A clamping device and a clamp portion (100) of same. In the clamp portion, the rear end of a connecting part (150) is inserted into a connecting tube (160) and is fastened, the front end of the connecting part is movably connected to a clamping piece fixture (120), the connecting part has an easily breaking portion (151), an unlocking part (170) is sleeved on the connecting part and is limited horizontally by the connecting part and the connecting tube (160), two clamping pieces (110) are connected to the clamping piece fixture by a clamping piece connecting pin (180), the clamping piece fixture is provided inside a clamp tube (130) and can move back and forth, a clamping piece stop pin (140) is fixed at the front of the clamp tube to prevent the clamping piece fixture from sliding out of the clamp tube, the tube wall of the clamp tube is provided with an elastic spring (132), the spring is indented and then the spring and a locking surface (121) of the clamping piece fixture form a unidirectionally locked fitting structure, and the unlocking part is provided with a pushing surface (173) for pushing the clamping piece fixture to move forward and a wedge surface (171) for pulling the spring to implement unlocking. The technical solution has a simple and proper structure, and achieves reliable and stable clamping and locking and moreover, the clamping piece can be repeatedly opened and closed, and the clamp can perform relocation and clamping many times.La présente invention concerne un dispositif de serrage et une partie de serrage (100) de celui-ci. Dans la partie de serrage, lextrémité arrière dune partie de raccordement (150) est insérée dans un tube de raccordement (160) et est fixée, lextrémité avant de la partie de raccordement étant raccordée de façon mobile à une fixation de pièce de serrage (120), la partie de raccordement a une partie aisément rompue (151), une partie de déverrouillage (170) est emmanchée sur la partie de raccordement et est limitée horizon
