U.S. patent number RE35,027 [Application Number 08/131,561] was granted by the patent office on 1995-08-29 for pick and place method and apparatus.
This patent grant is currently assigned to Delaware Capital Formation, Inc.. Invention is credited to Phillip A. Ragard.
United States Patent |
RE35,027 |
Ragard |
August 29, 1995 |
Pick and place method and apparatus
Abstract
A turret assembly is movable in X and Y and a turret of the
assembly is rotatable to position a selected one of a plurality of
spindles at a transfer station of the turret. The selected spindle
is telescopic to pick a component from a supply point and to place
the component at a placement point on a circuit board or the like.
An assembly for squaring, centering, orienting, and/or testing a
component being held by another spindle of the turret is actuated
generally concurrently with extending of the selected spindle.
Alternatively, the spindle at the transfer station may be retained
in the retracted position during actuation of the squaring
assembly. Much time is saved by loading components on the plurality
of the spindles of the turret at one or more supply stations and
then placing all of these components without the need for
transferring back and forth between the supply and P.C. board.
Inventors: |
Ragard; Phillip A. (Binghamton,
NY) |
Assignee: |
Delaware Capital Formation,
Inc. (Wilmington, DE)
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Family
ID: |
27400048 |
Appl.
No.: |
08/131,561 |
Filed: |
October 4, 1993 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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888314 |
May 27, 1992 |
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773154 |
Oct 8, 1991 |
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Reissue of: |
247512 |
Sep 22, 1988 |
04872258 |
Oct 10, 1989 |
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Current U.S.
Class: |
29/740; 83/411.7;
29/33J; 198/476.1; 29/743; 29/742; 198/802 |
Current CPC
Class: |
H01L
21/6838 (20130101); H05K 13/0413 (20130101); H05K
13/0409 (20180801); H05K 13/041 (20180801); Y10T
83/6561 (20150401); Y10T 29/519 (20150115); Y10T
29/53178 (20150115); Y10T 29/53191 (20150115); Y10T
29/53187 (20150115) |
Current International
Class: |
H01L
21/67 (20060101); H01L 21/683 (20060101); H05K
13/04 (20060101); H05K 003/30 () |
Field of
Search: |
;29/739,740,741,742,743,563,785,792,335 ;83/411.7,552
;198/477.1,476.1,802 ;221/233,234 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
"Multigripper Robot Slashes Insertion Time 75 Percent", Electronic
Packaging and Production, Jun. 1988, p. 12. .
"Sutromat SMD 201", advertising brochure of Sutron Electronic GmbH,
undated. .
"STM-77 Turret Method Suction Head", advertising brochure of Nitto
Kogyo Co., Ltd, undated..
|
Primary Examiner: Gorski; Joseph M.
Attorney, Agent or Firm: Banner & Allegretti, Ltd.
Parent Case Text
This application is a continuation of U.S. application Ser. No.
07/888,314, filed on May 27, 1992 and now abandoned, which is a
continuation of U.S. application Ser. No. 07/773,154 filed on Oct.
8, 1991 and now abandoned, which is a Reissue of U.S. Pat. No.
4,872,258.
Claims
Now that the invention has been described, I claim:
1. In an apparatus for selectively performing the operations of
picking components from one point and placing them at another point
by means of a turret assembly having a rotatable turret with plural
component holding spindles protruding therefrom and angularly
spaced about a hub thereof, said picking and placing operations
being performed by transferring components respectively to and from
said spindles at a component transfer station of said turret
assembly wherein said component transfer station is situated at a
particular circumferential angular location about the hub of said
turret, the improvement comprising:
displacer means for extending and retracting at least one of said
spindles relative to said hub in order to perform said
transferring;
said displacer means comprising a pin protruding laterally from
said at least one spindle and into an annular groove of a guide
ring generally centered on said hub, such that said pin rides in
said groove during rotation of said turret to retain said spindle
in a retracted condition;
said displacer means further comprising a section of said guide
ring which is displaceable generally radially of said hub relative
to the remainder of said guiding, said section comprising an
arcuate portion of said annular groove; means for moving said
section, so that when pin extends into the annular groove of said
section, radial displacement of said section results in radial
displacement of said spindle into an extended condition.
