U.S. patent application number 14/397689 was filed with the patent office on 2015-12-24 for apparatus for the mechanized replacement of the sealing and cutting modules in the machines for the sealing of products in trays.
The applicant listed for this patent is GRUPPO FABBRI VIGNOLA S.P.A.. Invention is credited to ANDREA SCHIAVINA.
Application Number | 20150367975 14/397689 |
Document ID | / |
Family ID | 48184292 |
Filed Date | 2015-12-24 |
United States Patent
Application |
20150367975 |
Kind Code |
A1 |
SCHIAVINA; ANDREA |
December 24, 2015 |
APPARATUS FOR THE MECHANIZED REPLACEMENT OF THE SEALING AND CUTTING
MODULES IN THE MACHINES FOR THE SEALING OF PRODUCTS IN TRAYS
Abstract
Apparatus for the mechanized replacement of the sealing and
cutting modules in the sealing station of machines for the
packaging of products in trays, with said station comprising a
lower mold with seats for the support of the edges of the trays
with product and that by way of motion means is cyclically raised
and lowered vertically with respect to an upper mold which supports
in the lower part said modules by way of hooking and releasing
means so that said modules can be removed and replaced in a
selective manner, characterized in that said hooking and releasing
means of the modules are provided between the upper plate of each
module and the respective hooking plate of the upper mold, with
complementary mechanical engaging means of such a kind and oriented
so as to be coupled and uncoupled individually and/or
simultaneously, imparting to each said module an approaching and
separating vertical movement with respect to said hooking plate of
the upper mold.
Inventors: |
SCHIAVINA; ANDREA;
(CORREGGIO, PROVINCE OF REGGIO EMILIA, IT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GRUPPO FABBRI VIGNOLA S.P.A. |
VIGNOLA |
|
IT |
|
|
Family ID: |
48184292 |
Appl. No.: |
14/397689 |
Filed: |
March 7, 2014 |
PCT Filed: |
March 7, 2014 |
PCT NO: |
PCT/EP2014/054498 |
371 Date: |
October 29, 2014 |
Current U.S.
Class: |
53/201 |
Current CPC
Class: |
B29C 66/91421 20130101;
B29C 66/841 20130101; B29C 66/8432 20130101; B29C 66/53461
20130101; B29C 66/24244 20130101; B29C 66/7392 20130101; B29C 65/18
20130101; B65B 7/162 20130101; B65B 59/04 20130101; B29C 66/131
20130101; B29C 66/112 20130101; B29C 65/7891 20130101; B29C 66/8161
20130101; B29C 65/7451 20130101; B29C 65/305 20130101; B29L
2031/712 20130101; B29C 66/8167 20130101; B29C 66/961 20130101;
B29C 66/876 20130101; B29C 66/912 20130101 |
International
Class: |
B65B 59/04 20060101
B65B059/04; B65B 7/16 20060101 B65B007/16 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 12, 2013 |
IT |
BO2013A000105 |
Claims
1. An apparatus for the mechanized replacement of the sealing and
cutting modules in the sealing station of machines for the
packaging of products in trays, with said station comprising a
lower mold with seats for the support of the edges of the trays
with product and that by way of motion means is cyclically raised
and lowered vertically with respect to an upper mold which supports
in the lower part said modules by way of hooking and releasing
means so that said modules can be removed and replaced in a
selective manner, characterized in that said hooking and releasing
means of the modules are provided between the upper plate of each
module and the respective hooking plate of the upper mold, with
complementary mechanical engaging means of such a kind and oriented
so as to be coupled and uncoupled individually and/or
simultaneously, imparting to each said module an approaching and
separating vertical movement with respect to said hooking plate of
the upper mold.
2. The apparatus according to claim 1, provided with electric power
and signal circuits connected to the sealing unit of each module,
which in conjunction with the replacement of each module must be
opened and closed, characterized in that said circuits abut against
supplementary electric coupling means, vertically oriented and also
arranged on the upper plate of the modules and on said hooking
plate, all in such a way that while the hooking and releasing
operations of a module are carried out simultaneously the
operations of closing and opening of said electric circuits are
carried out as well, and so that all of these operations can be
easily unified mechanized and automated, using the lower mold and
the respective rising and lowering means.
