Patent ID: 6612109
Filing Date: 2003-09-02
Classification: E02F,F15B

Abstract:
A hydraulic system for a backhoe, comprising:a first hydraulic fluid source configured to generate a flow of hydraulic fluid at a first pressure; a second hydraulic fluid source configured to generate a flow of hydraulic fluid at a second pressure higher than the first pressure; a hydraulic fluid reservoir; at least one boom swing cylinder, a boom lift cylinder, a dipper cylinder, and a bucket cylinder; a valve array including a boom swing cylinder valve, a boom lift cylinder valve, a dipper cylinder valve, and a bucket cylinder valve, in fluid communication with the at least one boom swing cylinder, the boom lift cylinder, the dipper cylinder, and the bucket cylinder, wherein each of the valves in the valve array are in fluid communication with the first fluid source and are disposed to regulate a flow of fluid from the first fluid source to their respective cylinders, and wherein the second fluid source is coupled to the boom lift cylinder while bypassing the remainder of the valves in the valve array, and a pressure boost valve in fluid communication with the boom lift cylinder and the second fluid source and configured to provide fluid flow from the second fluid source to the boom lift cylinder when the boom lift cylinder valve is opened.