加されている。ボール押圧部材１６の非ロック位置からロック位置への摺動に応じて、押圧部材１６の先端の周囲の複数の鋼球３６がプレート４側に進行したとき、プレート４のボール受け部４４が鋼球３６を受ける。押圧部材１６の周囲に環状に形成されて鋼球３６を収容しているボール収容溝５８の縦断面形状が円弧状の円弧状部６０が摺動方向に対して傾斜し、ボール受け部４４の周囲に環状に形成されたボール収容溝５０の縦断面形状が円弧状の円弧状部５４は、円弧状部６０と反対側に傾斜し、両円弧状部５４、６０の縦断面形状における径は、鋼球３６の径よりも小さい。【選択図】 図４