Selective Chip Pickup Apparatus For Multiple Feed Bowls

Abstract

A mechanical and pneumatic chip pickup apparatus employs a controllable vacuum manifold for selectively feeding vacuum or positive fluid pressure to vacuum pencils carried by an indexed, rotatable eight-position flexing pencil arm spider assembly. An oscillating depressor spider is coaxially positioned above the rotatable pencil arm assembly and adjustable depressor elements cooperate with preset pencil selectors atop each pencil arm to force the rotating pencil arm assembly at each index position to deflect into only designated feed bowls.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a mechanical and pneumatic pickup and transfer apparatus and more particularly, to an apparatus for selectively transferring minute semiconductor chips between circumferentially spaced stations for subjecting the same to multiple processing steps.

2. Description of Prior Art

Much electronic equipment includes minute electronic components in chip form which in turn during their manufacture require the movement of such devices between stations for processing and/or testing and inspection. In the past, electronic chips or like components have been picked up individually from a single feed bowl and moved from the feed bowl to some other part of the apparatus in the nearby vicinity for processing etc. There may exist a requirement for multiple feed bowls to maintain maximum handler through put. However, with some chip part numbers, small odd quantities may require only two or even one feed bowl, since the feed bowls will not feed efficiently unless maintained at proper operating supply levels. With this variable bowl requirement, it is further mandatory that a rapid positive approach be instituted to switch from single to multiple bowl requirements of varying number by a machine operator with little technical experience or minimum mechanical aptitude. The provision of a chip handling system allowing change in requirement of the number of bowls introduces three primary problem areas. The vacuum pencil or other means for physically removing the individual chip from a given bowl for transfer thereof to another station of the apparatus must not enter any bowl but its designated one. In order not to disturb the chip orientation in a selected bowl during pencil positioning, vacuum must be induced to the pencil just prior to the pencil moving upward from the selected bowl station. Further, a loaded pencil must maintain a constant vacuum condition upon leaving its designated bowl until it reaches a sort station whereupon the chip leaves the vacuum pencil by cessation of vacuum or by application of positive fluid pressure to discharge the same under force.

SUMMARY OF THE INVENTION

This invention is directed to a multiple bowl chip handler which includes an eight-position pencil arm assembly in the form of a spider carrying four pairs of pencils, each located 180.degree. apart. Deflectable arms carried by the rotatable spider, support a pencil at their ends, to which is selectively applied vacuum or positive fluid pressure. The pencil arm spider is indexed 45.degree. from station to station. One, two or four bowls underlie adjacent arms and the apparatus employs a four-track adjustable manifold together with adjustable pencil actuation for selectively picking up chips from one, two, or four bowls and transferring the same. Atop each pencil arm is a pencil selector preset to four conditions, the selectors being machined as right or left, with two rights always followed by two lefts. The deflectable arms are actuated by an eight-position spider which does not rotate but reciprocates vertically and has manually adjustable depressor selectors on each arm for contacting the pencil selectors and flexing the pencil arms selected.

A stationary vacuum manifold assembly provides a set of four manifold tracks, one for each pair of flexing pencil arms. The pencil arms are fluid connected to the manifold sensing ports in the hub with steady state vacuum, vacuum interrupt, and positive fluid pressure, being produced at the feed bowl stations by manually setting a pair of vacuum control shafts or valves at one of four different positions, and by means of an encoder synchronized to spider indexing. The positive pressure causes chip blow off at a given sort station.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial schematic, partial sectional, elevational view of the pneumatic multiple bowl chip handler apparatus of the present invention;

FIG. 2 is a partial fragmentary, top plan view of a portion of the apparatus shown in FIG. 1, partially in section, illustrating the major components of the apparatus;

FIG. 3 is a top plan view of the stationary manifold disc forming a portion of the apparatus;

FIG. 4 is a top plan view of the stationary manifold plate which underlies the stationary manifold disc of FIG. 3 and is coupled thereto;

FIG. 5 is a perspective view of one of the pencil arm selectors of the present invention;

FIG. 6 is a perspective view of one of the adjustable depressor selectors carried on each depressor spider arm;

FIG. 7 is a top plan view of the depressor selector shown in FIG. 6;

FIG. 8a through 8g are various sectional views and an end view of the stationary manifold assembly with the number one manifold valve in a selected position;

