EP2701856A1

EP2701856A1 - A system for removing self-adhesive labels

Info

Publication number: EP2701856A1
Application number: EP11728412.5A
Authority: EP
Inventors: Mauro COLOMBINI; Damiano RESTELLI
Original assignee: Ates Impianti Srl
Current assignee: Ates Impianti Srl
Priority date: 2011-04-28
Filing date: 2011-05-09
Publication date: 2014-03-05
Anticipated expiration: 2031-05-09
Also published as: WO2012147110A1; RU2013151658A; ES2537447T3; EP2701856B1; ITMI20110704A1; RU2563169C2

Abstract

A system for removing labels applied to reusable containers comprises a support plate for the container, a double-acting pneumatic cylinder which presses the container against the support plate in a manner so as to maintain the container integral with the latter, and a motorized brush with rotary roller that, by means of a second double-acting pneumatic cylinder, is brought into contact with the container in order to scrape off the label. The system also comprises an electric motor by means of which, through suitable coupling mechanisms, the support plate of the container is made to rotate around an axis parallel to the axis of the brush or translate in a reciprocating manner orthogonal to the axis of the brush, depending on whether the container whose the label is to be removed is cylindrical, such as a bottle, or parallelepiped, like a tin. A third double-acting pneumatic cylinder allows translating the roller brush in a reciprocating manner, parallel to its axis, in order to allow the removal of labels of greater height than the height of the brush. Cold water is sprayed in the contact zone between the brush and the container in order to lubricate, prevent overheating and facilitate the elimination of the removed label fragments.

Description

A system for removing self-adhesive labels

Field. of application of the invention

The present invention refers to the field of machinery for cleaning containers in general, aimed for the reuse thereof, and more precisely refers to a system for removing self-adhesive labels.

Review of the prior art

As is known, most of the products present on the market are sold in suitable containers made of different materials, such as glass, plastic, aluminum, paper, wood, etc. Once product use has ended, or in any case once the product has been definitively removed from its own container, the latter is usually eliminated as recyclable waste. As an alternative to the elimination, the surplus containers can be reused at home, as occurs for example for glass jars, or at the industrial level by container manufacturers or by the companies who make the products that the containers are intended to contain, as occurs for example for glass bot- ties in the field of wine and mineral water. Glass is indeed an extremely rigid material, easy to sterilize, and this ensures that glass containers and bottles in particular can be reused many times before being recycled, with a great reduction of costs and environmental impact. When a product is piaced on the market in a bottle, a label is affixed thereon which allows identifying the manufacturer and reports the characteristics of the contained product. The labels on the bottles are usually made of paper and can be self-adhesive or applied to the bottles by means of separate gluing. The presence of the labels represents an ob- stacle to the reuse of bottles, since they must be removed before a bottle can be newly used. In order to remove non-self-adhesive labels, it is necessary to immerse the bottles in a hot bath of caustic soda and leave it immersed for a ' time period sufficient to dissolve the glue. The process of removing seif- adhesive labels instead requires longer times and occurs under cold conditions, using specific solvents or via the immersion of the bottles in hot baths containing suitable chemical agents. Even if labeling by means of self-adhesive labels is faster and less expensive with respect to the application of the non-self- adhesive labels, there are enormous disadvantages when cleaning the bottles for reuse. Current processes for removing self-adhesive labels do not in fact give optimal results, since they provide for a high percentage of waste and require not only long times but also the use of a considerable quantity of thermal energy (like the non-self-adhesive label removal processes) and polluting chemical agents or cancerogenic solvents. Faced with all of the above, companies of- ten give up the thought of reusing containers, with the consequent destruction of the same.

Objects of the invention

Therefore, the object of the present invention is to overcome the aforesaid drawbacks and indicate a system for the quick, cold removal of self-adhesive and non-self-adhesive labels from generic containers that does not require the use of any solvent or chemical agent.