3. The apparatus according to claim 1, characterized in that: each
said module is provided at the top and perpendicularly to an own
upper plate of a component such as male of at least one mechanical
engaging whose component, complementary and for example female, is
provided on a hooking plate of said upper mold which carries hooked
underneath the various modules, being provided of forced
orientation means for properly orienting said modules with respect
to the hooking plate and to said molds; said upper plate of each
module and said hooking plate carry complementary parts of
multi-polar electric coupling, of the plug and outlet type,
perpendicular to said plates and connected to the power supply and
electric control means of the sealing unit of each module; some
locking and unlocking means are provided on at least one of said
plates to cooperate with said complementary mechanical engaging
parts; a template is finally provided to be mounted with the forced
orientation means, in one of the empty seats of the lower mold and
said template is provided with means for effecting the hooking or
the release of a module to or from said hooking plate and is
provided with means for activating or deactivating said locking and
unlocking means, using the rising and lowering movement of the
lower mold with said template.
4. The apparatus according to claim 3, wherein the upper plate of
each module carries integral on the upper part and perpendicularly,
a shank of cylindrical shape, with round base, which ends with a
frustum conical head and with rounded edges and which is laterally
provided, at opposite positions, with rectilinear grooves, being
provided that the hooking plate is provided for each module with a
hole of diameter such to be crossed with good accuracy by said
cylindrical shank of the module and such that, at successful entry
of the shank into the hole, the side grooves of the same shank
would protrude from the upper face of the hooking plate on which
levers are pivoted guided by means and urged in the closing by a
spring which leads said levers to protrude with a part of their
inner sides, within said hole, so that when in said hole said shank
of the module is engaged and raised, the tapered end of said shank
would progressively enter between said levers separating them until
bringing them to cooperate with the cylindrical part of the same
shank and when the side grooves of said shank reach the height of
the levers, the latter snap enter in said grooves firmly fixing the
module under the hooking plate.
5. The apparatus according to claim 3, wherein inside said
mechanical engaging shank guide means are provided as well as the
counteracting spring for the sealing assembly of each module and on
the plate of said sealing assembly is integral perpendicularly an
anti-rotation pin which passes through a slot provided on the upper
plate of the module and which protrudes perpendicularly from the
latter to be able to removably engage in a corresponding seat of
the hooking plate to prevent also the rotation of each module
around the axis of the mechanical engaging that fixes the module
itself to the hooking plate.
6. The apparatus according to claim 3, wherein said template has
the shape of a parallelepiped and inverted box, made with any
thermosetting plastic material, provided with a flat upper wall on
which it is intended to rest the lower part of a module and
peripherally surrounded by an edge in relief for containing the
same module, being the same template provided with comfortable side
gripping handles, being provided with downward extensions of its
own side walls, with which it engages the perimeter of the seat of
the lower mold for properly centering therein the same template
which with own corner portions rests on the upper face of the plate
with the seats of the lower mold, which in this way takes over the
mechanical support function of the template, being provided on one
of said corner portions of the template a projecting vertical pin
which engages a hole provided only on one of the portions with
which said plate supports the corner areas of the same template, so
that the latter results arranged on the lower mold with a forced
and useful orientation for properly cooperating with a module both
in the hooking step and in the releasing one to or from said
hooking plate of the upper mold.
7. The apparatus according to claim 6, wherein the template is
provided laterally, for example on the half of one of its sides,
with a first plate which extends above the peak of the same
template and that carries open on the upper part a vertical and
median slit in which a side reference of the module is inserted to
be hooked or released, being provided that in opposed and parallel
to said first plate, the template carries laterally fixed a second
rectangular and projecting plate which carries two upwardly open
slits in which a corresponding pair of side references of the same
module are engaged which in this way is properly oriented with
respect to the template and with respect to the hooking plate of
the upper mold.
8. The apparatus according to claim 7, wherein the template used
for releasing a module has the first side plate higher than said
second plate and the same first plate is provided at the top with
oblique sides adapted to cooperate with end extensions of said
levers operating on the hooking plate for locking the mechanical
engaging of each module, to determine the mutual separation of said
levers in contrast with the action of the respective closing
spring, with the resulting output of said levers from the side
slots of the shank of the module and the consequent releasing of
the same module that by falling on the near peak of the template,
lowers said slots so that when the lower mold with the template
comes down with the released module and said levers gradually
close, said levers slide on the cylindrical portion and then on the
conical portion of the shank, returning to the projecting position
within the hole of the hooking plate, useful for the snap
cooperation with the new module to be hooked.
9. The apparatus according to claim 8, characterized by comprising
sensors or micro-switches and a respective electric and/or
electronic circuit to ensure that in the event of non-compliance
with the orientation protocol of the template on the lower mold and
of the module on the same template, the movement of the lower mold
is automatically stopped and acoustic and/or visual signals are
activated to indicate the type of malfunction occurred.
