COMMINUTION DEVICE AND METHOD FOR OPERATING SUCH A COMMINUTION DEVICE

Abstract

A comminution device for product for comminution such as memory cards or mobile terminal apparatuses has a comminution unit which has two interacting cutting rollers having cutting discs that have cutting edges on the external peripheral edges and form a cutting gap. The cutting discs of the one cutting roller each engage in an annular groove between adjacent cutting discs of the other cutting roller and along the external circumference have a plurality of teeth, each having one tooth tip and one tooth blade. The tooth blades of the one cutting roller during operation upon rotation of the cutting rollers each lie beside the tooth blades of the other cutting roller. The comminution unit yet has an infeed having an infeed track for the product for comminution to the comminution unit, said infeed track terminating above the cutting gap. An elongate piloting device which extends across a length of at least 30% of the length of the cutting rollers, and which in the longitudinal profile thereof slopes downward is disposed therebetween.

Claims

1. A comminution device for product for comminution such as memory cards, mobile terminal apparatuses or the like, wherein said comminution device has a comminution unit which has two interacting cutting rollers that are rotatably driven in mutually opposite directions, each having mutually intersecting cutting discs that are disposed in an alternating manner and form a cutting gap; said cutting discs of said one cutting roller each engage in an annular groove between adjacent said cutting discs of said other cutting roller; said cutting discs have cutting edges on external peripheral edges; said cutting discs along an external circumference have a plurality of teeth, each said tooth having one tooth tip and one tooth blade on said tooth tip; said teeth or said tooth blades, respectively, of said cutting discs are aligned such that the former during operation of said comminution unit upon rotation of said cutting rollers each lie beside said teeth or said tooth blades, respectively, of said other cutting roller; said comminution device has an infeed having an infeed track for said product for comminution to said comminution unit, so as to offer up in a self-acting manner said product for comminution above said comminution unit; said infeed track terminates above said comminution unit, or above said cutting gap, respectively, wherein an elongate piloting device is disposed below an end of said infeed track and above said comminution unit; said piloting device extends across a length of at least 30% of a length of said cutting rollers, herein sloping downward in a longitudinal profile thereof.

2. The comminution device according to claim 1, wherein said tooth blade has a longitudinal direction that is parallel with longitudinal directions of said cutting rollers.

3. The comminution device according to claim 1, wherein said teeth of said directly mutually engaging and mutually opposite cutting discs are mirror-symmetrical in relation to a central plane between said cutting rollers, or in each rotary position of said cutting rollers are equally mutually spaced apart.

4. The comminution device according to claim 1, wherein said spacings of said teeth on one said cutting disc are uniform.

5. The comminution device according to claim 4, wherein said spacings of said teeth on one said cutting disc are uniform in the case of both said cutting rollers.

6. The comminution device according to claim 1, wherein said teeth are configured in a saw-tooth manner so as to be forwardly oblique, pointing in a rotation direction of said cutting rollers.

7. The comminution device according to claim 1, wherein depressions for forming said teeth are provided in said cutting rollers or in said cutting discs thereof, respectively.

8. The comminution device according to claim 7, wherein said depressions and said teeth of a cutting roller each run along lines that run so as to be non-parallel with a longitudinal axis of said cutting roller.

9. The comminution device according to claim 7, wherein said depressions and said teeth of one said cutting roller each run along lines that have an angle between 1 and 10 in relation to a plane through a longitudinal axis of said cutting roller.

10. The comminution device according to claim 1, wherein said piloting device covers between 30% and 70% of a length of said cutting gap between said cutting rollers.

11. The comminution device according to claim 10, wherein said piloting device runs above said cutting gap.

12. The comminution device according to claim 10, wherein said piloting device at least in regions covers a central line between said two cutting rollers.

13. The comminution device according to claim 1, wherein a guide duct is provided between said infeed track and said comminution unit or said cutting rollers, respectively, and said infeed track reaches up to a side of said guide duct, wherein said piloting device is disposed on an opposite side of said guide duct.

14. The comminution device according to claim 1, wherein a width of said piloting device is between 30% and 70% of a width of said guide duct in said direction.

15. A method for operating a comminution device according to claim 1, wherein load measurement is performed on said drive motor to said comminution unit during operation, so as to detect whether said comminution unit has acquired product for comminution, and in the case in which no acquisition of said product for comminution has been detected, said drive motor after a period between 2 seconds and 20 seconds rotates said comminution unit in an opposite direction, or reverses said rotation direction of said cutting rollers in relation to said operation direction, respectively, for a period between 0.5 seconds and 5 seconds, wherein said drive motor is subsequently stopped again, and drives said comminution unit in a normal operation direction again.

