US 3583548 A
Abstract available in
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Description (OCR text may contain errors)
United States Patent 3,351,198 11/1967 Wyman 3,414,110 12/1968 Ellis......... 1,594,821 8/1926 Dulligan......................
Primary Examiner-Edward A. Sroka A!torneysHanifin & Jancin and Av Sidney Alpert Armonk, N.Y.
ABSTRACT: Apparatus for high speed accurate handlin miniature articles includes a feeder that conve the articles substantially simultaneously to a pi sector of a rotatable transfer wheel having peripherally opening pickup pockets is disposed in a recess in the feeder at the pickup station for receiving the articles. This permits each of numerous pickup pockets to remain ex uring a portion of the wheels rotation to ensure that each pocket receives an article. The articles are carried with at least a portion of their outer surface in contact with a wall or walls of the pickup pocket so that they are precisely located with respect to the wheel. This enables subs electrical tests, upon the articles during transport.
d m n a 70 6 7 wmwl w /7 :1 I 83 0O 9EQW 9 E 6 9 1 R Bi w mmm A m M l m In N m M N m M m a m M m A .l U .IP H L M M C s m D u ME N s m MB T m A .Q n 1 n F m m m T m R m m WM m m 0 W m RmB F I m. U01 T s r. un o 1. U D mm N5 NT. m mu7 U m m m mm H mm m PRC Sm "w AAS UIIF 4 l 1]] l as, 4 2 0 6 H U 5H5 U 2 PATENTED JUN 8m: 3.583548 sum 1 or 6 INVENTOR ROBERT H. CADWALLADER BY 0 7 M ATTORNEY PATENTEU JUN 8 I971 SHEET 2 OF 6 PATENTED JUN 8197i SHEET 3 BF 6 m QE PATENTED Jun 8 I97! SHEET 5 [IF 6 FIG.
APPARATUS FOR HANDLING MINIATURE ARTICLES BACKGROUND OF THE INVENTION This invention relates to the field of conveying apparatus and more specifically to improved conveyors for handling miniature articles in a manner to permit their processing while carried on the conveyor.
Small articles such as miniature ferrite cores of toroidal or similar shapes and miniature chips used to produce semiconductors, and the like, normally must be individually handled or conveyed during their fabrication. For example, miniature ferrite cores must be individually tested and sorted, and chips must be assembled and tested and sorted, or both.
In the specific case of miniature ferrite cores of the type used in computer memory systems (i.e., cores ranging from 13 to 30 or so mils in outer diameter), it is necessary to put all the cores individually through a series of electrical tests. In this regard, several types of prior art apparatus have been developed for handling the cores during testing and sorting. These prior art apparatus range from simple hand-operated devices, to machines that feed, test and sort cores automatically. The prior art machines are generally satisfactory when larger cores are tested, and when the number of cores to be tested is not particularly great and hence speed is not essential. However, the prior art machines suffer from several common deficiencies, including an inability to accurately handle and position the miniature cores at high rates of speed. What is meant by handling at high rates of speed is a machine throughput or transfer from input to output of at least 25 articles per second, or greater. In addition, other deficiencies of previous core handling apparatus involve a relatively great amount of down time required to change over from one core type to another, and general inaccuracy in handling and positioning magnetic cores. Also, certain equipment has been devised for individually handling semiconductor chips during their fabrication. While some success has been achieved in this regard, the semiconductor chip equipment also is limited by being relatively slow and inefficient in operation.
Accordingly, in general, it is an object of this invention to provide improved apparatus for handling miniature articles, with particular emphasis on overcoming the deficiencies of apparatus known to the prior art.
It is another, more specific, object of the present invention to provide improved apparatus that is capable of conveying miniature articles individually and at very high speeds, while achieving extreme accuracy in alignment of the articles during transport.
