Hemming apparatus for door belt part of vehicle

Abstract

The present invention provides a pre-hemming apparatus for a door belt part for a vehicle. The apparatus includes a cam driver and a main punch pressing steel, and a cam device. The cam driver and the main punch pressing steel are installed at an upper die, and they are configured to drive the cam device installed at a lower die. The cam device installed at the lower die performs a hemming operation on a panel through a forward and backward motion and a linkage motion. The hemming apparatus performs the hemming operation including a first shifting process, a pre-hemming process, a second shifting process, and a main hemming process by allowing the cam driver and the main punch pressing steel to be linked with the cam device.

1 . A hemming apparatus for a door belt part for a vehicle, comprising:
 a cam driver and a main punch pressing steel disposed at an upper die; and   a cam device disposed at a lower die;   wherein the cam driver and main punch pressing steel are configured for driving the cam device,   wherein the cam device is configured for performing a hemming operation on a vehicle panel through a forward and backward motion and a linkage motion,   wherein the hemming apparatus performs the hemming operation through a first shifting process, a pre-hemming process, a second shifting process, and a main hemming process by allowing the cam driver and the main punch pressing steel to be linked with the cam device.   
     
     
         2 . The hemming apparatus of  claim 1 , wherein the cam device comprises:
 a lower die base fixedly disposed at the lower die;   a main body supported slidably back and forth on the lower die base;   a first link comprising a shifting roller and a pre-hemming roller, the first link installed in the main body to have a rear-pin structure, and a second link installed in the main body to have the rear-pin structure, the second link disposed in parallel under the first link,   a pre-hemming/main hemming punch configured for performing a pre-hemming operation and a main hemming operation on the vehicle panel while moving in linkage with the first link and the second link; and   a plurality of return springs having a first end fixed on the main body and a second end fixed on pins of the first link and the second link to provide a restitution force to the first link and the second link.   
     
     
         3 . The hemming apparatus of  claim 2 , further comprising:
 a guide rail disposed on opposing sides of the lower die base configured to guide a forward and backward slide motion of the main body;   a guide pin penetrating the main body and configured for guiding the forward and backward slide motion of the main body; and   a return spring disposed at the circumference of the guide pin and configured to provide a restitution force to the main body.   
     
     
         4 . The hemming apparatus of  claim 1 , wherein the cam driver comprises a shifting bar comprising:
 a first pressing part disposed at a lower portion of a front side of the shifting bar, and configured for applying pressure for first shifting of the cam device  12 ,   a second pressing part disposed at an upper portion of the front side of the shifting bar, the second pressing part protruding from the shifting bar more than the first pressing part and being vertically disposed at a center of the cam device, the second pressing part configured for applying pressure for second shifting of the cam device; and   a pre-hemming bar at a lower end portion of the front side of the shifting bar and being disposed at both sides of and parallel to the shifting bar, and vertical to the cam driver, the pre-hemming bar comprising a pre-hemming pressing part for applying pressure for pre-hemming of the cam device.   
     
     
         5 . A method for hemming a door belt part for a vehicle comprising:
 using the hemming apparatus of  claim 1  to hem a door belt part by using a one-stroke process wherein the first shifting process, the pre-hemming process, the second shifting process, and the main hemming process are all performed in the one-stroke process.