The invention relates to a device for reducing paper according to the preamble of claim 1. The invention also relates to a method for reducing paper by means of such a device.

Such a device and method are known, for example from EP 0 622 120 B1. The known device comprises a cabinet-like frame. Disposed in the interior of said frame is a reducing unit. A conveyor is disposed on the cabinet-like frame. The conveyor is surrounded all around by a closable casing. The casing comprises a supply opening, which can be closed by a cover. Via said supply opening, paper to be reduced, and in particular valuable papers such as banknotes, can be placed on the conveyor. The paper is often placed on the conveyor in relatively large bundles. The conveyor then conveys the paper to be reduced to a discharge end of the conveyor, which is positioned above an opening in the cabinet-like frame, directly above the reducing unit. The paper subsequently falls into the reducing unit, where it is cut into small pieces and/or shredded.

Dust formation may occur when the conveyor is being loaded with paper to be reduced. Said dust formation is undesirable, since the dust may affect the health of a user loading the device with the paper to be reduced. Upon prolonged exposure, said dust may lead to health problems of the user. Also brief exposure may be hazardous, however, for example because the dust contains pathogens, such as toxic substances, viruses and/or bacteria.

It is an object of the present invention to provide an improved device for reducing paper, in particular valuable papers such as banknotes, wherein prolonged as well as brief exposure to dust is avoided.

In order to achieve that object, the invention provides a device of the kind referred to above for reducing paper, in particular valuable papers such as banknotes, which device is characterised by the characterizing part of claim 1. The device according to the invention comprises a reducing unit for reducing paper, in particular valuable papers. The reducing unit may be a machine provided with knives, for example. The device also comprises a conveying unit substantially enclosed by a closable casing, which comprises a conveyor, for example in the form of a conveyor belt. The device comprises an suction unit. The suction unit comprises a suction element for suctioning air, which is disposed at the supply opening. Loading the conveyor with the paper to be destroyed takes place via the supply opening. At the supply opening, the paper to be destroyed will come into contact with the conveyor, as a result of which dust from the paper to be destroyed may be released. By placing the suction element near and at the location of the supply opening, the dust will be extracted directly at the source. The dust can no longer reach the user, thereby preventing both brief and prolonged exposure to the dust. The object of the present invention is thus achieved.

It is noted that it is generally known to suction air from spaces, for example for the purpose of extracting dust. Such suctioning does not suffice, however, for preventing prolonged as well as brief exposure to dust that is released upon loading the device with paper to be reduced. The known air suction system forms part of an air conditioning unit, for example, and comprises a suction device mounted to the ceiling of the space. Such a suction device is designed for a relatively low air circulation, and is thus not capable of processing the relatively large amounts of released dust that are present at a large distance from the suction device. In addition to that, the extracted dust can pass the user while moving from the device to the ceiling, so that the user is exposed to the dust. These drawbacks do not exist when using the device according to the present invention.

The term "valuable papers" as used in the present application is understood to mean: all documents that are (can be) of value to a user, for example because they have a nominal value (for example in the case of banknotes), or because they are confidential (documents containing secret information), or because the user no longer wishes the documents to be used by third parties (expired driving licences and/or credit cards). The material is less relevant in that regard, that is, the material is not limited to paper, but the valuable papers may also be made of other materials.

In order to further prevent the spreading of dust outside the casing, it is preferable if the suction element opens directly into the interior of the casing.

In order to obtain a self-acting device, the suction unit is integrated in the device in one embodiment. The suction unit may form an integral part of the device and be connected thereto. This makes it possible to activate the suction unit simultaneously with the entire device in a simple manner. In this way unnecessary energy consumption by the suction unit is prevented, for example. In one embodiment, the suction element is disposed between the conveyor and the closing element, at least in an open position of the closing element. This is a very suitable location for the suction element, since the direct dust extraction at the source is the most effective at that position. The effectiveness is further enhanced if the suction element is disposed closer to the closing element than to the conveyor.

It is preferable in that case if the suction element is disposed above a bearing surface of the conveyor, with the perpendicular distance between the bearing surface of the conveyor and the suction element ranging between 15 cm and 90 cm, preferably between 30 cm and 60 cm. Distances such as these lead to an adequate suction action close to the source. Preferably, the part below the lower limits of said distances is free from any (additional) suction element. This leads to a loading height of about 15 cm and about 30 cm, respectively.