2. The improvement as in claim 1 and further comprising:
means for relocating said turret assembly and presenting said
component transfer station of said turret at a selected one of said
points for transferring said component in a direction generally
normal to a plane containing said point.
3. The improvement as in claim 1, and further comprising:
means for rotating turret prior to relocating said turret
assembly.
4. The improvement as in claim 1, and further comprising:
means for rotating turret during relocating said turret
assembly.
5. The improvement as in claim 1, and further comprising:
means for rotating said turret after relocating said turret
assembly.
6. The improvement as in claim 1, and further comprising:
means for retracting said spindle partially during said picking and
placing according to pressures experienced by said component during
said operations.
7. The improvement as in claim 6, and further comprising:
means for limiting said partial retracting in order to limit said
pressure experienced by said component.
8. The improvement as in claim 7, and further comprising:
means for adjusting said limiting.
9. The improvement as in claim 1, and further comprising:
a squaring assembly and means for actuating said squaring assembly
and thus squaring another component being held by another spindle
which is not at said component transfer station.
10. The improvement as in claim 9, and further comprising:
means for actuating said squaring assembly generally simultaneously
with said spindle extending and retracting.
11. The improvement as in claim 9, and further comprising:
means for preventing said spindle extending and retracting during
actuating of said squaring assembly.
12. The improvement as in claim 9, and further comprising:
means for centering said other component upon actuating said
squaring assembly.
13. The improvement as in claim 9, and further comprising:
means for testing electrical functioning of said other component
upon actuating said squaring assembly.
14. The improvement as in claim 9, and further comprising:
means for orienting said other component upon actuating said
squaring assembly. .Iadd.
15. An apparatus for equipping printed circuit boards with
electronic components, said apparatus comprising:
at least two supply stations;
a rotatable turret having a plurality of pick-up spindles for
components, each said spindle having a vacuum nozzle suitable for
picking components from any of said supply stations;
at least one processing station contiguous with said rotatable
turret; and
means for displacing and positioning said turret together with said
at least one processing station in X and Y directions, said means
including programmable controller means for controlling the
movement of said turret in said X and Y directions and permitting a
plurality of components to be picked up from different supply
stations by the plurality of vacuum nozzles so that the components
picked up by said spindles from said supply stations can be passed
by said processing station during indexing and translation of said
turret and so that any of said plurality of components loaded on
said plurality of spindles from any of said supply stations then
may be placed on the circuit board at any programmable position.
.Iaddend. .Iadd.
16. An apparatus as in claim 15, wherein said processing station is
a squaring and centering assembly. .Iaddend. .Iadd.17. An apparatus
as in claim 15, wherein said processing station is a component
tester. .Iaddend.
Description
PRIOR ART CROSS REFERENCES
U.S. Pat. No. 4,458,412--Dean, et al., "LEADLESS CHIP PLACEMENT
MACHINE FOR PRINTED CIRCUIT BOARDS":, issued Jul. 10, 1984.
U.S. Pat. No. 4,611,397--Janisewicz, et al., "PICK AND PLACE METHOD
AND APPARATUS FOR HANDLING ELECTRICAL COMPONENTS", issued Sep. 16,
1986.
U.S. Pat. No. 4,721,907--Dean, et al., "APPARATUS FOR AUTOMATED
TESTING OF SURFACE MOUNTED COMPONENTS", issued Jan. 26, 1988.
BACKGROUND OF THE INVENTION
The present invention relates to apparatus for the precision
placement of electronic components on a hybrid circuit substrate
and, more particularly, to the placement of small articles such as
semiconductor chips, capacitor chips and integrated circuit chips
on a ceramic substrate which has been preprinted with a thick film
conductor pattern.