Summary of the invention

In order to attain such objects, the present invention has as object a system for removing labels applied to reusable containers, wherein according to the inven- tion it includes:

- means for supporting a container;

- ; reversible means for fixing the container to the support means;

! - a motorized brush with rotary roller positionable with its brushing profile against one said label;

- means for moving the container capable of imparting a different speed to said support means with respect to the tangential speed of the brushing profile;

- means for spraying a water-based lubricant liquid on the surfaces in contact during the brushing, as described in claim 1.

Further characteristics of the present invention deemed innovative are described in the dependent claims.

According to one aspect of the invention, said reversible fixing means are pres- sure means adapted to exert a pressure on the container against the support means. Advantageously, said pressure means comprise a double-acting pneumatic cylinder, or a cylinder containing a piston thrust by a helical spring.

According to one aspect of the invention, the movement means for the container are capable of imparting a continuous rotation to the support means in the direction opposite the rotation direction of the brushing profile. Such solution is applicable to cylindrical containers, or to parallelepiped containers with labels that are extended on contiguous faces due to the deformation of the fibers of the brush at the corners.

According to one aspect of the invention, the movement means for the con- tainer are capable of imparting a continuous rotation to the support means in the same rotation direction as that of the brushing profile. Also this solution is applicable to the cylinder containers, or to parallelepiped containers with labels that are extended on contiguous faces due to the deformation of the fibers of the brush at the corners.

According to one aspect of the invention, said movement means capable of imparting a rotation comprise an electric motor controlled by means of an inverter. According to one aspect of the invention, the movement means for the container are capable of imparting a reciprocating translation to the support means, transverse to the roller brush. Such solution is applicable to parallelepiped con- tainers.

According to one aspect of the invention, said pressure means include an axial bearing integral with the head of the piston.

According to one aspect: of the invention, said pressure means include a recir- culating-ball linear bearing integral with the head of the piston.

According to one aspect of the invention, the motorized brush roller is connected to second movement means capable of imparting reciprocating translations along the longitudinal axis of the brush roller, for a brush roller shorter than the label height.

According to one aspect of the invention, the movement means for the container are capable of imparting reciprocating translations to the container which are parallel to the brushing profile, for a brush roller shorter than the label height.

According to one aspect of the invention, the label removal system includes means for translating the roller brush in the direction of the container, in order to scale the contact pressure.

Advantages of the invention

; The system that is the object of the invention is capable of removing, under cold conditions, labels made of paper, cardboard, plastic or which are metalized, that are self-adhesive and non-self-adhesive, of any shape and finish, in short times and with a low consumption of current and water, without having to use additives or solvents. The spray of water-based liquid lubricant avoids overheating the container on which the label is applied, and facilitates the elimination of the removed label parts, in a manner so as to leave the container perfectly clean and without any scratch. The system that is the object of the invention is capable of functioning with all the glues commonly used for the application of labels, such as casein, modified starch, dextrin, modified dextrin, cellulose, thermofusi- ble flue, etc., and independent of the position of the label on the container. It is necessary to simply tighten the container in a manner so that the label is reachable by the roller brush.

The system can brush containers made of glass, plastic (PVC, PET, PP and PC), aluminum or iron without these being minimally ruined during brushing, ensuring that none of the cleaned containers will have to be discarded and the immediate reuse of the container at the end of the label removal process. Even if the containers best suited for being brushed with the system that is the object of the invention are those in which the label is applied on a cylindrical surface, like bottles, jars and cans, the flexibility of the metal or plastic fibers of the roller brush together with the possibility of reciprocating movement of the container with respect to the brush ensure the functioning of the system even for containers with flat faces or irregular form, like small bottles, drums, cases and boxes. This allows employing the present label removal system not only in the food or drink field but also in the chemical, pharmaceutical and cosmetic fields, among others.

