EP3195934B1 - Grinding device and method for operating the same - Google Patents

Description

AREA OF APPLICATION AND PRIOR ART

The invention relates to a crushing device for crushed material such as memory cards, mobile terminals or the like., So in particular relatively stable, rigid and sometimes thick or voluminous and possibly smooth crushed material. Furthermore, the invention relates to a method for operating such a comminution device.

Various similar shredding devices, also called shredders, are known from the prior art. These can be designed not only for shredding paper, but also for CDs, such as the DE 19912036 A1 , or various other media such as according to the DE 10008442 A1 , However, these shredders are not suitable for mobile terminals such as mobile phones or tablet computers.

From the WO 95/13139 A1 For example, a waste shredder, such as containers or bottles, is known having a cutter with two cooperating and oppositely driven cutting drums. These consist of alternately arranged cutting discs with teeth, wherein the cutting discs of the two cutting rollers alternately engage each other. There is a feed path for items to be shredded, which ends above the cutting unit. It has a ramp to direct objects to be crushed in the direction of the cutting discs.

From the US 4,669,673 A Another shredding device is known in particular to crush bottles or similar containers. It has a cutter with two cutting rollers, each having intermeshing cutting discs with cutting teeth. Above the cutting mechanism, two supply means rotate in opposite directions, each having paddle-like protruding surfaces which run parallel to the longitudinal direction of the rotary shafts and rotate in opposite directions.

From the WO 03/033153 A1 For example, another document shredder is known having a cutter with two cutting rollers having alternating intermeshing discs. On the cutting discs teeth are arranged, which are each twisted slightly in the longitudinal direction of the cutting rollers together with cutting disc to the previous cutting disc. This twist is for the two side by side and interlocking Cutting rollers in the same direction. This allows documents to be better shredded or cut into smaller particles.

TASK AND SOLUTION

The invention has for its object to provide an aforementioned crushing device and an aforementioned method for their operation, with which problems of the prior art can be avoided and it is particularly possible, the aforementioned crushed material, especially mobile devices, simple, good and secure to crush. In particular, it is important that stored on this shredded digital data can no longer be read or used.

This object is achieved by a comminution device with the features of claim 1 and by methods having the features of claim 12. Advantageous and preferred embodiments of the invention are specified in the further claims and are explained in more detail below. Some of the features are described only for the comminution device or only for the method of their operation. However, they should be able to apply independently and independently of each other both for the comminution device and for the method. The wording of the claims is incorporated herein by express reference.

It is envisaged that the comminution device has a comminution unit, which in itself has, in a substantially known manner, two cooperating cutting rollers which are rotatably driven in mutually opposite directions of rotation. The cutting rollers each have alternately arranged and intersecting or intermeshing cutting discs, which together form a so-called cutting gap over the length of the cutting rollers. This cutting gap is the area in which comminuted material comes into contact with both cutting rollers and thus its comminution is started. In this case, cutting discs of a cutting roller each engage in an annular groove between adjacent cutting discs of the other cutting roller. Advantageously, this intervention is alternating. With particular advantage all but the outermost cutting disks at each of the two ends of the cutting rollers abut all cutting disks on two adjacent cutting disks of the opposite cutting drum. In this case, then no broad open spaces or the like. intended.

The cutting discs have, in a manner known per se, cutting edges on their outer edge edges which cooperate with corresponding cutting edges of the cutting discs of the other cutting roller. Furthermore, the cutting disks have a plurality of teeth along the outer circumference, for example 6 teeth to 20 teeth. Each tooth has a tooth tip and a tooth cutting edge on this tooth tip. Advantageously, the teeth are identical in their shape for all cutting wheels equal or particularly advantageous even identical.

According to the invention, it is provided that the teeth or the tooth cutting edges of the cutting disks are aligned in such a way that they lie next to the teeth or tooth cutting edges of the other cutting roller during rotation of the cutting rollers in one working direction during operation of the comminution unit or the comminuting apparatus. This means that the cutting discs of the two cutting rollers, so to speak, hit tooth on tooth and not, as provided in part in the aforementioned prior art, make the teeth of the cutting discs of a cutting roller in recesses between two teeth in the other cutting roller. This advantageous meeting of opposing teeth, the aforementioned stable and sometimes even crushed material such as mobile devices in particular are well gripped and pulled for shredding between the cutting rollers.

