METHOD AND APPARATUS FOR ACCURATE POSITIONING OF A SOLID COMPONENT FOR A ROBOTIC PICKUP

Abstract: Electrical connectors (12) having terminal pins (20) are transported along a guide track (24) with linear arrays of the pins (20) depending from each connector (12) received in slots (26, 28) formed in the track. Conveyance of each connector (12) is completed when a leading projection (20a) contacts an accurately positioned stop wall (48). An alignment bar (50) presses the pins (20) against a track wall (58) of the slot (26). The pins (20) are thus accurately positioned relative to the robotic pickup arm (52) for transfer of the connector to a mounting station (22) with the pins aligned with receiving holes (23a) in a printed circuit board (23).

Description: This invention relates to an apparatus and method for aligning a solid component having rigid projections in preparation for pickup of the solid component by a robotic mechanism, see e.g. EP-A-0 120 159. The accuracy of an automated robotic placement of a solid component at a required location is directly related to the accuracy of positioning the robotic head during pickup of the solid component and convenient, accurate alignment techniques, compatible with an automated pickup process, are necessary. One example of a solid component being robotically placed, is an electrical connector of the type having a dielectric body, with one or more arrays of outwardly extending metallic terminal pins mounted therein. For a totally automated placement of such connectors, an accumulation of placement inaccuracies must be considered, and the sum total of all such inaccuracies must be carefully controlled. For example, the terminals of such connectors are typically inserted in mounting holes drilled in a printed circuit board. In a fully automated process, a robotic pickup and insertion head would acquire a connector from a remote source such as a tray or the like, would move to a position on the printed circuit board, and would lower the connector a predetermined amount, thereby inserting the connector terminals in the mounting holes of the printed circuit board. However, with the increasing number of leads required in connectors, the closer spacing between leads and the closer spacing of components on the printed circuit board, it is becoming increasingly difficult to position each terminal of an array of a large number of closely spaced terminals in the array of mounting holes in the printed circuit board. In addition to inaccuracies of positioning successive printed circuit boards relative to a robotic insertion head, the inaccuracies of robotic movement from origin to destination, and the inaccuracies of the location of mounting holes relative to printed circuit board positioning holes, there is an inaccuracy in the position of connector terminals relative to the housing edge surfaces which are typically engaged by a robotic gripper head. The aggregate effect of these inaccuracies renders it difficult to insert all the leads of a connector into all of the printed circuit board mounted holes simultaneously, without causing damage to the leads or to the mounting holes. When loading connector terminals in a connector housing, it is possible to maintain their precise location with respect to each other with a fairly high degree of accuracy. Unfortunately, however, the position of the connector terminals with respect to external edge surfaces of the connector housing may vary significantly from connector to connector. In the past, attempts to automatically align the pins of the connector to the printed circuit board have used the external edges connector housing as the reference for alignment. Since the terminals have a potential error in placement with respect to the connector housing, they also have a potential error in placement with respect to the mounting holes. Hence, the common technique used in the prior art to align the terminals to the mounting holes is to place the connector on the printed circuit board so that terminals of the connector are approximately aligned with the mounting holes. Final alignment is accomplished by an additional automated process, or manually, by an operator. One example of an alignment apparatus and method for use with an automated assembly process, is described in U.S. Patent No. 4,479,298. The patent addresses the need of accurately positioning the various wafer-like stages of an integrated circuit (IC) package assembly. The technique used requires an alignment fixture, comprising a coarse alignment pedestal mounted on a fine alignment block, for receiving the IC package and aligning the leads thereof with respect to a two dimensional reference co-ordinate system. The leads of the package, however, are of a surface mount type, having solder pads extending parallel to the wafer-like body. The arrangment disclosed is for fixing the location of the leads, relative to the remainder of the IC package, and does not address the need for accurately positioning a component in three dimensional space in preparation for pickup by a robot arm or the like automated assembly technique. United Kingdom Patent Application 2,131,331 describes a technique to aid in the robotic placement of a plurality of different shaped components on a printed wiring board. The technique uses a template designed for use with a particular printed wiring board, having accurately dimensioned openings for receiving the plurality of electronic components. To aid in seating the components in the template and to aid introducing the leads thereof into the mounting holes of the printed wiring board, the template and board are vibrated. This technique is not