MANDREL THAT HAVE ROLLER SLIDE PLATE AND 3

摘要

The purpose of the present invention is to enable a long term usage of a mandrel by increasing the durability by forming rollers of the mandrel to have a bearing force and facilitate the smooth rotation of the upper and lower rollers. An installation unit with a guide groove is formed on both inner walls of a leading end of a mandrel body. Guide protrusion units are formed in both sides of the installation unit. A slide plate with a gear unit in a lower side and a gear shaft with a gear unit to be engaged with the gear unit formed in the lower side of the slide plate are installed in the mandrel body. Connection pieces are formed in both sides of the gear shaft to be able to rotate with the gear shaft. The upper and lower rollers and a central roller are installed in leading parts of the connection pieces to support the roller between the rollers. According to the present invention, the slide plate protrudes from a bent part of a rectangular pipe when bending the rectangular pipe, thereby preventing the bent part of the rectangular pipe from being recessed, thus an effect of improving the accuracy of installing a lid hinge with an excellent quality in a trunk lid is obtained. In addition, the rotation of the roller is facilitated by the middle roller and the upper and lower rollers forming the mandrel, thus the effects of preventing damage to the roller, preventing damage to the roller caused by compression and abrasion when rubbing the roller with an inner surface of the rectangular pipe, and preventing noise and frictional heat are obtained.