Direct suction action at the source is facilitated further if, at least at the location of the supply end, the casing has an upright side wall comprising the suction element at its longitudinal side.

In one embodiment, the reducing unit comprises a fan unit, wherein said fan unit is connected to the suction element via a suction duct. In this way the fan unit acts both for the reducing unit, for drawing in already reduced paper, and for the suction unit, for suctioning air near the supply opening. In this manner a compact device is obtained.

In a very advantageous embodiment, the device is provided with a control unit connected to the suction unit. In this way the suction unit can be controlled as desired by turning it on or off in dependence on the status of the other components of the device. All this will be explained in more detail hereinafter.

It is also advantageous if the suction device is provided with a sound absorber. In this way noise nuisance for the user is prevented. The sound absorber is preferably disposed on a duct that interconnects the suction element and the fan.

In an embodiment that further increases the safety of the device, and in particular reduces the risk of undesirable disappearance of valuable papers to be destroyed, such as banknotes, the suction element consists of a number of individual suction openings, which are each adapted to prevent the paper to be reduced, in particular valuable papers such as banknotes, from passing through the suction opening in question. The suction openings may be circular in shape, for example, having a diameter such that the banknote cannot be sucked therethrough. The skilled person will be able to use the correct dimensions in dependence on the document to be reduced. The suction openings may also be arranged in a regular manner so as to enlarge the effective suction surface.

According to one aspect of the present invention, there is provided a method for reducing paper, in particular valuable papers such as banknotes, using a device as described above, comprising the steps of:

A supplying the paper to be reduced to the conveyor;

B conveying the paper to be reduced to the reducing unit by means of the conveyor;

C reducing the paper to be reduced by means of the reducing unit; and

D suctioning air at the location of the supply opening by means of the suction unit.

By suctioning air at the location of the supply opening, brief and prolonged exposure to released dust is prevented. Further advantages have already been discussed in the foregoing.

In one embodiment, step D takes place prior to step C, and preferably prior to step B. The suctioning of air preferably takes place while paper to be reduced is being supplied to the conveyor, because that is the moment when there is the greatest chance of dust formation. Once the paper has been supplied to the conveyor, the supply opening can be closed. Preferably, the suction unit is stopped once the closable casing has been closed by the closing element, and no air is suctioned any more at the location of the supply opening. Subsequently, step B can be carried out. Said stopping can take place manually, but also automatically, by means of the control unit. Said control unit may for example control the suction unit as a function of the position of the closing element: if said closing element is in a closed position, the suction unit is stopped, and if the closing element is in an open position, the suction unit is activated.

In one embodiment, step D is terminated before step C, or preferably step B, is started.

In one embodiment, the method further comprises a step E, viz. extracting the reduced paper by means of a fan unit connected to the reducing unit.

In a preferred embodiment, the fan unit used in step E is also used in step D for suctioning air at the location of the supply opening. The invention will now be explained in more detail by way of illustration with reference to a few embodiments thereof, which are shown in the appended figures, in which:

Figure 1 is a side view of a device according to the present invention;

Figures 2a-b are a perspective view and a side view, respectively, of the device according to the present invention;

Figure 3 is a side view of an embodiment of a device according to the present invention;

Figures 4a-b are side views of embodiments of a suction unit;

Figures 5a-b are top plan views of embodiments of a suction unit.

Figure 1 shows a device 1 for reducing paper, in particular valuable papers such as banknotes. The device 1 comprises a reducing unit 4 for reducing the paper to be reduced. In the illustrated embodiment, the reducing unit is accommodated in the interior 3 of a cabinet-like frame 2. The device 1 also comprises a conveying unit 5 with a conveyor 7 for supplying paper to be reduced from a supply end 7a of the conveyor to the reducing unit 4 via a discharge end 7b of the conveyor. An opening 31 is to that end provided in an upper side of the cabinet-like frame 2, which opening opens into the reducing unit 4.

The reducing unit 4 may be configured in many conceivable ways that are known per se to those skilled in the art. The skilled person will be able to use the right reducing unit. In the illustrated embodiment, the reducing unit 4 comprises a pre-cutting device or pre-reducer 33, which may be configured in a manner that is known per se and by means of which paper being supplied can be pre-cut into narrow strips.

The pre-cutting device 33 is connected, via a duct 34, to a main cutting device or main reducer 35 likewise forming part of the reducing unit 4, which main cutting device may also be configured in a manner that is known per se and by means of which the material supplied from the pre-coupling device can be cut into very small parts.

