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(11) | EP 0 602 299 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Apparatus for wrapping delicate products, particularly such as soap bars |
| (57) The apparatus comprises a conveyor (1) for feeding products (2) extending with the
terminal portion (5) under the initial portion (14) of a transfer unit (10) which
is provided with clamp elements (15). An insertion device (57) places, on each product
feeded, a wrapping sheet (22) which is subsequently folded by the respective clamp
element (15). Said clamp element grip the product and the sheet and transfer them
towards further folding elements (62,63) to complete the wrapping. |
[0001] The present invention relates to an apparatus for wrapping delicate products, particularly such as soap bars.
[0002] As is known, at the output of molding machines, soap bars are mutually spaced by a constant pitch and are then deposited in seats of a conveyor which feeds them towards a wrapping machine.
[0003] A wrapping machine is essentially constituted by a flexible element which is aligned with the soap bar feeder conveyor and on which equidistant clamps are arranged; said clamps pick up the wrapping sheets from a feeder unit and place them horizontally above each incoming soap bar. After the placement of the wrapping sheets on the soap bars, appropriate folding elements close the wrapping. A wrapping machine of this type is described for example in Italian patent no. 906563.
[0004] Apart from a considerable structural complexity, wrapping machines of the described type have the substantial disadvantage that the distance between the clamps is excessive and cannot be reduced due to constructive reasons, so that problems in timing with respect to the incoming soap bars arise; these problems in practice lead to a reduction in the processing rate and, ultimately, to the impossibility of fully exploiting the potential of the molding machine.
[0005] The technical aim of the present invention is therefore to provide an apparatus for wrapping delicate products, particularly a wrapping machine for soap bars, which allows to obviate the shortcomings peculiar to conventional machines, i.e. is less complicated and faster.
[0006] This aim is achieved by an apparatus for wrapping delicate products, particularly such as soap bars, which comprises: a product feeder conveyor which is provided with equidistant seats for receiving the individual products; a transfer unit which is closed in a loop and has an initial portion which is aligned with, and superimposed on, the terminal portion of said feeder conveyor; a plurality of clamp elements which are mounted on said transfer unit at a mutual distance equal to the distance between the products on said conveyor; said conveyor and said transfer unit having an equal speed and being mutually in step so that along said overlapping portions a product is arranged opposite to each clamp; an abutment arranged at each clamp element; means for feeding wrapping sheets; means for placing each wrapping sheet under a respective abutment; means for lifting the individual products from their respective seats towards the opposite abutments, so that each wrapping sheet remains secured between a product and the related abutment; means for actuating said clamp elements so as to wrap and grip said products and transfer them towards folding elements to complete the wrapping; said apparatus being characterized in that said wrapping sheet placement means comprise a sheet insertion device which extends toward the point of tangency between said conveyor and said transfer unit, said insertion device being adapted to insert the wrapping sheets between each product and the opposite abutment so that each sheet has a flap in front of the respective product and one behind said product when it is secured between a product and the opposite abutment.
[0007] Further peculiarities of the invention will become apparent from the following description of a preferred embodiment, illustrated only by way of non-limitative example in the accompanying drawings, wherein:
figure 1 is a partially schematic lateral elevation view of the apparatus;
figure 2 is an enlarged-scale view of a detail of figure 1;
figure 3 is a view of the apparatus of figures 1 and 2 directly associated with a soap bar molding machine.
[0008] With reference to the above figures, the apparatus comprises a conveyor 1 for feeding the products 2, which in the specific case are constituted by soap bars which arrive from a molding machine 3 with which the apparatus is associated. Conveniently, said molding machine is provided with a soap bar unloading system according to Italian patent no. 1,215,811 in the name of the same Applicant.
[0009] The conveyor 1 is composed of a flexible element 4 (for example a pair of chains or belts) which has a horizontal upper section with a terminal portion 5 which moves in the direction A.
[0010] Seats 6 for the soap bars 2 are distributed with a pitch P along the conveyor 1; each seat is formed by a pair of wings 7 and 8 which are articulated to the flexible element 4 and are shaped so as to accommodate the soap bars 2 arriving from the molding machine 3 and keep them in position. Along the upper section of the flexible element, the wings 7 and 8 are kept upright by means of stationary cams (not shown) so as to form the seats 6. At the end of the upper section, proximate to the pulleys 9 for guiding the flexible element 4, the cams open the wings 7 and 8 to release the soap bars and allow their further advancement by means of a transfer unit, generally designated by the reference numeral 10.
