Abstract
A link of a conveyor chain, connectable to similar links comprising
a main base body with two shoulders, which protrude upward from the
ends of the transverse sides of the main base body and are parallel
to the direction of advancement of the chain. Ends of a pair of first
and second shafts are associated with the pair of shoulders, first
rollers being rotatably associated with the shafts. Second rollers
are associated on the pair of first and second shafts, have a smaller
diameter than the first rollers, and are supported in a loading condition
by first supporting elements, activatable under load and protruding
from the main base body. The link further comprises a slider, supported
by at least one pair of second supporting elements, protruding from
the main base body and has free ends supported on the base body.
Claims
1. A link of a conveyor chain, comprising: connection means for articulated
connection to a similar and adjacent link; a main base body; two shoulders,
which protrude upward from ends of transverse sides of said main base
body and are arranged parallel to a direction of advancement of said
chain; a pair of first and second shafts having ends thereof respectively
associated with said pair of shoulders; first rollers being rotatably
associated with said first and second shafts; second rollers associated
on said pair of first and second shafts, said second rollers having
a smaller diameter than said first rollers; at least one pair of first
supporting elements that support, in a condition in which the link
is loaded, said second rollers, said at least one pair of supporting
elements being activatable when a load passes and protrude from said
main base body and lie on a plane which is transverse with respect
to said pair of first and second shafts; at least one pair of second
supporting elements which protrude from said main base body and lie
on a plane which is parallel to and distinct with respect to the plane
on which said first supporting elements lay; and a slider, which has
an upper surface which lies on a plane which is tangent to adjacent
lateral surfaces of said first and second shafts, said slider being
supported by said at least one pair of second supporting elements,
and having ends thereof which are free and are supported on said main
base body.
2. A link of a conveyor chain, comprising: a main base body; two
shoulders that protrude upward and at lateral ends of transverse
sides of said main base body; said shoulders being arranged parallel
to an advancement direction of the chain; a pair of first and second
shafts; first and second seats formed on said shoulders and being
mutually aligned along an axis which is longitudinal with respect
to said main base body and transverse with respect to the advancement
direction of the chain and with which ends of said pair of first
and second shafts are associated; a plurality of first free rollers
that are rotatably associated with said first and second shafts
and are arranged on a same plane which is parallel to a plane of
arrangement of a surface of said main base body from which said
two shoulders protrude; at least one pair of first supporting elements
that protrudes upward from said main base body, each supporting
element being constituted by two protrusions which are arranged
in pairs along planes that are transverse with respect to said first
and second shafts, each one of said protrusions having, in plan
view, a rectangular shape and being arranged parallel to said pair
of shoulders in a position which is mirror-symmetrical with respect
to a central axis that lies transversely to said main base body.
3. The link of claim 1, wherein each one of said protrusions has,
in a side view, a shape of an inverted right-angled trapezoid, in
which a shorter parallel side is directed upward and a longer parallel
side is rigidly coupled to the main base body, at least one third
seat being formed above each one of said protrusions at the shorter
parallel side, said at least one third seat having a semicircular
cross-section, complementarily shaped lateral surfaces of said second
rollers interacting on said third seats formed on said protrusions
in a loading condition of the link, said second rollers being axially
perforated and having a smaller diameter than said first rollers
and said third seats.
4. The link of claim 3, wherein said first rollers are arranged
along an entire axis of said pair of first and second shafts, except
for regions where said protrusions on which said second rollers
interact protrude from said main base body.
5. The link of claim 4, wherein said second rollers have a smaller
diameter than said third seats and are supported rotatably by said
pair of first and second shafts.
6. The link of claim 4, wherein said second rollers are located
away from said third seats when said pair of first and second shafts
is arranged along a rectilinear configuration, when no load is present
on said first rollers.
7. The link of claim 2, comprising a slider which has an upper
surface arranged on a plane which is tangent to adjacent lateral
surfaces of said first rollers associated with said first and second
shafts.
8. The link of claim 7, comprising second supporting elements constituted
by lugs that are arranged along a distinct plane which lies transversely
to said slider and is also distinct with respect to the planes of
arrangement of said first supporting elements.
9. The link of claim 8, wherein said slider is supported by said
at least one pair of second supporting elements, which protrude
from said main base body and are each constituted by two said lugs
which have a slotted incision or guide on an upper surface thereof,
said incision or guide being adapted to receive and support a complementary
shaped ridge which protrudes downward from said slider.
