U.S. patent application number 15/653135 was filed with the patent office on 2018-01-25 for device for filling inhomogeneous products.
The applicant listed for this patent is WEIGHTPACK S.R.L.. Invention is credited to Vanni Zacche'.
Application Number | 20180022480 15/653135 |
Document ID | / |
Family ID | 57737864 |
Filed Date | 2018-01-25 |
United States Patent
Application |
20180022480 |
Kind Code |
A1 |
Zacche'; Vanni |
January 25, 2018 |
DEVICE FOR FILLING INHOMOGENEOUS PRODUCTS
Abstract
A filling device for inhomogeneous products or products which
have solid or semisolid elements of variable size and compactness
in suspensions. In particular, the a filling device for filling
machines is provided comprising a hollow body in which a delivery
member is movably inserted, wherein the hollow body comprises a
lower portion comprising a delivery duct which ends with a delivery
opening, said lower portion being intercepted by a cone-shaped
rotating shutter, comprising a major base, a minor base and a
through hole which is aligned with the delivery duct when the
filling device delivers a product, characterized in that the minor
base of the rotating shutter is associated with a drawing system,
which applies a constant and predetermined drawing force on said
minor base. The valve described in the invention can be used in net
weight filling machines.
Inventors: |
Zacche'; Vanni; (Goito,
IT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
WEIGHTPACK S.R.L. |
Goito |
|
IT |
|
|
Family ID: |
57737864 |
Appl. No.: |
15/653135 |
Filed: |
July 18, 2017 |
Current U.S.
Class: |
141/83 |
Current CPC
Class: |
B65B 3/28 20130101; B65B
39/003 20130101; B67C 3/28 20130101; F16K 5/162 20130101; B65B 3/14
20130101 |
International
Class: |
B65B 3/14 20060101
B65B003/14; B65B 3/28 20060101 B65B003/28 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 19, 2016 |
IT |
102016000075547 |
Claims
1. A filling device for filling machines comprising a hollow body
in which a delivery member is movably inserted, wherein the hollow
body comprises a lower portion comprising a delivery duct that ends
with a delivery opening, said lower portion being intercepted by a
cone-shaped rotating shutter comprising a major base, a minor base
and a through hole aligned with the delivery duct when the filling
device delivers a product, wherein the minor base of the rotating
shutter is associated with a drawing system that applies to said
minor base a drawing force that is constant and predetermined.
2. The device according to claim 1, wherein the filling device is
inserted in a net weight filling linear or rotary type machine.
3. The device according to claim 1, wherein the rotating shutter is
set in motion by an actuator member.
4. The device according to claim 3, wherein the actuator member is
a linear actuator or a pneumatic actuator.
5. The device according to claim 1, wherein the drawing system
comprises pressurizing means acting on a piston for pulling the
minor base of the rotating shutter.
6. The device according to claim 5, wherein the drawing system
comprises a pin fixed to the minor base of the rotating shutter,
the piston being coupled at the distal end of the pin, wherein the
piston is axially movable within a cylinder comprising a sealing
portion in which the pin slides, and a chamber between the sealing
portion and the inner face of the piston comprising an inlet
opening for pressurized fluid or compressed air, wherein the
pressure is constant and predetermined.
7. The device according to claim 6, wherein the piston is axially
retained by stop rings, while allowing the pin to rotate integrally
with the rotating shutter.
8. The device according to claim 1, wherein the drawing system
comprises a hollow element comprising a vacuum chamber onto which
the minor base of the rotating shutter overlooks, wherein the
vacuum chamber comprises an opening connected to a vacuum means,
wherein the applied vacuum is constant and predetermined.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to Italian Patent
Application No. 102016000075547 filed on Jul. 19, 2016, the
disclosures of which are hereby incorporated by reference in their
entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to a filling device for
inhomogeneous products or products which have solid or semisolid
elements of variable size and compactness in suspension. The valve
of the invention can be used in net weight filling machines.
STATE OF THE ART
[0003] The use of weight filling systems with inhomogeneous
products or products which have solid or semisolid elements of
variable size and compactness in suspension is rather
problematic.