concerned with the accurate pickup of a component with a robotic arm, since it compensates for any inaccuracies by using the template to guide the components after they are robotically placed at their final destination. U.S. Patent No. 4,459,743 describes a technique for the atuomatic mounting of chip components, stored in a parts hopper, for placement on a printed circuit board. The system uses a combination of X direction and Y direction shuttle mechanisms. The components are conveyed downwardly along a sliding track, with the outermost projecting surface thereof coming to rest against a stopper member. Thereafter, the part is conveyed to the X-Y conveyance apparatus. U.S. Patent No. 4,470,182 Zemek et al, discloses an arrangement for centering electrical components that are mounted on a paper tape substrate. The arrangement displaces the components along their longitudinal centerlines, in a direction perpendicular to the axis of the paper tape substrate. The arrangement uses a pair of spaced apart arms which come together, to provide an automatic centering of the components, relative to the centerline of the arm mechanism. It is therefore apparent that a need exists in the art for an apparatus and method to accurately align the terminals of an electrical connector to the mounting holes of a printed circuit board to which the connector is to be mounted. Such an apparatus and method, if compatible with automated robotic insertion techniques would not only lower the manufacturing costs but also would improve the quality of the electronic device produced. EP-A-0120159 discloses a method of and apparatus for handling a component, having a body and one or more members protruding therefrom such that the protruding members are put in proper mating registration with corresponding holes in a substrate or the like, a gauge being used to effect the alignment. However, the component handling means involves moving the component to three stations prior to insertion at a fourth station and this process is time consuming. It is therefore an object of the present invention to provide a method of and an apparatus for accurately positioning a solid body from a loading station to a remote mounting station on a mounting surface by means of a robotic arm. Thus, from one aspect, the present invention provides a method of accurately positioning a solid body from a loading station to a remote mounting station on a mounting surface by means of a robotic arm in which the body has an external surface defined between a pair of opposed external edges, and at least one linear array of projections having a predetermined configuration depending from said external surface located between said external edges. The mounting surface includes a linear array of projection-receiving apertures having a configuration corresponding to that of said linear array of said projections. The robotic arm has a head which engages said external edges of said solid body, to pick up and thereby withdraw said solid body from said loading station, moving said solid body to said remote mounting station so as to overlie said array of projection-receiving apertures, and lowering said solid body so as to insert said solid projections in said apertures. The linear array of projections is positioned along a reference line a-b having a configuration corresponding to that of said linear array of projections, where a is a position of a lead projection; the robotic head is positioned to overlie said connector at a given orientation with respect to said reference line; said edges of said solid body are gripped independent of the orientation of said head; said arm is raised withdrawing said solid body from said loading station, and then moved so moving said solid body to said mounting station; said head is orientated such that said projections overlie and are aligned with said linear array of mounting holes; and said head is lowered so inserting said solid projections in said apertures. The present invention also provides apparatus for accurately positioning a solid body from a loading station to a remote mounting station on a mounting surface by means of a robotic arm, the body having an external surface defined between a pair of opposed external edges, and at least one linear array of projections having a predetermined configuration depending from said external surface located between said external edges. The mounting surface includes a linear array of projection-receiving apertures having a configuration corresponding to that of said linear array of said projections. The robotic arm has a head which engages said external edges of said solid body, means to pick up and thereby withdraw said solid body from said loading station, means for moving said solid body to said remote mounting station so as to overlie said array of projection-receiving apertures, and means for lowering said solid body so as to insert said solid projections in said apertures. Means is provided for positioning said linear array of projections along a reference line a-b having a configuration corresponding to that of said linear array of projections, where a is a position of a lead projection; together with means for positioning the head to overlie said connector at a given orientation with respect to said reference line; means for gripping said edges of said solid body independent of the orientation of said head; means for raising said arm and withdrawing said solid body from said loading station, and for moving said solid body to said mounting station; means for orientating said head such that said projections overlie and are aligned with said linear array of mounting holes; and means