Hybrid construction machine

• US 8,806,860 B2
• Filed: 07/02/2010
• Issued: 08/19/2014
• Est. Priority Date: 07/10/2009
• Status: Expired due to Fees

• Current Assignee: KYB Corp.
• Original Assignee: Kayaba Industry Company Limited
• Inventors: Kawasaki, Haruhiko, Egawa, Masahiro
• Primary Examiner(s): LESLIE, MICHAEL S
• Application Number:
  US13/143,756
• Publication Number:
  US 20110271669A1
• Time in Patent Office: 1,509 Days
• Field of Search: 604/14, 251/30.01, 251/63.5, 251/282
• US Class Current: 60/414
• CPC Class Codes: E02F 9/2075 of the hybrid type for vehicles in general B60W20/00
• CPC Class Codes: E02F 9/2217 with energy recovery arrangements, e.g. using accumulators, flywheels
• CPC Class Codes: E02F 9/2228 including an electronic controller
• CPC Class Codes: E02F 9/2285 Pilot-operated systems
• CPC Class Codes: E02F 9/2292 Systems with two or more pumps
• CPC Class Codes: E02F 9/2296 Systems with a variable displacement pump
• CPC Class Codes: F15B 13/0402 for linearly sliding valves, e.g. spool valves
• CPC Class Codes: F15B 13/0405 for seat valves, i.e. poppet valves
• CPC Class Codes: F15B 13/0433 the pilot valves being pressure control valves F15B13/0435, F15B13/0436, F15B13/0438 take precedence
• CPC Class Codes: F15B 13/0435 the pilot valves being sliding valves

Abstract

A hybrid construction machine includes a control valve provided in a flow passage that connects an actuator to a regenerative hydraulic motor, an opening of which is controlled by a pilot pressure led to a pilot chamber thereof; and a solenoid pilot control valve that leads a pressure on an upstream side of the control valve to the pilot chamber. In the control valve, a pressure receiving area of a main spool for receiving the pilot pressure is equal to an area obtained by subtracting a pressure receiving area of the main spool for receiving a pressure of an outflow port in a direction for moving the main spool against a biasing force of a biasing member from a pressure receiving area of the main spool for receiving a pressure of the outflow port in a direction for moving the main spool against the pilot pressure.

Claims

1. A hybrid construction machine that performs regeneration using a working oil discharged from an actuator, comprising:

a regenerative hydraulic motor rotated by the working oil discharged from the actuator;

a power generator connected to the hydraulic motor;

a control valve provided in a flow passage that connects the actuator to the hydraulic motor, an opening of which is controlled by a pilot pressure led to a pilot chamber thereof; and

a solenoid pilot control valve that leads a pressure on an upstream side of the control valve to the pilot chamber of the control valve as the pilot pressure,

wherein the control valve comprises;

a main spool that is incorporated to be free to slide into a valve main body such that one end thereof faces the pilot chamber and switches an inflow port and an outflow port between a blocked state and a communicating state; and

a biasing member that is housed in a spring chamber faced by the other end of the main spool and biases the main spool against the pilot pressure of the pilot chamber, and

a pressure receiving area of the main spool for receiving the pilot pressure of the pilot chamber is equal to an area obtained by subtracting a pressure receiving area of the main spool for receiving a pressure of the outflow port in a direction for moving the main spool against the biasing force of the biasing member from a pressure receiving area of the main spool for receiving a pressure of the outflow port in a direction for moving the main spool against the pilot pressure of the pilot chamber.

2. The hybrid construction machine as defined in claim 1, wherein the main spool is divided into a spool main body that faces the spring chamber and a piston portion that is incorporated to be free to slide into the spool main body so as to face the pilot chamber, and

a pressure receiving area of the piston portion for receiving the pilot pressure of the pilot chamber is smaller than a minimum diameter portion of the spool main body.

3. The hybrid construction machine as defined in claim 1, wherein the solenoid pilot control valve is incorporated into the valve main body.