US20070020066A1

US20070020066A1 - Centering and orientation apparatus

Info

Publication number: US20070020066A1
Application number: US11/485,089
Authority: US
Inventors: Thomas Seow Woo; Ching Tan
Original assignee: LKT Automation Sdn Bhd
Current assignee: LKT Automation Sdn Bhd
Priority date: 2005-07-12
Filing date: 2006-07-12
Publication date: 2007-01-25
Also published as: CN100435313C; CN1933120A

Abstract

An apparatus for centering and orienting article comprising a centering body having a bore extending therethrough, a plurality of support members extending from the upper end of the centering body, an arm pivotally attached between two adjacent support members, a rod received in the bore having slidable and rotatable movement; a centering base attached on top of the rod which include the article holding space at the center and a plurality of slots extending from the periphery towards the center of the centering base. A centering finger is slidably attached to each slots of the base. When the rod is extended upwards it engages with the arm which in effect moves the centering finger away from the center of article placement area; and when rod is lowered and disengages with the arm to revert back to the original position and orientation means provided to rotate the article.

Description

FIELD OF INVENTION

The present invention relates to an apparatus for centering and orienting article such as integrated circuits or the likes.

BACKGROUND OF THE INVENTION

In the semiconductor manufacturing industry for producing Integrated Circuits, there are many processes involved in doing so and one of the process which is important is the testing of parts before packaging (packing IC or to complete IC).
For this typically a dedicated apparatus is used. Because the tolerance involved in placement of a chip into a tester is very small, positioning and placement accuracy is important. The tester is typically integrated with a material-handling machine. The material-handling machine handles the unloading of work units from input unit trays and the transferring of units through pick-and-place heads to the final packaging medium, with the testing process in between.
To achieve placement and positioning accuracy in the testing cavity, typically a jig is used to reposition the work unit at the pickup head before placement into the testing cavity. This significantly reduces the probability of unit misalignment in the testing cavity. However, passive centering of units in this manner is less reliable thus the need for a more efficient alternative.
In addition, certain processes integrated with the material-handling machine, such as vision inspection processes or more prominently the testing processes, typically require the unit to be orientated in a certain direction. Because not all units in the input unit tray may be orientated in the desired direction, material-handling machines incorporate a separate module for the reorientation process as well. This additional module adds to the material cost of the machine.
A typical apparatus according to prior art is shown in FIG. 10 where the rotating and centering apparatus is of two separate apparatus. The present invitation is an effective integration between these two apparatus.
The present invention incorporates both the centering and the reorientation processes into one compact module and have filed another application for this. The invention reduces material cost and provides for better utilisation of space in the material-handling machine. For flexibility of application, the invention also incorporates a support structure that enables adjustments in the z-axis. The modularity of the invention enables cross-machine application without the need for redesign.
However, the first embodiment of the present invention has one disadvantage. When a chip is not accurately placed at the receiving part of the invention, during the process of centering and orientating the chip, there is a possibility of damaging the chip. Therefore a second embodiment of the present invention is aimed at overcoming the problem faced by the first embodiment of the invention.

SUMMARY OF THE INVENTION

A first embodiment of the apparatus for centering and orienting articles such as integrated circuits or the like comprising a centering body having a plurality of support members at the upper end of said centering body with a bore extending therethrough and a hollowed shaft coaxial with said bore where said hollowed shaft is telescopically connected to a rod providing slidable and rotatable movement to said rod, a finger pedestal attached to an upper end of said rod and placed within said centering body; an arm pivotally attached between each two adjacent support members, a centering base mounted at the top of said support members, said centering base includes an article holding space at the center and a plurality of slots extending from the periphery towards the center of said centering base, an orientation means attached to said rod to rotate said article holding space, and a centering finger slidably attached to said each slots of the centering base, wherein when said rod is extended upwards it engages and pivots said arm which in effect moves said centering finger away from the center of said article holding space and when said rod is lowered downwards it disengages and pivots said arm revert back to the original position moving said article into place accordingly.
A second embodiment of the apparatus for centering and orienting articles such as integrated circuits or the like comprising a centering body having a plurality of support members at the upper end of said centering body with a bore extending therethrough and a hollowed shaft coaxial with said bore where said hollowed shaft is telescopically connected to a rod providing slidable and rotatable movement to said rod, a finger pedestal having a pedestal attachment attached to an upper end of said rod and placed within said centering body, an arm pivotally attached between each two adjacent support members, a centering base mounted at the top of said support members, said centering base includes an article holding space at the center and a plurality of slots extending from the periphery towards the center of said centering base, an orientation means attached to said rod to rotate said article holding space; and a centering finger slidably attached to said each slots of the centering base, wherein when said rod is extended upwards it engages and pivots a first pair of arms which is mounted in between said pedestal attachment and said finger pedestal which in effect moves a first pair of centering fingers away from the center of said article holding space and when said rod is lowered downwards it disengages and pivots a second pair of arms to revert back to the original position moving said article into place accordingly.

