U.S. patent number 3,574,386 [Application Number 04/737,557] was granted by the patent office on 1971-04-13 for grasping fingers.
Invention is credited to James D. Frost.
United States Patent |
3,574,386 |
Frost |
April 13, 1971 |
GRASPING FINGERS
Abstract
Improved inflatable grasping or picking fingers forming
article-grasping elements for handling various articles, such as in
the picking of fruit from trees or transferring fruit or food from
one conveyor to another or depositing the same within containers,
each finger having a rigid support or "bone" and tie means for
limiting the radial distention of the finger from the support when
it is inflated. In one form of the invention, the outer covering of
the finger is connected to the central support by flexible threads
or strands. In another form, the outer covering is connected to the
central support by a web of sheet fabric disposed transversely or
longitudinally of the support. In still another form, the outer
contour of the finger is defined by the free portions of a
plurality of sections or chambers of flexible material. In one form
the sections are partitioned longitudinally of the central support
with provision for individually selectively inflating the sections.
In another form, the sections are substantially coextensive with
and disposed circumferentially about the central support with the
longitudinal axes of the sections generally parallel thereto,
including means for selectively inflating any or all of the
sections; whereby some of the articles being grasped may be dropped
while a holding grip is retained on others. In still another form,
the sections are partitioned both longitudinally and
circumferentially of the central support.
Inventors: |
Frost; James D. (Porterville,
CA) |
Family
ID: |
24964381 |
Appl.
No.: |
04/737,557 |
Filed: |
June 17, 1968 |
Current U.S.
Class: |
294/87.1; 294/92;
294/119.3; 294/98.1 |
Current CPC
Class: |
A01D
46/24 (20130101); B25J 15/0023 (20130101) |
Current International
Class: |
B25J
15/00 (20060101); A01D 46/00 (20060101); A01D
46/24 (20060101); B66c 001/10 () |
Field of
Search: |
;294/67,87,87 (A)/
;294/93,99,92 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Hornsby; Harvey C.
Claims
I claim:
1. A grasping finger for use in apparatus adapted to grasp discrete
articles disposed between a plurality of such elements, comprising
an elongated substantially rigid support, a distendable elongated
envelope having an outer grasping portion circumscribing said
support and of a length substantially coextensive therewith, and
tie means within the envelope interconnecting said portion and said
support for limiting the extent to which said envelope can be
radially displaced from said support.
2. The finger of claim 1 wherein said tie means comprises flexible
strands of substantially fixed length.
3. The finger of claim 1 wherein said tie means comprises a sheet
of flexible material.
4. The finger of claim 3 wherein said sheet of flexible material is
disposed transversely of said support.
5. The finger of claim 1 wherein said tie means comprises sheets of
flexible material disposed in longitudinally spaced relation on
said support and extending transversely thereof.
6. The finger of claim 5 wherein said transversely extending sheets
of flexible material have apertures therein.
7. The finger of claim 1 wherein one end of said envelope is
provided with protective means.
8. An article-grasping device comprising a plurality of elongated
radially distendable fingers between which relatively fragile
articles can be grasped, each of said fingers having an elongated
substantially rigid support; an envelope of somewhat flexible
material mounted on the support; and tie means within said envelope
interconnecting the envelope and said support for limiting the
extent to which the fingers are deformed incident to article
engagement to insure dependably firm but gently gripping of such
articles while precluding engagement of the articles against said
rigid supports.
9. The device of claim 8 in which said tie means comprises a sheet
of flexible material of substantially fixed radial dimensions.
10. The device of claim 9 in which said sheet of flexible material
is disposed transversely of said support.
11. The device of claim 8 in which said tie means comprises a
plurality of flexible sheets disposed in longitudinally spaced
relation along said support and being transversely extended
therefrom a predetermined substantially fixed radial dimension.
12. The device of claim 11 including a plurality of per apertures
in said sheets.
13. An article-grasping device comprising a plurality of elongated
radially distendable fingers between which relatively fragile
articles can be grasped, each of said fingers having an elongated
substantially rigid support; means mounting the supports in
substantially fixed spaced relation; inflatable envelopes of
flexible material individually mounted on the supports having
external article engaging surfaces; means for inflating said
envelopes; and flexible tie means within said envelopes
interconnecting their respective envelopes and their supports for
limiting the extent to which the fingers are deformable at and
adjacent to the positions of connection of the tie means thereto to
preclude excessive radial displacement of the envelopes relative to
their respective supports to insure optimum cushioning of the
articles being grasped.
