RELEASABLE COUPLING MEANS FOR ROBOTS

Abstract: A coupling arrangement which facilitates the releasable coupling of a selected tool to a robot machine (3), said coupling arrangement which comprises first and second coupling parts (1, 2) attached or adapted to be attached, respectively, to the robot machine and a tool (4) required to be releasably coupled to the machine, the coupling parts having mutually engageable operating/control/monitoring connections (e.g. electrical, optical, hydraulic or pneumatic connections) for permitting various tool operating control and/or other functions to be performed via the coupling arrangement when the two coupled parts are in mutual engagement and in which one of the coupling parts is provided with power-operated locking means (9, 10) for releasably locking the two coupling parts in their condition of mutual engagement.

Description: Releasable coupling means for robots. This invention relates to robot machines and relates more specifically to arrangements for releasably coupling different tools to robot machines according to specific work requirements. According to the present invention there is provided a coupling arrangement which facilitates the releasable coupling of a selected tool to a robot machine said coupling arrangement comprising first and second coupling parts attached or adapted to be attached respectively to the robot machine and a tool required to be releasably coupled to the machine, the coupling parts having mutually engagable operating/control/monitoring connections (e.g. electrical, optical hydraulic or pneumatic (i.e. air pressure or vacuum^ connections) for permitting various tool control and/or other functions to be performed via the coupling arrangement when the two coupled parts are in mutual engagement and in which one of the coupling parts is provided with power-operated locking means for releasably locking the two coupling parts in their condition of mutual engagement. As will be appreciated, the robot machine may be controlled to select any one of a number of different tools in accordance with the work program the robot machine is to perform and accordingly each of the tools concerned may have attached to it a second coupler part in readiness for coupling to the first coupling part attached to the robot machine. According to an alternative arrangement a tool having attached to it the second part of a coupling arrangement could be selected by different robot machines each having attached to them the first part of a coupling arrangement according to the invention. The hydraulic and/or pneumatic connections may be made by means of a rigid connector pipe or pipes and it may conveniently be arranged that the connector pipe or pipes serve as coupling pin means which co-operate with the power operating locking means referred to in order to effect locking between the two parts of the coupling arrangement. For example, the coupling pin means may be provided with notches or grooves which are lockingly engaged by the rams of locking ram means to releasably secure the two parts of the coupler in mutual engagement. By way of example one embodiment of the present invention will now be described with reference to the accompanying drawings in which: Figure 1 is a side elevational view of a releasable tool coupling arrangement according to the invention; Figure 2 is an end view of the coupling arrangement of Figure 1 taken in the direction X of Figure 1 but rotated through 90 ° ; Figures 3 and 4 are cross-sectional views of the coupling arrangement of Figure 1 taken along the section lines A-A and B-B, respectively, in Figure 2; and, Figures 5 and 6 are views along the lines C-C and D-D, respectively, in Figure 4. Referring to the drawings, the coupling arrangement illustrated comprises two coupling parts 1 and 2 which are shown coupled together and which are adapted to be connected, respectively, to the arm of a robot machine shown in part at 3 and a power tool or tool holder shown in part at 4 in Figure 1. The coupling part 1 has a hollow neck or stem 5 which serves to accommodate a cable form (not shown) extending from the robot machine 3 to a socket part 6 having terminals 6a of a multi-contact electrical connector secured to a recessed head part 7 of the coupling part 1 by screws 8, as can best be seen in Figure 4. Figure 5 shows the recessed form of the head part 7 for accommodating the connector socket part 6. The head part 7 of the coupling part 1 is also fabricated to accommodate two hydraulically operated locking mechanisms 9 and 10 both of which are shown in Figures 2 and 5 and each of which comprises a ram 11 the nose portion 12 (Figure 3) of which can be displaced into or out of a passageway 13 (Figure 3 ) which receives one of two tubular coupling pins 14 and 15 secured to a body part 16 of the coupling part 2. Hydraulic fluid hoses (not shown) for facilitating the transmission of actuating pressures to the rams 11 of the locking mechanisms will extend from the robot machine 3 to the ends of the two locking rams. Figure 1 shows the coupling part 2 attached to the power operated tool 4. This power operated tool or tool holder 4 may, for example, comprise one of a number of different tools which are required to be selectively coupled to the robot machine 3 according to the particular task to be performed by the machine under the control of a programmed computer (not shown). The power operated tool may, for example, comprise an electrically operated servo-controlled gripper device or a pneumatic gripper controlled by air pressure or vacuum, but it will be appreciated that any other suitable tools (e.g. hydraulically or even optically-operated) may alternatively be selectively employed. Accordingly, the tool selected may need to derive electrical, pneumatic, hydraulic or optical operating control signals over the coupling between the coupling parts 1 and 2. To facilitate the releaseable coupling between the coupling parts 1 and 2 and at the same time provide a pneumatic and/or hydraulic connection between the selected tool 4 and the robot machine 3, the body part 16 of the coupling part 2 has secured to it the pair of tubular coupling pins 14 and 15. These coupling pins engage respective axially-extending holes 13 and 17 in the head part 7 of the coupling part 1. The tubular coupling pins are provided with suitably located notches, such as the notch 18 (Figure 3), which is adapted to be engaged by the nose 12 of the appertaining locking ram 11 in order to lock the coupling parts 1 and 2 in mutual engagement. As can best be seen in Figure 3, the free ends of the tubular coupling pins 14 and 15 which are preferably substantially flat, as shown, but which may be chamfered, are arranged to make fluid-tight engagement with respective bush seals, such as the bush seal 19 (Figure 3). Input ports, one of which is shown at 20 in Figure 3, will have pneumatic or hydraulic hoses or pipes (not shown) connected thereto from the robot machine. The mutually engaged coupling parts 1 and 2 of the coupling arrangement thus effectively provide a pneumatic connection between the robot machine 3 and the selected tool 4. As can be seen from Figure 4, the coupling part 2 also has attached to it a plug part 21 of the electrical connector previously referred to, the pin contacts of this plug part mating with those of the socket part 6 as the two coupling parts 1 and 2 of the arrangement are brought together. Thus electrical connections will be effected between the robot machine 3 and a cable form (not shown) extending from the electrical connector to the tool or tool holder 4 to enable electrical signals to be transmitted through the coupling arrangement to the tool for the control thereof in accordance with a particular work program. It may here be mentioned that one or more of the electrical connections established through the coupled parts 1 and 2 by the multi-contact electrical connector having parts 6 and 21 and associated cable forms (not shown) may be replaced by an optical fibre coupling arrangement which provides optical connection(s) between optical fibres in response to the mutual coupling of the two parts 1, 2 in mutual engagement. Optical fibre cabling will accordingly extend from the robot machine 3 to the tool 4 and such an optical arrangment may provide for the transmission of visible or invisible (e.g. infra-red) optical signals between the machine and the tool as for the purpose of on-line robotic inspection from simple "part-present" detection to complex camera/vision systems. Three dimensional/stereo sensor systems can be achieved by the use of only one optical fibre using storage and fixed tool offset techniques. The coupling part 2 may include dowel means 22 and keyways 23 for locating the tool or tool holder 4 relative to the coupling part 2. As will be appreciated from the foregoing description of one specific embodiment of the present invention the invention enables electrical and/or optical and pneumatic and/or hyraulic connections to be made between robots and selected tools connected thereto in order to provide the requisite tool operating services. The selection of the tools and the changing of tools can be performed quickly and accurately by the robot machine 3 without the need for human intervention. Clearly, many other embodiments of the invention may be employed without departing from the overall spirit of the invention.

