US 12,241,548 B2
Obstacle detector of construction vehicle
Ryohei Endo, Saitama (JP); Norio Morioka, Saitama (JP); Masato Ohgiya, Saitama (JP); and Nobumasa Motokawa, Saitama (JP)
Assigned to Sakai Heavy Industries, Ltd., Tokyo (JP)
Filed by SAKAI HEAVY INDUSTRIES, LTD., Tokyo (JP)
Filed on Jun. 30, 2021, as Appl. No. 17/364,827.
Claims priority of application No. 2020-112360 (JP), filed on Jun. 30, 2020.
Prior Publication US 2021/0404553 A1, Dec. 30, 2021
Int. Cl. F16H 61/433 (2010.01); B60T 7/22 (2006.01); E01C 19/26 (2006.01); F15B 15/24 (2006.01)
CPC F16H 61/433 (2013.01) [B60T 7/22 (2013.01); E01C 19/26 (2013.01); F15B 15/24 (2013.01)] 6 Claims
OG exemplary drawing
 
1. 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.