As the name suggests, hybrid circuits are a combination of discrete
and integrated circuit techniques. As in integrated circuits,
conductors, resistors and conductive lands are printed on a ceramic
substrate. In thick film technology, the printed elements are
generally several mils thick. Then discrete chips are precisely
positioned over the conductive lands and subsequently bonded in
position in a manner to complete the electrical circuit. The
printed conductor lands provide a pattern which precisely matches
to the corresponding conductive portions of the chips that connect
to the circuit elements within the chip as by solder. The bonded
chips and substrate, with an exposed lead frame, are frequently
encapsulated in toto in a potting compound for protection against
physical and environmental damage. Use of unencapsulated chips on
the circuit board allows for the manufacture of physically smaller
circuits than those where discrete components which have already
been encapsulated have their leads inserted into circuit boards
fired with receiving connectors or into predrilled holes wherein
the leads are subsequently cut and clinched. A primary advantage of
chips is their small size, some being nearly microscopic. Chips in
the order of 0.030 by 0.030 inches square and 0.010 thick and
solder connection portions and conductor lands in the order of
0.005 inches in height and width, and spaced apart by similar
distances, are not uncommon. Nevertheless, for the hybrid circuit
technique to be successful, the small chips must be positioned and
oriented such that when placed on the substrate, all solder
connection portions and lands are properly connected without error.
This requires a high degree of precision in positioning which was
achieved in early development of these techniques by human
operators using microscopes and tweezers.
The need for automatic, rapid, precise, repeatable and low cost
means to position and bond chips on substrates was apparent if the
burgeoning requirements of mass production in the electronics
industry were to be met. Generally speaking, in the apparatuses
which have been developed in the past, the chip or other small
component, e.g., beam leaded components, are picked up by a hollow
probe device which is connected to a vacuum source. When the probe
touches the upper flat surface of the chip, the vacuum within the
probe holds the chip against the probe end. The chip is then
raised, translated in X and Y to the appropriate location above
substrate, and lowered in Z onto the substrate. Prior attempts have
been made to improve the precision of placement of the components
onto the circuit board by combining centering fingers with the
vacuum probe. Thus, while the probe supports the component by
vacuum, the fingers center the component relative thereto prior to
placement. Permanent bonding of chip to substrate is accomplished
in some systems while the probe continues to hold the chip. In
other systems, the conductive lands are pretreated with some form
of tacky adhesive or soldering flux. The probe gently presses the
chip surface into the tacky adhesive so that electrical contact is
made with the conductive lands. Then the vacuum within the probe is
released and the chip remains adhered to the substrate as the probe
is withdrawn. A positive gas pressure within the probe is sometimes
used to separate the chip from the probe.
In one form of the prior art, the substrate and the chip are both
separately, fixedly and precisely oriented and located. A transfer
mechanism, usually utilizing a vacuum probe as described above,
travels an invariable, repetitive path to pick up the chip and
place it at one selected position on the substrate. Then, a new
substrate and new chip are fed into their respective positions and
the operation repeats. In another form, the chips start out with a
degree of disorientation, for example, at random in a vibratory
feeder bowl. The feeder bowl, in the known manner, operates to
bring each chip in turn to a precise position. From that point, the
design is similar to the first category; although additional steps
to angularly orient the chip may be required intermediate the
feeder bowl and the precisely located substrate. Still other prior
art has combined these two categories.
In the device of U.S. Pat. No. 4,611,397, components are
successively placed by a hollow pick and placement spindle having
motion in the X-Y and Z planes. The spindle, using a vacuum, picks
up components individually from a plurality of precisely fixed
input stations, e.g., component trays, racks, feeder bowls, behind
the machine and delivers them to varied locations on the substrate
until the component placements have been completed. To assure
precision placement of components, the substrate edges and the
spindle housing provide X-Y reference points, and pivoted fingers
attached to the spindle homing center the chip on the spindle while
correcting for slight misorientations about the Z-axis i.e., less
than 45.degree., prior to placement, so the chip need not be
precisely positioned at the input station for selection.
