Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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The present invention relates to improvements in a method and
apparatus for separating individual assembly parts from a coherent mass
of such parts resting on a support.
In assembly operations using such assembly parts as helical
springs, contact and other electrical components, clips, pins, screws,
bolts, small tubes, hooks, rings and the like, a major problem exists in
delivering single assembly parts to the assembly line from a coherent mass
of such parts, in which the parts randomly adhere to each other and may
be completely entangled, as in the case of coil springs or hooks and other
assembly parts of complex configuration.
Various methods and apparatus have been proposed for singling
such assembly parts but they are effective only to a limited extent, being
generally capable only of singling relatively loosely coherent parts or
parts of a specific type or sturdy parts which are not readily damaged
during the disentangling operation. When assembly parts of complicated
shape, such as wire clips with multiple bends, are handled by the known
singling procedures, the parts are frequently further snagged rather than
being disentangled, forming additional clusters rather than resolving them
into individual parts. Furthermore, even where the assembly parts are
singled, the number of individual parts delivered from the coherent mass
is subject to great variations, making it necessary to provide compensating
storage devices downstream from the singling station to assure a steady
delivery of the single parts to the assembly line.
Generally, vibratory bowls or plates have been used for singling
parts, such as disclosed in U.S. patents Nos. 2,765,900 and 3,788,456,
but on the whole these devices are effective only for relatively simply
shaped assembly parts which are not strongly entangled. While the
vibration of the support for the coherent mass of parts causes the
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support to shift in relation to the mass, the same portion of the mass
continuously contacts the support. Experience has shown that this tends
to lead to compression and, therefore, stronger coherence of the parts in
the mass rather than to its resolution into single parts.
In U.S. patent No. 4,063,642, it has been proposed to separate
individual assembly parts from a coherent mass of the parts by first
separating the mass into small clusters by a brush conveyor which moves
these small clusters of parts into a whirlpool chamber where the clusters
are resolved into single parts by a blast of air which ejects the singled
parts and moves them to an orienting station where the single parts are
oriented and conveyed to an assembly line or the like. This apparatus
has been effectively used in commercial practice but, for parts with
multiple bends or forming initially loose clusters having many empty
cavities in their interior, the brush conveyor sometimes tends to make
the clusters of parts denser rather than resolving them and the apparatus
does not always work as efficiently as may be desired.
U.S. patent No. 3,118,564 discloses an apparatus for separating
helical springs from an entangled mass thereof wherein a mass of springs
is introduced into the open upper end of a dielectric tube, a magnet is
successively energized and de-energized to lift the mass and to permit
it to fall, the resultant agitating effect causing individual springs
to be separated. The individual springs adjacent the lower end of the
mass are permitted to roll outwardly by the vibration of the overlying
mass to the periphery of a support plate from which they can be removed.
This apparatus can be used only with assembly parts of magnetizable
material and, in practice, since the lower portion of the coherent mass
in contact with the support remains unchanged by the magnetic lifting and
lowering thereof in the tube, the weight of the mass will tend to prevent
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effective disentanglement and the outlet path will readily be jammed.
U.S. patent No. 3,729,096, discloses a slatted rotary drum for
separating the leaves of a herb from the s-eeds and twigs thereof. As
the drum is rotated, the leaves drop through the slots ~etween the drum
slats while the seeds and twigs are retained in the drum.
German Offenlegungsschrift No. 2,513,331 discloses a conveyor
arrangement for removing individual parts from a random mass thereof,
which comprises a rotary drum with peripherally arranged entrainment
elements which are designed to catch individual parts and entrain them
upwardly as the drum rotates, the upwardly entrained parts being then
released and removed on a chute.
It is the primary object of the invention to provide a simple
and universally effective method and apparatus for separating individual
assembly parts of all types and shapes from a coherent mass of the parts.
It is another object of this invention to provide such a method
and apparatus wherein the singled assembly parts are delivered at a sub-
stantially uniform rate per time unit.
