Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROUND OF THE INVENTION
This invention is concerned with a stacking device and packaging
maehine for headed tubular fasteners~ In particular the invention con-
cerns a staeking device suitable for use in stacking headed tubular
fasteners, sueh as rivets, in a column one-above-the-other head to tail,
5 such a staeking device forming part of a packaging machine for such
fasteners .
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DE~SCRIPTION OF TFIE ~RIOR ~\RT
In European Patent Specification No . 78300382 . 5 (Publ;cation No .
1343), there is described an assemblage or packet of hollow rivets oom-
prising a column of the rivets assembled head to tail on a sleeve. This
5assemblage is for use in loading hollow rivets on to a headed mandrel
so that they CAn be set in a pull-through blind riveting operation. In
such an operation, a column of, for example, 30 to 60 rivets is assembled
on a mandrel, the mandrel is inserted in a blind riveting tool which has
means for gripping and pulling the mandrel through Q rivet to set it, and
10the rivets in the column are set by successive operations of the tool.
There is a need for a machine which can make the above-mentioned
assemblages or packets and such a machine requires a stacking device
to stack the rivets.
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OBJECTS OF TTIE INVENTION
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It i9 an object of the present invention to provide a stacking device
suitable to form part of a machine for making an assemblage or packet
of hollow rivet9.
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SUMMARY OF T~E INV E~NTTON
There is hereinafter described in detail with reference to the accompany-
ing drawings a machine for making an assemblage or packet of hollow
rivets which is illustrative of the invention. The illustrative machine
5 comprises a stacking device, also itself illustrative of the invention, which
device stacks headed tubular fasteners (viz. hollow rivets) in a column
one-above-the-other head to tail. The illustrative device comprises
feeding means including a vibratory hopper, vibrating means operable
to vibrate the hopper, a raceway arranged to collect and feed rivets
10emerging from the hopper, and a substantially hori~ontal guide to which
the rivets are advanced from the raceway one after the other with their
shanks substantially vertical by the operation of the feeding means.
The illustrative device also comprises a collector which defines a sub-
stantially vertical passage which has its upper end adjacent an open exit
15 end of the guide. The passage has transverse dimensions such that
rivets falling into the passage are constrained to ~orm a column one-
above-the-other with their shanks substantially in alignment. Rivets
leaving the guide through the exit end fall into the passage and form a
column in the passage.
20 In order to ensure that rivets leaving the exit end of the guide do not
form a jam in the end of the passage, the illustrative stacking device com-
prises air blowing means operable to cause the rivet nearest the exit
end of the guide to accelerate relative to the other rivets in the guide and
thereby separate l:hat rivet from 9aid other rivets to prevent jams. The
25 air blowing means includes a nozzle positioned adjacent the guide and
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1 arranged to direct air blown through the nozzle towards the exit end of
the guide. When air is blown through the nozPIe, the rivet nearest the
exit end of the guide is caused to accelerate relative to the other rivets
in the guide and is thereby separated from said other fasteners thereby
5 preventing jamming so that the fastener can fall into the guide.
The invention provides a stacking device suitable for use in stacking
headed tubular fasteners in a column one-above-the-other head to tail,
the device comprising feeding means including a substantially hori-
zontal guide to which the fasteners are advanced one after the other with
lO+heir shanks substantially vertical, a collector which defines a substan-
tially ver+ical passage which has its upper end adjacent an open exit end
of the guide so that fasteners leaving the guide through the exit end fall
into the passage, the passage having transverse dimensions such that
fasteners falling into the passage are constrained to form a column one-
15 above-the-other with their shanks substantially in alignment, and air
blowing means including a noæzle positioned adjacent the guide so that,
~vhen air is blown through the nozzle, the fastener nearest the exit end of
the guide is caused to accelerate relative to the other fasteners in the
guide and is thereby separated from said other fasteners to fall into the
20 passage.
In order to insert the sleeve of a pacl~et or assemblage of rivets
through a column of rivets in the passage of the illustrative stacking
device, the illustrative machine alfio comprises an elongated mandrel
which is threaded through the column and then withdrawn pulling the
25 sleeve therewith so that the sleeve is threaded through the column.
