Method and installation for fitting a stretchable sleeve around objects of different diameters

Abstract

Method and installation for fitting a stretch sleeve around objects of different diameters. The method comprises the following steps: - equip a former (8) with movable arms (9) with a stretch sleeve (2) to be fitted around an object; - adjust the gap section of the former (8) to an entry section of the object; - bring the movable arms (9) of the former into contact with the entry section of the object; - bring the stretch sleeve (2) into contact with the gap section of the former; - blow compressed air to create a localized air cushion at the entry section of the object, between the stretch sleeve (2) and the object (3); - grip the stretch sleeve (2) at the air cushion; - and apply a tensile force to the sleeve (2) to secure it. Figure for the abbreviation: Fig. 6

Description

Title of the invention: Method and installation for placing a stretchable sleeve around objects of different diameters Technical field

[0001] The present invention relates to the technical field of applying stretch labeling sleeves to objects of generally cylindrical shape, such as bottles, cans or drums, for example. Prior art

[0002] The state of the art has proposed numerous solutions for ensuring the installation of stretchable sleeves around objects. For example, patent FR 2 723 913 discloses a method and a machine comprising a pair of stretchers intended to be introduced inside the sleeve. These stretchers comprise a network of channels connected to a means for blowing pressurized air opening onto the surface of the stretchers coming into contact with the sleeve to allow distribution of the stretching of the sleeve over its entire periphery. These stretchers also comprise a network of channels connected to a suction means and opening onto the surface of the stretchers coming into contact with the sleeve. These channels are placed under vacuum in order to suck the internal wall of the sleeve which thus remains firmly fixed to the external wall of the stretchers during their downward movement.The installation process described by such a patent therefore consists of stretching the sleeve transversely and slipping it onto a bottle in the stretched state. This sleeving technique leads to damage to the sleeve. Furthermore, this machine has a relatively complex design and does not allow it to easily adapt to objects of different diameters.

[0003] Patent FR 2 631 924 describes a method and an installation suitable for sleeving packaging of different sizes using stretchable sleeves. This installation comprises in particular a laying head comprising fingers arranged in a circle, extending parallel to each other over a length at least equal to the height of the sleeves. This installation comprises means for simultaneously moving the fingers along radial trajectories making it possible to adapt to the size of the sleeves to be stretched surrounding the fingers. If the technique disclosed by this patent makes it possible to adapt to objects of different diameters, the proposed solution leads to a stretching of the sleeve over its entire height which is likely to harm the quality of installation of the sleeve. Furthermore, this solution proves to be relatively complex and expensive to implement. Statement of the invention

[0004] The present invention aims to remedy the drawbacks of the state of the art in proposing a new process for placing a stretchable sleeve around objects with different diameters while avoiding damaging the sleeve through excessive stretching force.

[0005] To achieve such an objective, the subject of the invention proposes a method for placing a stretchable sleeve around an object, using a shaper with movable arms delimiting by their free ends, an adjustable spacing section for the stretchable sleeve, the method comprising the following steps: - equip the conformer with a stretchable sleeve; - adjust the gap section of the conformer to an entry section of the object corresponding to the part of the object from which the stretchable sleeve is sleeved - bring the free ends of the movable arms of the conformer into contact with the entry section of the object; - bring the stretchable sleeve into contact with the spacer section of the conformer; - blowing pressurized air at the free ends of the arms of the conformer to create a localized air cushion at the entry section of the object, between the stretchable sleeve and the object; - ensure the grip of the stretch sleeve in its part located at the level of the air cushion; - and exert a tensile force on the stretchable sleeve to translate it until the stretchable sleeve is sleeving around the object.

[0006] Advantageously, after the sleeving operation, the free ends of the movable arms of the shaper are released from the object to ensure the removal of the sleeving object and the installation of a new object to be sleeving.

[0007] Typically, the gap section of the conformer is adjusted by unfolding the movable arms between a minimum gap section and a maximum gap section.

[0008] According to an advantageous variant, an adjustment phase is carried out for an object format comprising the following steps: - provide a conformer comprising movable arms distributed angularly along the circumference of a slide guided in vertical sliding on a guide system, the movable arms being mounted articulated so that the movement of the slide in one direction causes the movable arms to deploy while the movement of the slide in the opposite direction causes the movable arms to fold back, - move the slider to adjust the gap section of the conformer to the entry section of the object; - moving the slide guide system in order to bring the free ends of the movable arms of the conformer into contact with the entry section of the object while the spacing section of the conformer corresponds to the entry section of the object; - and lock the slide guide system in position.

