US3450259A

US3450259A - Automatic classifying device

Info

Publication number: US3450259A
Application number: US604028A
Authority: US
Inventors: Albert Richard Waltz
Original assignee: Hughes Aircraft Co
Current assignee: Raytheon Co
Priority date: 1966-12-22
Filing date: 1966-12-22
Publication date: 1969-06-17
Anticipated expiration: 1986-06-17

Description

' June 17, 1969 Filed Dec. 22, 1966 A. R. WALTZ TOMATIC CLASSIFYING DEVICE fi l Awful. Azaazr 2 M4 72,

drralxasl June 17, 1969 A. R. wmz 3,450,259

AUTOMATIC CLAS S I FYING DEVICE Filed Dec. 22, 1966 Sheet 5 r 2 United States Patent 3,450,259 AUTOMATIC CLASSIFYING DEVICE Albert Richard Waltz, Fullerton, Calif., assignor to Hughes Aircraft Company, Culver City, Calif., a corporation of Delaware Filed Dec. 22, 1966, Ser. No. 604,028 Int. Cl. B07c 1/00, 9/00 U.S. Cl. 209-74- 19 Claims ABSTRACT OF THE DISCLOSURE This invention relates to an automatic classifying device and more particularly to a magnetic classifying device adapted to handle and sort a plurality of elements such as a semiconductor device having electrical conductor leads extending from opposite ends of a body member.

With the increased utilization of small elements and electrical components, a critical requirement has developed for the rapid and reliable handling and sorting of such components.

Therefore, it is an object of the present invention to provide an improved device for automatically handling and sorting a plurality of elements.

It is a further object of the present invention to provide an improved device for automatically handling and sorting a plurality of elements which utilizes a controllable magnetic force to direct the movement of the elements.

A still further object of the present invention is to provide an improved magnetic handling device which is combined with electronic test equipment to automatically test and sort semiconductor devices.

The above and other objects of this invention are accomplished in the generic embodiment of the present invention comprising a storage member for storing a plurality of electrical elements including dispensing means for dispensing said elements in a controllable frequency and along a predetermined path. A sampling system cooperates with said dispensing storage means for sampling at least one perdetermined physical parameter of each of said elements and for developing an electrical signal of a first magnitude when said parameter is of a first state and an electrical signal of a second magnitude when said parameter is of a second state. An electromagnetic member is in juxtaposition to said sampling system and is electrical-ly controlled thereby for developing a magnetic force of a magnitude and polarity sufiicient to cause said element to deviate from said predetermined path when the electrical signal developed by the sampling system is of said first magnitude.

Other objects, features and advantages of this invention will become apparent from reading the following detailed description of one embodiment of the present invention and referring to the accompanying drawings in which:

FIGURE 1 is a perspective view of a system for handling and sorting electrical components constructed in accordance with the principles of the present invention;

FIG. 2 is a schematic drawing of a portion of one of the test stations of FIG. 1 such as shown along line 2-2 in that figure illustrating the primary elements of the present invention; and

FIG. 3 is a side view of the element carrying belt or chain, permanent magnet and electromagnet of the present invention illustrating the relationship of these elements as shown in the embodiment of FIG. 1.

FIG. 4 is a second embodiment of the principles of the present invention shown in schematic form.

Referring now to FIG. 1, the principles of the present invention are embodied in a mhacine for automatically testing various parameters of a device or component '11 such as a semiconductor device having a portion of a material cap-able of sustaining a magnetic force such as a material having a permeance. In this embodiment, the devices 11 are dropped into a storage and dispensing mechanism 10 which may be a hopper or chute such as that described in U.S. Patent No. 2,975,878 and assigned to the instant assignee. .It is the function of the hopper and chute to separate and if desired to orient the devices so that as they reach the bottom of the chute they may be dispensed by an escapement mechanism such as that described in U.S. Patent No. 3,231,133, also assigned to the instant assignee. The storage and dispensing mechanism 10 allows the device 11 to fall onto a continuously moving element carrying belt or chain 12, typically of an electrical insulating material. The chain 12 is driven by a conventional motor drive system (not shown) and carries each of the devices into contact with at least one test station 14 located along its path. Each of the test stations 14 are electric'ally coupled to an electrical control unit 16 such as a conventional electronic tester which determines the nature of the electrical parameter to be sensed at each test station 14. By way of example of an electrical control unit 16 which would function with the present invention is the Automatic Diode and Rectifier Test Instrument D206 manufactured by Teradyne Inc., Boston, Mass. This instrument can be controlled to automatically test various parameters of electrical diodes and rectifiers.