The above and other objects are accomplished according to one aspect
of the present invention by randomly subdividing the mass of assembly parts
into clusters of these parts by continuously and successively lifting
randomly selected ones of the clusters off the support on which the coherent
mass of the parts rests and dropping the lifted clusters thereon until the
mass is resolved into the clusters and the clusters are further resolved,
the continuous and successive lifting and dropping of the clusters causing
continuously changing portions of the mass and clusters to rest on the
support and the support being continuously and successively relieved of
the weight of the randomly selected lifted clusters of assembly parts. The
resolved clusters are then singled into individual assembly parts and the
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individual assembly parts are removed from the support. Preferably, the
individual assembly parts removed from the support are orientated while
the parts are conveyed away from the support. This method is fully
effective with assembly parts which are entangled with each other in the
coherent mass, in which case the mass is resolved by partially disentangling
the parts to form the clusters and the clusters are resolved by further
disentangling the parts.
- According to another aspect of this invention, an apparatus is
provided for separating individual assembly parts from a coherent mass of
the parts, which comprises a receptacle for storing the mass of the parts,
the receptacle including a support for the mass of the parts and the support
defining an opening normally covered by the mass. Mechanical means is
arranged in the receptacle for continuously and successively lifting
random clusters of the assembly parts out of the mass and away from the
opening in the support and for dropping the lifted clusters on the support
whereby the mass is resolved into the random clusters and the clusters are
further resolved by the impact of the dropped clusters on the support.
The opening in the support is of a cross section permitting individual
ones of the assembly parts from the resolved clusters to pass therethrough
by gravity. Preferably, conveyor means is arranged for orienting
individual ones of the assembly parts removed from the support through
the opening.
The continuous and successive lifting and dropping of clusters of
parts out of the coherent mass thereof, as well as the sliding of the mass
and clusters along the inclined support of the receptacle constantly
shifts the relative positions of portions of the mass and of the clusters
to each other and to the support, and these cyclical random movements are
very effective in resolving the mass and the clusters so that individual
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parts can he removed ky gravity through a bottom outlet opening in the
receptacle support at a sufistantially constant rate. If the assembly
parts are sturdy enough to resïst damage, it may be desirable to agitate
the clusters while they are lifted out of the coherent mass, thus further
loosening entanglements.
The above and other objects, advantages and features of the
present invention will become more apparent from the following detailed
description of certain now preferred embodiments thereof, taken in
conjunction with the accompanying drawing wherein
FIGURE 1 shows a side view of one embodiment of the apparatus,
with a side wall of the housing enclosing the apparatus removed to show
the working elements of the apparatus;
FIGURE 2 is a sectional view along line II-II of FIGURE l;
FIGURE 3 schematically illustrates another embodiment of the
apparatus, with the working elements in the interior of the supporting
frame of the apparatus shown in broken lines;
FIGURE 4 is a side elevational view of the apparatus of FIGURE 3,
with a side wall of the housing removed; and
FIGURE 5 shows an end view of a modified rotary drum for use in
2a the apparatus of FIGURES 3 and 4.
Referring now to the drawing and first to FIGURES 1 and 2, the
apparatus for separating individual assembly parts from a coherent mass
of the parts (not shown) is shown to comprise receptacle 1 for storing
the coherent mass of assembly parts. The receptacle includes a support
for the mass of assembly parts and the suppor~ defines an opening normally
covered by the mass. In the illustrated embodiment, the support comprises
two inclined support plates 3 defining slot-shaped discharge opening 2
therebetween. The support plates form a trough-shaped bottom of receptacle
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1 and the discharge opening is defined in the bottom of the receptacle.
A mechan;cal means 8, 9 is arranged in receptacle 1 for con-
tinuously and successively l;fting random clusters of assembly parts out
of the mass ;n the receptacle and away from opening 2 in support 3 and
for dropping the lifted clusters on the support whereby the mass is
resolved into the random clusters and the clusters are further resolved by
the impact of the dropped clusters on support 3. In the illustrated
embodiment, the mechanical means comprises device 9 for alternately
gripping and releasing successive random clusters and drive 8 for con-
tinuously and successively moving gripping and releasing device 9 vertically
towards and away from opening 2. Device 9 comprises reciprocable gripper
tongs~or jaws capable of gripping and releasing clusters of assembly parts
upon reciprocation of the gripper tongs or jaws while drive 8 moves the
device up and down, the illustrated drive being a pneumatically operated
cylinder-piston unit.