Furthermore, a feed with a feed path for the comminuted material is provided to the crushing plant. This can be, for example, a kind of track or slide to bring the crushed material automatically to the crushing plant. In this case, this feed or the feed path should be above the crushing plant or run, in particular with a slope, so that the crushed material automatically after laying or Feeding into the crusher slips to shredding. The feed path can end above the comminution unit or above the cutting gap, a distance can advantageously be about 5 cm to 20 cm. Below the end of the feed path and above the crushing unit or above the cutting gap, an elongated guide device is arranged, which is advantageous in the manner of a long projection or in the manner of a guide rib or the like. can be trained. In this case, the guide device extends over a length of at least 30% of the length of the cutting rollers or of the cutting gap. Furthermore, the guide device is inclined in its longitudinal course by a fastening to the crushing device or in a guide shaft towards the free end downwards. An inclination angle can be 1 ° to 20 ° or even up to 45 °. Due to the inclination, the comminution material reaching the guide device can automatically slide along it and, in particular in the case of particularly large comminuted material, be guided by a special design of the guide device into a specific region of the cutting rollers or the comminution unit. In a further embodiment of the invention, this region can then be particularly well suited for the comminution of such large comminuted material and be designed accordingly.

Thus, a crushing device is provided by the invention, which is particularly suitable for stable, smooth and possibly also thick crushed material. For such comminuted material, especially the inventive design of the cutting discs or the teeth and their arrangement has been found to be advantageous on the cutting discs and cutting rollers.

By the guide device according to the invention, it is possible that different sized crushed material is processed differently in the crushing work or is processed by the supply to different areas of the cutting rollers respectively appropriate. This can be on separate feed openings or the like. as according to the DE 10008442 A1 be waived.

In an advantageous embodiment of the invention, a tooth cutting of the teeth or the cutting discs may have a longitudinal direction parallel to the longitudinal directions of the cutting rollers. This means that the tooth cutting edge is transverse to the plane of the cutting discs. Preferably, the cutting rollers are parallel to each other.

In an advantageous embodiment of the invention, the teeth of directly interlocking adjacent cutting discs to a median plane between the cutting rollers, which are also perpendicular to a plane in which the axes of rotation of the cutting rollers are mirror-symmetrical, particularly advantageous in each position of the cutting discs or teeth. This means that in each rotational position of the cutting rollers, the teeth of directly intermeshing opposed cutting discs have the same distance from each other and, so to speak, simultaneously hit this center plane. Thus, the aforementioned stable or stiff and smooth objects of the crushed material can be better grasped and pulled into the crushing plant.

The distances of the teeth on a cutting disc are advantageously uniform. This applies in particular to all cutting discs of a cutting roller or all cutting discs of both cutting rollers. Thus, a production of the crushing device or the cutting rollers can be simplified.

In an advantageous embodiment of the invention, the teeth of the cutting discs are designed so that they are sawtooth-shaped forward and inclined in the direction of rotation of the cutting rollers. Such relatively sharp teeth can very well grab the said comminution material in order to pull it into the comminution unit or cutting unit.

In an embodiment of the invention can be provided that in the cutting rollers or in the cutting discs recesses are provided along the cutting rollers which form the aforementioned teeth or through which the teeth are worked out. These recesses and the teeth of a cutting roller may each extend along lines which are non-parallel to the longitudinal axis of the cutting roller or which have an angle between 1 ° and 10 °, preferably at most 5 °, to a plane through the longitudinal axis of the cutting roller or include. In simple words, the lines run around the cutting rollers as slightly helical spirals. Through this course of the depressions and teeth, it is possible that in a region of the cutting rollers or of the comminuting unit, in which the depressions in the two cutting rollers have a larger distance from one another, larger free spaces are created between the cutting disks or tooth cutters in the cutting gap, in which large items to be crushed as crushed can be used particularly well to be crushed.

