PACKAGING ROBOT AND METHOD USED TO CARRY OUT A PACKAGING PROCESS

Abstract

Disclosed is a packaging robot for articles such as beverage containers or the like. The packaging robot comprises a bridge (3) as well as at least two tool holders (5) arranged at the bridge (3), wherein the at least two tool holders (5) arranged on the bridge (3) are each movable along the bridge (3) and can each accommodate a tool head (7). It is provided that at least one tool holder (5) of the at least two tool holders (5) arranged at the bridge (3) is optionally able to be equipped with a particular tool head (7) adapted to the particular packaging process to be performed. It is also provided that the at least one tool holder (5) of the at least two tool holders (5) can switch into a standby mode while remaining at the bridge (3) if the particular packaging process to be performed by the packaging robot does not require the at least one tool holder (5) to be equipped with a tool head (7).

Claims

1. A packaging robot (15, 16, 17) for articles, comprising: a bridge (3) and at least two tool holders (5) arranged at the bridge (3), wherein the at least two tool holders (5) are each movable along the bridge (3) and can each accommodate a tool head (7), wherein: at least one tool holder (5) of the at least two tool holders (5) is optionally able to be equipped with a particular tool head (7) adapted to the particular packaging process to be performed, and wherein the at least one tool holder (5) of the at least two tool holders (5) is designed such that it can switch into a standby mode while remaining at the bridge (3) if the particular packaging process to be performed by the packaging robot (15, 16, 17) does not require the at least one tool holder (5) to be equipped with a tool head (7).

2. The packaging robot of claim 1, wherein the at least one tool holder (5) is arranged in a waiting position at the bridge (3) when in standby mode.

3. The packaging robot of claim 2, further comprising at least one pneumatic cylinder, wherein the at least one pneumatic cylinder can transfer the at least one tool holder (5) into the waiting position.

4. The packaging robot of claim 2, further comprising at least one servo drive, wherein the at least one servo drive can transfer the at least one tool holder (5) into the waiting position.

5. The packaging robot of claim 2, wherein each of the at least two tool holders (5) is associated with an own drive (4), such that the own drive (4) can bring each of the at least two tool holders into a waiting position.

6. The packaging robot of claim 5, wherein each own drive (4) comprises a pneumatic cylinder or a servo drive.

7. The packaging robot of claim 2, wherein the at least one tool holder (5) is movable along the bridge (3) when in standby mode.

8. The packaging robot of claim 2, wherein each of the at least two tool holders (5) each has an electric or pneumatic power supply to a tool head (7), wherein the power supply is shut off or deactivated when in standby mode.

9. The packaging robot of claim 2, wherein each of the at least two tool holders (5) comprises a quick-change mechanism (6), via which quick-change mechanism (6), a tool head (7) can be arranged without tools to the at least one tool holder (5), or via which quick-change mechanism (6), a tool head (7) can be removed without tools.

10. The packaging robot of claim 2, wherein the bridge (3) is part of a gantry system, and which gantry system can move the bridge (3) together with the tool heads (7) back and forth along a specified work path within a work cycle.

11. A method (100) used to perform a packaging process for articles comprising: providing a packaging robot (15, 16, 17) with a bridge (3) and at least two tool holders (5) arranged at the bridge (3), wherein the at least two tool holders (5) are each movable along the bridge (3) and can each accommodate a tool head (7); selecting a specific packaging process out of a plurality of different packaging processes, and equipping the at least two tool holders (5) with a particular tool head (7), performing of the selected packaging process by the packaging robot (15, 16, 17) by at least moving the equipped tool holders (5) together with the tool heads (7) along the bridge (3), wherein at least one tool holder (5) of the at least two tool holders (5) switches into a standby mode wherein the at least one tool holder (5) remains while the selected packaging process is being performed if the selected packaging process does not require the at least one tool holder (5) to be equipped with a tool head (7).

12. The method of claim 11, wherein the at least one tool holder (5) of the at least two tool holders (5) is in a waiting position when in standby mode while the selected packaging process is being performed.

13. The method of claim 12, wherein the at least one tool holder (5) is transferred into the waiting position by a pneumatic cylinder.

14. The method of claim 12, wherein the at least one tool holder (5) is transferred into the waiting position by a servo drive.