SUMMARY OF THE INVENTION In the preferred embodiment of the present invention there is provided conveying apparatus for miniature magnetic cores that includes a vibratory feeder into which a plurality of the cores are loaded for feeding to a pickup station. The feeder bowl has an arcuate recess in which is located a sector of a transfer means, which in the illustrated embodiment is a rotatable wheel having a plurality of peripheral pickup means. The pickup means are vacuum pickup pockets, and in the preferred embodiment the sector of the wheel located at the pickup station contains a plurality (at least two but preferably six) of these pockets for receiving cores from the vibratory feeder substantially simultaneously. This arrangement provides must faster pickup than is available in presently known miniature core (or other type device) handling apparatus. In the available apparatus, the cores or other miniature articles are presented in single file to some type of pickup means that receives each article individually. This serial or single file feeding presents a bottleneck and limits the throughput or speed of the prior art apparatus. In this regard, if a pickup means fails to pick up an article for some reason, it remains empty during the remainder of its cycle. This, of course, reduces efficiencies. On the other hand, in the apparatus of the present invention, each pickup means or vacuum pocket has available for pickup a plurality of cores, and thus while at the pickup station, each vacuum pocket is repeatedly capable of receiving and picking up a core. This permits faster rotation ofthe transfer wheel than an arrangement when only one core is available for pickup by each pocket.
In the embodiment, there is shown by way of exemplification, and not limitation, a test probe associated with each vacuum pocket. The probes are carried in a probe barrel or carrier that is mounted, along with the transfer wheel, on the output shaft of a stepping motor, and the barrel and wheel therefore rotate together. Also shown by way of illustration is a test station and a means for testing the cores as they are carried in the transfer wheel. It is to be understood however, that the present invention is directed to conveying apparatus and not to the probes and test station. That combination is described in greater detail, and claimed in copending application of Baker et al., Ser. No. 737681, filed June 17, I968.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of a preferred apparatus that uses the conveying means of the present invention;
FIG. 2 is an enlarged vertical sectional view taken substantially on the plane of the line 2-2 in FIG. 1;
FIG. 3 is a still further enlarged sectional view taken substantially on the plane ofthe line 33 in FIG. 2;
FIG. 4 is a sectional view taken substantially on the plane of the line 4-4 in FIG. 3;
FIG. 5 is a sectional view taken substantially on the plane of the line 5-5 in FIG. 3;
FIG. 6 is a sectional view taken substantially on the plane of the line 6-6 in FIG. 3; and
FIG. 7 is an exploded perspective view of portions of the transfer wheel and probe assembly of the exemplified apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENTS GENERAL DESCRIPTION FIG. I shows an overall perspective view of the preferred form of the apparatus that uses the present invention. The apparatus may be designated generally as an automatic core tester, and is denoted by reference numeral 20. The automatic core tester 20 comprises a horizontally disposed base 25 supported upon two leg assemblies 28 and 30. As will be seen, each leg assembly sits upon a pair of similar rubber feet 32 that are provided in order to isolate or damp vibrations. Each leg assembly 28 or 30 also houses certain electrical circuitry and includes various controls such as control switches 34 on leg assembly 28 and control switches 36 on leg assembly 30.
Mounted on the base 25 of the machine 20 are four major assemblies, a feed bowl support assembly 40, a feed bowl assembly 42, a core handling assembly 44 and a contact head assembly 46. The feed bowl support assembly 40 is provided for supporting the feed bowl, generally designated by reference numeral 50. A clamp 52 mounts the vibrator motor 54 of the feed bowl assembly to a support arm 56. The support arm 56 is mounted in turn upon an upright, generally L-shaped support member 58 which is in turn mounted upon base members 60 and 62. The base member 62 is slidably mounted on ways 64, and the base member 60 is slidably mounted in base member 62. In addition, the arm 56 is slidably mounted on support member 58. In this manner, X, Y and Z motion is available to accurately position the feed bowl 50. X-axis bowl adjustment knob 68 and Z-axis bowl adjustment knob 69 are visible in FIG. 1.