FIGS. 9a through 9g are sectional views and an end view of a portion of the manifold assembly illustrating the number two manifold valve in a selected position;

FIG. 10 is a graphical illustration of the adjustment positions of the various adjustable components of the chip handler apparatus of the present invention for single and multiple bowl modes.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1 of the drawings, the principal components of the multiple bowl chip handler apparatus of the present invention comprise stationary table 10 which supports stationary manifold present 12 which is annular in form, and through the center of which passes, in concentric fashion, a rotatable and indexable flexing pencil arm spider assembly 14 and a reciprocating, but nonrotatable, depressor spider assembly 16. The depressor assembly 16 is reciprocated in the direction of arrows 18 by means including drive motor 20, speed reducer 22, which in turn is coupled via indexer 24 to the rotatable, flexing, pencil arm assembly 14.

The table 10 may in fact comprise a cabinet of which only the top panel 26 is shown, the panel being apertured at 28 to receive the indexing and reciprocating drive components which extend upwardly from indexer 24 and reducer 22. These elements, along with the drive motor 20, are carried by the cabinet table and supported therein (by means not shown). The drive shaft 30 extends between and couples drive motor 20 to the reducer 22. The indexing drive connection may take the form of a keyed drive shaft 32 being provided with one or more projections 34 which are received within a respective notch 36 formed within the lower end of the rotatable vacuum manifold hub 38 forming one component of the indexable, flexible pencil arm spider assembly 14. In this respect, the annular stationary manifold 12 comprises a lower annular plate 40 which underlies the somewhat thicker, but smaller diameter, stationary annular manifold disc 42. Manifold disc 42 is flanged at 44 and its inner end defines the cylindrical bearing surface 46 which receives the projecting portion 48 of the vacuum manifold hub 38. The flanged portion 44 of manifold disc 42, in this respect, is sandwiched between the stationary manifold plate 40 and the rotating hub 38. The flexing pencil arm assembly 14 further includes, at its upper end, a rigid spider 49 defined by fixed arms 51 which acts to support flexible spider arms 50 on the underlining rotatable vacuum manifold hub 38. All of these members are readily formed of metal along with an intermediate annular block 54 which separates the upper and lower flexible arm members 56 and 58. Arm members 56 and 58 are preferably formed of spring steel and are coupled together at their outer ends by block assembly 60, the blocks being vertically apertured to receive individual vacuum pencils 62, FIG. 1 which are fixedly held thereby. Arms 56 and 58 flex appropriately with the block assembly 60 and its pencil 62 being biased upwardly by coil springs 64. One end is fixed to the outer end of the radially projecting arm 51 of rigid spider 49 by pin 66, and the other end coupled to the block assembly 60 by bolt 68.

Vacuum pencils are in themselves well developed, and constitute means for applying vacuum pressure at the extreme tip end 70 (preferably in the form of a hollow tube) with the vacuum pressure being provided to block assembly 60 through a flexible hose 72 or like tube whose inner end is threaded to annular block 54 by an individual threaded fitting 74. In this respect, the manifold hub 38 carries circumferentially spaced, vertical bores such as 76, having sensing ports such as 78 at varying radial positions, the bores being coupled in turn to respective horizontal passages 80 carried by the annular block 54 which then terminates at respective fittings 74 for opposed radial arms. Thus, vacuum pressure or positive pressure applied to the various vertical passages, such as 76 of the rotatable vacuum manifold hub is delivered to associated pencils 62 at the circumferentially spaced locations defined by the eight flexing pencil arms of assembly 14. A bearing lock-nut 33 on the upper end of shaft 32 accurately fixes the rotatable spider assembly 14 to the keyed drive shaft 32 to insure rotation about true center.

Shaft 32 is bored centrally to define an opening through which projects, in a coaxial manner, a reciprocating depressor spider assembly support and drive shaft 82. As mentioned previously, shaft 82 does not rotate, but does reciprocate in the manner indicated by arrow 18 by cam means (not shown) such that limited up and down motion is given to the depressor spider assembly 16. Assembly 16 constitutes a nondeflectable spider including a central hub portion 84 coupled to the end of shaft 82 by means of a threaded terminal end 86 which projects upwardly therethrough and receives a nut and lock washer assembly 88. Depressor spider arms 90 extend radially outwards, are similar in number, and are circumferentially spaced at 45.degree. (in the case of an eight-arm assembly) in a similar manner to the underlying deflectable spider arms 50. The outer end of each arm is bored and threaded at 92 to receive a threaded bolt 94 which carries a rotatable depressor selector 96. Each depressor selector 96 constitutes a disc-shaped base portion 98, FIG. 6, carrying circumferentially spaced, right angle, color coded sectors 102, 103, 104, and 105 of irregular cross-sectional configuration. The larger of oppositely oriented sectors 102 and 104 have internal and external surface recesses at 107 and 109 respectively.