In this manner, the mass of assembly parts resting on support 3
is randomly sub-divided into clusters of the parts by continuously and
successively lifting randomly selected clusters off the support and
dropping the lifted clusters thereon until the mass of the assembly parts
is resolved into the clusters and the clusters are further resolved on
impact. The continuous and successive lifting and dropping of the
clusters causes continuously changing portions of the mass and clusters
to rest on support 3 as the mass glides therealong as the clusters are
lifted and dropped, and the support is continuously and successively
relieved of the weight of the randomly selected lifted clusters of
assembly parts.
Opening 2 in the support is of a cross section permitting
individual ones of the assembly parts from the resolved clusters to pass
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therethrough by gravity. In the illustrated embodiment, the cross
section of the opening is large enough to perm;t a plurality of the
assembly parts to pass therethrough and a driven, roller-shaped rotary
brush 4 is mounted in opening 2 for singling the assembly parts in the
resolved clusters dropped thereon and for discharging the singled assembly
parts through opening 2. For this purpose, the rotary brush, whose axis
of rotation extends substantially parallel to slot-shaped opening 2 and
whose rotary axle is journaled in bearings in the side walls of receptacle
1, has bristles so shaped and arranged as to single the assembly parts,
i.e. to separate the parts in the resolved cluster individually, the
effective length of the bristles being so selected as to obtain a uniform
discharge of the individually separated assembly parts through outlet
opening 2. If the rotary brush is replaceably journaled in the receptacle,
it may be exchanged and replaced by a brush with another type of bristle
arrangement and length to adapt the apparatus for singling different types
of parts and/or for controlling the rate of discharge of the singled parts.
In this manner, the resolved clusters are singled into individual assembly
parts and the individual assembly parts are removed from support 3.
The singled assembly parts fall from outlet opening 2 onto baffle
and deflecting bars 5 mounted in the path of the parts underneath the
opening whence the parts are guided onto cooperating slides 6 wherealong
the singled assembly parts glide by gravity to be transmitted to conveyor
means 7 for orienting the individual assembly parts removed from support
3 through opening 2. The orienting conveyor means may take any desired
form and may be a type of vibratory, elongated, linearly extending conveyor
defining longitudinal gutters holding successive ones of the parts as they
are conveyed linearly therealong by vibration of the conveyor, such as more
fully described and illustrated in U.S. patent No. 4,063,642. As shown,
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the conveyor is mounted on base 38 by means of leaf spring support 39
which is oscillated ~y magnet 40 to vibrate to conveyor in the direction
of its longitudinal extension, such vibratory conveyors being conventional.
If desired, the rotary brush may be omitted and any other suitable singling
means, such as a whirlpool chamber, may be interposed between opening 2 and
the conveyor means to deliver singled assembly parts t~ereto. At the out-
let end of the conveyor (not shown), the singled and oriented assembly
parts are delivered to an assembly station ~not shown).
As shown in FIGURE 1, one of the side walls of receptacle 1
has a removable gate 10 which may be lifted or opened to permit assembly
parts, which may be entangled, to be delivered into the receptacle where
they form the coherent mass which is to be separated into individual parts.
When the mass consists of entangled assembly parts, such as coiled springs,
the continuous and successive lifting and dropping of clusters of the
entangled parts will effectively disentangle them until they are finally
singled by rotary brush 4. If the assembly parts are not actually
entangled but merely cohere under the weight of the mass, such as screws
or bolts to be singled, the lifting and dropping of the clusters by
mechanical means 8, 9 may suffice to single the parts for discharge through
opening 2 without the need of singling and conveying brush 4. While the
opening may be jammed under the weight of the mass in the receptacle, the
continuous and successive relief of the weight of the randomly selected
lifted clusters of assembly parts will enable single parts to become
detached from the coherent mass and to glide singly through opening 2.
The lifting and dropping of the clusters of assembly parts is repeated
until the entire mass has been resolved into individual parts or at least
such small clusters of loosely entangled parts that the parts are
singled by the bristles of rotary brush 4.