for lowering said head and inserting said solid projections in said apertures. Some ways of carrying out the present invention in both its method and apparatus aspects will now be described by way of example, and not by way of limitation, with reference to drawings which show specific embodiments of apparatus in accordance with the present invention. In the drawings, wherein like elements are referenced alike, FIG. 1 is a plan view of a robotic insertion mechanism according to the present invention which accurately positions electrical components between component pickup and placement stations; FIG. 2 is a cross-section on line 2-2 in Fig. 3. FIG. 3 is an elevation of part of the mechanism shown in Fig. 1 in the direction of arrows 3 in Fig. 2; FIG. 4 is a plan view of a further mechanism according to the present invention as seen in the direction of arrows 4-4 in Fig. 5; FIG. 5 is a cross-section on line 5-5 in Fig. 4; FIG. 6 is a cross-section on line 6-6 in Fig. 7 of part of a still further mechanism in accordance with the present invention prior to positioning of an electrical connector; FIG. 7 is a plan view of the arrangement of Fig. 6; ready for withdrawal by a robotic insertion head; FIG. 8 is a cross-section corresponding to Fig. 6 showing the electrical connector in its final position at the loading station; and FIG. 9 is a plan view of the arrangement of Fig. 8. Referring now to the drawings, Fig. 1 is a plan view of a component loading station 21, a component mounting station 22, and a robotic insertion mechanism 52 which transports solid components between the two stations. The solid components being moved between the stations are of a type having solid projections extending from an external surface thereof. An example of this type of component is illustrated in the figures as an electrical connector 12. Connector 12 (see Figs. 1 and 3) has a solid dielectric body 14, with an upper surface 16, and a lower support surface 18, and two linear arrays of metallic terminals or solid projections 20 depending from surface 18. As is known in the art, connector 12 is conveyed along a feed track 24 comprising two spaced apart projection-receiving slots 26, 28 formed between outside track walls 30, 32 and a medial track wall 34. Track walls 30, 32, 34 each have an upper surface designated by the subscript u, for contacting and slidingly supporting the support surface 18 of connector bodies 14. Referring again to Fig. 1, it can be seen that the linear arrays of projections 20 of each connector 12 are maintained in fairly close alignment with projection receiving slot 26. However, the dielectric bodies 14 of each connector are not maintained in such alignment, as is shown in Fig. 1, to a greatly exagerrated extent for the purposes of illustration. Accurate positioning of the terminals 20 with respect to the terminal receiving apertures 23 a in a printed circuit board or the like mounting surface 23 is accomplished in a single "pick and place" operation. Referring to Figs. 2 and 3, locating apparatus gnerally designated at 10, comprises an extended section of track 24 having a free end 44. The upper support surfaces of apparatus 10 are accurately positioned to provide the correct placement height for connector 12. A stop wall 48 is provided in slot 26 adjacent the free end 44 of apparatus 40, being positioned to contact only a leading projection (designated 20 a in Fig. 2), avoiding contact with connector body 14. Stop wall 48 provides a first accurate positioning of leading projection 20 a , in the plane of Fig. 2, which is independent of the relative position between projection 20 a and connector body 14. Also located in slot 26, is a moveable alignment bar 50, generally coextensive with the linear array of projections 20. Initially, bar 50 is positioned immediately adjacent medial track wall 34 to provide clearance for the projections 20, ensuring engagement between leading projection 20 a and stop wall 48. The initial position of bar 50 is provided by a plurality of release springs 53 which urge bar 50 against medial track wall 34. Upon engagement of the leading projection 20 a with stop wall 48, solenoid 54 is energized to move alignment bar 50 toward outside track wall 30, which includes a reference surface 58 communicating with slot 26. Movement of alignment bar 50 causes the linear array of projections 20 to be pressed against surface 58, thereby providing a second accurate positioning of leading projection 20 a in the plane of Fig. 2, owing to the accurate positioning of reference surface 58, formed parallel to the longitudinal axis of track 24. When fully seated in slot 26, at its forwardmost position, the leading projection 20 a of connector 12 is confined by three surfaces: track wall reference surface 58, stop wall 48, and alignment bar 50, to accurately position the leading projection 20 a in the plane of Fig. 2. With the upper surfaces of the track walls also being accurately positioned, projection 20 a is accurately fixed in three dimensional space. To review the alignment afforded by the present apparatus, connectors 12 have a linear array of projections 20 depending therefrom. These projections are to be received in the mounting apertures 23 a formed in the mounting surface of a printed circuit board 23. The linear array of apertures 23 a has the same configuration as the linear array of terminals 20, the problem being to provide an accurate pickup and placement of the array of terminals with respect to the array of apertures 23 a . Connectors 12 are advanced along a track 24 until they reach a loading station 21, whereupon the linear array of projections 20 is positioned