Brake Apparatus

Abstract

A brake apparatus includes a master cylinder, a hydraulic source, a reservoir tank, a fluid pool, a fluid level detection unit, and an electronic control unit. The electronic control unit is configured to switch brake control according to the fluid level detected by the fluid level detection unit. The brake fluid is transmitted from the first chamber to the wheel cylinder with use of the master cylinder to increase a pressure in the wheel cylinder. The brake fluid in the second chamber is transmitted to the wheel cylinder with use of the hydraulic source to increase a pressure in the wheel cylinder.

1 . A brake apparatus comprising:
 a master cylinder configured to be activated according to a brake operation performed by a driver;   a hydraulic source configured to introduce brake fluid and supply the brake fluid to a wheel cylinder;   a reservoir tank divided into a first chamber connected to a wheel cylinder via the master cylinder and a second chamber connected to an intake-side of the hydraulic source;   a fluid pool having a predetermined volume and provided between the second chamber and the intake-side of the hydraulic source;   a fluid level detection unit configured to detect a fluid level of the brake fluid in the reservoir tank; and   an electronic control unit configured to switch brake control according to the fluid level detected by the fluid level detection unit between first brake control of transmitting the brake fluid from the first chamber to the wheel cylinder with use of the master cylinder to increase a pressure in the wheel cylinder, and second brake control of transmitting the brake fluid in the second chamber to the wheel cylinder with use of the hydraulic source to increase a pressure in the wheel cylinder.   
     
     
         2 . The brake apparatus according to  claim 1 , wherein the second chamber is connected to the intake-side of the hydraulic source via the fluid pool, and
 wherein the hydraulic source is configured to introduce the brake fluid in the second chamber via the fluid pool.   
     
     
         3 . The brake apparatus according to  claim 1 , wherein the hydraulic source is a pump. 
     
     
         4 . The brake apparatus according to  claim 1 , wherein the first chamber is further divided into two chambers,
 wherein the wheel cylinder includes a plurality of wheel cylinders, and   wherein the two chambers are respectively connected, via the master cylinder, to a primary system oil passage, which supplies the pressure to a first wheel cylinder of the plurality of wheel cylinders, and a secondary system oil passage, which supplies the pressure to a second wheel cylinder of the plurality of wheel cylinders.   
     
     
         5 . The brake apparatus according to  claim 1 , wherein the fluid level detection unit detects the fluid level in the second chamber