Brief description of the figures

Further objects and advantages of the present invention will be clear from the detailed description that follows of an embodiment of the same and from the enclosed drawings given as a merely a non-limiting example, wherein:

- Figure 1 shows a front view of the system for removing labels according to the invention, in particular for cylindrical containers;

- Figure 2 shows a schematization of the movement mechanism for the containers of the system of figure 1 ;

- Figure 3 shows a top view of the system of figure 1 ;

- Figure 4 shows the system of figure 1 employed for the removal of labels from containers of parallelepiped shape;

- Figure 5 is the top view of the system of figure 4.

Detailed description of several preferred embodiments of the invention

In the following description, equivalent elements which appear in different figures can be indicated with the same symbols. In the illustration of one figure, it is possible that reference will be made to elements not expressly indicated in that figure but in preceding figures. The scale and proportions of the various depicted elements do not necessarily correspond to the actual scale/proportions.

Figure 1 shows a system for removing a label 1 applied to a reusable container, in the current case a wine bottle BT with cylindrical shape, but the same system is also capable of removing labels from containers with parallelepiped shape LT (figure 4). The system comprises a base 2 from which, on the right side in the figure, a pillar 3 isi extended upward for the support of a C-shaped longitudinal section frame 4 which sustains and encloses the movement mechanism for the containers. From the base 2, on the left side in the figure, a double-acting pneumatic cylinder 5 is extended upward, in retracted configuration of the piston 5a whose end is rigidly connected to a second frame 6, it too with C-shaped longitudinal section, which sustains and encloses the movement mechanism for a roller brush 7 for the removal of the label 1.

The roller brush 7 is crossed by the drive shaft 8 of an electric motor 9 fixed to the upper part of the frame 6 by means of a bracket 10 integral with a slide 11 which maintains the shaft 8 of the motor 9 vertical. The slide 11 allows the translation of the motor 9 in a horizontal plane. The bracket 10 is close to the end of the slide 11 closer to the drive shaft 8. The slide comprises a track 11a integral with the frame 6 in which a sliding block 11b integral with the bracket 10 can slide. The frame 6 and the track 11a have a recess 6a in order to avoid interference with the drive shaft 8 during the latter's translation. The bracket 10 is connected to the sliding block 11b by means of a coupling system 17 comprising two short helical springs 18, thus creating one degree of freedom for absorbing possible longitudinal oscillations of the drive shaft 8 which could especially occur at the time of motor 9 ignition, thus avoiding dangerous deformations. Inside the springs 18, a pin 18a is placed which crosses the bracket 10, maintaining the vertical alignment of the springs. The roller brush 7 is integral with the drive shaft 8 in the lower part of the latter. The distal end of the shaft 8 is inserted in a conical roller bearing 12 included in a block 13 integral with the end of a piston 14 of a second double-acting pneumatic cylinder 15, fixed to the lower part of the frame 6; the small 'cloud-like' excerpt in the figure illustrates an enlargement of the connection. The piston 14 is arranged orthogonally to the drive shaft 8. The block 13 lies on the sliding block 16a of a second slide 16 integral with the frame 6. The block 13 is integral with the sliding block 16a. In the configuration shown in the figure, the piston 14 has reached its maximum elongation. The conical roller bearing 12 reduces the radial friction on the drive shaft 8, otherwise caused by the thrust exerted by the piston 14 against the block 13, so that the brush 7 can exert the necessary pressure against the bottle BT. The conical roller bearing 12 also absorbs the axial thrust caused by the contraction of the springs 18 at the time of motor 9 ignition; in order to facilitate this, the sliding block 16a has a notch in which the end of the drive shaft 8 can pene- trate.

The height of the roller brush 7 is about the height of the 75 cl glass wine bottles, exceeding therefore the body of the bottle. In the configuration shown in the figures, the length of the drive shaft is about two and a half times the height of the brush 7.