Additionally, the support for the centering fingers is rotated
about the vacuum probe axis, while the fingers are closed on the
component, to provide control of the chip during angular
orientation as the circuit board layout requires.
In U.S. Pat. No. 4,458,412, a carousel provides random vertical
supply of taped components to a feeder assembly which feeds
individual chips onto a nozzle of a turret-type vacuum head at a
pick-up station. The turret-type head has four nozzles spaced
90.degree. apart about the central axis of the head. As the turret
is rotated, a chip is transported by a nozzle sequentially from the
pick-up station to a centering and testing station, a centering and
orienting station, and a placement station. Located between the
testing and orienting stations is a chip removal station for
ejecting defective or inverted chips. Sensors are located at the
adhesive and placement stations to detect defective P.C. boards so
that they may be bypassed. A controller, such as a digital
computer, provides additional monitoring and controls the operation
of the machine.
None of the prior art teaches a turret with multiple spindles
thereon whereby the turret addresses one or more supply stations to
load the spindles and then translates to a circuit board to place
the components selectively at various points on the circuit
board.
SUMMARY OF THE INVENTION
A turret assembly is movable in X and Y and a turret of the
assembly is rotatable to position a selected one of a plurality of
spindles at a transfer station of the turret. The selected spindle
is telescopic to pick a component from a supply point and to place
the component at a placement point on a circuit board or the like.
An assembly for squaring, centering, orienting, and/or testing a
component being held by another spindle of the turret is actuated
generally concurrently with extending of the selected spindle.
Alternatively, the spindle at the transfer station may be retained
in the retracted position during actuation of the squaring
assembly. Much time is saved by loading components on the plurality
of the spindles of the turret at one or more supply stations and
then placing all of these components without the need for
transferring back and forth between the supply and P.C. board.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial front elevation of the apparatus of the
invention.
FIG. 2 is a cross section as generally viewed in the direction of
arrows 2--2 of FIG. 1.
FIG. 3 is an enlarged cross section through the hub of the turret
in order to illustrate the control of various air pressure
condition on the tip of the spindle.
FIG. 4 is a cross sectional view through the spindle for
illustrating the structure by which the spindle is extended and
retracted.
FIG. 5 is a cross section as generally viewed in the direction of
arrows 5--5 of FIG. 4.
FIGS. 6 and 7 illustrate a structure by which the spindle at the
component transfer station of the turret may be held in the
retracted state during downward displacement of piston rod 40.
FIG. 8 is a schematic illustration of the fluid pressure lines and
controls for the apparatus of the invention.
FIG. 9 is a perspective illustrating an overall machine by which
the turret assembly may be translatable in X and Y between various
forms of supply stations and the path of travel of a circuit
board.
DETAILED DESCRIPTION OF THE INVENTION
With reference to the drawings, a component handling "pick" and
"place" head may be attached to an overhead arm (not shown) which
is translatable in X and Y so as to address various supply stations
with the head for retrieving or "picking" components therefrom and
subsequently "placing" the components at selected locations on a
printed circuit board or the like. Hub 74 is affixed to a main
bracket 20 of the pick and place head so as to support a turret 50
for rotation upon hub 74. A timing wheel 57 is attached to turret
50 so that turret 50 may be driven via timing belt 56, and servo
motor 52 according to a programreable controller, in order to
selectively position any of eight different spindles 64 for
component picking or placing and/or for squaring a component which
is already held by one of the vacuum spindles
Turret 50 has eight radially projecting tubular members 58 for
guidingly supporting the spindles 64. Referring to FIGS. 4 and 5,
each guide 58 has a lengthwise slot 60 through which a pin 66 of a
corresponding spindle 64 projects so as to ride in annular groove
24 of a ring 22 affixed to main bracket 20. The engagement of pins
66 in groove 24 maintains the retracted condition of the spindles
64 during rotation of turret 50.