along a reference line a-b located in track 26, where a corresponds to the position of the leading projection 20 a . With the array of terminals 20 being fixed in space, a robotic arm-like pickup mechanism 52 is brought into alignment with line a-b. Robotic mechanism 52 includes a lower floating gripper head 52 a which is mounted for independent "floating" movement with respect to an upper placement arm 52 b . Gripper head 52 a includes gripper-like fingers 52 c which engage edge surfaces of connector body 14. Placement arm 52 b has defined therein a reference line a'-b' having the same configuration as reference line a-b. As can be seen in Fig. 1, placement arm 52 b is mounted for pivotable movement at 52 e and is capable of telescopic extension, provided by a telescoping mechanism 52 d . Robotic mechanism 52 is of a type well known in the art, capable of precisely repeating a programmed path of movement. The path of robotic movement is programmed to position pivot mounting 52 e at point 52 f , and to align reference line a'-b' of placement arm 52 b with line a-b of loading station 21. The floating gripper head 52 a is programmed for independent movement (with respect to arm 52 b ) to straddle the gripper arms 52 c across opposed edges of connector body 14. Robot arm 52 b is programmed for upward movement to withdraw connector 12 from loading station 21. Thereafter, mechanism 52 is programmed to move connector 12 to mounting station 22, located on the surface of printed circuit board 23. Connector 12 is positioned to overlie apertures 23 a with robotic reference line a'-b' being aligned congruent to the mounting reference line a''-b'', which in turn is congruent with the linear array of projection receiving apertures 23 a . When employed with the positioning arrangement, the robotic pickup arm 52 b maintains its precise alignment with leading projection 20 a , while the floating gripper head 52 a is automatically and independently moved small amounts to facilitate engagement between its arms 52 c and the opposed external surfaces 14 a , 14 b of connector body 14, wherever those surfaces might lie. Thus, the floating gripper head 52 a compensates for any inaccuracies in the relative positioning between projections 20 and the outside surfaces 14 a , 14 b of connector body 14. After the arms 52 c of gripper head 52 a have engaged connector body 14 (with accurate positioning of leading projection 20 a being assured), solenoid 54 is de-energized and bar 50 returns to its original position adjacent medial wall 34, under the bias force of release springs 53. The robotic pickup mechanism 52 is thereafter withdrawn away from the plane of Fig. 2, so as to remove connector 12 from positioning apparatus 10. The next connector 12 in a serial array of connectors is then loaded in apparatus 10 for accurate presentation to the robotic pickup mechanism. If desired, projection receiving and straightening recesses 60 may be formed in reference surface 58 to aid in aligning and straightening the projections with respect to each other and with respect to the reference surface 58. Only a few of the recesses 60 are shown on Fig. 2, for the purpose of clarity. However, in the preferred embodiment, all of the projections have corresponding recesses 60. In the present apparatus, accurate positioning of projections 20 relative to a robotic pickup mechanism is accomplished, as opposed to prior art techniques of aligning the external connector body surfaces to the pickup mechanism. The apparatus of Figs. 4 and 5 also provides accurate positioning of an electrical connector or the like solid component 12 in three dimensional space. Connector 12 is conveyed along feed track 24 for presentation to a positioning station designated at 160. Track 24 is substantially identical to that described above with reference to Figs. 2 and 3, except medial wall 34 is terminated at a free end 34 a located upstream of station 160. Station 160 is defined in part by a retractable positioning finger 162 which projects into track 26 to engage the leading projection 20 a of connector 12. At station 160, connector 12 is held in a vertical position by track walls 30, 32, which are dimensioned to provide clearance for reception of a gauge block 166 therebetween. Gauge block 166 is of a type having an upper wall 172 defining a plurality of accurately dimensioned, close tolerance projection-receiving apertures 168 communicating with funnel-shaped entrance portions 170. Apertures 168 are arranged in two linear arrays, corresponding to the desired configuration of the serial arrays of projections 20, in connector 12. As is known in the art, gauge block 166 when applied to projections 20, straightens any bends or other malformations in projections 20, providing the desired configuration for the projections, as well as the desired spacing between projections. Gauge block 166 is provided with a mounting, not shown in the figures, for accurate positioning in three dimensional space. Thus, in addition to providing the usual correction to projections 20, gauge block 166 is employed in the present apparatus to provide an extremely accurate positioning of those projections, for presentation to a robotic pickup mechanism or the like automated positioning apparatus. As gauge block 166 is upwardly advanced, projections 20 are received within apertures 168 to fix those projections accurately in the plane of Fig. 4. An upper stop wall 176 is positioned to overlie the upper surface 16 of connector 12, to balance the upward force generated by the frictional engagement between projections 20 and apertures 168 of gauge block 166. After projections 20 are fully