The feed bowl assembly 42 includes the aforementioned vibrator motor 54, the feed bowl 50 and in addition bowl stem 70. The feed bowl is a conventional vibratory feeder of the type well known to those skilled in the art. It has been modified, in the present machine 20, to have its bowl stem 70 and vibrator motor 54 above the bowl 50 rather than below as is usually the case. This relationship is desirable in order to have the feed bowl 50 as close as possible to the base in order to prevent cores from entering the vibrator 54.
The core handling assembly generally designated by reference numeral 44 includes a cam support arm 74, supported at its outboard end adjacent base 25 on an adjustable mount (not illustrated) to which an adjustment means 76 is connected. On the inboard end of the arm 74 there is mounted an overhead cam 78 that is provided for a purpose to be more thoroughly discussed hereinafter. Below the cam 78, and supported from below is a test probe guide ring 80, test probe harrel 82 and a transfer wheel 84, As will be explained later, the transfer wheel 84 and barrel 82 are mounted on the output shaft of a motor, not shown in this view, that is mounted below base 25. In FIG. 1, there is shown a portion 86 of the motor housing which also serves as a seat for core receiving accept and reject vessels, respectively 90 and 92. Associated with the core handling assembly 44 are a reject tube 96 and its support or mount 98, and an accept tube 102 and its support or mount 104. Also associated with the core handling assembly 44 are a pair of blow-off tubes 381 and 382 to be mentioned again below.
The contact head assembly 46 is, similarly to the feed bowl support assembly 40, movable in X, Y and Z directions upon ways. The contact head assembly 46 includes the contact head 120, carried upon an upright movable plate 124. The plate 124 is vertically adjustable by Z-axis adjustment knob 126, and is mounted upon ways 128 forming a portion of L-shaped support member 130. Support member 130 is adjustable in the Y direction by Y-axis adjustment knob 134, being movably mounted upon base support 140. Base support 140 is mounted upon ways 144 on the base 25 and is movable in the X direction by X-axis adjustment knob 146. Adjacent to the contact head 120 are four coaxial connector members 152. Also visible in the overall view of FIG. I is a transformer adjustment screw 156 and pressure gages 160, I62 and I64, all forming a portion of the fluidic operating and control system of the present machine. Also visible in FIG. I and comprising a portion of the fluidic control system is an electric-to-fluidic transducer 170 mounted on leg assembly 30.
CORE HANDLING ASSEMBLY Having now generally described the various assemblies of the machine 20, shown in FIG. 1, reference should now be had to FIG. 2 which is a vertical cross section through the core handling assembly 44, also encompassing portions of the feed bowl assembly 42 and contact head assembly 46. As previously mentioned, it will be noted that the motor 180 is mounted below base 25, with motor shaft 182 extending upwardly above base 25 through an opening 186 in the base. The motor 180 is connected to the underside of the base 25 by key 184 in keyway opening 186.
In order to mount the transfer wheel 84 and barrel 82 upon shaft 182 as previously mentioned, a support or mount member 188 having a body portion 190 and a supporting or flange portion 192 is fixed to the shaft. The aforementioned transfer wheel 84 encompasses, in the exemplified embodiment, several elements which may be seen not only in FIG. 2 but also for example in FIGS. 4 and 5. The mount flange 192, a platform 194, a pickup shim or plate 196, a clamp washer 200 and a clamp plate 204 essentially comprise the transfer wheel 84 but it could, if desired, have more or fewer elements. For example, flange 192 might be extended up and machined to provide the elements and function of the wheel, as will be explained later. In this embodiment, however, the platform 194 is seated upon the upper flat surface of the flange 192 and slip fit upon a pair of dowel pins 206 and 208 as will be seen for example in FIGS. 2 and 7. Also mounted on the dowel pins 206 and 208 are the pickup plate 196, clamp washer 200,
clamp plate 204 and the previously mentioned test probe barrel 82.