For the guide device according to the invention can also be provided that it covers between 30% and 70% of the length of the cutting gap between the cutting rollers, advantageous between 40% and 60%. It should therefore not run over the entire cutting gap, since in the free area especially large crushed material is to be introduced into the crushing unit or between the cutting rollers. The guide device, in particular also with its inclination according to the invention or its oblique course for automatically slipping the comminuted material, is used for this purpose. The guide device can advantageously extend directly above the cutting gap or above the cutting rollers. It can be particularly advantageous while covering a center line between the two cutting rollers at least partially.

While the guide advantageously in its longitudinal course towards a free end, which ends so to speak over the crushing unit or on the cutting gap is inclined, it can be inclined in flat configuration in a direction transverse to it, ie in the width direction, towards a wall of a guide shaft be attached to it or at least to which it is very close. It can thus be achieved that the comminuted material also actually slides along the guide device as far as its free end and does not slip sideways into the comminuting device. Advantageously, such a guide device is designed as a sheet metal, particularly advantageously without openings, so that no crushed material can catch or get caught therein.

In an embodiment of the invention, a guide shaft may be provided between the feed path from above and the comminution unit below or the cutting rollers. The feed path can reach to one side of the guide shaft, wherein it advantageously extends transversely to the longitudinal direction of the cutting rollers.

For such a guide shaft can be provided that the guide device according to the invention is arranged on the feed path opposite side of the guide shaft, but in any case under the feed path. Thus, large objects to be shredded can slide over the feed track, first falling onto the guide device, then again sliding along this until reaching a desired area above the cutting rollers. Then they can fall from the guide down into the crushing plant or on the cutting rollers.

A width of the guide device may be between 30% and 70%, advantageously between 40% and 60%, of the width of the guide shaft in this direction. So just large items to be shredded can be easily absorbed to slide along on the Guide device, while small crushed material may also fall laterally past the guide directly into the cutting gap or between the cutting rollers.

The guide shaft may have a length corresponding to the cutting gap and a width in the range of 10% to 30% of the length. In absolute terms, this can be a length of about 15 cm to 50 cm and a width of 2 cm to 15 cm. A diameter of the cutting discs may be about 4 cm to 8 cm or even 10 cm. Their thickness can vary between 1 mm and 10 mm.

In a method according to the invention for operating a previously described comminution device, a load measurement during operation is carried out on a drive motor for the comminution plant, which advantageously drives both cutting rollers, when comminution material has been introduced. This is achieved particularly advantageously by detecting the current that the drive motor requires. Thus, it can be detected depending on the load condition of the drive motor, whether the crushing plant has grinded shredded material. Such methods are known in the art from the prior art and need not be explained in detail here. It is recognized that the crushing plant has gripped a shredded material, for example after it has been automated by a light barrier or the like. has been put into operation, so it performs a conventional crushing operation. However, if it is detected via the load measurement that the comminution plant has not gripped a feed material to be comminuted, because the load on the drive motor does not increase, then after a short time, advantageously between 1 or 2 and 20 seconds, the drive motor is reversed, so that it can Turning crusher in the opposite direction. The direction of rotation of the cutting rollers is thus reversed compared to the working direction. This again can be done for a short time, advantageously between 0.5 second and 5 to 10 seconds. As a result, the location of a crushing material or an object to be crushed, which is likely already applied to the cutting rollers or resting on them, but has not yet been gripped by the teeth to be changed so that this is possible. Then the drive motor is stopped again and the crushing unit is rotated by the drive motor again in its normal working direction. In this case, the comminuted material should then advantageously have been gripped by the teeth or by the comminution unit.

If the material to be comminuted has still not been grasped sufficiently well to be retracted, this process can be repeated once or several times, whereby the position of the comminuted material is to be changed as much as possible each time. This repetition can be done between 2 times and 10 times. If, after a load measurement, no detection and comminution of comminution material has still been recorded, then an error message or a corresponding alternative message can be output to an operator. Then it has to remove the shredded material or otherwise try to shred it.

These and other features will become apparent from the claims but also from the description and drawings, wherein the individual features each alone or more in the form of sub-combination in one embodiment of the invention and in other areas be realized and advantageous and protectable Represent embodiments for which protection is claimed here. The subdivision of the application into individual sections as well as intermediate headings does not restrict the general validity of the statements made thereunder.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1

eine seitliche Schnittdarstellung einer erfindungsgemäßen Zerkleinerungsvorrichtung,

Fig. 2

eine Vergrößerung eines Zerkleinerungswerks der Zerkleinerungsvorrichtung aus Fig. 1,

Fig. 3

eine vereinfachte Darstellung des Zerkleinerungswerks aus Fig. 2 mit den Schneidwalzen und Schneidscheiben samt einer gestrichelt dargestellten Mittelebene und

Fig. 4

eine Schnittdarstellung der Zerkleinerungsvorrichtung aus Fig. 1 von oben mit Blick in das Zerkleinerungswerk.

