Transporting apparatus having vertically movable holding portion

• US 7,255,238 B2
• Filed: 07/14/2004
• Issued: 08/14/2007
• Est. Priority Date: 07/18/2003
• Status: Active Grant

• Current Assignee: Daifuku Company Limited
• Original Assignee: Daifuku Company Limited
• Inventors: Ikeya, Masayuki
• Primary Examiner(s): Brahan; Thomas J.
• Application Number:
  US10/890,713
• Publication Number:
  US 20050011851A1
• Time in Patent Office: 1,126 Days
• Field of Search: 294/907, 901/46, 901/47, 212/281, 212/331
• US Class Current: 212/331
• CPC Class Codes: B66C 1/28 Duplicate, e.g. pivoted, members engaging the loads from two sides
• CPC Class Codes: B66C 13/085 electrical
• CPC Class Codes: B66C 13/48 Automatic control of crane drives for producing a single or repeated working cycle; Programme control
• CPC Class Codes: Y10S 294/907 Sensor controlled device

Abstract

The present invention provides a transporting apparatus provided with a sensor for detecting information relating to a relative position in the vertical direction between an article to be transported and a holding portion for holding the article, and a controller that is linked to this sensor through signals, wherein the controller raises the holding portion by a set raising amount when the sensor detects that the holding portion is below a target lowering position. Thus, it is possible to provide a transporting apparatus with which the position of the holding portion can be automatically moved to a suitable position even if the holding portion is lowered too far with respect to the article.

Claims

1. A transporting apparatus comprising:

a traveling carriage;

a holding portion for holding an article, the holding portion being capable of switching between a holding state and a hold release state and being supported to the traveling carriage so as to be raised and lowered with respect to the traveling carriage by a raising and lowering motor;

a raised/lowered amount detection sensor for detecting an amount that the holding portion has been raised or lowered by the raising and lowering motor;

an excess lowering detection sensor for detecting an excess lowering state where the holding portion has been lowered too far below a target lowering position that is an appropriate position for holding the article by detecting a relative vertical positional relationship between the holding portion and the article placed on an article station, and that is to be held by the holding portion;

a controller linked by signals to the raised/lowered amount detection sensor and the excess lowering detection sensor, wherein the controller controls operation of the raising and lowering motor and switching of the holding portion, with the traveling carriage stopped at a target position for article transfer, so as to raise and lower the holding portion and to retrieve an article loaded on an article station and release an article to the article station, and operates the raising and lowering motor to lowering to the target lowering position based on detection information from the raised/lowered amount detection sensor; and

a detected member extending downwardly beyond a lower surface of the holding portion to contact the article to be held by the holding portion, wherein the excess lowering detection sensor is adapted to detect the detected member;

wherein when the holding portion is lowered to the target lowering position, the controller performs a raising correction process of raising the holding portion by a set raising amount if the excess lowered state has been detected by the excess lowering detection sensor, and

wherein the controller repeatedly executes the raising correction process as long as the excess lowering detection sensor detects the excess lowering state unless a set number of corrections has been reached, and when the excess lowering state continues to be detected by the excess lowering detection sensor even after that set number of corrections has been performed, the controller determines that an abnormality has occurred.

2. The transporting apparatus according to claim 1,

wherein the holding portion has at least a pair of chucks adapted to hold a flange spaced apart from an upper surface of the article to be held and having a smaller dimension in a fore-and-aft direction than the fore-and-aft dimension of the article and a smaller dimension in a lateral direction, that is perpendicular to the fore-and-aft direction, than the lateral dimension of the article, and

wherein the at least a pair of chucks are located on the holding portion at positions such that the chucks are capable of moving in a space between the upper surface of the article and a lower surface of the flange.

3. The transporting apparatus according to claim 1,

wherein the detected member has a first portion that is adapted to abut against the article to be held by the holding portion and a second portion that is sensed by the excess lowering detection sensor;

and

wherein the detected member has a first position in which the first portion is not in contact with the article to be held by the holding portion, a second position in which the first portion is in contact with the article to held by the holding portion with the holding portion in the appropriate position to hold the article, and a third position in which the first portion is in contact with the article to be held by the holding portion with the holding portion lowered beyond the appropriate position to hold the article.