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There now follows a detailed description, to be read
with reference to the accompanying drawings, of the illus-
trative machine aforementioned. It is to be understood
that the illustrative machine and the illustrative stacking
device which forms part thereof have been selected for
description by way of example and not of limitation of the
invention.
According to a broad aspect of the present invention
there is provided a stacking device suitable for use in
stacking headed tubular fasteners in a column one-above-the-
other head to tail. The device comprises feeding means
including a substantially horizontal guide to which the
fasteners are advanced one after the other with their
shanks substantially vertical. A collector is provided and
defines a substantially vertical passage which has its
upper end adjacent an open exit end of the guide so that
fasteners leaving the guide through the exit end fall into
the passage. The passage has transverse dimensions such
~; that fasteners falling into the passage are constrained to
form a column one-above-the-other with their shanks sub-
stantially in alignment. Air blowing means is provided
and includes a nozzle positioned adjacent the guide so
` that, when air is blown through the nozzle, the fastener
`~ nearest the exit end of the guide is caused to accelerate
relative to the other fasteners in the guide and is thereby
separated from t~e-other fasteners to fall into the passage.
~eans is associated with the vertical passage of the
collector for packaging a-column of stacked fasteners.
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The packaging means comprise means for moving a mandrel
upwardly, longitudinally through a column of fasteners
formed in the passage.
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BRIEF DESCRIPTION OF THE DRAWINCIS
Figure 1 is a perspective view of the illustrative machine;
Figure 2 is a perspective view, on a larger scale than Figure 1,
of a portion of the illustrative stacking clevice of the illustrative machine;
5 Figure 3 is an elevational view, partly in sect;on and on a larger
scale than Figure 2, taken in the direction of the arrow III in Figure 2;
Figure 4 is an e~ploded perspective view of a portion of the illustrative
stacking device; and
Figure 5 is a side elevational view of a portion of the illustrative
10stacking device~
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DESCRIPTION OF T~IE PREFERRED EI~BODIMENTS
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The illustrative machine (Figure 1) i8 ~or making an assemblage or
packet of hollow rivets R which have heads ~I and shanks S (Figure 3) .
The machine comprises a frameworl; 10 ~which supports a table 12
5 (Figure 1) . The machine also comprises the illustrative stacking device
which is supported by the framework 10 and the table 12.
The illustrative stacking device is for use in stacking the rivets R
in a column one-above-the-other head to tail. The device comprises
feeding means including a raceway 20 arranged to guide rivets R with
10 their heads H in a channel and their shanks S projecting through a guid-
ance slot 22 of the raceway 20 (Figures 1 and 2) . The rivets R are advanced
one after the other along the raceway 20 to a guide 14 where their shanks S
are substantially vertical. The feeding means also comprises a hopper
16 supported above the table 12 on flexible mountings 18 so that vibration
15 means of the hopper 16 can cause the hopper 16 to vibrate. The hopper 16
is of conventional design and is arranged when vibrating to feed rivets
R placed in the hopper 16 one at a time into the raceway 20 of the feeding
means. The raceway 20 is supported by a bracket 21 mounted on a flexible
rubber bearing 23 mounted on the framework 10. The rivets R leaving
20 the hopper 16 have their shanks pointing downwards but the raceway 20
makes a 180 degree turn so that the rivets R are inverted and their shanks
then point upwards. A lower end portion of raceway 20 forms the
substantially horizontal guide 14 to which the rivets R are fed one after
the other with their shanks pointing upwards. The guide 14 is thus
25 arranged to hold the rivets with their heads ~ ]owermost. Rivets R
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I pass into the guide 14 from the raceway 20 when the hopper 16 and the
raceway 20 are vibrated by the vibrating means 18. When vibration
ceases, the rivets in the guide 14 come to rest because the guide 14 i9
substantially horizontal.