[0009] Preferably, after the adjustment phase, for each object to be sleeved of the same format: - a stretchable sleeve is put on the conformer; - an object to be sleeved is positioned; - the slider is moved in order to bring the free ends of the movable arms of the conformer into contact with the entry section of the object while the spacing section of the conformer corresponds to the entry section of the object; - the stretchable sleeve is moved to the entry section of the object; - pressurized air is blown at the free ends of the movable arms of the conformer to create the localized air cushion; - a tensile force is applied to the stretchable sleeve in its part located at the level of the air cushion to translate it until the stretchable sleeve is sleeving around the object; - the slide is moved to ensure the folding of the mobile arms; - the sleeved object is removed; - and a new stretch sleeve is put on the conformer.

[0010] Typically, pressurized air is blown toward the extension of the free ends of the movable arms of the former to create the air cushion.

[0011] Another object of the invention is to provide an installation for placing a stretchable sleeve around objects of different diameters, with limited tooling while maintaining the integrity of the stretchable sleeve.

[0012] To achieve this objective, the subject of the invention proposes an installation for placing a stretchable sleeve around an object, comprising: - a fixed support delimiting a placement plane for the object; - a shaper supported by the fixed support to be positioned above the laying plane, the shaper comprising movable arms distributed angularly according to the circumference of a slide guided in vertical sliding on a guide system, the movable arms being mounted articulated so that the movement of the slide in one direction causes the movable arms to deploy while the movement of the slide in an opposite direction causes the movable arms to fold, the free ends of the movable arms delimiting an adjustable spacing section for the stretchable sleeve, between a minimum spacing section and a maximum spacing section; - a compressed air blowing circuit comprising conduits opening into the level of the free ends of the movable arms of the conformer.

[0013] Advantageously, the movable arms are acted upon by means of a spacing system configured to ensure the deployment and folding of the movable arms.

[0014] Advantageously, the slide guide system is mounted on the fixed support using a removable fixing system allowing the position of the shaper to be adjusted relative to the object's placement plane.

[0015] For example, the compressed air blowing circuit comprises a series of conduits each extending along the movable arms to open at the free end of the movable arms via a first end, these conduits having, opposite the first ends, second ends communicating with a distribution manifold connected to a compressed air supply conduit. Brief description of the drawings

[0016] [Fig.l] [Fig.l] is a simplified general perspective of an exemplary embodiment of an installation according to the invention for placing a stretchable sleeve around an object.

[0017] [Fig.2] [Fig.2] is a larger-scale perspective of an exemplary embodiment of the conformer implemented in the installation according to the invention.

[0018] [Fig.3] [Fig.3] is a schematic diagram in elevation of an exemplary embodiment of the conformer implemented in the installation according to the invention.

[0019] [Fig.4] [Fig.4] is a side view illustrating the installation in the ready position for sleeved an object.

[0020] [Fig.5] [Fig.5] is a profile view illustrating the positioning of the conformer adapted to the size of the object to be sleeved.

[0021] [Fig.6] [Fig.6] is a side view illustrating the creation of an air cushion at the free ends of the arms of the conformer when placing a sleeve on the conformer.

[0022] [Fig.7] [Fig.7] is a side view of a detail of the conformer illustrating the blowing of pressurized air at the free ends of the conformer arms to create a localized air cushion.

[0023] [Fig.8] [Fig.8] is a side view illustrating the installation after placing a sleeve on the conformer. Description of the embodiments

[0024] The subject of the invention relates to an installation 1 for placing a stretchable labeling sleeve 2 around an object 3 of any kind, such as for example a cylindrical container like a can, a bottle or a barrel. Conventionally, the elastic property of the sleeve 2 is used so that the sleeve 2 can, by stretching, be placed around the object 3. Each object 3 thus has a 3s inlet section corresponding to the part of the object from which the sleeve is placed around the object.

[0025] The installation 1 comprises a fixed support or frame 5 arranged to present a tray or a receiving table 6 for an object 3. The tray or the receiving table 6 is adapted to delimit a laying plane 6a for the object 3, configured to allow the object to be held in position during the operation of laying the sleeve around the object.