10. The apparatus according to claim 2, wherein the plug and the
outlet of said vertical electric coupling are provided with
respective insulating bodies that cross the respective vertical
windows provided on the upper plate of the module and on the
hooking plate and said insulating bodies are provided with
respective base widening which are respectively maintained abutting
under the upper plate and above said hooking plate, by driving
screws and by respective counteracting springs whose thrust force
is greater than the coupling friction of the electric coupling in
question, the whole in such a way that when the upper plate of a
module is raised against the hooking plate, the plugs fit into the
corresponding bushings of the electric coupling and the protruding
parts of the insulating bodies of said coupling touch each other
and push away their bases from the plates, forming a clearance of a
width such as to compensate for the clearance that is formed
between the same plates during the work cycle of the module and
which derives from the clearances existing between said hooking
levers and the corresponding slots of the shank engaged by said
levers, so that during the same working cycle of the module said
insulating bodies move through respective apertures remaining
always in contact one with the other, with no relative axial
movements between the plugs and the respective outlet bushings.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to PCT International
Application No. PCT/EP2014/054498 filed on Mar. 7, 2014, which
claims priority to Italian Patent Application No. BO2013A000105
filed Mar. 12, 2013, the entirety of the disclosures of which are
expressly incorporated herein by reference.
STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT
[0002] Not Applicable.
BACKGROUND OF THE INVENTION
[0003] The invention relates to the so-called tray sealers, namely
to machines that seal with a cover film pans or trays filled with a
product to be packaged, such as a food product. In particular the
invention finds application in the sealing station of these
machines, usually provided with a lower horizontal mold, provided
with compartments open upwards wherein pliers insert and set in
support, with their peripheral edge, trays filled with a product
and provided with an upper and opposed mold to the previous one,
under which passes a film of thermoplastic material coming from a
feed reel arranged above and in correspondence to one end of said
upper mold and connected to a collecting take-up reel also arranged
above and in correspondence to the other end of the same upper
mold, inside which the heat-sealing and cutting means are arranged,
which after the rising of the lower mold, respectively close each
tray by heat-sealing on its peripheral edge a portion of the
interposed film and then cut around the perimeter and outside of
the sealing said closing film portion, to separate it from the
continuous film, so that when the lower mold lowers, the trays
closed with the heat-sealed film remain therein, that by way of
extractors are arranged in a raised position for the gripping by
way of a part of said pliers that, while performing said feeding
step of new trays to be closed, transfer the sealed trays from the
sealing station in a subsequent unloading station. The waste of the
film portion arranged under the upper mold, is cyclically advanced
so as to be moved away towards the downstream collecting means and
to be replaced by a new portion of intact film coming from the
upstream supply means.
[0004] The tray sealers are typically arranged to operate
cyclically on assemblies of trays formed by many trays arranged on
a row or on two or more parallel rows. The technical problems that
occur most frequently in these machines, are due to the necessity
of having to replace the cutting means or the electrical
resistances of the upper cutting and sealing means and to simplify
the resolution of these problems, the tendency is to arrange the
cutting and sealing assemblies as modules, to be mounted removably
on a single hooking plate associated with the upper mold and which
carries the electrical systems, so that in case of a malfunctioning
module it can be replaced quickly without having to move the other
sealing and cutting modules. This same trend also facilitates the
so-called format-change operations of the tray sealers, involving
replacement of the cutting and sealing modules to vary the size of
the trays to be sealed.
[0005] As state of the prior art, we mention the Japanese patent JP
3743880 B2 with priority date Jul. 10, 2000 and the publication of
the patent application U.S. 2011/0072764A1 deposited in Sep. 28,
2010. In this latter prior art is described how the sealing and
cutting modules are provided with handles so as to be easily
assembled and disassembled, and how their electric power supply and
control cables are connected to an outlet arranged laterally to the
modules upper hooking structure in order to facilitate maintenance.
This document does not describe how the modules are fixed to said
upper support structure. From the observation of an advertising
catalog taken from Internet, the machine IN50 of the American firm
ROSS, holder of the patent application U.S. 2011/0072764A1, it
seems that the sealing and cutting modules are mounted on the
support structure having a drawer-like solution, with the ability
of sliding on horizontal guides and perpendicular to the
advancement direction of the trays, and then with the possibility
of engaging and extraction from one or both sides of the machine.