A casing 20 is fixed to the lower part of the frame 4 for the containment of the rotation mechanism for a plate 23 on which the container BT lies. The plate 23 lies on a plate 21 equipped with two fitted seats, in which two complementary reliefs of the plate 23 can translate in a slidable manner; such plate 23 is actuated by the slider of a device 31 , to which is rigidly connected. The device 31 is driven by a short transmission shaft 22 exiting from the casing 20. The reciprocating translation of the slide plate 23 occurs in a direction orthogonal to the shaft 8 of the motor 9 and to the piston 14 of the cylinder 15; such translation does not affect the cylindrical container BT but only containers with parallelepiped shape, The container BT lying on the slide plate 23 is arranged on the rotation axis of the plate 21. In the configuration of complete elongation of the piston 14, the brush 7 is in contact with the surface of the container BT and is there- fore capable of scraping off the label 1. The container BT is pressed against the slide plate 23 by the head 26 of a piston 24 vertically exiting from a double- acting pneumatic cylinder 25 fixed to the upper wall of the frame 4. The piston 24 is also aligned with the rotation axis of the plate 21. The head 26 comprises the sequential connection with a slide 28 and with an axial bearing 27 lying on the container, whether this is cylindrical BT or parallelepiped LT, during the application of the pressure. The sequential connection 28, 27 decouples the piston 24 from the rotary motion imparted to the container with cylindrical shape BT or from the rotary motion imparted to the container with parallelepiped shape LT. As an alternative to the slide 28 it is possible to connect the end of the piston 24 to a recirculating-ball linear bearing. A small tube 38 sprays a water-based lubricant liquid in the contact zone between the roller brush 7 and the container BT The liquid can also be water at the same pressure as domestic piping.

Figure 2 is a schematization of the movement mechanism for the slide p!ate 23 inside the casing 20. With reference to the figure, the presence is noted of a second electric motor 29 whose drive shaft 30 is orthogonal to the piston 24 of the cylinder 25 and is coupled to the plate 21 by means of a pair of bevel gears 32 and 33 and an interposed clutch 39, activated or deactivated by the operator with the change of shape of the container from cylindrical to parallelepiped or vice versa. The clutch 39 couples the shaft of the bevel gear 33 with a short transmission shaft 41 integral with the plate 21 at the center thereof. The drive shaft 30 crosses the bevel gear 32 and engages a second clutch 34 identical to the clutch 39 and synchronously controlled therewith. Exiting from the clutch 34 is the short transmission shaft 22, which controls the movement device 31. The !atter is an crank and slotted link comprising a ram 35 rigidly connected to one end of a rod 36 whose other end is rigidly connected to the outer rim of a radial ball bearing 37, whose inner rim is integral with the slide plate 23. The ram 35 translates orthogonally to the piston 24 of the cylinder 25 and to the piston 14 of the cylinder 15.

Figure 3 shows a top view of the roller brush 7 in contact with the container BT of figure 1 in order to scrape off the label 1. In the figure configuration, the crank and slotted link 31 is deactivated, the plate 21 is rotated by the motor 29 and the rotation direction of the roller brush 7 is equivalent to that of the slide plate 23, such that the tangential speeds of the roller brush 7 and of the container BT at the contact zone are opposing.

Figure 4 shows the system of figure 1 used for scraping off a self-adhesive label 40 glued to a parallelepiped container LT. In the configuration of figure 4, the container LT positioned on the slide plate 23 has the maximum size allowed by the removal system. It is possible to note in the figure that the container LT nearly completely occupies the base of the slide plate 23, and the piston 24 of the cylinder 25 is retracted the difference in height between the containers LT and BT. The piston 14 of the cylinder 15 is retracted the difference between the half width of the container LT and the radius of the container BT. Since the height of the roller brush 7 is less than the height of the label 40, the cylinder 5 is controlled in order to make the frame 6 complete a reciprocating translation. In the configuration shown in the figure, the piston 5a of the cylinder 5 is nearly completely elongated in order to scrape off the label 40, the removal of the label 40 in the lower part having been completed.

Figure 5 shows a top view of the roller brush 7 in contact with container LT of figure 4. In the configuration visible in the figure, the crank and slotted link 31 is activated while the rotation of the plate 21 is deactivated.

