Patent ID: 8548693

Claim:
A control device for a working mechanism of a construction vehicle for controlling the cylinder length of a predetermined hydraulic cylinder that is used in the working mechanism of the construction vehicle, comprising: a cylinder length detection unit configured to determine the cylinder length of said predetermined hydraulic cylinder; and a cylinder length control unit configured to control the cylinder length of said predetermined hydraulic cylinder; wherein said cylinder length control unit is configured to: (A) in a first region, perform feedback control of the cylinder length by supplying hydraulic fluid to said predetermined hydraulic cylinder on the basis of a control characteristic that is set in advance and the cylinder length determined by said cylinder length detection unit, said first region extending from input of a start command that initiates control of said cylinder length until said cylinder length arrives at a set value that is set before a target value, wherein said control characteristic includes a first control characteristic that is used if the cylinder length at the start of control is less than or equal to a control threshold value and a second control characteristic that is used if the cylinder length at the start of control is greater than said control threshold value; and (B) in a second region, perform open loop control of the cylinder length by supplying hydraulic fluid to said predetermined hydraulic cylinder while decreasing the control signal at a predetermined rate, said second region ranging from said set value until said cylinder length arrives at said target value, wherein said predetermined rate includes a first rate that corresponds to said first control characteristic and a second rate that corresponds to said second control characteristic; and said first rate is used is used if said first control characteristic was used in said first region, and said second rate is used, if said second control characteristic was used in said first region.