S The illustrative stacking device also comprises a collector 24 which
defines a substantially vertical cylindrical passage 26 which has its
upper end adjacent an open exit end of the guide 14 so that rivets leaving
the guide 14 through the exit end fall into the passage 26. Because the
rivets are held in the guide 14 with their heads lowermost, when a rivet
IOleaves the guide 14 through the exit end thereof, it falls head-first
into the passage 26. The passage 26 has transverse dimensions such
that rivets falling into the passage 26 are constrained ts) form a column one-
above-the-other with their shanks S substantially in alignment (Figure 3),
i.e. the passage 26 is of slightly greater diameter than the heads H of
the rivets R. The collector 24 comprises two passage-defining members
28 and 30 each having a semicircular groove therein which defines half
of the passage 26. The member 28 is rigidly mounted on the framework 10
but the member 30 is slidable on two guide rods 32 (Pigures 1 and 2) mounted
on the framework 10 towards and away from the member 28 under the action
21)of a pneumatic piston and cylinder assembly 34. The member 30 can
be moved by operation of the assembly 34 between a closed condition of the
collector 24 in which the two members 28 and 30 co-operate to define the
passage 26 (Figure 1) and an open condition in which a column of rivets
stacked in the passage 26 can be removed therefrom (Figures 2 and 5) .
~5 When the collector 24 is in the open condition, the member 30 operates
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I a mechanically-operated pneumatic valve 36 (Figure 1) mounted on the
framework 10. The purpose of the valve 36 will appear from the description
below of the operation of the illustrative machine.
The collector 24 also comprises detecting means operable to detect
5 whèn a predetermined number of rivets has been stacked in the passage
26. The detecting means comprises a photo-electric cell 3~3 mounted
at one side of the passage 26 on the member 28 and arranged to receive
light from a light source provided by a lamp 40 mounted at the other
side of the passage 26 on the other passage-defining member 30. The
- 10 photo-electric cell 38 and the lamp 40 are arranged at an angle to the
direction of movement of the member 30 so that the cell 38 and lamp 40
are only aligned in the closed condition of the members 28 and 30. Thus,
light is received by the photo-electric cell 38 only when the collector 24
is in its closed condition and when the light from the lamp 40 is not
15 intercepted by a rivet in the passage 26. The photo-electric cell 38 is
arranged to signal that the predetermined number of rivets is in the
passage. It is operative when the collector 24 is in the closed condition
and when the light from the lamp 40 is interrupted for a predetermined
time, which time is longer than the time which a rivet takes to fall past
20 the photo-electric cell 38.
When a rivet R falls into the passage 26, it comes to rest, if it is
the first rivet in a column, with its head resting on a catcher 37 (Figure 5) .
The catcher 37 i9 mounted on a lower portion Or the member 30 of the
collector 24 and is horseshoe-shaped with an opening 39 therein facing
25 the member 28. Subsequent rivets R come to rest on top of previous
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I rivets. A guidance tube 41 is mounted on a lower portion of the member
28 of the collector 24 closing the passage 26 below the catcher 37 except
~or the bore 43 of the tube 41. The tube 41 carries a hook 45 which projects
towards the member 30 when the collector 24 is in its closed condition.
5 The hook 45 also projects upwardly to a point just below the level of the
catcher 37.
The illustrative machine also comprises an elongated mandrel 42
(Figures 3 and 5) supported on the piston rod 44 (Figure 1) of a pneumatic
piston and cylinder assembly 46 mounted on the framework 10 beneath the
lOcollector 24. The mandrel 42 has transverse dimensions such that it can
be threaded through a column of rivets formed in the passage 26. The
assembly 46 provides moving means operable to move the mandrel 42
upwards longitudinally thereof so that the mandrel 42 is threaded through
the column as aforesaid and to withdraw the mandrel 42 from the column
1~ again (Figure 1) . The mandrel 42 is mounted on a bracket 48 which projects
sideways from the piston rod 44 into a groove S0 in a block 52 mounted
on the framework 10 . The groove 50 acts as a guide for the mandrel 42
and connects with the lower end of the tube 41 (Figure 5) so that the mandrel
42 can enter the passage 26 by passing through the bore 43 in the tube 41.