[0004] The known weight filling methods are all characterized by
filling valves connected either to a tank or to a manifold and the
opening/closing dynamic of the valve depends on the weight
measuring strategy of the delivered product. The release of the
product from the valves is promoted by the pressure, determined
either by the geodesic head of the product itself or by a slight
pressurization (a few meters of water column at most) of the tank
or of the manifold which supplies the product to the valves.
[0005] Inhomogeneous products, in addition to needing to be
constantly mixed to avoid the layering of the solid parts due to
the difference of density, have the problem that some pieces tend
to aggregate near the outlet of the valves, compromising the
correct filling strategy.
[0006] In order to guarantee continuity of this operation, a
pressurization regime which is incompatible with the weight
measuring systems, but is typical of volumetric filling systems
must be applied to the product. This type of method is based on
volumetric piston systems.
[0007] There are various types of volumetric piston valves,
according to whether the delivery opening is closed by a shutter
with linear movement or whether a rotating valve is provided.
[0008] This second type of valve normally provides the arrangement
of a cone-shaped rotating shutter. This shape allows a better
coupling with the housing in which it must rotate and also a better
sealing in case of thermal deformation of the material.
[0009] The cone-shaped shutters of these type of valves are
typically held in their operating position, in coupling with the
respective housing, by a preloaded spring. However, a drawback
relative to the use of this valve has been found, because it is
subject to thermal deformation, which results in an altered sealing
pressure (either higher or lower depending on the case) and thus
also to a different friction between the surfaces of the shutter
and that of its housing. Since the actuation of such cone-shaped
shutter is normally of the pneumatic type, thus with constant load,
a variation of friction between the concerned surfaces translates
into a different rotation speed of the cone-shaped shutter with
respect to the desired speed. This constitutes a problem because
the constant delivery is altered in a manner which is difficult to
predict.
SUMMARY OF THE INVENTION
[0010] The problem addressed by the present invention is thus to
provide a filling device which solves the problems inherent to the
devices of the prior art, allowing an accurate and efficient
filling.
[0011] Such a problem is solved by a filling machine as outlined in
the accompanying claims, the definitions of which form an integral
part of the present description.
[0012] Further features and advantages of the present invention
will be apparent from the description of some examples of
embodiment, given here by way of non-limiting example.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a perspective sectional view of the filling device
of the invention;
[0014] FIG. 2 is a perspective view of the device in FIG. 1
according to a different angle;
[0015] FIG. 3 is a perspective view of a detail of the device in
FIG. 1;
[0016] FIG. 4 is a perspective sectional view of the filling device
of the invention according to a different embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0017] With reference to the figures, the filling device of the
invention, indicated by reference numeral 1, comprises a hollow
body 2, in which a delivery member (not shown) is inserted, e.g. an
auger member, as described for example in Italian patent
application N. 102015000069398 dated 5 Nov. 2015. The hollow body 2
is connected to a tank containing the product to be delivered,
which will be typically introduced into the upper portion of the
hollow body 2.
[0018] The filling device 1 is inserted in a filling machine (not
shown) of linear or rotary type, in which a plurality of filling
devices operate in sequence. Each filling device 1 is operatively
connected to a single drive, such as for example either a
synchronous or an asynchronous motor, by means of appropriate
motion transmission systems, or may be operated by its own motor,
e.g. a stepper motor or a brushless motor.
[0019] In a weight filling machine, the container is supported by a
plate operatively arranged on a loading cell for weighing the empty
and full container. However, these machines are known and will not
be described in further detail.
[0020] The hollow body 2 comprises a lower portion 2a comprising a
delivery duct 10 having narrow section with respect to the cavity
of the hollow body 2 and which ends with a delivery opening 2b.
[0021] The lower portion 2a is intercepted by a rotating shutter 3.
As also shown in FIG. 3, the rotating shutter is cone-shaped and
comprises a major base 3a, a minor base 3b and a through hole 4
arranged transversally with respect to the main axis of the shutter
3.