In this same prior solution, the replacement of the cutting and
sealing modules must be done manually, with considerable loss of
time for releasing and mechanically re-fixing the modules, for
opening and closing the electrical connections and allowing first a
sufficient cooling of the module to be replaced in order to avoid
dangerous burns to the maintenance personnel. This same solution
cannot be applied on sealing and cutting assemblies acting on more
than two rows of trays, as for accessing the modules of the inner
rows the modules of the external rows should be removed. It is then
evident how this same solution requires wide free space on the
sides of the machine, in order to perform said drawer-like
engagement and extraction operations of the sealing and cutting
modules.
SUMMARY OF THE INVENTION
[0006] The invention provides to obviate the limitations and the
drawbacks of the known art, with the solution described in the
annexed claim 1 and subsequent dependent claims, which exploits the
following solution idea. The sealing and cutting modules are
provided with mechanical engaging means which presuppose a vertical
movement of the modules themselves and each module is provided with
a vertical electric plug which engages in a corresponding
electrical vertical outlet arranged on the modules upper hooking
plate, to achieve the necessary electrical connection of the
removable electrical power and signal systems. To disassemble a
cutting and sealing module, a forced orientation in the seat of the
lower mold is arranged which would receive the tray and which is
aligned vertically with the module to be replaced, a template, all
or in part of insulating plastic material, provided with
comfortable side handles and having a shape complementary to the
bottom one of the cutting and sealing module to be replaced and
when said template is lifted up with the rising of the lower mold,
the same template is available under the module to be replaced and
with means associated thereto, releases the module from the upper
support plate, so that the module is arranged in a centered support
on the template which is then sent down and is removed with the
module to be changed, which may also be hot as the template is in
thermo-insulating material and can be safely grasped, even with
bare hands by way of its side handles. During the release of the
mechanical hooking means of the module to the upper support plate
and during the next downward stroke of the lower mold, the
electrical plug of the module slips off automatically from the
upper outlet, therefore the whole operation of extraction of the
module can be mechanized and can be performed quickly and safely.
For the hooking of a new cutting and sealing module, this is
arranged with a forced orientation on a support template, which is
mountable with forced guidance too in the empty seat of the lower
mold, which is then raised to hook the module to the upper hooking
plate and to engage its corresponding plug in the electric outlet
of the same upper hooking plate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Further characteristics of the invention and the advantages
deriving therefrom, will appear more evident from the following
description of a preferred embodiment thereof, illustrated purely
by way of non-limiting example, in the figures of the six attached
drawing sheets, wherein:
[0008] FIG. 1 shows in perspective and from above a cutting and
sealing module according to the invention;
[0009] FIG. 2 shows in perspective from above a portion of the
module support and hooking plate of FIG. 1, with one of said
modules mounted;
[0010] FIG. 3 shows other details of the assembly of FIG. 2
sectioned along the line III-III;
[0011] FIG. 4 shows with mild lateral perspective and from above,
the template used for the release of a cutting and sealing
module;
[0012] FIG. 5 shows the two molds of the machine arranged to
operate on two tray rows sectioned along the line V-V of FIG. 2,
with a template arranged in a compartment of the lower mold shown
in the low resting position;
[0013] FIG. 6 shows in perspective and from above the same means of
FIG. 5, limitative to a cutting and sealing module and at the end
of the rising stroke of the lower mold;
[0014] FIG. 7 shows the same means of FIG. 6 sectioned along the
line VII-VII;
[0015] FIG. 8 shows the same means of FIG. 7 in the lowering step
of the lower mold with the template and with the cutting and
sealing module released from the upper mold hooking plate;
[0016] FIG. 9 shows the same means of FIG. 8 in the next hooking
step of a new cutting and sealing module on the upper mold hooking
plate;
[0017] FIGS. 10 and 11 show enlarged details of the hooking system
of the cutting and sealing module, shown respectively in the
engaging condition as indicated by broken lines in FIG. 9 and after
the engaging step, when the module is supported by the upper
hooking plate;
[0018] FIG. 12 shows the electrical plug of each module
transversely sectioned, engaged in the respective plug of the
hooking plate, when said plate touches the module as in the
condition of FIG. 10.