FIG. 7 is an exploded perspective view that shows the platform 194 to be an annular member having a pair ofpin receiving holes 210 and 212 for mounting the platform upon the dowel pins 206 and 208 respectively. The platform I94 also has a central opening 214 and a plurality of channels or grooves (20 in the exemplification) 220 that open to or communicate with the central opening 214 and extend radially outwardly, but terminate short of the periphery of the platform. The pickup plate 196 also is an annular member having a central opening 222, a pair of mounting holes 224 and 226 and, in the exemplified embodiment, 20 generally V-shaped notches comprise portions of vacuum pickup pockets 232 that open to the periphery of the plate, with each pocket being connected at its inner end by connecting slots 230 to an elongate hole 228 in plate 196. The washer 200 is a spherical, annular member that is provided for clamping plate 196, by means of clamp plate 204, tightly against plate 194.
It will be noted, especially in FIGS. 2, 4, 5, and 7, that each channel 220 in platform 194 is contiguous along at least part of its length with one elongate hole 228 and slot 230 in plate 196. Also, that the peripheral vacuum pickup pockets 232, together with slot 230, hole 228 and channel 220 comprise 20 vacuum channels or passages 240, formed in members 194, 196 and 200. The vacuum passages 240 from a central vacuum manifold 242 to the peripheral edge of the pickup wheel 84 and terminate in the 20 pickup means or vacuum pickup pockets 232. It will also be noted that the 20 vacuum pickup pockets 232 are equally spaced (every 18) about the periphery of the transfer wheel 84.
The vacuum manifold 242 is formed by a cutout portion 250 in the barrel 82 together with the annular openings 214 and 222 in platform 194 and pickup plate 196 respectively. The openings 252 and 254 in clamp washer 200 and clamp 204 respectively, and the outer periphery of an upper stem portion 256 of mount 188 complete manifold 242. The mount 188 includes four equally displaced passages or ports 258 that open to the manifold 242 and to a vacuum passage 260 within the motor shaft 182. This vacuum passage 182 is connected ultimately to a vacuum pump 262 shown schematically in FIG. 2 for example. Thus, it will be appreciated that when a vacuum is drawn by vacuum pump 262, the vacuum manifold 242 will operate to draw a vacuum through the 20 vacuum passages 240 forming, in effect, 20 equally spaced vacuum pockets or pickup means about the periphery of the transfer wheel 84.
As mentioned previously, the barrel 82 is mounted upon dowel pins 206 and 208 and hence rotates together with the transfer wheel 84 and its associated elements including wheel mount 188 as motor shaft 182 is rotated. In the exemplification, the motor 180 is a stepping motor that steps in 18 increments, since there are 20 vacuum pickup pockets in the transfer wheel 84. The barrel 82, as shown in particular in FIG. 7, has twenty vertical probe receiving chambers 270 comprising an upper flange with its openings 272, an exposed portion having channels 274 and a lower flange with its openings 276. In each probe receiving chamber 270 there is disposed a test probe assembly 280 that, upon reference to FIGS. 2 and 5, will be seen to include a probe housing 282, an insulating sleeve 284, a probe body 286, a probe tip 281 and an insert 288 insulated from the probe body and tip by a layer of insulation 290. Each probe housing includes an upper cam follower head 294. The housing 282 has a cutout portion 296 for receiving a probe return spring 298 that normally biases the probe housing upwardly within the barrel 82. The probe barrel 82 is mounted upon the stem portion 256 of mount 188 by a mounting nut 300 as is shown in FIG. 2.
In order to operate the probe assemblies 280, or to cause them to reciprocate as the motor shaft 182 and probe barrel 82 revolve, the previously mentioned cam 78 is mounted immediately above, and partly within an opening 302 in probe guide ring 80. The guide ring is seated upon the probe barrel 82 for preventing the test probes from rotating during their reciprocatory motion, that is provided by reciprocation means including cam 78 and return springs 298. The cam 78 is fixedly mounted immediately above the rotatable probe barrel 82 upon arm 74 by mounting nut 306. The cam 78 has a downwardly facing cam track or surface 308 against which the cam follower heads 294 ride in contact over a preselected portion of their rotation. As will be seen in particular in FIGS. 1 and 2, the cam extends over approximately 270 of the probe guide ring 80 and barrel 82, leaving a portion thereabove open for ease of extraction of the probe assemblies 280, if so desired. This provides a convenient way of removing defective or warn probe assemblies, i.e. merely by removing their spring 298 and lifting the assembly upwardly out of the probe barrel 82.