10. The link of claim 9, wherein each one of said two lugs is arranged
in a respective space that has a different extension than a space
comprised between said pair of first supporting elements, said respective
spaces of arrangement of said lugs being adjacent to said pair of
shoulders.
11. The link of claim 10, wherein said slider has free ends unconnected
to said pair of shoulders.
12. The link of claim 11, comprising end lugs that protrude downward
from the ends of said slider and are shaped like a triangle with
a rounded vertex, said end lugs acting rotatably on complementarily
shaped guides which protrude from said main base body in a region
which is adjacent to said pair of shoulders.
13. The link of claim 10, wherein said first and second shafts
are parallel to each other and to sides of a respective one of said
shoulders, so as to leave a central seat free for said slider.
Description
[0001] The present invention relates to a link of a conveyer chain.
BACKGROUND OF THE INVENTION
[0002] In the provision of industrial systems for bottling liquids
or for packaging goods of various kinds, the design of suitable
systems for moving the products from one processing station to the
next and toward the store is very important.
[0003] In performing the production cycles provided by these systems,
it is often necessary to convey and stop the conveyed products in
chosen positions, so as to be able to perform the various steps
provided by such process, such as for example the filling of bottles,
their closure, or the packaging of products of various kinds, or
the accumulation of packages or containers.
[0004] Known types of conveyor chain, composed of a plurality of
links which are mutually interconnected so as to form a chosen path,
which can comprise straight and curved portions, are currently in
use for moving goods within systems in which the working cycles
provide for conveying or stopping the products in one or more positions.
[0005] One particularly strongly felt need is to allow the products
to stop in the chosen positions without requiring the simultaneous
stopping of the conveyor chain, which would entail high complexity
in production and high costs for its operation.
[0006] For this purpose, it is known to manufacture conveyor chains
which are constituted by interconnecting a plurality of links, each
of which comprises a base body which has a substantially rectangular
plan shape and on the transverse sides of which one or more shafts
are supported which are arranged longitudinally with respect to
the base body and transversely to the direction of advancement of
the products on the chain; a plurality of rollers are associated
with said shafts so that they can rotate freely and constitute the
upper conveyance surface of the chain. A first known type of link
provides, on the transverse sides of the base body, a plurality
of seats which are approximately U-shaped and are open upward for
supporting the one or more shafts, the ends of which are inserted
from above into said seats; a plurality of mutually identical rollers
are associated rotatably on said shafts.
[0007] A second known type of link has, at the transverse sides
of its base body, a plurality of through holes, which are for example
aligned in pairs and within which the ends of the one or more shafts
are inserted and thus supported; a plurality of mutually identical
rollers are associated rotatably with these shafts as well.
[0008] In both of these known embodiments, if the products to be
moved have bulky loads, the shafts, owing to their longitudinal
extension, are made to rest, in one or more of their intermediate
points, on a corresponding number of supports, which protrude upward
from the base body and have a seat for rotatably accommodating a
portion of said shaft.
[0009] The presence of the rollers in said links of the known type
allows to convey the products and to stop them without having to
interrupt the movement of the conveyor chain.
[0010] The moved product can in fact be blocked in the chosen position
by means of a retention barrier without generating an intense friction
force with respect to said chain thanks to the interposition of
the rollers which, by rotating about the shaft that supports them,
reduce drastically the extent of said force; in this manner, the
presence of stationary objects on the chain does not constitute
a hindrance to the advancement of said chain.
[0011] The main drawback that can be observed in these known types
of conveyor chain is that they have high wear of the intermediate
supports, since the shaft that rests on them, if turned by the rollers
that it supports, slides continuously on said intermediate supports,
even in the presence of light loads on the conveyor chain.
[0012] Another drawback of known types of conveyor chain is that
since each shaft rests directly on the corresponding intermediate
support, it is extremely difficult to clean this region of the conveyor
chain, and therefore debris from the outside environment or from
the conveyed products, such as for example dust or splinters caused
by the breakage of glass bottles, can penetrate between the shaft
and the intermediate supports, increasing the drag of the chain
and accelerating its wear; accordingly, long line downtimes are
necessary in order to perform the required cleaning operations.