Description
BACKGROUND OF INVENTION
This invention relates to apparatus for handling foods and fruits
of the type employed for transferring fruit from one location to
another such as picking fruit from trees, or transferring fruit
from one conveyor to another or depositing the fruit within
containers, cartons, crates, or boxes and the like, and more
particularly to improvements in inflatable picking fingers which
grasp or seize the fruit with a sufficient force to achieve the
transferring, yet the grasping force is not so great as to bruise
or otherwise damage the fruit or food so as to render the same
unsightly or inedible.
The general type of article-handling apparatus referred to is shown
and described in U.S. Pat. No. 3,347,587 in which the article is
grasped by a plurality of inflatable fingers including essentially
a central support or "bone" and a flexible outer covering divided
into sections by means of spaced circumscribing collars or bands,
each section of finger being inflated or distended by means of
pressurized air passing through the central support and discharged
through suitably spaced ports which are in communication with the
finger sections. While the apparatus of the aforementioned patent
has been very effective in the handling of food and fruit, further
dependability and standardization of operations is desired,
particularly with respect to predetermining the maximum distention
thereof.
SUMMARY OF INVENTION
It is therefore an object of the present invention to provide
improved grasping fingers in an article-handling apparatus.
Another object is to provide improved grasping fingers in an
article-handling apparatus which fingers are inflatable and distend
radially with inflation but are inherently limited in the amount of
such radial distention.
A further object is to provide improved fingers of the character
referred to in which each finger is made up of flexible sections in
communication with each other and each finger is inflatable for
progressively radially distending the finger from the base to the
distal end thereof.
Still another object is to provide an improved grasping finger in
an article-handling apparatus which is sectionalized longitudinally
of the central support of the finger and includes inflation
mechanisms for radially distending the sections for the grasping of
articles.
A still further object is to provide an improved grasping or
picking finger which is made up of a plurality of elongated
sections circumferentially disposed about a central support having
inflation means for selectively inflating one or all of the
longitudinal sections for the purpose of dropping out some articles
while retaining others.
An additional object is to provide an improved grasping finger
which is made up of sections partitioned both longitudinally and
circumferentially of the central support for varied
application.
These and other objects and advantages are achieved by an improved
grasping finger having an elongated, substantially rigid central
support and an outer covering of suitable laminated flexible
material surrounding the central support and inflatable for causing
the covering to distend outwardly from the central support and is
connected thereto in a manner limiting such outward distention. In
one instance, the distention is limited by means of flexible
threads or strands and in another by webs of material disposed in
planes transversely of the longitudinal axis of the central support
or in planes intersecting generally at or in the vicinity of the
longitudinal axis of the central support. In the case of the
former, the finger is divided up into a plurality of sections
disposed along the central support with inflating mechanisms for
progressively or selectively individually inflating the sections.
In the case of the latter, the finger is made up of a plurality of
longitudinally extending sections disposed circumferentially about
the central support which is provided with air passageways for
selectively extending any one or all of the longitudinal sections.
In still another form of the finger, both features are
combined.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a fragmentary longitudinal section illustrating a finger
of the present invention in inflated condition.
FIG. 2 is a fragmentary cross section illustrating a plurality of
fingers of the present invention grasping an article therebetween
and showing the means for limiting distention of the fingers.
FIG. 3 is a cross section on a larger scale of a finger of the
present invention showing a different manner for limiting the
distention of the finger.
FIG. 4 is a fragmentary longitudinal sectional perspective view of
a finger of the present invention showing still another manner of
limiting the distention thereof.
FIG. 5 is a fragmentary longitudinal section of another finger of
the present invention in which the finger is partitioned into
sections disposed along the central support thereof.
FIG. 6 is a view somewhat similar to FIG. 5 but illustrating the
manner of selectively individually inflating the sections of the
finger.
FIG. 7 is a fragmentary perspective view of a form of the finger of
the present invention in which the finger is defined by a plurality
of elongated chambers extending substantially coextensively with
the central support of the finger and disposed circumferentially
therearound.
FIG. 8, 9 and 10 are cross sections illustrating various forms of
the central support of the finger and illustrating the manner of
selectively individually inflating each of the sections or
chambers.
FIg. 11 is a perspective view of a finger in which the elongated
air chambers are partitioned into sections along the central
support, the sections of one chamber being staggered with respect
to the sections of adjacent chambers.