BRIEF DESCRIPTION OF THE DRAWINGS

Descriptions of the functional and physical aspects of the invention in the proceeding text will become more apparent with reference to the following drawings.
FIG. 1 is an isometric view assembly drawing of the centering module of the present invention.
FIG. 2 is an exploded assembly view of the mechanism involved in the centering process of the present invention.
FIG. 3 is a cross sectional view of the partial assembly shown in FIG. 2.
FIG. 4 is a cross sectional view showing the retraction of centering fingers.
FIG. 5 is a cross sectional view showing the extension of centering fingers.
FIG. 6 is an illustration of the orientating mechanism.
FIG. 7 is an exploded view of the centering and orienting apparatus of the second embodiment of the present invention.
FIG. 8 shows a cross sectional view of the centering and orienting apparatus of FIG. 7 with the centering finger moved in outward radial direction.
FIG. 9 shows a cross sectional view of the centering and orienting apparatus of FIG. 7 with the centering finger moved in inward radial direction.
FIG. 10 is front perspective view of the prior art of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a centering and orientating module of the present invention. The top section of the support structure consisting of a mounting plate and support bar connected through a pair of polygonal plates which is adjustable relative to the bottom support plate. A pair of screws inserted through threaded holes in the support bar rests on the upward facing surface of the bottom support plate's lateral walls. A motor (63) and a bearing housing are attached to the support structure.
FIG. 2 shows a partial assembly of the centering mechanism of the present invention. As a cylinder (17) extends, it exerts an upward force on a clamping screw (not shown) that is connected to a rod (20). This rod (20) passes through two slide bushes (21) which is contained within a hollowed shaft (18) of a centering body (22). The centering body (22) includes a finger like support members (12) at the upper end of the centering body (22) and a bore extending therethrough. The hollowed shaft (18) is attached at the bottom end of the centering body (22). The slide bushes (21) reduce dynamic friction to provide for a smooth transition of the rod (20). The upper end of the rod (20) is fastened to a finger pedestal (23). Preferably four arms (24) are each pivoted at the elbow between a pair support members (12) of the centering body (22). A first end (24 a) of each arm (24) is inserted within a cavity (26) of the finger pedestal (23). A second end (24 b) of each arm (24) is mated with a U-shaped section of a finger holder (27). These holders (27) are inserted into a plurality of slots (28) provided on a centering base (29), which is mounted to the centering body (22). A finger (30) is attached to the finger holder (27) to provide the required surface for clamping and gripping.
The cross sectional view of the centering mechanism is shown in FIG. 3. A compression spring (31) is located within the centering body (22). When the cylinder (17) extends and actuates the rod (20), the compression spring (31) is compressed. When the force exerted by the cylinder (17) is removed, the compression spring (31) expands pushing the rod (20) back down to its initial position.
FIG. 4 is an illustration of an instant when the fingers (30) are retracted. As the finger pedestal (23) moves upwards due to the upward movement of the rod (20), the inner surface of a lower flange (40) of the finger pedestal (23) pushes against the section of the first end (24 a) of the pivoted arm (24) within the cavity (26) of the finger pedestal (23). As the arm (24) is pivoted, the upward force applied causes the arm (24) to rotate centered at the pivot point (42). This in turn causes the second end (24 b) of the arm (24) mated with the finger holder (27) to exert a force on an outer wall (43) of the U-shaped section of the finger holder (27), which results in the outward radial movement of the finger (30).
The illustration of an instant when the fingers are extended is shown in FIG. 5. As the finger pedestal (23) moves downwards due to the downward movement of the rod (20), the inner surface of an upper flange (50) of the finger pedestal (23) pushes against the section of the first end (24 a) of the arm (24) within the cavity (26) of the finger pedestal (23). As the arm (24) is pivoted, the force applied causes the arm (24) to rotate centered at the pivot point (42). This is turn causes the second end (24 b) of the arm (24) mated with the finger holder (27) to exert a force on an inner wall (51) of the U-shaped section of the finger holder (27), which results in the inward radial movement of the finger (30).