In this respect, each depressor selector 96 is positioned on a reduced diameter terminal portion 108 of bolt 94 which extends downwardly from an enlarged diameter portion 110. A washer 112 maintains the base portion 98 on the bolt but allows adjustable rotation of the depressor about the axis of bolt 94. A coil spring 114 is compressed between the outer end of arm 90 and the back of the depressor selector 96 thus spring biasing the depressor selector into contact with washer 112. The periphery of depressor 96 of the disc-shaped depressor base 98 carries color coded notches 100 at various positions along its periphery, and a detent assembly consisting of a cantilevered spring 116 and a detent element 118 extends downwardly from the extreme outer edge of arm 90 in such a manner that the detent element 118 is spring biased against the periphery of disc 98 to seat in one of the notches 100 for locking the depressor selector at a selected angular position corresponding to the mode of operation desired for the chip handler.

As mentioned previously, the rotary position of each depressor selector 96 is set to correspond to a selective preset position of a corresponding pencil selector 106 carried by each of the rotating deflectable spider arms assemblies 50. Unlike the indexed flexing pencil arm assembly 14, each of the depressor selectors remain at a preassigned station, for instance, the right hand depressor selector 96 (shown in FIG. 1) overlies feed bowl 120 while the left hand depressor selector 96 may, in fact, overlie an inspection station 122, 180.degree. therefrom. One pencil selector is shown in FIG. 5 and constitutes a base portion 124 which includes offset holes 126 for receiving mounting pins 127 carried by block assembly 60 to allow adjustment of each identical pencil selector 106 at various angular and radial selected positions with respect to mounting block 60. At opposite ends of selector 106, there are upwardly projecting end surface extensions 128 and 130 which are prism-shaped and of a configuration specifically adapted to cooperate with the various sector projections 102, 103, 104 and 105 projecting downwardly from the base portion 98 of each depressor selector 96. The outer face of sector projection 128 is color coded yellow. The mounting holes 126 of the pencil selector are longitudinally and radially offset so that by rotation of the same 180.degree. the various projections 128 and 130 are both radially and angularly offset with respect to the overlying depressor assembly insofar as the vertical machine axis defined by shaft 82 is concerned. Screws are employed for fixing each pencil selector at a preset position on its block 60.

An important aspect of the invention resides in the method of selectively applying to the individual pencils 62, both vacuum and positive fluid pressure either intermittently or continuously as desired. This is especially difficult since the flexing pencil arm assembly 14 is being indexed from station to station whereupon, when each of the flexible arm assemblies 52 underlie the respective arms of the oscillating depressor assembly 16, the pencils carried by the arms are deflected (if selected) into immediate adjacent position or contact with the various bowls carrying the chips to be transported.