DESCRIPTION OF EMBODIMENTS
Referring to Fig. 1, there is illustrated an improved picking
finger embodying the principles of the present invention designated
generally by reference numeral 20. Finger 20 includes a
substantially rigid central support or "bone" in the form of a
tubular support or tube 22 and disposed thereabout is an envelope
24, preferably of fabric and elastomer materials laminated as
described in the aforementioned U.S. Pat. No. 3,347,587. Tube 22
extends through a sleeve 26 supported in base plates 28 and 30.
Tube 22 may be mounted for rotation in the sleeve 26, rotation
being imparted thereto by a collar 32 fixed to the support 22 and
having an actuating lever 34. Adjacent plate 28 is a band or collar
36 which secures one end of the envelope 24 to the tubular support
22.
Tube 22 is disposed substantially perpendicularly to plates 28 and
30 and is provided with a plurality of apertures or ports 38 which
communicate the interior of the tube with the interior of the
finger envelope 24, the distal end of the tube being closed. The
other end of the tube 22 is adapted to be connected to a source of
pressurized air, not shown. Thus, the introduction of air into the
envelope 24 through the ports 38 inflates and distends the same to
engage with an article 40.
Inviting attention also to FIg. 2, it will be noted that the
envelope 24 is connected or tied to the central tubular support 22
by tie means in the form of generally radially extending strands or
threads 42 of a material which is flexible but has a limited
elastic modulus for limiting the extent to which the envelope is
distended upon inflation of the finger. The distal ends of the
threads 42 are suitably secured to the envelope 24 as by bonding or
the like and the inner ends of the threads are conveniently
connected to a plurality of bands or collars 44 circumscribing the
tube 22 at longitudinally spaced points therealong. As seen in FIG.
2, upon inflation of the fingers 20 with an article 40 disposed
therebetween, the finger envelopes 24 are distended, such
distention being limited by the threads or strands 42 but
deformation of the envelopes and threads is permitted to grasp and
retain the article 40.
FIG. 3 illustrates another manner of interconnecting the central
tube 22 and the finger envelope 24 in which a plurality of threads
or strands 42' extend transversely of the tubular support and have
the midpoints 44' thereof bonded or otherwise secured to the tube,
the distal ends of the threads being bonded or otherwise secured to
the finger envelope 24.
As shown in FIG. 4, there is illustrated another form of a grasping
finger in accordance with the present invention designated
generally by reference numeral 20a which is essentially the same as
finger 20 except that the threads or strands 42 are replaced with a
web or disc of sheet material 46 which is flexible but has limited
radial elasticity for limiting distention of the envelope 24 upon
inflation of the finger. Discs 46 serve, in effect, to divide the
envelope into sections longitudinally of the support 22 and the
disc at the base of the finger may be reinforced by a flanged
collar 36'. The interior discs may be apertured, as at 48, to
provide communication between the sections. If desired, the number
of ports 38 in the tube 22 may be limited in order that the
sections of the finger envelope may be progressively inflated in
either direction from the point of introduction of air into a
selected section. FIG. 4 also illustrates a protective device for
the picking finger which may be a cap 50 of flexible but durable
material, such as plastic, having the general shape of a surface of
a cone with a rounded apex.
FIG. 5 illustrates a finger 20b which is essentially like finger
20a but has a finger envelope which is defined by a plurality of
members or sections 24b each having an inwardly directed annulus
forming an end wall 46' at each end thereof provided with an
annular flange or collar 52 adapted to circumscribe tube 22 and be
bonded or otherwise secured thereto. Members 24b may be mounted on
the tube 22 with adjacent end walls 46' in contact and bonded to
each other, the contiguous end walls being apertured as at 48' to
provide communication between the interiors of the members 24b or
the contiguous end walls 46' may be left unapertured and unbonded
to each other and each member 24b may be individually inflated
through a port 38 in tube 22 in communication therewith. Flanged
collars 36' serve to reinforce or back up the end walls 46' of the
end section members 24b.
FIG. 6 illustrates a finger 20c the contour of which is defined by
a plurality of envelope sections 24c individually secured to a
central support or tube 22c and individually inflatable through an
air conduit individual thereto. Thus, the envelope section 24c at
the base of the finger 20c is adapted to be inflated through an air
conduit 38a, the next envelope section through an air conduit 38b,
and so on, air conduit 38n serving to inflate the distal envelope
section 24c. With such an arrangement, the envelope sections 24c
may be progressively distended by inflation or only selected
envelope sections may be inflated, as desired. For example, where
fingers 20c are part of an apparatus operating to pick up a layer
of articles and deposit them in a packing case, only the distal
envelope sections at the ends of the tubes 22c need be inflated,
resulting in a more rapid inflation and deflation with a consequent
saving in the amount of air required. Also, where some sections are
exposed to greater wear and require replacement, only the worn
sections need to be replaced rather than the whole envelope of the
finger. Finger 20c may be provided with a collar 36' to reinforce
section 24c at the base thereof and a protective cap 50' at its
distal end.