20 The mandrel 42 has an upper free end portion 54 of reduced diameter
: (Figure 3) which terminates in a pointed end 56. The operation of the
assembly 46 is arranged to move the mandrel 42 upwards through a
- column of rivets in the passage 26. In order to minimize the risk that
the mandrel 42 will jam against a rivet during its passage through a
25 column, the assembly 46 is so arranged that, upon tke pressure ris;ng
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I in the cylinder of the assembly 46 which occurs when the mandrel 42
meets resistance, the air supply to the assembly is cut off so that the piston
and mandrel 42 fall under their own weight until the pre&sure falls again
whereupon the air supply is restored. This arrangement assists the
S mandrel 42 in passing through the r;vets R in the column since it allows
time for the rivets to re-align themselves slightly as the mandrel 42 passes
through them. The fact that the mandrel 42 enters the column from below
assists in its passing through the column since the rivets R can be lifted
relative to one another during re-alignment of the rivets R as the mandrel
10 42 passes therethrough .
The piston rod 44 of the assembly 46 carries a crosshead 58 which
is arranged to operate three mechanically-operated pneumatic valves
60, 62 and 64 mounted on the *amework 10. The valves 60 and 62 are
arranged to be operated when the mandrel 42 is completely out of the
IS column of rivets and the valve 64 is arranged to be operated when the
mandrel 42 is fully in the column with the reduced end portion 54 thereof
projecting beyond the top of the column. The purpose oE each of the
valves 60, 62 and 64 will appear from the description below of the op-
eration of the illustrative machine.
20 The illustrative stacking device also comprises holding means S6
~Figures 1 and 5) arranged to hold a sleeve 68 made of resilient plastics
material with an open end of the sleeve adjacent to the upper end of the
passags 26 and to resist movemsnt of the slseve 68 away fFom the passage
26. The reduced end portion 54 of the mandrel 42 has transverse dlmen-
25 sions such that it can enter the sleeve 68 causing the sleeve 6~ to expand
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I and grip the portion 54. Thus, after passing through the column of
rivets in the passage 26, the portion 54 can enter the sleeve 68 held by
the holding means 66 so that the sleeve 68 expands and grips the portion
54, and, upon operation of the assembly 46 to withdraw the mandrel 42
5 from the column of rivets, the sleeve 68 :is pulled through the column
so that the rivets become threaded on the sleeve 68.
The details of the holding means 66 appear from Figure 3. The holding
means 66 mounted on a block 70 supported by the member 28 of the
collector 24. The holding means comprises a vertical tube 72 having a
lObore 74 therethrough a bottom end portion of which tapers outwardly. An
-inner tube 76 is vertically slidable in the bore 74 being urged upwardly
by a spring 78 which acts between a shoulder in the bore 74 and a shoulder
on the inner tube 76. The movement of the inner tube 76 is restrained
by a transverse pin 80 mounted on an upper portion of the tube 72 and
15 extending through an elongated slot 82 in the inner tube 76; the pin 80
has a vertical bore 81 therethrough for the passage of the sleeve 68. A
lower end portion of the inner tube 76 has three equally-spaced radial bores
84 extending through the wall thereof at the same distance from the bottom
of the tube and a ball 86 is contained in each of the bores 84, each ball
2~) 86 engaging the outwardly tapering portion of the bore 74 and extending
into the bore through the inner tube 76.
The sleeve 68 is supplied to the illustrative stacking device from a
: reel 88 mounted for rotation about a horizontal axis on a bracket 90
; mounted on the framework-10. The reel 88 is provided with a pneuma-
25 tically-operated friction brake 92 which prevents iiree rotation of the
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1 reel 88 but allows the sleeve 68 to be drawn ~rom the reel 88 by pulling
on the sleeve 68 thereby rotating the reel 88. I;rotn the reel 88, the
sleeve 68 passes to a pulley 94 which is rotatable about a horizontal axis
with its io~,ver portion immersed in lubrication oil contained in an oil
S tank 96 mounted on a bracket 98 on the table 12. The sleeve 613 makes
a complete turn around the pulley 94 so that it receives a thin coating
of oil from the tank 98. The lubrication oil is transferred to the rivets R
from the sleeve 68 and will assist the setting of the rivets. From the pulley
94, The sleeve 68 passes to a guide pulley 100 and then descends vertically
IOthrough the inner tube 76, the bore 81 in the pin 80, between the balls
86 and into a vertical bore 102 in the block 70 (Figure 3) .