A gap is provided in ring 22, and a portion of spindle displacer 42
extends into the gap and is slidable radially relative to hub 74.
Displacer 42 has actuate groove 44 which cooperates with annular
groove 24, when displacer 42 is in the upward or retracted
position, such that pin 66 of a spindle 64 may pass from the
annular groove 22 into arcuate groove 44 during rotation of turret
50. Thus, when a spindle 64 has been situated at the lowermost
position (with reference to FIGS. 1 and 2), it can be extended and
retracted by vertical movement of displacer 42.
Turret 50 has holes 70 corresponding to each spindle 64, with each
hole 70 accommodating a spool valve 68 therein. When a particular
spindle is positioned for extension and retraction via displacer
42, the corresponding spool valve 68 is displaceable (laterally as
viewed in FIG. 2). Extension of the piston rod of either air
cylinder C2 or air cylinder C3 will displace the spool valve so as
to provide negative, positive or neutral air pressure at the tip of
the extended spindle.
Spindle displacer 42 has a "dashpot" type of sliding attachment to
the lower end of the double ended piston rod 40 of cylinder C1.
This connection between displacer 42 and rod 40 allows spindle 64
to retract slightly against an air spring when the tip of spindle
64 is advanced into engagement with a component body during
"picking" of the component as well as when the component body
engages the printed circuit board during "placing" of the
component. Fluid is admitted to and evacuated from cylinder C1 via
fittings 46 and 48 according to the controller program.
In addition to picking and placing components, it is also possible
to square, center, and orient components about the longitudinal
axis of the vacuum spindle and to test electrical functioning of
the component. To that effect, a squaring assembly 90 is rotatably
mounted within a support bracket 92 which, in turn, is slidable
radially toward and away from turret 50 on main bracket 20 and is
biased toward turret 50 by a tension spring 94. Bracket 92 has a
screw 96 for engaging main bracket 20 so as to provide an
adjustable limit of movement of bracket 92 in one direction
(approximately 3/16 of an inch in a prototype of the device).
Bracket 92 is raised against the tension of spring 94 (to the
position of FIG. 2) by means of member 36 which is attached to an
upper end of double ended piston rod 40. Moving rod 40 so as to
lower member 36 allows spring 94 to bias bracket 92 downwardly
until screw 96 engages bracket 20, resulting in squaring ringers
100 of tooling 98 being positioned appropriately for subsequent
closing upon a component being held by the uppermost spindle
64.
Member 38 also is attached to the upper end of the double ended
piston rod 40 of cylinder C1. Actuation rod 102 normally is biased
upwardly by compression spring 104, and the normally opened
component engaging fingers 100 are closed when rod 102 is depressed
by member 38.
Gears 106 and 112 intermesh so that tooling 98 is rotatable about
its longitudinal axis, upon actuation of stepping motor 110
according to the programmed control, so as to reorient a component
which has been squared by and is still held in the fingers 100. Any
well known connection is provided between the hub of gear 106 and
rod 102 so that squaring fingers 100 are reorientable about the
longitudinal axis of tooling 98 in both the raised and lowered
conditions.
According to programmed control of an X-Y positioning system, the
pick and place head illustrated in FIGS. 1, 2, and 8 is moved to an
appropriate component: supply such as a reeled tape feeder. When so
positioned, spindle 64 is lowered by actuation of cylinder C1 to
move spindle displacer 42 from the solid line position to the
bottom most phantom line position of FIG. 2 for extension of
spindle 64. The dashpot-like connection between displacer 42 and
rod 40 allows displacer 42 to move (for instance, to the phantom
line middle position of FIG. 2) during picking and placing of
components in order to accommodate components of various
heights.