received in apertures 168, gauge block 166 (with the connector 12 engaged therewith), is advanced in a rightward direction to assume the final loading station 178 shown in the righthand portions of Figs. 4 and 5. Loading station 178, which corresponds to station 21 of Fig. 1, is defined by a block 180 which engages the leading end 166 a of gauge block 166 to define a final, accurately determined position in the plane of Fig. 4. Driving mechanisms for raising gauge block 166 can, as is known in the art, be provided with an accurately defined upper limit so as to accurately position the upper surface 172 of gauge block 166. Thus, connector 12, in its final loading station 178, is accurately positioned in three dimensional space, and is made accessible to the robotic pickup mechanism 52 (not shown) located above track 24. With the projections 20 of connector 12 being accurately placed, the pickup position of the robotic mechanism can be accurately and precisely aligned with the final loading station. With projections 20 being accurately fixed at loading station 178, and thereby being aligned with a robotic pickup mechanism, the floating gripper head 52 a can be lowered to engage the outer surfaces 14 a , 14 b of connector body 14. The driving mechanism for raising gauge block 166 holds the gauge block fixed while connector 12 is lifted out of the gauge block by the robotic pickup mechanism 52. Thereafter, gauge block 166 can be returned to its initial positioning station 160 for presentation of another connector 12 in a serial array of connectors carried along track 24. With the present apparatus, any variation in the relative location of projections 20 with respect to external surfaces 14 a , 14 b can be automatically compensated by the various floating gripper head arrangements in use today. It has been assumed in the discussion above, that the solid projections 20 are rigidly fixed in connector body 14. However, other types of connectors have terminals loosely positioned in the connector body. The degree of freedom of these terminals is significantly greater than the tolerance required for robotic placement on a printed circuit board. Apparatus as described herein with reference to the drawings when employed with a robotic gripper mechanism having arms which also engage projections 20 adjacent the support surface 18 of connector body 14, can provide a close tolerance simultaneous placement of all projections 20 of a given linear array, in a linear array of printed circuit board mounting holes. In Figs. 6 to 9, the locating apparatus designated generally at 210 has track 24 substantially identical to the guide tracks described above, except that a necked-down portion 234 is aligned with intermediate wall 34 to provide a smooth transition with a guide bar 260 of reduced width. As connector 12 slides along track 24, it is supported in its upstream position by track walls 30, 32, 34. Upon reaching the final loading station of Figs. 6 to 9, it is supported from below by guide bar 260 and by longitudinally extending moveable bars or follower plates 300 which prevent connector 12 from tipping sideways, becoming dislodged from guide bar 260. A groove 18 a formed in support surface 18 of connector body 14 receives the upper portion of guide bar 260 to aid in maintaining the desired orientation of connector 12 in apparatus 210. A shuttle assembly, designated generally at 310, provides the final delivery of connector 12 to the loading position shown in Fig. 8, for presentation to a floating gripper head 52 a of a robotic pickup mechanism 52. Shuttle 310 includes a gauge block 166' substantially identical to gauge block 166 previously described, but for a vertically extending slot 316 which receives guide bar 260. Gauge block 166' is accurately positioned by a stop wall 320 which abuts one end 266 a of gauge block 166', in sliding engagement therewith. As gauge block 166' is raised, it engages connector projections 20 in accurately dimensioned apertures 168 having funnel shaped openings 170. During elevation of gauge block 166', connector 12 is restrained against upward movement by retaining fingers 330 formed at the upper end of latch arms 332. Latch arms 332 include a vertically extending beam member 336 having a pivotal mounting projection 338 and an outwardly extending cam arm 342 formed at its lower end. Beam members 336 and outwardly extending cam arms 332 together present a continous camming surface 344 to stationary cam blocks 348 having a fulcrum point 350. Projections 338 are received in apertures 354 formed in follower plates 300 to provide a pivotal mounting for latch arms 332. As gauge block 166' is raised, its upper surface 167 contacts the bottom mounting surface 18 of connector 12, as well as the bottom free end of follower plates 300. Further upward movement of gauge block 166' causes connector 12, follower plates 300, and latch arms 332 to be elevated as a single unit, once projections 20 are fully received in gauge block apertures 168. As can be seen in Fig. 6, cam blocks 348 are formed as an extension of a mounting base 360. Latch arms 332 further include tab-like extensions 364 which are biased in a downward direction, owing to their engagement with spring loaded pin 370 which projects beyond the lower portion of mounting base 360. A spring 372 biases pin member 370, providing the downward spring force imparted to latch arms 332, which maintains engagement between retaining fingers 330 and the top surface 16 of connector body 14. As gauge block 166' is elevated, latch arms 332 undergo two distinct motions, owing to the configuration of their camming surface 344. Initially, fulcrum points 