[0011] Said transfer unit 10, too, is constituted by a flexible element 11 (for example chains or belts) which is wound in a loop around two pulleys 12 and 13 so that it is co-planar to the conveyor 1. The transfer unit 10 comprises a lower section which is parallel to the upper section of the conveyor 1 and has an initial portion 14 which overlaps the terminal portion 5 of the conveyor 1.
[0012] The transfer unit 10 and the conveyor 1 are actuated with identical and opposite speeds, so that their lower and upper sections move with nil relative speed in the same direction A.
[0013] A plurality of clamp elements 15 is distributed along the flexible element 11; clamp each element is composed of a pair of articulated jaws 16 and 17 between which abutments 18 are arranged.
[0014] The clamp elements 15 have the same pitch P as the seats 6, and the conveyor 1 is in step with the transfer unit 10 so that a respective clamp element 15 is vertically aligned along the overlapping portions 5 and 14.
[0015] It should be noted that the abutments 18 are arranged at a slightly higher level than the top of the soap bars 2, so that a gap is left between the soap bars and the abutments; due to reasons specified hereinafter, this gap is recovered by lifting the soap bars from their location within the seats 6 against the abutments 18.
[0016] For this purpose there is a third flexible element 19 which is closed in a loop and extends in the same direction and at the same speed as the conveyor 1.
[0017] Said element 19 is wound around a pulley which is coaxial to the pulleys 9 and around a pulley 20 which is supported ahead of the point B at which the flexible element 11 of the transfer unit 10 arranges itself parallel to the flexible element 4 of the conveyor 1.
[0018] Elastic supports 21 are distributed on the flexible element 19, have the same pitch as the seats 6 and are in step with them. Said flexible element 19 is timed and guided so as to move the supports 21 below the respective soap bars 2 and then raise them by means of stationary cams (not shown) until contact is made with the abutments 18 of the clamp elements 15.
[0019] In this manner it is possible to retain, between each abutment 18 and the related soap bar 2, a wrapping sheet 22 which is fed by means of an appropriate device generally designated by the reference numeral 23.
[0020] In the illustrated example, it is assumed that the wrapping sheet 22 is formed by mutually coupling two strips 24 and 25 which are taken from respective rolls 26 and 27 (figure 3) and are directed, through respective series 28 and 29 of movable rollers which act as compensation devices, tension rollers 30 and 31 and pairs of unwinding rollers 32 and 33 toward a rotating blade 34 which cuts segments of the required length which indeed constitutes the wrapping sheets 22.
[0021] A separation and orientation device 35 (hereinafter simply termed separator), arranged downstream of the blade 34, mutually spaces the sheets at the exit of the rotating blade 34 and orientates them from a horizontal entry position to a vertical exit position.
[0022] The separator 35 is composed of a flexible element, for example belts 36 (or other equivalent flexible element) which are wound around pulleys 37, 38, 39 and 40 which are arranged so that the belts 36 have a four-sided configuration, with a horizontal upper side 41 and a lateral side 42 which is arranged vertically and continues downward, forming a side 43 which is oblique with respect to the vertical.
[0023] Sprung rollers 44 are arranged in contact with the sides 41 and 42 and, in cooperation with the belts 36, grip the sheets and guide them toward an intermittent actuation unit 45.
[0024] The intermittent actuation unit 45 is constituted by a pair of contra-rotating rollers 46 and 47 whose plane of tangency is co-planar to the vertical plane defined by the side 42 of the separator 35.
[0025] A further unit 48 is arranged after the intermittent actuation unit 45, defined as the sorting unit, since the sheets which arrive from the intermittent actuation unit 45 mutually partially overlap inside it. Said unit 48 is composed of a further series of sprung rollers 49 which are arranged on a vertical plane and in front of which a flexible element 50 is tangentially in contact; said flexible element is for example composed of belts or other devices closed in a loop around a set of three pulleys 51, 52 and 53.