[0026] The installation 1 also comprises a shaper 8 supported by the fixed support 5 to be positioned above the laying plane 6a. The shaper 8 comprises movable arms 9 distributed angularly along the circumference of a slider 11 guided in vertical sliding on a guide system 12. In the example illustrated, the slider 11 is in the form of a ring slidably mounted on a rod 12a forming part of the guide system 12 and extending along the vertical axis X. As will be described more precisely in the remainder of the description, the movement of the slider 11 in one direction causes the movable arms 9 to deploy while the movement of the slider 11 in an opposite direction causes the movable arms 9 to fold back.

[0027] The movable arms 9 are for example each made by an elongated flat element of rectangular shape, having a first end 9a mounted in pivot connection along a horizontal axis 13. The axes 13 of the movable arms 9 are distributed according to a cross section of the slide which is taken perpendicular to the vertical axis X so that the movable arms cause the shaper to open and close like an umbrella. For example, each axis 13 is carried by a branch 11a extending radially from the slide 11. It should be noted that a part of the slide 11 extends above the axes 13 so as to be able to constitute a gripping zone of the slide.

[0028] Each movable arm 9 has a second end 9b, called the free end, opposite the first end 9a. The movable arms 9 all have the same length so that the free ends 9b of the movable arms 9 are all located in a section perpendicular to the vertical axis X. A stretchable sleeve 2 is intended to be placed around the shaper 8 so that the free ends 9b of the movable arms come into contact with the internal face of the stretchable sleeve to stretch it. The free ends 9b of the movable arms thus together delimit an adjustable spacing section for the stretchable sleeve, between a minimum spacing section and a maximum spacing section, depending on the degree of pivoting of the movable arms 9. In the example illustrated, the movable arms 9 are eight in number but of course the shaper can have a different number of movable arms.Generally speaking, the number of movable arms 9 is chosen according to the size and the more or less complex shape of the object 2 to be sleeved. It . There is a priori no limit to the number of movable arms 9 to be implemented to ensure this spacing function. A minimum of two movable arms can be considered if the shape of these movable arms is adapted to the object 3. In the example illustrated, the movable arms 9 are flat but it may be planned to produce the movable arms 9 with a curved shape to adapt to the cylindrical shape of the object 3.

[0029] According to an advantageous embodiment characteristic, the movable arms 9 are acted upon by means of a spacing system 15 configured to ensure the deployment and folding of the movable arms 9. In the embodiment illustrated in the drawings, the movable arms 9 are mounted articulated on the guide system 12 using the spacing system 15 comprising connecting rods 15a in a number equal to the number of movable arms 9. As is more precisely shown in [Fig. 3], the ends of each connecting rod 15a are mounted in pivot connection along a horizontal axis 15b on the one hand with a movable arm 9 and on the other hand, with a branch 12b extending radially from the free end of the rod 12a.

[0030] In the illustrated example, the movable arms 9 are mounted articulated on the slide 11 and the guide system 12 so that the movement of the slide ensures the deployment and folding of the movable arms. Thus, the downward sliding of the slide 11 causes the deployment of the movable arms 9 while the upward movement of the slide 11 leads to the folding of the movable arms 9. According to an exemplary embodiment, the slide 11 is moved manually. According to another exemplary embodiment, the slide 11 is moved using a linear actuator. In the same direction, the movable arms 9 are moved in the illustrated example, using the connecting rod spacing system 15a but it is clear that the movable arms can be moved differently using for example a rack system.

[0031] According to an advantageous embodiment characteristic, the guide system 12 of the slide 11 is mounted on the fixed support 5 using a removable fixing system 17 making it possible to adjust the position of the shaper 8 relative to the laying plane 6a of the object 3. In the example illustrated, the removable fixing system 17 comprises a clamping screw 17a cooperating with the rod 12a sliding in a passage 5c provided in a bracket 5d of the fixed support 5. Of course, the removable fixing system 17 can be produced in a different manner. For example, the rod 12a is equipped with a handle 12p facilitating the vertical movement of the shaper 8.