Embodiments of the invention are shown schematically in the drawings and are explained in more detail below. In the drawings show:

Fig. 1

a side sectional view of a crushing device according to the invention,

Fig. 2

an enlargement of a crushing plant of the crushing device Fig. 1 .

Fig. 3

a simplified representation of the crushing plant Fig. 2 with the cutting rollers and cutting discs together with a dashed center plane and

Fig. 4

a sectional view of the crushing device Fig. 1 from above with a view into the shredder.

DETAILED DESCRIPTION OF THE EMBODIMENT

In the Fig. 1 a shredding device 11 according to the invention is shown, as it can be used for example in an office or in a smaller company to crush the above-mentioned crushed material or to destroy especially the stored digital data. The crushing device can be about 0.8 m to 1.5 m in size and advantageously operated on a conventional power supply.

The crushing device 11 has a housing 12 with a slot-like feed opening 14 with the exemplary dimensions 4 cm x 16 cm, which is long and wide enough for the intended crushing material. Adjoining the feed opening 14 on the upper side of the comminution device 11 is a feed 16 with an oblique feed path 17. This leads to a guide shaft 19 or goes directly into one of its walls 20a and 20b, namely in the left wall 20a. The guide shaft 19 runs vertically here, but this need not be so. It has a width of 16 cm as the feed opening 14, which dimensions could well be twice as large.

Below the guide shaft 19, a guide 21 is disposed below the feed path 17, which from the top view of Fig. 4 is better to recognize. The guide 21, is looked at the bottom here, here is an elongated plate and attached to the right wall 20b of the guide shaft 19 and abuts it. It is inclined obliquely to the wall 20b right down or forms with this a kind of V-shaped groove. In its longitudinal course, it is inclined downwards in the drawing plane, which can be seen at the lower-lying free end 22. Below the guide device 21 is a crushing plant 24, which in principle has many constructive similarities with known crushing plants or cutters of shredders mentioned above. The crushing unit 24 has a drive motor 26 which, like the Fig. 4 shows left over a simplified chain shown the comminutor 24 drives in a known manner.

The crusher 24 has a left cutting roll 28a and a right cutting roll 28b with left cutting disks 29a and right cutting disks 29b, respectively. The cutting discs 29a and 29b each have teeth 30a and 30b and provided on tooth tips tooth cutters 31a and 31b. Between two successive teeth of the same cutting disc are each recesses 33 a and 33 b, as shown in the enlarged view of Fig. 2 is clearly visible. The teeth 30a and 30b are inclined in the direction of rotation or working direction of the cutting discs 29a and 29b, so that they are formed like a sawtooth or fang like. Each cutting disc 29a and 29b are each provided with 14 teeth 30a and 30b. Especially the top view of the Fig. 4 makes clear, engage the cutting discs 29a and 29b of the cutting rollers 28a and 28b directly adjacent one another. Between the annular grooves between each two cutting discs 29 of a cutting roller 28 so-called scrapers 35 are provided as fixed narrow projections, namely left scraper 35 a and right scraper 35 b. These are however from the State of the art known and are to remove particles or parts of the crushed material from the annular grooves between the cutting discs 29.

In the Fig. 4 It can also be seen how the teeth 30 and the recesses 33 run along lines which diverge slightly from left to right, here with an opening angle between the lines of both cutting rollers 28 of approximately 10 °. Thus, the slightly different opening widths are given in the right area than in the left area, each at the same time.

Down the crusher 24 is open. In a space provided below catchment 39 can or the like. are introduced to collect the crushed crushed material and collect.

In Fig.2 in the enlarged view of the crushing unit 24 together with feed 16, a cutting gap 37 is shown, which is recognizable between the two cutting rollers 28a and 28b. Here are just two teeth 30a and 30b equal to each other, so that the cutting gap 37 is almost closed. It can also be seen from the enlargement that the cutting discs 29a and 29b completely cover each other, even if the recesses 33a and 33b lie precisely on a plane in which the two axes of rotation of the cutting rollers 28a and 28b lie.