350 of stationary cam blocks 348 engage the upper portions 344 a of cam surface 344, ensuring engagement between retaining fingers 330 and the upper surface 16 of connector body 14. As the transition point 344 b of cam surface 344 is elevated to contact fulcrum 350, latch arms 332 begin an outward pivotable deflection, eventually achieving the position shown in Fig. 8. As indicated in Fig. 8, clearance is provided to allow the fingers 52 c of robotic floating gripper head 52 a to engage the upper end of connector 12 for subsequent withdrawal of the connector from the shuttle assembly mechanism 310. Thereafter, gauge block 166' is lowered to its initial position, latch arms 332 are drawn together, and another connector 12 is inserted into apparatus 210. Fingers 330 prevent bowing of connector 12 as it rebounds against stop wall 320. As before, the driving mechanism which lifts the shuttle assembly holds the gauge block fixed during withdrawal of connector 12 therefrom.

Claims: A method of accurately positioning a solid body from a loading station to a remote mounting station on a mounting surface by means of a robotic arm, said body having an external surface defined between a pair of opposed external edges, and at least one linear array of projections having a predetermined configuration depending from said external surface located between said external edges, said mounting surface including a linear array of projection-receiving apertures having a configuration corresponding to that of said linear array of said projections, said robotic arm having a head which engages said external edges of said solid body, to pick up and thereby withdraw said solid body from said loading station, moving said solid body to said remote mounting station so as to overlie said array of projection-receiving apertures, and lowering said solid body so as to insert said solid projections in said apertures, characterized by: positioning at the loading station, said linear array of projections along a reference line (a-b) having a configuration corresponding to that of said linear array of projections, where (a) is a position of a projection; positioning the head of the robotic arm to overlie said positioned solid body at that given orientation with respect to said reference line; gripping said edges of said solid body independent of the orientation of said head; raising said arm and withdrawing said solid body from said loading station, and moving said solid body to said mounting station; orientating said head such that said projections overlie and are aligned with said linear array of mounting holes; and lowering said head and inserting said solid projections in said apertures. The method of claim 1 wherein the step of positioning said linear array of projections along a line (a-b), where (a) is the position of a projection, comprises the steps of: positioning said projection against a stop wall defining said position (a); and positioning said linear array of projections laterally against a straight reference surface defining said line (a-b). The method of claim 1 wherein said step of positioning said linear array of projections along a line (a-b), where (a) is the position of a projection comprises: positioning a gauge block beneath said body, said gauge block having an upper surface defining a linear array of projection-receiving gauging apertures having a configuration corresponding to said linear array of mounting apertures; moving said gauge block toward said solid body so as to engage and receive said solid projections therein; and positioning said gauge block so that said linear array of gauging apertures are congruent to said line (a-b). The method of claim 3 wherein said step of withdrawing said connector from said loading station comprises the step of fixing said gauge block in a predetermined position, and moving said body so as to withdraw said projections therefrom. The method of claim 1 wherein said straight reference surface includes an accurately dimensioned linear array of projection receiving and straightening recesses formed in said reference surface, and said positioning step including the step of aligning said projections with respect to each other and with respect to said reference surface. The method of claim 3 further comprising the step of, subsequent to said engagement of said projections with said gauge block, advancing said gauge block to said loading station. The method of claim 3 further including the step of restraining the upper surface of said solid body against movement away from said gauge block as said gauge block engages said solid projections. The method of claim 7 further comprising the step of advancing said gauge block with said solid projections engaged therein, from a first position upwardly to a second release position adjacent said loading station, where said solid body is freed for upward withdrawal. An apparatus for accurately positioning a solid body from a loading station to a remote mounting station on a mounting surface by means of a robotic arm, said body having an external surface defined between a pair of opposed external edges, and at least one linear array of projections having a predetermined configuration, and depending from said external surface located between said external edges, said mounting surface including a linear array of projection-receiving mounting apertures having a configuration corresponding to that of said linear array of said projections, said robotic arm having a head which is moveable to overlie said solid body and which engages said external edges of said solid body, means to pick up said head and thereby withdraw said solid body