Patent ID: 6050091
Filing Date: 2000-04-18
Classification: E02F

Abstract:
A braking apparatus for a hydraulic motor, comprising:a rotary side friction plate coupled to a rotary component of the hydraulic motor;a fixed side friction plate coupled to a fixed component of the hydraulic motor;a braking cylinder assembly having a piston, a piston pressure receiving chamber and a spring, wherein said piston is adapted to be energized by said spring to move in a braking direction for bringing said fixed side friction plate and said rotary side friction plate into a pressure contact, and said piston pressure receiving chamber is adapted to be supplied with pressure fluid to displace said piston in a braking release direction too separate said fixed side friction plate and said rotary side friction plate from each other;an operating valve for supplying pressure fluid into said hydraulic motor;a hydraulic pilot valve for providing pilot pressure fluid for use to switch said operating valve;a hydraulic circuit for delivering pilot pressure fluid from said hydraulic pilot valve into said piston pressure receiving chamber; anda fluid flow control valve in said hydraulic circuit and having an area of valve opening progressively reduced as a function of a distance of travel of said piston moving and displaced from a braking position towards a braking release position.