In the guide shaft 19 an expected and desired path A is shown for large crushed material, for example, the aforementioned mobile terminals. This path A comes from above via the feed 16 and the feed path 17 and leads through the guide 21. By the arrangement of the guide 21 on the wall 20b, which is opposite to the feed path 17, it is ensured that such comminuted material thereof also on the guide 21 lands. The comminuted material then slips over the free end 22 of the guide device 21 into the comminution unit 24 or onto the cutting gap 37. Like from the Fig. 4 it can be seen, the length of the guide 21 is slightly more than half the length of the cutting gap 37 and the length of the cutting rollers 28a and 28b. Im here in the Fig. 4 shown right area, the opening width at the teeth 30a and 30b is slightly larger, so that here larger objects can be better grasped and pulled into the crushing unit 24. This has already been mentioned above. The purpose of the guide device 21 is therefore to ensure that large comminuted material comes as far as possible into this right area between the cutting rollers 28a and 28b and not in the left area.

In the Fig. 2 a web B is shown for crushing material, which slides down on the feed path 17 and on the left past the guide 21 in the crushing plant 24 into it. These can be, for example, memory cards or so-called SD cards, which can be gripped easily and securely by the comminution unit 24 or the cutting rollers 28a and 28b for pulling in and crushing or destroying.

According to the track B, larger mobile terminals can also be supplied in the form of tablet computers, which thus also pass the guide device 21 and pass through the comminution work 24. However, they are not introduced via the feed opening 14. For them, a movable or displaceable flap 15, on the left of the feed opening 14 is provided, pushed to the side and then the way is directly from the top of the guide 21 over into the crushing unit 24 free. For such tablet computers, the crushing is not a problem, since they are quite thin and thus are safely gripped by the cutting rollers in each area.

Finally, a web B 'is also shown, in which small comminuted material possibly also falls onto the guide device 21, but then does not slide down over the free end 22, but rather sideways outwards. This too is certainly intended and acceptable.

A method described above for operating the comminution device 11 according to the figures is readily conceivable with reference to the figures and need not be repeated again in detail. In a power supply for the drive motor 26 is an aforementioned load measurement, which is advantageously connected to a not shown here control of the crushing device 11 for the drive motor 26. At the top of the feed opening 14 or in the feed 16, microswitches or the like can advantageously be detected via photocells, when comminution material has been introduced, alternatively also at the displaceable flap 15. Then the drive motor 26 can be started and the cutting rollers 28a and 28b the crushing unit 24 in the working direction, as in Fig. 2 located, offset. If, after a short time, for example the aforementioned few seconds, detected by the load measurement on the drive motor that the load has not risen or supplied crushed material has not yet been seized, the process of reversing the direction of rotation takes place for a short time. By reversing the direction of rotation, the material to be comminuted is to change its position or its contact with the cutting rollers 28a and 28b or the teeth 30, so that when the direction of rotation is reversed in the working direction, gripping takes place. Was the crushed then still not grasped, which can be recognized by an unchanged low load on the drive motor 26, the process of reversing the direction of rotation is repeated, possibly also several times as previously explained.

Claims (14)

1. Comminution device (11) for product for comminution such as memory cards, mobile terminal apparatuses or the like, wherein

   - the comminution device has a comminution unit (24) which has two interacting cutting rollers (28a, 28b) that are rotatably driven in mutually opposite rotational directions, each having mutually intersecting cutting discs (29a, 29b) that are disposed in an alternating manner and form a cutting gap (37);

   - the cutting discs (29a) of the one cutting roller (28a) each engage in an annular groove between adjacent cutting discs (29a) of the other cutting roller (28b);

   - the cutting discs (29a, 29b) have cutting edges on the external peripheral edges;

   - the cutting discs (29a, 29b) along the external circumference have a plurality of teeth (30a, 30b), each having one tooth tip and one tooth blade (31a, 31b) on the tooth tip;

   - the comminution device (11) has an infeed (16) having an infeed track (17) for the product for comminution to the comminution unit (24), so as to offer up in a self-acting manner the product for comminution above the comminution unit;