[0032] According to another characteristic of the invention, the installation 1 also comprises a blowing circuit 20 for compressed or pressurized air comprising conduits 20a opening at the free ends 9b of the movable arms 9 of the shaper 8. This blowing circuit 20 is configured to create an air cushion 22 located at the entry section of the object 3, between the stretchable sleeve 2 and the object 3, for allow the sleeving operation to be carried out.

[0033] According to an advantageous embodiment characteristic, the air blowing circuit 20 comprises a series of conduits 20a each extending along a movable arm to open at the free end 9b of the movable arms by a first end 20b. As is more precisely shown in Figures 6 and 7, these conduits 20a are mounted on the internal face of each of the movable arms 9 to extend along the movable arms to the free end 9b of the movable arms 9. More precisely, as the free end 9b of the movable arms is in contact with the object 2, these conduits 20a are slightly set back from the free end 9b of the movable arms 9, for example by a few mm. Preferably, all the movable arms 9 are provided with conduits 20a for conveying the pressurized air.

[0034] Advantageously, the first ends 20b of the conduits 20a are configured to blow the air towards the point of contact between the movable arms 9 and the object 2, that is to say in the extension of the free ends of the movable arms 9 to create the air cushion between the stretchable sleeve 2 and the object 3. The first ends 20b of the conduits 20a can thus be oriented towards the outside of the former 8 or be equipped with outlet nozzles directing the flow towards the outside of the former.

[0035] The conduits 20a have, opposite the first ends 20b, second ends 20c communicating with a distribution manifold (not shown), connected to a pressurized air supply conduit 20d. Thus, all the conduits 20a are supplied with pressurized air during the sleeving operation to create an air cushion 22 to assist with sleeving.

[0036] The implementation of the installation 1 described above allows the implementation of a sleeving method which follows directly from the description above. The method according to the invention aims to place around an object 3, a stretchable sleeve 8, using a shaper with movable arms 9 delimiting by their free ends 9b, an adjustable spacing section for the stretchable sleeve. The method according to the invention comprises the following steps: - equip the conformer 8 with a stretchable sleeve 2; - adjusting the spacing section of the conformer 8 to an entry section 3s of the object 3 corresponding to the part of the object from which the stretchable sleeve is sleeved; - bringing the free ends 9b of the movable arms 9 of the conformer into contact with the input section 3s of the object; - bringing the stretchable sleeve 2 into contact with the spacer section of the conformer; - blowing pressurized air at the free ends 9b of the movable arms 9 of the conformer to create a localized air cushion at the section entry of the object, between the stretchable sleeve 2 and the object 3; - ensure the gripping of the stretchable sleeve 2 in its part located at the level of the air cushion; - and exert a tensile force on the stretchable sleeve to translate it until the stretchable sleeve 2 is sleeving around the object 3.

[0037] The method described above allows the installation of stretchable sleeves 2 using a shaper 8 of adjustable size for various types of objects 3, without multiplying the number of tools and without excessively stretching the sleeve 2. The pressurized air sent by the shaper 8 allows the stretchable sleeve 2 to be locally deformed, facilitating its gripping and its movement when it is installed around the object.

[0038] According to a characteristic of the invention, the spacing section of the former 8 is adjusted by unfolding the movable arms 9 between a minimum spacing section shown in [Fig.4] and a maximum spacing section. Typically, the spacing section of the former 8 can vary between 80 cm and 170 cm. In other words, the former 8 can place stretchable sleeves around cylindrical objects having diameters greater than 80 cm and less than 170 cm for example, knowing that these diameters can change depending on the elasticity of the material chosen for the stretchable sleeve 2.

[0039] According to an advantageous characteristic, the method according to the invention aims to implement a phase of adjustment of the conformer 8 for a format of objects 3. Thus, when this adjustment phase has been carried out, the conformer 8 can be used successively for all the objects 3 having the same format. This adjustment phase comprises the following steps: - provide a shaper 8 comprising movable arms 9 distributed angularly along the circumference of a slide 11 guided in vertical sliding on a guide system 12, the movable arms 9 being mounted articulated so that the movement of the slide 11 in one direction causes the movable arms 9 to deploy while the movement of the slide in an opposite direction causes the movable arms 9 to fold back; - move the slide 11 to adjust the spacing section of the conformer to the entry section 3s of the object; - moving the guide system 12 of the slide in order to bring the free ends 9b of the movable arms of the shaper into contact with the entry section of the object while the spacing section of the shaper corresponds to the entry section of the object; - and lock the slide guide system 12 in position.

