Tool side robotic safety interlock
(19)AUSTRALIAN PATENT OFFICE (54) Title Tool side robotic safety interlock (51)6 International Patent Classification(s) B23Q 003/155 (21) Application No: 2003297516 (22) Application Date: 2003.12.23 (87) WIPO No: WO04/080663 (30) Priority Data (31) Number (32) Date 10/387,279 2003 .03 .12 (33) Country US 200511037 (43) Publication Date : 2004 .09.30 (43) Publication Journal Date : 2004 .11.04 (71) Applicant(s) ATI INDUSTRIAL AUTOMATION (72) Inventor(s) Perry, Dwayne; Heavner, Richard (-1-1) Application NoAU2003297516 A8(19)AUSTRALIAN PATENT OFFICE (54) Title Tool side robotic safety interlock (51)6 International Patent Classification(s) B23Q 003/155 (21) Application No: 2003297516 (22) Application Date: 2003.12.23 (87) WIPO No: WO04/080663 (30) Priority Data (31) Number (32) Date 10/387,279 2003 .03 .12 (33) Country US 200511037 (43) Publication Date : 2004 .09.30 (43) Publication Journal Date : 2004 .11.04 (71) Applicant(s) ATI INDUSTRIAL AUTOMATION (72) Inventor(s) Perry, Dwayne; Heavner, Richard-1- A robotic tool changer with an improved safety interlock includes a master unit, a tool unit, and a coupler movable between coupled and decoupled positions and operative to couple the master and tool units. A circuit for actuating the coupler is associated with the tool unit, for connection to an interlock that closes when the tool is safely parked in a tool stand. The circuit enables the coupler to assume the decoupled position when the master and tool units are coupled and the circuit is closed. The robotic tool changer additionally includes a circuit operative to enable the coupler to assume the decoupled position when the master unit is decoupled from the tool unit. CLAIMS What is claimed is : 1. A robot tool changer comprising : a master unit; a tool unit ; a coupler movable between coupled and decoupled positions and operative to couple said master and tool units ; an electrical circuit for actuating said coupler, including : contacts associated with said tool unit and operative to enable said coupler to assume said decoupled position when said contacts are electrically connected ; and a first switch operative to enable said coupler to assume said decoupled position only when said master unit is decoupled from said tool unit.
2. The tool changer of claim 1 wherein said contacts are connected to a second switch associated with a tool connected to said tool unit, wherein said second switch is closed when said tool unit is located in a tool stand.
3. The tool changer of claim 2 further comprising at least one test contact associated with said tool unit.
4.. The tool changer of claim 3 wherein said second switch includes a switch status indicator, and wherein said switch status indicator is connected to said at least one test contact. <Desc/Clms Page number 16> 5. The tool changer of claim 1 wherein said first switch includes a switch status indicator.
6. The tool changer of claim 1 further comprising a controller operative to energize said electrical circuit to actuate said coupler to the decoupled position.
7. The tool changer of claim 6 wherein, when energized by said controller, said electrical circuit actuates said coupler to the decoupled position only when either said first or second switch is closed.
8. The tool changer of claim 7 wherein said controller is a DeviceNet controller.
9. The tool changer of claim 1 further comprising a sensor operative to detect when said master and tool units are coupled.
10. The tool changer of claim 9 wherein said sensor is operative to open said first switch when said master and tool units are coupled. <Desc/Clms Page number 17> 11. A method of safely decoupling a tool unit from a master unit of a robot tool changer, said tool changer including a coupler movable between coupled and decoupled positions and operative to couple said master and tool units, comprising : sensing whether a tool connected to said tool unit is located in a tool stand ; sensing whether said master unit and said tool unit are coupled; and moving said coupler to said decoupling position only when either said master and tool unit are coupled and said tool is located in a tool stand ; or said master and tool unit are decoupled.
12. The method of claim 11 further comprising sensing the status of switches in an electrical circuit operative to move said coupler to said decoupling position.
