Kabushiki Kaisha Toyota Jidoshokki

Southwest Research Institute

Nishina Industrial Co., Ltd.

Nishia Industrial Co., Ltd.

Yuki Ueda

Tsutomu Matsuo

Takashi Uno

Naoya Yokomachi

Hirohiko Ishikawa

Tetsuya Goto

Junichi Morita

Toshinari Fukatsu

Shigeto Nakajima

Takanori Kanna

Yukinori Takeda

Koichi Kinoshita

Ryo Yazawa

Joseph A Auchter

Koshiro Saji

Akira Nakajo

Tsutomo Matsuo

Daniel D'Souza

An autonomous vehicle includes first and second road surface image obtaining devices that are located on a bottom surface of the vehicle body and obtain images of a road surface below the vehicle body, respectively. The autonomous vehicle also includes a memory unit that stores a map image of the road surface, the map image being associated with geographical location information. The autonomous vehicle further includes first and second self-location estimating units that each compare a feature extracted from the image of the road surface obtained by corresponding one of the first and second road surface image obtaining devices with a feature extracted from the map image, thereby estimating a self-location of the autonomous vehicle.

Autonomous vehicle and self-location estimating method in autonomous vehicle

A hydraulic drive device for an industrial vehicle includes a variable displacement pump, a displacement control valve, a power steering cylinder, a power steering valve, a loading cylinder, a loading valve, a hydraulic oil passage, and a pilot line. The displacement control valve controls the variable displacement pump to increase displacement of the variable displacement pump when differential pressure between discharge pressure of hydraulic oil discharged from the variable displacement pump and pilot pressure generated in the pilot line is smaller than a predetermined set pressure. A spool of the loading valve is provided with a groove portion that forms a communication passage that makes communication between the hydraulic oil passage and the pilot line at a neutral position of the loading valve when the power steering valve is located in a neutral position.

Hydraulic drive device for industrial vehicle

Provided is a variable displacement pump which sucks and discharges a working fluid by moving a piston with a stroke in response to an inclination angle of a swash plate, the variable displacement pump including: a control piston which includes a columnar piston portion pressing the swash plate and adjusts the inclination angle of the swash plate between a maximal inclination angle in which a discharge capacity of the working fluid becomes maximal and a minimal inclination angle in which the discharge capacity of the working fluid becomes minimal; a piston accommodation portion which is formed in the housing and accommodates the piston portion; and a pressed portion which is disposed between the swash plate and the piston portion and is pressed toward the swash plate by the piston portion, in which when the inclination angle of the swash plate is an intermediate inclination angle in which the discharge capacity of the working fluid becomes an intermediate amount between the maximal amount and the minimal amount, a contact point between the piston portion and the pressed portion is located at a center portion including an axis center of the piston portion in an end surface on the side of the swash plate in the piston portion.

Variable displacement pump

A hydraulic drive device for a cargo vehicle includes a hydraulic cylinder supplying and discharging of hydraulic oil, an operation member that operates the hydraulic cylinder, a hydraulic pump, a lowering oil path connecting the hydraulic cylinder and the hydraulic pump, an operation valve disposed in the lowering oil path, a bypass oil path that branches off from the lowering oil path, a bypass flow rate control valve disposed in the bypass oil path and that controls a bypass flow rate, and a resistance element that is disposed closer to the hydraulic cylinder than the operation valve in the lowering oil path and that increases a fluid resistance. A pilot flow path of the bypass flow rate control valve is connected to a part of the lowering oil path between the hydraulic cylinder and the resistance element.