[0022] A cylindrical portion 3c protrudes centrally from the major
base 3a of the rotating shutter 3.
[0023] The rotating shutter 3 is rotationally housed in a
complementary shaped housing and is moved by an actuator member 5.
The outer surface of the rotating shutter 3 comprises an annular
housing in which a sealing ring 9 is housed.
[0024] In some embodiments, the actuator member 5 is a linear
actuator, preferably a pneumatic actuator. The cylinder of the
pneumatic actuator is connected, by means of a connecting rod 6, to
a cam member 7. The cam member 7 is integral in rotation with the
rotating shutter 3 and is connected to it by means of the
cylindrical portion 3c, which thus forms a connection and fixing
portion of the rotating shutter 3. In this manner, the rotating
shutter 3 may assume an opening position (shown in FIG. 2), in
which the through hole 4 is aligned with the delivery duct 10, and
a closing position, in which the through hole 4 is completely
misaligned with the delivery duct 10, e.g. assumes a transversal
position, preventing the passage of the product.
[0025] The rotating shutter 3 comprises preloading means adapted to
keep it pressed against its housing with constant load, in which
such preloading means are different from a preloaded spring and
comprise a drawing system at the minor base 3b of the rotating
shutter 3.
[0026] In some embodiments, as shown in FIG. 1, the drawing system
comprises a pin 11 fixed to the minor base 3b of the rotating
shutter 3, e.g. by means of screws 12. A piston 13 is coupled to
the distal end 11' of the pin 11. The piston is withheld axially by
appropriate stop rings 14, 14' (e.g. a washer and a snap ring),
while the pin 11 can rotate integrally with the rotating shutter
3.
[0027] The piston 13 is axially movable inside a cylinder 15. The
cylinder 15 comprises a sealing portion 15a, comprising a hole of
diameter substantially corresponding to the diameter of the pin 11
and in which the pin 11 itself slides. The hole of the sealing
portion 15a comprises a housing for a sealing ring 16.
[0028] The piston 13 comprises an outer sealing ring 17, which
ensures the sealing against the wall of the cylinder 15, and an
inner sealing ring 18, which ensures the sealing against the
surface of the pin 11.
[0029] A chamber 19 is arranged between the sealing portion 15a of
the cylinder 15 and the inner face 13a of the piston 13, the
chamber 19 comprising an inlet opening 20 of a pressurized fluid,
e.g. compressed air. The pressurized fluid is introduced by means
of an appropriate piping (not shown).
[0030] The pressurized fluid has a constant predetermined pressure
as a function of the desired positioning load of the rotating
shutter 3 in its housing. The pressurized fluid thus acts on the
piston 13 with constant load, consequently applying a constant
drawing load on the minor base 3b of the rotating shutter 3, by
virtue of the operative connection of the piston 13 with the
rotating shutter 3 via the pin 11.
[0031] In other embodiments, shown in FIG. 4, the drawing system
comprises a hollow element 22 comprising a vacuum chamber 21, which
the minor base 3b of the rotating shutter 3 faces.
[0032] The vacuum chamber 21 comprises an opening 23 connected, by
means of an appropriate piping (not shown), to vacuum means. The
applied vacuum is constant and predetermined as a function of the
desired positioning load of the rotating shutter 3 in its housing.
In this case, the vacuum directly applies a constant drawing force
on the minor base 3b of the rotating shutter 3.
[0033] The advantages of the present invention are apparent from
the description above.
[0034] While the preloaded spring traditionally used in the valves
of this type is subject to a variation of the preload caused by the
thermal expansions of the material of which it is made, the
preloading means according to the invention, i.e. the drawing
system made by vacuum pressurization at constant pressure, are
potentially independent from the thermal expansions, with the
result that the load of the shutter on the surface of its housing,
and thus also the respective friction, remains constant in all
operating conditions of the valve.
[0035] It is apparent that only some particular embodiments of the
present invention have been described, to which a person skilled in
the art will be able to make all the changes necessary to adapt it
to particular applications, without however departing from the
scope of protection of the present invention.
* * * * *