FEED BOWL ASSEMBLY One objective of the present invention is to individually handle magnetic cores at a high rate of speed and to enable operations such as tests thereon during their transport. in this regard, the vibratory feed bowl 50 provides a means for conveying a plurality of the cores substantially simultaneously to a pickup station 320 (FIG. 3). This overcomes a major impediment to high speed present in the prior art, i.e., serial or singlefile core feeding and/or pickup. The bowl 50 has the usual ramps 311 that feed the cores by vibratory motion to a flat core pickup, feed, or transfer area that is adjacent the recess 314. The cores are vibrated, of course, at a rate not to exceed their fracturing or breaking point as they are quite fragile. Thus, referring to a particular core type handled by the present invention, i.e., a 0.008 inch inner diameter, 0.0l 3 inch outer diameter and 0.0225 inch thick core, the maximum feed rate in bowl 50 should not exceed one-half inch per second. it will be appreciated that, with this limitation, it is not practical to feed a group of such cores by a vibratory feeder in a single row or track at high rates of speed, as would be done in the prior art.
At the pickup station 320, in the exemplification, is an armate recess or cutout 314 in bowl 50 of feed bowl assembly 42. in the recess 319 is located a sector of the transfer wheel 84, as will be best seen in FIG. 3. in the exemplification, this sec tor is approximately 1 thereby including six vacuum pockets 232. Of course, as previously explained, the motor moves the transfer wheel in 18 steps, and while six vacuum pockets are always present at pickup station 320, a new, or empty, pocket 232 is presented to station 320 by each step. in this manner, the article transfer means, i.e., vacuum pickup pockets 232, are repeatedly capable of receiving and picking up cores from feed area 312 since each pocket 232 is present at station 320 for several (e.g., five in the exemplification) steps of wheel 84, This permits several rows of cores to be delivered simultaneously (and randomly) at one-half inch per second over the entire pickup area to satisfy the high speed feeding requirement of this invention.
In order to prevent the vacuum pickup pockets 232 from attracting and possibly picking up more than one core, means for preventing stacked cores from reaching the pockets is provided. This means is an arcuate gate 330 (FlGS. 3 and 4) mounted on bowl 50 adjacent recess 314. Gate 330 is mounted as indicated at 334, and spaced throughout a major portion of its length from feed area 312 to form a long arcuate slot 332 having a height greater than one core, but of course less than the height of two stacked cores. This prevents stacked cores from entering pockets 332, as shown in FIG. 4. in addition, as each pocket 232 is filled, the core therein itself acts as a pneumatic switch which stops the flow of vacuum, thereby rejecting any additional core that may be forceful to that same pocket 232 at the pickup station. Further, each core that is picked up acts as an antijamming means as it dislodges other cores or foreign matter that has lodged in slot 332.
CONTACT HEAD ASSEMBLY In the preferred embodiment of this invention, the operation on the miniature articles or cores 310 to be carried out during their transport is certain electrical tests that are effected by probes 280. It will be understood, however, that other tests might be conducted on cores 310, and that other miniature articles such as chips might be transported in wheel 84. In any event, it will be understood that the operation on the cores during their transport requires precise positioning or location thereof. The present invention provides this by holding the cores with at least a portion of their outside surface in contact with an inner wall or walls of its vacuum pickup pocket (see e.g. FIGS. 3-5). This precise position with respect to wheel 84 permits each probe to be extended through the core without misalignment and potential damage to the probe.