DETAILED DESCRIPTION OF THE INVENTION
[0019] With reference to FIGS. 1 to 3 it is noted that each sealing
module M comprises an upper plate 1 with a plan shape correlated to
that of the die F for the perimetral cutting of the sealing lid of
the trays by the sealing machine that engages said module M and at
the center of the plate 1 is superiorly integral and protrudes
perpendicularly therefrom, a shank 2 of cylindrical shape, with a
round base, with height greater than the thickness of the hooking
plate 3 of the module M (see below), which ends with a
frustoconical head 102 and with flared edges and which is laterally
provided, in opposite positions and with parallel orientation to
two sides of the module, for example the shorter sides, with
rectilinear grooves 4, 4' of equal size and equally spaced from the
underlying plate 1. Seen transversely and in the median area, the
grooves 4, 4' have a U section and their parallel sides are
perpendicular to the axis of the shank 2. The free edges of the
grooves 4, 4' are suitably beveled. As illustrated in detail in
FIG. 3, the shank 2 is provided axially with a guide seat 5 in
which a spark plug 6 axially slides having a bearing head 106 on
said shank 2 and that with the lower end is removably fixed with
suitable means 9, to the central part of the plate 110 that carries
the sealing frame 10 oriented downward and heated by the electric
resistance 11. A counteracting spring 12 strikes the spark plug 6,
reacting on the upper part against a seat of the shank 2 and with
the lower end acting on the plate 110 to maintain the sealer 10 in
the low resting position.
[0020] To the sealer 10 is usually associated at least one
temperature control sensor, not shown in the drawings, therefore
for piloting the electric module M is necessary to provide within
the same a small electrical circuit formed by five wires: two power
wires for the power supply of the electric resistance 11; two
signal wires connected to said temperature sensor and one grounding
wire. These five wires are connected on the other end to a
penta-polar plug 13 that with its own insulating body 113 protrudes
in part from a window 14 obtained on the plate 1 (FIG. 1) and that
brings its own five metal plugs 213 protruding from said insulating
body, oriented upward and perpendicular to the plate 1 (see
below).
[0021] From FIG. 1 it is noted that the cutting and sealing module
M carries fixed perpendicularly on the support plate 110 of the
sealer 10, a pin 15 with countersunk head 115, which passes through
a slot 215 of the plate 1 and protrudes from the latter for a right
segment, both to avoid the rotation of the sealing assembly around
the axis of the spark plug 6, and for other anti-rotation purposes
mentioned later. On the side surface of the plate 1, for example on
the edges of the long sides of the latter, protruding references
have been arranged made for example by the cylindrical head of the
screws arranged for example one in the middle of one side, as
indicated with 16 and two on the opposite side, with symmetric
arrangement, as indicated with 116 and 216. It is understood that
these references can be differently formed by piece parts of the
plate 1.
[0022] With reference to FIGS. 2 and 3 it is noted that the plate 3
to which the modules M are hooked underneath, for each module is
provided with a cylindrical hole and with round section 17, of a
diameter such as to be crossed with good accuracy by the
cylindrical shank 2 of the module M and whose edges are properly
rounded. Once the shank 2 is engaged in the hole 17, the side
grooves 4, 4' of the same shank protrude from the upper face of the
plate 3 where gripping means are provided that readily engage into
said grooves to retain the module M hooked to the same plate 3. For
this purpose, on the upper face of the plate 3, on one side and on
the other side of the hole 17 small seats 18, 18' are formed by
material removal, parallel to each other and to the grooves 4, 4'
of the shank 2, which end in a recess 19 provided on one side of
the plate 3 and said seats 18, 18' have a depth slightly greater
than the thickness of flat levers 20, 20' pivoted with one of their
ends in 21, 21' within the same seats 18, 18' and which extend up
to protrude with the other end from the same side recess 19 of the
plate 3, where they present integral lower cylindrical extensions
22, 22' and where the same levers 20, 20' are interconnected by a
traction spring with cylindrical helix 23 which causes said levers
20, 20' to engage the grooves 4, 4' of the shank 2 and to retain
the module M hooked to the plate 3. Even the spring 23 is housed
without interference in said recess 19. In the hooking position of
the module M, as well as in the resting position, when the shank 2
is not engaged in the hole 17, the levers 20, 20' are maintained by
the spring 23 bearing against the inner side of their seats 18, 18'
and with a portion of their inner sides protrude inside the hole
17, so that when in said hole the shank 2 is engaged and raised,
the tapered end 102 of said shank can progressively enter between
said levers 20, 20' and widen them, until they cooperate with the
cylindrical portion of the shank 2 and when the grooves 4, 4'
thereof reach the height of the levers 20, 20', these come to snap
into the same grooves 4, 4' and firmly engage the module M to the
support plate 3 (see below). To avoid unwanted bending and
bending-torsion stress on the levers 20, 20' when these cooperate
by sliding with the shank 2, the seats 18, 18' are closed by a
small plate 24 fixed, for example by screws on the upper face of
the plate 3, as shown in continuous lines in FIG. 3 and in broken
lines in FIG. 2.