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Referring now to the embodiment of FIG~RES 3 and 4, the apparatus
may be used as that of FIGURES 1 and 2 in a three-step method of clustering,
singling and orienting assembly parts from a mass of entangled parts, or
in a two-step method of resolving a mass of entangled parts into predeter-
mined clusters and orienting the clustered parts on a linear conveyor.
The illustrated apparatus is shown to comprise supporting frame 11 including
front wall 12 and rear wall 13 wherebetween rotary drum 14 is supported to
form the receptacle for the coherent mass of assembly parts. As shown, the
support for this mass comprises a plurality of axially extending slats 18
angularly offset relative to each other and constituting the peripheral
wall of drum 14. Slats 18 define a plurality of slot-shaped openings 28
all around the peripheral wall, the slats in this embodiment being
peripherally spaced from each other to define the openings therebetween.
The slats are mounted between disc-shaped end walls 16 and 17 which they
connect to form the receptacle for a coherent mass of assembly parts.
A portion of end wall 16 is constituted by segmental gate 23 hinged to
the wall so that it may be opened to charge the drum with the mass and
locked again when the drum has been charged, at least an upper part of
front wall 12 being removable to enable gate 23 to be opened and the drum
to be charged.
The mechanical means arranged in receptacle drum 14 for
continuously and successively lifting random clusters of assembly parts
out of the coherent mass and away from openings 28 in the peripheral wall
and for dropping the lifted clusters on the support comprises a drive 20-22
for rotating the drum about a generally horizontally extending axis and
axially extending agitator bars 30 associated with slats 18 and projecting
inwardly therefrom towards the axis for entraining random clusters of
assembly parts during rotation of the drum whereby the random clusters are
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continuously and successively lifted and dropped. In the illustrated
embodiment, the drive comprises two pairs of rollers 20, 21 one pair of
rollers being adjacent front wall 12 and the other pair of rollers being
adjacent rear wall 13, and each pair of rollers supporting a respective
end wall of the drum. Removable cover 26 is arranged on the front and
rear walls of supporting frame 11. The cover is removed when it is desired
to remove the drum and replace it by another one. In operation, the drum
is supported by its end walls on the two pairs of rollers 20, 21. One
of the rollers 20 of each pair is an idling roller rotatably supporting
drum 14 while the other rollers 21 of the two pairs of rollers are driven
rollers whose frictional contact with end wall 16 of the drum causes the
drum to be rotated. As shown, rollers 21 of the two pairs of rollers are
keyed to shaft 41 extending parallel to the axis of drum 14, one end of
this shaft being rotatably journaled in rear wall 13 of the supporting
frame and being connected to transmission 22 whose other end is connected
to an output shaft of variable-speed motor 42 mounted on the rear wall.
Adjusting the speed of the tor changes the rotary speed of the drum to
produce desired operating conditions.
In the illustrated embodiment, drum 14 is used for singling
the assembly parts and, for this purpose, openings 28 have a width permitting
only successive single parts to pass therethrough by gravity whereby the
parts are singled in the openings. If the drum were used merely for a
preliminary disentangling operation wherein an entangled mass of parts is
first separated into a multiplicity of small clusters of substantially
uniform numbers of parts which are dropped through openings 28 for
delivery to linear conveyor 7 for orienting the parts, the openings may
have a width permitting the small clusters to fall through.
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Slides or like guide surfaces 27 are mounted below drum 14 to
receive the assemhly parts dropping singly through lowermost openings 28
in the peripheral wall of the drum, the singled parts gliding down slide
27 to linear conveyor 35 which is equivalent to the vibratory conveyor
illustrated in FIGURES 1 and 2 and described ~ereinabove, vibrator 36
being arranged to vibrate the conveyor for conveying the oriented parts
to tray 37.
FIGURE 5 shows a modified rotary drum 15 for use in the appara-
tus of FIGURES 3 and 4 as a substitute for drum 14 and operating in a
functionally equivalent manner. In the modified drum, the support for
the coherent mass of assembly parts comprises a plurality of peripherally
abutting, axially extending slats 19 angularly offset relative to each
other and constituting the peripheral wall of drum 15. Each slat 19
defines slot-shaped openings 29 equivalent to openings 28 all around the
peripheral wall. Hinged gate 24 in one end wall of the drum is equivalent
to gate 23 to enable the drum to be changed and agitator bars 31 associated
with slats 19 are equivalent to bars 30.
