Obstacle detector of construction vehicle

An obstacle detector of a construction vehicle comprising:

• a controller including a determinator for determining presence or absence of an obstacle based on data from a sensor;
• and
• a brake mechanism for causing the construction vehicle to activate an emergency brake after the determinator has detected the obstacle,
• wherein the brake mechanism includes:
• a first hydraulic closed circuit in which a pump for rolling, which is equipped with a swash plate and is driven by an engine, is connected in series to a motor for rolling, which causes the construction vehicle to roll;
• a second hydraulic closed circuit including a first hydraulic passage communicating with one side of the pump for rolling and a second hydraulic passage communicating with another side of the pump for rolling, to actuate the swash plate;
• and
• a neutral valve provided in the second closed circuit and communicating the one side of the pump with the another side of the pump for rolling,
• wherein, when the emergency brake is activated, at least one of a compressive returning force is generated compressing a low-pressure side of the swash plate from a tilt position to a neutral position and a decompressive returning force is generated decompressing a high-pressure side of the swash plate so as to return the swash plate to the neutral position,
• wherein a compression-side switching valve is switched to supply hydraulic oil to the low-pressure side of the swash plate so as to generate the compressive returning force,
• wherein a decompression-side switching valve is switched to return the hydraulic oil in the high-pressure side of the swash plate to a hydraulic tank so as to generate the decompressive returning force, and
• wherein the controller individually controls switching timings of the neutral valve, the compression-side switching valve, and the decompression-side switching valve.