The table 10 supports the stationary manifold assembly 12 which includes the manifold plate 40 and the somewhat thicker manifold disc 42. Referring to FIG. 4, the manifold plate 40 constitutes an irregular metal casting or machined part including a radially projecting portion 138 terminating in an outer flattened surface 140. Three bores extend inwardly therefrom at 144, 146 and 148. A first radial groove or track 150 of rather narrow width in the form of a rectangular recess extends circumferentially a distance of approximately 180.degree., from a point defined by the inner end of bore 144. An extension 158 of the same track at the same radial position extends circumferentially in the opposite direction approximately 90.degree. from a point at the inner end of the right hand bore 148, FIG. 4. Bore 146 extends inwardly a slightly greater distance and opens up into an intermediate track or recess 154 which includes a rather large surface area portion 154a extending clockwise in a circumferential direction slightly in excess of 180.degree., a smaller circumferential portion 154b over a surface area of approximately 45.degree. and terminates in a narrow groove portion 154c of approximately the same circumferential length. A large central opening 156 is provided to receive the flanged portion 44 of the thicker manifold disc 42. A small, thin sectorlike recess 152 is sandwiched between the opening 156 and intermediate recess section 154b. Bore 144 is coupled to a source of positive fluid pressure for "blow off" or steady state vacuum. Bore 146 is fluid coupled through tube 155 to steady state vacuum pressure, and bore 148, through tube 157 to vacuum interrupt. The application of positive fluid pressure, steady state vacuum pressure, and vacuum interrupt pressure via tubes 153, 155, and 157 is controlled by a photoelectric encoder 11, FIG. 1, which carries a cyclically driven encoder disc or the like (not shown). The disc is driven from speed reducer 22 via drive shaft 13 correlated to indexer rotation. Pneumatic logic 15 for valving tubes 153, 155, and 157 is directly controlled by electrical output signals from encoder 15 via cable 17. Manifold disc 42 is positioned upon and overlies manifold plate 40 with the large recess 154 in fact underlying three tracks carried by manifold disc 42, surface recess section 154b underlies two of the same, while recesses 152 and 154c underlie but single tracks of the manifold disc 42. The manifold disc 42 is fixedly and sealably positioned on top of the underlying manifold plate 40 with flange 44 received within opening 156 of plate 40. In this respect, the mainfold disc 42, as shown in FIG. 3, is oriented in the identical position in this FIG. that it occupied with respect to plate 40 when assembled in the manner of FIG. 1. A relatively large bore 158 of disc 42 has its axis aligned with the axis of recess 160 formed within plate 40, while enlarged bore 162 of the same disc overlies recess 163 of plate 40. With this in mind, it is easily seen how the disc and the plate are angularly oriented with respect to each other when assembled. The assembly may include coupling means at various positions as defined by coupling openings 165 formed within the lower plate 40 for physically locking the manifold disc 42 to the underlying plate. In this type of arrangement, the lower manifold plate 40 acts as the distribution means for the four radially spaced manifold tracks indicated at 164, 166, 168, and 170 on the upper surface 172 of manifold disc 42. Each of the radially spaced tracks 164 through 170 are associated with a particular pair of oppositely directed flexing arm assemblies 50 and are fluid coupled through sensing ports carried thereby. For instance, as shown in FIG. 1, the right hand pencil 62 is fluid coupled by manifold hub vertical passageways 76 and sensing port 78 to intermediate manifold track 168 while the imperforate surface portion of the manifold hub 38 overlies tracks 164, 166 and 170. Further, left hand sensing port 78 is coupled to recess 154a of plate 40 via passage 79. Hub 38, as shown in FIG. 2, is provided with four pairs of radially and circumferentially offset vertical bores of which the two outermost bores 174 and 176 are shown, exposed by breaking away a portion of overlying spider forming components of assemblies 14 and 16. In this respect, the outermost manifold track 164 comprises essentially a series of circumferentially spaced perforations 178 while some of the inner most track 170 constitutes, for the most part, discontinuous curved slots 180, 180a, 180b. However, on either side of the enlarged surface opening or recess 182, for each track there are individual perforations 192 and 184. Recess or opening 182 is unconnected to the underlying manifold plate 40 but, the manifold disc 42 carries a radial bore 186 which opens up into recess 182 at 188 the outer end of this bore being exposed to atmosphere via coupling 189. Thus, the station just prior to the recess 182 is the discharge or sort station. When the hub sensing port, associated with the arm radially in line therewith, moves into overlying position with respect to hole 192, positive pressure replaces the vacuum within the pencil only when encoder activates the switch forcibly discharging the chip (not shown), which overlies the open end of the pencil tube 70 at the sort station. Again, for proper operation, portions of the innermost manifold track 170 are fluid coupled to other portions of the next radially adjacent track 168 by radial slot extensions as at 190, 190a and 190b.