Hydraulic drive device for cargo vehicle

A hydraulic driving device of an industrial vehicle includes: a tank which stores hydraulic oil; a hydraulic pump which includes a suction port sucking the hydraulic oil and a discharge port discharging the hydraulic oil; a hydraulic cylinder which is driven by the hydraulic oil discharged from the discharge port of the hydraulic pump; a direction switching valve which is disposed among the hydraulic pump, the tank, and the hydraulic cylinder and switches a hydraulic oil flow direction in response to an operation state of operation means for driving the hydraulic cylinder; in which the direction switching valve includes a main spool which moves in response to the operation state of the operation means and a flow regulator which is disposed inside the main spool to control a flow rate of the hydraulic oil flowing from the hydraulic cylinder to the tank.

Hydraulic driving device of industrial vehicle

A variable displacement swash plate type piston pump includes first and second housing members fastened to each other by fastening members, a rotary shaft, a swash plate. A section of the inner circumferential surface of the first housing member has a recess. A bulging portion is arranged in a section of the outer circumferential wall of the first housing member. A section of the outer circumferential wall of the second housing member has a closing portion that closes the opening of the recess. The fastening members include first and second fastening members arranged at positions that are on the opposite sides of the recess, inside the width of the swash plate in a direction along the inclination axis of the swash plate, and closer to the rotary shaft than the distal ends of the bulging portion and the closing portion in the bulging direction.

Variable displacement swash plate type piston pump

Provided is a variable displacement pump which includes a cylinder block including a plurality of cylinder bores formed in a rotation shaft in a circumferential direction and rotating together with the rotation shaft, a piston provided inside each of the plurality of cylinder bores to be slidable, and a swash plate supported to be tiltable with respect to the rotation shaft while a distal end portion of the piston is slidable thereon and which sucks and discharges a working fluid by moving the piston in a reciprocating manner with a stroke in accordance with an inclination angle of the swash plate, the variable displacement pump including: a control piston which includes a piston portion pressing the swash plate and controls the inclination angle of the swash plate; a piston accommodation portion which is formed in the housing and accommodates the piston portion; and a hollow cylindrical guide portion which is disposed between the piston accommodation portion and the piston portion and includes an inner peripheral surface supporting the piston portion to be slidable thereon, in which the housing is formed of a material having higher fatigue strength than the guide portion and the guide portion is formed of a material harder than the housing.

A hydraulic control device of a forklift truck includes a first hydraulic cylinder, a first instructing member, a second hydraulic cylinder, a second instructing member, a hydraulic pump, an electric motor, a first oil passage, a lowering control valve, a second oil passage that is branched from the first oil passage at a junction, a flow control valve, a first pilot passage through which pressure in the first oil passage at a position between the first hydraulic cylinder and the lowering control valve is applied to a first accommodating chamber of the flow control valve as the pressure upstream of the lowering control valve, and a second pilot passage through which pressure in the first oil passage at a position between the lowering control valve and the hydraulic pump is applied to a second accommodating chamber of the flow control valve as the pressure downstream of the lowering control valve.

Hydraulic control device of forklift truck

A hydraulic pump having a rotary shaft rotatably supported with respect to a casing, the hydraulic pump including: a bearing part provided to one end side and the other end side of the rotary shaft; and a first annular member provided around the rotary shaft on at least one side of the one end side and the other end side of the rotary shaft. The bearing part on the one side has a support part which rotatably supports the rotary shaft, and a preload applying member which applies a preload in the axial direction to the support part. The first annular member is interposed between the bearing part of the one side and a receiving part of the rotary shaft in the axial direction, and an inner diameter of the first annular member is larger than a diameter of the rotary shaft.

Hydraulic pump

A hydraulic control device of a forklift truck includes a first hydraulic cylinder, a first instruction member, a second hydraulic cylinder, a second instruction member, a hydraulic pump, an electric motor, a first passage which has a drain passage, a lowering control valve that controls flow of hydraulic oil, a flow rate control valve, and a controller. When a lowering operation of forks and an operation of a hydraulically-operated unit are performed simultaneously, when a required rotation speed of the hydraulic pump that is required for operating the hydraulically-operated unit at an instruction speed based on an operation of the second instruction member is a specified rotation speed or lower, the controller controls an instruction rotation speed of the electric motor so as to operate the hydraulic pump at the required rotation speed to thereby restrict the operation of the hydraulic pump.

