JP2005207065A5 - - Google Patents

Claims (6)

A traveling body, a revolving body, and a front working machine, the revolving body includes a revolving frame and a cab, and an operation lever and a driver's seat for operating the front working machine and the revolving body are disposed on the cab In a safety device for a construction machine having a structure that supports the cab so that it can tilt forward with respect to the swivel frame, and the cab can be tilted up,
When the cab is tilted up, operation restriction means for prohibiting the operation of the front work machine ;
A safety device for a construction machine, comprising: a prohibition canceling unit that cancels a prohibition state of the operation of the front work machine by the operation restricting unit by manual operation when the cab is tilted up . The safety device for a construction machine according to claim 1,
The construction machine supplies a main hydraulic pump, a plurality of hydraulic actuators driven by pressure oil discharged from the hydraulic pump to drive the front work machine and the swing body, and a supply from the main hydraulic pump to the plurality of hydraulic actuators. A plurality of control valves for controlling the flow of pressure oil, a pilot pump, and the operation lever, and generating a pilot secondary pressure using the discharge pressure of the pilot pump as a pilot primary pressure, the pilot operated control An operation lever device for switching a valve,
The operation restricting means is provided in a pilot primary pressure line that guides the pilot primary pressure from the pilot pump to the operation lever device, and an electromagnetic valve that switches communication / cutoff of the pilot primary pressure line, and the cab tilts up. And a switching control means for switching the solenoid valve from the communication position to the shut-off position when it is operated. The safety device for a construction machine according to claim 2 ,
The construction machine further includes a gate lock lever arranged in the cab, and the electromagnetic valve is an electromagnetic valve that is switched by the gate lock lever. The safety device for a construction machine according to claim 1,
The construction machine includes a main hydraulic pump, a plurality of hydraulic actuators that are driven by pressure oil discharged from the hydraulic pump to drive the front working machine, and an engine that drives the main hydraulic pump,
The safety device for a construction machine, wherein the operation restricting means is fuel supply stopping means for stopping supply of fuel to the engine when the cab is tilted up. The safety device for a construction machine according to claim 1,
The operation restricting means operates when a current is supplied from the power supply and the power supply, and the electromagnetic switching means for disabling the front work machine, and the supply of current from the power supply to the electromagnetic switching means can be cut off. A first position that is closed when the cab is tilted down, a second position that is open when the cab is tilted up, and a second position of the switch means. A safety device for a construction machine, having a third position that is closed by manual operation when the position is maintained, and maintains the state. The safety device for a construction machine according to claim 1,
The operation restricting means operates when a current is supplied from the power source, and an electromagnetic switching means for disabling the front work machine, and a supply of current from the power source to the electromagnetic switching means can be cut off. The switch means includes first and second switches connected in series, and a relay connected in parallel to the first and second switches, the first and second switches. The second switch is a switch in which the first switch is closed and the second switch is opened when the cab is tilted down, the first switch is closed and the second switch is opened when the cab is tilted up. Yes, the relay is turned on when the first switch is closed, and once turned on while the second switch is closed, then the relay is kept on even if the first switch is opened. When the cab tilts up, the first and second switches are switched in the order of the first switch and the second switch, and when the cab tilts down, the first and second switches A safety device for a construction machine, which is arranged so as to be switched in the order of one switch and second switch.