16. The method according to claim 15, wherein upon reversal of said rotation direction of said cutting rollers and re-starting said cutting rollers in said operation direction, it is again detected by way of load measurement on said drive motor whether said comminution unit has acquired said product for comminution, wherein in the case in which said comminution unit has again failed to acquire said product for comminution, operation of said comminution unit is again reversed.

17. The method according to claim 16, wherein said procedure is repeated between two and ten times.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Exemplary embodiments of the invention are schematically illustrated in the drawings and will be explained in more detail hereunder. In the drawings:

[0027] FIG. 1 shows a lateral sectional illustration of a comminution device according to the invention.

[0028] FIG. 2 shows an enlargement of a comminution unit of the comminution device of FIG. 1.

[0029] FIG. 3 shows a simplified illustration of the comminution unit of FIG. 2, having the cutting rollers and cutting discs, including a central plane that is illustrated with a dashed line, and

[0030] FIG. 4 shows a sectional illustration of the comminution device of FIG. 1 from above, with a view into the comminution unit.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT

[0031] A comminution device 11 according to the invention, such as may be used in an office or a smaller enterprise, for example, for comminuting the product for comminution mentioned at the outset, or above all for destroying the digital data stored therein, respectively, is illustrated in FIG. 1. The comminution device may be approx. 0.8 m to 1.5 m in size and advantageously be operated by a usual mains connection.

[0032] The comminution device 11 has a housing 12 having a slot-type infeed opening 14 having the exemplary dimensions of 4 cm16 cm and being long and wide enough for the product for comminution envisaged. An infeed 16 having an oblique infeed track 17 adjoins the infeed opening 14 on the upper side of the comminution device 11. Said infeed track 17 leads to a guide duct 19, or transitions directly into one of the walls 20a and 20b of the latter, respectively, specifically into the left wall 20a. The guide duct 19 herein runs vertically, but this is not mandatory. Said guide duct 19 has a width of 16 cm, like the infeed opening 14, wherein these dimensions may also well be double this size.

[0033] A piloting device 21 which can be better seen in the plan view of FIG. 4 is disposed at the bottom in the guide duct 19, below the infeed track 17. The piloting device 21 which here is viewed on the lower side thereof, herein is an elongate sheet-metal panel and is fastened to the right wall 20b of the guide duct 19, bearing on the latter. Said piloting device 21 herein is obliquely inclined to the right towards the wall 20b, sloped downward, or forms a type of V-shape channel with the latter, respectively. In the longitudinal extent thereof, said piloting device 21 is sloped downward into the drawing plane, as can be seen by way of the free end 22 that lies further below. A comminution unit 24 which in principle has many constructive commonalities with known comminution units or cutting units of shredders mentioned at the outset is located below the piloting device 21. The comminution unit 24 has a drive motor 26 which, as is shown on the left in FIG. 4, drives the comminution unit 24 in a known manner by way of a chain which is illustrated in a simplified manner.

[0034] The comminution unit 24 has a left cutting roller 28a and a right cutting roller 28b, each having left cutting discs 29a and right cutting discs 29b. The cutting discs 29a and 29b each have teeth 30a and 30b, and tooth blades 31a and 31b that are provided on tooth tips. Depressions 33a and 33b are located in each case between two successive teeth of the same cutting disc, as can clearly be seen from the enlarged illustration of FIG. 2. The teeth 30a and 30b herein are inclined in the rotation direction or operation direction, respectively, of the cutting discs 29a and 29b such that said teeth 30a and 30b are configured in a saw-tooth or ripper-tooth type manner. 14 teeth 30a and 30b are provided for each cutting disc 29a and 29b. As is highlighted above all by the plan view of FIG. 4, the cutting discs 29a and 29b of the cutting rollers 28a and 28b engage in one another in a directly adjacent manner. So-called scrapers 35, specifically left scrapers 35a and right scrapers 35b, are provided as stationary narrow protrusions between the annular grooves between in each case two of the cutting discs 29 of a cutting roller 28. Said scrapers 35 are however known from the prior art, and are intended for removing particles or parts of the product for comminution from the annular grooves between the cutting discs 29.

[0035] It can also be seen in FIG. 4 how the teeth 30 and the depressions 33 run along lines which slightly diverge from the left to the right, herein at an opening angle of approx. 10 between the lines of both cutting rollers. Thus, the somewhat different opening widths exist in the right region than in the left region at any given time.

