[0001] The present invention relates to a retention device for a conveyor for safety cages
for tops of bottles for sparkling drinks having the characteristics defined in the
preamble of Claim 1.
[0002] With reference to Figures 1a, 1b and 2a, 2b a safety cage 2 is generally constituted
by a body 3 and a strap 4, each formed by a single shaped length of metal wire. The
body 3 is constituted by an annular element 30, designed to constitute a rest for
a cap 5 made of metal plate, designed to co-operate with a top surface of the top,
and by four legs 3b extending from the annular element 3a in positions such that they
are set at the same angular distance apart from one another, slightly diverging with
respect to an axis of extension X of the cage 2, and are provided with respective
end eyelets 3c. The strap 4 is mounted through the eyelets 3c and is designed to enable,
in use, gripping of the cage around the neck of the bottle.
[0003] The cages are produced in automatic machines comprising a plurality of processing
stations through which the semifinished products and the finished cages are fed. In
order to convey the semifinished products and the finished cages from one station
to another conveyors of the carousel type are generally provided.
[0004] The known conveyors are provided with housing elements for the semifinished products
and the cages and with devices for clamping the products themselves in the housing
elements during transfer between the various processing stations.
[0005] A type of clamping device is, for example, known from the patent No.
IT 1072710. Said device comprises a clamping pin that can be displaced vertically, which is
mounted on each housing element. Said solution entails a relatively large number of
items, which renders the structure of the housing element itself complex. In addition,
it requires the use of mechanical means set along the path of rotation to activate
and deactivate clamping in the positions required.
[0006] Another type of clamping device is, for example, known from the patent No.
IT 1285348. Said device comprises a pair of rails extending along part of the path of rotation,
which are designed to co-operate slidably with the annular element or with the cap
of the cages. Said solution entails a sliding on the body or on the cap of the cage,
which can lead to furrows on the material, and hence an undesirable alteration of
its characteristics. In addition, it may involve a complex adjustment in order to
achieve a proper positioning of the rails.
[0007] The purpose of the present invention is to provide a retention device that will eliminate
the aforesaid drawbacks regarding the known art.
[0008] The present invention achieves the aforesaid purpose thanks to a retention device
for a conveyor for safety cages for tops of bottles for sparkling drinks having the
characteristics recalled in Claim 1.
[0009] A device of the type referred to above is consequently able to withhold the semifinished
product or the finished cage throughout the path of the conveyor, without having to
resort to a mechanical clamping of the piece, thus rendering process of formation
of the cages much more precise and simplifying the steps of loading and unloading
of the products.
[0010] In addition, no type of mechanical clamping is present that might damage, even slightly,
the body of the cages as they are turning.
[0011] Advantageous embodiments of the invention are recalled in the dependent claims.
[0012] The invention will now be described, purely by way of non-limiting example, with
reference to the attached plates of drawings, in which:
Figures 1a and 1b are, respectively, a side elevation and a plan view of the body
of a traditional safety cage;
Figures 2a and 2b are, respectively, a side elevation and a plan view of the body
of a traditional safety cage;
Figure 3 represents a plan view of a conveyor for safety cages provided with retention
devices according to the invention;
Figure 4 is a cross-sectional view of the conveyor of Figure 3; and
Figures 5 to 8 represent, respectively, a front view, a side view, a rear view, and
a plan view of a retention device for safety cages according to the invention.
[0013] Figures 3 and 4 represent a conveyor 10 for safety cages for tops of bottles for
sparkling drinks. The conveyor 1 is designed to form part of an automatic machine
for the production of cages (not illustrated), which in general comprises a plurality
of processing stations, along which the semifinished products and the finished cages
are fed at regular intervals by the conveyor 1. The conveyor typically comprises also
loading and unloading devices for feeding the bodies 3 of the cages to the conveyor
1 and for taking the finished cages 2 off said conveyor 1, said devices not being
illustrated in so far as they are not essential for the purposes of the invention.
A complete system for moving the semifinished products and the cages is described,
for example, in the
Italian patent No. IT 1285348.
[0014] The conveyor 10 is of a type in itself traditional, and comprises a circular table
20, which is mounted on a machine 40 so that it can turn about an axis A. The machine
40, which is of a conventional type, is designed to cause an intermittent movement
of rotation of the circular table 20. A machine of this type is, for example, an intermittent
rotary table with globoidal cam, which converts a uniform rotary motion at input,
transmitted to the machine by a drive shaft (not illustrated), into an intermittent
rotary motion about the axis A at output.
[0015] The type of mechanism that produces motion of the rotary table 20 is not, however,
essential for the purposes of the invention, and could be of any type known to the
person skilled in the branch.
[0016] The conveyor 1 further comprises a plurality of retention devices 50, which are designed
to support and withhold the safety cages and are mounted along the perimeter of the
table 20.
[0017] A retention device 50 according to the invention is illustrated in greater detail
in Figures 5 to 8 and basically comprises a plate-like body 51 and a base 52, which
extends form one end of the plate-like body 51, for fixing to the table 20. In order
to enable fixing of the retention device 50 to the table 20, made in the base 52 is
a hole 53 for a fixing screw (not illustrated). Made in the plate-like body is a through
opening 54, having axis of symmetry B, which is in use set radially with respect to
the table 20. The opening 54 extends from a front face 51a towards a rear face 51b
of the plate-like body 51. In use, the rear face 51b of the plate-like body 51 faces,
in a radially internal direction, the axis A of the table 20 (Figures 3 and 4). The
opening 54 defines a receptacle for housing the body 3 of the safety cage. Made on
an internal surface of the opening 54 are four internal grooves 55, which are set
at the same angular distance apart from one another and converge towards the rear
face 51b of the body 51. The grooves 55 extend along mutually orthogonal planes, passing
through the axis B and inclined by 45° with respect to a horizontal plane passing
through the axis itself. Moreover made on the front face 51a of the plate-like body
51 is a collar portion 56, extending in a direction perpendicular to said face 51a.