FIG. 6 is an illustration of the orientating mechanism. The mid portion of the centering body (22) is coupled to a pulley (60) that is connected with a belt (61) to another pulley (62) that is driven by the motor (63). The rotating motion on the pulleys (61, 62) will cause the centering body (22) to rotate together with other corresponding components within the centering mechanism except for the rod (20), (not shown in FIG. 6 but evident in preceding illustrations) and the finger pedestal (23), (not shown in FIG. 6 but evident in preceding illustrations) that is independent of any rotational motion of the centering body (22) as both is are not fastened to the centering body (22) and are positioned at the rotational axis of the centering body (22). The cavity (26) of the finger pedestal (23) allows the arms (24) to rotate along the cavity (26) during rotation. The bearing housing (64) with bearing (not shown) is also coupled to the centering body (22).
In a second embodiment of the present invention, the construction for all the parts of the centering and orientating mechanism is similar to the first embodiment except for the construction of the finger pedestal (23). The centering mechanism of the second embodiment is also includes a centering body (22) having a plurality of support members (12) at the upper end and a hollowed shaft (18) at the lower end of the centering body (22) where a rod (20) passes therethrough. The finger pedestal (23) of the second embodiment is formed with its upper flange (50) having a transverse slot (44) for receiving a pedestal attachment (41) as shown in FIG. 7. The pedestal attachment (41) has a top plate (42) and a shaft (43) to be fitted into the finger pedestal (23) is attached in perpendicular position at the middle of the top plate (42). The pedestal attachment (41) can be lifted up from the finger pedestal (23) to a predetermined level.
The upper end of the rod (20) is fastened to the shaft (43) of the pedestal attachment (41). Preferably four arms (60) are each pivoted at the elbow between a pair of support members (12) of the centering body (22). A first end (24 a) of each arm (60) is inserted within a cavity (26) of the finger pedestal (23). A second end (24 b) of each arm (60) is mated with a U-shaped section of a finger holder (27). A centering finger (30) is attached to the finger holder (27) to provide the required surface for clamping and gripping.
In this embodiment, the second end (24 b) of a first pair of opposing arms (60 a) is engaged with an inner surface of the top plate (42) of the pedestal attachment (41). As the pedestal attachment (41) moves upwards due to the upward movement of the rod (20), the inner surface of the top plate (42) is lifted up leaving a gap for the opposing arms (60 a) to be pivoted at its elbow within the cavity (26) of the finger pedestal (23). As the opposing arms (60 a) are pivoted, the outward force of the second arm (24 b) will cause the opposing finger holders (27 a) which are attached with the second arm (24 b) moved in the outward radial movements from the centering base (29) as shown in FIG. 8.
As the rod (20) moves further upwards, the finger pedestal (23) will be pushed in upward movements till the inner surface of a lower flange (40) of the finger pedestal (23) pushes against the section of the first end (24 a) of the other pair of opposing arms (60 b) within the cavity (26) of the finger pedestal (23). The other opposing finger holders (27 b) will then moved in outward radial movements from the centering base (29).
As the rod (20) moves downwards, the pedestal attachment (41) will be pulled downwardly with the inner surface (41) of the top plate (42) pushes against the section of the first end (24 a) of the first pair of opposing arms (60 a) within the cavity (26) of the finger pedestal (23). As the first pair of opposing arms (60 a) is pivoted, the force applied causes the arm (60 a) to rotate centered at the pivot point (42). This will cause the opposing finger holders (27 a) which are attached with the second arm (24 b) moved in the inward radial movements to the centering base (29) as shown in FIG. 9.
As the rod (20) moves further downwards, the finger pedestal (23) will be pulled in downward movements till the inner surface of the lower flange (40) of the finger pedestal (23) pushes against the section of the first end (24 a) of the second pair of opposing arms (60 b) within the cavity (26) of the finger pedestal (23). The other pair of opposing finger holders (27 b) will then moved in inward radial movements to the centering base (29).
With these arrangements, the first opposing finger holders (61 a) will be first moved in outward radial movements when the rod (20) is moved upwardly, and inward radial movements when the rod (20) is moved downwardly. Further upward movements of the rod (20), will then move the second opposing finger holders (61 b) in outward radial movements and also further downward movements of the rod (20), will then move the second opposing finger holders (61 b) in inward radial movements. This will prevents the possibility of damaging the chip, when the chip is not accurately placed at the receiving part of the invention, during the process of centering and orientating the chip.
While the preferred embodiments of the present invention and their advantages have been disclosed in the above detailed description, the invention is not limited thereto but only by the spirit and scope of the appended claims.