The discharge side of the main cutting device is connected to a fan 36 via a duct 37. The discharge duct 47 of the fan exits the cabinet-like frame 2 at an upper side thereof. In the illustrated embodiment, the pre-cutting device 33 is disposed in such a manner that the driving mechanism 32 of the pre-cutting device, which inter alia comprises an electric motor, is positioned under the conveyor 7. The main cutting device 35 and the fan 36 are also positioned under the conveyor. In this way a very compact construction of the device can be realised. The skilled person will appreciate, however, that other configurations are also conceivable and that the invention is not limited to the position and the configuration of the reducing unit 4.

As shown in figure 1 , the conveyor 7 is substantially enclosed by a closable casing 53. Near the supply end 7a of the conveyor 7, a supply opening 12 that can be closed by means of a closing element 51 is provided for supplying paper to be destroyed to the conveyor.

The device 1 further comprises a suction unit 8 provided with a suction element 10 disposed at the location of the supply opening 12 for suctioning air. The suction element 10 opens directly into the interior 52 of the casing 53. The suction unit forms an integral part of the device 1. The suction unit is disposed in the interior 3' of a cabinet-like frame 2'. The suction element 10 is designed for suctioning air near and at the location of the supply opening 12. The suction element 10 is disposed between the closing element 51 and the conveyor 7. The suction element 10 is connected to a main duct 25 via three, in total, distribution ducts 21 , 22, 23. The discharge duct 27 of the fan 26 exits the cabinet-like frame 2' at an upper side thereof. In order to prevent noise nuisance, a sound absorber (not shown) is preferably provided between the suction element 10 and the fan 26.

As shown in figure 1 , the suction element 10 is spaced from the conveying surface of the conveyor 7 by a distance A. Said distance ensures that suctioning will take place, also if some material has already been supplied in the conveying unit 5. The suction element 10 is disposed near the upper side of the closable casing 53. The suction element 10 follows the contour of the closable casing at the location of the supply opening 12.

In the illustrated embodiment, two separate cabinet-like frames 2, 2' are provided. Said frames 2, 2' are separated by a partition. In one embodiment it is also possible, however, to provide only one cabinet-like frame, with only one internal volume.

Figures 2a and 2b are a perspective view and a side view, respectively, of a part of a device 201 for reducing valuable papers. The device 201 comprises a conveyor belt 7, which is disposed in a closable casing 253. Near a supply end 7a of the conveyor 7, the closable casing is provided with an opening 212, which can be closed by means of a closing element (not shown in figure 2a) such as a door 251 (see figure 2b). At the location of the supply end 7a, the casing 253 has side walls 212, which extend upward from the conveyor 7. Provided along a length of the opening 212 are a number of suction elements 210 of a suction unit 208. Said suction elements each comprise a number of separate suction openings 211a-c provided in the side wall 212. Each of said suction openings 211a-c is dimensioned so that paper to be reduced, in particular valuable papers such as banknotes, is prevented from passing through the suction opening 211 a-c in question. The bottom side of the suction openings 211a-c is disposed a distance A above the conveying surface of the conveyor 7, so that there is sufficient clearance for said openings at all times and said openings will be hardly obstructed, if at all, by material already loaded. Mounted on an outer side of the side wall 212 of the casing 253 is the nozzle 210a-c. Said nozzle is connected to a fan (not shown) via distribution ducts and a main duct 225, as already described with reference to figure 1 , for example. The conveyor 7 is connected to the reducing unit via a discharge end (not shown), as also already described with reference to figure 1.

Figure 3 shows an alternative embodiment of the device 101 , in which the suction duct 125 of the suction unit 108 and the suction duct 137 of the reducing unit 104 are connected to each other and to a single fan 136. Via a valve 138 controlled by a control unit 139, said fan can be used alternately for the suction unit 108 or the reducing unit 104, if desired.

The device 101 comprises a reducing unit 104 disposed in the interior 3 of a cabinet-like frame 2, which reducing unit is provided with a pre-cutting device 133, which is connected to a main cutting device 135 via a tube 134. At a discharge side thereof, a discharge duct extends to a fan 136. The reducing unit 104 further comprises a driving device 132. Said reducing unit is known per se to those skilled in the art.

Disposed on the cabinet-like frame 102 is a conveying unit 105 comprising a conveyor 107, which is enclosed by a closable casing 153 having an interior volume 152. The closable casing comprises a closing element 151 for alternately releasing and closing a supply opening 112. The conveyor comprises a supply end 107a, which is located near the supply opening 1 12, and a discharge end 107b, which is located near the supply opening 131 of the reducing unit 104.