   - the infeed track (17) terminates above the comminution unit (24), or above the cutting gap (37), respectively, wherein an elongate piloting device (21) is disposed below the end of the infeed track and above the comminution unit;

   characterized in that

   - the tooth blades (31a, 31b) of the cutting discs (29a, 29b) are aligned such that during operation of the comminution unit (24) upon rotation of the cutting rollers (28a, 28b) they each lie beside the tooth blades of the other cutting roller and thereby mesh;

   - the piloting device (21) extends across a length of at least 30% of the length of the cutting rollers (28a, 28b), and herein slopes downward in the longitudinal profile thereof from a fastening on the comminution device (11) or in a guide duct (19), respectively, to the free end of the former.
2. Comminution device according to Claim 1, characterized in that the tooth blade (31a, 31b) has a longitudinal direction that is parallel with the longitudinal directions of the cutting rollers (28a, 28b).
3. Comminution device according to Claim 1 or 2, characterized in that the teeth (30a, 30b) of directly mutually engaging and mutually opposite cutting discs (29a, 29b) are mirror-symmetrical in relation to a central plane between the cutting rollers (28a, 28b), or in each rotary position of the cutting rollers are equally mutually spaced apart.
4. Comminution device according to one of the preceding Claims, characterized in that the spacings of the teeth (30a, 30b) on a cutting disc (29a, 29b) are uniform, in particular in the case of both cutting rollers (28a, 28b).
5. Comminution device according to one of the preceding Claims, characterized in that the teeth (30a, 30b) are configured in a saw-tooth manner so as to be forwardly oblique, pointing in the rotational direction of the cutting rollers (28a, 28b).
6. Comminution device according to one of the preceding Claims, characterized in that depressions (33a, 33b) for forming the teeth (30a, 30b) are provided in the cutting rollers (28a, 28b) or in the cutting discs (29a, 29b) thereof, respectively.
7. Comminution device according to Claim 6, characterized in that the depressions (33a, 33b) and the teeth (30a, 30b) of a cutting roller (28a, 28b) each run along lines that run so as to be non-parallel with the longitudinal axis of the cutting roller, or have an angle between 1° and 10° in relation to a plane through the longitudinal axis of the cutting roller.
8. Comminution device according to one of the preceding Claims, characterized in that the piloting device (21) covers between 30% and 70% of the length of the cutting gap (37) between the cutting rollers (28a, 28b).
9. Comminution device according to Claim 8, characterized in that the piloting device (21) runs directly above the cutting gap (37) and/or at least in regions covers a central line between the two cutting rollers (28a, 28b).
10. Comminution device according to one of the preceding Claims, characterized in that a guide duct (19) is provided between the infeed track (17) and the comminution unit (24) or the cutting rollers (28a, 28b), respectively, and the infeed track reaches up to a side of the guide duct, wherein the piloting device (21) is disposed on the opposite side of the guide duct.
11. Comminution device according to Claim 10, characterized in that a width of the piloting device (21) is between 30% and 70%, in particular between 40% and 60%, of the width of the guide duct (19) in this direction.
12. Method for operating a comminution device according to one of the preceding Claims, characterized in that load measurement is performed on the drive motor (26) for the comminution unit (24) during operation, so as to detect whether the comminution unit has acquired product for comminution, and in the case in which no acquisition of product for comminution has been detected, after a period between 2 seconds and 20 seconds the drive motor (26) rotates the comminution unit (24) in the opposite direction or reverses the rotational direction of the cutting rollers (28a, 28b) in relation to the operation direction, respectively, for a period between 0.5 seconds and 5 seconds, wherein the drive motor is subsequently stopped again and resumes driving of the comminution unit in the normal operation direction.
13. Method according to Claim 12, characterized in that upon reversal of the rotational direction of the cutting rollers (28a, 28b) and re-starting the cutting rollers in the operation direction, it is again detected by way of load measurement on the drive motor (26) whether the comminution unit (24) has acquired the product for comminution, wherein in the case in which the comminution unit has again failed to acquire the product for comminution, the operation of the comminution unit is again reversed.
14. Method according to Claim 13, characterized in that the procedure is repeated between two times and ten times.

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