Claims

1. An apparatus for centering and orienting articles such as integrated circuits or the like comprising;

a centering body having a plurality of support members at the upper end of said centering body with a bore extending therethrough and a hollowed shaft coaxial with said bore where said hollowed shaft is telescopically connected to a rod providing slidable and rotatable movement to said rod;

a finger pedestal attached to an upper end of said rod and placed within said centering body;

an arm pivotally attached between each two adjacent support members;

a centering base mounted at the top of said support members, said centering base includes an article holding space at the center and a plurality of slots extending from the periphery towards the center of said centering base;

an orientation means attached to said rod to rotate said article holding space; and

a centering finger slidably attached to said each slots of the centering base, wherein when said rod is extended upwards it engages and pivots said arm which in effect moves said centering finger away from the center of said article holding space and when said rod is lowered downwards it disengages and pivots said arm revert back to the original position moving said article into place accordingly.

2. The apparatus for centering and orienting articles as claimed in claim 1, wherein said finger pedestal includes an upper flange and a lower flange, with a cavity formed therebetween.

3. The apparatus for centering and orienting articles as claimed in claim 1, wherein said centering finger is slidably attached to said each slots of the centering base by a finger holder.

4. The apparatus for centering and orienting articles as claimed in claim 3, wherein said finger holder includes a longitudinal aperture on the top surface for receiving said centering finger and a U-shaped section formed by an outer wall vertically fixed at the edge and an inner wall vertically fixed at substantially middle of the bottom surface of said finger holder.

5. The apparatus for centering and orienting articles as claimed in claim 1, wherein said arm includes a first end which is inserted within said cavity of the finger pedestal and a second end which is mated with said U-shaped section of said finger holder.

6. The apparatus for centering and orienting articles as claimed in claim 1, wherein said apparatus has four arms pivotally attached between each two adjacent support members.

7. The apparatus for centering and orienting articles as claimed in claim 1, wherein said orientation means includes a pulley coupled to said centering body, said pulley connected with a belt to another pulley that is driven by a motor to translate the rotational movement of said motor to rotate said centering body.

8. The apparatus for centering and orienting articles as claimed in claim 7, wherein said centering body is mounted with a compression spring within said hollowed shaft of the centering body.

9. The apparatus for centering and orienting articles as claimed in claim 8, wherein said centering body is further attached with a cylinder for extending and actuating said rod.

10. An apparatus for centering and orienting articles such as integrated circuits or the like comprising;

a finger pedestal having a pedestal attachment attached to an upper end of said rod and placed within said centering body;

an arm pivotally attached between each two adjacent support members;

a centering finger slidably attached to said each slots of the centering base, wherein when said rod is extended upwards it engages and pivots a first pair of arms which is mounted in between said pedestal attachment and said finger pedestal which in effect moves a first pair of centering fingers away from the center of said article holding space and when said rod is lowered downwards it disengages and pivots a second pair of arms to revert back to the original position moving said article into place accordingly.

11. The apparatus for centering and orienting articles as claimed in claim 10, wherein said finger pedestal is formed with an upper flange having a transverse slot for receiving said pedestal attachment.

12. The apparatus for centering and orienting articles as claimed in claim 10, wherein said pedestal attachment has a top plate and a shaft to be fitted into said finger pedestal, whereby said pedestal attachment can be lifted up from said finger pedestal to a predetermined level.

13. The apparatus for centering and orienting articles as claimed in claim 10, wherein said apparatus includes a second pair of arms with each arm having a first end inserted within a cavity of said finger pedestal and a second end mated with a U-shaped section of a finger holder.

14. The apparatus for centering and orienting articles as claimed in claim 13, wherein said second pair of arms is arranged to move in upward movements when said rod is moved further upwards and thus moves a second pair of centering fingers away from the center of said article holding space and to move in downward movements when said rod is moved further downwards and thus said second pair of centering fingers to revert back to the center of said article holding space.