US20110241718A1

US20110241718A1 - Test Plate for Electronic Component Handler

Info

Publication number: US20110241718A1
Application number: US13/163,563
Authority: US
Inventors: Gerald F. Boe
Original assignee: Electro Scientific Industries Inc
Current assignee: Electro Scientific Industries Inc
Priority date: 2007-04-30
Filing date: 2011-06-17
Publication date: 2011-10-06
Also published as: TW200912339A; JP2014194424A; WO2008134405A1; KR20100016104A; US20080264826A1; JP2010526296A; US7965091B2; CN101680928A

Abstract

Test plates with improved test pockets are described herein. One embodiment is a circular test plate comprising a plurality of test pockets, each test pocket being a quadrilateral hole in the test plate, and each quadrilateral hole having four sides and four corners located at the intersections of the sides. Each of the four corners comprises at least one corner having a corner relief that extends from and intersects each of the at least one corner's two intersecting sides, and any remaining corners not having a corner relief. The test plate can be incorporated into a component handler.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No. 11/741,921, filed Apr. 30, 2007.

FIELD OF THE INVENTION

This invention relates to a test plate including pockets that increase the loading efficiency for an electronic component handler.

BACKGROUND

Electronic components are handled by a variety of different electronic component handlers. These different handlers include but are not limited to products sold by Electro Scientific Industries, Inc. of Portland, Oreg., the assignee of the present patent application. Electro Scientific Industries, Inc. sells a variety of electronic component handlers including but not limited to a high volume multi-layer ceramic chip (MLCC) capacitor tester sold as the Model 3300.
Commonly-assigned U.S. Pat. No. 5,842,579 entitled Electrical Circuit Component Handler describes an electronic component handler. With reference to FIG. 2 there is shown an overall pictorial view of the electronic component handler of U.S. Pat. No. 5,842,579, the entirety of which is incorporated herein by reference. FIG. 2 illustrates handler 10 including a loading frame 12 defining loading zone 13, a plurality of test modules 14 defining a test zone 15 and a blow-off module 16 defining a blow-off zone 17. In operation, electronic components pass through loading frame 12 and are individually drawn into test seats or pockets 22 formed as apertures and organized about a test plate. Typically, a stationary vacuum plate underlies the test plate and includes a plurality of vacuum channels used to create vacuum pressure in pockets 22. Different component types may require different pocket shapes and/or different pocket depths.
With continued reference to FIG. 2 it is seen that the test plate is positioned at an angle relative to vertical. By example, this angle may be a forty five degree angle. MLCC components pass through loading frame 12 and are directed by fences of the loading zone 13 toward test pockets 22. One component is received in one test pocket. In operation, the test plate indexes the loaded components toward testing modules 14 (in the direction of arrow B) where those components are tested. As the test plate continues to index, the components are presented to blow-off zone 17, where the components are removed from the handler 10 and organized based on test data from the test modules 14.
With reference to FIG. 2A there is shown a representative prior art electronic component 27 that includes electrode layers 27A. The size of component 27 is defined by a length 27B, a width 27C and a thickness 27D. The ratio between length 27B and width 27C define the aspect ratio of component 27.
Each test pocket 22 includes a loading area 26 as shown in FIG. 2B. In the example where the test plate is positioned at a 45 degree angle, gravity results in the loading area 26 comprising approximately 80% of the pocket width and the full pocket length. When the test plate is positioned at a 45 degree angle, a small part of the upper portion of the test pocket width is not substantially involved in loading but rather that small part merely operates to contain the component after loading.
With reference to FIG. 2C, one example of how a component is loaded into a test pocket 22 is shown. In particular, it is not uncommon for a component to pitch into pocket 22. A leading edge 28 of component 27 first enters pocket 22 and a trailing edge then falls into pocket 22 as illustrated by arrow 29.