15. The method of claim 11, wherein the at least one tool holder (5) of the at least two tool holders (5), when in standby mode, is moved with the remaining tool holders (5) while the selected packaging process is being performed.

16. The method of claim 11, wherein the tool holders (5) each supply their particular tool head (7) with electric or pneumatic power while the selected packaging process is being performed, and wherein the electric or pneumatic power is switched off during the standby mode.

17. The packaging robot of claim 2, wherein the at least one tool holder (5) is immovable when in standby mode.

18. The packaging robot of claim 12, wherein the at least one tool holder (5) is immovable when in standby mode.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0056] In the following passages, the attached figures further illustrate typical embodiments of the invention and their advantages. The size ratios of the individual elements in the figures do not necessarily reflect the real size ratios. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged in relation to other elements in order to facilitate an understanding of the invention.

[0057] FIGS. 1 and 2 show an embodiment of a bridge such as can be provided in various embodiments of a packaging robot according to the invention.

[0058] FIGS. 3 and 4 each show schematic views of an article packaging facility in which embodiments of a packaging robot according to the invention are used.

[0059] FIGS. 5 and 6 each show schematic views of another article packaging facility in which embodiments of a packaging robot according to the invention are used.

[0060] FIG. 7 shows a flowchart of individual steps such as can be provided in an embodiment of a method according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0061] The same or equivalent elements of the invention are designated using identical reference characters. Furthermore and for the sake of clarity, only the reference characters relevant for describing the individual figures are provided. It should be understood that the detailed description and specific examples, while indicating preferred embodiments, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

[0062] The embodiments, examples and alternatives of the preceding paragraphs, the claims, or the following figures and description, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible.

[0063] If illustrations and aspects are generally referred to as being “schematic” in the context of the figures, this is by no means intended to imply that the illustrations of the figures and their description are of inferior significance with regard to the disclosure of the invention. The person skilled in the art is fully capable of gathering sufficient information from the schematically and abstractly drawn illustrations for facilitating the understanding of the invention without the understanding being in any way impaired by, for example, the size ratios being drawn and being potentially not precisely true to scale. On the basis of the more concretely explained realizations of the method according to the invention and on the basis of the more concretely explained functionality of the packaging robot according to the invention in the figures, the person skilled in the art as a reader is thus enabled to derive a better understanding of the inventive idea, which is formulated in a more general and/or more abstract manner in the claims and in the general part of the description.

[0064] FIGS. 1 and 2 show an embodiment of a bridge 3 such as can be provided in various embodiments of a packaging robot 15, 16, 17 (cf. FIGS. 3 to 6) according to the invention. In the present instance, four tool holders 5 are arranged at the bridge 3, each of the tool holders being configured as quick-change mechanism and each carrying a tool head 7.

[0065] The tool heads 7 are merely schematically indicated, and they can each have a plurality of suction instruments that are controllable via negative pressure and that receive beverage containers to be transferred into a particular outer packaging. The tool heads 7 can also each comprise a working tool that can seize and expand a particular folded outer packaging 9 (cf. FIGS. 3 to 6).

[0066] The configuration illustrated in FIG. 1 of the bridge 3 with four tool holders 5 and four thereto arranged tool heads 7 is provided to perform a packaging process as is shown in the schematic view according to FIG. 3.

[0067] FIG. 3 shows a layout of a facility 50, which can package articles in the form of beverage containers. For this purpose, the article packaging facility 50 comprises three packaging robots illustrated with the reference numbers 15, 16, and 17. Each of these packaging robots 15, 16, and 17 comprises a bridge 3 with exactly four tool holders 5 arranged thereto, the tool holders 5 each carrying a tool head 7 according to FIG. 1.

[0068] The packaging robots 15, 16, and 17 are moreover each designed as a gantry system and can thus move the bridge 3 together with the tool holders 5 and the tool heads 7 arranged to the tool holders 5 as a gantry system.

[0069] The bridge 3 is thus guided as a component of a gantry system, and for packaging articles, it can be moved together with the tool holders 5 arranged at the bridge 3 and the tool heads 7 arranged to the tool holders 5.