13. The method of claim 11 wherein sensing whether a tool connected to said tool unit is located in a tool stand comprises sensing the state of electrical contacts associated with said tool unit. <Desc/Clms Page number 18> 14. A robot tool changer comprising: a master unit ; a tool unit ; a coupler movable between coupled and decoupled positions and operative to couple said master and tool units ; a first circuit associated with said tool unit ; a second circuit associated with said master unit; said first and second circuits being connected when said master unit is coupled to said tool unit; wherein said first circuit is operative to enable the coupler when said master unit and tool unit are coupled ; and wherein said second circuit is operative to enable the coupler when said master unit and tool unit are decoupled.
15. The robotic tool changer of claim 14 wherein said first circuit is operative to enable the coupler only when said master unit and tool unit are coupled and said second circuit is operative to enable the coupler only when said master unit and tool unit are decoupled.
16. The robot tool changer of claim 14 wherein said first circuit is an electrical circuit and includes a set of contacts and wherein when said master and tool units are coupled, said coupler is enabled when said set of contacts are electrically connected.
17. The robotic tool coupler of claim 16 wherein said second circuit is an electrical circuit and includes a switch that is actuated in response to said master and tool units being coupled. <Desc/Clms Page number 19> 18. The robot tool changer of claim 17 wherein when said master and tool units are decoupled said switch is positioned to enable the coupler irrespective of whether said set of contacts are connected or not, and wherein the coupling of said master and toot units actuates said switch such that said coupler can only be enabled by said set of contacts being electrically connected.
19. The robot tool changer of claim 14 wherein said first and second circuits are pneumatic circuits and wherein when said master and tool units are coupled, said coupler is enabled when said first circuit is plugged.
20. The robot tool changer of claim 14 wherein said first and second circuits are physically separated when said master and tool modules are decoupled, and wherein said first and second circuits are connected when said master and tool units are coupled.
21. The robot tool changer of claim 16 wherein said set of contacts is carried by the tool unit.
22. The robot tool changer of claim 17 wherein said coupler normally assumes a coupled position and wherein said robotic tool changer includes a controller operatively connected to said switch for directing an uncoupling signal to said switch. <Desc/Clms Page number 20> 23. A robot tool changer comprising: a master unit; a tool unit ; a coupler movable between coupled and decoupled positions and operative to couple said master and tool units ; a control circuit for selectively controlling the transmission of a control signal to the coupler, the control circuit including: a first circuit associated with the tool unit and including a set of contacts ; a second circuit including a switch operative to receive the control signal and movable between first and second positions; the first and second circuits being electrically connected as a result of the master and tool units being coupled ; said switch assuming a first position when the master and tool units are decoupled such that the control signal is directed to the coupler ;STDC0260 said switch assuming the second position in response to the master and tool units being coupled ; and wherein when said switch assumes the second position the control signal is directed to the coupler only if the set of contacts are electrically connected.
24. The robot tool changer of claim 23 including a controller for directing the control signal to the switch.
25. The robot tool changer of claim 24 wherein the controller includes an input, and wherein when said switch is in the second position, the control signal is directed to said input. <Desc/Clms Page number 21> 26. The robot tool changer of claim 23 wherein the set of contacts are connected to a switch associated with a tool.
27. The robot tool changer of claim 23 including a sensor for sensing the coupling of the master and tool units and for causing the switch to assume the second position. <Desc/Clms Page number 22> 28. A method of controlling the decoupling of a robot tool changer having a master unit, tool unit, coupler and a set of contacts carried by the tool unit, comprising : sensing when the tool unit is decoupied from the master unit and permitting the coupler to be actuated such that the coupler may be moved from a coupled position to a decoupled position ; and sensing when the tool unit is coupled to the master unit, and permitting the coupler to move from the coupled position to the decoupled position only when the set of contacts carried by the tool unit are electrically connected.
29. The method of claim 28 wherein the coupler normally assumes a coupled position and wherein the method includes enabling a control signal to be directed to the coupler when the tool unit is decoupled from the master unit; and when the tool unit is coupled to the master unit, enabling the control signal to be directed to the coupler only when the set of contacts carried by the tool unit are electrically connected.