Thus, spindle 64 is extended to engage a component and hold it by
vacuum during retraction of the spindle by cylinder C1, whereupon
the turret 50 is rotated to position another spindle for the
subsequent picking operation. In a prototype of the invention, the
pick and place head is provided with a transmitter which is aligned
with a corresponding receiver located at each supply station during
picking of a component therefrom so as to control indexing of the
next component into position for a subsequent pick up. Having
picked up a component, turret 50 is rotatable to position another
spindle for "picking" from the same supply station. Alternatively,
the pick and place head could be moved in X and Y to position each
spindle at a different supply according to the needs of the user
and the program provided to the controller.
A reverse operation generally is performed in placing the component
at a selected location on the circuit board. Before, during, and/or
after X-Y positioning of the head, the turret is rotatable to
position any one of the eight spindles for placement of a component
at the selected location on the circuit board. Further, assembly 90
provides squaring, centering, orienting and/or electrical function
testing of the component held on the uppermost vacuum spindle 64
when lowermost spindle 64 is extended. Alternatively, it is
contemplated that relative movement could be provided between
assembly 90 and the uppermost spindle 64 to accomplish these
functions without the necessity of extending the lowermost spindle
64.
OPERATION
In preparation for performing the "picking" mode of operation: (a)
solenoids S1 and S2 are not actuated, (b) air is routed to the
bottom of cylinder C1 via valve VI to ensure that the picking
spindle is in the retracted position, (c) air is always available
to an input of valve V4, and a plunger thereof normally is spring
biased upwardly to prevent a fluid path through V4, (d) vacuum is
always available to the hub at 76, and (e) spool valve 68 is
displaced leftward from the position of FIG. 3 so that the tip of
the spindle is at atmospheric pressure.
For picking, the pick and place head is positioned in X and Y such
that the picking spindle 64 (the bottom most spindle as viewed in
FIGS. 1 and 2) is located above a component at a supply station.
Then, solenoid S1 is actuated to change the state of valve V1 such
that positive air is supplied to the top and evacuated from the
bottom of cylinder C1, resulting in extension of piston rod 40 and,
in turn, extension of spindle 64 by spindle displacer 42. With such
extension, member 36 depresses the plunger of valve V4 so that air
is ported through V4 to cylinder C2 by way of V2, whereupon
cylinder C2 causes the spool valve 68 to be displaced to the
position of FIG. 3. Thus, spool valve 68 completes a path between
hub 74 and spindle 64 for vacuum to hold a component on the tip of
the spindle.
Sensor 25 is actuated by member 36 during such extension of the
spindle 64 so that solenoid S1 is deactivated and a spring changes
the state of valve V1 to reroute positive air through valve V1,
causing cylinder C1 to retract the vacuum spindle 64 which is
holding a component. Complete retraction of the spindle is detected
by engagement of member 38 with a sensor 23 (FIG. 2) whereupon a
transmitter 27 and receiver 29 are used to detect presence or
absence of the component on the tip of the retracted spindle. If a
component is detected on the spindle tip, turret 50 is indexed (a
selectable amount according to the controller) so as to position
the next appropriate spindle for extension and pick up of a
component.
Hub 74 is provided with an annular groove 75 (FIG. 3) by which
vacuum is maintained on all of the spindles which are not in
position for extension by displacer 42. During rotation of turret
50, the corresponding spool valve 6 for each of these spindles 64
is retained (in the position of FIG. 3) by the friction of an
O-ring 69 with the internal diameter of port 70.
As many of the spindles 64 as desired may be loaded with components
by this "picking" procedure. It should be noted that member 36
clears the spring biased plunger of valve V4 when the spindle is
raised so as to disconnect the air path between V4 and V2 and
prevent actuation of cylinders C2 and C3.