[0026] Said pulleys 51, 52 and 53 are arranged so that the flexible element 50 has a vertical section 54 in tangential contact with the rollers 49 and an upper section 55 which is inclined with respect to the vertical and forms a sort of a funnel together with the upper rollers of the series 49.
[0027] The belts 36, the flexible element 50 and the rollers 46 and 47 are actuated by means of an intermittent actuation device 56 so as to intermittently activate the rollers 46 and 47 with a tangential speed equal to that of the belts 36 when they receive the sheets 22 from said belts and so as to then reduce said speed as soon as the sheets have left the element 36 and subsequently bring it to the same speed as element 50 when the sheets are picked up by the sorting unit 48.
[0028] The described apparatus is completed by a device 57, hereinafter termed insertion unit, which places the sheets 22 between the soap bars 2 and the abutments 18.
[0029] Said insertion unit 57 is constituted by a flexible element, for example by a pair of belts 58 closed in a loop about pulleys 59 and 60 arranged so that the upper section of the belts extends downwards from the output of the flexible element 50 to the point of tangency B of the conveyor 1 with respect to the transfer unit 10. Conveniently, the pulleys 60 for guiding the belts 58 have a minimal diameter in order to allow to move the output of the insertion unit 57 as close as possible to the point of tangency B.
[0030] In order to retain the sheets on the upper section of the belts 58 there is a plurality of rollers 61 in tangential contact therewith. The speed of the flexible element 50, of the belts 58, of the conveyor 1 and of the transfer unit 10 are perfectly identical, so that the sheets 22 arrange themselves over the soap bars with zero relative speed.
[0031] The operation of the described device is as follows. The sheets 22, which are cut from the strips 24 and 25 by means of the rotating blade 34, are mutually spaced and directed by the separator 35 between the rollers 46 and 47 of the intermittent actuation unit 45 and are guided between the rollers 49 and the flexible element 50. As soon as the sheets 22 leave the separator 35, the speed of the rollers 46 and 47 is reduced and becomes equal to the speed of the sorting unit 48.
[0032] Since the plane of tangency between the rollers 49 and the vertical portion 54 of the flexible element 50 is slightly offset with respect to the plane of tangency of the rollers 46 and 47, the sheets 22 which descend initially make contact with the inclined section 55 and are then guided laterally by said inclined section before being gripped between the rollers 49 and the portion 54.
[0033] However, since the advancement speed of the sorting unit 48 is lower than the descent speed of the belts 36, the terminal flap of the sheet previously gripped between the rollers 49 and the flexible element 50 overlaps the initial flap of the sheet which is lowered by the rollers 46 and 47, so that the sheets which enter the insertion unit 57 have mutually overlapping leading and trailing edges and are inserted between the soap bars 2 and the respective abutments 18 in this configuration.
[0034] The rate at which the sheets are fed by the insertion unit 57 is such that in the point of tangency B the central region of the sheets, i.e. the one which does not overlap the other regions, is arranged between the soap bar and the abutment. Upon the subsequent lifting of the elastic supports 21, the sheets 22 remain secured at said central region.
[0035] During subsequent travel up to the pulleys 9, the jaws 16 and 17 of the clamp elements 15 are actuated so that they close; said clamp elements cause the downward folding of the front and rear flaps of the sheets and the gripping of the soap bars, which can thus be transferred downstream toward the folders 62 and 63 which complete the forming of the package.
[0036] A substantial prerogative of the invention is constituted by the fact that the overlap of the sheets along the section which corresponds to the portions 5 and 14 allows to move the grip elements 15 significantly closer together, with considerable advantages in productivity. The structure of the conveyor 10 is furthermore considerably simplified, and said conveyor no longer requires clamps for picking up the sheets and placing them on the soap bars.
[0037] In the practical embodiment of the invention, the shapes and dimensions may vary according to the requirements.
[0039] Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the scope of each element identified by way of example by such reference signs.