from said loading station, means for moving said head to said remote mounting station so as to overlie said array of mounting apertures, and means for lowering said head to thereby lower said solid body so as to insert said solid projections in said mounting apertures, characterized by: means at the loading station for positioning said linear array of projections along a reference line (a-b) having a configuration corresponding to that of said linear array of projections whereby (a) is a position of a projection; means for positioning the head to overlie said body at a first orientation with respect to said reference line and a second orientation with respect to said solid body; means carried by said head for gripping said edges of said solid body while maintaining the orientation of said head to said body; and in that said robotic head is moveable to said mounting station to take the same first orientation with respect to said linear array of mounting apertures, whereby when said head is lowered said projections are accurately inserted in said mounting apertures. The apparatus of claim 9 wherein said means for positioning said linear array of projections along a line (a-b), comprises: a stop wall defining said position (a); an adjacent sidewall having a straight reference surface defining said line (a-b); and means for pressing said linear array of projections laterally against said sidewall. The apparatus of claim 10 wherein said straight reference surface includes an accurately dimensioned linear array of projection receiving and straightening recesses formed in said reference surface. The apparatus of claim 9 wherein said means for positioning said linear array of projections along a line (a-b), comprises: a gauge block positioned beneath said body, said gauge block having an upper surface defining a linear array of gauging apertures having a configuration corresponding to said linear array of said mounting apertures and arranged congruent to said line (a-b); and means engaging said gauge block for moving said gauge block upwardly toward said solid body so as to engage and receive said projections in the apertures thereof. The apparatus of claim 12 wherein said moving means includes means for fixing said gauge block in a predetermined position while said body is withdrawn from said loading station by said robotic arm. The apparatus of claim 12 wherein said gauge block is initially positioned remote from said loading station, said positioning means further comprising means for advancing said gauge block to said loading station. The apparatus of claim 12 wherein said solid body includes an upper surface opposing said support surface, said apparatus further including means overlying said gauge block for restraining the upper surface of said solid body against movement away from said gauge block as said gauge block engages said solid projections. The apparatus of claim 15 further comprising means located below said gauge block for pushing said gauge block with said projections engaged therein, from a first position upwardly to a second release position adjacent said loading station, where said solid body is freed for upward withdrawal by said robotic arm. The apparatus of claim 12 wherein said gauge block is positioned beneath said loading station, said apparatus further comprising a shuttle surrounding said solid body for containing and guiding said solid body during engagement with said gauge block and subsequent upward presentation to said loading station. The apparatus of claim 17 wherein said shuttle comprises: a moveable latch arm having a body engaging member adjacent one end thereof for engaging the upper surface of said solid body; means including a follower plate engageable with said gauge block for pivotably mounting said latch arm so as to bring said engaging member into and out of engagement with the upper surface of said solid body; cam means located adjacent said latch arm; and a camming surface on said latch arm engageable with said cam means to pivot said latch arm during upward movement thereof. The apparatus of claim 18 wherein said follower plate comprises a plate member defining a projection receiving aperture, and said latch arm comprises an outwardly extending projection received in said plate member aperture and pivotably engaging said plate member. An apparatus as claimed in any one of claims 9 to 19 wherein the solid body is an electrical connector having at least two of said linear arrays of projections constituted by parallel spaced-apart linear arrays of terminal portions; said mounting surface including two parallel spaced-apart linear arrays of terminal-receiving apertures having configurations corresponding to that of said linear array of said terminal portions; and wherein a track extends between a source of electrical connectors and said loading station having two spaced-apart terminal-receiving slots defined between first and second outer track walls and an intermediate track wall, respectively, at least one of said track walls having an upper surface for contacting said support surface of said electrical connector, each slot receiving one of said linear arrays of said terminal portions; and means is provided for loading a plurality of electrical connectors on said track. The apparatus of claim 20 wherein said straight reference surface includes an accurately dimensioned linear array of terminal receiving and straightening recesses formed in said track wall.

Inventors: STENSTROM, ERIC J., WOLYN, JOSEPH, WRIGHT, STEVEN F.
Applicants: MOLEX INCORPORATED
Application year: 1986
Main classification: H05K13
IPC codes: H05K3, B23P19, H05K13, B25J17, B25J19, H01R43