Article transport vehicle

Patent metadata

Field	Value
Publication number	US-12459788-B2
Application number	US-202318102455-A
Country	US
Kind code	B2
Filing date	Jan 27, 2023
Priority date	Jan 28, 2022
Publication date	Nov 4, 2025
Grant date	Nov 4, 2025

Abstract

An article transport vehicle includes a travel section, a holding section, an elevating device, an inclination detection device, an inclination adjustment device, and an inclination control device for controlling the inclination adjustment device. The inclination adjustment device is configured to act on a target belt among a plurality of suspension belts to adjust an inclination of the holding section by adjusting a suspension height at which the holding section is held by the target belt. During the lowering of the holding section to the transfer position by the elevating device, the inclination control device executes an adjustment operation during lowering, in which the inclination of the holding section is detected by the inclination detection device, and based on the result of the detection performed by the inclination detection device, the inclination adjustment device is controlled to adjust the inclination of the holding section.

First claim

What is claimed is:

1 . An article transport vehicle configured to transport an article, the article transport vehicle comprising:
a travel section configured to travel along a travel route; a holding section configured to hold the article; an elevating device configured to raise the holding section to a travel position for traveling along the travel route and lower the holding section to a transfer position for transferring the article between a transfer target location and the holding section, by winding and unwinding a plurality of suspension belts while the holding section is suspended by the plurality of suspension belts; an inclination detection device configured to detect inclination of the holding section with respect to a horizontal plane; an inclination adjustment device configured to adjust the inclination of the holding section; and an inclination control device configured to control the inclination adjustment device; and an elevation control device configured to control the elevating device, wherein the inclination adjustment device is configured to adjust the inclination of the holding section by acting on at least one target belt among the plurality of suspension belts to adjust a suspension height at which the holding section is suspended by the at least one target belt, and wherein the inclination control device executes an adjustment operation during lowering, in which, during lowering of the holding section to the transfer position by the elevating device, the inclination of the holding section is detected by the inclination detection device, and based on a result of the detection performed by the inclination detection device, the inclination adjustment device is controlled to adjust the inclination of the holding section, and wherein, in the adjustment operation during lowering:
the elevation control device controls the elevating device to lower the holding section at a measurement speed, the measurement speed is a constant speed that is lower than a maximum lowering speed, and the maximum lowering speed is a maximum speed of the holding section during lowering to the transfer position;
the inclination control device controls the inclination detection device to detect the inclination of the holding section a plurality of times in a measurement segment in which the elevation control device controls the elevating device to lower the holding section at the measurement speed.

2 . The article transport vehicle according to claim 1 ,
wherein the elevation control device is configured to execute stepwise deceleration control in which a lowering speed of the holding section during lowering to the transfer position is reduced from the maximum lowering speed to an intermediate lowering speed in a first deceleration segment after a maximum speed segment for lowering at the maximum lowering speed, then the intermediate speed is maintained in an intermediate segment, then the lowering speed is reduced from the intermediate speed to a pre-stop speed in a second deceleration segment, then the pre-stop speed is maintained in a pre-stop segment, and then the holding section is stopped at a suspension height corresponding to the transfer location, and wherein the measurement segment is within the intermediate segment.

3 . The article transport vehicle according to claim 1 ,
wherein the inclination detection device comprises an inclination sensor attached to the holding section.

4 . The article transport vehicle according to claim 3 , wherein:
the inclination sensor is configured to detect an inclination angle about a first detection axis and an inclination angle about a second detection axis orthogonal to the first detection axis, the plurality of suspension belts comprise a first belt, a second belt, and a third belt that are respectively connected to mutually different parts of the holding section, the at least one target belt comprises the first belt and the second belt, and wherein with: a section connecting the first belt and the holding section being a first connection section, a section connecting the second belt and the holding section being a second connection section, and a section connecting the third belt and the holding section being a third connection section, and a virtual line connecting the first connection section and the third connection section being a first virtual line, and a virtual line that passes through the second connection section and is orthogonal to the first virtual line being a second virtual line, then: the inclination sensor is oriented in such a manner that either the first detection axis or the second detection axis coincides with the second virtual line in a view in a vertical direction.

5 . The article transport vehicle according to claim 4 ,
wherein the inclination sensor is oriented to coincide with at least one of the first detection axis and the second detection axis in a view in a vertical direction.

6 . The article transport vehicle according to claim 1 , further comprising
an elevation detection device configured to detect whether or not the holding section is being lowered to the transfer location, and wherein the elevation detection device, the inclination detection device, the inclination adjustment device, and the inclination control device are mounted on the holding section.

7 . The article transport vehicle according to claim 1 ,
wherein the elevating device comprises:
a plurality of winding pulleys around which the plurality of suspension belts are respectively wound; and
a winding driving section configured to drive the plurality of winding pulleys to rotate, and
wherein the elevating device is configured to lower the holding section by unwinding the suspension belts from the plurality of winding pulleys and raise the holding section by winding the suspension belts around the winding pulleys, and wherein the inclination adjustment device comprises at least one of: an adjustment winding device that is provided separately from the winding pulleys and is configured to wind and unwind the at least one target belt, an adjustment pulley driving device comprising:
an adjustment pulley that is provided separately from the winding pulleys and is arranged in such a manner as to come into contact with the at least one target belt; and
an adjustment driving section configured to change a position of the adjustment pulley in a pushing direction with respect to the at least one target belt, or
an adjustment cam driving device comprising:
a cam member configured to change a distance in at least a vertical direction between the holding section and the at least one target belt by being driven to rotate; and
a cam rotation driving section configured to drive the cam member to rotate.

8 . The article transport vehicle according to claim 1 ,
wherein, in the adjustment operation during lowering:
the inclination control device receives results of the detection performed a plurality of times in the measurement segment; and
based on the results of the detection performed a plurality of times in the measurement segment, the inclination control device controls the inclination adjustment device to adjust the inclination of the holding section while the elevation control device controls the elevating device to lower the holding section.

9 . The article transport vehicle according to claim 1 ,
wherein, in the adjustment operation during lowering:
the inclination control device receives results of the detection performed a plurality of times in the measurement segment; and
based on the results of the detection performed a plurality of times in the measurement segment, the inclination control device controls the inclination ad

Assignees

• Daifuku Kk

Inventors

• Kinugawa Tomotaka
• Otsuka Hiroshi
• Shiroishi Keisuke
• Kawaguchi Koji
• Morikawa Yasushi

Classifications

• H10P72/3221 Primary

  Overhead conveying · CPC title

• H10P72/3206

  the substrate being handled substantially vertically · CPC title

• H10P72/3202

  Mechanical details, e.g. rollers or belts · CPC title

• H10P72/3222

  Loading to or unloading from a conveyor · CPC title

• H10P72/3218

  Conveying cassettes, containers or carriers · CPC title