For "placing" the components held on vacuum spindles 64, turret 50
is rotated selectively to present the appropriate spindle for
extension. Turret 50 can be rotated prior to, during, or after
repositioning of the overall head in X and Y so as to locate the
appropriate spindle over the appropriate placement location on a
circuit board. Solenoid S2 is activated to change the state of
valve V2 and is maintained in this activated state until all of the
placing operations are completed. Thus, a fluid path is made
available from valve V2 to cylinder C3 and the control portion of
valve V3, although no air is actually supplied via this path until
the plunger of valve V4 is engaged by member 36.
Next, solenoid S1 is activated to change the state of valve V1 so
that the supply and exhaust of air for cylinder C1 is reversed so
as to displace piston rod 40 and extend the appropriate spindle 64
for placement of a component on the circuit board. With lowering of
rod 40, member 36 depresses the plunger of valve V4 so that air is
ported therethrough to valve V2 which, in turn, ports air to
cylinder C3 and to the control inlet of valve V3. Thus, cylinder C3
displaces spool valve 68 (to the left as viewed in FIG. 3) so as to
provide a path between positive air inlet 78 of hub 74 and the
spindle 64. The control air supply to valve V3 causes a pulse of
air which was previously stored therein to be supplied to the inlet
78 of hub 74 so that an "air kiss" ensures release of the component
from the tip of spindle 64 during placing of the component. Valve
V3 automatically resets to capture another pulse of air
therein.
Sensor 25 detects the lowered position of member 36 so as to
indicate that the spindle 64 is fully extended and that the
controller may deactivate solenoid S1. Thus, the state of valve V1
is changed to reroute air therethrough for retraction of the
spindle. It may be advantageous to program a delay for changing of
solenoid S1 when the spindle is fully extended so as to allow for
settling time of the spindle and/or additional time for orienting
or testing another component by assembly 90.
With the spindle retracted, turret 50 is rotated to link the next
appropriate spindle 64 with displacer 42, and the pick and place
head is repositioned over the circuit board for placing the next
component thereon. This process is continued as required for
placement of the other components. It should be noted that the
retracted position of the spindle is detected by sensor 23 being
activated by member 38, at which time transmitter and receiver
system 27, 29 is used to detect the presence or absence of a
component on the spindle.
During each displacement of double ended piston rod 40 of cylinder
C1, a bracket 92 is lowered and fingers 100 of a squaring assembly
90 are closed upon any component which is held by the uppermost
spindle 64. For an understanding of the structure and operation of
assembly 90, the reader is referred to U.S. Pat. No. 4,721,907
illustrating tester fingers utilized in testing electrical
functioning of a component during squaring and centering thereof
and U.S. Pat. No. 4,611,397 illustrating centering fingers which
may be rotated about a central longitudinal axis of the device so
as to reorient the component. It is contemplated in the instant
invention to incorporate the squaring, centering, and orienting
feature into the device of U.S. Pat. No. 4,721,907 or,
alternatively, to incorporate the electrical function testing
feature into the device of U.S. Pat. No. 4,611,397, in order to
provide the functions required of assembly 90. It is preferred that
the component remains on the tip of the spindle 64 while being
operated on by assembly 90, as practiced at the test and orient
stations of U.S. Pat. No. 4,458,412, but without extending spindle
64 for these functions.
Referring to FIGS. 6 and 7, a spindle located at the component
transfer station of the turret may be selectively extended or held
in the retracted position during lower of piston rod 40 which, in
turn, actuates the squaring assembly 90. In FIG. 6, the displacer
42' acts in much the same way as the earlier described displacer
42. However, in FIG. 7, during lowering of piston rod 40, air is
supplied via hose 43 so as to prevent lowering of displacer 42'
along with rod 40. Thus, a spindle located at the component
transfer station of the turret assembly will not be extended during
actuation of squaring assembly 90.
The following claims are intended to cover all of the generic and
specific features of the invention herein described and all
statements of the scope of the invention which as a matter of
language, might be said to fall therebetween.
* * * * *