The operation of the holding means 66 will now be described. The
spring 78 urges the inner tube 76 upwardly pulling the balls 86 towards
the narrow upper end of the outwardly tapering portion of the bore 74. The
15 balls 86 are thus urged together and grip the sleeve 68 preventing upward
movement thereof. However, if the sleeve 68 is pull&d downwardly, the
balls 86 are drawn towards the wide lower end of the tapering portion,
against the action of the spring 78, releasing their grip and allowing
movement of the sleeve 68 downwardly. The region 69 (Figures 3 and 5)
20 of the sleeve 68 which the balls 86 grip becomes deformed by the balls
86 in such a manner that, although it does not prevent the sleeve 68
passing through rivets R, it acts to prevent rivets R accidently falling
off the sleeve 68.
l~he lower end of the bore 102 in the block 70 communicates with
~;25 a slot 104 (Figures 3 and ~) formed between the block 70 and a block 106
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I mounted on the member 28. The block 106 also ha~ a vertical slot 108
therein which receives the shanks S of rivets R as they leave the guide 14.
A knife 110 mounted on a block 112 carried by the member 30 moves in
the slot 104 so that i~ cuts through the sleeve 68 immecliately below the
S block 70 as the member 30 moves away from the member 28.
A pneumatic piston and cylinder assembly 114 is mounted on a support
plate 116 mounted on the framework 10 (Figure 1) . The piston rod of the
assembly 114 carries a closure member 118 (Figure 4) which i8 slidable
in a slot 120 formed in upper portions of the members 28 and 30 and
lOpartially in the block 70. The closure member 118 is movable by the action
of the assembly 114 to a forward position in which it closes the upper end
of the passage 26 preventing further rivets from falling into the passage
26. The closure member 118 has a vertical bore ]22 therethrough in which
the sleeve 68 is received and a horizontal bore 124 therein connecting
15 with the bore 122. The piston rod of the assembly 114 also carries a cross-
head 121 arranged to operate a pneumatic valve 123 for a purpose to be
described . `
;; A pneumatic piston and cylinder assembly 126 (Figure 1) is mounted
on a bracket 128 which extends forwardly from the framework 10. The
20 piston rod 130 (Figures 3 and 4) of the assembly 126 carries a plunger
132 arranged, under the action of the assembly 126, to pass through a
groove 134 in the end of the guide 14 and enter the bore 124 in the closure
member 118 engaging the sleeve 68 in the bore 122 and flattening the sleeve
~, 68 against the wall of the bore 122 to deform the sleeve 68. The assembly
;: 25126 forms deformi:ng means operable to deform an end portion of the sleeve
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1 68 after the sleeve 68 has been threaded through the column of rivets
in order to minimize the risk of the rivets falling off the sleeve 68.
The illustrative stacking devi~e also comprises air blowing means
including three nozzles 136, 138 and 140 (Figure 4) positioned adjacent
S the guide 14. The nozzles 136 and 138 enter oppc~site sides of the guide
14 and the nozzlc la~0 enters the guide 1~ ~rom below. The nozzles 136,
138 and 140 are so positioned that, when air is blown through the nozzles,
the rivet R nearest the exit end of the guide 14 is caused to accelerate
relative to the other rivets in the guide 14 and is thereby separated
IOfrom said other fasteners to fall into the passage 26. The air blowing
means ensures that rivets R entering the passage 26 do not interfere
with one another causing a jam.
The illustrative machine also comprises ejecting means comprising
a nozzle 142 (Figure 5) positioned to one side of the collector 24 and
IS arranged to direct air on to a packet of rivets R in the collector 24,
when the collector is in its open condition, to eject the packet from the
collector 24.