4. A transporting apparatus comprising:

a traveling carriage;

a holding portion for holding an article, the holding portion being capable of switching between a holding state and a hold release state and being supported to the traveling carriage so as to be raised and lowered with respect to the traveling carriage by a raising and lowering motor;

a raised/lowered amount detection sensor for detecting an amount that the holding portion has been raised or lowered by the raising and lowering motor;

an excess lowering detection sensor for detecting an excess lowering state where the holding portion has been lowered too far below a target lowering position that is an appropriate position for holding the article by detecting a relative vertical positional relationship between the holding portion and the article placed on an article station, and that is to be held by the holding portion;

a controller linked by signals to the raised/lowered amount detection sensor and the excess lowering detection sensor, wherein the controller controls operation of the raising and lowering motor and switching of the holding portion, with the traveling carriage stopped at a target position for article transfer, so as to raise and lower the holding portion and to retrieve an article loaded on an article station and release an article to the article station, and operates the raising and lowering motor to lowering to the target lowering position based on detection information from the raised/lowered amount detection sensor;

a suitable lowered state detection sensor for detecting that the holding portion is in a suitable lowered state where the holding portion is positioned at or within a suitable range near the target lowering position by detecting the relative vertical positional relationship between the holding portion lowered to the target lowering position and an article loaded on the article station; and

a hold release confirmation detection sensor for detecting whether a holding state in which the holding portion is holding an article loaded on the article station is a suitable holding state for switching the holding portion to a hold release state;

wherein when the holding portion is lowered to the target lowering position, the controller performs a raising correction process of raising the holding portion by a set raising amount if the excess lowered state has been detected by the excess lowering detection sensor,

wherein the controller determines that an abnormality has occurred when in the retrieval operation and the release operation the excess lowering detection sensor does not detect an excess lowering state and the suitable lowered state detection sensor does not detect a suitable lowered state, and

wherein the controller performs a lowering correction process for release in which the holding portion is lowered by a set lowering amount when, in the release operation, the excess lowering detection sensor does not detect excess lowering and the suitable lowered state detection sensor detects a suitable lowered state, and the hold release confirmation detection sensor does not detect a suitable holding state for release.

5. The transporting apparatus according to claim 4, further comprising:

a detected member extending downwardly beyond a lower surface of the holding portion to contact the article to be held by the holding portion, wherein the excess lowering detection sensor is adapted to detect the detected member, and

wherein the controller repeatedly executes the lowering correction process for release until a set number of corrections has been reached as long as the suitable holding state is not detected by the hold release confirmation detection sensor, and when a suitable holding state for release is not detected by the hold release confirmation detection sensor even after a set number of corrections has been performed, the controller determines that an abnormality has occurred.

6. The transporting apparatus according to claim 4,

wherein the holding portion has at least a pair of chucks adapted to hold a flange spaced apart from an upper surface of the article to be held and having a smaller dimension in a fore-and-aft direction than the fore-and-aft dimension of the article and a smaller dimension in a lateral direction, that is perpendicular to the fore-and-aft direction, than the lateral dimension of the article, and

wherein the at least a pair of chucks are located on the holding portion at positions such that the chucks are capable of moving in a space between the upper surface of the article and a lower surface of the flange.

7. A transporting apparatus comprising:

a traveling carriage;

a holding portion for holding an article, the holding portion being capable of switching between a holding state and a hold release state and being supported to the traveling carriage so as to be raised and lowered with respect to the traveling carriage by a raising and lowering motor;

a raised/lowered amount detection sensor for detecting an amount that the holding portion has been raised or lowered by the raising and lowering motor;

an excess lowering detection sensor for detecting an excess lowering state where the holding portion has been lowered too far below a target lowering position that is an appropriate position for holding the article by detecting a relative vertical positional relationship between the holding portion and the article placed on an article station, and that is to be held by the holding portion;

a controller linked by signals to the raised/lowered amount detection sensor and the excess lowering detection sensor, wherein the controller controls operation of the raising and lowering motor and switching of the holding portion, with the traveling carriage stopped at a target position for article transfer, so as to raise and lower the holding portion and to retrieve an article loaded on an article station and release an article to the article station, and operates the raising and lowering motor to lowering to the target lowering position based on detection information from the raised/lowered amount detection sensor;

a suitable lowered state detection sensor for detecting that the holding portion is in a suitable lowered state where the holding portion is positioned at or within a suitable range near the target lowering position by detecting the relative vertical positional relationship between the holding portion lowered to the target lowering position and an article loaded on the article station; and