The contact head is mounted adjacent the periphery of transfer wheel 84 at a test station 340. The head 120, as shown in FIGS. 3 and 5 carries electrical contacts 344, 346, 348 and 350. The probe body 286 forms a path of conduction and completes a circuit between contacts 344 and 346, and the insert 288 does the same for contacts 348 and 350. Thus, with a probe 280 in the position shown in FIG. 5 preselected tests upon a core may be conducted.
OPERATlON Having described the major assemblies of the machine 20, the operation of the apparatus will now be explained. it will be seen in various figures of the drawings that a plurality of miniature articles, in this case annular magnetic cores 310, are fed by the feed bowl 50 in accordance with its usual manner of operation, i.e., by vibration, to the flat feed area 312 adjacent the pickup station 320. It is over this area 312 that the cores 310 are simultaneously available for pickup by the transfer means, i.e., vacuum pickup pockets 232 of the transfer wheel 84.
As previously mentioned, the motion of the motor shaft 182 is an incremental motion which, in the exemplification, takes approximately 7 milliseconds from start to stop. By virtue of the availability ofa plurality of the cores 310 at the pickup station 320 at all times, and the continuous presence of a sector of the transfer wheel 84 having a plurality of vacuum pockets (six in the present embodiment), the transfer or pickup of cores from feed bowl 50 to transfer wheel 84 is essentially on a parallel rather than on a serial basis. it will be appreciated that at any instant, there are a plurality of potential vacuum pockets for attracting cores at the pickup station 320. In this manner, it has been found that cores may be tested as fast as it is desirable to have the transfer wheel 84 rotate. It will be appreciated that the motion of the wheel 84 is a stepping motion since it is desirable to have the cores stationary during test, and not due to any limitation as to the pickup or transfer of cores from feed bowl 50 to pockets 232, which can and do pick up cores while wheel 84 is moving. Additionally, it will be understood that other means may be provided for rotating the wheel 84, e.g., a geneva mechanism.
As the transfer wheel 84 rotates, it initially picks up a core, 3100 for example, from the mass of plurality of cores present at flat area 312 of bowl 50. Core 310a is carried in its vacuum pocket 2320 in the direction indicated by arrow 342 from pickup station 320 to the test station 340 as wheel 84 rotates in steps. The test probe, designated 280a (FIG. 5) associated with pocket 232a is carried in barrel 82 with wheel 84 and gradually forced by cam 78 downwardly so that the probe 280a is driven or inserted axially through the center of the opening of the core 3100. The probe tip 281a is received within an insulated channel 291 in platform 194 and is located very exactly at the radial center of the core. With the probe in its most downwardly position, electrical contact is made between contacts 344 and 346 and between 348 and 350, and tests are carried out. in the exemplification, the motor and hence the probe barrel 82 and transfer wheel 84 are at rest during test.
When tests upon core 310a are complete, the results are used, in the preferred embodiment, as a basis for a sorting operation. Rotation of motor shaft 182 carries a tested core in 18 increments to a sorting station 390, where accept and reject tubes 182 and 96 are located. The cores are ejected from their pockets by a blow-off tube 382 (FIGS. 1 and 6) that is carried in a nonrotating sleeve 386 mounted within opening 184, around shaft 182 and mount 188. The blow-off tube 382 is open at its upper end for communication with blow-off passages 388 that are present in platform 194 and connect to each vacuum passage 240. This relationship may be readily observed in various of the figures, including FlGS. 2, 5 and 6. The sleeve 386 is mounted on springs 420 so that it floats" in opening 184 in order to provide a seal for the blow-off passages 388 over a major portion of their movement. The upper surface 387 of sleeve 386 thus ordinarily seals passages 388, thereby retaining the vacuum in passage 240. Only when a blow-off passage 388 communicates with blow-off tube 386 (FIG. 6) does the passage 388 become operative.
in order to eject a tested core 310 from its vacuum pocket 232, if the test has determined it to be an acceptable core, a positive pulse of air is applied to overcome the vacuum in vacuum passage 240 that is holding the core in its pickup pocket. This ejects the core into accept tube 102, but does not disturb the vacuum holding-other cores in their pockets 232 since the impedance of channel 220 is such that the positive pulse does not disturb the other cores in their respective pockets. A core thus tested and sorted as an acceptable core falls through the accept tube 102 into an accept vessel 90 mounted beneath the base 25 as shown in FIGS. 1 and 6.