Vacuum pressure is selectively applied to the individual pairs of pencils, during rotation in complete cycles, either continuously, i.e., as a steady state vacuum, or vacuum interrupt for certain portions of each cycle. The selectivity is achieved by the presetting of vacuum shafts 1 and 2 for controlled application and distribution of vacuum for all four manifold tracks through the stationary manifold assembly 12 and by means of the encoder 11. The vacuum interrupt condition is generated by an encoder controlled valve inducing either steady state vacuum or no vacuum. All circular openings 178 are always exposed to steady state vacuum when the apparatus is in operating mode. Referring to FIG. 2, vacuum valve Number 1 is identified generally at 200 while vacuum valve Number 2 is displaced approximately 45.degree. therefrom and is identified at 202. Each vacuum valve includes a rotatable vacuum shaft. The rotatable vacuum shaft 204 is received within bore 162 of manifold disc 42 while shaft 206 of the Number 2 vacuum valve 202 is received within bore 158. Projecting pins 208 near the outer end of each shaft allow the operator to physically rotate the valve within its respective bore to change the flow conditions for the stationary manifold assembly. By reference to FIG. 1, the Number 1 vacuum valve shaft 204 is received within bore 162, extends the length thereof, and is provided various radially extending bores which are fluid coupled by an axial bore 210 seen with greater particularity in FIGS. 8a through 8g and extending partially the length thereof. At selected angular and longitudinal positions, are radial passages for selective alignment with the manifold track passages for tracks 164 through 170 within manifold disc 42 allowing delivery of the vacuum pressure to these tracks from the supply as defined by the fluid passages or recesses, carried by the manifold plate 40. In this respect, by referring to FIG. 8a which constitutes a radial section of the manifold assembly 14, the relative positions of the radial passages at b, c, d, e, and f are readily defined. Referring next to FIG. 8b, valve shaft 204 is provided with a single radial bore 210 which is shown in this position as being aligned with circular hole or vertical bore 184 of the disc 42 corresponding to track 170 of the manifold assembly. FIG. 8c illustrates another radial section in which the shaft 204 is provided with a pair of right angled radial bores 214 and 214a, bore 214, at this rotary position of the shaft 204, being aligned with bore 184 associated with track 168 of the manifold assembly. At location defined by radial section d and illustrated in FIG. 8d, a single radial bore 216 is in alignment with vertical bore 184 associated with track 166 of the manifold assembly. Radial section FIG. 8e illustrates the employment of a through bore defining bore sections 218 and 218b and a right angle section 218a. In the present case, radial bore 218 fluid connects longitudinal bore 210 to opening 184 of track 164. At radial section f, shown in FIG. 8f, the manifold disc 42 carries a small vertical bore 222 opening up into exposed recess 158 of the manifold plate 40 and the shaft 204 carries paired through bores defining radial bore sections 220, 220a, 220b and 220c. The radially projecting pins 208 adjacent the outer end of the shaft 204 may be color coded but the shafts preferably are V shaped at the ends with right angle grooves 209 also provided, as indicated with red, blue, and yellow color designations, to facilitate operator rotation of the valve to a position which is determined not only by the number of bowls selected for use, but correlated to similar color codings on the preset pencil selectors 106, and the adjustable depressor selectors 96.

Vacuum valve Number 2 at 202 is similarly constructed and reference may be had to FIGS. 9a through 9g inclusive which illustrate the valve in one of its adjusted positions and shows the flow path for the applied vacuum to the same. In this case, in addition to the Number 2 valve shaft 206 being provided with a longitudinal bore 240, which extends the majority of its length but is completely closed at both ends, there is provided upper and lower longitudinal slots or recesses 242 and 244, located circumferentially opposite each other and extending a length defined by manifold tracks 164 through 170. Further, as seen in FIG. 9e, the full periphery of the shaft 206 is relieved and in FIG. 9c, the majority of peripheral surfaces, in excess of 180.degree. is relieved. The underlying manifold plate 40 is provided with three separate fluid passageways or recesses; radially innermost passage 152 and passages 154c and 158, radially beyond the same in that order. The manner in which fluid is selectively delivered to the four tracks 164 through 170 from the selected position shown and also the possible variations, may be readily apparent by reference to the radial sections FIGS. 9b through 9f inclusive. In this respect, referring to FIG. 9b, the longitudinal bore 240 of shaft 206 has a single radial bore 246 extending therefrom which, in the position shown, is cut off from opening 180b partially defining track 170. This track is, however, in fluid communication with longitudinal surface recess or slot 242 of valve shaft 206 and completes a fluid circuit to vertical hole or bore 178 in manifold disc 42.