[0013] Another drawback of said known types of conveyor chain is
that at the intermediate supports there is a considerable discontinuity
in the upper supporting surface, which may give rise to an imperfect
placement of the product on the chain, especially when such product
has a narrow resting base, consequently hindering the correct execution
of the cycle of the system within which said chain is inserted.
[0014] Finally, the use of a large number of rollers entails a
considerable cost increase, since usually each link has at least
three rows of rollers and each chain can be tens of meters long.
SUMMARY OF THE INVENTION
[0015] The aim of the present invention is to solve the above mentioned
problems, eliminating the drawbacks of the cited background art,
by providing a device which allows to achieve low wear of the conveyor
chain, even if it is used to convey material having a certain weight
or if bulky loads are used.
[0016] Within this aim, an object of the invention is to provide
a device which allows quick and easy cleaning, so as to reduce line
downtimes.
[0017] Another object is to provide a device which allows optimum
placement of the conveyed products even if said products have a
narrow resting base.
[0018] Another object is to provide a device which is structurally
simple and has low manufacturing costs.
[0019] This aim and these and other objects, which will become
better apparent hereinafter, are achieved by a link of a conveyor
chain., which comprises means for articulated connection to a similar
and adjacent link and a main base body which comprises two shoulders,
which protrude upward from the ends of the transverse sides of said
main base body and are arranged parallel to the direction of advancement
of said chain, the ends of a pair of first and second shafts being
associated with said pair of shoulders, first rollers being rotatably
associated with said shafts, characterized in that second rollers
are associated on said pair of first and second shafts, have a smaller
diameter than said first rollers, and are supported in a loading
condition by at least one pair of first supporting elements, which
can be activated when a load passes and protrude from said main
base body and lie on the same plane or on a different plane which
is transverse with respect to said pair of first and second shafts,
and in that it comprises a slider, which has an upper surface which
lies on a plane which is approximately tangent to the adjacent lateral
surfaces of said first and second shafts, said slider being supported
by at least one pair of second supporting elements, which protrude
from said main base body and lie on a plane which is parallel and
distinct with respect to the plane of arrangement of said first
supporting elements, the ends of said slider being free and being
supported on said main base body.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Further characteristics and advantages of the invention
will become better apparent from the following detailed description
of a particular but not exclusive embodiment thereof, illustrated
by way of non-limiting example in the accompanying drawings, wherein:
[0021] FIG. 1 is a top perspective view of a link of a chain according
to the invention;
[0022] FIG. 2 is a view, similar to FIG. 1, of the invention, in
which the first and second rollers have been omitted;
[0023] FIG. 3 is a front view of the invention of FIG. 2, with
a single first and second roller inserted;
[0024] FIG. 4 is a top view of the invention;
[0025] FIG. 5 is a view of a detail of the invention;
[0026] FIG. 6 is a view of a detail of the invention with a first
roller and a second roller, shown in partial cross-section, inserted
therein;
[0027] FIGS. 7 and 8 are a perspective view and a detail view of
the slider.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] In the exemplary embodiments that follow, individual characteristics,
given in relation to specific examples, may actually be interchanged
with other different characteristics that exist in other exemplary
embodiments.
[0029] Moreover, it is noted that anything found to be already
known during the patenting process is understood not to be claimed
and to be the subject of a disclaimer.
[0030] With reference to the figures, the reference numeral 1 designates
a link of a conveyor chain according to the invention, which is
constituted by a main base body 2, which is approximately flat and
has an approximately rectangular plan shape.
[0031] Two wings 6 can protrude downward from the base body 2,
in its central region, and are preferably L-shaped and arranged
symmetrically with respect to a central plane of the link 1.
[0032] The link 1 comprises known connection means for articulated
connection to a similar and adjacent link, so as to allow the provision
of a conveyor chain which is constituted by a succession of several
links 1, which are mutually identical and are arranged consecutively
with respect to each other along the advancement direction of said
chain.
[0033] Such connection means for articulated connection are constituted
by a lug 3, which is arranged between the wings 6, protrudes at
the front and centrally from the main base body 2, and has an approximately
trapezoidal plan shape, with its smaller parallel side directed
forward.
[0034] A first bush or a hole 4 is formed on the lug 3, proximate
to its front end 3a, and its axis is arranged transversely with
respect to the advancement direction of the conveyor chain.