[0070] With regard to the schematic view according to FIG. 1, the tool holders 5 can be moved, together with the tool heads 7, back and forth, perpendicular to the image plane by the packaging robot 15, 16, and 17 designed as a gantry system accordingly moving the bridge 3. This direction along which the gantry system moves the bridge 3 back and forth is indicated in FIG. 3 by an arrow-based illustration in movement direction BR.

[0071] In the article packaging facility 50 as illustrated in FIG. 3, the packaging robot 15 comprises four tool heads 7, which are each arranged to a tool holder 5 and which are being carried by a bridge 3 according to FIG. 1. The tool heads 7 of the packaging robot 15 each comprise a plurality of pneumatic, controllable suction instruments, which can each temporarily receive beverage containers via negative pressure in order for the beverage containers to be placed into the outer packagings illustrated with the reference number 9.

[0072] In this context, each of the four tool heads 7 can receive a number of beverage containers corresponding exactly to a number of beverage containers to be placed into an assigned outer packaging 9. The packaging robot 15 thus operates in a cycled manner and in each cycle receives a number of beverage containers intended to be placed into four assigned outer packagings 9, transports these beverage containers toward the four outer packagings 9, and then places these beverage containers in a direction coming from above into the four outer packagings 9.

[0073] If the article packaging facility 50 is used, for example, to produce packs 8 comprising exactly six beverage containers, the tool heads 7 of the packaging robot 15 each receive exactly six beverage containers. These beverage containers are supplied via an infeed 10 guiding the beverage containers in a plurality of parallel rows along the conveying direction FR, which infeed 10 can comprise a plurality of lane guides to form the plurality of parallel rows.

[0074] Like the packaging robot 15, the packaging robot 16 also comprises a bridge 3 with exactly four tool holders 5 arranged thereat, the tool holders 5 each being configured as a quick-change mechanism 6. According to the illustration of FIG. 1, exactly four tool heads 7 are arranged likewise to the tool holders 5 of the packaging robot 16.

[0075] The tool holders 5 of the packaging robot 16 can also be moved, together with the thereto arranged tool heads 7, back and forth in the direction BR indicated with arrow-based illustration in FIG. 3 by the bridge 3 being accordingly moved via the gantry system. In contrast to the packaging robot illustrated in FIG. 3 with reference number 15, the tool heads 7 in the packaging robot 16 are equipped with work tools via which the tool heads 7 of the packaging robot 16 can take folded outer packagings 9 from the magazine 20, can expand the folded outer packagings 9, and can then deposit the outer packagings 9 on the horizontal conveyor 30.

[0076] For this purpose, the packaging robot 16 moves its bridge 3 back and forth between the magazine 20 and the horizontal conveyor 30. The packaging robot 16 also operates in a cycled manner and can take exactly four outer packagings 9 from the magazine 20 in one step, can then expand these four outer packagings 9 taken from the magazine 20, can move four outer packagings 9 toward the horizontal conveyor 30, and can deposit four outer packagings 9 at least approximately simultaneously on the horizontal conveyor 30.

[0077] In this context, the configuration of the packaging robot 15 is adapted to the configuration of the packaging robot 16. As already mentioned, the packaging robot 16 can take exactly four outer packagings 9 simultaneously from the magazine 20, can expand them, and can then deposit the four outer packagings 9 on the horizontal conveyor 30. The packaging robot 15 can receive exactly four article assemblies simultaneously from the infeed 10, which article assemblies are to be placed into these four outer packagings 9, can move the four article assemblies to the horizontal conveyor 30, and can then place the four article assemblies into the exactly four outer packagings already having been deposited by the packaging robot 16 on the horizontal conveyor 30 for this purpose.

[0078] The outer packagings 9 are moved together with the articles placed therein into the working range of the packaging robot 17 by the horizontal conveyor 30. The packaging robot 17 is also designed as a gantry system and has a bridge 3, which the packaging robot 17 designed as gantry system can move back and forth in the movement direction BR between the horizontal conveyor 30 and the further horizontal conveyor 32.

[0079] Again, exactly four tool holders 5 with exactly four tool heads 7 located thereto are arranged at the bridge 3 of the packaging robot 17 designed as a gantry system. Again, the packaging robot 17 can thus receive four outer packagings 9 with articles placed therein or four packs 8 simultaneously from the horizontal conveyor 30, move them toward the further horizontal conveyor 32, and deposit them on the further horizontal conveyor 32 by using a cycle.