In order to receive cores, the vessel 90 is removably mounted in an opening 402 in a mounting block 404 under the base 25 by a mounting clip 406 and is in direct communication with an accept port 408 in the mounting block 404. Port 408 is in turn in direct communication with the accept tube 102. The acceptable core 310C that was ejected from its vacuum pocket 232C in the transfer wheel 84 is thereby conveyed to the accept vessel 98. Since a positive pressure would be built up in the accept vessel 90 as more cores are transferred in this manner, it is necessary to relieve the pressure or otherwise the vessel 90 would resist the receipt of additional cores. Accordingly, a vacuum bleed passage 410 in mounting block 404 connects to a vacuum fitting 412. in this fashion, passage 410 is connected by suitable hoses (not shown) to the vacuum pump 262 or to some other vacuum source to draw a vacuum in vessel 90 and prevent its becoming pressurized. in the vacuum bleed passage 410 there is mounted a filter means 414 having a filter screen therein (not illustrated) that prevents the sorted cores in accept vessel 90 from being drawn into the bleed passage 410, while also screening out foreign particles and dust that may otherwise be conveyed into the vacuum system. When a core not ejected into accept tube 102 is carried to a point adjacent the eject tube 96 it will be removed or ejected from its vacuum pickup pocket since there is a positive source of air applied by the other blow-offtube 381 to the underside of the platform 194 and hence through the blow-off passages 388 reaching that position.
As mentioned, sleeve 386 forms a seal for passages 388 below each channel 220 in the platform 194, as otherwise the vacuum to pockets 232 would be ineffective. Sleeve 386 floats upon its mounting springs 420 so that it can follow any irregular movement or wobble of the core wheel 84 during its motion. in this manner, a continuous seal for the blow-off passages 388 is assured. However, since the sleeve 386 must be free to float within the opening 184 in base 25, it has a tendency to be rotated by the friction between its surface 387 and the bottom surface of the platform 194. This tendency to rotate is prevented by the location of the two blow-off tubes 382 and 381 in their slots 422 and 424 in the sleeve.
It is believed that the foregoing description of the apparatus for handling miniature articles such as magnetic cores shows the present invention to be truly novel and unique. The actual apparatus in practice has achieved a machine throughput of 100 cores per second or more. This, of course was previously not only unobtainable but actually unimaginable to those skilled in the art; i.e., those using conventional core handlers. Further, this apparatus is capable of handling either miniature cores or other miniature articles with extreme accuracy and at the speeds mentioned above.
Besides tremendous speed and ability to handle very small articles, the present apparatus and method have other heretofore unobtainable advantages. Thus, for example, it is quite easy to change the article type that is to be handled by the apparatus since the core handling assembly 44 is so accessible and easily dismantled. ln order to change core types for example, it is merely necessary to change pickup plate 196 so that its vacuum pockets will accommodate a different size or shape core.
While there is shown the preferred or exemplified embodiment of the apparatus, modifications that fall within the spirit and scope of the invention will become apparent to those skilled in the art. Thus, for example, while only the floating sleeve 386 is shown to be a plastic material (provided in order to reduce friction between the upper sealing surface 387 of the sleeve 386 and under surface of the platform 194), it will be apparent that other parts of the apparatus may be made of lighter material such as plastics in order to reduce the mass and to enable faster motor response. Further, while there is shown 20 pickup means or vacuum pockets in wheel 84, it is possible to have either greater or fewer pockets. For example, there has also been constructed a quality control model having only five pickup pockets disposed equally about the transfer wheel 84. Further, it is contemplated that a transfer wheel having 25 or more pickup means would be feasible, and, in such case while the stepping motor operation would have to be modified to provide smaller angles between the steps, this could easily be done, and would result in an even greater throughput or speed for the apparatus.