Disposed near the supply opening 112 is another suction unit 108, which comprises a suction element 1 10 disposed between the closing element 151 and the conveyor 107 at the location of the supply opening 1 12. Said suction element 110 is disposed a distance A above the conveying surface of the conveyor 107.

In this embodiment the suction element is connected, via distribution ducts 121 , 122, 123 and a central suction duct 125, to the fan unit 136 that is also used for the reducing unit. To prevent noise nuisance, a sound absorber (not shown) is preferably provided between the suction element 1 10 and the fan 136.

A valve unit 138 is provided at the location of the fan 136 for alternately connecting the two ducts 137 and 125 to the fan 136. Said valve unit 138 is preferably connected to a control unit 139, such that the position of the valve can be (automatically) controlled in a simple manner.

The suction system is activated by means of a control valve 138. As soon as the load cover 151 is opened, the fan 136 is started and the valve 138 is put in the suction position. The fan 136 is connected to the suction duct 125 of the suction unit 108 in that situation. The dust extracted by the suction unit 108 at the location of the supply opening 112 is blown outside the device 101 ; it can be blown to a briquetting unit, for example, or to a filter plant.

Once the paper to be destroyed has been supplied to the supply opening 1 12, the load cover 151 (closing element) can be closed and the destruction process can be started. The valve 138 is now put in the destruction position. In that position, the valve 136 is connected to the suction duct 137 of the reducing unit 104. The conveyor can supply the material to be destroyed to the reducing unit 104. Via the pre-cutting device 133 and the main cutting device 135, the destroyed banknotes (shreds) are blown outside the device 127, using the same fan, whereupon the shreds can be carried to a briquetting unit, for example.

The use of one fan 136 and a valve 138 ensures in a simple manner that no suctioning will take place at the supply opening 112 during the destruction process. This is not necessary, for that matter, because the casing 153 is closed (inter alia by means of the closing element 151). Any dust in the casing 153 can be extracted via the reducing unit. Furthermore, by turning off the suction unit 108 during the destruction process, material is also prevented from being "sucked against walls" during the destruction process, which could lead to banknotes remaining behind in the system.

In the embodiment shown in figure 1 , it is also conceivable, of course, to prevent the suction unit from operating during the destruction process, which can be done by manual or automatic (controlled) switching of the two separate fans, for example.

Figures 4a and 4b show a few embodiments of the suction unit.

Figure 4a shows an embodiment of a device 301 comprising a casing 352, whose supply opening 312 can be closed by means of a closing element 351. The casing comprises a conveyor 307 having a supply end 307b located near the supply opening 312. Near the supply opening 312, an suction unit 308 is disposed in a cabinet-like frame 303, which suction unit comprises a single suction element 310 at the location of the supply opening 312.

Figure 4b shows an alternative embodiment of a device 401. The device comprises a casing 452, which has a supply opening 412 that can be closed by means of a closing element 451. A conveyor 407 having a supply end 407b is disposed in the interior of the casing 452. An suction unit 408 is disposed in a cabinet-like frame 403, near the supply opening 412. In the embodiment shown here, the suction element 410 is (integrally) connected to the closing element 451. The suction element 410 may also form part of the closing element 451.

Figures 5a and 5b show top plan views of possible embodiments of suction units 508, 608.

The embodiment of the suction unit 508 shown in figure 5a comprises a central discharge duct 525, which opens into a suction element 510 via distribution ducts 521 , 522, 523. The suction element 510 is rectangular in shape. Small openings may be provided in the side walls of the suction element parts 510a-c, as will be explained hereinafter.

The embodiment of the suction unit 608 shown in figure 5b also comprises a central discharge duct 625, which opens into two (in total) suction elements 610a, 610b via two times three distribution ducts 6 21 , 622, 623. The suction elements

610a, 610b are arranged parallel to each other and opposite each other. Small openings may be provided in the side walls of the suction elements 610a-b, as will be explained hereinafter. It will be apparent to those skilled in the art that the present invention has been described in the foregoing on the basis of a few preferred embodiments. The invention is not limited to said embodiments, however. Within the framework of the invention, equivalent variations and/or variations that may or may not be obvious to the skilled person are conceivable. Said variations may fall within the claimed scope of the invention as defined in the appended claims.