[0080] After having deposited these four outer packagings 9 with the articles or beverage containers placed therein on the further horizontal conveyor 32, the packaging robot 17 can move the bridge 3 back toward the horizontal conveyor 30 and can again receive four further outer packagings 9 with articles placed therein within a further cycle. The configuration of the packaging robot 17 is thus also in each instance adapted to the configuration of the packaging robot 15 and to the configuration of the packaging robot 16.

[0081] It is thus discernible from the described operating mode of the article packaging facility 50 as designed in FIG. 3 that the packaging robots 15, 16, and 17 each have to be configured such that a specified packaging process corresponding to a specific format can be performed together by the packaging robots 15, 16, and 17. If the packaging process or the format is changed, it may be possible that the article packaging facility 50 according to a configuration of FIG. 3 is not able to perform this packaging process or yields a reduced throughput.

[0082] In practice, a change of the packaging process therefore frequently makes it necessary that each of the bridges 3 of the packaging robots 15, 16, and 17 is exchanged, which requires inconvenient conversions and leads to a disruption of a packaging process to be performed via an article packaging facility 50 until the conversion has been completed.

[0083] It is discernible from FIG. 4 that the article packaging facility 50 of FIG. 3 has undergone a change of configuration or a format change. Articles or beverage containers continue to be supplied via the infeed 10 in a plurality of parallel rows and to be transported into a working range of the packaging robot 15. The packaging robot 15 in the configuration of an article packaging facility 50 according to FIG. 4 continues to receive beverage containers from the infeed 10, to transport these beverage containers toward the horizontal conveyor 30, and to then place the beverage containers into assigned outer packagings 9.

[0084] As already explained above with regard to the article packaging facility 50 according to FIG. 3, a plurality of beverage containers are received from the infeed 10 simultaneously in the appropriate number of beverage containers to be placed into exactly four outer packagings 9 within a work cycle. In the configuration of an article packaging facility 50 according to FIG. 4 it is by contrast provided that the packaging robot 15 receives beverage containers from the infeed 10 in the appropriate number of beverage containers that are placed into exactly three assigned outer packagings 9 within a work cycle.

[0085] For this purpose, the packaging robot 15 in the configuration of an article packaging facility 50 according to FIG. 4 comprises a bridge 3 as is illustrated in FIG. 2. FIG. 2 shows that a tool head 7 is arranged to each of the three tool holders 5, which are each configured as a quick-change mechanism 6. Via each of these tool heads 7 it is possible to receive in each instance a number of articles or beverage containers to be placed into a particularly assigned outer packaging 9 within a work cycle.

[0086] A fourth tool head, as is required for each of the packaging robots 15, 16, and 17 in the configuration of an article packaging facility 50 according to FIG. 3, can be omitted in the configuration of an article packaging facility 50 according to FIG. 4.

[0087] The configuration of an article packaging facility 50 according to FIG. 4 does not require a fourth tool head 7 in order to receive articles or beverage containers from the infeed 10 and to place them in a corresponding outer packaging 9, so the tool holder 5 without a tool head 7 that is illustrated on the left side in FIG. 2 is in standby mode, in which this tool holder 5 remains at the bridge 3. An active mode of the tool holder 5, in which the tool holder 5 receives articles via a tool head 7 and places them into an outer packaging 9 during a packaging process, can be switched into a standby mode of the tool holder 5, as is illustrated in FIG. 2.

[0088] The standby mode in the exemplary embodiment of a bridge 3 according to FIGS. 1 and 2 is sometimes characterized in that the tool holder 5 illustrated on the left side moves into the waiting position shown in FIG. 2 and remains in this waiting position while the packaging robot 15 receives beverage containers from the infeed 10, moves the beverage containers toward the horizontal conveyor 30, and then places them into an assigned outer packaging 9.

[0089] All tool holders 5 arranged at the bridge 3 according to FIGS. 1 and 2 have own drives 4, which can be designed as linear motors, servomotors, or as pneumatic cylinders, for example. The tool holder 5 not required for the particular packaging process to be performed can move into the waiting position according to FIG. 2 via its own drive 4, and it can remain in the particular waiting position while the particular packaging process is being performed.