[0023] Always in FIG. 2 it is noted that the hooking plate 3 is
provided in a pre-fixed position, with a hole 25 with flared edges,
which houses the protruding segment of said pin 15 of the sealing
module M to prevent the latter from rotating on the coupling formed
by the shank 2 and the hole 17 that houses it. For the cooperation
between these same parts 15 and 25, the module M assumes a forced
and predetermined position on the plate 3, useful for the correct
cooperation of the same module M with the seat carrying the tray in
the lower mold of the sealing machine. Also for the mutual
cooperation with said parts 15, 25, the module M is arranged with
its own side reference 16 (FIG. 1) in alignment with the centerline
of said recess 19 of the hooking plate 3.
[0024] The hooking plate 3 is finally provided with an electrical
penta-polar outlet 26, whose insulating body 126 protrudes downward
from a window 27 of the same plate 3 and carries the contact metal
bushings 226 open downward and in the vertical alignment position,
useful for the coupling with the pins 213 of the electrical plug 13
of the sealing and cutting module M as shown in FIG. 1. With 28 is
indicated the bundle of electric wires connected to the outlet 26
and in abutment against the electrical panel (not shown) for
powering and controlling the sealing assembly 10 of the various
modules M hooked to the plate 3.
[0025] With reference to FIGS. 4 and 5 is now described the
equipment to be used and the respective method of use to disengage
from the hooking plate 3 a defective sealing module M. In FIG. 5 is
indicated with C1 the lower mold with the seats S that in operating
machine house each a tray to be sealed. The mold C1 is initially in
the low resting position and away from the overlying mold C2 of a
distance such that on the same mold C1 the equipment that is
described below with reference to FIG. 4 can be arranged easily. In
the upper mold C2 a plate 3 for hooking the modules M is housed
provided in number of one for each said lower seat S, which are
illustrated here in the resting position, with the sealer 10
protruding below the cutting die F. FIG. 5 shows, purely by way of
example, how the hooking plate 3 is supported by medians spark
plugs 29 sliding in the guide bushings 30 fixed on a support
structure 31 and from these bushings said spark plugs 29 protrude
upwards with a segment pushed upwards by a contrast spring 32. On
the same support structure 31 are arranged in a position
equidistant from the bushings 30, additional bushings 33 for the
sliding of the spark plugs 34 fixed to the bell 100 of the upper
mold C2 and pushed downwards by counteracting springs 35. In the
rest position, the hooking plate 3 bears against the spacers 50
integral with the bell 100 of the mold and C2 and appears evident
that there is a sufficient clearance between the upper end of the
hooking shanks 2 of the modules M and the same bell 100 whose lower
perimeter with a channel-profile 100' is arranged below the sealing
and cutting 10 assemblies of the same modules M.
[0026] Have not been illustrated in FIG. 5 the means that on
command push downwards the plate 3 with the modules M to perform
the cutting and sealing step of the trays lids, as it is not
necessary for the understanding of the invention which is expected
to operate on the upper bell C2 at rest conditions.
[0027] The equipment to be used for the purposes in question, is
illustrated in FIG. 4 and comprises a template 36 having the shape
of a parallelepiped box and inverted, made with any thermo-setting
plastic material, provided with a flat upper wall 136 on which is
intended to rest the lower part of the module M and peripherally
surrounded by a relief edge 236 for containing the same module M,
provided with comfortable grip handles 37 on the short sides, with
downward extensions 336 of its side walls, with which it engages
the perimeter of the seat S of the lower mold C1 to properly center
therein the template 36 which with its corner portions 436 rests on
the upper face of the plate 38 with the seats S, that in this way
takes over the mechanical support function of the same template 36.
On one of said corner portions 436 of the template 36 a projecting
vertical peg 39 is provided which must enter into a hole 40
provided only on one of the portions with which the plate 38
supports the corner areas of the template 36, so that the latter
will result arranged on the lower mold C1 with a forced orientation
and such that a plate 41 with which the template 36 is laterally
provided on the half of one of its long sides, which extends above
the peak 136, 236 of the template and that carries in the upper
part of the oblique sides 141 and a median slit 42, appears below
and in vertical alignment with the recess 19 (FIG. 2) of the
hooking plate 3 and with the side reference 16 of the module M
arranged therein. On half of the other long side, in opposition and
parallel to the plate 41, the template 36 carries a rectangular and
protruding plate 43, of a height less than that of the plate 41 and
provided at the top with a pair of slits 44 which are in vertical
alignment with the pair of side references 116, 216 with which the
module M is provided (FIG. 1).