Claims: CLAIMS : 1. A coupling arrangement which facilitates the releasable coupling of a selected tool to a robot machine, said coupling arrangement comprising first and second coupling parts attached or adapted to be attached, respectively, to the robot machine and a tool required to be releasably coupled to the machine, the coupling parts having mutually engageable operating/control/monitoring connections (e.g. electrical, optical, hydraulic or pneumatic connections) for permitting various tool operating control and/or other functions to be performed via the coupling arrangement when the two coupled parts are in mutual engagement and in which one of the coupling parts is provided with power-operated locking means for releasably locking the two coupling parts in their condition of mutual engagement. 2. A coupling arrangement as claimed in claim 1, in which the two coupling parts are arranged to be locked together by means of hydraulically-operated ram means. 3. A coupling arrangement as claimed in claim 1 or claim 2, in which one of the coupling parts has tubular coupling pin means extending therefrom for engaging one or more holes in the other coupling part to provide a sealed passageway through the coupling arrangement for hydraulic fluid, air, etc. from the robot machine for the remote operation or control of the tool. 4. A coupling arrangement as claimed in claims 2 and 3, in which the hydraulically-operated ram means engages with notch means in the coupling pin means to lock the coupling parts in mutual engagement. 5. A coupling arrangement as claimed in claim 1, in which the two coupling parts are provided with the respective parts of a multi-contact electrical connector which provides through electrical connections between cabling extending from the robot to the tool when the two coupling parts are mutually coupled. 6. A coupling arrangement as claimed in claim 1, or claim 5 in which the two coupling parts are provided with respective parts of an optical fibre connector for connecting optical fibres extending between the robot machine and the selected tool when the coupling parts are in mutual engagement. 7. A coupling arrangement as claimed in claim 6, in which optical fibre connector forms a part of the multi-contact electrical connector. 8. A coupling arrangement as claimed in any preceding claim, in which the respective coupling parts have passageways extending axially therethrough for the passage of electrical and/or optical cabling etc. 9. A coupling arrangement as claimed in any preceding claim, in which the coupling part adapted to be attached to the tool has one or more key ways and/or dowel means for correct orientation of a tool holder relative to the coupling part.

Inventors: WALLACE CHRISTOPHER, WALLACE, CHRISTOPHER
Applicants: PLESSEY OVERSEAS, PLESSEY OVERSEAS LIMITED
Application year: 1985
Main classification: B25J15
IPC codes: B25J15, B25J19