a holding state detection sensor for detecting whether, in the retrieval operation, a holding state, in which the holding portion is holding an article loaded on the article station, is a suitable holding state in which the article is suitably held;

wherein when the holding portion is lowered to the target lowering position, the controller performs a raising correction process of raising the holding portion by a set raising amount if the excess lowered state has been detected by the excess lowering detection sensor,

wherein the controller determines that an abnormality has occurred when in the retrieval operation and the release operation the excess lowering detection sensor does not detect an excess lowering state and the suitable lowered state detection sensor does not detect a suitable lowered state, and

wherein the controller, in the retrieval operation, switches the holding portion to a holding state when the excess lowering detection sensor does not detect excess lowering and the suitable lowered state detection sensor detects a suitable lowered state, and when, due to this switching, the holding state detection sensor does not detect a suitable holding state, the controller executes a lowering correction process for retrieval in which the holding portion is lowered by a set lowering amount.

8. The transporting apparatus according to claim 7, further comprising:

a detected member extending downwardly beyond a lower surface of the holding portion to contact the article to be held by the holding portion, wherein the excess lowering detection sensor is adapted to detect the detected member, and

wherein the controller repeatedly executes the lowering correction process for retrieval until a set number of corrections has been reached as long as the holding state detection sensor does not detect a suitable holding state, and when the holding state detection sensor does not detect a suitable holding state even after a set number of corrections has been performed, the controller determines that an abnormality has occurred.

9. The transporting apparatus according to claim 7,

wherein the holding portion has at least a pair of chucks adapted to hold a flange spaced apart from an upper surface of the article to be held and having a smaller dimension in a fore-and-aft direction than the fore-and-aft dimension of the article and a smaller dimension in a lateral direction, that is perpendicular to the fore-and-aft direction, than the lateral dimension of the article, and

wherein the at least a pair of chucks are located on the holding portion at positions such that the chucks are capable of moving in a space between the upper surface of the article and a lower surface of the flange.

10. A transporting apparatus comprising:

a traveling carriage;

a holding portion for holding an article, the holding portion being capable of switching between a holding state and a hold release state, and being supported to the traveling carriage such that the holding portion can be raised and lowered with respect to the traveling carriage by a raising and lowering motor;

a first sensor operatively linked to the raising and lowering motor, for detecting an amount that the holding portion has been raised or lowered with respect to the traveling carriage;

a second sensor for detecting information relating to a relative position in the vertical direction between the holding portion and the article to be held by the holding portion and for outputting a first signal indicative of the fact that the holding portion is lowered beyond an appropriate position to hold the article to be held by the holding portion;

a controller that is signally connected to the first sensor and the second sensor, wherein the controller raises the holding portion by a set raising amount in response to the first signal from the second sensor detecting that the holding portion is below a target lowering position that is the appropriate position for holding the article; and

a detected member movable with respect to the holding portion and having a first portion that abuts against the article to be held by the holding portion and a second portion that is sensed by the second sensor;

wherein the detected member has a first position in which the first portion is not in contact with the article to be held by the holding portion, a second position in which the first portion is in contact with the article to held by the holding portion with the holding portion in the appropriate position to hold the article, and a third position in which the first portion is in contact with the article to be held by the holding portion with the holding portion lowered beyond the appropriate position to hold the article, and

wherein the second sensor outputs the first signal in response to a sensing of the second portion of the detected member.

11. The transporting apparatus according to claim 10, further comprising:

a third sensor disposed at a position lower than the second sensor, wherein the third sensor outputs a second signal indicative of the fact that the holding portion is in the appropriate position for holding the article by sensing the second portion of the detected member.

12. The transporting apparatus according to claim 10, further comprising:

a pair of chucks that are provided in the holding portion and that are for holding the article, wherein each chuck is provided with a sensor that abuts against the article.

13. The transporting apparatus according to claim 10,

wherein the holding portion has at least a pair of chucks adapted to hold a flange spaced apart from an upper surface of the article to be held and having a smaller dimension in a fore-and-aft direction than the fore-and-aft dimension of the article and a smaller dimension in a lateral direction, that is perpendicular to the fore-and-aft direction, than the lateral dimension of the article, and

wherein the at least a pair of chucks are located on the holding portion at positions such that the chucks are capable of moving in a space between the upper surface of the article and a lower surface of the flange.