A cycle of operation of the illustrative machine will now be described
starting from the condition shown in Figure 1. In this condition, the
20 guide 14 and the raceway 20 contain rivets R which have previously
been fed from the hopper 16 by operation of the vibrating means. The
collector 24 is in its closed condition and the holding means 66 is
holding the open end of the sleeve 68 above the passage 26. The piston
and cylinder assemblies 46 and 114 are respectively holding the mandrel
25 42 and the closure member 118 clear of the passage 26.
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In the operation of the illustrative machine, the air blowing means
is operated blowing air ~hrough the nozzles 136, l3~ and 140 thereby
causing rivets to fall one at a time into the passage 26 and, at the same
time, the vibrating means of the hopper 16 is operated to ensure a con- .
S tinuous supply of rivets to the guide 14. The t`irst rivet which falls
into the pa6sage 26 comes to rest with its head on the catcher 37 and
subsequent rivets pile up on the first rivet to form a column one-above-
the-other with their shanks substantially in alignment.
When the column of rivets in the passage 26 reaches the photo-
0electric cell 38, the cell 38 creates a signal which causes the vibrating
means and the air blowing means to be turned off thereby cutting off
the feed of rivets to the pasage 26. The signal also causes the assembly
114 to move the closure member 118 forwardly into a position in which it
ensures that no further rivets l`all into the passage 26. Operation of the
lS assembly 114 causes the valve 123 to be operated and this causes the
assembly 46 to move the mandrel 42 upwardly, so that the mandrel 42
passes upwardly through the column of rivets and its reduced end portion
54 enters the sleeve 68 held by the holding means 66 so that the sleeve
68 grips the portion 54. As the portion 54 is gripped by the sleeve 68,
~: ~ 20 the crosshead 58 operates the valve 64 which causes the assembly 46
to reverse its direction of movement.
` The assembly 46 now withdraws the mandrel 42 from the column of
` rivets thereby drawing the sleeve 68 through the column. When the
sleeve 68 reaches the tube 41 at the lower end of the passage 26, the
25 sleeve 68 is stripped off the mandrel 42 by the upper end of the tube
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1 41 as the reduced end portion 54 withdraws into the bore 43 in the tube
41. The crosshead 58 now operates the valves 60 and 62 with the valve
60 being operated before the valve 62.
Operation of the valve 60 causes the assembly 126 to operate sending
5 the plunger 132 through the bore 124 into contact with the sleeve 68 in
the bore 122. The plunger 132 deforms the sleeve 68 leaving it with a
flattened region (not shown) which acts to prevent the rivets R from
accidently falling off the sleeve B8. The plunger 132 is returned when
the crosshead 58 releases the valve 60 which it does immediately before
10 operating the valve 62.
Operation of the valve 62, causes operation of the assembly 34 to
move the collector 24 to its open condition. As the member 30 moves, the
knife 110 cuts off the sleeve 68 and the hook 45 draws the lower end of
the sleeve 68 out of the opening 39 in the catcher 37~ The movement of
1~ the member 30 continues until the valve 36 is operated thereby whereupon
a blast of air from the nozzle 142 ejects the rivet packet from the passage
26. The operation of the valve 36 also causes the assembly 34 to reverse
its movement so that the collector 2'1 is returned to its closed condition
ready for a fuxther cycle of operation of the machine. When the collector
20 24 again reaches its closed condition, the photo-electric cell 38 again
receives light from the lamp 40 and produces a signal which causes
operation of the assembly 114 to withdraw the closure member 118
from the passage 26, the vibrating means to re-start, and also air to
be supplied to the air blowing means so that air is blown through the
25 nozzles 136, 138 and 140. The illustrative machine can now repeat its
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I cycle of operation to make another rivet packet.
If desired the illustrative stacking device may be modified so that,
instead of the holding means 66, the device may comprise ~leeve feeding
means operable to feed the sleeve 68 around the mandrel 42 while the
S mandrel 42 is threaded through the column of rivets 90 that the sleeve
68 becomes threaded through the column over the mandrel 42. The
mandrel 42 could then be withdrawn lea~ving the sleeve 68 threaded
through the column.
lO Having thus described our invention, what we claim as new and
desire to secure by Letters Patent of the United States i~:
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