Additionally, with the fingers 20c operated to inflate all the
envelope sections 24c thereof, thereby grasping several layers of
articles, the envelope sections may be deflated layer by layer in
order that the first layer may be placed in one container, the next
layer in another container, and so on.
Another form of picking finger 20d in accordance with the present
invention is illustrated in FIG. 7. Finger 20d includes a central
support or tube 22d suitably supported in base plates 28' and 30' .
Disposed about the support 22d are envelope sections 24d of
elongated form which are substantially coextensive with the support
and held thereon by a retaining collar 36'. It will be noted that
each envelope section 24d has a substantially sectorlike cross
section with inwardly directed sheet portions 54 interconnected by
a web portion 56, portions 54 being substantially disposed in
radially extending planes intersecting generally at the central
longitudinal axis of the support 22d, the web portion 56 being
suitably bonded or otherwise secured to the support 22d and
suitably apertured or ported as at 38a to provide communication
between the interior of the envelope section 24d and the air
passageway through the support 22d. In lieu of such communication,
apertures 38a and ports in the support 22d may be omitted and each
of the envelope sections 24d individually inflated by individual
conduits 58.
Alternatively, as seen in FIG. 8, each of the envelope sections 24d
can be individually inflated by employing partitions 60 inside the
central tubular support 22d to provide individual air passageways
in communication with apertures or ports 38a individual to the
sections. The same effect can be obtained employing concentric
tubes 60t as shown in FIG. 9, the central tubular support 22c in
this case being cylindrical. However, it is to be understood that
the central support may be of any desired cross section suitably
partitioned to provide the number of air passageways required or
desired. For example, the central tubular support can be square, or
of hexagonal cross section 22e, as shown in FIG. 10, and have the
interior thereof subdivided by partitions 60p with each of the
sides of the hexagon having an envelope section 24e secured
thereto. Thus, the central supports shown are exemplary only and
are not limited to such forms since obviously the cross section of
a central support can be polygonal or arcuate, circular or
noncircular, as necessary or desirable.
FIG. 11 illustrates a form of picking finger 20f in accordance with
the present invention which is a composite of the forms of fingers
illustrated in FIGS. 6 and 7. Viewing FIG. 11, it will be noted
that the contour of the finger is defined by a plurality of
envelope sections 24f which are placed in end-to-end relation on
central support or tube 22f to give the effect of an elongated
envelope section similar to envelope section 24d of FIG. 7 which is
substantially coextensive with the tube. A plurality of such
sections are disposed about the tube 22f in staggered relationship
to define the finger contour. The interior of tube 22f may be
suitably partitioned to provide a sufficient number of air
passageways for individually and selectively inflating the several
sections as desired.
The finger of FIG. 6 is shown as having a protective cap 50'. It
will be appreciated that the fingers of FIGS. 7--11 can have such a
cap as well.
OPERATION
The operation of the grasping or picking fingers of the present
invention is believed to be clearly apparent and is briefly
summarized at this point. Turning to FIGS. 1 and 2, fingers 20 in
deflated condition thereof are inserted among articles to be picked
or grasped and the fingers are inflated to distend the envelopes 24
thereof, such distention being limited by the length of the threads
or strands 42. This prevents translation of the axes of the
envelopes and in effect provides a reaction for the exertion of
pressure on that part of the envelope deformed by engagement with
an article, whereby the article is grasped with a firm gentle grip
which is releasable upon deflation of the fingers. In the forms of
the fingers which are sectioned, by selective inflation and
deflation, articles may be selectively grasped, after which some
may have the grip thereon released for dropping the same at one
point or in a layer, while retaining the grip on the remaining
articles for further handling.
There have, thus, been provided novel picking fingers of improved
form which may be variously formed to provide varied application
thereof for different handling of articles.
Although the invention has been herein shown and described in what
are conceived to be the most practical and preferred embodiments,
it is recognized that departures may be made therefrom within the
scope of the invention which is not to be limited to the details
disclosed herein but is to be accorded the full scope of the claims
so as to embrace any and all equivalent devices and apparatus.
* * * * *