[0040] At the start of this adjustment phase, an object 3 to be sleeved is positioned on the laying plane 6a to be located below the shaper 8 ([Fig.4]). The object 3 is positioned so that its entry section 3s corresponding to the part of the object from which the sleeve is sleeved, is positioned upwards towards the shaper 8. In this position, the movable arms 9 are folded, that is to say extend substantially parallel to the vertical axis X ([Fig.4]). For the adjustment phase, the movable arms 9 are deployed so that the free ends 9b of the movable arms 9 delimit a spacing section corresponding to the entry section 3s of the object 3. For this purpose, the slide 11 is moved in translation to ensure the opening of the movable arms 9. In addition, the shaper 8 is moved vertically relative to the object, via the guide system 12 of the slide, so that the free ends 9b of the movable arms 9 come to bear on the object 3 ([Fig.5]). For this purpose, the screw 17a of the removable fixing system 17 is loosened to allow the lowering of the conformer 8.When the movable arms 9 are resting on the object 3, the screw 17a is tightened to lock the rod 12a which supports the shaper 8 in position. In this position, the free ends 9b of the movable arms 9 are flush with the outside diameter of the object 3. It should be noted that in this position, the movement of the slide 11 is limited downwards by the presence of the object 3 under the movable arms 9. Once the adjustment has been made, the slide 11 can be moved upwards in order to release the object 3.

[0041] After this adjustment phase, each object 3 of the same format is sleeved by implementing the following steps: - a stretchable sleeve 2 is slipped onto the former 8; - an object to be sleeved 3 is positioned on the laying plane 6a; - the slide 11 is moved in order to bring the free ends 9a of the movable arms 9 of the shaper 8 into contact with the entry section of the object 3. In this position of support of the movable arms 9 on the object 3, it should be noted that the spacing section of the shaper 8 corresponds to the entry section of the object following the adjustment phase; - the stretchable sleeve 2 is moved to the inlet section 3s of the object 3; - pressurized air is blown at the free ends 9b of the arms of the shaper to create a localized air cushion 22; - a tensile force is applied to the stretchable sleeve 2 in its part located at the level of the air cushion to translate it until the stretchable sleeve is sleeving around the object; - at the end of the sleeving operation, the pressurized air is preferably cut off; - the slide 11 is moved to ensure the folding of the movable arms 9; - the sleeved object 3 is removed; - and a new stretchable sleeve 2 is slipped onto the conformer 8 for its installation on a new object.

[0042] Thus, when the former 8 is in its folded position ([Fig.4]), a stretchable sleeve 2 can be slipped around the former 8. After positioning an object to be sleeved 3 on the laying plane 6a, the slider 11 is moved in order to bring the free ends 9a of the movable arms 9 of the former 8 into contact with the entry section of the object 3 ([Fig.5]). The movement of the slider 11 leads to the deployment of the movable arms 9 whose spacing corresponds to the entry section of the object. The positioning of the movable arms 9 is automatic and results from the adjustment phase. The stretchable sleeve 2 is moved to the entry section 3s of the object 3 and pressurized air is blown at the free ends 9b of the movable arms to create a localized air cushion 22 (Figures 6 and 7). The air is blown towards the point of contact between the object and the movable arms, in line with the free ends 9b of the movable arms.This air cushion 22 allows the sleeve to be stretched to facilitate its installation. A tensile force represented by the arrow F in [Fig.7] is applied to the stretchable sleeve 2 in its part located at the level of the air cushion. This tensile force is applied to the sleeve to translate it until the object is completely sleeved.

[0043] Once the sleeving is completed, the pressurized air is cut off. The slide 11 is raised, which causes the movable arms 9 to fold back as illustrated in [Fig.8]. The former 8 and in particular the free ends of the movable arms 9 are freed from the sleeved object 3 which can thus be removed. A new stretchable sleeve 2 can be slipped onto the former 8 for placement on a new object.