In conclusion, it will be understood that various other omissions and/or substitutions or changes in form and details of the device and in its operation may be made by those skilled in the art without departing from the true spirit of the invention. It is accordingly desired that the appended claims shall not be limited to any specific details thereof.
1. Apparatus for handling miniature articles, comprising:
a vibratory feeder having a bowl means for feeding a plurality of the miniature articles to a pickup station;
transfer means including a rotatable wheel for receiving the miniature articles by their outside surface in order to locate the miniature articles with respect to the transfer means, with said bowl means having a recess adapted to receive a sector ofsaid rotatable wheel;
the sector of said rotatable wheel received in said recess having a plurality of peripherally opening pocket means; and
means for moving said rotatable wheel to the pickup station with said rotatable wheel being repeatedly capable of receiving a miniature article from said bowl means while present at the pickup station.
2. Apparatus for handling miniature articles, comprising:
means for feeding a plurality of the miniature articles to a pickup station;
transfer means for receiving the miniature articles by their outside surface in order to locate the miniature articles with respect to the transfer means;
means for moving said transfer means to the pickup station with said transfer means being repeatedly capable of receiving a miniature article while present at the pickup station;
said transfer means including a rotatable wheel having a plurality of peripherally opening pocket means having inner walls;
means for retaining a single miniature article in each of said pocket means with at least a portion of its outside surface held tightly against one or more inner walls of the pocket means;
said feeding means including a vibratory feeder having a bowl, with said bowl having a recess adapted to receive a sector of said rotatable wheel;
the sector of said rotatable wheel received in said recess having a plurality of said peripherally opening pocket means; and
said moving means operating to rotate said rotatable wheel, with the plurality of the miniature articles being present to feed the pocket means as said wheel rotates.
3. The apparatus set forth in claim 2 wherein said rotatable wheel includes a generally centrally located vacuum means, and a plurality of passages connecting said vacuum means to said pocket means whereby said pocket means can attract and hold the miniature articles during rotation of said wheel.
4. Apparatus for conveying miniature articles in accurate position relative to a fixed reference plane, comprising:
a transfer wheel having a generally cylindrical outer surface defining the fixed reference plane;
said transfer wheel having a plurality of pickup means including openings in said outer surface;
means for rotating said transfer wheel;
means for feeding a plurality of the miniature articles to a pickup station where a sector of the outer surface of said transfer wheel is exposed, whereby a plurality of the miniature articles are transferable from said feeding means to a plurality of said pickup means;
a vacuum source in communication with said pickup means for attracting said miniature articles at said pickup station and holding them at least partially within said pickup means as said transfer wheel rotates, the miniature articles thereby being conveyed in accurate position relative to the outer surface of said transfer wheel; and
a feed slot at said pickup station, said feed slot being substantially wider than a single one of the miniature articles whereby a plurality of the miniature articles can be fed therethrough side-by-side, and the height of said feed slot being greater than the height of one and less than the height of two of the miniature articles whereby stacks of the miniature articles are prevented from reaching said transfer wheel.
5. Apparatus for conveying miniature articles in accurate position relative to a fixed reference plane, comprising:
a pickup station;
a transfer wheel having a generally cylindrical outer surface defining the fixed reference plane;
said transfer means having a plurality of pickup means including openings in said outer surface;
a sector of said transfer wheel including a plurality of said openings being located at said pickup station;
means for rotating said transfer wheel;
means for feeding a plurality of the miniature articles to said pickup station substantially simultaneously where said sector of the outer surface of said transfer wheel is exposed, whereby a plurality of the miniature articles are transferable from said feeding means to a plurality of said openings; and
a vacuum source in communication with said openings for attracting said miniature articles at said pickup station and holding them at least partially within said opening as said transfer wheel rotates, the miniature articles thereby being conveyed in accurate position relative to the outer surface of said transfer wheel.