Hydraulic control device of a forklift truck

A hydraulic control device for a forklift includes: a plurality of hydraulic mechanisms including a lifting/lowering hydraulic cylinder and a tilting hydraulic cylinder; a hydraulic pump; an electric motor; a discharge control mechanism; a proportional valve; a flow rate control valve; and a controller. When the lifting/lowering hydraulic cylinder performs a lowering operation of the fork and a hydraulic mechanism other than the lifting/lowering hydraulic cylinder simultaneously performs a further operation, the controller controls an open degree of the proportional valve in accordance with a rotation speed difference of a required lowering operation rotation speed for the hydraulic pump, which is required to perform the lowering operation at an instructed speed that is in accordance with an operation amount of the lifting/lowering control member, and a required further operation rotation speed for the hydraulic pump, which is required to perform the further operation.

Hydraulic control device for forklift

An electromagnetic switching valve, for which the maximum opening is set to be small, is disposed on piping between a lift cylinder and a hydraulic pump motor. A pilot check valve, for which the maximum opening is set to be larger than the electromagnetic switching valve, is disposed on piping, different from the piping, between the lift cylinder and the hydraulic pump motor. In addition, during lowering operations, first, the electromagnetic switching valve is opened, and then after the same is opened, the pilot check valve is opened after a prescribed time has passed. Thus, the shock generated when lowering an object to be raised/lowered is reduced and a fork is operated quickly.

Lifting device

A hydraulic control device for a forklift includes a hydraulic pump, a single electric motor for driving the hydraulic pump, an outflow control mechanism provided between a lift cylinder and the hydraulic pump, a flow control valve provided between the outflow control mechanism and a draining portion, and a controller. When a lowering operation of a fork and either forward or rearward mast tilting operations of a mast are performed at the same time, the controller controls the electric motor based on a target speed of the hydraulic pump. The flow control valve controls the flow rate of hydraulic fluid from the lift cylinder to the hydraulic pump and the flow rate from the lift cylinder to the draining portion in accordance with the difference between the actual rotation speed of the hydraulic pump and the target rotation speed of the hydraulic pump.

A hydraulic drive device for cargo handling vehicle has: a tank; a pump for drawing in a hydraulic oil from the tank and supplying the hydraulic oil to hydraulic cylinders; an electric motor for driving the pump; a solenoid-controlled proportional valve disposed between an inlet port of the pump and a bottom chamber of an up-and-down hydraulic cylinder and configured to open with a valve travel depending upon a control input of a descent control of an up-and-down control member; a pressure compensation valve disposed between a branch portion located between the pump and the solenoid-controlled proportional valve and the tank and configured to open with a valve travel depending upon a pressure difference between pressures upstream and downstream of the solenoid-controlled proportional valve; and a valve disposed between the pressure compensation valve and the tank and configured to be switched between an open position and a close position.

Hydraulic drive device for cargo handling vehicle

An outlet port of a hydraulic pump/motor and a bottom chamber of a lift cylinder are connected to each other by a hydraulic fluid passage. A hydraulic fluid passage that is connected to a hydraulic fluid tank is formed to branch off the hydraulic fluid passage. A flow control valve controls the hydraulic fluid delivered from the lift cylinder when the fork is lowered, thereby regulating the flow rate of hydraulic fluid supplied to the hydraulic pump/motor and the flow rate of hydraulic fluid supplied to the hydraulic fluid tank. If regenerative operation can be performed, the flow control valve is closed and hydraulic fluid is delivered to the hydraulic pump/motor. If regenerative operation cannot be performed, the flow control valve is opened and hydraulic fluid is delivered to the hydraulic fluid tank. In either case, the fork can be lowered at an instructed speed.

Growing community of inventors

Kariya, Japan

Yuki Ueda