In addition, this embodiment further comprises entraining
elements constituted by retaining pins 32 projecting from agitator bars
31 in a direction substantially parallel to the peripheral wall of drum
15 and spaced therefrom, space 33 bounded by slat 19, associated bar 31
and adjacent pin 32 being so dimensioned that, as the drum is rotated in
the direction of arrow 34 to cause agitator bars 31 to sub-divide the mass
of assembly parts into clusters by continuously and successively lifting
selected clusters off support slats 19 and dropping the lifted clusters
thereon until the mass is resolved into clusters and the clusters are
further resolved, and pins 32 assist in relieving the support slats of
the weight of the randomly selected lifted clusters of assembly parts,
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the resolved clusters are singled into individual assembl~ parts as they
drop through the correspondingly dimensioned space 33 singly to pass tllrough
openings 29 at the bottom of space 33.
In all illustrated and hereinabove descrïbed embodiments of
the present invention, a mass of coherent assembly parts, whether originally
entangled or not, is effectively singled into individual parts in a first
operating stage and the singled assembly parts are oriented in a generally
conventional manner in a subsequent, second stage which receives the
singled parts from the first operating stage. In the first stage, the
mass is continuously and successively broken down into constantly shifting
smaller and smaller clusters by relatively simple mechanical means until
the smallest clusters are single to enable individual assembly parts to
be removed to the second stage. The discharge rate of the individual parts
from the first stage may be readily controlled by adjusting the rotary
speed of singling brush 4 in the embodiment of FIGURES 1 and 2 or that
of the drum 14 or 15 in the other embodiments. In all embodiments, the
lifting and dropping of the clusters causes continuously changing
portions of the coherent mass and clusters in the receptacle to rest on
the support and the support surrounding the opening through which the
singled parts are removed continuously and successively. As each cluster
is lifted, the force of gravity causes it to become narrower and longer
while it is widened and pressed together when dropped whereby the clusters
constantly change in shape, the contact faces of adjacent parts in the
clusters constantly change and the contact surfaces of the clusters with
the support also constantly change. All of this is very effec~ive in
first resolving the mass and then further resolving the clusters in the
receptacle even in case of heavy entanglement of the individual assembly
parts in the original mass. Any small clusters not fully resolved into
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individual parts continue to be lifted and dropped until they are singled.
The procedure and the illustrated apparatus described hereinabove is
effective for singling the most complexly shaped assembly parts entangled
in a coherent mass. Such masses are successively loosened by the
successive lifting and dropping of randomly selected clusters thereof
until the parts are entirely disentangled, tfie disentangled parts falling
by gravity through the bottom opening in the receptacle to prevent renewed
entanglement. In the rotary drum, the agitator bars continuously and
successively lift random clusters out of the coherent mass during
rotation of the drum, and the lifted clusters roll or drop back to the bottom
of the drum, the contact faces between clusters, agitator bars and support
constantly shifting and changing while the clusters are simultaneously
agitated. All of this causes single parts finally to be detached from
the coherent mass and to be removed by gravity through bottom openings
in the drum.
The dimensions of the component parts of the apparatus will be
adapted to the mass of parts to be resolved as well as to the size of
the parts, the latter particularly determining the bristle arrangement
of rotary brush 4 and the dimensions of the peripheral openings in rotary
drum 14 or 15.
The method and apparatus of this invention are useful for all
types of assembly parts tending to form coherent masses, including coil
springs, complexly angled spring clamps, pins, bolts, screws and other
metal parts, including reinforcing elements for reinforced concrete.
Where the discharge opening of the receptacle is described
and claimed as having a width permitting only successive single assembly
parts to pass therethrough by gravity whereby the parts are singled in
the opening, this is understood to constitute a cross section of the
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opening which just permits passage of the single parts. Such a cross
section may be smaller than the smallest projected section of a multi-
angled or bent part. A hook is a simple example of such a part and the
opening width for such a hook needs to exceed tfie cross section of one
leg of the hook only by as much as will permit a turning and passage of
the bight portion through the opening after passage of the one leg of the
hook.
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