The primary elements of novelty of the present invention are thought to reside in the elements functioning at each test station 14 to permit the device to pass the particular station if the desired parameter is sensed, or to remove the device from the chain 12 at that particular test station if an undesired parameter is sensed. Thus, giving each station 14 a go or no go condition on each device.

These novel elements are shown in detail in FIGS. 2 and 3. To complete the machine or system, such elements as storage bins and trays and structural members to support the various components are also shown in FIG. 1. In addition, a visual indication of the go or no go condition sensed at each station may be provided by an indicator such as a light 18 and/or counting device above each of the test stations 14 and electrically coupling it to the control unit 16 so that it is actuated by this unit simultaneously with the operation of the elements of the test station.

Referring now to FIGS. 2 and 3, at each test station 14 is at least one permanent magnet 20 and an electro magnet 22. The electromagnet 22 is positioned and magnetically oriented relative to the permanent magnet 20 so that when desired, the magnetic force developed by the electromagnet 22 can override that of the permanent magnet 20 to cause the device 11 to move in a predetermined direction such as into a storage-box 26 positioned below the track. Thus, by providing a pair of electrical contacts 28 adjacent to the magnetic field of the permanent magnet 20, and electrically coupling thereto the control unit through electrical conductor 29 and moving the device 11 so that they contact with the electrical contact 28, a parameter can be sensed and, an electrical signal pro- 3 vided to the electromagnet 22 by the control unit 16 to enable a magnetic force to be developed by the electromagnet 22 sufficient to override the force of the permanent magnet 20 and to pull the device from the chain 12 into the storage box 26. In this way the device 11 can be removed from the chain 12; however, if the electromagnet 22 does not develop a suflicient magnetic force, the permanent magnet 20 has a force sufficient to prevent the device from being separated from the chain 12 as it passes over the test station 14. Thus, at each station a go or no go condition can be sensed and the device or element can be caused to move correspondingly.

To accomplish this objective, the devices 11 are dispensed into a groove or notch of the continuous chain 12 at the storage mechanism 10 and are carried by the chain to each of the test stations 14. As the chain passes over the end sprockets 31 (FIG. '1) it is guided by an end guide 35 (FIG. 1) and a guide strip 36 which also act as a retainer to prevent the devices from dropping off the chain since the grooves are now facing down. The guide 36 contains a slot 38 at each work station 14 immediately adjacent to the contacts 28 and substantially beneath the permanent magnet 20. Since it is desirable to retain all of the devices 11 segregated at a particular work station, the box or container 26 is positioned beneath the slot 38. In this manner those devices 11 removed from the chain 12 by the force of the electromagnet will drop into the box or container 26.

In FIG. 4, rather than the continuous chain of FIG. 1, the storage elements are dispensed from the storage and dispensing mechanism 10 into engagement with a first electromagnet 40 which has associated with it a pair of contacts electrically coupled to the control unit (not shown), and a second and

third electromagnet

42, 44 positioned adjacent to the first magnet 40. The magnet 40 holds each device in contact with the pair of contacts so that a particular electrical parameter may be measured. After the parameter is measured the magnetic force of the first magnet 40 is removed and, depending upon the nature of the parameter sensed, the device '11 is acted upon by the second and

third magnet

42, 44 so that it will follow one of three paths, shown in dashed lines and identified as P1, P2, P3. Also shown in this embodiment are a plurality of baffles 50 and storage boxes 52 which would be used to properly guide and retain the devices 11. Thus, this embodiment has added to the first embodiment additional electromagnets which are controlled to develop the direction of movement of the device or element 11.

While the basic principles of this invention have been herein illustrated in two embodiments, it will be appreciated by those skilled in the art that variations in the disclosed arrangement both as to its details and as to the organization of such details may be made Without departing from the spirit and scope thereof. Accordingly, it is intended that the foregoing disclosure and the showings made in the drawings will be considered only as illustrative of the principles of the invention and not construed in a limiting sense.