In FIG. 9c, again the valve shaft 206 is provided with a single radial bore 254 extending from longitudinal bore 240 which, in the position shown, is isolated from longitudinal slot 242 within manifold disc 42 although, at this time, manifold plate recess 152 is in fluid communication with the lowermost longitudinal slot or recess 244 of the valve shaft 206, through bore 243, In FIG. 9d, there extends, in opposite directions, radial bores 248 and 248a from the longitudinal bore 240 within shaft 206 but in the position shown, both bores are cut off from fluid communication with the slot 193 partially defining track 166 of the manifold assembly. However, the longitudinal peripheral recess 242 is in fluid communication with track 166 and also tracks 164 and 170.

At manifold position defined by the sectional view FIG. 9e, a complete peripheral recess, defined by reduced diameter, outer surface portion 250, illustrates the continuous fluid coupling of bore 178 associated with track 164 to both longitudinal recess passages 242 and 244 of shaft 206.

Delivery of fluid pressure to longitudinal bore 240 is achieved at manifold radial location defined by sectional view FIG. 9f, in which case shaft 206 carries four right angled vertical bores 258, 258a, 258b and 258c such that, in any of the four selected positions longitudinal bore 240 will be in fluid communication with fluid delivery passage 158 associated with the underlying manifold plate 40 via vertical bore 250 of the overlying manifold disc 42. Again, by reference to FIG. 9g, the V shaped relieved surfaces on front end of valve disc 206 are color coded to indicate the mode position of the Number 2 valve which corresponds to that of the Number 1 valve shaft 204.

A schematic representation of the mode adjustments and the effect of the same may be seen visually by reference to FIG. 10. In FIG. 11, the manifold assembly 12 is shown schematically in flat rectangular form rather than as an annular disc. The number two vacuum valve 202 is illustrated as being just to the left of the number one vacuum valve 200 and the first, second, third and fourth tracks are identified at 164, 166, 168 and 170, respectively. For all four tracks, the large valve manifold assembly recess 182 allows the application of atmospheric pressure after the sort station. The indexer stations 1, 2, 3, 4, 5, 6, 7, and 8 are identified from right to left, both in association with the stationary manifold assembly 12, the adjustably positioned pencil selectors 106 of the rotatable flexing pencil arm assembly 14 and the adjustable disclike depressor selectors 96. Further, for single bowl mode, two bowl mode, or full four bowl mode operation, the positions of respective number one and number two valve shafts 204 and 206 are shown corresponding to those set forth in the following table: ---------------------------------------------------------------------------

Pencil Arm Depressor Vacuum Manifold Mode Selector ASM Shaft No. 1 Shaft No. 2 __________________________________________________________________________ Single Bowl Yellow Red Red Red Double Bowl Yellow Blue Blue Blue Four Bowl Yellow Yellow Yellow Yellow Skip Yellow Green as is as is __________________________________________________________________________

It is necessary therefore to first preset the pencil selector positions at all stations to the table, in which upstanding end sections 128 and 130 vary in position both angularly and radially by rotation of the same about the eccentric axis. Thus four independent positions, shifted angularly by 22 1/2 degrees and radially by full rotation of 180.degree. are provided. These positions are then correlated by manual rotation of depressor selectors for single bowl, two bowl, and four bowl for each station, along with rotation of the color coded valve shafts 204 and 206 to the positions indicated to the right in FIG. 10. The instructions for accomplishing the same are simply and easily defined by the above table.

Depending upon feed bowl requirements, the designated color code is selected for vacuum shafts Number 1 and Number 2 by reference to the feed bowl operation table. Two vacuum conditions may be induced at each feed bowl station such as steady state vacuum or vacuum interrupt as desired. These conditions will always occur at all bowl stations in the stationary four track manifold and are transmitted to the sense ports in the rotating vacuum manifold hub assembly.

After each pencil receives its chip pickup through vacuum interrupt, full vacuum will be maintained throughout the machine cycle under the proper selection of the number 1 and number 2 vacuum valves until the sort station is reached (in this case, station 8) whereupon the sense port receives positive pressure from stationary manifold recess 192, and chip blow off occurs directly by electropneumatic means via encoder 11. The precise phasing of vacuum interrupt is done by means of the photo encoder 11 which controls all machine cycle functions and is driven by the input drive shaft 30.