BRIEF SUMMARY

A need has arisen to increase the loading efficiency of electronic components into test pockets on electronic component handlers. A test plate for use such a handler is provided where the test plate includes a plurality of test pockets wherein at least one of the test pockets includes at least one corner relief. In one embodiment the test pocket may include multiple corner reliefs that may be circular in their configuration.
Other applications of the present invention will become apparent to those skilled in the art when the following description is read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein:

FIG. 1 is a perspective view of an individual electronic component being loaded into a test seat/pocket according to an embodiment of the invention;

FIG. 2 is an overall pictorial view of a known electronic component handling machine;

FIG. 2A is a perspective view of an example electronic component;

FIG. 2B is a top plan view of an electronic component captured by a single test pocket;

FIG. 2C illustrates a perspective view of a prior art electronic component being loaded into a test pocket;

FIG. 3 is a plan view of an electronic component captured by a test pocket according to a first embodiment;

FIG. 4A is a plan view of a test pocket according to a second embodiment;

FIG. 4B is a plan view of a test pocket of a third embodiment;

FIG. 4C is a plan view of a test pocket of a fourth embodiment;

FIG. 4D is a plan view of a test pocket of a fifth embodiment;

FIG. 4E is a plan view of a test pocket of a sixth embodiment;

FIG. 4F is a plan view of a test pocket of a seventh embodiment; and

FIG. 5 is a perspective view of one test plate incorporating test pockets according to one embodiment of the invention.

DETAILED DESCRIPTION

A test plate for an electronic component handler is provided that includes test pockets. The test pockets are apertures in the test plate. Electronic components are delivered to an area near the test pockets and fall into or are pulled into the test pocket. At least one corner relief is provided for a test pocket to increase loading efficiency.
With reference to FIGS. 3-5, there is shown a pocket for use with a test plate in an electronic component handler. Electronic components such as MLCC's and those shown in FIG. 2A come in a variety of sizes, weights and aspect ratios. Certain types of components may be more difficult to load into a test pocket on a test plate. For example, components having an aspect ratio of 1:1 and of comparatively higher mass may have a lower loading efficiency.
With reference to FIGS. 1 and 3 there is shown a test pocket 30 including corner reliefs 32, 32A. Each corner relief 32, 32A represents an expanded area in a respective corner of test pocket 30. Corner reliefs 32, 32A may extend the full depth of test pocket 30. By creating corner reliefs 32, 32A, electronic component 27 can drop into pocket 30 with a reduced likelihood of being trapped, captured or otherwise obstructed. Sidewalls 33 and 34 of test pocket 30 may then capture component 27 so that component 27 can pass to a testing module 14 on machine 10. For example, with regard to a conventional 1210 chip, inclusion of corner reliefs 32, 32A of the type shown in FIGS. 1 and 3 have improved loading efficiency from approximately 85% to approximately 95%.
Corner reliefs may be positioned in a number of different fashions in order to improve the loading efficiency of components into a testing machine. These alternate embodiments are shown in FIGS. 4A-4F
FIG. 4A illustrates a test pocket 36 having corner pockets or reliefs 37 and 37A. Relief 37 extends in a direction lengthwise of the test pocket 36, while relief 37A projects in a direction widthwise of pocket 36. In FIG. 4B, test pocket 38 includes corner reliefs 39 and 39A extending in a direction offset from the length and width of pocket 38. FIG. 4C includes four corner reliefs 41, 41A, 41B and 41C in test pocket 40. The corner reliefs illustrated in FIG. 4C all extend at an angle offset from the width and length of pocket 40.
FIG. 4D illustrates test pocket 42 having four corner reliefs 43, 43A, 43B, 43C all extending in the length direction of pocket 42, while FIG. 4F shows a test pocket 46 where the reliefs 47, 47A, 47B, 47C all extend widthwise with respect to test pocket 46. FIG. 4E shows a test pocket 44 with two corner reliefs 45, 45A extending widthwise from test pocket 44.
Test pockets taught herein, including pockets 30 in the example of FIG. 5, can be organized in concentric rings 24 continuous about test plate 20. Test plate 20 is then mounted on the handler 10 for operation as described previously, replacing a conventional test plate with pockets as shown in FIGS. 2B and 2C. (In FIG. 5, only some of the pockets 30 are shown in detail due to size. The corner reliefs of these pockets 30 are exaggerated for clarity.)
Corner reliefs may be drilled out using known micro drilling techniques. While the corner reliefs have been illustrated as being semi-circular, the corner reliefs may be any number of different shapes including any polygon.
While the invention has been described in connection with certain embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is permitted under the law.

