Abstract: A pipe coupling comprising a socket having a plurality of locking balls capable of engaging a locking portion on a plug and connected to the plug with the locking balls in engagement with the locking portion. The socket includes a main cylinder having an end portion formed with an inlet to receive the plug and an outer cylinder located close to the end portion of the main cylinder and around the outer periphery thereof. The main cylinder and the outer cylinder define a gap having a tapered profile between them, and the locking balls are stored in the gap. The locking balls can project and recede from the inner periphery of the main cylinder. Further, the pipe coupling comprises a thrust cylinder slidable on the outer periphery of the main cylinder. When the locking balls engage the locking portion, the thrust cylinder prevents centrifugal movement of the locking balls.

Abstract: A pipe coupling comprising a socket having a plurality of locking balls capable of engaging a locking portion on a plug and connected to the plug with the locking balls in engagement with the locking portion. The socket includes a main cylinder having an end portion formed with an inlet to receive the plug and an outer cylinder located close to the end portion of the main cylinder and around the outer periphery thereof. The main cylinder and the outer cylinder define a gap having a tapered profile between them, and the locking balls are stored in the gap. The locking balls can project and recede from the inner periphery of the main cylinder. Further, the pipe coupling comprises a thrust cylinder slidable on the outer periphery of the main cylinder. When the locking balls engage the locking portion, the thrust cylinder prevents centrifugal movement of the locking balls.

Abstract: A tube coupler has a main tubular socket body connected to a first tube, a main tubular plug body connected to a second tube and removably connected to the main tubular socket body, and a locking mechanism for locking together the main tubular socket body and the main tubular plug body in a state in which the main tubular plug body is inserted in the main tubular socket body. The tube coupler further includes an operating ring threadably engaging the outer peripheral surface of the main tubular socket body, a slide ring mounted on the outer peripheral surface of the main tubular socket body and being moved axially by the operating ring, and a cylindrical holder slidably fitted in the main tubular socket body and engageable with the main tubular plug body. The holder has a groove open radially outward, and the main tubular socket body has axially elongated holes. The slide ring is provided with pins each having a distal end portion extending into the groove through the corresponding elongated hole.