Claims

Claims

1. Method for placing a stretchable sleeve (2) around an object (3), using a former (8) with movable arms (9) delimiting by their free ends (9b), an adjustable spacing section for the stretchable sleeve, the method comprising the following steps: - equipping the former (8) with a stretchable sleeve (2); - adjusting the spacing section of the former (8) to an entry section of the object corresponding to the part of the object from which the stretchable sleeve is sleeved; - bringing the free ends (9b) of the movable arms (9) of the former into contact with the entry section of the object; - bringing the stretchable sleeve (2) into contact with the spacing section of the former; - blowing pressurized air at the free ends (9b) of the arms of the shaper (8) to create a localized air cushion at the entry section of the object, between the stretchable sleeve (2) and the object (3);- ensure the gripping of the stretchable sleeve (2) in its part located at the level of the air cushion; - and exert a tensile force on the stretchable sleeve (2) to translate it until the stretchable sleeve is sleeving around the object.;

2. Method according to claim 1 according to which after the sleeving operation, the free ends (9b) of the movable arms of the shaper (8) are released from the object (3) to ensure the removal of the sleeving object and the installation of a new object to be sleeving.

3. Method according to one of the preceding claims, wherein the spacing section of the conformer (8) is adjusted by unfolding the movable arms (9) between a minimum spacing section and a maximum spacing section.

4. Method according to one of the preceding claims, according to which an adjustment phase is carried out for a format of objects (3) comprising the following steps: - providing a shaper (8) comprising movable arms (9) distributed angularly according to the circumference of a slide (11) guided in vertical sliding on a guide system (12), the movable arms (9) being mounted articulated so that the movement of the slide (11) in one direction causes the deployment of the movable arms while the de- placing the slider, in an opposite direction, causes the movable arms to fold; - moving the slider (11) to adjust the spacing section of the conformer (8) to the entry section of the object; - moving the guide system (12) of the slider in order to bring the free ends (9b) of the movable arms (9) of the conformer into contact with the entry section of the object while the spacing section of the conformer corresponds to the entry section of the object; - and locking the guide system (12) of the slider (H) in position.

5. Method according to the preceding claim according to which after the adjustment phase, for each object (3) to be sleeved of the same format: - a stretchable sleeve (2) is slipped onto the former (8); - an object (3) to be sleeved is positioned; - the slide (11) is moved in order to bring the free ends (9b) of the movable arms of the former (8) into contact with the entry section of the object while the spacing section of the former corresponds to the entry section of the object; - the stretchable sleeve (2) is moved to the entry section of the object (3); - pressurized air is blown at the free ends (9b) of the movable arms (9) of the former to create the localized air cushion (22); - a tensile force is applied to the stretchable sleeve (2) in its part located at the air cushion to translate it until the stretchable sleeve is sleeved around the object;- the slide (11) is moved to ensure the folding of the movable arms (9); - the sleeved object is removed; - and a new stretchable sleeve (2) is slipped onto the former (8).;

6. Method according to one of the preceding claims, wherein the pressurized air is blown towards the extension of the free ends (9b) of the movable arms of the shaper (8) to create the air cushion.

7. Installation for placing around an object (3), a stretchable sleeve (2), comprising: - a fixed support (5) delimiting a placing plane (6a) for the object; - a shaper (8) supported by the fixed support (5) to be po- located above the laying plane, the shaper (8) comprising movable arms (9) distributed angularly according to the circumference of a slide (11) guided in vertical sliding on a guide system (12), the movable arms (9) being mounted articulated so that the movement of the slide (11) in one direction causes the movable arms (9) to be deployed while the movement of the slide in an opposite direction causes the movable arms (9) to be folded, the free ends (9b) of the movable arms delimiting an adjustable spacing section for the stretchable sleeve (2), between a minimum spacing section and a maximum spacing section; - a compressed air blowing circuit (20) comprising conduits (20a) opening at the free ends (9b) of the movable arms (9) of the shaper.

8. Installation according to claim 7 according to which the movable arms (9) are acted upon by means of a spacing system (15) configured to ensure the deployment and folding of the movable arms (9).

9. Installation according to one of claims 7 or 8 according to which the guide system (12) of the slide (11) is mounted on the fixed support using a removable fixing system (17) making it possible to adjust the position of the shaper (8) relative to the laying plane (6a) of the object.

10. Installation according to one of claims 7 to 9 according to which the compressed air blowing circuit (20) comprises a series of conduits (20a) each extending along the movable arms (9) to open at the free end (9b) of the movable arms by a first end, these conduits (20a) having, opposite the first ends, second ends communicating with a distribution manifold connected to a compressed air supply conduit (20).

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