Claims

1. A circular test plate comprising:

a plurality of test pockets, each test pocket being a quadrilateral hole in the test plate, each quadrilateral hole having four sides and four corners located at the intersections of the sides, each of the four corners comprising:

at least one corner having a corner relief that extends from and intersects each of the at least one corner's two intersecting sides, and

any remaining corners not having a corner relief.

2. The test plate of claim 1, wherein the test plate is installed in an electronic component handler at an inclined angle.

3. The test plate of claim 2 wherein each test plate has a loading efficiency, whereby the loading efficiency of the test plate having test pockets with corner reliefs is greater than a test plate having test pockets without corner reliefs, due to the addition of the corner reliefs.

4. The test plate of claim 1 wherein at least one corner relief comprises an arcuate hole extending from a top surface of the test plate to a bottom surface of the test plate beyond the intersecting sides of the corner relief's corner.

5. The test plate of claim 1 wherein:

the test plate has a thickness, a top surface and a bottom surface;

each of the test pockets includes side walls that are contiguous and flat between the top surface and the bottom surface of the test plate and the corners of its test pocket; and

each side wall is perpendicular to at least one of the top surface or the bottom surface of the test plate.

6. The test plate of claim 5 wherein each corner relief includes at least one side wall, the at least one side wall being contiguous between the top surface of the test plate, the bottom surface of the test plate, and the intersections between the corner relief and the intersecting sides of the corner relief's corner.

7. The test plate of claim 1 wherein the at least one test pocket includes two corners having a corner relief and two corners not having a corner relief.

8. The test plate of claim 7 wherein the test plate is installed in an electronic component handler about an axis of rotation and wherein the two corner reliefs are situated at radially-outer corners of a test pocket.

9. The test plate of claim 1 wherein the plurality of test pockets are arranged in a plurality of concentric rings on the surface of the test plate.

10. A test plate including a plurality of test pockets wherein:

the test plate is circular, has a thickness, a top surface and a bottom surface;

each of the plurality of test pockets is a quadrilateral hole through the test plate having a radially-inner surface, a radially-outer surface and two side surfaces;

the surfaces of each test pocket are perpendicular to at least one of the top surface or the bottom surface of the test plate;

the surfaces of each test pocket meet to form four interior edges at corners of the test pocket;

the surfaces of each test pocket are each contiguous between the top surface and the bottom surface of the test plate; and

each test pocket includes at least one corner relief at an interior edge thereof, each corner relief extending the test pocket beyond at least one of the surfaces of the test pocket.

11. The test plate of claim 10 wherein the at least one corner relief comprises an arcuate hole extending from one of the side surfaces and one of the radially-inner or the radially-outer surface.

12. The test plate of claim 10 wherein:

the surfaces of each test pocket extends between one of two of the interior edges, one of the interior edges and a corner relief, or two corner reliefs; and

each test pocket is contiguous between those extents.

13. The test plate of claim 10 wherein:

the test pocket includes two corner reliefs adjacent a respective one of the interior edges; and

the test pocket includes rounded corners at the remaining interior edges.

14. The test plate of claim 13 wherein:

the test plate is rotatably mounted in a electronic component handler; and

the each of the two corner reliefs is situated about the interior edge at the intersection between the radially-outer surface and a respective one of the two side surfaces.

15. In a method of testing electronic components using a rotatable test plate installed in an electronic component handler at an inclined angle and having a plurality of test pockets extending through the rotatable test plate, the improvement comprising:

rotating the test plate so that each of a plurality of electronic components resting on a top surface of the rotatable test plate is guided into a respective test pocket of the plurality of test pockets by a corner relief, each test pocket being a quadrilateral hole in the rotatable test plate, each quadrilateral hole having four sides and four corners located at the intersections of the sides, at least one corner of the four corners having the corner relief that extends from and intersects each of the at least one corner's two intersecting sides, and any remaining corners of the four corners not having a corner relief

16. The method of testing electronic components of claim 15, further comprising:

arranging the corner relief so that a loading efficiency of the electronic component handler is greater than a loading efficiency of the electronic component handler without the corner relief.

17. The method of claim 15 wherein the corner relief comprises at least two corner reliefs, one corner relief situated at a first radially-outer corner of the test pocket and another corner relief situated at a second radially-outer corner of the test pocket.