In the operation, reference to the feed bowl operation code set forth in the table, indicates that, when a single bowl mode is required, the machine operator positions Number 1 on hub 38, corresponding to a given arm, to Number 1 indexer station and dials the depressor selector 96 at bowl 1 (station 1) to red, matching all possible yellow areas on selector positions of the flexing pencil arm assembly 14. The depressor assemblies at the aligning, contact and sort stations (stations 5, 6, 7 and 8) are dialed in a similar manner insuring pencil motion up and down at every station so selected. Since bowl stations 2, 3 and 4 are not used, the depressor selector at these stations are dialed to the green color area, in the yellow area of any preset pencil selector position, insuring a skipping of the depressor ASM action, resulting in no pencil displacement into bowls 2, 3 and 4. In addition, the vacuum shaft 204 and 206 for Number 1 and Number 2 valves respectively of the stationary four track vacuum manifold assembly 12 are positioned accordingly to the chart and by reference to FIG. 11, the number 2 shaft 206 is dialed to the red while the number 1 shaft 204 is dialed or rotated also to the red position. The single bowl mode will always expose all sense ports, that is vertical passages or bores 78, 176 and 174 of the rotating vacuum manifold hub 38 to vacuum interrupt conditions as they rotate into bowl station number 1 and upon leaving, sense ports on all four tracks of the stationary vacuum manifold assembly will maintain a steady state vacuum condition. This insures fixed chip positioning on all pencils throughout the indexing cycle until the sort station is reached. Machine operation insures indexing 45.degree. from station to station and subsequent depression of the rigid spider arms 90 causes selective depression of the individual pencils, depending upon the position of respective pencil and the depressor selectors.

Similarly, in the double mode bowl mode, the color blue defines the depressor assembly motion at bowl stations No. 1. and No. 2 only with a parallel vacuum interrupt occuring at every second machine cycle. With a "green" condition on the depressor selectors in bowls No. 3 and No. 4, pencil motion will remain stationary and above these bowl areas. To maintain a chip on each pencil after leaving vacuum interrupt conditions, vacuum shafts No. 1 and No. 2 must be positioned as indicated by the table. Specifically, both vacuum shafts 1 and 2 should be in the blue color code position as evidenced by FIG. 10.

Under four bowl operation, the yellow of the depressor selector at bowl stations No. 1 through 4 are matched with the yellow on each of the four different pencil selector positions. All bowl operations are totally illustrated in FIG. 10 with the pencil selectors 106 being positioned properly with respect to depressor selectors 96 for each of the indexer stations. Further, the vacuum shafts 204 and 206 for vacuum valves 1 and 2 are positioned to yellow as indicated in the chart which results in a vacuum interrupt condition at all four bowl stations simultaneously and is always followed by a steady state vacuum condition from the bowls up and to the sort station. It is self-evident that only at every fourth machine cycle can the parallel pickup motion occur at the bowl areas. This feature provides maximum time allowance for chips feeding properly into the bowls. As is further evidenced from viewing FIGS. 8a through 8g and FIGS. 9a through 9gthe selective delivery of vacuum under vacuum interrupt conditions and steady state vacuum conditions by selective rotation of vacuum valve shafts 204 and 206 is readily apparent due to the various cooperating fluid passages formed within the rotating valve shaft, the associated manifold disc 42 receiving the same and the underlying stationary manifold plate 40. serviceability The present invention constitutes a marked improvement since it is beneficial in at least three important areas, serviceability and versatility, higher machine throughout and optimum vacuum performance. With serviceability, lower operator skills are possible with no special tooling requirements when switching bowl requirements of the machine. In addition, the time required for this phase is estimated at three minutes maximum. Secondly, since the two kinematic motions of the drive system, namely rotation and lift are divorced from one another during the complete machine cycle, lower peak torque requirements are reduced resulting in higher machine throughout and increased life of the clutch-break drive unit. Finally, the compact packaging of the stationary vacuum manifold assembly with minimum tubing line lengths acts in conjunction with the four perforated vacuum tracks resulting in a more rapid pneumatic response and minimum drag resistance during the start phase of rotation.

Claims

What is claimed is:

1. An apparatus for handling parts, comprising, in combination: a first rotatable spider assembly having uniformly spaced, radially extending, flexing arms, part holding means carried by each arm and depending therefrom, a second nonrotatable, reciprocating spider assembly mounted coaxially above said rotatable spider assembly and having rigid arms corresponding to said first rotatable spider assembly, means for indexing said rotatable spider assembly from station to station defined by the radially extending rigid arms of said second reciprocating spider assembly, means carried by at least one of said spider assemblies for causing flexing of said rotatable spider assembly arms during angular alignment between said spider assemblies and movement of said second overlying spider assembly towards said underlying first rotatable spider assembly.