[0090] It has proved successful, for example, that the packaging process to be performed by the packaging robots 15, 16, and 17 or by the article packaging facility 50 is specified to the control device and/or regulating device S by a user. The control device and/or regulating device S can then control the particular own drive 4 of a particular tool holder 5 as required such that the particular tool holder 5 moves independently into a waiting position if the particular tool holder 5 or a tool head 7 to be arranged thereto is not required in order to perform the particular packaging process.

[0091] During an operation of the particular packaging robot 15, 16, and 17, the particular tool heads 7 arranged to a particular tool holder 5 are supplied with power or with electric or pneumatic power via the particular tool holder 5. Such a supply with electric or pneumatic power for a tool head 7 can be cut off for a tool holder 5 by the control device and/or regulating device S when the particular tool holder 5 is in standby mode. This can prevent a tool head 7 from carrying out operations when the tool head 7 is not required for the particular packaging process or when it is arranged to a tool holder 5 in standby mode.

[0092] In practice, however, it is advantageous for the particular tool head 7 to be removed from the particular tool holder 5 when it is not required for the particular packaging process. FIG. 2 also shows that the tool holder 5 in standby mode is situated in an edge area of the bridge 3 such that a tool head 7 possibly still arranged to the tool holder 5 can be easily removed from the tool holder 5.

[0093] With the tool holders 5 each being configured as quick-change mechanism 6, a removal of a particular tool head 7 from a particular tool holder 5 can moreover be carried out in a time-optimized manner.

[0094] It is moreover discernible from FIG. 4 that the packaging robot 16 takes three outer packagings 9 from the magazine 25 and deposits them on the horizontal conveyor 30 in each cycle. Furthermore, it is discernible from FIG. 4 that the packaging robot 17 in each instance receives three packs 8 from the horizontal conveyor 30 and transfers them to the horizontal conveyor 32 or deposits the three packs 8 on the horizontal conveyor 32 within a particular cycle.

[0095] The packaging robots 16 and 17 also require exactly three tool heads 7 in order to perform their particular work cycle, with a fourth tool head 7 as illustrated in FIG. 1 not being required for the configuration of an article packaging facility 50 according to FIG. 4. Exactly one tool holder 5 in each of the packaging robots 16 and 17 is therefore also in standby mode and in this context arranged to be immovable in a waiting position as shown in FIG. 2. The particular tool holder 5 is brought into the particular waiting position via an own drive 4, which can be designed as linear motor, servomotor, or as pneumatic cylinder, for example. The configurations of the packaging robots 15, 16, and 17 are thus also adapted to each other in the article packaging facility 50 according to FIG. 4.

[0096] FIG. 5 shows a schematic view of another embodiment of an article packaging facility 50. The configuration of the article packaging facility 50 according to FIG. 5 corresponds to the configuration of the article packaging facility 50 according to FIG. 4. For each of the bridges 3 of the packaging robots 15, 16, and 17, a particular tool holder 5 is therefore in standby mode and arranged in a particular waiting position. An electric or hydraulic power supply for a tool head 7 is in each instance deactivated for the particular tool holder in standby mode.

[0097] It is discernible from FIGS. 4 and 5 seen in conjunction that the embodiment of the article packaging facility 50 according to FIG. 5 has a first magazine 20 and a second magazine 25. The first magazine 20 accommodates folded outer packagings 9 prepared for a packaging process in which the packaging robot 16 takes four outer packagings 9 simultaneously from the magazine 20, expands the outer packagings 9, and deposits them on the horizontal conveyor 30. The second magazine 25 accommodates folded outer packagings 9 prepared for a packaging process in which the packaging robot 16 takes exactly three outer packagings 9 simultaneously from the magazine 25, expands the outer packagings 9, and deposits them on the horizontal conveyor 30.

[0098] Depending on the particular packaging process to be performed, the packaging robot 16 can optionally take folded outer packagings 9 from the first magazine 20 or from the second magazine 25. Both the first magazine 20 and the second magazine 25 are situated within a working range of the packaging robot 16 such that their position does not need to be changed if the particular packaging processes are changed. A change between different packaging processes can be carried out in a fast and uncomplicated manner in such embodiments.

