Patent ID: 9010879
Filing Date: 2015-04-21
Classification: B60T

Abstract:
1. A pre-fill system installed between a master cylinder and a disc brake to increase an initial flux in braking, the pre-fill system comprising: a first housing connected with the master cylinder to receive hydraulic brake pressure and provided with a first bore having a smaller-diameter portion and a larger-diameter portion extending from the smaller-diameter portion; a second housing provided with a stepped second bore communicating with the first bore to be coupled with the first housing to define a hydraulic pressure chamber, the second housing being connected with the disc brake; a piston arranged in the first bore to be movable forward and backward and provided with an oil channel unit which has two different cross-sectional areas corresponding to the smaller-diameter portion and the larger-diameter portion and is penetrated in a longitudinal direction; and a valve assembly adapted to open and close the oil channel unit of the piston according to the hydraulic brake pressure, wherein, when braking is performed, the piston applies pressure to the hydraulic pressure chamber through a portion of the piston having the cross-sectional area corresponding to the larger-diameter portion among the two different cross-sectional areas to supply hydraulic pressure to the disc brake, wherein the oil channel unit includes a high-pressure hydraulic channel formed at a center of the piston, and a return channel spaced apart from the hydraulic channel, the return channel communicating with the hydraulic pressure chamber.