[0035] The lug 3 can be accommodated within an approximately complementarily
shaped first seat 5, which is formed centrally at the rear edge
2a of the main base body 2 of an adjacent link 1; the first seat
5 has, in plan view, an approximately rectangular shape, which is
slightly wider than the lug 3, and is open at the rear edge 2a,
so as to allow the insertion of said lug within said seat with a
chosen functional play.
[0036] Two ridges 7 are formed on the wings 6 at said lateral edges
of the first seat 5, and a receptacle 7a is formed therein, has
a preferably circular cross-section and is open toward the inside
of the link 1, in order to support the ends of a transverse pivot,
not shown in the figure, which can be inserted within the through
slot or hole formed in the lug 3 so as to ensure the connection
between two consecutive links 1.
[0037] Said pivot has a smaller diameter than the through slot
or hole; since the first seat 5 further is wider than the lug 3,
relative rotation between two adjacent links 1 on the conveyance
plane is allowed and occurs at curved portions of the conveyor chain.
[0038] The link of conveyor chain 1 according to the invention
can therefore be used both to provide straight conveyance portions
and curved conveyance portions, according to the requirements of
each specific case.
[0039] Two tabs 8 can protrude radially in the opposite direction
from the lower ends of the wings 6, each protruding toward the outside
of the link 1; the tabs 8 can be inserted slidingly within complementarily
shaped seats formed on a guide, which is not shown in the figures,
and which slidingly supports the links 1, so as to contrast forces
which act in the direction for lifting said links and can occur
for example at curved portions of the conveyor chain.
[0040] Two shoulders 10a and 10b protrude upward at the lateral
ends of the transverse sides of the main base body 2 and are arranged
parallel to the advancement direction of the chain; suitable first
10c and second 10d seats are formed thereon and are mutually aligned
along axes which are longitudinal with respect to the main base
body 2 and transverse to the advancement direction of the chain,
with which the ends of two first and second shafts, designated by
the reference numerals 9a and 9b, are rotatably associated, said
shafts being arranged on a same plane which is approximately parallel
to the plane of arrangement of the surface of the main base body
2 from which the two shoulders 10a and 10b protrude.
[0041] Preferably, the first and second shafts 9a and 9b are parallel
to each other and to the sides of the respective shoulder 10a and
10b, so as to leave a clear central seat; a plurality of first axially
perforated rollers 14 are further rotatably associated with each
one of the first and second shafts 9a and 9b, in particular with
the shafts inserted therethrough.
[0042] At least two first supporting elements protrude upward from
the main base body 2, each element being constituted by two protrusions
12a, 12b and 12c, 12d, which are arranged in pairs on the same plane
or on a separate plane which lies transversely to said pair of first
and second shafts.
[0043] Each protrusion 12a, 12b, 12c, 12d has, in plan view, an
approximately rectangular shape, is parallel to the shoulders 10a
and 10b, and is advantageously arranged in a mirror-symmetrical
manner with respect to the central axis which lies transversely
to the main base body 2.
[0044] Each protrusion 12a, 12b, 12c, 12d, in a side view, is shaped
approximately like an inverted right-angled trapezoid, in which
the shorter parallel side is arranged upward and the longer parallel
side is rigidly coupled to the main base body.
[0045] Above each protrusion 12a, 12b, 12c, 12d there are provided,
at the shorter parallel side, one or more third seats 13, which
are approximately semicircular in cross-section and on which the
complementarily shaped lateral surfaces of a second roller 15 interact
in the loading condition for said link, said roller being perforated
axially and having a diameter which is smaller than the diameter
of the first rollers 14 and of the third seats 13.
[0046] The first rollers 14 are arranged along the entire axis
of the pair of first and second shafts 9a and 9b, except for the
regions where the two protrusions 12a, 12b and 12c, 12d protrude
from the main base body 2, and second rollers 15 engage in such
protrusions; the second rollers 15 advantageously have a rolling
surface which is centrally concave and is arranged between two flat
lateral shoulders thereof. Since the second rollers 15 have a smaller
diameter than the third seats 13 and are supported rotatably by
the pair of first and second shafts 9a and 9b, they do not rest
on said third seats when said pair of lateral shafts is arranged
in a straight configuration, for example when no load is present
on the first rollers 14. The link further comprises a slider 9c,
which has an upper surface 60 which lies on a plane which is approximately
tangent to the adjacent lateral surfaces of the first rollers associated
with said first and second shafts. The slider 9c is interposed advantageously
between said first and second shafts 9a, 9b and is supported by
at least one pair of second supporting elements, which protrude
from the main base body 2 and are each constituted by two lugs 51a
and 51b, which have a slotted incision or guide in the upper surface
which is adapted to receive and support a complementarily shaped
ridge 70, which protrudes downward from said slider 9c. The two
lugs 51a and 51b are arranged along a distinct plane, which is transverse
with respect to the slider 9c and is also distinct with respect
to the plane of arrangement of said first supporting elements 12a,
12b, 12c, 12d.