Even if not shown in the figures, it is entirely evident that the label removal system illustrated therein comprises a compressor for actuating the pneumatic cylinders 5, 15, 25 and a microprocessor control system equipped with control panel with buttons and signal lamps available to the operator.

With regard to the illustration of the functioning, the removal of the label 1 from the bottle BT is initially considered. The starting condition is that in which the piston 5a of the cylinder 5, the piston 14 of the cylinder 15 and the piston 24 of the cylinder 25 are completely retracted, the electric motors 9 and 29 are off, the clutches 34 and 39 are both disengaged, the water pump is off, and the guides of the slide plate 23 are arranged parallel to the translation direction of the ram 35. The operator positions the bottle BT with the base centered in the center of the slide plate 23 and actuates the cylinder 25 until a sensor (not shown) signals the attainment of desired pressure of the piston 26 head against the bottle BT and the elongation is stopped. Since the roller brush 7 is aligned with the base of the bottle BT and the label 1 has lower height than the brushing profile, the cylinder 5 is not actuated. The cylinder 15 is actuated in order to bring the roller brush 7 in contact with the label 1 of the bottle BT until a second sensor (not shown) signals the contact that occurred between the roller brush 7 and the bottle BT, with a slight pressure, and the elongation is stopped. At this point, the following are simultaneously actuated: the water pump, the motor 9 for controlling the rotation of the roller brush 7, the motor 29 and the clutch 39 for coupling the shaft exiting from the bevel gear 33 with the drive shaft 41 and controlling the rotation of the bottle BT in the same rotation direction as the shaft 8 of the motor 9 or in opposite direction but at a different speed. In particular, the motor 9 is controlled by means of an inverter in order to establish an angular speed of the shaft 8 equal to 1400 rpm (revolutions per minute) in the ro- tation of a brush 7 of metal type. The motor 29 for moving the bottle BT is also controlled by means of an inverter in order to establish an angular speed of the drive shaft 30 of 800 rpm. Water is sprayed from the tube 38, such water at ambient temperature and at a pressure of 1.5 bar in order to obtain a flow rate of 2- 3 liters per minute. The brush 7 is pressed against the bottle BT for 4-5 sec- onds, such time on average sufficient for removing the label 1.

Once the removal of the label 1 has been terminated, the motors 9 and 29 are turned off, the piston 24 is retracted a sufficient amount for removing the bottle BT and inserting another bottle of the same batch whose label is to be removed. ¾ 5 The above-described process is repeated for all the bottles having the same shape and size.

Our discussion will now shift from the removal of labels 1 from bottles BT to the removal of labels 40 from parallelepiped containers LT. For such purpose, it is convenient to bring the system back to the above-illustrated initial condition.

10 The operator positions the container LT with the base centered in the center of i the slide plate 23 and actuates the cylinder 25 until the sensor (not shown) sig- t nals the attainment of the desired pressure of the head 26 of the piston 24 against the container LT and the elongation is stopped. The cylinder 15 is actuated in order to bring the roller brush 7 in contact with the label 40 of the con-

15 tainer LT until the second sensor signals that the contact has occurred between the roller brush 7 and the container LT, with a slight pressure, and the elongation is stopped. At this point, the following are simultaneously actuated: the water pump, the motor 9 for controlling the rotation of the roller brush 7, the motor 29 and the clutch 34 for coupling the drive shaft 30 which crosses the bevel

20 gear 32 to the transmission shaft 22 and activating the crank and slotted link 31 , controlling the reciprocating translation of the slide plate 23 and the container LT therewith. In the upper part facing the container LT, the slide 28 included in the head 26 decouples the piston 24 from the translation of the slide plate 23. Since the roller brush 7 is aligned with the base of the container LT and the la-

25 bel 40 has greater height than the brushing profile, it is necessary to actuate the cylinder 5 in order to completely remove the label 40. Two modes can be employed by the operator. According to a first mode, the roller brush 7 completes slow, reciprocating translations. In accordance with the second mode, the piston 5a is slowly elongated in a manner so as to progressively remove the label 40

30 during elongation.