[0028] After mounting the template 36 in a seat S of the lower mold
C1, as mentioned earlier with reference to FIG. 5, the rising of
the same mold C1 is controlled with a preset stroke towards the
upper mold C2 which remains stationary and the end of this rising
stroke is illustrated in FIG. 6, from which is detected how the
side references 116, 216 of the module M are engaged into the slits
44 of the plate 43, how the side reference 16 of the same module M
is engaged in the slit 42 of the plate 41 and how, before these
references touch the bottom of said slits and before the sealing
assembly 10 touches the peak 136 of the template 36, the oblique
sides 141 of the same plate 41 cooperate with the end extensions
22, 22' of the levers 20, 20', by spreading said levers and
extracting them from the side slots 4, 4' of the shank 2 of the
module M, with the result that said module is released by gravity
from the hooking plate 3 and under the guide of the side plates 41,
43 falls on the nearest upper wall 136, 236 of the template 36 that
takes over in the supporting the module, while the slots 4, 4' are
arranged below the levers 20, 20' still in the open position, as
shown in FIG. 7. When the lower mold C1 is lowered, as shown in
FIG. 8, while the oblique sides 141 of the plate 41 leave the ends
22, 22' of the levers 20, 20' and these latter are close up again,
the inner sides of said levers are to cooperate with the upper
cylindrical part and then with the conical head 102 of the shank 2,
finally abandoning the module M that descends with the lower mold
C1, resting and in the correct centering position on the template
36. While the template 36 is lowered and moves away from the
hooking plate 3, also the electrical contacts of the plug 13 detach
from the bushings of the outlet 26 of the same plate 3, thanks to
the weight of the module M that is much greater than the frictional
resistance that the plug meets by detaching from said outlet. When
the mold C1 has reached the end of the lowering stroke, it is easy
and safe for the operator, to grasp the template 36 by the handles
37 and remove this component with the module M from the seat S for
freeing it and have it ready for the next mounting step of a new
cutting and sealing module M'. Even if the extract module M is
warm, the thermo-insulating nature of the template 36 makes the
handling of the ensemble extremely safe.
[0029] The engaging step of a new module M' on the hooking plate 3,
is an operation which is also very simple and rapid, which involves
the provision in the empty seat S of the lower mold C1, of a
template 36' as from FIG. 9, which differs from the 36 used for the
releasing, for the fact that the previous plate 41 (FIG. 4) is
replaced by a plate 41' of much lower height, devoid of the upper
oblique sides since this plate 41' must not cooperate with the ends
22, 22' of the hooking levers 20, 20' and provided with a short
central slot 42' adapted to cooperate with the side reference 16 of
the new module M'. The plate opposite to that 41', indicated in
FIG. 9 by broken lines, is quite equal to that of 43 and is
provided with two upper slots 44 for the cooperation with the side
references 116, 216 of the module M' that for the cooperation
effect with these plates is correctly oriented with respect to the
holes 17, 25 and to the electric outlet 26 of the hooking plate 3.
Once the new template 36' with the new module M', correctly
oriented, is successfully mounted and oriented in the seat S of the
mold C1, the rising of the same lower mold C1 is controlled with a
preset stroke that causes the shank 2 to enter in the hole 17, to
spread the levers 20, 20' which then snap hook in the side grooves
4, 4' of the same shank 2 and that causes the plug 13 of the same
module M' to engage in the outlet 26 of the plate 3. When the lower
mold C1 is taken back into the low position, the new module M'
remains hooked to the plate 3 and, after removing the template 36'
from the seat S, the machine is ready to be put back into tension
and to return operative. It is obvious that in the release and hook
steps described of a module M, M' from and to the plate 3, the
outlet 26 is not under tension. It is also evident that the
described operations of orientation of the template, of orientation
of the module with respect to the template itself and of opening
and closing of the levers 20, 20' for the releasing and hooking
steps of the modules M, M', if desired, may be easily controlled
and monitored with electrical sensors or electric micro-switches
easily arrangeable and connectable by experts in the field, to
ensure that in the event of non-compliance with the orientation
protocol of the template 36, 36' on the lower mold C1 and/or of the
module M, M' on the same template, the movement of the lower mold
is automatically stopped and acoustic and/or visual signals are
activated to indicate the type of incident that occurred. All this
leads to the substitution operation of one sealing and cutting mold
in a tray sealer becomes of such simplicity that can be safely
performed even by non-qualified personnel, with the great economic
benefits that this entails.