[0099] FIGS. 5 and 6 seen in conjunction illustrate such a change. The packaging robot 16 in FIG. 5 still takes exactly three outer packagings 9 from the second magazine 25, expands the outer packagings 9, and deposits them on the horizontal conveyor 30 within a particular work cycle, whereas in the configuration of the article packaging facility 50 according to FIG. 6, exactly four outer packagings 9 are taken from the first magazine 20, are expanded, and are then deposited on the horizontal conveyor 30 by the packaging robot 16 within a particular cycle.

[0100] Both in the configuration of the article packaging facility 50 according to FIG. 5 and in the configuration of the article packaging facility 50 according to FIG. 6, the first magazine 20 and the second magazine 25 are each designed as components of the article packaging facility 50, and they remain installed as fixed components of the article packaging facility 50 without being removed from the article packaging facility 50 in the instance of a packaging process being changed.

[0101] FIG. 7 shows a flowchart of individual steps such as can be provided in an embodiment of a method 100 according to the invention. To perform the method as illustrated in the individual steps of FIG. 7, a packaging robot 15, 16, or 17 is provided with a bridge 3 and with a plurality of tool holders 5 arranged at the bridge 3, with the plurality of tool holders 5 arranged at the bridge 3 each being movable along the bridge 3 and each being able to accommodate a tool head 7.

[0102] In the context of a first step indicated with reference number 110, a specific packaging process is selected from a plurality of different packaging processes, which selectively equip a particular tool head 7 to the at least two tool holders 5 arranged at the bridge 3. The selection of the specific packaging process is carried out via a control device and/or regulating device S, for which a user specifies information on the particular packaging process to be performed.

[0103] In the context of a further step 120, the control device and/or regulating device S checks which of the tool holders 5 require to be equipped with a particular tool head 7 in order for the particular selected packaging process to be performed. If the control device and/or regulating device S determines that the performing of the selected packaging process requires no equipping of one or more of the tool holders 5 with a tool head 7, the control device and/or regulating device S causes the one or more tool holders 5 to switch into standby mode in step 120. For this purpose, these tool holders 5 or this one tool holder 5 are/is moved into a particular waiting position and in this context continue/continues to be arranged at the bridge 3.

[0104] Step 120 is followed by method step 130. In step 130, the packaging process is performed by the packaging robot 15, 16, or 17. In this context, the packaging robot 15, 16, or 17 moves the tool holders 5 equipped with tool heads 7 along the bridge 3 and hereby performs a packaging step necessary to produce an article pack 8. It is possible in this context that the packaging robot 15, 16, or 17 moves articles toward an outer packaging 9 and places the articles into the particular outer packaging 9.

[0105] It is also possible that the packaging robot 15, 16, or 17 in this context takes outer packagings 9 from a magazine 20 or 25 expands the outer packagings 9, and then deposits them on a horizontal conveyor 30. While the packaging process is being performed, the tool holders 5 that do not require to be equipped with a tool head 7 for the performing of the selected packaging process continue in the standby mode, which the tool heads 7 have already switched to prior to the start of the packaging process.

[0106] The invention has been described with reference to a preferred embodiment. Those skilled in the art will appreciate that numerous changes and modifications can be made to the preferred embodiments of the invention and that such changes and modifications can be made without departing from the spirit of the invention. It is therefore intended that the appended claims cover all such equivalent variations as fall within the true spirit and scope of the invention.

LIST OF REFERENCE NUMBERS

[0107] 3 Bridge

[0108] 4 Own drive

[0109] 5 Tool holder

[0110] 6 Quick-change mechanism

[0111] 7 Tool head

[0112] 8 Pack

[0113] 9 Outer packaging

[0114] 10 Infeed

[0115] 15 Packaging robot

[0116] 16 Packaging robot

[0117] 17 Packaging robot

[0118] 20 Magazine, first magazine

[0119] 25 Magazine, second magazine

[0120] 30 Horizontal conveyor

[0121] 32 Further horizontal conveyor

[0122] 50 Article packaging facility

[0123] 100 Method

[0124] 110 First method step

[0125] 120 Second method step

[0126] 130 Third method step

[0127] BR Movement direction

[0128] FR Conveying direction

[0129] S Control device and/or regulating device