In addition, made in the front face 51a of the plate-like body and in the collar portion
56 are four notches 57, each of which is set angularly aligned to a respective groove
of the four internal grooves 55 of the opening 54. The collar portion 56 is moreover
interrupted in two diametrally opposite positions with respect to the vertical direction.
[0018] According to the invention, mounted on the rear face 51b of the plate-like body 51
are four permanent magnets 60, each of which is set angularly aligned to one respective
groove of the four internal grooves 55 of the opening 54. Made in the body of each
magnet is a hole 61 for a screw (not illustrated), designed to fix the magnet 60 to
the plate-like body 51. The magnets 60 are designed to exert a contactless force on
the body 3 of the cage in such a way as to cause it to rest upon the internal surface
of the grooves 55.
[0019] In use, the conveyor 1 conventionally envisages a loading step, in which a cage body
3 is introduced radially inwards into the respective retention device 50 at a loading
station (not illustrated). The product is housed inside the device 50 with its own
axis X coinciding with the axis B of the device itself, and with the legs 3b of the
cage engaged inside the respective grooves 57. Consequently, the product is blocked
in an angular direction, and is axially constrained unidirectionally in so far as
it cannot advance any further on account of the fact that the legs 3b are resting
against the internal surface of the grooves 55 of the device 50, and that the eyelets
3c are resting in the notches 57, which define, inside the collar portion 54, seats
57a for said eyelets. The annular element 3a of the cage projects axially with respect
to the rear face 51b of the plate-like body 51 towards the axis A (see Figure 4) so
that each magnet 60 is able to attract towards it a protruding portion of the respective
leg 3b of the cage, maintaining the legs 3b resting against the internal surface of
the grooves 55 even when the retention device is transferred outside the loading station.
[0020] The process of fabrication of the cages then conventionally envisages a step of insertion
of the strap and cap, so that set along the path of the conveyor are insertion stations
(not illustrated), to which the body 3 of the cage, withheld by the respective retention
device 50, is subsequently fed so as to obtain finally the finished cage.
[0021] Finally, there is an unloading step, in which the finished cage is conventionally
taken off the respective retention device in an unloading station (not illustrated).
[0022] Conveyance of the products through the various stations hence occurs through a rotation
at regular intervals of the rotary table 20. Said rotation of course generates a centrifugal
force, indicated by the arrow Fx in Figure 4. The magnets 60 are sized in such a way
as to exert a retaining force on the legs 3b of the cage, which is able to overcome
said centrifugal force.
[0023] As may be appreciated, the magnets 60 enable a retaining function to be exerted on
the bodies of the cages also during the steps of loading, unloading, and processing,
unlike the conventional mechanical retention devices described in the introductory
part of the description. In fact, in the conventional devices described above, the
mechanical parts having the function of clamping the cages in the various processing
stations had to be deactivated, or else were even absent, in order to prevent any
interference with the processing devices present in said stations.
[0024] Instead, in the case of the device according to the invention, the magnets are set
in such a way as not to collide with other mechanisms, thus rendering processing much
more precise and simplifying the steps of loading and unloading of the products.
[0025] Another advantage lies in the fact that there is no type of mechanical clamping that
might damage, even just slightly, the body 3 of the cages as they are turning, in
so far as the magnets 60 are not in contact with said body.
[0026] Of course, without prejudice to the principle of the invention, extensive variations
may be made to what is described and illustrated herein, without thereby departing
from the sphere of protection of the invention itself.
1. A retention device (50) for a conveyor (10) for safety cages for tops of bottles for
sparkling drinks comprising a device body (51) designed to be fixed to a rotary table
(20) of said conveyor, made in which is a receptacle (54) for housing the body (3)
of a safety cage, said device being characterized in that it further comprises contactless-acting means (60) mounted on said device body, which
are designed to exert a contactless force on said cage body in such a way as to cause
it to rest upon the resting surface (55) of said receptacle.
2. The device according to Claim 1, in which said contactless-acting means are constituted
by magnetic means.
3. The device according to Claim 2, in which said magnetic means are constituted by one
or more permanent magnets.
4. The device according to Claim 3, in which said receptacle is defined by a through
opening (54) made in the device body (51), which extends from a first face (51a) of
the device body towards a second face (51b) of the device body.
5. The device according to Claim 4, in which said resting surface of the receptacle is
defined by four internal grooves (55) made on the internal surface of the receptacle,
set at the same angular distance from one another and converging towards the second
face (51b) of the device body.
6. The device according to Claim 5, in which moreover made on the first face (41a) of
the device body is a collar portion (56) extending perpendicular from said first face
(51a), in said first face (51a) and in the collar portion (56) there being made four
notches (57), each of which is set angularly aligned to a respective groove of the
four internal grooves (55) of the receptacle (54).
7. The device according to Claim 3 in combination with Claim 5 or Claim 6, in which said
permanent magnets number four and are mounted on the second face (51b) of the device
body, each of the magnets being set angularly aligned to a respective groove of the
four internal grooves (55) of the receptacle (54).
8. A conveyor (10) for safety cages for tops of bottles for sparkling drinks, comprising
a plurality of retention devices (50) according to any one of the preceding claims.