In the case in which the label is affixed on contiguous faces of a parallelepiped container LT, once the label is removed from a first face it is necessary to stop the system, slightly retract the piston 24 and rotate the container 90° on the slide plate 23 - in a manner such that the face on which the label continues is opposite the roller brush 7 - and activate a new removal process.

On the basis of the description provided for a preferred embodiment, it is obvi- ous that any changes can be introduced by the man skilled in the art without departing from the protective scope of the invention, as results from the following claims.

Claims

1. A system for removing labels (1 , 40) applied to reusable containers (BT, LT), characterized in that it includes:

- means (21 , 23) for supporting a container (BT, LT);

- reversible means for fixing (24, 25, 26) the container (BT, LT) to the support means (21 , 23);

- a motorized brush with rotary roller (7, 8, 9) positionable with its brushing profile against one said label (1 , 40);

- means (29, 30, 32, 33, 34, 39, 41 , 22, 31 , 35, 36, 37) for moving the con- ta!ner (BT, LT) capable of imparting a different speed to said support means

(2 , 23) with respect to the tangential speed of the brushing profile;

- means for spraying (38) a water-based lubricant liquid on the surfaces in contact during brushing.

2. The label removal system according to claim 1 , characterized in that said reversible fixing means are pressure means (24, 25, 26) adapted to exert a pressure on the container (BT, LT) against said support means (23).

3. The label removal system according to claim 2, characterized in that said pressure means comprise a double-acting pneumatic cylinder (25, 24), or a cylinder containing a piston (24) thrust by a helical spring.

4. The label removal system according to claim 1 , characterized in that said means (29, 30, 32, 33, 39, 41) for moving the container (BT) are capable of imparting a continuous rotation to said support means (21 , 23) in the opposite direction with respect to the rotation direction of the brushing profile in order to remove the labels (1) from containers with cylindrical shape (BT).

5. The label removal system according to claim 1 , characterized in that the means (29, 30, 32, 33, 39, 41) for moving the container (BT) are capable of i imparting a continuous rotation to the support means (21 , 23) in the same rotation direction as the brushing profile in order to remove labels (1) from containers with cylindrical shape (BT).

6. The label removal system according to claim 1 , characterized in that said means (29, 30, 34, 22, 31 , 35, 36, 37) for moving the container (LT) are capable of imparting a reciprocating translation to the support means (23), transverse to the roller brush (7) in order to remove the labels (40) from containers with parallelepiped shape (LT).

7. The label removal system according to claim 1 , characterized in that ; said means for moving the container (BT, LT) comprise an electric motor (29) f whose drive shaft (30) is selectively coupled, by means of electrically -controlled clutch means (39, 34), to a rotation mechanism (32, 33, 41) or to a translation mechanism (22, 31 , 35, 36, 37) for said support means (21 , 23).

8. The label removal system according to claim 3, characterized in that the head (26) of said piston (24) belonging to said pressure means includes the sequential connection with a slide (28) and with an axial bearing (27) lying on the container (BT, LT) during the application of the pressure, said sequential • ΐ connection (28, 27) decoupling the piston (24) from the rotary motion imparted to a container with cylindrical shape (BT) or from the translation motion imparted to a container with parallelepiped shape (LT).

9. The label removal system according to claim 8, characterized in that a recirculating-ball linear bearing is included in the head (26) of said piston (24) as an alternative to the slide (28).

10. The label removal system according to claim 1 , characterized in that the motorized brush with rotary roller (7) is connected to second movement means (5, 5a) capable of imparting reciprocating translations along the longitudinal axis of the brush.

11. The label removal system according to claim 1 , characterized in that it includes means (14, 15) for translating the roller brush (7) in the direction of the container (BT, LT) in order to scale the contact pressure.

12. The label removal system according to claim 1 , characterized in that said means for moving the container are capable of imparting reciprocating s translations to the container (BT, LT) that are parallel to the brushing profile.