2. The apparatus as claimed in claim 1 wherein said holding means comprises a vacuum pencil for holding parts in depending fashion therefrom by the application of pneumatic pressure thereto.

3. The apparatus as claimed in claim 1 wherein said means for causing flexing of selected arms of said first shiftable spider assembly comprises a shiftable depressor selector mounted underneath the outer end of each arm of said second, reciprocating spider assembly and corresponding shiftable upstanding pencil selectors mounted on the outer end of respective arms of said first rotating spider assembly and in the path of associated reciprocating depressor selectors.

4. The apparatus as claimed in claim 3 wherein said shiftable depressor selector comprises a disc including a plurality of circumferentially spaced, sector-shaped extensions of irregular configuration extending downwardly therefrom at varying radial positions and said shiftable pencil selectors comprising a rotatable, U-shaped member mounted on the upper surface of each flexing arm for angular adjustment about an eccentric axis said ends forming projections having configuratory and radial positions compatible with the sector shaped projections carried by the rotatable depressor selector and adapted for selective movement into engagement therewith.

5. The apparatus as claimed in claim 4 further comprising a plurality of peripheral notches carried by each rotatable depressor selector disc, one for each significant angular adjustment position of said rotatable depressor selector, a cantilever spring having one end fixed to the outer end of each arm of said second spider assembly and a detent element carried by each spring and spring biased within a selected peripheral notch.

6. The apparatus as claimed in claim 2 further comprising means for selectively applying steady state vacuum pressure, vacuum interrupt or positive pneumatic pressure to said vacuum pencil for maintaining engagement between the part and the pencil during transport but allowing part blowoff at a given station.

7. The apparatus as claimed in claim 6 wherein said means for applying vacuum and positive pneumatic pressure to said pencil comprises; a stationary manifold assembly underlying said indexable first rotatable spider assembly, and wherein said first indexable spider assembly includes a manifold hub rotatable therewith and having sensing ports for carrying fluid passage and movable into alignment with fluid passages carried by said stationary manifold, and means for fluid coupling the individual pencils carried by each arm to said sensing ports within said rotating manifold hub.

8. The apparatus as claimed in claim 7 wherein said stationary manifold assembly further comprises means receiving positive pneumatic pressure.

9. The apparatus as claimed in claim 7 wherein said stationary manifold assembly and said manifold hub comprise coaxially positioned annular members, said stationary manifold assembly includes a plurality of fluid passages defining individual radially spaced pneumatic tracks, said rotary manifold hub carries sensing ports and paired, oppositely directed arms equal in number to the tracks carried by said stationary manifold assembly with said sensing ports adapted to rotate about paths concentric with respective tracks.

10. The apparatus as claimed in claim 9 further comprising at least one vacuum valve carried by said stationary manifold assembly for selectively coupling vacuum pressure to said manifold tracks.

11. The apparatus as claimed in claim 9 wherein said stationary manifold assembly comprises an underlying manifold plate and an overlying manifold disc, cooperating fluid passages in both said stationary manifold plate and in said stationary manifold disc, means carried by said stationary manifold plate for coupling said passages to a plurality of individual vacuum supply lines, radial bores carried by said overlying stationary manifold disc, rotatable vacuum valve shafts carried within said bores, and fluid passage means carried by said vacuum shafts for selectively coupling the fluid passages including those defining said vacuum tracks of said stationary manifold disc to the fluid passages within said stationary manifold plate.

12. The apparatus as claimed in claim 11 further comprising fluid passage means carried by said stationary manifold disc for sequential fluid communication with all of said sensing ports carried by said rotatable manifold high and means for fluid coupling said passage means to the atmosphere for releasing fluid pressure to the individual pencils after part blowoff at a given station.

13. The apparatus as claimed in claim 12 wherein the exposed ends of said rotatable vacuum shafts carried by said stationary manifold assembly, said rotatable depressor selector, and said rotatable pencil selector are correspondingly color coded to facilitate selective multiple bowl operation of said part handling apparatus.