1. Apparatus for wrapping delicate products, particularly such as soap bars, which comprises:
a conveyor (1) for feeding products (2) which is provided with equidistant seats (6)
for receiving the individual products; a transfer unit (10) which is closed in a loop
and has an initial portion (14) which overlaps and is aligned with the terminal portion
(5) of said feeder conveyor (1); a plurality of clamp elements (15) which are mounted
on said transfer unit (10) and have a mutual distance equal to the distance P of the
products (2) on said conveyor (1), said conveyor (1) and said transfer unit (10) having
an equal speed and being mutually in step so that a product (2) is arranged opposite
to each clamp (15) along said overlapping portions (5, 14); an abutment (18) arranged
at each clamp element (15); means (23) for feeding wrapping sheets (22); means for
placing each wrapping sheet (22) below a respective abutment; means (19) for lifting
the individual products (2) from their respective seats (6) toward the opposite abutments
(18), so that each wrapping sheet (22) remains secured between a product (2) and the
related abutment (18); means for actuating said clamp elements (15) so as to wrap
and grip said products (2) and transfer them towards folding elements (62, 63) to
complete the wrapping; said apparatus being characterized in that said wrapping sheet
placement means comprise an insertion device (57) for the sheets (22) which extends
toward the point of tangency (B) between said conveyor (1) and said transfer unit
(10), said inserter (57) being suitable to insert the wrapping sheets (22) between
each product (2) and the opposite abutment (18), so that each sheet (22) has a flap
in front of the respective product (2) and one behind said product (2) when it is
secured between a product (2) and the opposite abutment (18).
2. Apparatus according to claim 1, characterized in that said wrapping sheet feed means
comprise an intermittent actuation unit (45) which is composed of a pair of contrarotating
rollers (46, 47) which have a vertical plane of tangency and are suitable to provide
single sheets (22) with a rate and a timing which correspond to those of said conveyor
(1) and of said transfer unit (10), a unit (48) for sorting the wrapping sheets (22)
being arranged after said intermittent actuation unit (45), said sorting unit (48)
comprising a flexible element (50) which has a vertical section (54) on which a plurality
of sprung rollers (49) is tangentially in contact and an oblique section (55) which
extends from said vertical section (54) toward said intermittent actuation unit (45)
so as to define a guide for the sheets (22) released by said unit, said intermittent
actuation unit (45) and said sorting unit (48) being actuated so that the initial
portion of the sheet (22) released by the intermittent actuation unit (45) overlaps
the terminal portion of the sheet (22) previously released and gripped between said
flexible element (50) and said plurality of rollers (49).
3. Apparatus according to claim 2, characterized in that said insertion unit (57) is
constituted by a flexible element (58) which has an upper section which extends from
the output of said sorting unit (48) toward the point of tangency (B) between said
conveyor (1) and said transfer unit (10), said flexible element (58) being closed
in a loop around guiding pulleys (59, 60) of which those (60) which are proximate
to said point of tangency (B) have a minimal diameter.
4. Apparatus according to one of claims 2 and 3, characterized in that a unit (35) for
separating and orientating the sheets (22) is arranged ahead of said intermittent
actuation unit (45) and is suitable to mutually space the sheets cut by a cutting
device (34) and to direct them vertically along the plane of tangency of said contrarotating
rollers (46, 47).
5. Apparatus according to claim 4, characterized in that said separation and orientation
unit (35) comprises a flexible element (36) which has a horizontal section aligned
with said cutting device (34) and a vertical section (42) which is co-planar with
respect to the plane of tangency of said contrarotating rollers (46, 47), a plurality
of sprung rollers (44) being tangentially in contact on said horizontal section (41)
and on said vertical section (42).
6. Apparatus according to one of claims 4 and 5, characterized in that said intermittent
actuation unit (45) is actuated so that the contrarotating rollers (46, 47) have a
first tangential speed which is equal to that of said separation and orientation unit
(35) when they receive the sheets (22) from it and a second tangential speed which
is equal to that of said sorting unit (48) when the sheets (22) have left said separation
and orientation unit (35).
7. Apparatus according to one of claims 1 to 6, characterized in that the speed of said
conveyor (1) and of said transfer unit (10) is equal to that of the wrapping sheets
(22) at the output of said insertion unit (45), so that the wrapping sheets are superimposed
on the soap bars (2) with nil relative speed.
8. Apparatus according to one of the preceding claims, characterized in that said feeder
conveyor (1) is directly associated with a machine (3) for molding soap bars which
is provided with a soap bar unloading system according to Italian patent no. 1,215,811.