[0047] Advantageously, said two lugs are each arranged in the space
that is not comprised between said pair of first supporting elements
12a, 12b, 12c, 12d and are therefore adjacent to said pair of shoulders.
[0048] The slider 9c further has its ends 52a and 52b free and
not connected to the two shoulders 10a and 10b.
[0049] End lugs 61 protrude downward from the ends 52a and 52b
and are approximately shaped like a triangle with a rounded vertex
which acts rotatably on complementarily shaped guides 53a and 53b,
which protrude from the main base body 2 in a region which is adjacent
to the pair of shoulders 10a and 10b.
[0050] The operation of the link of conveyor chain according to
the invention entails that if no load or a light load, constituted
for example by an empty bottle, is present thereon, the pair of
first and second shafts 9a and 9b has an approximately straight
non-deformed configuration, so that the second rollers 15 are raised
with respect to the respective facing third seat 13.
[0051] In this operating condition, the pair of first and second
shafts 9a and 9b is rotatably associated only with the shoulders
10a and 10b, while the first and second rollers 14 and 15 are free
to rotate in order to allow relative sliding of the product supported
thereby with respect to the link 1, for example if said product
supported thereby is locked in a chosen position by a retention
barrier; low drag opposing the advancement of the conveyor chain
is thus generated.
[0052] If the load conveyed by the link 1 is considerably heavy,
the two first and second shafts 9a and 9b are arranged according
to a deformed configuration; if the weight of said load exceeds
a preset value, which can be defined for example analytically or
experimentally, the lateral surface of the second rollers 15 makes
contact with the corresponding surface of the third seat 13, so
as to constitute a supporting point for the two first and second
shafts.
[0053] In this condition, the second rollers 15 do not rotate freely,
since they are locked by the friction between its lateral surface
and the surface of the third seat 13; the presence of the second
rollers 15, however, avoids the wear of the protrusions 12a, 12b,
12c and 12d, since there is no direct contact with the two first
and second shafts, which rotate, and the surface of the third seat
13, which is fixed.
[0054] Further, the second rollers 15 rest on the surface of the
third seat 13, remaining locked in their rotation, only if the weight
of the conveyed load exceeds a preset value; wear processes are
thus slowed further, since if a lightweight load is conveyed, the
second rollers 15 are not in contact with the protrusions and therefore
can rotate freely, no action being applied to the protrusions.
[0055] If debris, constituted for example by glass splinters caused
by the breakage of conveyed bottles or by dirt from the surrounding
environment, occurs on the link 1, it is further very easy to clean
said link also at the central support.
[0056] This applies also to the slider 9c at the ends 52a and 52b,
which are not supported by the two shoulders 10a and 10b.
[0057] Further, the presence of the second rollers 15 allows to
obtain good uniformity of the upper loading surface, since the difference
between the outside diameters of the first and second rollers can
be very small; good positioning is therefore insured even in the
case of products which have a narrow resting base.
[0058] The presence of the surface 60 of the slider further allows
to support bulky loads in an optimum manner.
[0059] It has thus been found that the invention has achieved the
intended aim and objects, an invention having been provided which
allows to ensure low wear thereof during operation as well as quick
and easy cleaning thereof, so as to require reduced line downtimes.
[0060] Finally, the invention allows optimum positioning of the
conveyed products, even if said products have a narrow resting base
or are constituted by bulky loads.
[0061] Of course, the materials used, as well as the dimensions
that constitute the individual components of the invention, may
of course be more pertinent according to specific requirements.
[0062] The various means for performing certain different functions
need not certainly coexist only in the illustrated embodiment, but
may be present per se in many embodiments, including ones which
are not illustrated.
[0063] The characteristics indicated as advantageous, convenient
or the like may also be omitted or be replaced with equivalents.
[0064] The disclosures in Italian Patent Application No. TV2005A000120
from which this application claims priority are incorporated herein
by reference.
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