What is claimed is:

-1. In an apparatus for sorting elements according to the state of at least one common predetermined electrical parameter thereof, each such element having a portion of a material having permeance, the combination of:

at least one test station having coupling means for electrically coupling such an element to parameter sensing control unit means for sensing the aforementioned common parameter of an element electrically coupled thereto and for generating an electrical signal of a first magnitude when such parameter is of a first state, and generating an electrical signal of a second magnitude when such parameter is of a second state; and

magnetic sorting means, associated with said test station, for developing a magnetic force of a magnitude and polarity sufficient to magnetically deflect the electrically coupled element by exerting a magnetic force upon the aforementioned portion in response to an electrical signal of the first magnitude from said parameter sensing control unit means.

2. The apparatus set forth in claim 1 wherein said coupling means includes a pair of electrical contact members positioned for simultaneous engagement with electrical terminals of the electrically coupled element.

3. The apparatus set forth in claim 2 wherein said contact members each have a portion adapted to allow such element to slide thereacross while moving in a predetermined path.

4. The apparatus set forth in claim 1 wherein said magnetic sorting means comprises an electromagnetic electrically coupled to said parameter sensing control unit means.

5. The apparatus set forth in claim 1 wherein said magnetic sorting means comprises a plurality of magnetic means for magnetically deflecting such elements in selected directions.

6. The apparatus set forth in claim 1 wherein said magnetic sorting means comprises a first magnetic means developing a first magnetic force coupled to the aforementioned portion to magnetically hold the electrically coupled element at or away from said test station and a second magnetic means for developing a second magnetic force for overcoming the first magnetic force when the parameter sensed is of the first state.

7. The apparatus set forth in claim 1 further including a storage and dispensing means positioned adjacent said test station for dispensing such elements onto said coupling means.

8. The apparatus set forth in claim 1 further including first means for causing such elements to move along a predetermined path and wherein said test station is positioned along the predetermined path, and wherein said magnetic sorting means is positioned so that those elements wherein the common parameter is of a first state are removed from the predetermined path upon deflection by said magnetic sorting means.

9. The apparatus set forth in claim 8 wherein said first means includes means for advancing such elements one at a time along the predetermined path.

10. The apparatus set forth in claim 8 wherein said first means is a continuously movable means.

11. The apparatus set forth in claim 8 wherein said first means includes a continuously movable conveyor means, and

means for guiding the movement of such elements along with said conveyor means.

12. The apparatus set forth in claim 8 wherein said first means includes a storage and dispensing means for feeding such elements toward said test station at a controllable frequency along the predetermined path.

13. The apparatus set forth in claim 8 wherein said first means includes a continuously movable means for moving suck elements along the predetermined path, and

a storage and dispensing means for placing such elements on said continuously movable means.

14. The apparatus set forth in claim 8 wherein said magnetic sorting means comprises first and second magnetic means;

said first magnetic means exerting a magnetic force upon the aforementioned portion to maintain such elements in the predetermined path; and

said second magnetic means exerting a magnetic force upon the aforementioned portion of a magnitude and polarity sufiicient to overcome the magnetic force of said first magnetic means when the parameter sensed is of the first state.

15. The apparatus set forth in claim 8 wherein said first means comprises a gravity feed means.

16. The apparatus set forth in claim 8 wherein said first means includes means for advancing such elements 5 continuously at a substantially constant speed along the predetermined path.

17. The apparatus set forth in claim 8 wherein said first means comprises a continuously movable means for advancing such elements along the predetermined path wherein said magnetic sorting means includes first magnetic means for maintaining such elements in contact with said continuously moving means, and

a second magnetic means positioned and oriented relative to said first magnetic means so as to develop a 10 magnetic force to overcome the magnetic force of said first magnetic means in response to an electrical signal of the first magnitude from said parameter sensing control unit means.

18. The apparatus set forth in claim 8 wherein said magnetic sorting means comprises a plurality of magnetic References Cited UNITED STATES PATENTS 7/1914 Hess 209-81 X 3/1966 Cole 209-81 X M. HENSON WOOD, IR., Primary Examiner.

R. A. SCHACHER, Assistant Examiner.

US. Cl. X.R. 209-75, 81