[0036] The comminution unit 24 is open towards the bottom. Collection containers or the like may be introduced in a collection space 39 that is provided below said comminution unit 24, so as to collect and accumulate the comminuted product for comminution.

[0037] A cutting gap 37 which obviously lies between the two cutting rollers 28a and 29b is illustrated in the enlarged illustration of the comminution unit 24 including the infeed 16 in FIG. 2. Herein, two teeth 30a and 30b are just about to mutually engage such that the cutting gap 37 is almost closed. It can also be readily seen from the enlargement that the cutting discs 29a and 29b overlap completely, even in the case of the depressions 33a and 33b lying on a plane on which the two rotation axes of the cutting rollers 28a and 28b lie.

[0038] A likely and desired path A for large product for comminution, for example the aforementioned mobile terminal apparatuses, is illustrated in the guide duct 19. This path A emanates from above via the infeed 16 or the infeed track 17, respectively, leading via the piloting device 21. By way of the arrangement of the piloting device 21 on the wall 20b, the latter lying opposite the infeed track 17, it is ensured that such product for comminution therefrom also lands on the piloting device 21. The product for comminution then by way of the free end 22 of the piloting device 21 slides down into the comminution unit 24, or towards the cutting gap 37, respectively. As can be seen from FIG. 4, the length of the piloting device 21 is somewhat more than half the length of the cutting gap 37, or of the length of the cutting rollers 28a and 28b, respectively. In the right region, here illustrated in FIG. 4, the opening width on the teeth 30a and 30b is somewhat larger such that large items may better be acquired and drawn into the comminution unit 24 here. This has already been discussed above. The concept and purpose of the piloting device 21 is thus to ensure that large product for comminution as far as possible arrives between the cutting rollers 28a and 28b in this right region and not in the left region.

[0039] A path B for product for comminution which slides downward on the infeed track 17, falling past the piloting device 21 on the left, into the comminution unit 24 is illustrated in FIG. 2. Said product for comminution may be memory cards or so-called SD cards, respectively, which for being drawn in and comminuted or destroyed, respectively, may readily and reliably be acquired by the comminution unit 24 or by the cutting rollers 28a and 28b, respectively.

[0040] According to the path B, even comparatively large mobile terminal apparatuses in the form of tablet computers may be infed, the latter thus also entering the comminution unit 24 by bypassing the piloting device 21. However, said comparatively large terminal apparatuses are not brought in by way of the infeed opening 14. A movable or displaceable flap 15, respectively, on which the infeed opening 14 is provided on the left, is pushed to the side for said comparatively large terminal apparatuses, thus clearing the access directly from above, bypassing the piloting device 21, into the comminution unit 24. Comminuting is no problem for tablet computers of this type, as they are rather thin and thus are reliable acquired by the cutting rollers in each region.

[0041] Finally, a path B in which small product for comminution may possibly also drop onto the piloting device 21, but then not slide off the latter by way of the free end 22 but slide laterally towards the outside is also illustrated. This is also envisaged in this manner and is acceptable.

[0042] A previously described method for operating the comminution device 11 according to the figures is readily imaginable by means of the figures and need not be repeated yet again in detail. A load measurement, as has been mentioned previously, is located in a power supply to the drive motor 26, said load measurement being advantageously connected to an actuator (not illustrated herein) of the comminution device 11 for the drive motor 26. It may be identified at the top of the infeed opening 14 or in the infeed 16, alternatively also on the displaceable flap 15, advantageously by way of light barriers, micro switches or the like, if and when product for comminution has been introduced. The drive motor 26 may then be started, setting the cutting rollers 28a and 28b of the comminution unit 24 in motion in the operation direction, as is indicated in FIG. 2. If after a short period, for example after the aforementioned few seconds, it is identified by means of the load measurement on the drive motor that the load has not increased, or that infed product for comminution has not yet been acquired, the procedure of reversing the rotation direction is performed for a short period. By reversing the rotation direction, the product for comminution is intended to be modified in terms of the position thereof, or the contact thereof, respectively, in relation to the cutting rollers 28a and 28b, or in relation to the teeth 30, respectively, such that acquiring is performed upon another reversal of the rotation direction to the operation direction. If and when the product for comminution has then still not been acquired, this being detectable by an unchanged low load on the drive motor 26, the procedure of reversing the rotation direction is repeated, optionally multiple times, as has been explained above.