[0030] In FIG. 10 is shown enlarged a side of the shank 2 of a
module M at the end of the rising stroke for the hooking of the
plate 3 to the upper mold C2. In this step, the upper face of the
plate 1 of the module M abuts against the lower face of the plate 3
and the grooves 4, 4' of the shank 2 are aligned with the levers
20, 20' and since the height dimension of each groove 4, 4' is
slightly greater than the thickness of each said lever, and because
small clearances G, G' are formed above and below said parts, the
levers 20, 20' enter without resistance and with safety in the
grooves 4, 4' and when the lower mold is lowered, the module M
moves to the condition of FIG. 11, with the upper face of the
grooves 4, 4' resting on the levers 20, 20' which take over in
supporting the shank 2 and the module M whose upper plate 1 moves
away from the lower face of the support plate 3 with a clearance
G'' of small entity, related to the abovementioned clearances G,
G'. It follows that when the cutting and sealing module works by
way of thrust on the tray for sealing the cover thereon, the plate
1 of said module comes in contact with the plate 3, as mentioned
with reference to FIG. 10. These small oscillations of the modules
M with respect to the hooking plate 3 allow that if the plug 13 and
the outlet 26 were fixed to the respective plates 1 and 3, the same
would be cyclically subjected to a small movement towards and away
one with respect to the other, with possible formation of wear in
the electric contacts and with the dangers that would follow. The
invention intends to overcome this drawback, leaving the small
clearances previously mentioned, that simplify the hooking and
releasing operations, and by mounting the plug and the electrical
outlet on respective support plates, with a floating solution, as
is now described with reference to FIG. 12. From said figure it is
noted that the plug 13 and the outlet 26 are provided with
respective base swellings 113' and 126' of their insulating body,
arranged respectively below the plate 1 and above the plate 3,
having a substantially rectangular shape in plan, provided in the
corner areas with holes for the passage of the shank of respective
screws 45, 45' screwed in holes of the respective plates 1 and 3
and having a length greater than the thickness of said bases 113'
and 126' so to fulfill a sufficient approaching and spacing
displacement with respect to the respective plates 1, 3. The holes
for the passage of said screws 45, 45' are provided with respective
widenings open towards the head of the same screws and in said
widenings springs 46, 46' are housed which push the same bases 113'
and 126' into contact with the plates 1, 3, to determine a
sufficient projection from the windows 14 and 27 of the insulating
body 113, 126 of the plug 13 and of the outlet 26. From the above
it follows that when the plate 1 of the module is raised into
contact with the hooking plate 3, as shown in FIG. 12, because the
thrust force of the springs 46, 46' is greater than the engaging
friction of the plugs 213 in the bushings 226, these components are
immediately coupled to each other and at the end of the engaging
stroke, the protruding portions of the insulating bodies 113, 126
touch each other and move away their bases 113' and 126' from the
respective plates 1, 3, forming a clearance G''' which has for
example, approximately, the value of the clearance G'' of FIG. 11,
so that when said clearance is formed between the plates 1 and 3
during the operating cycles of the sealing and cutting modules M,
the insulating parts 113, 126 of the body of the outlet and plug
assembly 13, 26 move through respective apertures 14, 27 but remain
always in contact with each other and the plugs 213 are always
fitted and axially blocked into the plug bushings 226, avoiding
relative sliding and the previously mentioned drawbacks. It is
obvious that the context of the invention also comprises the
variant embodiment which envisages that the springing of only one
of the insulating bodies of the outlet or of the plug, even if the
solution shown is to be considered preferable in that the movements
and the stresses are distributed on the two units, ensuring a lower
stressing and a longer life of the system. A further variant may
refer to the placement inversion of the plug 13 and of the outlet
26 and/or to a different orientation of these components with
respect to what illustrated in the drawings.
[0031] It is understood that the description refers to a simple,
reliable and preferred embodiment of the invention, to which
numerous variations and constructive modifications can be made, all
of which without abandoning the guiding principle of the invention,
as described, illustrated and as claimed below. In the claims, the
references between brackets are purely indicative and do not limit
the protection scope of the claims.
* * * * *